Below variables are defined per compress type.
- struct list_head comp_idle_workspace[BTRFS_COMPRESS_TYPES]
- spinlock_t comp_workspace_lock[BTRFS_COMPRESS_TYPES]
- int comp_num_workspace[BTRFS_COMPRESS_TYPES]
- atomic_t comp_alloc_workspace[BTRFS_COMPRESS_TYPES]
- wait_queue_head_t comp_workspace_wait[BTRFS_COMPRESS_TYPES]
BTW, while accessing one compress type of these variables, the next or
before address is other compress types of it.
So this patch puts these variables in a struct to make cache friendly.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch eliminates the last item of prop_handlers array which is used
to check end of array and instead uses ARRAY_SIZE macro.
Though this is a very tiny optimization, using ARRAY_SIZE macro is a
good practice to iterate array.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just fix a typo in the code comment.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: David Sterba <dsterba@suse.com>
rsv_count ultimately gets passed to start_transaction() which
now takes an unsigned int as its num_items parameter.
The value of rsv_count should always be positive so declare it
as being unsigned.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value of num_items that start_transaction() ultimately
always takes is a small one, so a 64 bit integer is overkill.
Also change num_items for btrfs_start_transaction() and
btrfs_start_transaction_lflush() as well.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Improve readability by generalizing the profile validity checks.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The commit b37392ea86 ("Btrfs: cleanup unnecessary parameter
and variant of prepare_pages()") makes it redundant.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Shan Hai <haishan.bai@hotmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_raid_array[] holds attributes of all raid types.
Use btrfs_raid_array[].devs_min is best way for request
in btrfs_reduce_alloc_profile(), instead of use complex
condition of each raid types.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_raid_array[] is used to define all raid attributes, use it
to get tolerated_failures in btrfs_get_num_tolerated_disk_barrier_failures(),
instead of complex condition in function.
It can make code simple and auto-support other possible raid-type in
future.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This array is used to record attributes of each raid type,
make it public, and many functions will benifit with this array.
For example, num_tolerated_disk_barrier_failures(), we can
avoid complex conditions in this function, and get raid attribute
simply by accessing above array.
It can also make code logic simple, reduce duplication code, and
increase maintainability.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rather than have three separate if() statements for the same outcome
we should just OR them together in the same if() statement.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use memset() to null out the btrfs_delayed_ref_root of
btrfs_transaction instead of setting all the members to 0 by hand.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We can safely iterate whole list items, without using list_del macro.
So remove the list_del call.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no removing list element while iterating over list.
So, replace list_for_each_entry_safe to list_for_each_entry.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just call kmem_cache_zalloc() instead of calling kmem_cache_alloc().
We're just initializing most fields to 0, false and NULL later on
_anyway_, so to make the code mode readable and potentially gain
a bit of performance (completely untested claim), we should fill our
btrfs_trans_handle with zeros on allocation then just initialize
those five remaining fields (not counting the list_heads) as normal.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
old_len is used to store the return value of btrfs_item_size_nr().
The return value of btrfs_item_size_nr() is of type u32.
To improve code correctness and avoid mixing signed and unsigned
integers I've changed old_len to be of type u32 as well.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The return values of btrfs_item_offset_nr and btrfs_item_size_nr are of
type u32. To avoid mixing signed and unsigned integers we should also
declare dsize and last_off to be of type u32.
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Current code will always truncate tailing page if its alloc_start is
smaller than inode size.
For example, the file extent layout is like:
0 4K 8K 16K 32K
|<-----Extent A---------------->|
|<--Inode size: 18K---------->|
But if calling fallocate even for range [0,4K), it will cause btrfs to
re-truncate the range [16,32K), causing COW and a new extent.
0 4K 8K 16K 32K
|///////| <- Fallocate call range
|<-----Extent A-------->|<--B-->|
The cause is quite easy, just a careless btrfs_truncate_inode() in a
else branch without extra judgment.
Fix it by add judgment on whether the fallocate range is beyond isize.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When truncating a file to a smaller size which consists of an inline
extent that is compressed, we did not discard (or made unusable) the
data between the new file size and the old file size, wasting metadata
space and allowing for the truncated data to be leaked and the data
corruption/loss mentioned below.
We were also not correctly decrementing the number of bytes used by the
inode, we were setting it to zero, giving a wrong report for callers of
the stat(2) syscall. The fsck tool also reported an error about a mismatch
between the nbytes of the file versus the real space used by the file.
Now because we weren't discarding the truncated region of the file, it
was possible for a caller of the clone ioctl to actually read the data
that was truncated, allowing for a security breach without requiring root
access to the system, using only standard filesystem operations. The
scenario is the following:
1) User A creates a file which consists of an inline and compressed
extent with a size of 2000 bytes - the file is not accessible to
any other users (no read, write or execution permission for anyone
else);
2) The user truncates the file to a size of 1000 bytes;
3) User A makes the file world readable;
4) User B creates a file consisting of an inline extent of 2000 bytes;
5) User B issues a clone operation from user A's file into its own
file (using a length argument of 0, clone the whole range);
6) User B now gets to see the 1000 bytes that user A truncated from
its file before it made its file world readbale. User B also lost
the bytes in the range [1000, 2000[ bytes from its own file, but
that might be ok if his/her intention was reading stale data from
user A that was never supposed to be public.
Note that this contrasts with the case where we truncate a file from 2000
bytes to 1000 bytes and then truncate it back from 1000 to 2000 bytes. In
this case reading any byte from the range [1000, 2000[ will return a value
of 0x00, instead of the original data.
This problem exists since the clone ioctl was added and happens both with
and without my recent data loss and file corruption fixes for the clone
ioctl (patch "Btrfs: fix file corruption and data loss after cloning
inline extents").
So fix this by truncating the compressed inline extents as we do for the
non-compressed case, which involves decompressing, if the data isn't already
in the page cache, compressing the truncated version of the extent, writing
the compressed content into the inline extent and then truncate it.
The following test case for fstests reproduces the problem. In order for
the test to pass both this fix and my previous fix for the clone ioctl
that forbids cloning a smaller inline extent into a larger one,
which is titled "Btrfs: fix file corruption and data loss after cloning
inline extents", are needed. Without that other fix the test fails in a
different way that does not leak the truncated data, instead part of
destination file gets replaced with zeroes (because the destination file
has a larger inline extent than the source).
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_need_to_be_root
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_cloner
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount "-o compress"
# Create our test files. File foo is going to be the source of a clone operation
# and consists of a single inline extent with an uncompressed size of 512 bytes,
# while file bar consists of a single inline extent with an uncompressed size of
# 256 bytes. For our test's purpose, it's important that file bar has an inline
# extent with a size smaller than foo's inline extent.
$XFS_IO_PROG -f -c "pwrite -S 0xa1 0 128" \
-c "pwrite -S 0x2a 128 384" \
$SCRATCH_MNT/foo | _filter_xfs_io
$XFS_IO_PROG -f -c "pwrite -S 0xbb 0 256" $SCRATCH_MNT/bar | _filter_xfs_io
# Now durably persist all metadata and data. We do this to make sure that we get
# on disk an inline extent with a size of 512 bytes for file foo.
sync
# Now truncate our file foo to a smaller size. Because it consists of a
# compressed and inline extent, btrfs did not shrink the inline extent to the
# new size (if the extent was not compressed, btrfs would shrink it to 128
# bytes), it only updates the inode's i_size to 128 bytes.
$XFS_IO_PROG -c "truncate 128" $SCRATCH_MNT/foo
# Now clone foo's inline extent into bar.
# This clone operation should fail with errno EOPNOTSUPP because the source
# file consists only of an inline extent and the file's size is smaller than
# the inline extent of the destination (128 bytes < 256 bytes). However the
# clone ioctl was not prepared to deal with a file that has a size smaller
# than the size of its inline extent (something that happens only for compressed
# inline extents), resulting in copying the full inline extent from the source
# file into the destination file.
#
# Note that btrfs' clone operation for inline extents consists of removing the
# inline extent from the destination inode and copy the inline extent from the
# source inode into the destination inode, meaning that if the destination
# inode's inline extent is larger (N bytes) than the source inode's inline
# extent (M bytes), some bytes (N - M bytes) will be lost from the destination
# file. Btrfs could copy the source inline extent's data into the destination's
# inline extent so that we would not lose any data, but that's currently not
# done due to the complexity that would be needed to deal with such cases
# (specially when one or both extents are compressed), returning EOPNOTSUPP, as
# it's normally not a very common case to clone very small files (only case
# where we get inline extents) and copying inline extents does not save any
# space (unlike for normal, non-inlined extents).
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/foo $SCRATCH_MNT/bar
# Now because the above clone operation used to succeed, and due to foo's inline
# extent not being shinked by the truncate operation, our file bar got the whole
# inline extent copied from foo, making us lose the last 128 bytes from bar
# which got replaced by the bytes in range [128, 256[ from foo before foo was
# truncated - in other words, data loss from bar and being able to read old and
# stale data from foo that should not be possible to read anymore through normal
# filesystem operations. Contrast with the case where we truncate a file from a
# size N to a smaller size M, truncate it back to size N and then read the range
# [M, N[, we should always get the value 0x00 for all the bytes in that range.
# We expected the clone operation to fail with errno EOPNOTSUPP and therefore
# not modify our file's bar data/metadata. So its content should be 256 bytes
# long with all bytes having the value 0xbb.
#
# Without the btrfs bug fix, the clone operation succeeded and resulted in
# leaking truncated data from foo, the bytes that belonged to its range
# [128, 256[, and losing data from bar in that same range. So reading the
# file gave us the following content:
#
# 0000000 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1
# *
# 0000200 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a
# *
# 0000400
echo "File bar's content after the clone operation:"
od -t x1 $SCRATCH_MNT/bar
# Also because the foo's inline extent was not shrunk by the truncate
# operation, btrfs' fsck, which is run by the fstests framework everytime a
# test completes, failed reporting the following error:
#
# root 5 inode 257 errors 400, nbytes wrong
status=0
exit
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Pull btrfs fixes from Chris Mason:
"I have two more bug fixes for btrfs.
My commit fixes a bug we hit last week at FB, a combination of lots of
hard links and an admin command to resolve inode numbers.
Dave is adding checks to make sure balance on current kernels ignores
filters it doesn't understand. The penalty for being wrong is just
doing more work (not crashing etc), but it's a good fix"
* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix use after free iterating extrefs
btrfs: check unsupported filters in balance arguments
If when reading a page we find a hole and our caller had already locked
the range (bio flags has the bit EXTENT_BIO_PARENT_LOCKED set), we end
up unlocking the hole's range and then later our caller unlocks it
again, which might have already been locked by some other task once
the first unlock happened.
Currently this can only happen during a call to the extent_same ioctl,
as it's the only caller of __do_readpage() that sets the bit
EXTENT_BIO_PARENT_LOCKED for bio flags.
Fix this by leaving the unlock exclusively to the caller.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Currently the clone ioctl allows to clone an inline extent from one file
to another that already has other (non-inlined) extents. This is a problem
because btrfs is not designed to deal with files having inline and regular
extents, if a file has an inline extent then it must be the only extent
in the file and must start at file offset 0. Having a file with an inline
extent followed by regular extents results in EIO errors when doing reads
or writes against the first 4K of the file.
Also, the clone ioctl allows one to lose data if the source file consists
of a single inline extent, with a size of N bytes, and the destination
file consists of a single inline extent with a size of M bytes, where we
have M > N. In this case the clone operation removes the inline extent
from the destination file and then copies the inline extent from the
source file into the destination file - we lose the M - N bytes from the
destination file, a read operation will get the value 0x00 for any bytes
in the the range [N, M] (the destination inode's i_size remained as M,
that's why we can read past N bytes).
So fix this by not allowing such destructive operations to happen and
return errno EOPNOTSUPP to user space.
Currently the fstest btrfs/035 tests the data loss case but it totally
ignores this - i.e. expects the operation to succeed and does not check
the we got data loss.
The following test case for fstests exercises all these cases that result
in file corruption and data loss:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_need_to_be_root
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_cloner
_require_btrfs_fs_feature "no_holes"
_require_btrfs_mkfs_feature "no-holes"
rm -f $seqres.full
test_cloning_inline_extents()
{
local mkfs_opts=$1
local mount_opts=$2
_scratch_mkfs $mkfs_opts >>$seqres.full 2>&1
_scratch_mount $mount_opts
# File bar, the source for all the following clone operations, consists
# of a single inline extent (50 bytes).
$XFS_IO_PROG -f -c "pwrite -S 0xbb 0 50" $SCRATCH_MNT/bar \
| _filter_xfs_io
# Test cloning into a file with an extent (non-inlined) where the
# destination offset overlaps that extent. It should not be possible to
# clone the inline extent from file bar into this file.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 16K" $SCRATCH_MNT/foo \
| _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo
# Doing IO against any range in the first 4K of the file should work.
# Due to a past clone ioctl bug which allowed cloning the inline extent,
# these operations resulted in EIO errors.
echo "File foo data after clone operation:"
# All bytes should have the value 0xaa (clone operation failed and did
# not modify our file).
od -t x1 $SCRATCH_MNT/foo
$XFS_IO_PROG -c "pwrite -S 0xcc 0 100" $SCRATCH_MNT/foo | _filter_xfs_io
# Test cloning the inline extent against a file which has a hole in its
# first 4K followed by a non-inlined extent. It should not be possible
# as well to clone the inline extent from file bar into this file.
$XFS_IO_PROG -f -c "pwrite -S 0xdd 4K 12K" $SCRATCH_MNT/foo2 \
| _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo2
# Doing IO against any range in the first 4K of the file should work.
# Due to a past clone ioctl bug which allowed cloning the inline extent,
# these operations resulted in EIO errors.
echo "File foo2 data after clone operation:"
# All bytes should have the value 0x00 (clone operation failed and did
# not modify our file).
od -t x1 $SCRATCH_MNT/foo2
$XFS_IO_PROG -c "pwrite -S 0xee 0 90" $SCRATCH_MNT/foo2 | _filter_xfs_io
# Test cloning the inline extent against a file which has a size of zero
# but has a prealloc extent. It should not be possible as well to clone
# the inline extent from file bar into this file.
$XFS_IO_PROG -f -c "falloc -k 0 1M" $SCRATCH_MNT/foo3 | _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo3
# Doing IO against any range in the first 4K of the file should work.
# Due to a past clone ioctl bug which allowed cloning the inline extent,
# these operations resulted in EIO errors.
echo "First 50 bytes of foo3 after clone operation:"
# Should not be able to read any bytes, file has 0 bytes i_size (the
# clone operation failed and did not modify our file).
od -t x1 $SCRATCH_MNT/foo3
$XFS_IO_PROG -c "pwrite -S 0xff 0 90" $SCRATCH_MNT/foo3 | _filter_xfs_io
# Test cloning the inline extent against a file which consists of a
# single inline extent that has a size not greater than the size of
# bar's inline extent (40 < 50).
# It should be possible to do the extent cloning from bar to this file.
$XFS_IO_PROG -f -c "pwrite -S 0x01 0 40" $SCRATCH_MNT/foo4 \
| _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo4
# Doing IO against any range in the first 4K of the file should work.
echo "File foo4 data after clone operation:"
# Must match file bar's content.
od -t x1 $SCRATCH_MNT/foo4
$XFS_IO_PROG -c "pwrite -S 0x02 0 90" $SCRATCH_MNT/foo4 | _filter_xfs_io
# Test cloning the inline extent against a file which consists of a
# single inline extent that has a size greater than the size of bar's
# inline extent (60 > 50).
# It should not be possible to clone the inline extent from file bar
# into this file.
$XFS_IO_PROG -f -c "pwrite -S 0x03 0 60" $SCRATCH_MNT/foo5 \
| _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo5
# Reading the file should not fail.
echo "File foo5 data after clone operation:"
# Must have a size of 60 bytes, with all bytes having a value of 0x03
# (the clone operation failed and did not modify our file).
od -t x1 $SCRATCH_MNT/foo5
# Test cloning the inline extent against a file which has no extents but
# has a size greater than bar's inline extent (16K > 50).
# It should not be possible to clone the inline extent from file bar
# into this file.
$XFS_IO_PROG -f -c "truncate 16K" $SCRATCH_MNT/foo6 | _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo6
# Reading the file should not fail.
echo "File foo6 data after clone operation:"
# Must have a size of 16K, with all bytes having a value of 0x00 (the
# clone operation failed and did not modify our file).
od -t x1 $SCRATCH_MNT/foo6
# Test cloning the inline extent against a file which has no extents but
# has a size not greater than bar's inline extent (30 < 50).
# It should be possible to clone the inline extent from file bar into
# this file.
$XFS_IO_PROG -f -c "truncate 30" $SCRATCH_MNT/foo7 | _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo7
# Reading the file should not fail.
echo "File foo7 data after clone operation:"
# Must have a size of 50 bytes, with all bytes having a value of 0xbb.
od -t x1 $SCRATCH_MNT/foo7
# Test cloning the inline extent against a file which has a size not
# greater than the size of bar's inline extent (20 < 50) but has
# a prealloc extent that goes beyond the file's size. It should not be
# possible to clone the inline extent from bar into this file.
$XFS_IO_PROG -f -c "falloc -k 0 1M" \
-c "pwrite -S 0x88 0 20" \
$SCRATCH_MNT/foo8 | _filter_xfs_io
$CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo8
echo "File foo8 data after clone operation:"
# Must have a size of 20 bytes, with all bytes having a value of 0x88
# (the clone operation did not modify our file).
od -t x1 $SCRATCH_MNT/foo8
_scratch_unmount
}
echo -e "\nTesting without compression and without the no-holes feature...\n"
test_cloning_inline_extents
echo -e "\nTesting with compression and without the no-holes feature...\n"
test_cloning_inline_extents "" "-o compress"
echo -e "\nTesting without compression and with the no-holes feature...\n"
test_cloning_inline_extents "-O no-holes" ""
echo -e "\nTesting with compression and with the no-holes feature...\n"
test_cloning_inline_extents "-O no-holes" "-o compress"
status=0
exit
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
The code for btrfs inode-resolve has never worked properly for
files with enough hard links to trigger extrefs. It was trying to
get the leaf out of a path after freeing the path:
btrfs_release_path(path);
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, slot);
The fix here is to use the extent buffer we cloned just a little higher
up to avoid deadlocks caused by using the leaf in the path.
Signed-off-by: Chris Mason <clm@fb.com>
cc: stable@vger.kernel.org # v3.7+
cc: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
We don't verify that all the balance filter arguments supplemented by
the flags are actually known to the kernel. Thus we let it silently pass
and do nothing.
At the moment this means only the 'limit' filter, but we're going to add
a few more soon so it's better to have that fixed. Also in older stable
kernels so that it works with newer userspace tools.
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
This fixes a regression introduced by 37b8d27d between v4.1 and v4.2.
When a snapshot is received, its received_uuid is set to the original
uuid of the subvolume. When that snapshot is then resent to a third
filesystem, it's received_uuid is set to the second uuid
instead of the original one. The same was true for the parent_uuid.
This behaviour was partially changed in 37b8d27d, but in that patch
only the parent_uuid was taken from the real original,
not the uuid itself, causing the search for the parent to fail in
the case below.
This happens for example when trying to send a series of linked
snapshots (e.g. created by snapper) from the backup file system back
to the original one.
The following commands reproduce the issue in v4.2.1
(no error in 4.1.6)
# setup three test file systems
for i in 1 2 3; do
truncate -s 50M fs$i
mkfs.btrfs fs$i
mkdir $i
mount fs$i $i
done
echo "content" > 1/testfile
btrfs su snapshot -r 1/ 1/snap1
echo "changed content" > 1/testfile
btrfs su snapshot -r 1/ 1/snap2
# works fine:
btrfs send 1/snap1 | btrfs receive 2/
btrfs send -p 1/snap1 1/snap2 | btrfs receive 2/
# ERROR: could not find parent subvolume
btrfs send 2/snap1 | btrfs receive 3/
btrfs send -p 2/snap1 2/snap2 | btrfs receive 3/
Signed-off-by: Robin Ruede <rruede+git@gmail.com>
Fixes: 37b8d27de5 ("Btrfs: use received_uuid of parent during send")
Cc: stable@vger.kernel.org # v4.2+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Ed Tomlinson <edt@aei.ca>
If we have a file that shares an extent with other files, when processing
the extent item relative to a shared extent, we blindly issue a clone
operation that will target a length matching the length in the extent item
and uses as a source some other file the receiver already has and points
to the same extent. However that range in the other file might not
exclusively point only to the shared extent, and so using that length
will result in the receiver getting a file with different data from the
one in the send snapshot. This issue happened both for incremental and
full send operations.
So fix this by issuing clone operations with lengths that don't cover
regions of the source file that point to different extents (or have holes).
The following test case for fstests reproduces the problem.
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -fr $send_files_dir
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_need_to_be_root
_require_cp_reflink
_require_xfs_io_command "fpunch"
send_files_dir=$TEST_DIR/btrfs-test-$seq
rm -f $seqres.full
rm -fr $send_files_dir
mkdir $send_files_dir
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
# Create our test file with a single 100K extent.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 100K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Clone our file into a new file named bar.
cp --reflink=always $SCRATCH_MNT/foo $SCRATCH_MNT/bar
# Now overwrite parts of our foo file.
$XFS_IO_PROG -c "pwrite -S 0xbb 50K 10K" \
-c "pwrite -S 0xcc 90K 10K" \
-c "fpunch 70K 10k" \
$SCRATCH_MNT/foo | _filter_xfs_io
_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \
$SCRATCH_MNT/snap
echo "File digests in the original filesystem:"
md5sum $SCRATCH_MNT/snap/foo | _filter_scratch
md5sum $SCRATCH_MNT/snap/bar | _filter_scratch
_run_btrfs_util_prog send $SCRATCH_MNT/snap -f $send_files_dir/1.snap
# Now recreate the filesystem by receiving the send stream and verify
# we get the same file contents that the original filesystem had.
_scratch_unmount
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/1.snap
# We expect the destination filesystem to have exactly the same file
# data as the original filesystem.
# The btrfs send implementation had a bug where it sent a clone
# operation from file foo into file bar covering the whole [0, 100K[
# range after creating and writing the file foo. This was incorrect
# because the file bar now included the updates done to file foo after
# we cloned foo to bar, breaking the COW nature of reflink copies
# (cloned extents).
echo "File digests in the new filesystem:"
md5sum $SCRATCH_MNT/snap/foo | _filter_scratch
md5sum $SCRATCH_MNT/snap/bar | _filter_scratch
status=0
exit
Another test case that reproduces the problem when we have compressed
extents:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -fr $send_files_dir
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_need_to_be_root
_require_cp_reflink
send_files_dir=$TEST_DIR/btrfs-test-$seq
rm -f $seqres.full
rm -fr $send_files_dir
mkdir $send_files_dir
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount "-o compress"
# Create our file with an extent of 100K starting at file offset 0K.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 100K" \
-c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Rewrite part of the previous extent (its first 40K) and write a new
# 100K extent starting at file offset 100K.
$XFS_IO_PROG -c "pwrite -S 0xbb 0K 40K" \
-c "pwrite -S 0xcc 100K 100K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Our file foo now has 3 file extent items in its metadata:
#
# 1) One covering the file range 0 to 40K;
# 2) One covering the file range 40K to 100K, which points to the first
# extent we wrote to the file and has a data offset field with value
# 40K (our file no longer uses the first 40K of data from that
# extent);
# 3) One covering the file range 100K to 200K.
# Now clone our file foo into file bar.
cp --reflink=always $SCRATCH_MNT/foo $SCRATCH_MNT/bar
# Create our snapshot for the send operation.
_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \
$SCRATCH_MNT/snap
echo "File digests in the original filesystem:"
md5sum $SCRATCH_MNT/snap/foo | _filter_scratch
md5sum $SCRATCH_MNT/snap/bar | _filter_scratch
_run_btrfs_util_prog send $SCRATCH_MNT/snap -f $send_files_dir/1.snap
# Now recreate the filesystem by receiving the send stream and verify we
# get the same file contents that the original filesystem had.
# Btrfs send used to issue a clone operation from foo's range
# [80K, 140K[ to bar's range [40K, 100K[ when cloning the extent pointed
# to by foo's second file extent item, this was incorrect because of bad
# accounting of the file extent item's data offset field. The correct
# range to clone from should have been [40K, 100K[.
_scratch_unmount
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount "-o compress"
_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/1.snap
echo "File digests in the new filesystem:"
# Must match the digests we got in the original filesystem.
md5sum $SCRATCH_MNT/snap/foo | _filter_scratch
md5sum $SCRATCH_MNT/snap/bar | _filter_scratch
status=0
exit
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Removing barriers is scary, but a call to atomic_dec_and_test implies
a barrier, so we don't need to issue another one.
Signed-off-by: David Sterba <dsterba@suse.com>
waitqueue_active should be preceded by a barrier, in this function we
don't need to call it all the time.
Signed-off-by: David Sterba <dsterba@suse.com>
Normally the waitqueue_active would need a barrier, but this is not
necessary here because it's not a performance sensitive context and we
can call wake_up directly.
Suggested-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from Chris Mason:
"These are small and assorted. Neil's is the oldest, I dropped the
ball thinking he was going to send it in"
* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: support NFSv2 export
Btrfs: open_ctree: Fix possible memory leak
Btrfs: fix deadlock when finalizing block group creation
Btrfs: update fix for read corruption of compressed and shared extents
Btrfs: send, fix corner case for reference overwrite detection
Convert the simple cases, not all functions provide a way to reach the
fs_info. Also skipped debugging messages (print-tree, integrity
checker and pr_debug) and messages that are printed from possibly
unfinished mount.
Signed-off-by: David Sterba <dsterba@suse.com>
Due to the missing variants there are messages that lack the information
printed by btrfs_info etc helpers.
Signed-off-by: David Sterba <dsterba@suse.com>
The "fh_len" passed to ->fh_to_* is not guaranteed to be that same as
that returned by encode_fh - it may be larger.
With NFSv2, the filehandle is fixed length, so it may appear longer
than expected and be zero-padded.
So we must test that fh_len is at least some value, not exactly equal
to it.
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: David Sterba <dsterba@suse.cz>
After reading one of chunk or tree root tree's root node from disk, if the
root node does not have EXTENT_BUFFER_UPTODATE flag set, we fail to release
the memory used by the root node. Fix this.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Josef ran into a deadlock while a transaction handle was finalizing the
creation of its block groups, which produced the following trace:
[260445.593112] fio D ffff88022a9df468 0 8924 4518 0x00000084
[260445.593119] ffff88022a9df468 ffffffff81c134c0 ffff880429693c00 ffff88022a9df488
[260445.593126] ffff88022a9e0000 ffff8803490d7b00 ffff8803490d7b18 ffff88022a9df4b0
[260445.593132] ffff8803490d7af8 ffff88022a9df488 ffffffff8175a437 ffff8803490d7b00
[260445.593137] Call Trace:
[260445.593145] [<ffffffff8175a437>] schedule+0x37/0x80
[260445.593189] [<ffffffffa0850f37>] btrfs_tree_lock+0xa7/0x1f0 [btrfs]
[260445.593197] [<ffffffff810db7c0>] ? prepare_to_wait_event+0xf0/0xf0
[260445.593225] [<ffffffffa07eac44>] btrfs_lock_root_node+0x34/0x50 [btrfs]
[260445.593253] [<ffffffffa07eff6b>] btrfs_search_slot+0x88b/0xa00 [btrfs]
[260445.593295] [<ffffffffa08389df>] ? free_extent_buffer+0x4f/0x90 [btrfs]
[260445.593324] [<ffffffffa07f1a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs]
[260445.593351] [<ffffffffa07ea94a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs]
[260445.593394] [<ffffffffa08403b9>] btrfs_finish_chunk_alloc+0x1c9/0x570 [btrfs]
[260445.593427] [<ffffffffa08002ab>] btrfs_create_pending_block_groups+0x11b/0x200 [btrfs]
[260445.593459] [<ffffffffa0800964>] do_chunk_alloc+0x2a4/0x2e0 [btrfs]
[260445.593491] [<ffffffffa0803815>] find_free_extent+0xa55/0xd90 [btrfs]
[260445.593524] [<ffffffffa0803c22>] btrfs_reserve_extent+0xd2/0x220 [btrfs]
[260445.593532] [<ffffffff8119fe5d>] ? account_page_dirtied+0xdd/0x170
[260445.593564] [<ffffffffa0803e78>] btrfs_alloc_tree_block+0x108/0x4a0 [btrfs]
[260445.593597] [<ffffffffa080c9de>] ? btree_set_page_dirty+0xe/0x10 [btrfs]
[260445.593626] [<ffffffffa07eb5cd>] __btrfs_cow_block+0x12d/0x5b0 [btrfs]
[260445.593654] [<ffffffffa07ebbff>] btrfs_cow_block+0x11f/0x1c0 [btrfs]
[260445.593682] [<ffffffffa07ef8c7>] btrfs_search_slot+0x1e7/0xa00 [btrfs]
[260445.593724] [<ffffffffa08389df>] ? free_extent_buffer+0x4f/0x90 [btrfs]
[260445.593752] [<ffffffffa07f1a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs]
[260445.593830] [<ffffffffa07ea94a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs]
[260445.593905] [<ffffffffa08403b9>] btrfs_finish_chunk_alloc+0x1c9/0x570 [btrfs]
[260445.593946] [<ffffffffa08002ab>] btrfs_create_pending_block_groups+0x11b/0x200 [btrfs]
[260445.593990] [<ffffffffa0815798>] btrfs_commit_transaction+0xa8/0xb40 [btrfs]
[260445.594042] [<ffffffffa085abcd>] ? btrfs_log_dentry_safe+0x6d/0x80 [btrfs]
[260445.594089] [<ffffffffa082bc84>] btrfs_sync_file+0x294/0x350 [btrfs]
[260445.594115] [<ffffffff8123e29b>] vfs_fsync_range+0x3b/0xa0
[260445.594133] [<ffffffff81023891>] ? syscall_trace_enter_phase1+0x131/0x180
[260445.594149] [<ffffffff8123e35d>] do_fsync+0x3d/0x70
[260445.594169] [<ffffffff81023bb8>] ? syscall_trace_leave+0xb8/0x110
[260445.594187] [<ffffffff8123e600>] SyS_fsync+0x10/0x20
[260445.594204] [<ffffffff8175de6e>] entry_SYSCALL_64_fastpath+0x12/0x71
This happened because the same transaction handle created a large number
of block groups and while finalizing their creation (inserting new items
and updating existing items in the chunk and device trees) a new metadata
extent had to be allocated and no free space was found in the current
metadata block groups, which made find_free_extent() attempt to allocate
a new block group via do_chunk_alloc(). However at do_chunk_alloc() we
ended up allocating a new system chunk too and exceeded the threshold
of 2Mb of reserved chunk bytes, which makes do_chunk_alloc() enter the
final part of block group creation again (at
btrfs_create_pending_block_groups()) and attempt to lock again the root
of the chunk tree when it's already write locked by the same task.
Similarly we can deadlock on extent tree nodes/leafs if while we are
running delayed references we end up creating a new metadata block group
in order to allocate a new node/leaf for the extent tree (as part of
a CoW operation or growing the tree), as btrfs_create_pending_block_groups
inserts items into the extent tree as well. In this case we get the
following trace:
[14242.773581] fio D ffff880428ca3418 0 3615 3100 0x00000084
[14242.773588] ffff880428ca3418 ffff88042d66b000 ffff88042a03c800 ffff880428ca3438
[14242.773594] ffff880428ca4000 ffff8803e4b20190 ffff8803e4b201a8 ffff880428ca3460
[14242.773600] ffff8803e4b20188 ffff880428ca3438 ffffffff8175a437 ffff8803e4b20190
[14242.773606] Call Trace:
[14242.773613] [<ffffffff8175a437>] schedule+0x37/0x80
[14242.773656] [<ffffffffa057ff07>] btrfs_tree_lock+0xa7/0x1f0 [btrfs]
[14242.773664] [<ffffffff810db7c0>] ? prepare_to_wait_event+0xf0/0xf0
[14242.773692] [<ffffffffa0519c44>] btrfs_lock_root_node+0x34/0x50 [btrfs]
[14242.773720] [<ffffffffa051ef6b>] btrfs_search_slot+0x88b/0xa00 [btrfs]
[14242.773750] [<ffffffffa0520a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs]
[14242.773758] [<ffffffff811ef4a2>] ? kmem_cache_alloc+0x1d2/0x200
[14242.773786] [<ffffffffa0520ad1>] btrfs_insert_item+0x71/0xf0 [btrfs]
[14242.773818] [<ffffffffa052f292>] btrfs_create_pending_block_groups+0x102/0x200 [btrfs]
[14242.773850] [<ffffffffa052f96e>] do_chunk_alloc+0x2ae/0x2f0 [btrfs]
[14242.773934] [<ffffffffa0532825>] find_free_extent+0xa55/0xd90 [btrfs]
[14242.773998] [<ffffffffa0532c22>] btrfs_reserve_extent+0xc2/0x1d0 [btrfs]
[14242.774041] [<ffffffffa0532e38>] btrfs_alloc_tree_block+0x108/0x4a0 [btrfs]
[14242.774078] [<ffffffffa051a5cd>] __btrfs_cow_block+0x12d/0x5b0 [btrfs]
[14242.774118] [<ffffffffa051abff>] btrfs_cow_block+0x11f/0x1c0 [btrfs]
[14242.774155] [<ffffffffa051e8c7>] btrfs_search_slot+0x1e7/0xa00 [btrfs]
[14242.774194] [<ffffffffa0528021>] ? __btrfs_free_extent.isra.70+0x2e1/0xcb0 [btrfs]
[14242.774235] [<ffffffffa0520a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs]
[14242.774274] [<ffffffffa051994a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs]
[14242.774318] [<ffffffffa052c433>] __btrfs_run_delayed_refs+0xbb3/0x1020 [btrfs]
[14242.774358] [<ffffffffa052f404>] btrfs_run_delayed_refs.part.78+0x74/0x280 [btrfs]
[14242.774391] [<ffffffffa052f627>] btrfs_run_delayed_refs+0x17/0x20 [btrfs]
[14242.774432] [<ffffffffa05be236>] commit_cowonly_roots+0x8d/0x2bd [btrfs]
[14242.774474] [<ffffffffa059d07f>] ? __btrfs_run_delayed_items+0x1cf/0x210 [btrfs]
[14242.774516] [<ffffffffa05adac3>] ? btrfs_qgroup_account_extents+0x83/0x130 [btrfs]
[14242.774558] [<ffffffffa0544c40>] btrfs_commit_transaction+0x590/0xb40 [btrfs]
[14242.774599] [<ffffffffa0589b9d>] ? btrfs_log_dentry_safe+0x6d/0x80 [btrfs]
[14242.774642] [<ffffffffa055ac54>] btrfs_sync_file+0x294/0x350 [btrfs]
[14242.774650] [<ffffffff8123e29b>] vfs_fsync_range+0x3b/0xa0
[14242.774657] [<ffffffff81023891>] ? syscall_trace_enter_phase1+0x131/0x180
[14242.774663] [<ffffffff8123e35d>] do_fsync+0x3d/0x70
[14242.774669] [<ffffffff81023bb8>] ? syscall_trace_leave+0xb8/0x110
[14242.774675] [<ffffffff8123e600>] SyS_fsync+0x10/0x20
[14242.774681] [<ffffffff8175de6e>] entry_SYSCALL_64_fastpath+0x12/0x71
Fix this by never recursing into the finalization phase of block group
creation and making sure we never trigger the finalization of block group
creation while running delayed references.
Reported-by: Josef Bacik <jbacik@fb.com>
Fixes: 00d80e342c ("Btrfs: fix quick exhaustion of the system array in the superblock")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
My previous fix in commit 005efedf2c ("Btrfs: fix read corruption of
compressed and shared extents") was effective only if the compressed
extents cover a file range with a length that is not a multiple of 16
pages. That's because the detection of when we reached a different range
of the file that shares the same compressed extent as the previously
processed range was done at extent_io.c:__do_contiguous_readpages(),
which covers subranges with a length up to 16 pages, because
extent_readpages() groups the pages in clusters no larger than 16 pages.
So fix this by tracking the start of the previously processed file
range's extent map at extent_readpages().
The following test case for fstests reproduces the issue:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_need_to_be_root
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_cloner
rm -f $seqres.full
test_clone_and_read_compressed_extent()
{
local mount_opts=$1
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount $mount_opts
# Create our test file with a single extent of 64Kb that is going to
# be compressed no matter which compression algo is used (zlib/lzo).
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 64K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Now clone the compressed extent into an adjacent file offset.
$CLONER_PROG -s 0 -d $((64 * 1024)) -l $((64 * 1024)) \
$SCRATCH_MNT/foo $SCRATCH_MNT/foo
echo "File digest before unmount:"
md5sum $SCRATCH_MNT/foo | _filter_scratch
# Remount the fs or clear the page cache to trigger the bug in
# btrfs. Because the extent has an uncompressed length that is a
# multiple of 16 pages, all the pages belonging to the second range
# of the file (64K to 128K), which points to the same extent as the
# first range (0K to 64K), had their contents full of zeroes instead
# of the byte 0xaa. This was a bug exclusively in the read path of
# compressed extents, the correct data was stored on disk, btrfs
# just failed to fill in the pages correctly.
_scratch_remount
echo "File digest after remount:"
# Must match the digest we got before.
md5sum $SCRATCH_MNT/foo | _filter_scratch
}
echo -e "\nTesting with zlib compression..."
test_clone_and_read_compressed_extent "-o compress=zlib"
_scratch_unmount
echo -e "\nTesting with lzo compression..."
test_clone_and_read_compressed_extent "-o compress=lzo"
status=0
exit
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Timofey Titovets <nefelim4ag@gmail.com>
When the inode given to did_overwrite_ref() matches the current progress
and has a reference that collides with the reference of other inode that
has the same number as the current progress, we were always telling our
caller that the inode's reference was overwritten, which is incorrect
because the other inode might be a new inode (different generation number)
in which case we must return false from did_overwrite_ref() so that its
callers don't use an orphanized path for the inode (as it will never be
orphanized, instead it will be unlinked and the new inode created later).
The following test case for fstests reproduces the issue:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -fr $send_files_dir
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_need_to_be_root
send_files_dir=$TEST_DIR/btrfs-test-$seq
rm -f $seqres.full
rm -fr $send_files_dir
mkdir $send_files_dir
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
# Create our test file with a single extent of 64K.
mkdir -p $SCRATCH_MNT/foo
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 64K" $SCRATCH_MNT/foo/bar \
| _filter_xfs_io
_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \
$SCRATCH_MNT/mysnap1
_run_btrfs_util_prog subvolume snapshot $SCRATCH_MNT \
$SCRATCH_MNT/mysnap2
echo "File digest before being replaced:"
md5sum $SCRATCH_MNT/mysnap1/foo/bar | _filter_scratch
# Remove the file and then create a new one in the same location with
# the same name but with different content. This new file ends up
# getting the same inode number as the previous one, because that inode
# number was the highest inode number used by the snapshot's root and
# therefore when attempting to find the a new inode number for the new
# file, we end up reusing the same inode number. This happens because
# currently btrfs uses the highest inode number summed by 1 for the
# first inode created once a snapshot's root is loaded (done at
# fs/btrfs/inode-map.c:btrfs_find_free_objectid in the linux kernel
# tree).
# Having these two different files in the snapshots with the same inode
# number (but different generation numbers) caused the btrfs send code
# to emit an incorrect path for the file when issuing an unlink
# operation because it failed to realize they were different files.
rm -f $SCRATCH_MNT/mysnap2/foo/bar
$XFS_IO_PROG -f -c "pwrite -S 0xbb 0 96K" \
$SCRATCH_MNT/mysnap2/foo/bar | _filter_xfs_io
_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT/mysnap2 \
$SCRATCH_MNT/mysnap2_ro
_run_btrfs_util_prog send $SCRATCH_MNT/mysnap1 -f $send_files_dir/1.snap
_run_btrfs_util_prog send -p $SCRATCH_MNT/mysnap1 \
$SCRATCH_MNT/mysnap2_ro -f $send_files_dir/2.snap
echo "File digest in the original filesystem after being replaced:"
md5sum $SCRATCH_MNT/mysnap2_ro/foo/bar | _filter_scratch
# Now recreate the filesystem by receiving both send streams and verify
# we get the same file contents that the original filesystem had.
_scratch_unmount
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
_run_btrfs_util_prog receive -vv $SCRATCH_MNT -f $send_files_dir/1.snap
_run_btrfs_util_prog receive -vv $SCRATCH_MNT -f $send_files_dir/2.snap
echo "File digest in the new filesystem:"
# Must match the digest from the new file.
md5sum $SCRATCH_MNT/mysnap2_ro/foo/bar | _filter_scratch
status=0
exit
Reported-by: Martin Raiber <martin@urbackup.org>
Fixes: 8b191a6849 ("Btrfs: incremental send, check if orphanized dir inode needs delayed rename")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
To avoid deadlock described in commit 084b6e7c76 ("btrfs: Fix a
lockdep warning when running xfstest."), we should move kobj stuff out
of dev_replace lock range.
"It is because the btrfs_kobj_{add/rm}_device() will call memory
allocation with GFP_KERNEL,
which may flush fs page cache to free space, waiting for it self to do
the commit, causing the deadlock.
To solve the problem, move btrfs_kobj_{add/rm}_device() out of the
dev_replace lock range, also involing split the
btrfs_rm_dev_replace_srcdev() function into remove and free parts.
Now only btrfs_rm_dev_replace_remove_srcdev() is called in dev_replace
lock range, and kobj_{add/rm} and btrfs_rm_dev_replace_free_srcdev() are
called out of the lock range."
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[added lockup description]
Signed-off-by: David Sterba <dsterba@suse.com>
Originally the message was not in a helper but ended up there. We should
print error messages from callers instead.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[reworded subject and changelog]
Signed-off-by: David Sterba <dsterba@suse.com>
By general rule of thumb there shouldn't be any way that user land
could trigger a kernel operation just by sending wrong arguments.
Here do commit cleanups after user input has been verified.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch updates and renames btrfs_scratch_superblocks, (which is used
by the replace device thread), with those fixes from the scratch
superblock code section of btrfs_rm_device(). The fixes are:
Scratch all copies of superblock
Notify kobject that superblock has been changed
Update time on the device
So that btrfs_rm_device() can use the function
btrfs_scratch_superblocks() instead of its own scratch code. And further
replace deivce code which similarly releases device back to the system,
will have the fixes from the btrfs device delete.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[renamed to btrfs_scratch_superblock]
Signed-off-by: David Sterba <dsterba@suse.com>
This uses a chunk of code from btrfs_read_dev_super() and creates
a function called btrfs_read_dev_one_super() so that next patch
can use it for scratch superblock.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[renamed bufhead to bh]
Signed-off-by: David Sterba <dsterba@suse.com>
Use btrfs specific error code BTRFS_ERROR_DEV_MISSING_NOT_FOUND instead
of -ENOENT. Next this removes the logging when user specifies "missing"
and we don't find it in the kernel device list. Logging are for system
events not for user input errors.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_error() and btrfs_std_error() does the same thing
and calls _btrfs_std_error(), so consolidate them together.
And the main motivation is that btrfs_error() is closely
named with btrfs_err(), one handles error action the other
is to log the error, so don't closely name them.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Suggested-by: David Sterba <dsterba@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
error handling logic behaves differently with or without
CONFIG_PRINTK defined, since there are two copies of the same
function which a bit of different logic
One, when CONFIG_PRINTK is defined, code is
__btrfs_std_error(..)
{
::
save_error_info(fs_info);
if (sb->s_flags & MS_BORN)
btrfs_handle_error(fs_info);
}
and two when CONFIG_PRINTK is not defined, the code is
__btrfs_std_error(..)
{
::
if (sb->s_flags & MS_BORN) {
save_error_info(fs_info);
btrfs_handle_error(fs_info);
}
}
I doubt if this was intentional ? and appear to have caused since
we maintain two copies of the same function and they got diverged
with commits.
Now to decide which logic is correct reviewed changes as below,
533574c6bc
Commit added two copies of this function
cf79ffb5b7
Commit made change to only one copy of the function and to the
copy when CONFIG_PRINTK is defined.
To fix this, instead of maintaining two copies of same function
approach, maintain single function, and just put the extra
portion of the code under CONFIG_PRINTK define.
This patch just does that. And keeps code of with CONFIG_PRINTK
defined.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This will return EIO when __bread() fails to read SB,
instead of EINVAL.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from Chris Mason:
"This is an assorted set I've been queuing up:
Jeff Mahoney tracked down a tricky one where we ended up starting IO
on the wrong mapping for special files in btrfs_evict_inode. A few
people reported this one on the list.
Filipe found (and provided a test for) a difficult bug in reading
compressed extents, and Josef fixed up some quota record keeping with
snapshot deletion. Chandan killed off an accounting bug during DIO
that lead to WARN_ONs as we freed inodes"
* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: keep dropped roots in cache until transaction commit
Btrfs: Direct I/O: Fix space accounting
btrfs: skip waiting on ordered range for special files
Btrfs: fix read corruption of compressed and shared extents
Btrfs: remove unnecessary locking of cleaner_mutex to avoid deadlock
Btrfs: don't initialize a space info as full to prevent ENOSPC
When dropping a snapshot we need to account for the qgroup changes. If we drop
the snapshot in all one go then the backref code will fail to find blocks from
the snapshot we dropped since it won't be able to find the root in the fs root
cache. This can lead to us failing to find refs from other roots that pointed
at blocks in the now deleted root. To handle this we need to not remove the fs
roots from the cache until after we process the qgroup operations. Do this by
adding dropped roots to a list on the transaction, and letting the transaction
remove the roots at the same time it drops the commit roots. This will keep all
of the backref searching code in sync properly, and fixes a problem Mark was
seeing with snapshot delete and qgroups. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Tested-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Signed-off-by: Chris Mason <clm@fb.com>
The following call trace is seen when generic/095 test is executed,
WARNING: CPU: 3 PID: 2769 at /home/chandan/code/repos/linux/fs/btrfs/inode.c:8967 btrfs_destroy_inode+0x284/0x2a0()
Modules linked in:
CPU: 3 PID: 2769 Comm: umount Not tainted 4.2.0-rc5+ #31
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20150306_163512-brownie 04/01/2014
ffffffff81c08150 ffff8802ec9cbce8 ffffffff81984058 ffff8802ffd8feb0
0000000000000000 ffff8802ec9cbd28 ffffffff81050385 ffff8802ec9cbd38
ffff8802d12f8588 ffff8802d12f8588 ffff8802f15ab000 ffff8800bb96c0b0
Call Trace:
[<ffffffff81984058>] dump_stack+0x45/0x57
[<ffffffff81050385>] warn_slowpath_common+0x85/0xc0
[<ffffffff81050465>] warn_slowpath_null+0x15/0x20
[<ffffffff81340294>] btrfs_destroy_inode+0x284/0x2a0
[<ffffffff8117ce07>] destroy_inode+0x37/0x60
[<ffffffff8117cf39>] evict+0x109/0x170
[<ffffffff8117cfd5>] dispose_list+0x35/0x50
[<ffffffff8117dd3a>] evict_inodes+0xaa/0x100
[<ffffffff81165667>] generic_shutdown_super+0x47/0xf0
[<ffffffff81165951>] kill_anon_super+0x11/0x20
[<ffffffff81302093>] btrfs_kill_super+0x13/0x110
[<ffffffff81165c99>] deactivate_locked_super+0x39/0x70
[<ffffffff811660cf>] deactivate_super+0x5f/0x70
[<ffffffff81180e1e>] cleanup_mnt+0x3e/0x90
[<ffffffff81180ebd>] __cleanup_mnt+0xd/0x10
[<ffffffff81069c06>] task_work_run+0x96/0xb0
[<ffffffff81003a3d>] do_notify_resume+0x3d/0x50
[<ffffffff8198cbc2>] int_signal+0x12/0x17
This means that the inode had non-zero "outstanding extents" during
eviction. This occurs because, during direct I/O a task which successfully
used up its reserved data space would set BTRFS_INODE_DIO_READY bit and does
not clear the bit after finishing the DIO write. A future DIO write could
actually fail and the unused reserve space won't be freed because of the
previously set BTRFS_INODE_DIO_READY bit.
Clearing the BTRFS_INODE_DIO_READY bit in btrfs_direct_IO() caused the
following issue,
|-----------------------------------+-------------------------------------|
| Task A | Task B |
|-----------------------------------+-------------------------------------|
| Start direct i/o write on inode X.| |
| reserve space | |
| Allocate ordered extent | |
| release reserved space | |
| Set BTRFS_INODE_DIO_READY bit. | |
| | splice() |
| | Transfer data from pipe buffer to |
| | destination file. |
| | - kmap(pipe buffer page) |
| | - Start direct i/o write on |
| | inode X. |
| | - reserve space |
| | - dio_refill_pages() |
| | - sdio->blocks_available == 0 |
| | - Since a kernel address is |
| | being passed instead of a |
| | user space address, |
| | iov_iter_get_pages() returns |
| | -EFAULT. |
| | - Since BTRFS_INODE_DIO_READY is |
| | set, we don't release reserved |
| | space. |
| | - Clear BTRFS_INODE_DIO_READY bit.|
| -EIOCBQUEUED is returned. | |
|-----------------------------------+-------------------------------------|
Hence this commit introduces "struct btrfs_dio_data" to track the usage of
reserved data space. The remaining unused "reserve space" can now be freed
reliably.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
In btrfs_evict_inode, we properly truncate the page cache for evicted
inodes but then we call btrfs_wait_ordered_range for every inode as well.
It's the right thing to do for regular files but results in incorrect
behavior for device inodes for block devices.
filemap_fdatawrite_range gets called with inode->i_mapping which gets
resolved to the block device inode before getting passed to
wbc_attach_fdatawrite_inode and ultimately to inode_to_bdi. What happens
next depends on whether there's an open file handle associated with the
inode. If there is, we write to the block device, which is unexpected
behavior. If there isn't, we through normally and inode->i_data is used.
We can also end up racing against open/close which can result in crashes
when i_mapping points to a block device inode that has been closed.
Since there can't be any page cache associated with special file inodes,
it's safe to skip the btrfs_wait_ordered_range call entirely and avoid
the problem.
Cc: <stable@vger.kernel.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=100911
Tested-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
If a file has a range pointing to a compressed extent, followed by
another range that points to the same compressed extent and a read
operation attempts to read both ranges (either completely or part of
them), the pages that correspond to the second range are incorrectly
filled with zeroes.
Consider the following example:
File layout
[0 - 8K] [8K - 24K]
| |
| |
points to extent X, points to extent X,
offset 4K, length of 8K offset 0, length 16K
[extent X, compressed length = 4K uncompressed length = 16K]
If a readpages() call spans the 2 ranges, a single bio to read the extent
is submitted - extent_io.c:submit_extent_page() would only create a new
bio to cover the second range pointing to the extent if the extent it
points to had a different logical address than the extent associated with
the first range. This has a consequence of the compressed read end io
handler (compression.c:end_compressed_bio_read()) finish once the extent
is decompressed into the pages covering the first range, leaving the
remaining pages (belonging to the second range) filled with zeroes (done
by compression.c:btrfs_clear_biovec_end()).
So fix this by submitting the current bio whenever we find a range
pointing to a compressed extent that was preceded by a range with a
different extent map. This is the simplest solution for this corner
case. Making the end io callback populate both ranges (or more, if we
have multiple pointing to the same extent) is a much more complex
solution since each bio is tightly coupled with a single extent map and
the extent maps associated to the ranges pointing to the shared extent
can have different offsets and lengths.
The following test case for fstests triggers the issue:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_need_to_be_root
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_cloner
rm -f $seqres.full
test_clone_and_read_compressed_extent()
{
local mount_opts=$1
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount $mount_opts
# Create a test file with a single extent that is compressed (the
# data we write into it is highly compressible no matter which
# compression algorithm is used, zlib or lzo).
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 4K" \
-c "pwrite -S 0xbb 4K 8K" \
-c "pwrite -S 0xcc 12K 4K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Now clone our extent into an adjacent offset.
$CLONER_PROG -s $((4 * 1024)) -d $((16 * 1024)) -l $((8 * 1024)) \
$SCRATCH_MNT/foo $SCRATCH_MNT/foo
# Same as before but for this file we clone the extent into a lower
# file offset.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 8K 4K" \
-c "pwrite -S 0xbb 12K 8K" \
-c "pwrite -S 0xcc 20K 4K" \
$SCRATCH_MNT/bar | _filter_xfs_io
$CLONER_PROG -s $((12 * 1024)) -d 0 -l $((8 * 1024)) \
$SCRATCH_MNT/bar $SCRATCH_MNT/bar
echo "File digests before unmounting filesystem:"
md5sum $SCRATCH_MNT/foo | _filter_scratch
md5sum $SCRATCH_MNT/bar | _filter_scratch
# Evicting the inode or clearing the page cache before reading
# again the file would also trigger the bug - reads were returning
# all bytes in the range corresponding to the second reference to
# the extent with a value of 0, but the correct data was persisted
# (it was a bug exclusively in the read path). The issue happened
# only if the same readpages() call targeted pages belonging to the
# first and second ranges that point to the same compressed extent.
_scratch_remount
echo "File digests after mounting filesystem again:"
# Must match the same digests we got before.
md5sum $SCRATCH_MNT/foo | _filter_scratch
md5sum $SCRATCH_MNT/bar | _filter_scratch
}
echo -e "\nTesting with zlib compression..."
test_clone_and_read_compressed_extent "-o compress=zlib"
_scratch_unmount
echo -e "\nTesting with lzo compression..."
test_clone_and_read_compressed_extent "-o compress=lzo"
status=0
exit
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo<quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Pull btrfs cleanups and fixes from Chris Mason:
"These are small cleanups, and also some fixes for our async worker
thread initialization.
I was having some trouble testing these, but it ended up being a
combination of changing around my test servers and a shiny new
schedule while atomic from the new start/finish_plug in
writeback_sb_inodes().
That one only hits on btrfs raid5/6 or MD raid10, and if I wasn't
changing a bunch of things in my test setup at once it would have been
really clear. Fix for writeback_sb_inodes() on the way as well"
* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: cleanup: remove unnecessary check before btrfs_free_path is called
btrfs: async_thread: Fix workqueue 'max_active' value when initializing
btrfs: Add raid56 support for updating num_tolerated_disk_barrier_failures in btrfs_balance
btrfs: Cleanup for btrfs_calc_num_tolerated_disk_barrier_failures
btrfs: Remove noused chunk_tree and chunk_objectid from scrub_enumerate_chunks and scrub_chunk
btrfs: Update out-of-date "skip parity stripe" comment
After commmit e44163e177 ("btrfs: explictly delete unused block groups
in close_ctree and ro-remount"), added in the 4.3 merge window, we have
calls to btrfs_delete_unused_bgs() while holding the cleaner_mutex.
This can cause a deadlock with a concurrent block group relocation (when
a filesystem balance or shrink operation is in progress for example)
because btrfs_delete_unused_bgs() locks delete_unused_bgs_mutex and the
relocation path locks first delete_unused_bgs_mutex and then it locks
cleaner_mutex, resulting in a classic ABBA deadlock:
CPU 0 CPU 1
lock fs_info->cleaner_mutex
__btrfs_balance() || btrfs_shrink_device()
lock fs_info->delete_unused_bgs_mutex
btrfs_relocate_chunk()
btrfs_relocate_block_group()
lock fs_info->cleaner_mutex
btrfs_delete_unused_bgs()
lock fs_info->delete_unused_bgs_mutex
Fix this by not taking the cleaner_mutex before calling
btrfs_delete_unused_bgs() because it's no longer needed after
commit 67c5e7d464 ("Btrfs: fix race between balance and unused block
group deletion"). The mutex fs_info->delete_unused_bgs_mutex, the
spinlock fs_info->unused_bgs_lock and a block group's spinlock are
enough to get correct serialization between tasks running relocation
and unused block group deletion (as well as between multiple tasks
concurrently calling btrfs_delete_unused_bgs()).
This issue was discussed (in the mailing list) during the review of
the patch titled "btrfs: explictly delete unused block groups in
close_ctree and ro-remount" and it was agreed that acquiring the
cleaner mutex had to be dropped after the patch titled
"Btrfs: fix race between balance and unused block group deletion"
got merged (both patches were submitted at about the same time, but
one landed in kernel 4.2 and the other in the 4.3 merge window).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Commit 2e6e518335 ("Btrfs: fix block group ->space_info null pointer
dereference") accidently marked a space info as full when initializing
it with a value of 0 total bytes. This introduces an ENOSPC problem when
writing file data if we mount a filesystem that has no data block groups
allocated, because the data space info is initialized with 0 total bytes,
marked as full, and it never gets its total bytes incremented by a
(positive) value to unmark it as full (because there are no data block
groups loaded when the fs is mounted).
For metadata and system spaces this issue can never happen since we always
have at least one metadata block group and one system block group (even
for an empty filesystem).
So fix this by just not initializing a space info as full, reverting the
offending part of the commit mentioned above.
The following test case for fstests reproduces the issue:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_need_to_be_root
_supported_fs btrfs
_supported_os Linux
_require_scratch
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
# Mount our filesystem without space caches enabled so that we do not
# get any space used from the initial data block group that mkfs creates
# (space caches used space from data block groups).
_scratch_mount "-o nospace_cache"
# Need an fs with at least 2Gb to make sure mkfs.btrfs does not create
# an fs using mixed block groups (used both for data and metadata). We
# really need to have dedicated block groups for data to reproduce the
# issue and mkfs.btrfs defaults to mixed block groups only for small
# filesystems (up to 1Gb).
_require_fs_space $SCRATCH_MNT $((2 * 1024 * 1024))
# Run balance with the purpose of deleting the unused data block group
# that mkfs created. We could also wait for the background kthread to
# automatically delete the unused block group, but we do not have a way
# to make it run and wait for it to complete, so just do a balance
# instead of some unreliable sleep
_run_btrfs_util_prog balance start -dusage=0 $SCRATCH_MNT
# Now unmount the filesystem, mount it again (either with or with space
# caches enabled, it does not matter to trigger the problem) and attempt
# to create a file with some data - this used to fail with ENOSPC
# because there were no data block groups when the filesystem was
# mounted and the data space info object was marked as full when
# initialized (because it had 0 total bytes), which prevented the file
# write path from attempting to allocate a data block group and fail
# immediately with ENOSPC.
_scratch_remount
echo "hello world" > $SCRATCH_MNT/foobar
echo "Silence is golden"
status=0
exit
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Pull vfs updates from Al Viro:
"In this one:
- d_move fixes (Eric Biederman)
- UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
handling ought to be fixed)
- switch of sb_writers to percpu rwsem (Oleg Nesterov)
- superblock scalability (Josef Bacik and Dave Chinner)
- swapon(2) race fix (Hugh Dickins)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
vfs: Test for and handle paths that are unreachable from their mnt_root
dcache: Reduce the scope of i_lock in d_splice_alias
dcache: Handle escaped paths in prepend_path
mm: fix potential data race in SyS_swapon
inode: don't softlockup when evicting inodes
inode: rename i_wb_list to i_io_list
sync: serialise per-superblock sync operations
inode: convert inode_sb_list_lock to per-sb
inode: add hlist_fake to avoid the inode hash lock in evict
writeback: plug writeback at a high level
change sb_writers to use percpu_rw_semaphore
shift percpu_counter_destroy() into destroy_super_work()
percpu-rwsem: kill CONFIG_PERCPU_RWSEM
percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
percpu-rwsem: introduce percpu_down_read_trylock()
document rwsem_release() in sb_wait_write()
fix the broken lockdep logic in __sb_start_write()
introduce __sb_writers_{acquired,release}() helpers
ufs_inode_get{frag,block}(): get rid of 'phys' argument
ufs_getfrag_block(): tidy up a bit
...
Pull btrfs updates from Chris Mason:
"This has Jeff Mahoney's long standing trim patch that fixes corners
where trims were missing. Omar has some raid5/6 fixes, especially for
using scrub and device replace when devices are missing.
Zhao Lie continues cleaning and fixing things, this series fixes some
really hard to hit corners in xfstests. I had to pull it last merge
window due to some deadlocks, but those are now resolved.
I added support for Tejun's new blkio controllers. It seems to work
well for single devices, we'll expand to multi-device as well"
* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (47 commits)
btrfs: fix compile when block cgroups are not enabled
Btrfs: fix file read corruption after extent cloning and fsync
Btrfs: check if previous transaction aborted to avoid fs corruption
btrfs: use __GFP_NOFAIL in alloc_btrfs_bio
btrfs: Prevent from early transaction abort
btrfs: Remove unused arguments in tree-log.c
btrfs: Remove useless condition in start_log_trans()
Btrfs: add support for blkio controllers
Btrfs: remove unused mutex from struct 'btrfs_fs_info'
Btrfs: fix parity scrub of RAID 5/6 with missing device
Btrfs: fix device replace of a missing RAID 5/6 device
Btrfs: add RAID 5/6 BTRFS_RBIO_REBUILD_MISSING operation
Btrfs: count devices correctly in readahead during RAID 5/6 replace
Btrfs: remove misleading handling of missing device scrub
btrfs: fix clone / extent-same deadlocks
Btrfs: fix defrag to merge tail file extent
Btrfs: fix warning in backref walking
btrfs: Add WARN_ON() for double lock in btrfs_tree_lock()
btrfs: Remove root argument in extent_data_ref_count()
btrfs: Fix wrong comment of btrfs_alloc_tree_block()
...
Pull core block updates from Jens Axboe:
"This first core part of the block IO changes contains:
- Cleanup of the bio IO error signaling from Christoph. We used to
rely on the uptodate bit and passing around of an error, now we
store the error in the bio itself.
- Improvement of the above from myself, by shrinking the bio size
down again to fit in two cachelines on x86-64.
- Revert of the max_hw_sectors cap removal from a revision again,
from Jeff Moyer. This caused performance regressions in various
tests. Reinstate the limit, bump it to a more reasonable size
instead.
- Make /sys/block/<dev>/queue/discard_max_bytes writeable, by me.
Most devices have huge trim limits, which can cause nasty latencies
when deleting files. Enable the admin to configure the size down.
We will look into having a more sane default instead of UINT_MAX
sectors.
- Improvement of the SGP gaps logic from Keith Busch.
- Enable the block core to handle arbitrarily sized bios, which
enables a nice simplification of bio_add_page() (which is an IO hot
path). From Kent.
- Improvements to the partition io stats accounting, making it
faster. From Ming Lei.
- Also from Ming Lei, a basic fixup for overflow of the sysfs pending
file in blk-mq, as well as a fix for a blk-mq timeout race
condition.
- Ming Lin has been carrying Kents above mentioned patches forward
for a while, and testing them. Ming also did a few fixes around
that.
- Sasha Levin found and fixed a use-after-free problem introduced by
the bio->bi_error changes from Christoph.
- Small blk cgroup cleanup from Viresh Kumar"
* 'for-4.3/core' of git://git.kernel.dk/linux-block: (26 commits)
blk: Fix bio_io_vec index when checking bvec gaps
block: Replace SG_GAPS with new queue limits mask
block: bump BLK_DEF_MAX_SECTORS to 2560
Revert "block: remove artifical max_hw_sectors cap"
blk-mq: fix race between timeout and freeing request
blk-mq: fix buffer overflow when reading sysfs file of 'pending'
Documentation: update notes in biovecs about arbitrarily sized bios
block: remove bio_get_nr_vecs()
fs: use helper bio_add_page() instead of open coding on bi_io_vec
block: kill merge_bvec_fn() completely
md/raid5: get rid of bio_fits_rdev()
md/raid5: split bio for chunk_aligned_read
block: remove split code in blkdev_issue_{discard,write_same}
btrfs: remove bio splitting and merge_bvec_fn() calls
bcache: remove driver private bio splitting code
block: simplify bio_add_page()
block: make generic_make_request handle arbitrarily sized bios
blk-cgroup: Drop unlikely before IS_ERR(_OR_NULL)
block: don't access bio->bi_error after bio_put()
block: shrink struct bio down to 2 cache lines again
...
We need not check path before btrfs_free_path() is called because
path is checked in btrfs_free_path().
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
At initializing time, for threshold-able workqueue, it's max_active
of kernel workqueue should be 1 and grow if it hits threshold.
But due to the bad naming, there is both 'max_active' for kernel
workqueue and btrfs workqueue.
So wrong value is given at workqueue initialization.
This patch fixes it, and to avoid further misunderstanding, change the
member name of btrfs_workqueue to 'current_active' and 'limit_active'.
Also corresponding comment is added for readability.
Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
num_tolerated_disk_barrier_failures in btrfs_balance
Code for updating fs_info->num_tolerated_disk_barrier_failures in
btrfs_balance() lacks raid56 support.
Reason:
Above code was wroten in 2012-08-01, together with
btrfs_calc_num_tolerated_disk_barrier_failures()'s first version.
Then, btrfs_calc_num_tolerated_disk_barrier_failures() got updated
later to support raid56, but code in btrfs_balance() was not
updated together.
Fix:
Merge above similar code to a common function:
btrfs_get_num_tolerated_disk_barrier_failures()
and make it support both case.
It can fix this bug with a bonus of cleanup, and make these code
never in above no-sync state from now on.
Suggested-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
1: Use ARRAY_SIZE(types) to replace a static-value variant:
int num_types = 4;
2: Use 'continue' on condition to reduce one level tab
if (!XXX) {
code;
...
}
->
if (XXX)
continue;
code;
...
3: Put setting 'num_tolerated_disk_barrier_failures = 2' to
(num_tolerated_disk_barrier_failures > 2) condition to make
make logic neat.
if (num_tolerated_disk_barrier_failures > 0 && XXX)
num_tolerated_disk_barrier_failures = 0;
else if (num_tolerated_disk_barrier_failures > 1) {
if (XXX)
num_tolerated_disk_barrier_failures = 1;
else if (XXX)
num_tolerated_disk_barrier_failures = 2;
->
if (num_tolerated_disk_barrier_failures > 0 && XXX)
num_tolerated_disk_barrier_failures = 0;
if (num_tolerated_disk_barrier_failures > 1 && XXX)
num_tolerated_disk_barrier_failures = ;
if (num_tolerated_disk_barrier_failures > 2 && XXX)
num_tolerated_disk_barrier_failures = 2;
4: Remove comment of:
num_mirrors - 1: if RAID1 or RAID10 is configured and more
than 2 mirrors are used.
which is not fit with code.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
These variables are not used from introduced version, remove them.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
bio->bi_css and bio->bi_ioc don't exist when block cgroups are not on.
This adds an ifdef around them. It's not perfect, but our
use of bi_ioc is being removed in the 4.3 merge window.
The bi_css usage really should go into bio_clone, but I want to make
sure that doesn't introduce problems for other bio_clone use cases.
Signed-off-by: Chris Mason <clm@fb.com>
If we partially clone one extent of a file into a lower offset of the
file, fsync the file, power fail and then mount the fs to trigger log
replay, we can get multiple checksum items in the csum tree that overlap
each other and result in checksum lookup failures later. Those failures
can make file data read requests assume a checksum value of 0, but they
will not return an error (-EIO for example) to userspace exactly because
the expected checksum value 0 is a special value that makes the read bio
endio callback return success and set all the bytes of the corresponding
page with the value 0x01 (at fs/btrfs/inode.c:__readpage_endio_check()).
From a userspace perspective this is equivalent to file corruption
because we are not returning what was written to the file.
Details about how this can happen, and why, are included inline in the
following reproducer test case for fstests and the comment added to
tree-log.c.
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
_cleanup_flakey
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
# real QA test starts here
_need_to_be_root
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_dm_flakey
_require_cloner
_require_metadata_journaling $SCRATCH_DEV
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test file with a single 100K extent starting at file
# offset 800K. We fsync the file here to make the fsync log tree gets
# a single csum item that covers the whole 100K extent, which causes
# the second fsync, done after the cloning operation below, to not
# leave in the log tree two csum items covering two sub-ranges
# ([0, 20K[ and [20K, 100K[)) of our extent.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 800K 100K" \
-c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Now clone part of our extent into file offset 400K. This adds a file
# extent item to our inode's metadata that points to the 100K extent
# we created before, using a data offset of 20K and a data length of
# 20K, so that it refers to the sub-range [20K, 40K[ of our original
# extent.
$CLONER_PROG -s $((800 * 1024 + 20 * 1024)) -d $((400 * 1024)) \
-l $((20 * 1024)) $SCRATCH_MNT/foo $SCRATCH_MNT/foo
# Now fsync our file to make sure the extent cloning is durably
# persisted. This fsync will not add a second csum item to the log
# tree containing the checksums for the blocks in the sub-range
# [20K, 40K[ of our extent, because there was already a csum item in
# the log tree covering the whole extent, added by the first fsync
# we did before.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
echo "File digest before power failure:"
md5sum $SCRATCH_MNT/foo | _filter_scratch
# Silently drop all writes and ummount to simulate a crash/power
# failure.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again, mount to trigger log replay and validate file
# contents.
# The fsync log replay first processes the file extent item
# corresponding to the file offset 400K (the one which refers to the
# [20K, 40K[ sub-range of our 100K extent) and then processes the file
# extent item for file offset 800K. It used to happen that when
# processing the later, it erroneously left in the csum tree 2 csum
# items that overlapped each other, 1 for the sub-range [20K, 40K[ and
# 1 for the whole range of our extent. This introduced a problem where
# subsequent lookups for the checksums of blocks within the range
# [40K, 100K[ of our extent would not find anything because lookups in
# the csum tree ended up looking only at the smaller csum item, the
# one covering the subrange [20K, 40K[. This made read requests assume
# an expected checksum with a value of 0 for those blocks, which caused
# checksum verification failure when the read operations finished.
# However those checksum failure did not result in read requests
# returning an error to user space (like -EIO for e.g.) because the
# expected checksum value had the special value 0, and in that case
# btrfs set all bytes of the corresponding pages with the value 0x01
# and produce the following warning in dmesg/syslog:
#
# "BTRFS warning (device dm-0): csum failed ino 257 off 917504 csum\
# 1322675045 expected csum 0"
#
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
echo "File digest after log replay:"
# Must match the same digest he had after cloning the extent and
# before the power failure happened.
md5sum $SCRATCH_MNT/foo | _filter_scratch
_unmount_flakey
status=0
exit
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
While we are committing a transaction, it's possible the previous one is
still finishing its commit and therefore we wait for it to finish first.
However we were not checking if that previous transaction ended up getting
aborted after we waited for it to commit, so we ended up committing the
current transaction which can lead to fs corruption because the new
superblock can point to trees that have had one or more nodes/leafs that
were never durably persisted.
The following sequence diagram exemplifies how this is possible:
CPU 0 CPU 1
transaction N starts
(...)
btrfs_commit_transaction(N)
cur_trans->state = TRANS_STATE_COMMIT_START;
(...)
cur_trans->state = TRANS_STATE_COMMIT_DOING;
(...)
cur_trans->state = TRANS_STATE_UNBLOCKED;
root->fs_info->running_transaction = NULL;
btrfs_start_transaction()
--> starts transaction N + 1
btrfs_write_and_wait_transaction(trans, root);
--> starts writing all new or COWed ebs created
at transaction N
creates some new ebs, COWs some
existing ebs but doesn't COW or
deletes eb X
btrfs_commit_transaction(N + 1)
(...)
cur_trans->state = TRANS_STATE_COMMIT_START;
(...)
wait_for_commit(root, prev_trans);
--> prev_trans == transaction N
btrfs_write_and_wait_transaction() continues
writing ebs
--> fails writing eb X, we abort transaction N
and set bit BTRFS_FS_STATE_ERROR on
fs_info->fs_state, so no new transactions
can start after setting that bit
cleanup_transaction()
btrfs_cleanup_one_transaction()
wakes up task at CPU 1
continues, doesn't abort because
cur_trans->aborted (transaction N + 1)
is zero, and no checks for bit
BTRFS_FS_STATE_ERROR in fs_info->fs_state
are made
btrfs_write_and_wait_transaction(trans, root);
--> succeeds, no errors during writeback
write_ctree_super(trans, root, 0);
--> succeeds
--> we have now a superblock that points us
to some root that uses eb X, which was
never written to disk
In this scenario future attempts to read eb X from disk results in an
error message like "parent transid verify failed on X wanted Y found Z".
So fix this by aborting the current transaction if after waiting for the
previous transaction we verify that it was aborted.
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
alloc_btrfs_bio relies on GFP_NOFS allocation when committing the
transaction but this allocation context is rather weak wrt. reclaim
capabilities. The page allocator currently tries hard to not fail these
allocations if they are small (<=PAGE_ALLOC_COSTLY_ORDER) but it can
still fail if the _current_ process is the OOM killer victim. Moreover
there is an attempt to move away from the default no-fail behavior and
allow these allocation to fail more eagerly. This would lead to:
[ 37.928625] kernel BUG at fs/btrfs/extent_io.c:4045
which is clearly undesirable and the nofail behavior should be explicit
if the allocation failure cannot be tolerated.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Following arguments are not used in tree-log.c:
insert_one_name(): path, type
wait_log_commit(): trans
wait_for_writer(): trans
This patch remove them.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Dan Carpenter <dan.carpenter@oracle.com> reported a smatch warning
for start_log_trans():
fs/btrfs/tree-log.c:178 start_log_trans()
warn: we tested 'root->log_root' before and it was 'false'
fs/btrfs/tree-log.c
147 if (root->log_root) {
We test "root->log_root" here.
...
Reason:
Condition of:
fs/btrfs/tree-log.c:178: if (!root->log_root) {
is not necessary after commit: 7237f1833
It caused a smatch warning, and no functionally error.
Fix:
Deleting above condition will make smatch shut up,
but a better way is to do cleanup for start_log_trans()
to remove duplicated code and make code more readable.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Preparation to hide the sb->s_writers internals from xfs and btrfs.
Add 2 trivial define's they can use rather than play with ->s_writers
directly. No changes in btrfs/transaction.o and xfs/xfs_aops.o.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jan Kara <jack@suse.com>
We can always fill up the bio now, no need to estimate the possible
size based on queue parameters.
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[hch: rebased and wrote a changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Btrfs has been doing bio splitting from btrfs_map_bio(), by checking
device limits as well as calling ->merge_bvec_fn() etc. That is not
necessary any more, because generic_make_request() is now able to
handle arbitrarily sized bios. So clean up unnecessary code paths.
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dpark@posteo.net>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This attaches accounting information to bios as we submit them so the
new blkio controllers can throttle on btrfs filesystems.
Not much is required, we're just associating bios with blkcgs during clone,
calling wbc_init_bio()/wbc_account_io() during writepages submission,
and attaching the bios to the current context during direct IO.
Finally if we are splitting bios during btrfs_map_bio, this attaches
accounting information to the split.
The end result is able to throttle nicely on single disk filesystems. A
little more work is required for multi-device filesystems.
Signed-off-by: Chris Mason <clm@fb.com>
The code using 'ordered_extent_flush_mutex' mutex has removed by below
commit.
- 8d875f95da
btrfs: disable strict file flushes for renames and truncates
But the mutex still lives in struct 'btrfs_fs_info'.
So, this patch removes the mutex from struct 'btrfs_fs_info' and its
initialization code.
Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When testing the previous patch, Zhao Lei reported a similar bug when
attempting to scrub a degraded RAID 5/6 filesystem with a missing
device, leading to NULL pointer dereferences from the RAID 5/6 parity
scrubbing code.
The first cause was the same as in the previous patch: attempting to
call bio_add_page() on a missing block device. To fix this,
scrub_extent_for_parity() can just mark the sectors on the missing
device as errors instead of attempting to read from it.
Additionally, the code uses scrub_remap_extent() to map the extent of
the corresponding data stripe, but the extent wasn't already mapped. If
scrub_remap_extent() finds a missing block device, it doesn't initialize
extent_dev, so we're left with a NULL struct btrfs_device. The solution
is to use btrfs_map_block() directly.
Reported-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The original implementation of device replace on RAID 5/6 seems to have
missed support for replacing a missing device. When this is attempted,
we end up calling bio_add_page() on a bio with a NULL ->bi_bdev, which
crashes when we try to dereference it. This happens because
btrfs_map_block() has no choice but to return us the missing device
because RAID 5/6 don't have any alternate mirrors to read from, and a
missing device has a NULL bdev.
The idea implemented here is to handle the missing device case
separately, which better only happen when we're replacing a missing RAID
5/6 device. We use the new BTRFS_RBIO_REBUILD_MISSING operation to
reconstruct the data from parity, check it with
scrub_recheck_block_checksum(), and write it out with
scrub_write_block_to_dev_replace().
Reported-by: Philip <bugzilla@philip-seeger.de>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=96141
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The current RAID 5/6 recovery code isn't quite prepared to handle
missing devices. In particular, it expects a bio that we previously
attempted to use in the read path, meaning that it has valid pages
allocated. However, missing devices have a NULL blkdev, and we can't
call bio_add_page() on a bio with a NULL blkdev. We could do manual
manipulation of bio->bi_io_vec, but that's pretty gross. So instead, add
a separate path that allows us to manually add pages to the rbio.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit 5fbc7c59fd ("Btrfs: fix unfinished readahead thread for raid5/6
degraded mounting") fixed a problem where we would skip a missing device
when we shouldn't have because there are no other mirrors to read from
in RAID 5/6. After commit 2c8cdd6ee4 ("Btrfs, replace: write dirty
pages into the replace target device"), the fix doesn't work when we're
doing a missing device replace on RAID 5/6 because the replace device is
counted as a mirror so we're tricked into thinking we can safely skip
the missing device. The fix is to count only the real stripes and decide
based on that.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
scrub_submit() claims that it can handle a bio with a NULL block device,
but this is misleading, as calling bio_add_page() on a bio with a NULL
->bi_bdev would've already crashed. Delete this, as we're about to
properly handle a missing block device.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Clone and extent same lock their source and target inodes in opposite order.
In addition to this, the range locking in clone doesn't take ordering into
account. Fix this by having clone use the same locking helpers as
btrfs-extent-same.
In addition, I do a small cleanup of the locking helpers, removing a case
(both inodes being the same) which was poorly accounted for and never
actually used by the callers.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The file layout is
[extent 1]...[extent n][4k extent][HOLE][extent x]
extent 1~n and 4k extent can be merged during defrag, and the whole
defrag bytes is larger than our defrag thresh(256k), 4k extent as a
tail is left unmerged since we check if its next extent can be merged
(the next one is a hole, so the check will fail), the layout thus can
be
[new extent][4k extent][HOLE][extent x]
(1~n)
To fix it, beside looking at the next one, this also looks at the
previous one by checking @defrag_end, which is set to 0 when we
decide to stop merging contiguous extents, otherwise, we can merge
the previous one with our extent.
Also, this makes btrfs behave consistent with how xfs and ext4 do.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we do backref walking, we search firstly in queued delayed refs
and then the on-disk backrefs, but we parse differently for shared
references, for delayed refs we also add 'ref->root' while for on-disk
backrefs we don't, this can prevent us from merging refs indexed
by the same bytenr and cause find_parent_nodes() to throw a warning at
'WARN_ON(ref->count < 0)', for example, when we have a shared data extent
with 'ref_cnt=1' and a delayed shared data with a BTRFS_DROP_DELAYED_REF,
that happens.
For shared references, no matter if it's delayed or on-disk, ref->root is
not at all used, instead it's ref->parent that really matters, so this has
delayed refs handled as the same way as on-disk refs.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
When a task trying to double lock a extent buffer, there are no
lockdep warning about it because this lock may be in "blocking_lock"
state, and make us hard to debug.
This patch add a WARN_ON() for above condition, it can not report
all deadlock cases(as lock between tasks), but at least helps us
some.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
These wrong comment was copyed from another function(expired) from
init, this patch fixed them.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When btrfs_reloc_cow_block() failed in __btrfs_cow_block(), current
code just return a err-value to caller, but leave new_created extent
buffer exist and locked.
Then subsequent code (in relocate) try to lock above eb again,
and caused deadlock without any dmesg.
(eb lock use wait_event(), so no lockdep message)
It is hard to do recover work in __btrfs_cow_block() at this error
point, but we can abort transaction to avoid deadlock and operate on
unstable state.a
It also helps developer to find wrong place quickly.
(better than a frozen fs without any dmesg before patch)
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
These arguments are not used in functions, remove them for cleanup
and make kernel stack happy.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Remove chunk_objectid argument from btrfs_relocate_chunk() because
it is not necessary, it can also cleanup some code in caller for
prepare its value.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
objectid's init-value is not used in any case, remove it.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We need error checking code for get_ref_objectid_v0() in
relocate_block_group(), to avoid unpredictable result, especially
for accessing uninitialized value(when function failed) after
this line.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
xfstests btrfs/070 sometimes failed.
In my test machine, its fail rate is about 30%.
In another vm(vmware), its fail rate is about 50%.
Reason:
btrfs/070 do replace and defrag with fsstress simultaneously,
after above operation, checksum error is found by scrub.
Actually, it have no relationship with defrag operation, only
replace with fsstress can trigger this bug.
New data writen to target device have possibility rewrited by
old data from source device by replace code in debug, to avoid
above problem, we can set target block group to readonly in
replace period, so new data requested by other operation will
not write to same place with replace code.
Before patch(4.1-rc3):
30% failed in 100 xfstests.
After patch:
0% failed in 300 xfstests.
It also happened in btrfs/071 as it's another scrub with IO load tests.
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Use new intruduced scrub_pause_on/off() can make this code block
clean and more readable.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
It can reduce current duplicated code which is similar to
scrub_blocked_if_needed() but can not call it because little
different.
It also used by my next patch which is in same case.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
More than one code call set_block_group_ro() and restore rw in fail.
Old code use bool bit to save blockgroup's ro state, it can not
support parallel case(it is confirmd exist in my debug log).
This patch use ref count to store ro state, and rename
set_block_group_ro/set_block_group_rw
to
inc_block_group_ro/dec_block_group_ro.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we access extent_root in scrub_stripe() and
scrub_raid56_parity(), we need bypass unrelated tree item firstly
before using its contents to do other condition.
It is not a bug fix, only making code sequence in logic.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We need not load csum of whole strip in scrub because strip is trimed
before use, it is to say, what we really need to calculate csum is
data between [extent_logical, extent_len).
This patch changed to use above segment for btrfs_lookup_csums_range()
in scrub_stripe()
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
For example, in scrub_raid56_parity(), following lines are used
to judge is all data processed:
place1: if (key.objectid > logic_end) ...
place2: if (logic_start >= logic_end) ...
...
(place2 is typo, is should be ">", it is copied from other
place, where logic_end's meaning is different, long story...)
We can fix above typo directly, but the root reason is ambiguous
meaning of logic_end in scrub raid56 parity.
In other place, XXX_end is pointed to data which is not included,
and we need to process segment of [XXX_start, XXX_end).
But for scrub raid56 parity, logic_end is pointed to lattest data
need to process, and introduced many "+ 1" and "- 1" in code as
below:
length = sparity->logic_end - sparity->logic_start + 1
logic_end - logic_start + 1
stripe_logical + increment - 1
This patch changed logic_end's meaning to make it in normal understanding
in raid56 parity functions and data struct alone with above bugfix.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When scrub_extent() failed, we need to free previois created
checksum list.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Old code checking cancel and pause request inside scrub stripe
operation, like:
loop() {
if (parity) {
scrub_parity_stripe();
continue;
}
check_cancel_and_pause()
scrub_normal_stripe();
}
Reason is when introduce raid56 stripe scrub, new code is inserted
simplely to front of loop.
Better to:
loop() {
check_cancel_and_pause()
if (parity)
scrub_parity_stripe();
else
scrub_normal_stripe();
}
This patch adjusted code place to realize above sequence.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When mount failed because missing device, we can see following
dmesg:
[ 1060.267743] BTRFS: too many missing devices, writeable mount is not allowed
[ 1060.273158] BTRFS: open_ctree failed
This patch add missing_device_number and tolerated_missing_device_number
to above output, to let user know what really happened, and helps
bug-report and debug.
dmesg after patch:
[ 127.050367] BTRFS: missing devices(1) exceeds the limit(0), writeable mount is not allowed
[ 127.056099] BTRFS: open_ctree failed
Changelog v1->v2:
1: Changed to more clear description, suggested-by:
Anand Jain <anand.jain@oracle.com>
Suggested-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Scrub panic in following operation:
mkfs.ext4 /dev/vdh
btrfs-convert /dev/vdh
mount /dev/vdh /mnt/tmp1
btrfs scrub start -B /dev/vdh
(panic)
Reason:
1: In some case, leaf created by btrfs-convert was splited into 2
strips.
2: Scrub bypassed part of above wrong leaf data, but remain data
caused panic in scrub_checksum_tree_block().
For reason 1:
we can get following information after some simple operation.
a. mkfs.ext4 /dev/vdh
btrfs-convert /dev/vdh
b. btrfs-debug-tree /dev/vdh
we can see following item in extent tree:
item 25 key (27054080 METADATA_ITEM 0) itemoff 15083 itemsize 33
Its logical address is [27054080, 27070464)
and acrossed 2 strips:
[27000832, 27066368)
[27066368, 27131904)
Will be fixed in btrfs-progs(btrfs-convert, btrfsck, ...)
For reason 2:
Scrub is trying to do a "bypass" in this case, but the result is
"panic", because current code lacks of some condition in bypass,
and let some wrong leaf data escaped.
This patch fixed above scrub code.
Before patch:
# btrfs scrub start -B /dev/vdh
(panic)
After patch:
# btrfs scrub start -B /dev/vdh
scrub done for 353cec8f-da31-4a94-aa35-be72d997b06e
...
# dmesg
...
[ 59.088697] BTRFS error (device vdh): scrub: tree block 27054080 spanning stripes, ignored. logical=27000832
[ 59.089929] BTRFS error (device vdh): scrub: tree block 27054080 spanning stripes, ignored. logical=27066368
#
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We have one more case where after a log tree is replayed we get
inconsistent metadata leading to stale directory entries, due to
some directories having entries pointing to some inode while the
inode does not have a matching BTRFS_INODE_[REF|EXTREF]_KEY item.
To trigger the problem we need to have a file with multiple hard links
belonging to different parent directories. Then if one of those hard
links is removed and we fsync the file using one of its other links
that belongs to a different parent directory, we end up not logging
the fact that the removed hard link doesn't exists anymore in the
parent directory.
Simple reproducer:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
_cleanup_flakey
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
# real QA test starts here
_need_to_be_root
_supported_fs generic
_supported_os Linux
_require_scratch
_require_dm_flakey
_require_metadata_journaling $SCRATCH_DEV
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test directory and file.
mkdir $SCRATCH_MNT/testdir
touch $SCRATCH_MNT/foo
ln $SCRATCH_MNT/foo $SCRATCH_MNT/testdir/foo2
ln $SCRATCH_MNT/foo $SCRATCH_MNT/testdir/foo3
# Make sure everything done so far is durably persisted.
sync
# Now we remove one of our file's hardlinks in the directory testdir.
unlink $SCRATCH_MNT/testdir/foo3
# We now fsync our file using the "foo" link, which has a parent that
# is not the directory "testdir".
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Silently drop all writes and unmount to simulate a crash/power
# failure.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again, mount to trigger journal/log replay.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# After the journal/log is replayed we expect to not see the "foo3"
# link anymore and we should be able to remove all names in the
# directory "testdir" and then remove it (no stale directory entries
# left after the journal/log replay).
echo "Entries in testdir:"
ls -1 $SCRATCH_MNT/testdir
rm -f $SCRATCH_MNT/testdir/*
rmdir $SCRATCH_MNT/testdir
_unmount_flakey
status=0
exit
The test fails with:
$ ./check generic/107
FSTYP -- btrfs
PLATFORM -- Linux/x86_64 debian3 4.1.0-rc6-btrfs-next-11+
MKFS_OPTIONS -- /dev/sdc
MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1
generic/107 3s ... - output mismatch (see .../results/generic/107.out.bad)
--- tests/generic/107.out 2015-08-01 01:39:45.807462161 +0100
+++ /home/fdmanana/git/hub/xfstests/results//generic/107.out.bad
@@ -1,3 +1,5 @@
QA output created by 107
Entries in testdir:
foo2
+foo3
+rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/testdir': Directory not empty
...
_check_btrfs_filesystem: filesystem on /dev/sdc is inconsistent \
(see /home/fdmanana/git/hub/xfstests/results//generic/107.full)
_check_dmesg: something found in dmesg (see .../results/generic/107.dmesg)
Ran: generic/107
Failures: generic/107
Failed 1 of 1 tests
$ cat /home/fdmanana/git/hub/xfstests/results//generic/107.full
(...)
checking fs roots
root 5 inode 257 errors 200, dir isize wrong
unresolved ref dir 257 index 3 namelen 4 name foo3 filetype 1 errors 5, no dir item, no inode ref
(...)
And produces the following warning in dmesg:
[127298.759064] BTRFS info (device dm-0): failed to delete reference to foo3, inode 258 parent 257
[127298.762081] ------------[ cut here ]------------
[127298.763311] WARNING: CPU: 10 PID: 7891 at fs/btrfs/inode.c:3956 __btrfs_unlink_inode+0x182/0x35a [btrfs]()
[127298.767327] BTRFS: Transaction aborted (error -2)
(...)
[127298.788611] Call Trace:
[127298.789137] [<ffffffff8145f077>] dump_stack+0x4f/0x7b
[127298.790090] [<ffffffff81095de5>] ? console_unlock+0x356/0x3a2
[127298.791157] [<ffffffff8104b3b0>] warn_slowpath_common+0xa1/0xbb
[127298.792323] [<ffffffffa065ad09>] ? __btrfs_unlink_inode+0x182/0x35a [btrfs]
[127298.793633] [<ffffffff8104b410>] warn_slowpath_fmt+0x46/0x48
[127298.794699] [<ffffffffa065ad09>] __btrfs_unlink_inode+0x182/0x35a [btrfs]
[127298.797640] [<ffffffffa065be8f>] btrfs_unlink_inode+0x1e/0x40 [btrfs]
[127298.798876] [<ffffffffa065bf11>] btrfs_unlink+0x60/0x9b [btrfs]
[127298.800154] [<ffffffff8116fb48>] vfs_unlink+0x9c/0xed
[127298.801303] [<ffffffff81173481>] do_unlinkat+0x12b/0x1fb
[127298.802450] [<ffffffff81253855>] ? lockdep_sys_exit_thunk+0x12/0x14
[127298.803797] [<ffffffff81174056>] SyS_unlinkat+0x29/0x2b
[127298.805017] [<ffffffff81465197>] system_call_fastpath+0x12/0x6f
[127298.806310] ---[ end trace bbfddacb7aaada7b ]---
[127298.807325] BTRFS warning (device dm-0): __btrfs_unlink_inode:3956: Aborting unused transaction(No such entry).
So fix this by logging all parent inodes, current and old ones, to make
sure we do not get stale entries after log replay. This is not a simple
solution such as triggering a full transaction commit because it would
imply full transaction commit when an inode is fsynced in the same
transaction that modified it and reloaded it after eviction (because its
last_unlink_trans is set to the same value as its last_trans as of the
commit with the title "Btrfs: fix stale dir entries after unlink, inode
eviction and fsync"), and it would also make fstest generic/066 fail
since one of the fsyncs triggers a full commit and the next fsync will
not find the inode in the log anymore (therefore not removing the xattr).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The search key advancing condition used in copy_to_sk() is loose. It can
advance the key even if it reaches sk->max_*: e.g. when the max key = (512,
1024, -1) and the current key = (512, 1025, 10), it increments the
offset by 1, continues hopeless search from (512, 1025, 11). This issue
make ioctl() to take unexpectedly long time scanning all the leaf a blocks
one by one.
This commit fix the problem using standard way of key comparison:
btrfs_comp_cpu_keys()
Signed-off-by: Naohiro Aota <naota@elisp.net>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When cloning/deduplicating file extents (through the clone and extent_same
ioctls) we can get data back references with offset values that are a
result of an unsigned integer arithmetic underflow, that is, values that
are much larger then they could be otherwise.
This is not a problem when decrementing or dropping the back references
(happens when we overwrite the extents or punch a hole for example, through
__btrfs_drop_extents()), since we compute the same too large offset value,
but it is a problem for the backref walking code, used by an incremental
send and the ioctls that are used by the btrfs tool "inspect-internal"
commands, as it makes it miss the corresponding file extent items because
the search key is set for an extent item that starts at an offset matching
the exceptionally large offset value of the data back reference. For an
incremental send this causes the send ioctl to fail with -EIO.
So teach the backref walking code to deal with these cases by setting the
search key's offset to 0 if the backref's offset value is larger than
LLONG_MAX (the largest possible file offset). This makes sure the backref
walking code finds the corresponding file extent items at the expense of
scanning more items and leafs in the btree.
Fixing the clone/dedup ioctls to not produce such underflowed results would
require major changes breaking backward compatibility, updating user space
tools, etc.
Simple reproducer case for fstests:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
rm -fr $send_files_dir
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_cloner
_need_to_be_root
send_files_dir=$TEST_DIR/btrfs-test-$seq
rm -f $seqres.full
rm -fr $send_files_dir
mkdir $send_files_dir
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
# Create our test file with a single extent of 64K starting at file
# offset 128K.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 128K 64K" $SCRATCH_MNT/foo \
| _filter_xfs_io
_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \
$SCRATCH_MNT/mysnap1
# Now clone parts of the original extent into lower offsets of the file.
#
# The first clone operation adds a file extent item to file offset 0
# that points to our initial extent with a data offset of 16K. The
# corresponding data back reference in the extent tree has an offset of
# 18446744073709535232, which is the result of file_offset - data_offset
# = 0 - 16K.
#
# The second clone operation adds a file extent item to file offset 16K
# that points to our initial extent with a data offset of 48K. The
# corresponding data back reference in the extent tree has an offset of
# 18446744073709518848, which is the result of file_offset - data_offset
# = 16K - 48K.
#
# Those large back reference offsets (result of unsigned arithmetic
# underflow) confused the back reference walking code (used by an
# incremental send and the multiple inspect-internal ioctls) and made it
# miss the back references, which for the case of an incremental send it
# made it fail with -EIO and print a message like the following to
# dmesg:
#
# "BTRFS error (device sdc): did not find backref in send_root. \
# inode=257, offset=0, disk_byte=12845056 found extent=12845056"
#
$CLONER_PROG -s $(((128 + 16) * 1024)) -d 0 -l $((16 * 1024)) \
$SCRATCH_MNT/foo $SCRATCH_MNT/foo
$CLONER_PROG -s $(((128 + 48) * 1024)) -d $((16 * 1024)) \
-l $((16 * 1024)) $SCRATCH_MNT/foo $SCRATCH_MNT/foo
_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \
$SCRATCH_MNT/mysnap2
_run_btrfs_util_prog send $SCRATCH_MNT/mysnap1 -f $send_files_dir/1.snap
_run_btrfs_util_prog send -p $SCRATCH_MNT/mysnap1 $SCRATCH_MNT/mysnap2 \
-f $send_files_dir/2.snap
echo "File digest in the original filesystem:"
md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch
# Now recreate the filesystem by receiving both send streams and verify
# we get the same file contents that the original filesystem had.
_scratch_unmount
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/1.snap
_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/2.snap
echo "File digest in the new filesystem:"
md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch
status=0
exit
The test's expected golden output is:
wrote 65536/65536 bytes at offset 131072
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File digest in the original filesystem:
6c6079335cff141b8a31233ead04cbff SCRATCH_MNT/mysnap2/foo
File digest in the new filesystem:
6c6079335cff141b8a31233ead04cbff SCRATCH_MNT/mysnap2/foo
But it failed with:
(...)
@@ -1,7 +1,5 @@
QA output created by 097
wrote 65536/65536 bytes at offset 131072
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-File digest in the original filesystem:
-6c6079335cff141b8a31233ead04cbff SCRATCH_MNT/mysnap2/foo
-File digest in the new filesystem:
-6c6079335cff141b8a31233ead04cbff SCRATCH_MNT/mysnap2/foo
...
$ cat /home/fdmanana/git/hub/xfstests/results//btrfs/097.full
(...)
ERROR: send ioctl failed with -5: Input/output error
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we remove a hard link from an inode, the inode gets evicted, then
we fsync the inode and then power fail/crash, when the log tree is
replayed, the parent directory inode still has entries pointing to
the name that no longer exists, while our inode no longer has the
BTRFS_INODE_REF_KEY item matching the deleted hard link (as expected),
leaving the filesystem in an inconsistent state. The stale directory
entries can not be deleted (an attempt to delete them causes -ESTALE
errors), which makes it impossible to delete the parent directory.
This happens because we track the id of the transaction where the last
unlink operation for the inode happened (last_unlink_trans) in an
in-memory only field of the inode, that is, a value that is never
persisted in the inode item stored on the fs/subvol btree. So if an
inode is evicted and loaded again, the value for last_unlink_trans is
set to 0, which prevents the fsync from logging the parent directory
at btrfs_log_inode_parent(). So fix this by setting last_unlink_trans
to the id of the transaction that last modified the inode when we
load the inode. This is a pessimistic approach but it always ensures
correctness with the trade off of ocassional full transaction commits
when an fsync is done against the inode in the same transaction where
it was evicted and reloaded when our inode is a directory and often
logging its parent unnecessarily when our inode is not a directory.
The following test case for fstests triggers the problem:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
_cleanup_flakey
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
# real QA test starts here
_need_to_be_root
_supported_fs generic
_supported_os Linux
_require_scratch
_require_dm_flakey
_require_metadata_journaling $SCRATCH_DEV
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test file with 2 hard links.
mkdir $SCRATCH_MNT/testdir
touch $SCRATCH_MNT/testdir/foo
ln $SCRATCH_MNT/testdir/foo $SCRATCH_MNT/testdir/bar
# Make sure everything done so far is durably persisted.
sync
# Now remove one of the links, trigger inode eviction and then fsync
# our inode.
unlink $SCRATCH_MNT/testdir/bar
echo 2 > /proc/sys/vm/drop_caches
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/testdir/foo
# Silently drop all writes on our scratch device to simulate a power failure.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again and mount the fs to trigger log/journal replay.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Now verify our directory entries.
echo "Entries in testdir:"
ls -1 $SCRATCH_MNT/testdir
# If we remove our inode, its parent should become empty and therefore we should
# be able to remove the parent.
rm -f $SCRATCH_MNT/testdir/*
rmdir $SCRATCH_MNT/testdir
_unmount_flakey
# The fstests framework will call fsck against our filesystem which will verify
# that all metadata is in a consistent state.
status=0
exit
The test failed on btrfs with:
generic/098 4s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/098.out.bad)
--- tests/generic/098.out 2015-07-23 18:01:12.616175932 +0100
+++ /home/fdmanana/git/hub/xfstests/results//generic/098.out.bad 2015-07-23 18:04:58.924138308 +0100
@@ -1,3 +1,6 @@
QA output created by 098
Entries in testdir:
+bar
foo
+rm: cannot remove '/home/fdmanana/btrfs-tests/scratch_1/testdir/foo': Stale file handle
+rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/testdir': Directory not empty
...
(Run 'diff -u tests/generic/098.out /home/fdmanana/git/hub/xfstests/results//generic/098.out.bad' to see the entire diff)
_check_btrfs_filesystem: filesystem on /dev/sdc is inconsistent (see /home/fdmanana/git/hub/xfstests/results//generic/098.full)
$ cat /home/fdmanana/git/hub/xfstests/results//generic/098.full
(...)
checking fs roots
root 5 inode 258 errors 2001, no inode item, link count wrong
unresolved ref dir 257 index 0 namelen 3 name foo filetype 1 errors 6, no dir index, no inode ref
unresolved ref dir 257 index 3 namelen 3 name bar filetype 1 errors 5, no dir item, no inode ref
Checking filesystem on /dev/sdc
(...)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We have another case where after an fsync log replay we get an inode with
a wrong link count (smaller than it should be) and a number of directory
entries greater than its link count. This happens when we add a new link
hard link to our inode A and then we fsync some other inode B that has
the side effect of logging the parent directory inode too. In this case
at log replay time we add the new hard link to our inode (the item with
key BTRFS_INODE_REF_KEY) when processing the parent directory but we
never adjust the link count of our inode A. As a result we get stale dir
entries for our inode A that can never be deleted and therefore it makes
it impossible to remove the parent directory (as its i_size can never
decrease back to 0).
A simple reproducer for fstests that triggers this issue:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
_cleanup_flakey
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
# real QA test starts here
_need_to_be_root
_supported_fs generic
_supported_os Linux
_require_scratch
_require_dm_flakey
_require_metadata_journaling $SCRATCH_DEV
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test directory and files.
mkdir $SCRATCH_MNT/testdir
touch $SCRATCH_MNT/testdir/foo
touch $SCRATCH_MNT/testdir/bar
# Make sure everything done so far is durably persisted.
sync
# Create one hard link for file foo and another one for file bar. After
# that fsync only the file bar.
ln $SCRATCH_MNT/testdir/bar $SCRATCH_MNT/testdir/bar_link
ln $SCRATCH_MNT/testdir/foo $SCRATCH_MNT/testdir/foo_link
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/testdir/bar
# Silently drop all writes on scratch device to simulate power failure.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again and mount the fs to trigger log/journal replay.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Now verify both our files have a link count of 2.
echo "Link count for file foo: $(stat --format=%h $SCRATCH_MNT/testdir/foo)"
echo "Link count for file bar: $(stat --format=%h $SCRATCH_MNT/testdir/bar)"
# We should be able to remove all the links of our files in testdir, and
# after that the parent directory should become empty and therefore
# possible to remove it.
rm -f $SCRATCH_MNT/testdir/*
rmdir $SCRATCH_MNT/testdir
_unmount_flakey
# The fstests framework will call fsck against our filesystem which will verify
# that all metadata is in a consistent state.
status=0
exit
The test fails with:
-Link count for file foo: 2
+Link count for file foo: 1
Link count for file bar: 2
+rm: cannot remove '/home/fdmanana/btrfs-tests/scratch_1/testdir/foo_link': Stale file handle
+rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/testdir': Directory not empty
(...)
_check_btrfs_filesystem: filesystem on /dev/sdc is inconsistent
And fsck's output:
(...)
checking fs roots
root 5 inode 258 errors 2001, no inode item, link count wrong
unresolved ref dir 257 index 5 namelen 8 name foo_link filetype 1 errors 4, no inode ref
Checking filesystem on /dev/sdc
(...)
So fix this by marking inodes for link count fixup at log replay time
whenever a directory entry is replayed if the entry was created in the
transaction where the fsync was made and if it points to a non-directory
inode.
This isn't a new problem/regression, the issue exists for a long time,
possibly since the log tree feature was added (2008).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fix from Chris Mason:
"We have a btrfs quota regression fix.
I merged this one on Thursday and have run it through tests against
current master.
Normally I wouldn't have sent this while you were finalizing rc6, but
I'm feeding mosquitoes in the adirondacks next week, so I wanted to
get this one out before leaving. I'll leave longer tests running and
check on things during the week, but I don't expect any problems"
* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: qgroup: Fix a regression in qgroup reserved space.
During the change to new btrfs extent-oriented qgroup implement, due to
it doesn't use the old __qgroup_excl_accounting() for exclusive extent,
it didn't free the reserved bytes.
The bug will cause limit function go crazy as the reserved space is
never freed, increasing limit will have no effect and still cause
EQOUT.
The fix is easy, just free reserved bytes for newly created exclusive
extent as what it does before.
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Yang Dongsheng <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
With well over 200+ users of this api, there are a mere 12 users that
actually checked the return value of this function. And all of them
really didn't do anything with that information as the system or module
was shutting down no matter what.
So stop pretending like it matters, and just return void from
misc_deregister(). If something goes wrong in the call, you will get a
WARNING splat in the syslog so you know how to fix up your driver.
Other than that, there's nothing that can go wrong.
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Neil Brown <neilb@suse.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Christine Caulfield <ccaulfie@redhat.com>
Cc: David Teigland <teigland@redhat.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull btrfs fixes from Chris Mason:
"Filipe fixed up a hard to trigger ENOSPC regression from our merge
window pull, and we have a few other smaller fixes"
* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix quick exhaustion of the system array in the superblock
btrfs: its btrfs_err() instead of btrfs_error()
btrfs: Avoid NULL pointer dereference of free_extent_buffer when read_tree_block() fail
btrfs: Fix lockdep warning of btrfs_run_delayed_iputs()
When we clear the dirty bits in btrfs_delete_unused_bgs for extents
in the empty block group, it results in btrfs_finish_extent_commit being
unable to discard the freed extents.
The block group removal patch added an alternate path to forget extents
other than btrfs_finish_extent_commit. As a result, any extents that
would be freed when the block group is removed aren't discarded. In my
test run, with a large copy of mixed sized files followed by removal, it
left nearly 2/3 of extents undiscarded.
To clean up the block groups, we add the removed block group onto a list
that will be discarded after transaction commit.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The cleaner thread may already be sleeping by the time we enter
close_ctree. If that's the case, we'll skip removing any unused
block groups queued for removal, even during a normal umount.
They'll be cleaned up automatically at next mount, but users
expect a umount to be a clean synchronization point, especially
when used on thin-provisioned storage with -odiscard. We also
explicitly remove unused block groups in the ro-remount path
for the same reason.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Since we now clean up block groups automatically as they become
empty, iterating over block groups is no longer sufficient to discard
unused space.
This patch iterates over the unused chunk space and discards any regions
that are unallocated, regardless of whether they were ever used. This is
a change for btrfs but is consistent with other file systems.
We do this in a transactionless manner since the discard process can take
a substantial amount of time and a transaction would need to be started
before the acquisition of the device list lock. That would mean a
transaction would be held open across /all/ of the discards collectively.
In order to prevent other threads from allocating or freeing chunks, we
hold the chunks lock across the search and discard calls. We release it
between searches to allow the file system to perform more-or-less
normally. Since the running transaction can commit and disappear while
we're using the transaction pointer, we take a reference to it and
release it after the search. This is safe since it would happen normally
at the end of the transaction commit after any locks are released anyway.
We also take the commit_root_sem to protect against a transaction starting
and committing while we're running.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Btrfs doesn't track superblocks with extent records so there is nothing
persistent on-disk to indicate that those blocks are in use. We track
the superblocks in memory to ensure they don't get used by removing them
from the free space cache when we load a block group from disk. Prior
to 47ab2a6c6a (Btrfs: remove empty block groups automatically), that
was fine since the block group would never be reclaimed so the superblock
was always safe. Once we started removing the empty block groups, we
were protected by the fact that discards weren't being properly issued
for unused space either via FITRIM or -odiscard. The block groups were
still being released, but the blocks remained on disk.
In order to properly discard unused block groups, we need to filter out
the superblocks from the discard range. Superblocks are located at fixed
locations on each device, so it makes sense to filter them out in
btrfs_issue_discard, which is used by both -odiscard and FITRIM.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
It's possible, though unexpected, to pass unaligned offsets and lengths
to btrfs_issue_discard. We then shift the offset/length values to sector
units. If an unaligned offset has been passed, it will result in the
entire sector being discarded, possibly losing data. An unaligned
length is safe but we'll end up returning an inaccurate number of
discarded bytes.
This patch aligns the offset to the 512B boundary, adjusts the length,
and warns, since we shouldn't be discarding on an offset that isn't
aligned with our sector size.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Initially this will just be the length argument passed to it,
but the following patches will adjust that to reflect re-alignment
and skipped blocks.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently we have two different ways to signal an I/O error on a BIO:
(1) by clearing the BIO_UPTODATE flag
(2) by returning a Linux errno value to the bi_end_io callback
The first one has the drawback of only communicating a single possible
error (-EIO), and the second one has the drawback of not beeing persistent
when bios are queued up, and are not passed along from child to parent
bio in the ever more popular chaining scenario. Having both mechanisms
available has the additional drawback of utterly confusing driver authors
and introducing bugs where various I/O submitters only deal with one of
them, and the others have to add boilerplate code to deal with both kinds
of error returns.
So add a new bi_error field to store an errno value directly in struct
bio and remove the existing mechanisms to clean all this up.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Omar reported that after commit 4fbcdf6694 ("Btrfs: fix -ENOSPC when
finishing block group creation"), introduced in 4.2-rc1, the following
test was failing due to exhaustion of the system array in the superblock:
#!/bin/bash
truncate -s 100T big.img
mkfs.btrfs big.img
mount -o loop big.img /mnt/loop
num=5
sz=10T
for ((i = 0; i < $num; i++)); do
echo fallocate $i $sz
fallocate -l $sz /mnt/loop/testfile$i
done
btrfs filesystem sync /mnt/loop
for ((i = 0; i < $num; i++)); do
echo rm $i
rm /mnt/loop/testfile$i
btrfs filesystem sync /mnt/loop
done
umount /mnt/loop
This made btrfs_add_system_chunk() fail with -EFBIG due to excessive
allocation of system block groups. This happened because the test creates
a large number of data block groups per transaction and when committing
the transaction we start the writeout of the block group caches for all
the new new (dirty) block groups, which results in pre-allocating space
for each block group's free space cache using the same transaction handle.
That in turn often leads to creation of more block groups, and all get
attached to the new_bgs list of the same transaction handle to the point
of getting a list with over 1500 elements, and creation of new block groups
leads to the need of reserving space in the chunk block reserve and often
creating a new system block group too.
So that made us quickly exhaust the chunk block reserve/system space info,
because as of the commit mentioned before, we do reserve space for each
new block group in the chunk block reserve, unlike before where we would
not and would at most allocate one new system block group and therefore
would only ensure that there was enough space in the system space info to
allocate 1 new block group even if we ended up allocating thousands of
new block groups using the same transaction handle. That worked most of
the time because the computed required space at check_system_chunk() is
very pessimistic (assumes a chunk tree height of BTRFS_MAX_LEVEL/8 and
that all nodes/leafs in a path will be COWed and split) and since the
updates to the chunk tree all happen at btrfs_create_pending_block_groups
it is unlikely that a path needs to be COWed more than once (unless
writepages() for the btree inode is called by mm in between) and that
compensated for the need of creating any new nodes/leads in the chunk
tree.
So fix this by ensuring we don't accumulate a too large list of new block
groups in a transaction's handles new_bgs list, inserting/updating the
chunk tree for all accumulated new block groups and releasing the unused
space from the chunk block reserve whenever the list becomes sufficiently
large. This is a generic solution even though the problem currently can
only happen when starting the writeout of the free space caches for all
dirty block groups (btrfs_start_dirty_block_groups()).
Reported-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
sorry I indented to use btrfs_err() and I have no idea
how btrfs_error() got there.
infact I was thinking about these kind of oversights
since these two func are too closely named.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Liu Bo <bo.li.liu@oracle.com> reported a lockdep warning of
delayed_iput_sem in xfstests generic/241:
[ 2061.345955] =============================================
[ 2061.346027] [ INFO: possible recursive locking detected ]
[ 2061.346027] 4.1.0+ #268 Tainted: G W
[ 2061.346027] ---------------------------------------------
[ 2061.346027] btrfs-cleaner/3045 is trying to acquire lock:
[ 2061.346027] (&fs_info->delayed_iput_sem){++++..}, at:
[<ffffffff814063ab>] btrfs_run_delayed_iputs+0x6b/0x100
[ 2061.346027] but task is already holding lock:
[ 2061.346027] (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffff814063ab>] btrfs_run_delayed_iputs+0x6b/0x100
[ 2061.346027] other info that might help us debug this:
[ 2061.346027] Possible unsafe locking scenario:
[ 2061.346027] CPU0
[ 2061.346027] ----
[ 2061.346027] lock(&fs_info->delayed_iput_sem);
[ 2061.346027] lock(&fs_info->delayed_iput_sem);
[ 2061.346027]
*** DEADLOCK ***
It is rarely happened, about 1/400 in my test env.
The reason is recursion of btrfs_run_delayed_iputs():
cleaner_kthread
-> btrfs_run_delayed_iputs() *1
-> get delayed_iput_sem lock *2
-> iput()
-> ...
-> btrfs_commit_transaction()
-> btrfs_run_delayed_iputs() *1
-> get delayed_iput_sem lock (dead lock) *2
*1: recursion of btrfs_run_delayed_iputs()
*2: warning of lockdep about delayed_iput_sem
When fs is in high stress, new iputs may added into fs_info->delayed_iputs
list when btrfs_run_delayed_iputs() is running, which cause
second btrfs_run_delayed_iputs() run into down_read(&fs_info->delayed_iput_sem)
again, and cause above lockdep warning.
Actually, it will not cause real problem because both locks are read lock,
but to avoid lockdep warning, we can do a fix.
Fix:
Don't do btrfs_run_delayed_iputs() in btrfs_commit_transaction() for
cleaner_kthread thread to break above recursion path.
cleaner_kthread is calling btrfs_run_delayed_iputs() explicitly in code,
and don't need to call btrfs_run_delayed_iputs() again in
btrfs_commit_transaction(), it also give us a bonus to avoid stack overflow.
Test:
No above lockdep warning after patch in 1200 generic/241 tests.
Reported-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"These are all from Filipe, and cover a few problems we've had reported
on the list recently (along with ones he found on his own)"
* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix file corruption after cloning inline extents
Btrfs: fix order by which delayed references are run
Btrfs: fix list transaction->pending_ordered corruption
Btrfs: fix memory leak in the extent_same ioctl
Btrfs: fix shrinking truncate when the no_holes feature is enabled
Using the clone ioctl (or extent_same ioctl, which calls the same extent
cloning function as well) we end up allowing copy an inline extent from
the source file into a non-zero offset of the destination file. This is
something not expected and that the btrfs code is not prepared to deal
with - all inline extents must be at a file offset equals to 0.
For example, the following excerpt of a test case for fstests triggers
a crash/BUG_ON() on a write operation after an inline extent is cloned
into a non-zero offset:
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
# Create our test files. File foo has the same 2K of data at offset 4K
# as file bar has at its offset 0.
$XFS_IO_PROG -f -s -c "pwrite -S 0xaa 0 4K" \
-c "pwrite -S 0xbb 4k 2K" \
-c "pwrite -S 0xcc 8K 4K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# File bar consists of a single inline extent (2K size).
$XFS_IO_PROG -f -s -c "pwrite -S 0xbb 0 2K" \
$SCRATCH_MNT/bar | _filter_xfs_io
# Now call the clone ioctl to clone the extent of file bar into file
# foo at its offset 4K. This made file foo have an inline extent at
# offset 4K, something which the btrfs code can not deal with in future
# IO operations because all inline extents are supposed to start at an
# offset of 0, resulting in all sorts of chaos.
# So here we validate that clone ioctl returns an EOPNOTSUPP, which is
# what it returns for other cases dealing with inlined extents.
$CLONER_PROG -s 0 -d $((4 * 1024)) -l $((2 * 1024)) \
$SCRATCH_MNT/bar $SCRATCH_MNT/foo
# Because of the inline extent at offset 4K, the following write made
# the kernel crash with a BUG_ON().
$XFS_IO_PROG -c "pwrite -S 0xdd 6K 2K" $SCRATCH_MNT/foo | _filter_xfs_io
status=0
exit
The stack trace of the BUG_ON() triggered by the last write is:
[152154.035903] ------------[ cut here ]------------
[152154.036424] kernel BUG at mm/page-writeback.c:2286!
[152154.036424] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[152154.036424] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc acpi_cpu$
[152154.036424] CPU: 2 PID: 17873 Comm: xfs_io Tainted: G W 4.1.0-rc6-btrfs-next-11+ #2
[152154.036424] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
[152154.036424] task: ffff880429f70990 ti: ffff880429efc000 task.ti: ffff880429efc000
[152154.036424] RIP: 0010:[<ffffffff8111a9d5>] [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
[152154.036424] RSP: 0018:ffff880429effc68 EFLAGS: 00010246
[152154.036424] RAX: 0200000000000806 RBX: ffffea0006a6d8f0 RCX: 0000000000000001
[152154.036424] RDX: 0000000000000000 RSI: ffffffff81155d1b RDI: ffffea0006a6d8f0
[152154.036424] RBP: ffff880429effc78 R08: ffff8801ce389fe0 R09: 0000000000000001
[152154.036424] R10: 0000000000002000 R11: ffffffffffffffff R12: ffff8800200dce68
[152154.036424] R13: 0000000000000000 R14: ffff8800200dcc88 R15: ffff8803d5736d80
[152154.036424] FS: 00007fbf119f6700(0000) GS:ffff88043d280000(0000) knlGS:0000000000000000
[152154.036424] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[152154.036424] CR2: 0000000001bdc000 CR3: 00000003aa555000 CR4: 00000000000006e0
[152154.036424] Stack:
[152154.036424] ffff8803d5736d80 0000000000000001 ffff880429effcd8 ffffffffa04e97c1
[152154.036424] ffff880429effd68 ffff880429effd60 0000000000000001 ffff8800200dc9c8
[152154.036424] 0000000000000001 ffff8800200dcc88 0000000000000000 0000000000001000
[152154.036424] Call Trace:
[152154.036424] [<ffffffffa04e97c1>] lock_and_cleanup_extent_if_need+0x147/0x18d [btrfs]
[152154.036424] [<ffffffffa04ea82c>] __btrfs_buffered_write+0x245/0x4c8 [btrfs]
[152154.036424] [<ffffffffa04ed14b>] ? btrfs_file_write_iter+0x150/0x3e0 [btrfs]
[152154.036424] [<ffffffffa04ed15a>] ? btrfs_file_write_iter+0x15f/0x3e0 [btrfs]
[152154.036424] [<ffffffffa04ed2c7>] btrfs_file_write_iter+0x2cc/0x3e0 [btrfs]
[152154.036424] [<ffffffff81165a4a>] __vfs_write+0x7c/0xa5
[152154.036424] [<ffffffff81165f89>] vfs_write+0xa0/0xe4
[152154.036424] [<ffffffff81166855>] SyS_pwrite64+0x64/0x82
[152154.036424] [<ffffffff81465197>] system_call_fastpath+0x12/0x6f
[152154.036424] Code: 48 89 c7 e8 0f ff ff ff 5b 41 5c 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb e8 ae ef 00 00 49 89 c4 48 8b 03 a8 01 75 02 <0f> 0b 4d 85 e4 74 59 49 8b 3c 2$
[152154.036424] RIP [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
[152154.036424] RSP <ffff880429effc68>
[152154.242621] ---[ end trace e3d3376b23a57041 ]---
Fix this by returning the error EOPNOTSUPP if an attempt to copy an
inline extent into a non-zero offset happens, just like what is done for
other scenarios that would require copying/splitting inline extents,
which were introduced by the following commits:
00fdf13a2e ("Btrfs: fix a crash of clone with inline extents's split")
3f9e3df8da ("btrfs: replace error code from btrfs_drop_extents")
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
When we have an extent that got N references removed and N new references
added in the same transaction, we must run the insertion of the references
first because otherwise the last removed reference will remove the extent
item from the extent tree, resulting in a failure for the insertions.
This is a regression introduced in the 4.2-rc1 release and this fix just
brings back the behaviour of selecting reference additions before any
reference removals.
The following test case for fstests reproduces the issue:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
tmp=/tmp/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
_cleanup_flakey
rm -f $tmp.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
# real QA test starts here
_need_to_be_root
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_dm_flakey
_require_cloner
_require_metadata_journaling $SCRATCH_DEV
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_init_flakey
_mount_flakey
# Create prealloc extent covering range [160K, 620K[
$XFS_IO_PROG -f -c "falloc 160K 460K" $SCRATCH_MNT/foo
# Now write to the last 80K of the prealloc extent plus 40K to the unallocated
# space that immediately follows it. This creates a new extent of 40K that spans
# the range [620K, 660K[.
$XFS_IO_PROG -c "pwrite -S 0xaa 540K 120K" $SCRATCH_MNT/foo | _filter_xfs_io
# At this point, there are now 2 back references to the prealloc extent in our
# extent tree. Both are for our file offset 160K and one relates to a file
# extent item with a data offset of 0 and a length of 380K, while the other
# relates to a file extent item with a data offset of 380K and a length of 80K.
# Make sure everything done so far is durably persisted (all back references are
# in the extent tree, etc).
sync
# Now clone all extents of our file that cover the offset 160K up to its eof
# (660K at this point) into itself at offset 2M. This leaves a hole in the file
# covering the range [660K, 2M[. The prealloc extent will now be referenced by
# the file twice, once for offset 160K and once for offset 2M. The 40K extent
# that follows the prealloc extent will also be referenced twice by our file,
# once for offset 620K and once for offset 2M + 460K.
$CLONER_PROG -s $((160 * 1024)) -d $((2 * 1024 * 1024)) -l 0 $SCRATCH_MNT/foo \
$SCRATCH_MNT/foo
# Now create one new extent in our file with a size of 100Kb. It will span the
# range [3M, 3M + 100K[. It also will cause creation of a hole spanning the
# range [2M + 460K, 3M[. Our new file size is 3M + 100K.
$XFS_IO_PROG -c "pwrite -S 0xbb 3M 100K" $SCRATCH_MNT/foo | _filter_xfs_io
# At this point, there are now (in memory) 4 back references to the prealloc
# extent.
#
# Two of them are for file offset 160K, related to file extent items
# matching the file offsets 160K and 540K respectively, with data offsets of
# 0 and 380K respectively, and with lengths of 380K and 80K respectively.
#
# The other two references are for file offset 2M, related to file extent items
# matching the file offsets 2M and 2M + 380K respectively, with data offsets of
# 0 and 380K respectively, and with lengths of 389K and 80K respectively.
#
# The 40K extent has 2 back references, one for file offset 620K and the other
# for file offset 2M + 460K.
#
# The 100K extent has a single back reference and it relates to file offset 3M.
# Now clone our 100K extent into offset 600K. That offset covers the last 20K
# of the prealloc extent, the whole 40K extent and 40K of the hole starting at
# offset 660K.
$CLONER_PROG -s $((3 * 1024 * 1024)) -d $((600 * 1024)) -l $((100 * 1024)) \
$SCRATCH_MNT/foo $SCRATCH_MNT/foo
# At this point there's only one reference to the 40K extent, at file offset
# 2M + 460K, we have 4 references for the prealloc extent (2 for file offset
# 160K and 2 for file offset 2M) and 2 references for the 100K extent (1 for
# file offset 3M and a new one for file offset 600K).
# Now fsync our file to make all its new data and metadata updates are durably
# persisted and present if a power failure/crash happens after a successful
# fsync and before the next transaction commit.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
echo "File digest before power failure:"
md5sum $SCRATCH_MNT/foo | _filter_scratch
# Silently drop all writes and ummount to simulate a crash/power failure.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again, mount to trigger log replay and validate file contents.
# During log replay, the btrfs delayed references implementation used to run the
# deletion of back references before the addition of new back references, which
# made the addition fail as it didn't find the key in the extent tree that it
# was looking for. The failure triggered by this test was related to the 40K
# extent, which got 1 reference dropped and 1 reference added during the fsync
# log replay - when running the delayed references at transaction commit time,
# btrfs was applying the deletion before the insertion, resulting in a failure
# of the insertion that ended up turning the fs into read-only mode.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
echo "File digest after log replay:"
md5sum $SCRATCH_MNT/foo | _filter_scratch
_unmount_flakey
status=0
exit
This issue turned the filesystem into read-only mode (current transaction
aborted) and produced the following traces:
[ 8247.578385] ------------[ cut here ]------------
[ 8247.579947] WARNING: CPU: 0 PID: 11341 at fs/btrfs/extent-tree.c:1547 lookup_inline_extent_backref+0x17d/0x45d [btrfs]()
(...)
[ 8247.601697] Call Trace:
[ 8247.602222] [<ffffffff8145f077>] dump_stack+0x4f/0x7b
[ 8247.604320] [<ffffffff8104b3b0>] warn_slowpath_common+0xa1/0xbb
[ 8247.605488] [<ffffffffa0506c8d>] ? lookup_inline_extent_backref+0x17d/0x45d [btrfs]
[ 8247.608226] [<ffffffffa0506c8d>] lookup_inline_extent_backref+0x17d/0x45d [btrfs]
[ 8247.617061] [<ffffffffa0507957>] insert_inline_extent_backref+0x41/0xb2 [btrfs]
[ 8247.621856] [<ffffffffa0507c4f>] __btrfs_inc_extent_ref+0x8c/0x20a [btrfs]
[ 8247.624366] [<ffffffffa050ee60>] __btrfs_run_delayed_refs+0xb0c/0xd49 [btrfs]
[ 8247.626176] [<ffffffffa0510dcd>] btrfs_run_delayed_refs+0x6d/0x1d4 [btrfs]
[ 8247.627435] [<ffffffff81155c9b>] ? __cache_free+0x4a7/0x4b6
[ 8247.628531] [<ffffffffa0520482>] btrfs_commit_transaction+0x4c/0xa20 [btrfs]
(...)
[ 8247.648430] ---[ end trace 2461e55f92c2ac2d ]---
[ 8247.727263] WARNING: CPU: 3 PID: 11341 at fs/btrfs/extent-tree.c:2771 btrfs_run_delayed_refs+0xa4/0x1d4 [btrfs]()
[ 8247.728954] BTRFS: Transaction aborted (error -5)
(...)
[ 8247.760866] Call Trace:
[ 8247.761534] [<ffffffff8145f077>] dump_stack+0x4f/0x7b
[ 8247.764271] [<ffffffff8104b3b0>] warn_slowpath_common+0xa1/0xbb
[ 8247.767582] [<ffffffffa0510e04>] ? btrfs_run_delayed_refs+0xa4/0x1d4 [btrfs]
[ 8247.769373] [<ffffffff8104b410>] warn_slowpath_fmt+0x46/0x48
[ 8247.770836] [<ffffffffa0510e04>] btrfs_run_delayed_refs+0xa4/0x1d4 [btrfs]
[ 8247.772532] [<ffffffff81155c9b>] ? __cache_free+0x4a7/0x4b6
[ 8247.773664] [<ffffffffa0520482>] btrfs_commit_transaction+0x4c/0xa20 [btrfs]
[ 8247.775047] [<ffffffff81087310>] ? trace_hardirqs_on+0xd/0xf
[ 8247.776176] [<ffffffff81155dd5>] ? kmem_cache_free+0x12b/0x189
[ 8247.777427] [<ffffffffa055a920>] btrfs_recover_log_trees+0x2da/0x33d [btrfs]
[ 8247.778575] [<ffffffffa055898e>] ? replay_one_extent+0x4fc/0x4fc [btrfs]
[ 8247.779838] [<ffffffffa051e265>] open_ctree+0x1cc0/0x201a [btrfs]
[ 8247.781020] [<ffffffff81120f48>] ? register_shrinker+0x56/0x81
[ 8247.782285] [<ffffffffa04fb12c>] btrfs_mount+0x5f0/0x734 [btrfs]
(...)
[ 8247.793394] ---[ end trace 2461e55f92c2ac2e ]---
[ 8247.794276] BTRFS: error (device dm-0) in btrfs_run_delayed_refs:2771: errno=-5 IO failure
[ 8247.797335] BTRFS: error (device dm-0) in btrfs_replay_log:2375: errno=-5 IO failure (Failed to recover log tree)
Fixes: c6fc245499 ("btrfs: delayed-ref: Use list to replace the ref_root in ref_head.")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Acked-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
When we call btrfs_commit_transaction(), we splice the list "ordered"
of our transaction handle into the transaction's "pending_ordered"
list, but we don't re-initialize the "ordered" list of our transaction
handle, this means it still points to the same elements it used to
before the splice. Then we check if the current transaction's state is
>= TRANS_STATE_COMMIT_START and if it is we end up calling
btrfs_end_transaction() which simply splices again the "ordered" list
of our handle into the transaction's "pending_ordered" list, leaving
multiple pointers to the same ordered extents which results in list
corruption when we are iterating, removing and freeing ordered extents
at btrfs_wait_pending_ordered(), resulting in access to dangling
pointers / use-after-free issues.
Similarly, btrfs_end_transaction() can end up in some cases calling
btrfs_commit_transaction(), and both did a list splice of the transaction
handle's "ordered" list into the transaction's "pending_ordered" without
re-initializing the handle's "ordered" list, resulting in exactly the
same problem.
This produces the following warning on a kernel with linked list
debugging enabled:
[109749.265416] ------------[ cut here ]------------
[109749.266410] WARNING: CPU: 7 PID: 324 at lib/list_debug.c:59 __list_del_entry+0x5a/0x98()
[109749.267969] list_del corruption. prev->next should be ffff8800ba087e20, but was fffffff8c1f7c35d
(...)
[109749.287505] Call Trace:
[109749.288135] [<ffffffff8145f077>] dump_stack+0x4f/0x7b
[109749.298080] [<ffffffff81095de5>] ? console_unlock+0x356/0x3a2
[109749.331605] [<ffffffff8104b3b0>] warn_slowpath_common+0xa1/0xbb
[109749.334849] [<ffffffff81260642>] ? __list_del_entry+0x5a/0x98
[109749.337093] [<ffffffff8104b410>] warn_slowpath_fmt+0x46/0x48
[109749.337847] [<ffffffff81260642>] __list_del_entry+0x5a/0x98
[109749.338678] [<ffffffffa053e8bf>] btrfs_wait_pending_ordered+0x46/0xdb [btrfs]
[109749.340145] [<ffffffffa058a65f>] ? __btrfs_run_delayed_items+0x149/0x163 [btrfs]
[109749.348313] [<ffffffffa054077d>] btrfs_commit_transaction+0x36b/0xa10 [btrfs]
[109749.349745] [<ffffffff81087310>] ? trace_hardirqs_on+0xd/0xf
[109749.350819] [<ffffffffa055370d>] btrfs_sync_file+0x36f/0x3fc [btrfs]
[109749.351976] [<ffffffff8118ec98>] vfs_fsync_range+0x8f/0x9e
[109749.360341] [<ffffffff8118ecc3>] vfs_fsync+0x1c/0x1e
[109749.368828] [<ffffffff8118ee1d>] do_fsync+0x34/0x4e
[109749.369790] [<ffffffff8118f045>] SyS_fsync+0x10/0x14
[109749.370925] [<ffffffff81465197>] system_call_fastpath+0x12/0x6f
[109749.382274] ---[ end trace 48e0d07f7c03d95a ]---
On a non-debug kernel this leads to invalid memory accesses, causing a
crash. Fix this by using list_splice_init() instead of list_splice() in
btrfs_commit_transaction() and btrfs_end_transaction().
Cc: stable@vger.kernel.org
Fixes: 50d9aa99bd ("Btrfs: make sure logged extents complete in the current transaction V3"
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
We were allocating memory with memdup_user() but we were never releasing
that memory. This affected pretty much every call to the ioctl, whether
it deduplicated extents or not.
This issue was reported on IRC by Julian Taylor and on the mailing list
by Marcel Ritter, credit goes to them for finding the issue.
Reported-by: Julian Taylor <jtaylor.debian@googlemail.com>
Reported-by: Marcel Ritter <ritter.marcel@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
If the no_holes feature is enabled, we attempt to shrink a file to a size
that ends up in the middle of a hole and we don't have any file extent
items in the fs/subvol tree that go beyond the new file size (or any
ordered extents that will insert such file extent items), we end up not
updating the inode's disk_i_size, we only update the inode's i_size.
This means that after unmounting and mounting the filesystem, or after
the inode is evicted and reloaded, its i_size ends up being incorrect
(an inode's i_size is set to the disk_i_size field when an inode is
loaded). This happens when btrfs_truncate_inode_items() doesn't find
any file extent items to drop - in this case it never makes a call to
btrfs_ordered_update_i_size() in order to update the inode's disk_i_size.
Example reproducer:
$ mkfs.btrfs -O no-holes -f /dev/sdd
$ mount /dev/sdd /mnt
# Create our test file with some data and durably persist it.
$ xfs_io -f -c "pwrite -S 0xaa 0 128K" /mnt/foo
$ sync
# Append some data to the file, increasing its size, and leave a hole
# between the old size and the start offset if the following write. So
# our file gets a hole in the range [128Kb, 256Kb[.
$ xfs_io -c "truncate 160K" /mnt/foo
# We expect to see our file with a size of 160Kb, with the first 128Kb
# of data all having the value 0xaa and the remaining 32Kb of data all
# having the value 0x00.
$ od -t x1 /mnt/foo
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0400000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0500000
# Now cleanly unmount and mount again the filesystem.
$ umount /mnt
$ mount /dev/sdd /mnt
# We expect to get the same result as before, a file with a size of
# 160Kb, with the first 128Kb of data all having the value 0xaa and the
# remaining 32Kb of data all having the value 0x00.
$ od -t x1 /mnt/foo
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0400000
In the example above the file size/data do not match what they were before
the remount.
Fix this by always calling btrfs_ordered_update_i_size() with a size
matching the size the file was truncated to if btrfs_truncate_inode_items()
is not called for a log tree and no file extent items were dropped. This
ensures the same behaviour as when the no_holes feature is not enabled.
A test case for fstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Pull btrfs fixes from Chris Mason:
"This is an assortment of fixes. Most of the commits are from Filipe
(fsync, the inode allocation cache and a few others). Mark kicked in
a series fixing corners in the extent sharing ioctls, and everyone
else fixed up on assorted other problems"
* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix wrong check for btrfs_force_chunk_alloc()
Btrfs: fix warning of bytes_may_use
Btrfs: fix hang when failing to submit bio of directIO
Btrfs: fix a comment in inode.c:evict_inode_truncate_pages()
Btrfs: fix memory corruption on failure to submit bio for direct IO
btrfs: don't update mtime/ctime on deduped inodes
btrfs: allow dedupe of same inode
btrfs: fix deadlock with extent-same and readpage
btrfs: pass unaligned length to btrfs_cmp_data()
Btrfs: fix fsync after truncate when no_holes feature is enabled
Btrfs: fix fsync xattr loss in the fast fsync path
Btrfs: fix fsync data loss after append write
Btrfs: fix crash on close_ctree() if cleaner starts new transaction
Btrfs: fix race between caching kthread and returning inode to inode cache
Btrfs: use kmem_cache_free when freeing entry in inode cache
Btrfs: fix race between balance and unused block group deletion
btrfs: add error handling for scrub_workers_get()
btrfs: cleanup noused initialization of dev in btrfs_end_bio()
btrfs: qgroup: allow user to clear the limitation on qgroup
Pull more vfs updates from Al Viro:
"Assorted VFS fixes and related cleanups (IMO the most interesting in
that part are f_path-related things and Eric's descriptor-related
stuff). UFS regression fixes (it got broken last cycle). 9P fixes.
fs-cache series, DAX patches, Jan's file_remove_suid() work"
[ I'd say this is much more than "fixes and related cleanups". The
file_table locking rule change by Eric Dumazet is a rather big and
fundamental update even if the patch isn't huge. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
9p: cope with bogus responses from server in p9_client_{read,write}
p9_client_write(): avoid double p9_free_req()
9p: forgetting to cancel request on interrupted zero-copy RPC
dax: bdev_direct_access() may sleep
block: Add support for DAX reads/writes to block devices
dax: Use copy_from_iter_nocache
dax: Add block size note to documentation
fs/file.c: __fget() and dup2() atomicity rules
fs/file.c: don't acquire files->file_lock in fd_install()
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
vfs: avoid creation of inode number 0 in get_next_ino
namei: make set_root_rcu() return void
make simple_positive() public
ufs: use dir_pages instead of ufs_dir_pages()
pagemap.h: move dir_pages() over there
remove the pointless include of lglock.h
fs: cleanup slight list_entry abuse
xfs: Correctly lock inode when removing suid and file capabilities
fs: Call security_ops->inode_killpriv on truncate
fs: Provide function telling whether file_remove_privs() will do anything
...
btrfs_force_chunk_alloc() return 1 for allocation chunk successfully.
This problem exists since commit c87f08ca4.
With this patch, we might fix some enospc problems for balances.
Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
While running generic/019, dmesg got several warnings from
btrfs_free_reserved_data_space().
Test generic/019 produces some disk failures so sumbit dio will get errors,
in which case, btrfs_direct_IO() goes to the error handling and free
bytes_may_use, but the problem is that bytes_may_use has been free'd
during get_block().
This adds a runtime flag to show if we've gone through get_block(), if so,
don't do the cleanup work.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The hang is uncoverd by generic/019.
btrfs_endio_direct_write() skips the "finish_ordered_fn" part when it hits
an error, thus those added ordered extents will never get processed, which
block processes that waiting for them via btrfs_start_ordered_extent().
This fixes the above, and meanwhile finish_ordered_fn will do the space
accounting work.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The comment was not correct about the part where it says the endio
callback of the bio might have not yet been called - update it
to mention that by that time the endio callback execution might
still be in progress only.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we fail to submit a bio for a direct IO request, we were grabbing the
corresponding ordered extent and decrementing its reference count twice,
once for our lookup reference and once for the ordered tree reference.
This was a problem because it caused the ordered extent to be freed
without removing it from the ordered tree and any lists it might be
attached to, leaving dangling pointers to the ordered extent around.
Example trace with CONFIG_DEBUG_PAGEALLOC=y:
[161779.858707] BUG: unable to handle kernel paging request at 0000000087654330
[161779.859983] IP: [<ffffffff8124ca68>] rb_prev+0x22/0x3b
[161779.860636] PGD 34d818067 PUD 0
[161779.860636] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
(...)
[161779.860636] Call Trace:
[161779.860636] [<ffffffffa06b36a6>] __tree_search+0xd9/0xf9 [btrfs]
[161779.860636] [<ffffffffa06b3708>] tree_search+0x42/0x63 [btrfs]
[161779.860636] [<ffffffffa06b4868>] ? btrfs_lookup_ordered_range+0x2d/0xa5 [btrfs]
[161779.860636] [<ffffffffa06b4873>] btrfs_lookup_ordered_range+0x38/0xa5 [btrfs]
[161779.860636] [<ffffffffa06aab8e>] btrfs_get_blocks_direct+0x11b/0x615 [btrfs]
[161779.860636] [<ffffffff8119727f>] do_blockdev_direct_IO+0x5ff/0xb43
[161779.860636] [<ffffffffa06aaa73>] ? btrfs_page_exists_in_range+0x1ad/0x1ad [btrfs]
[161779.860636] [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636] [<ffffffff811977f5>] __blockdev_direct_IO+0x32/0x34
[161779.860636] [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636] [<ffffffffa06a10ae>] btrfs_direct_IO+0x198/0x21f [btrfs]
[161779.860636] [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636] [<ffffffff81112ca1>] generic_file_direct_write+0xb3/0x128
[161779.860636] [<ffffffffa06affaa>] ? btrfs_file_write_iter+0x15f/0x3e0 [btrfs]
[161779.860636] [<ffffffffa06b004c>] btrfs_file_write_iter+0x201/0x3e0 [btrfs]
(...)
We were also not freeing the btrfs_dio_private we allocated previously,
which kmemleak reported with the following trace in its sysfs file:
unreferenced object 0xffff8803f553bf80 (size 96):
comm "xfs_io", pid 4501, jiffies 4295039588 (age 173.936s)
hex dump (first 32 bytes):
88 6c 9b f5 02 88 ff ff 00 00 00 00 00 00 00 00 .l..............
00 00 00 00 00 00 00 00 00 00 c4 00 00 00 00 00 ................
backtrace:
[<ffffffff81161ffe>] create_object+0x172/0x29a
[<ffffffff8145870f>] kmemleak_alloc+0x25/0x41
[<ffffffff81154e64>] kmemleak_alloc_recursive.constprop.40+0x16/0x18
[<ffffffff811579ed>] kmem_cache_alloc_trace+0xfb/0x148
[<ffffffffa03d8cff>] btrfs_submit_direct+0x65/0x16a [btrfs]
[<ffffffff811968dc>] dio_bio_submit+0x62/0x8f
[<ffffffff811975fe>] do_blockdev_direct_IO+0x97e/0xb43
[<ffffffff811977f5>] __blockdev_direct_IO+0x32/0x34
[<ffffffffa03d70ae>] btrfs_direct_IO+0x198/0x21f [btrfs]
[<ffffffff81112ca1>] generic_file_direct_write+0xb3/0x128
[<ffffffffa03e604d>] btrfs_file_write_iter+0x201/0x3e0 [btrfs]
[<ffffffff8116586a>] __vfs_write+0x7c/0xa5
[<ffffffff81165da9>] vfs_write+0xa0/0xe4
[<ffffffff81166675>] SyS_pwrite64+0x64/0x82
[<ffffffff81464fd7>] system_call_fastpath+0x12/0x6f
[<ffffffffffffffff>] 0xffffffffffffffff
For read requests we weren't doing any cleanup either (none of the work
done by btrfs_endio_direct_read()), so a failure submitting a bio for a
read request would leave a range in the inode's io_tree locked forever,
blocking any future operations (both reads and writes) against that range.
So fix this by making sure we do the same cleanup that we do for the case
where the bio submission succeeds.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
One issue users have reported is that dedupe changes mtime on files,
resulting in tools like rsync thinking that their contents have changed when
in fact the data is exactly the same. We also skip the ctime update as no
user-visible metadata changes here and we want dedupe to be transparent to
the user.
Clone still wants time changes, so we special case this in the code.
This was tested with the btrfs-extent-same tool.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
clone() supports cloning within an inode so extent-same can do
the same now. This patch fixes up the locking in extent-same to
know about the single-inode case. In addition to that, we add a
check for overlapping ranges, which clone does not allow.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
->readpage() does page_lock() before extent_lock(), we do the opposite in
extent-same. We want to reverse the order in btrfs_extent_same() but it's
not quite straightforward since the page locks are taken inside btrfs_cmp_data().
So I split btrfs_cmp_data() into 3 parts with a small context structure that
is passed between them. The first, btrfs_cmp_data_prepare() gathers up the
pages needed (taking page lock as required) and puts them on our context
structure. At this point, we are safe to lock the extent range. Afterwards,
we use btrfs_cmp_data() to do the data compare as usual and btrfs_cmp_data_free()
to clean up our context.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
In the case that we dedupe the tail of a file, we might expand the dedupe
len out to the end of our last block. We don't want to compare data past
i_size however, so pass the original length to btrfs_cmp_data().
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
When we have the no_holes feature enabled, if a we truncate a file to a
smaller size, truncate it again but to a size greater than or equals to
its original size and fsync it, the log tree will not have any information
about the hole covering the range [truncate_1_offset, new_file_size[.
Which means if the fsync log is replayed, the file will remain with the
state it had before both truncate operations.
Without the no_holes feature this does not happen, since when the inode
is logged (full sync flag is set) it will find in the fs/subvol tree a
leaf with a generation matching the current transaction id that has an
explicit extent item representing the hole.
Fix this by adding an explicit extent item representing a hole between
the last extent and the inode's i_size if we are doing a full sync.
The issue is easy to reproduce with the following test case for fstests:
. ./common/rc
. ./common/filter
. ./common/dmflakey
_need_to_be_root
_supported_fs generic
_supported_os Linux
_require_scratch
_require_dm_flakey
# This test was motivated by an issue found in btrfs when the btrfs
# no-holes feature is enabled (introduced in kernel 3.14). So enable
# the feature if the fs being tested is btrfs.
if [ $FSTYP == "btrfs" ]; then
_require_btrfs_fs_feature "no_holes"
_require_btrfs_mkfs_feature "no-holes"
MKFS_OPTIONS="$MKFS_OPTIONS -O no-holes"
fi
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test files and make sure everything is durably persisted.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 64K" \
-c "pwrite -S 0xbb 64K 61K" \
$SCRATCH_MNT/foo | _filter_xfs_io
$XFS_IO_PROG -f -c "pwrite -S 0xee 0 64K" \
-c "pwrite -S 0xff 64K 61K" \
$SCRATCH_MNT/bar | _filter_xfs_io
sync
# Now truncate our file foo to a smaller size (64Kb) and then truncate
# it to the size it had before the shrinking truncate (125Kb). Then
# fsync our file. If a power failure happens after the fsync, we expect
# our file to have a size of 125Kb, with the first 64Kb of data having
# the value 0xaa and the second 61Kb of data having the value 0x00.
$XFS_IO_PROG -c "truncate 64K" \
-c "truncate 125K" \
-c "fsync" \
$SCRATCH_MNT/foo
# Do something similar to our file bar, but the first truncation sets
# the file size to 0 and the second truncation expands the size to the
# double of what it was initially.
$XFS_IO_PROG -c "truncate 0" \
-c "truncate 253K" \
-c "fsync" \
$SCRATCH_MNT/bar
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again, mount to trigger log replay and validate file
# contents.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# We expect foo to have a size of 125Kb, the first 64Kb of data all
# having the value 0xaa and the remaining 61Kb to be a hole (all bytes
# with value 0x00).
echo "File foo content after log replay:"
od -t x1 $SCRATCH_MNT/foo
# We expect bar to have a size of 253Kb and no extents (any byte read
# from bar has the value 0x00).
echo "File bar content after log replay:"
od -t x1 $SCRATCH_MNT/bar
status=0
exit
The expected file contents in the golden output are:
File foo content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0200000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0372000
File bar content after log replay:
0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0772000
Without this fix, their contents are:
File foo content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0200000 bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
*
0372000
File bar content after log replay:
0000000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
*
0200000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0372000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0772000
A test case submission for fstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs updates from Chris Mason:
"Outside of our usual batch of fixes, this integrates the subvolume
quota updates that Qu Wenruo from Fujitsu has been working on for a
few releases now. He gets an extra gold star for making btrfs smaller
this time, and fixing a number of quota corners in the process.
Dave Sterba tested and integrated Anand Jain's sysfs improvements.
Outside of exporting a symbol (ack'd by Greg) these are all internal
to btrfs and it's mostly cleanups and fixes. Anand also attached some
of our sysfs objects to our internal device management structs instead
of an object off the super block. It will make device management
easier overall and it's a better fit for how the sysfs files are used.
None of the existing sysfs files are moved around.
Thanks for all the fixes everyone"
* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (87 commits)
btrfs: delayed-ref: double free in btrfs_add_delayed_tree_ref()
Btrfs: Check if kobject is initialized before put
lib: export symbol kobject_move()
Btrfs: sysfs: add support to show replacing target in the sysfs
Btrfs: free the stale device
Btrfs: use received_uuid of parent during send
Btrfs: fix use-after-free in btrfs_replay_log
btrfs: wait for delayed iputs on no space
btrfs: qgroup: Make snapshot accounting work with new extent-oriented qgroup.
btrfs: qgroup: Add the ability to skip given qgroup for old/new_roots.
btrfs: ulist: Add ulist_del() function.
btrfs: qgroup: Cleanup the old ref_node-oriented mechanism.
btrfs: qgroup: Switch self test to extent-oriented qgroup mechanism.
btrfs: qgroup: Switch to new extent-oriented qgroup mechanism.
btrfs: qgroup: Switch rescan to new mechanism.
btrfs: qgroup: Add new qgroup calculation function btrfs_qgroup_account_extents().
btrfs: backref: Add special time_seq == (u64)-1 case for btrfs_find_all_roots().
btrfs: qgroup: Add new function to record old_roots.
btrfs: qgroup: Record possible quota-related extent for qgroup.
btrfs: qgroup: Add function qgroup_update_counters().
...
After commit 4f764e5153 ("Btrfs: remove deleted xattrs on fsync log
replay"), we can end up in a situation where during log replay we end up
deleting xattrs that were never deleted when their file was last fsynced.
This happens in the fast fsync path (flag BTRFS_INODE_NEEDS_FULL_SYNC is
not set in the inode) if the inode has the flag BTRFS_INODE_COPY_EVERYTHING
set, the xattr was added in a past transaction and the leaf where the
xattr is located was not updated (COWed or created) in the current
transaction. In this scenario the xattr item never ends up in the log
tree and therefore at log replay time, which makes the replay code delete
the xattr from the fs/subvol tree as it thinks that xattr was deleted
prior to the last fsync.
Fix this by always logging all xattrs, which is the simplest and most
reliable way to detect deleted xattrs and replay the deletes at log replay
time.
This issue is reproducible with the following test case for fstests:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
here=`pwd`
tmp=/tmp/$$
status=1 # failure is the default!
_cleanup()
{
_cleanup_flakey
rm -f $tmp.*
}
trap "_cleanup; exit \$status" 0 1 2 3 15
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
. ./common/attr
# real QA test starts here
# We create a lot of xattrs for a single file. Only btrfs and xfs are currently
# able to store such a large mount of xattrs per file, other filesystems such
# as ext3/4 and f2fs for example, fail with ENOSPC even if we attempt to add
# less than 1000 xattrs with very small values.
_supported_fs btrfs xfs
_supported_os Linux
_need_to_be_root
_require_scratch
_require_dm_flakey
_require_attrs
_require_metadata_journaling $SCRATCH_DEV
rm -f $seqres.full
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create the test file with some initial data and make sure everything is
# durably persisted.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 32k" $SCRATCH_MNT/foo | _filter_xfs_io
sync
# Add many small xattrs to our file.
# We create such a large amount because it's needed to trigger the issue found
# in btrfs - we need to have an amount that causes the fs to have at least 3
# btree leafs with xattrs stored in them, and it must work on any leaf size
# (maximum leaf/node size is 64Kb).
num_xattrs=2000
for ((i = 1; i <= $num_xattrs; i++)); do
name="user.attr_$(printf "%04d" $i)"
$SETFATTR_PROG -n $name -v "val_$(printf "%04d" $i)" $SCRATCH_MNT/foo
done
# Sync the filesystem to force a commit of the current btrfs transaction, this
# is a necessary condition to trigger the bug on btrfs.
sync
# Now update our file's data and fsync the file.
# After a successful fsync, if the fsync log/journal is replayed we expect to
# see all the xattrs we added before with the same values (and the updated file
# data of course). Btrfs used to delete some of these xattrs when it replayed
# its fsync log/journal.
$XFS_IO_PROG -c "pwrite -S 0xbb 8K 16K" \
-c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again and mount. This makes the fs replay its fsync log.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
echo "File content after crash and log replay:"
od -t x1 $SCRATCH_MNT/foo
echo "File xattrs after crash and log replay:"
for ((i = 1; i <= $num_xattrs; i++)); do
name="user.attr_$(printf "%04d" $i)"
echo -n "$name="
$GETFATTR_PROG --absolute-names -n $name --only-values $SCRATCH_MNT/foo
echo
done
status=0
exit
The golden output expects all xattrs to be available, and with the correct
values, after the fsync log is replayed.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we do an append write to a file (which increases its inode's i_size)
that does not have the flag BTRFS_INODE_NEEDS_FULL_SYNC set in its inode,
and the previous transaction added a new hard link to the file, which sets
the flag BTRFS_INODE_COPY_EVERYTHING in the file's inode, and then fsync
the file, the inode's new i_size isn't logged. This has the consequence
that after the fsync log is replayed, the file size remains what it was
before the append write operation, which means users/applications will
not be able to read the data that was successsfully fsync'ed before.
This happens because neither the inode item nor the delayed inode get
their i_size updated when the append write is made - doing so would
require starting a transaction in the buffered write path, something that
we do not do intentionally for performance reasons.
Fix this by making sure that when the flag BTRFS_INODE_COPY_EVERYTHING is
set the inode is logged with its current i_size (log the in-memory inode
into the log tree).
This issue is not a recent regression and is easy to reproduce with the
following test case for fstests:
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"
here=`pwd`
tmp=/tmp/$$
status=1 # failure is the default!
_cleanup()
{
_cleanup_flakey
rm -f $tmp.*
}
trap "_cleanup; exit \$status" 0 1 2 3 15
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
# real QA test starts here
_supported_fs generic
_supported_os Linux
_need_to_be_root
_require_scratch
_require_dm_flakey
_require_metadata_journaling $SCRATCH_DEV
_crash_and_mount()
{
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Allow writes again and mount. This makes the fs replay its fsync log.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
}
rm -f $seqres.full
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create the test file with some initial data and then fsync it.
# The fsync here is only needed to trigger the issue in btrfs, as it causes the
# the flag BTRFS_INODE_NEEDS_FULL_SYNC to be removed from the btrfs inode.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 32k" \
-c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
sync
# Add a hard link to our file.
# On btrfs this sets the flag BTRFS_INODE_COPY_EVERYTHING on the btrfs inode,
# which is a necessary condition to trigger the issue.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/bar
# Sync the filesystem to force a commit of the current btrfs transaction, this
# is a necessary condition to trigger the bug on btrfs.
sync
# Now append more data to our file, increasing its size, and fsync the file.
# In btrfs because the inode flag BTRFS_INODE_COPY_EVERYTHING was set and the
# write path did not update the inode item in the btree nor the delayed inode
# item (in memory struture) in the current transaction (created by the fsync
# handler), the fsync did not record the inode's new i_size in the fsync
# log/journal. This made the data unavailable after the fsync log/journal is
# replayed.
$XFS_IO_PROG -c "pwrite -S 0xbb 32K 32K" \
-c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
echo "File content after fsync and before crash:"
od -t x1 $SCRATCH_MNT/foo
_crash_and_mount
echo "File content after crash and log replay:"
od -t x1 $SCRATCH_MNT/foo
status=0
exit
The expected file output before and after the crash/power failure expects the
appended data to be available, which is:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0100000 bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
*
0200000
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
While the inode cache caching kthread is calling btrfs_unpin_free_ino(),
we could have a concurrent call to btrfs_return_ino() that adds a new
entry to the root's free space cache of pinned inodes. This concurrent
call does not acquire the fs_info->commit_root_sem before adding a new
entry if the caching state is BTRFS_CACHE_FINISHED, which is a problem
because the caching kthread calls btrfs_unpin_free_ino() after setting
the caching state to BTRFS_CACHE_FINISHED and therefore races with
the task calling btrfs_return_ino(), which is adding a new entry, while
the former (caching kthread) is navigating the cache's rbtree, removing
and freeing nodes from the cache's rbtree without acquiring the spinlock
that protects the rbtree.
This race resulted in memory corruption due to double free of struct
btrfs_free_space objects because both tasks can end up doing freeing the
same objects. Note that adding a new entry can result in merging it with
other entries in the cache, in which case those entries are freed.
This is particularly important as btrfs_free_space structures are also
used for the block group free space caches.
This memory corruption can be detected by a debugging kernel, which
reports it with the following trace:
[132408.501148] slab error in verify_redzone_free(): cache `btrfs_free_space': double free detected
[132408.505075] CPU: 15 PID: 12248 Comm: btrfs-ino-cache Tainted: G W 4.1.0-rc5-btrfs-next-10+ #1
[132408.505075] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
[132408.505075] ffff880023e7d320 ffff880163d73cd8 ffffffff8145eec7 ffffffff81095dce
[132408.505075] ffff880009735d40 ffff880163d73ce8 ffffffff81154e1e ffff880163d73d68
[132408.505075] ffffffff81155733 ffffffffa054a95a ffff8801b6099f00 ffffffffa0505b5f
[132408.505075] Call Trace:
[132408.505075] [<ffffffff8145eec7>] dump_stack+0x4f/0x7b
[132408.505075] [<ffffffff81095dce>] ? console_unlock+0x356/0x3a2
[132408.505075] [<ffffffff81154e1e>] __slab_error.isra.28+0x25/0x36
[132408.505075] [<ffffffff81155733>] __cache_free+0xe2/0x4b6
[132408.505075] [<ffffffffa054a95a>] ? __btrfs_add_free_space+0x2f0/0x343 [btrfs]
[132408.505075] [<ffffffffa0505b5f>] ? btrfs_unpin_free_ino+0x8e/0x99 [btrfs]
[132408.505075] [<ffffffff810f3b30>] ? time_hardirqs_off+0x15/0x28
[132408.505075] [<ffffffff81084d42>] ? trace_hardirqs_off+0xd/0xf
[132408.505075] [<ffffffff811563a1>] ? kfree+0xb6/0x14e
[132408.505075] [<ffffffff811563d0>] kfree+0xe5/0x14e
[132408.505075] [<ffffffffa0505b5f>] btrfs_unpin_free_ino+0x8e/0x99 [btrfs]
[132408.505075] [<ffffffffa0505e08>] caching_kthread+0x29e/0x2d9 [btrfs]
[132408.505075] [<ffffffffa0505b6a>] ? btrfs_unpin_free_ino+0x99/0x99 [btrfs]
[132408.505075] [<ffffffff8106698f>] kthread+0xef/0xf7
[132408.505075] [<ffffffff810f3b08>] ? time_hardirqs_on+0x15/0x28
[132408.505075] [<ffffffff810668a0>] ? __kthread_parkme+0xad/0xad
[132408.505075] [<ffffffff814653d2>] ret_from_fork+0x42/0x70
[132408.505075] [<ffffffff810668a0>] ? __kthread_parkme+0xad/0xad
[132408.505075] ffff880023e7d320: redzone 1:0x9f911029d74e35b, redzone 2:0x9f911029d74e35b.
[132409.501654] slab: double free detected in cache 'btrfs_free_space', objp ffff880023e7d320
[132409.503355] ------------[ cut here ]------------
[132409.504241] kernel BUG at mm/slab.c:2571!
Therefore fix this by having btrfs_unpin_free_ino() acquire the lock
that protects the rbtree while doing the searches and removing entries.
Fixes: 1c70d8fb4d ("Btrfs: fix inode caching vs tree log")
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The free space entries are allocated using kmem_cache_zalloc(),
through __btrfs_add_free_space(), therefore we should use
kmem_cache_free() and not kfree() to avoid any confusion and
any potential problem. Looking at the kfree() definition at
mm/slab.c it has the following comment:
/*
* (...)
*
* Don't free memory not originally allocated by kmalloc()
* or you will run into trouble.
*/
So better be safe and use kmem_cache_free().
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Although it is a rare case, we'd better free previous allocated
memory on error.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
It is introduced by:
c404e0dc2c
Btrfs: fix use-after-free in the finishing procedure of the device replace
But seems no relationship with that bug, this patch revirt these
code block for cleanup.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently, we can only set a limitation on a qgroup, but we
can not clear it.
This patch provide a choice to user to clear a limitation on
qgroup by passing a value of CLEAR_VALUE(-1) to kernel.
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull core block IO update from Jens Axboe:
"Nothing really major in here, mostly a collection of smaller
optimizations and cleanups, mixed with various fixes. In more detail,
this contains:
- Addition of policy specific data to blkcg for block cgroups. From
Arianna Avanzini.
- Various cleanups around command types from Christoph.
- Cleanup of the suspend block I/O path from Christoph.
- Plugging updates from Shaohua and Jeff Moyer, for blk-mq.
- Eliminating atomic inc/dec of both remaining IO count and reference
count in a bio. From me.
- Fixes for SG gap and chunk size support for data-less (discards)
IO, so we can merge these better. From me.
- Small restructuring of blk-mq shared tag support, freeing drivers
from iterating hardware queues. From Keith Busch.
- A few cfq-iosched tweaks, from Tahsin Erdogan and me. Makes the
IOPS mode the default for non-rotational storage"
* 'for-4.2/core' of git://git.kernel.dk/linux-block: (35 commits)
cfq-iosched: fix other locations where blkcg_to_cfqgd() can return NULL
cfq-iosched: fix sysfs oops when attempting to read unconfigured weights
cfq-iosched: move group scheduling functions under ifdef
cfq-iosched: fix the setting of IOPS mode on SSDs
blktrace: Add blktrace.c to BLOCK LAYER in MAINTAINERS file
block, cgroup: implement policy-specific per-blkcg data
block: Make CFQ default to IOPS mode on SSDs
block: add blk_set_queue_dying() to blkdev.h
blk-mq: Shared tag enhancements
block: don't honor chunk sizes for data-less IO
block: only honor SG gap prevention for merges that contain data
block: fix returnvar.cocci warnings
block, dm: don't copy bios for request clones
block: remove management of bi_remaining when restoring original bi_end_io
block: replace trylock with mutex_lock in blkdev_reread_part()
block: export blkdev_reread_part() and __blkdev_reread_part()
suspend: simplify block I/O handling
block: collapse bio bit space
block: remove unused BIO_RW_BLOCK and BIO_EOF flags
block: remove BIO_EOPNOTSUPP
...
There is a cut and paste error so instead of freeing "head_ref", we free
"ref" twice.
Fixes: 3368d001ba ('btrfs: qgroup: Record possible quota-related extent for qgroup.')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
file_remove_suid() is a misnomer since it removes also file capabilities
stored in xattrs and sets S_NOSEC flag. Also should_remove_suid() tells
something else than whether file_remove_suid() call is necessary which
leads to bugs.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch will add support to show the replacing target in sysfs
during the process of replacement.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
When btrfs on a device is overwritten with a new btrfs (mkfs),
the old btrfs instance in the kernel becomes stale. So with this
patch, if kernel finds device is overwritten then delete the stale
fsid/uuid.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Neil Horman pointed out a problem where if he did something like this
receive A
snap A B
change B
send -p A B
and then on another box do
recieve A
receive B
the receive B would fail because we use the UUID of A for the clone sources for
B. This makes sense most of the time because normally you are sending from the
original sources, not a received source. However when you use a recieved subvol
its UUID is going to be something completely different, so if you then try to
receive the diff on a different volume it won't find the UUID because the new A
will be something else. The only constant is the received uuid. So instead
check to see if we have received_uuid set on the root, and if so use that as the
clone source, as btrfs receive looks for matches either in received_uuid or
uuid. Thanks,
Reported-by: Neil Horman <nhorman@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: Chris Mason <clm@fb.com>
@log_root_tree should not be referenced after kfree.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs will report no_space when we run following write and delete
file loop:
# FILE_SIZE_M=[ 75% of fs space ]
# DEV=[ some dev ]
# MNT=[ some dir ]
#
# mkfs.btrfs -f "$DEV"
# mount -o nodatacow "$DEV" "$MNT"
# for ((i = 0; i < 100; i++)); do dd if=/dev/zero of="$MNT"/file0 bs=1M count="$FILE_SIZE_M"; rm -f "$MNT"/file0; done
#
Reason:
iput() and evict() is run after write pages to block device, if
write pages work is not finished before next write, the "rm"ed space
is not freed, and caused above bug.
Fix:
We can add "-o flushoncommit" mount option to avoid above bug, but
it have performance problem. Actually, we can to wait for on-the-fly
writes only when no-space happened, it is which this patch do.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
qgroup.
Make snapshot accounting work with new extent-oriented mechanism by
skipping given root in new/old_roots in create_pending_snapshot().
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This is used by later qgroup fix patches for snapshot.
As current snapshot accounting is done by btrfs_qgroup_inherit(), but
new extent oriented quota mechanism will account extent from
btrfs_copy_root() and other snapshot things, causing wrong result.
So add this ability to handle snapshot accounting.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This function will delete unode with given (val,aux) pair.
And with this patch, seqnum for debug usage doesn't have any meaning
now, so remove them.
This is used by later patches to skip snapshot root.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Since the self test transaction don't have delayed_ref_roots, so use
find_all_roots() and export btrfs_qgroup_account_extent() to simulate it
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Switch from old ref_node based qgroup to extent based qgroup mechanism
for normal operations.
The new mechanism should hugely reduce the overhead of btrfs quota
system, and further more, the codes and logic should be more clean and
easier to maintain.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Switch rescan to use the new new extent oriented mechanism.
As rescan is also based on extent, new mechanism is just a perfect match
for rescan.
With re-designed internal functions, rescan is quite easy, just call
btrfs_find_all_roots() and then btrfs_qgroup_account_one_extent().
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_qgroup_account_extents().
The new btrfs_qgroup_account_extents() function should be called in
btrfs_commit_transaction() and it will update all the qgroup according
to delayed_ref_root->dirty_extent_root.
The new function can handle both normal operation during
commit_transaction() or in rescan in a unified method with clearer
logic.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_find_all_roots().
Allow btrfs_find_all_roots() to skip all delayed_ref_head lock and tree
lock to do tree search.
This is important for later qgroup implement which will call
find_all_roots() after fs trees are committed.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Add function btrfs_qgroup_prepare_account_extents() to get old_roots
which are needed for qgroup.
We do it in commit_transaction() and before switch_roots(), and only
search commit_root, so it gives a quite accurate view for previous
transaction.
With old_roots from previous transaction, we can use it to do accurate
account with current transaction.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Add hook in add_delayed_ref_head() to record quota-related extent record
into delayed_ref_root->dirty_extent_record rb-tree for later qgroup
accounting.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Add function qgroup_update_counters(), which will update related
qgroups' rfer/excl according to old/new_roots.
This is one of the two core functions for the new qgroup implement.
This is based on btrfs_adjust_coutners() but with clearer logic and
comment.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This function is used to update refcnt for qgroups.
And is one of the two core functions used in the new qgroup implement.
This is based on the old update_old/new_refcnt, but provides a unified
logic and behavior.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
__btrfs_inc_extent_ref() and __btrfs_free_extent() have already had too
many parameters, but three of them can be extracted from
btrfs_delayed_ref_node struct.
So use btrfs_delayed_ref_node struct as a single parameter to replace
the bytenr/num_byte/no_quota parameters.
The real objective of this patch is to allow btrfs_qgroup_record_ref()
get the delayed_ref_node in incoming qgroup patches.
Other functions calling btrfs_qgroup_record_ref() are not affected since
the rest will only add/sub exclusive extents, where node is not used.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Use inline functions to do such things, to improve readability.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Acked-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Cleanup the rb_tree merge/insert/update functions, since now we use list
instead of rb_tree now.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This patch replace the rbtree used in ref_head to list.
This has the following advantage:
1) Easier merge logic.
With the new list implement, we only need to care merging the tail
ref_node with the new ref_node.
And this can be done quite easy at insert time, no need to do a
indicated merge at run_delayed_refs().
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Old __merge_refs() in backref.c will even merge refs whose root_id are
different, which makes qgroup gives wrong result.
Fix it by checking ref_for_same_block() before any mode specific works.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
lockdep report following warning in test:
[25176.843958] =================================
[25176.844519] [ INFO: inconsistent lock state ]
[25176.845047] 4.1.0-rc3 #22 Tainted: G W
[25176.845591] ---------------------------------
[25176.846153] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[25176.846713] fsstress/26661 [HC0[0]:SC1[1]:HE1:SE0] takes:
[25176.847246] (&wr_ctx->wr_lock){+.?...}, at: [<ffffffffa04cdc6d>] scrub_free_ctx+0x2d/0xf0 [btrfs]
[25176.847838] {SOFTIRQ-ON-W} state was registered at:
[25176.848396] [<ffffffff810bf460>] __lock_acquire+0x6a0/0xe10
[25176.848955] [<ffffffff810bfd1e>] lock_acquire+0xce/0x2c0
[25176.849491] [<ffffffff816489af>] mutex_lock_nested+0x7f/0x410
[25176.850029] [<ffffffffa04d04ff>] scrub_stripe+0x4df/0x1080 [btrfs]
[25176.850575] [<ffffffffa04d11b1>] scrub_chunk.isra.19+0x111/0x130 [btrfs]
[25176.851110] [<ffffffffa04d144c>] scrub_enumerate_chunks+0x27c/0x510 [btrfs]
[25176.851660] [<ffffffffa04d3b87>] btrfs_scrub_dev+0x1c7/0x6c0 [btrfs]
[25176.852189] [<ffffffffa04e918e>] btrfs_dev_replace_start+0x36e/0x450 [btrfs]
[25176.852771] [<ffffffffa04a98e0>] btrfs_ioctl+0x1e10/0x2d20 [btrfs]
[25176.853315] [<ffffffff8121c5b8>] do_vfs_ioctl+0x318/0x570
[25176.853868] [<ffffffff8121c851>] SyS_ioctl+0x41/0x80
[25176.854406] [<ffffffff8164da17>] system_call_fastpath+0x12/0x6f
[25176.854935] irq event stamp: 51506
[25176.855511] hardirqs last enabled at (51506): [<ffffffff810d4ce5>] vprintk_emit+0x225/0x5e0
[25176.856059] hardirqs last disabled at (51505): [<ffffffff810d4b77>] vprintk_emit+0xb7/0x5e0
[25176.856642] softirqs last enabled at (50886): [<ffffffff81067a23>] __do_softirq+0x363/0x640
[25176.857184] softirqs last disabled at (50949): [<ffffffff8106804d>] irq_exit+0x10d/0x120
[25176.857746]
other info that might help us debug this:
[25176.858845] Possible unsafe locking scenario:
[25176.859981] CPU0
[25176.860537] ----
[25176.861059] lock(&wr_ctx->wr_lock);
[25176.861705] <Interrupt>
[25176.862272] lock(&wr_ctx->wr_lock);
[25176.862881]
*** DEADLOCK ***
Reason:
Above warning is caused by:
Interrupt
-> bio_endio()
-> ...
-> scrub_put_ctx()
-> scrub_free_ctx() *1
-> ...
-> mutex_lock(&wr_ctx->wr_lock);
scrub_put_ctx() is allowed to be called in end_bio interrupt, but
in code design, it will never call scrub_free_ctx(sctx) in interrupe
context(above *1), because btrfs_scrub_dev() get one additional
reference of sctx->refs, which makes scrub_free_ctx() only called
withine btrfs_scrub_dev().
Now the code runs out of our wish, because free sequence in
scrub_pending_bio_dec() have a gap.
Current code:
-----------------------------------+-----------------------------------
scrub_pending_bio_dec() | btrfs_scrub_dev
-----------------------------------+-----------------------------------
atomic_dec(&sctx->bios_in_flight); |
wake_up(&sctx->list_wait); |
| scrub_put_ctx()
| -> atomic_dec_and_test(&sctx->refs)
scrub_put_ctx(sctx); |
-> atomic_dec_and_test(&sctx->refs)|
-> scrub_free_ctx() |
-----------------------------------+-----------------------------------
We expected:
-----------------------------------+-----------------------------------
scrub_pending_bio_dec() | btrfs_scrub_dev
-----------------------------------+-----------------------------------
atomic_dec(&sctx->bios_in_flight); |
wake_up(&sctx->list_wait); |
scrub_put_ctx(sctx); |
-> atomic_dec_and_test(&sctx->refs)|
| scrub_put_ctx()
| -> atomic_dec_and_test(&sctx->refs)
| -> scrub_free_ctx()
-----------------------------------+-----------------------------------
Fix:
Move scrub_pending_bio_dec() to a workqueue, to avoid this function run
in interrupt context.
Tested by check tracelog in debug.
Changelog v1->v2:
Use workqueue instead of adjust function call sequence in v1,
because v1 will introduce a bug pointed out by:
Filipe David Manana <fdmanana@gmail.com>
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The extent-same code rejects requests with an unaligned length. This
poses a problem when we want to dedupe the tail extent of files as we
skip cloning the portion between i_size and the extent boundary.
If we don't clone the entire extent, it won't be deleted. So the
combination of these behaviors winds up giving us worst-case dedupe on
many files.
We can fix this by allowing a length that extents to i_size and
internally aligining those to the end of the block. This is what
btrfs_ioctl_clone() so we can just copy that check over.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
max_to_defrag represents the number of pages to defrag rather than the last
page of the file range to be defragged.
Consider a file having 10 4k blocks (i.e. blocks in the range [0 - 9]). If the
defrag ioctl was invoked for the block range [3 - 6], then max_to_defrag
should actually have the value 4. Instead in the current code we end up
setting it to 6.
Now, this does not (yet) cause an issue since the first part of the while loop
condition in btrfs_defrag_file() (i.e. "i <= last_index") causes the control
to flow out of the while loop before any buggy behavior is actually caused. So
the patch just makes sure that max_to_defrag ends up having the right value
rather than fixing a bug. I did run the xfstests suite to make sure that the
code does not regress.
Changelog: v1->v2:
Provide a much descriptive commit message.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Chris Mason <clm@fb.com>
Read-ahead is done for the pages in the range [ra_index, ra_index + cluster -
1]. So the next read-ahead should be starting from the page at index 'ra_index
+ cluster' (unless we deemed that the extent at 'ra_index + cluster' as
non-defraggable) rather than from the page at index 'ra_index +
max_cluster'. This patch fixes this. I did run the xfstests suite to make sure
that the code does not regress.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Chris Mason <clm@fb.com>
When allocating a new chunk or removing one we need to update num_devs
device items and insert or remove a chunk item in the chunk tree, so
in the worst case the space needed in the chunk space_info is:
btrfs_calc_trunc_metadata_size(chunk_root, num_devs) +
btrfs_calc_trans_metadata_size(chunk_root, 1)
That is, in the worst case we need to cow num_devs paths and cow 1 other
path that can result in splitting every node and leaf, and each path
consisting of BTRFS_MAX_LEVEL - 1 nodes and 1 leaf. We were requiring
some additional chunk_root->nodesize * BTRFS_MAX_LEVEL * num_devs bytes,
which were unnecessary since updating the existing device items does
not result in splitting the nodes and leaf since after updating them
they remain with the same size.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We don't need to attach ordered extents that have completed to the current
transaction. Doing so only makes us hold memory for longer than necessary
and delaying the iput of the inode until the transaction is committed (for
each created ordered extent we do an igrab and then schedule an asynchronous
iput when the ordered extent's reference count drops to 0), preventing the
inode from being evictable until the transaction commits.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit 3a8b36f378 ("Btrfs: fix data loss in the fast fsync path") added
a performance regression for that causes an unnecessary sync of the log
trees (fs/subvol and root log trees) when 2 consecutive fsyncs are done
against a file, without no writes or any metadata updates to the inode in
between them and if a transaction is committed before the second fsync is
called.
Huang Ying reported this to lkml (https://lkml.org/lkml/2015/3/18/99)
after a test sysbench test that measured a -62% decrease of file io
requests per second for that tests' workload.
The test is:
echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu2/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu3/cpufreq/scaling_governor
mkfs -t btrfs /dev/sda2
mount -t btrfs /dev/sda2 /fs/sda2
cd /fs/sda2
for ((i = 0; i < 1024; i++)); do fallocate -l 67108864 testfile.$i; done
sysbench --test=fileio --max-requests=0 --num-threads=4 --max-time=600 \
--file-test-mode=rndwr --file-total-size=68719476736 --file-io-mode=sync \
--file-num=1024 run
A test on kvm guest, running a debug kernel gave me the following results:
Without 3a8b36f378: 16.01 reqs/sec
With 3a8b36f378: 3.39 reqs/sec
With 3a8b36f378 and this patch: 16.04 reqs/sec
Reported-by: Huang Ying <ying.huang@intel.com>
Tested-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Zygo Blaxell and other users have reported occasional hangs while an
inode is being evicted, leading to traces like the following:
[ 5281.972322] INFO: task rm:20488 blocked for more than 120 seconds.
[ 5281.973836] Not tainted 4.0.0-rc5-btrfs-next-9+ #2
[ 5281.974818] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 5281.976364] rm D ffff8800724cfc38 0 20488 7747 0x00000000
[ 5281.977506] ffff8800724cfc38 ffff8800724cfc38 ffff880065da5c50 0000000000000001
[ 5281.978461] ffff8800724cffd8 ffff8801540a5f50 0000000000000008 ffff8801540a5f78
[ 5281.979541] ffff8801540a5f50 ffff8800724cfc58 ffffffff8143107e 0000000000000123
[ 5281.981396] Call Trace:
[ 5281.982066] [<ffffffff8143107e>] schedule+0x74/0x83
[ 5281.983341] [<ffffffffa03b33cf>] wait_on_state+0xac/0xcd [btrfs]
[ 5281.985127] [<ffffffff81075cd6>] ? signal_pending_state+0x31/0x31
[ 5281.986715] [<ffffffffa03b4b71>] wait_extent_bit.constprop.32+0x7c/0xde [btrfs]
[ 5281.988680] [<ffffffffa03b540b>] lock_extent_bits+0x5d/0x88 [btrfs]
[ 5281.990200] [<ffffffffa03a621d>] btrfs_evict_inode+0x24e/0x5be [btrfs]
[ 5281.991781] [<ffffffff8116964d>] evict+0xa0/0x148
[ 5281.992735] [<ffffffff8116a43d>] iput+0x18f/0x1e5
[ 5281.993796] [<ffffffff81160d4a>] do_unlinkat+0x15b/0x1fa
[ 5281.994806] [<ffffffff81435b54>] ? ret_from_sys_call+0x1d/0x58
[ 5281.996120] [<ffffffff8107d314>] ? trace_hardirqs_on_caller+0x18f/0x1ab
[ 5281.997562] [<ffffffff8123960b>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 5281.998815] [<ffffffff81161a16>] SyS_unlinkat+0x29/0x2b
[ 5281.999920] [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[ 5282.001299] 1 lock held by rm/20488:
[ 5282.002066] #0: (sb_writers#12){.+.+.+}, at: [<ffffffff8116dd81>] mnt_want_write+0x24/0x4b
This happens when we have readahead, which calls readpages(), happening
right before the inode eviction handler is invoked. So the reason is
essentially:
1) readpages() is called while a reference on the inode is held, so
eviction can not be triggered before readpages() returns. It also
locks one or more ranges in the inode's io_tree (which is done at
extent_io.c:__do_contiguous_readpages());
2) readpages() submits several read bios, all with an end io callback
that runs extent_io.c:end_bio_extent_readpage() and that is executed
by other task when a bio finishes, corresponding to a work queue
(fs_info->end_io_workers) worker kthread. This callback unlocks
the ranges in the inode's io_tree that were previously locked in
step 1;
3) readpages() returns, the reference on the inode is dropped;
4) One or more of the read bios previously submitted are still not
complete (their end io callback was not yet invoked or has not
yet finished execution);
5) Inode eviction is triggered (through an unlink call for example).
The inode reference count was not incremented before submitting
the read bios, therefore this is possible;
6) The eviction handler starts executing and enters the loop that
iterates over all extent states in the inode's io_tree;
7) The loop picks one extent state record and uses its ->start and
->end fields, after releasing the inode's io_tree spinlock, to
call lock_extent_bits() and clear_extent_bit(). The call to lock
the range [state->start, state->end] blocks because the whole
range or a part of it was locked by the previous call to
readpages() and the corresponding end io callback, which unlocks
the range was not yet executed;
8) The end io callback for the read bio is executed and unlocks the
range [state->start, state->end] (or a superset of that range).
And at clear_extent_bit() the extent_state record state is used
as a second argument to split_state(), which sets state->start to
a larger value;
9) The task executing the eviction handler is woken up by the task
executing the bio's end io callback (through clear_state_bit) and
the eviction handler locks the range
[old value for state->start, state->end]. Shortly after, when
calling clear_extent_bit(), it unlocks the range
[new value for state->start, state->end], so it ends up unlocking
only part of the range that it locked, leaving an extent state
record in the io_tree that represents the unlocked subrange;
10) The eviction handler loop, in its next iteration, gets the
extent_state record for the subrange that it did not unlock in the
previous step and then tries to lock it, resulting in an hang.
So fix this by not using the ->start and ->end fields of an existing
extent_state record. This is a simple solution, and an alternative
could be to bump the inode's reference count before submitting each
read bio and having it dropped in the bio's end io callback. But that
would be a more invasive/complex change and would not protect against
other possible places that are not holding a reference on the inode
as well. Something to consider in the future.
Many thanks to Zygo Blaxell for reporting, in the mailing list, the
issue, a set of scripts to trigger it and testing this fix.
Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Tested-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The return value of read_tree_block() can confuse callers as it always
returns NULL for either -ENOMEM or -EIO, so it's likely that callers
parse it to a wrong error, for instance, in btrfs_read_tree_root().
This fixes the above issue.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
read_tree_block may take a reference on the 'eb', a following
free_extent_buffer is necessary.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
After commit 8407f55326
("Btrfs: fix data corruption after fast fsync and writeback error"),
during wait_ordered_extents(), we wait for ordered extent setting
BTRFS_ORDERED_IO_DONE or BTRFS_ORDERED_IOERR, at which point we've
already got checksum information, so we don't need to check
(csum_bytes_left == 0) in the whole logging path.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Unlike when attempting to allocate a new block group, where we check
that we have enough space in the system space_info to update the device
items and insert a new chunk item in the chunk tree, we were not checking
if the system space_info had enough space for updating the device items
and deleting the chunk item in the chunk tree. This often lead to -ENOSPC
error when attempting to allocate blocks for the chunk tree (during btree
node/leaf COW operations) while updating the device items or deleting the
chunk item, which resulted in the current transaction being aborted and
turning the filesystem into read-only mode.
While running fstests generic/038, which stresses allocation of block
groups and removal of unused block groups, with a large scratch device
(750Gb) this happened often, despite more than enough unallocated space,
and resulted in the following trace:
[68663.586604] WARNING: CPU: 3 PID: 1521 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x114 [btrfs]()
[68663.600407] BTRFS: Transaction aborted (error -28)
(...)
[68663.730829] Call Trace:
[68663.732585] [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[68663.734334] [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[68663.739980] [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[68663.757153] [<ffffffffa036ca6d>] ? __btrfs_abort_transaction+0x52/0x114 [btrfs]
[68663.760925] [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[68663.762854] [<ffffffffa03b159d>] ? btrfs_update_device+0x15a/0x16c [btrfs]
[68663.764073] [<ffffffffa036ca6d>] __btrfs_abort_transaction+0x52/0x114 [btrfs]
[68663.765130] [<ffffffffa03b3638>] btrfs_remove_chunk+0x597/0x5ee [btrfs]
[68663.765998] [<ffffffffa0384663>] ? btrfs_delete_unused_bgs+0x245/0x296 [btrfs]
[68663.767068] [<ffffffffa0384676>] btrfs_delete_unused_bgs+0x258/0x296 [btrfs]
[68663.768227] [<ffffffff8143527f>] ? _raw_spin_unlock_irq+0x2d/0x4c
[68663.769081] [<ffffffffa038b109>] cleaner_kthread+0x13d/0x16c [btrfs]
[68663.799485] [<ffffffffa038afcc>] ? btrfs_alloc_root+0x28/0x28 [btrfs]
[68663.809208] [<ffffffff8105f367>] kthread+0xef/0xf7
[68663.828795] [<ffffffff810e603f>] ? time_hardirqs_on+0x15/0x28
[68663.844942] [<ffffffff8105f278>] ? __kthread_parkme+0xad/0xad
[68663.846486] [<ffffffff81435a88>] ret_from_fork+0x58/0x90
[68663.847760] [<ffffffff8105f278>] ? __kthread_parkme+0xad/0xad
[68663.849503] ---[ end trace 798477c6d6dbaad6 ]---
[68663.850525] BTRFS: error (device sdc) in btrfs_remove_chunk:2652: errno=-28 No space left
So fix this by verifying that enough space exists in system space_info,
and reserving the space in the chunk block reserve, before attempting to
delete the block group and allocate a new system chunk if we don't have
enough space to perform the necessary updates and delete in the chunk
tree. Like for the block group creation case, we don't error our if we
fail to allocate a new system chunk, since we might end up not needing
it (no node/leaf splits happen during the COW operations and/or we end
up not needing to COW any btree nodes or leafs because they were already
COWed in the current transaction and their writeback didn't start yet).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
While creating a block group, we often end up getting ENOSPC while updating
the chunk tree, which leads to a transaction abortion that produces a trace
like the following:
[30670.116368] WARNING: CPU: 4 PID: 20735 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x106 [btrfs]()
[30670.117777] BTRFS: Transaction aborted (error -28)
(...)
[30670.163567] Call Trace:
[30670.163906] [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[30670.164522] [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[30670.165171] [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[30670.166323] [<ffffffffa035daa7>] ? __btrfs_abort_transaction+0x52/0x106 [btrfs]
[30670.167213] [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[30670.167862] [<ffffffffa035daa7>] __btrfs_abort_transaction+0x52/0x106 [btrfs]
[30670.169116] [<ffffffffa03743d7>] btrfs_create_pending_block_groups+0x101/0x130 [btrfs]
[30670.170593] [<ffffffffa038426a>] __btrfs_end_transaction+0x84/0x366 [btrfs]
[30670.171960] [<ffffffffa038455c>] btrfs_end_transaction+0x10/0x12 [btrfs]
[30670.174649] [<ffffffffa036eb6b>] btrfs_check_data_free_space+0x11f/0x27c [btrfs]
[30670.176092] [<ffffffffa039450d>] btrfs_fallocate+0x7c8/0xb96 [btrfs]
[30670.177218] [<ffffffff812459f2>] ? __this_cpu_preempt_check+0x13/0x15
[30670.178622] [<ffffffff81152447>] vfs_fallocate+0x14c/0x1de
[30670.179642] [<ffffffff8116b915>] ? __fget_light+0x2d/0x4f
[30670.180692] [<ffffffff81152863>] SyS_fallocate+0x47/0x62
[30670.186737] [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[30670.187792] ---[ end trace 0373e6b491c4a8cc ]---
This is because we don't do proper space reservation for the chunk block
reserve when we have multiple tasks allocating chunks in parallel.
So block group creation has 2 phases, and the first phase essentially
checks if there is enough space in the system space_info, allocating a
new system chunk if there isn't, while the second phase updates the
device, extent and chunk trees. However, because the updates to the
chunk tree happen in the second phase, if we have N tasks, each with
its own transaction handle, allocating new chunks in parallel and if
there is only enough space in the system space_info to allocate M chunks,
where M < N, none of the tasks ends up allocating a new system chunk in
the first phase and N - M tasks will get -ENOSPC when attempting to
update the chunk tree in phase 2 if they need to COW any nodes/leafs
from the chunk tree.
Fix this by doing proper reservation in the chunk block reserve.
The issue could be reproduced by running fstests generic/038 in a loop,
which eventually triggered the problem.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Now that we're guaranteed to have a meaningful root dentry, we can just
export seq_dentry() and use it in btrfs_show_options(). The subvolume ID
is easy to get and can also be useful, so put that in there, too.
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently, mounting a subvolume with subvolid= takes a different code
path than mounting with subvol=. This isn't really a big deal except for
the fact that mounts done with subvolid= or the default subvolume don't
have a dentry that's connected to the dentry tree like in the subvol=
case. To unify the code paths, when given subvolid= or using the default
subvolume ID, translate it into a subvolume name by walking
ROOT_BACKREFs in the root tree and INODE_REFs in the filesystem trees.
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
There's nothing to stop a user from passing both subvol= and subvolid=
to mount, but if they don't refer to the same subvolume, someone is
going to be surprised at some point. Error out on this case, but allow
users to pass in both if they do match (which they could, for example,
get out of /proc/mounts).
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
In preparation for new functionality in mount_subvol(), give it
ownership of subvol_name and tidy up the error paths.
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently, setup_root_args() substitutes 's/subvol=[^,]*/subvolid=0/'.
But, this means that if the user passes both a subvol and subvolid for
some reason, we won't actually mount the top-level when we recursively
mount. For example, consider:
mkfs.btrfs -f /dev/sdb
mount /dev/sdb /mnt
btrfs subvol create /mnt/subvol1 # subvolid=257
btrfs subvol create /mnt/subvol2 # subvolid=258
umount /mnt
mount -osubvol=/subvol1,subvolid=258 /dev/sdb /mnt
In the final mount, subvol=/subvol1,subvolid=258 becomes
subvolid=0,subvolid=258, and the last option takes precedence, so we
mount subvol2 and try to look up subvol1 inside of it, which fails.
So, instead, do a thorough scan through the argument list and remove any
subvol= and subvolid= options, then append subvolid=0 to the end. This
implicitly makes subvol= take precedence over subvolid=, but we're about
to add a stricter check for that. This also makes setup_root_args() more
generic, which we'll need soon.
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
Since commit 0723a0473f ("btrfs: allow mounting btrfs subvolumes with
different ro/rw options"), when mounting a subvolume read/write when
another subvolume has previously been mounted read-only, we first do a
remount. However, this should be done with the superblock locked, as per
sync_filesystem():
/*
* We need to be protected against the filesystem going from
* r/o to r/w or vice versa.
*/
WARN_ON(!rwsem_is_locked(&sb->s_umount));
This WARN_ON can easily be hit with:
mkfs.btrfs -f /dev/vdb
mount /dev/vdb /mnt
btrfs subvol create /mnt/vol1
btrfs subvol create /mnt/vol2
umount /mnt
mount -oro,subvol=/vol1 /dev/vdb /mnt
mount -orw,subvol=/vol2 /dev/vdb /mnt2
Fixes: 0723a0473f ("btrfs: allow mounting btrfs subvolumes with different ro/rw options")
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we clear an extent state's EXTENT_LOCKED bit with clear_extent_bits()
through free_io_failure(), we weren't waking up any tasks waiting for the
extent's state EXTENT_LOCKED bit, leading to an hang.
So make sure clear_extent_bits() ends up waking up any waiters if the
bit EXTENT_LOCKED is supplied by its callers.
Zygo Blaxell was experiencing such hangs at inode eviction time after
file unlinks. Thanks to him for a set of scripts to reproduce the issue.
Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
With commit 1b98450816 ("Btrfs: fix find_free_dev_extent() malfunction
in case device tree has hole") introduced in the kernel 4.1 merge window,
we end up using part of a device hole for which there are already pending
chunks or pinned chunks. Before that commit we didn't use the hole and
would just move on to the next hole in the device.
However when we adjust the start offset for the chunk allocation and we
have pinned chunks, we set it blindly to the end offset of the pinned
chunk we are currently processing, which is dangerous because we can
have a pending chunk that has a start offset that matches the end offset
of our pinned chunk - leading us to a case where we end up getting two
pending chunks that start at the same physical device offset, which makes
us later abort the current transaction with -EEXIST when finishing the
chunk allocation at btrfs_create_pending_block_groups():
[194737.659017] ------------[ cut here ]------------
[194737.660192] WARNING: CPU: 15 PID: 31111 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x106 [btrfs]()
[194737.662209] BTRFS: Transaction aborted (error -17)
[194737.663175] Modules linked in: btrfs dm_snapshot dm_bufio dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse
[194737.674015] CPU: 15 PID: 31111 Comm: xfs_io Tainted: G W 4.0.0-rc5-btrfs-next-9+ #2
[194737.675986] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[194737.682999] 0000000000000009 ffff8800564c7a98 ffffffff8142fa46 ffffffff8108b6a2
[194737.684540] ffff8800564c7ae8 ffff8800564c7ad8 ffffffff81045ea5 ffff8800564c7b78
[194737.686017] ffffffffa0383aa7 00000000ffffffef ffff88000c7ba000 ffff8801a1f66f40
[194737.687509] Call Trace:
[194737.688068] [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[194737.689027] [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[194737.690095] [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[194737.691198] [<ffffffffa0383aa7>] ? __btrfs_abort_transaction+0x52/0x106 [btrfs]
[194737.693789] [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[194737.695065] [<ffffffffa0383aa7>] __btrfs_abort_transaction+0x52/0x106 [btrfs]
[194737.696806] [<ffffffffa039a3bd>] btrfs_create_pending_block_groups+0x101/0x130 [btrfs]
[194737.698683] [<ffffffffa03aa433>] __btrfs_end_transaction+0x84/0x366 [btrfs]
[194737.700329] [<ffffffffa03aa725>] btrfs_end_transaction+0x10/0x12 [btrfs]
[194737.701924] [<ffffffffa0394b51>] btrfs_check_data_free_space+0x11f/0x27c [btrfs]
[194737.703675] [<ffffffffa03b8ba4>] __btrfs_buffered_write+0x16a/0x4c8 [btrfs]
[194737.705417] [<ffffffffa03bb502>] ? btrfs_file_write_iter+0x19a/0x431 [btrfs]
[194737.707058] [<ffffffffa03bb511>] ? btrfs_file_write_iter+0x1a9/0x431 [btrfs]
[194737.708560] [<ffffffffa03bb68d>] btrfs_file_write_iter+0x325/0x431 [btrfs]
[194737.710673] [<ffffffff81067d85>] ? get_parent_ip+0xe/0x3e
[194737.712076] [<ffffffff811534c3>] new_sync_write+0x7c/0xa0
[194737.713293] [<ffffffff81153b58>] vfs_write+0xb2/0x117
[194737.714443] [<ffffffff81154424>] SyS_pwrite64+0x64/0x82
[194737.715646] [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[194737.717175] ---[ end trace f2d5dc04e56d7e48 ]---
[194737.718170] BTRFS: error (device sdc) in btrfs_create_pending_block_groups:9524: errno=-17 Object already exists
The -EEXIST failure comes from btrfs_finish_chunk_alloc(), called by
btrfs_create_pending_block_groups(), when it attempts to insert a
duplicated device extent item via btrfs_alloc_dev_extent().
This issue was reproducible with fstests generic/038 running in a loop for
several hours (it's very hard to hit) and using MOUNT_OPTIONS="-o discard".
Applying Jeff's recent patch titled "btrfs: add missing discards when
unpinning extents with -o discard" makes the issue much easier to reproduce
(usually within 4 to 5 hours), since it pins chunks for longer periods of
time when an unused block group is deleted by the cleaner kthread.
Fix this by making sure that we never adjust the start offset to a lower
value than it currently has.
Fixes: 1b98450816 ("Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole"
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
__btrfs_close_devices() would call_rcu to free the device, which is racy with
list_for_each_entry() accessing the memory to retrieve the next device on the
list.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The INO_LOOKUP ioctl can lookup path for a given inode number and is
thus restricted. As a sideefect it can find the root id of the
containing subvolume and we're using this int the 'btrfs inspect rootid'
command.
The restriction is unnecessary in case we set the ioctl args
args::treeid = 0
args::objectid = 256 (BTRFS_FIRST_FREE_OBJECTID)
Then the path will be empty and the treeid is filled with the root id of
the inode on which the ioctl is called. This behaviour is unchanged,
after the root restriction is removed.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Report missing device when add is successful,
otherwise it would exit as ENOMEM. And add uuid
to the report.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Old csum type check is wrong and can't catch csum_type 1(not supported).
Fix it to avoid hostile 0 division.
Reported-by: Lukas Lueg <lukas.lueg@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Marc reported a problem where the receiving end of an incremental send
was performing clone operations that failed with -EINVAL. This happened
because, unlike for uncompressed extents, we were not checking if the
source clone offset and length, after summing the data offset, falls
within the source file's boundaries.
So make sure we do such checks when attempting to issue clone operations
for compressed extents.
Problem reproducible with the following steps:
$ mkfs.btrfs -f /dev/sdb
$ mount -o compress /dev/sdb /mnt
$ mkfs.btrfs -f /dev/sdc
$ mount -o compress /dev/sdc /mnt2
# Create the file with a single extent of 128K. This creates a metadata file
# extent item with a data start offset of 0 and a logical length of 128K.
$ xfs_io -f -c "pwrite -S 0xaa 64K 128K" -c "fsync" /mnt/foo
# Now rewrite the range 64K to 112K of our file. This will make the inode's
# metadata continue to point to the 128K extent we created before, but now
# with an extent item that points to the extent with a data start offset of
# 112K and a logical length of 16K.
# That metadata file extent item is associated with the logical file offset
# at 176K and covers the logical file range 176K to 192K.
$ xfs_io -c "pwrite -S 0xbb 64K 112K" -c "fsync" /mnt/foo
# Now rewrite the range 180K to 12K. This will make the inode's metadata
# continue to point the the 128K extent we created earlier, with a single
# extent item that points to it with a start offset of 112K and a logical
# length of 4K.
# That metadata file extent item is associated with the logical file offset
# at 176K and covers the logical file range 176K to 180K.
$ xfs_io -c "pwrite -S 0xcc 180K 12K" -c "fsync" /mnt/foo
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ touch /mnt/bar
# Calls the btrfs clone ioctl.
$ ~/xfstests/src/cloner -s $((176 * 1024)) -d $((176 * 1024)) \
-l $((4 * 1024)) /mnt/foo /mnt/bar
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs send /mnt/snap1 | btrfs receive /mnt2
At subvol /mnt/snap1
At subvol snap1
$ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
At subvol /mnt/snap2
At snapshot snap2
ERROR: failed to clone extents to bar
Invalid argument
A test case for fstests follows soon.
Reported-by: Marc MERLIN <marc@merlins.org>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Tested-by: David Sterba <dsterba@suse.cz>
Tested-by: Jan Alexander Steffens (heftig) <jan.steffens@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit 9c8b35b1ba ("btrfs: quota: Automatically update related qgroups or
mark INCONSISTENT flags when assigning/deleting a qgroup relations.")
introduced the allocation of a temporary ulist in function
btrfs_add_qgroup_relation() and added the corresponding cleanup to the out
path. However, the allocation was introduced before the src/dst level check
that directly returns. Fix the possible leakage of the ulist by moving the
allocation after the input validation. Detected by Coverity CID 1295988.
Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
If the call to btrfs_truncate_inode_items() failed and we don't have a block
group, we were unlocking the cache_write_mutex without having locked it (we
do it only if we have a block group).
Fixes: 1bbc621ef2 ("Btrfs: allow block group cache writeout
outside critical section in commit")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
fs/btrfs/volumes.c: In function ‘btrfs_create_uuid_tree’:
fs/btrfs/volumes.c:3909:3: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘long int’ [-Wformat=]
btrfs_abort_transaction(trans, tree_root,
^
CC [M] fs/btrfs/ioctl.o
fs/btrfs/ioctl.c: In function ‘create_subvol’:
fs/btrfs/ioctl.c:549:3: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘long int’ [-Wformat=]
btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
PTR_ERR returns long, but we're really using 'int' for the error codes
everywhere so just set and use the local variable.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The annotated functios will be placed into .text.unlikely section. The
annotation also hints compiler to move the code out of the hot paths,
and may implicitly mark if-statement leading to that block as unlikely.
This is a heuristic, the impact on the generated code is not
significant.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
WARN is called from a single location and all bugreports say that's in
super.c __btrfs_abort_transaction. This is slightly confusing as we'd
rather want to know the exact callsite. Whereas this information is
printed in the syslog below the stacktrace, this requires further look
and we usually see only the headline from WARNING.
Moving the WARN into the macro has to inline some code and increases
code by a few kilobytes:
text data bss dec hex filename
835481 20305 14120 869906 d4612 btrfs.ko.before
842883 20305 14120 877308 d62fc btrfs.ko.after
The delta is +7k (130+ calls), measured on 3.19 x86_64, distro config.
The increase is not small and could lead to worse icache use. The code
is on error/exit paths that can be recognized by compiler as cold and
moved out of the way so the impact is speculated to be low, if
measurable at all.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Long time ago (2008) the defrag was automatic for new b-tree writes but
has been disabled after performance problems. There was a leftover in
tree-defrag.c that effectively stops any defragmentation on b-trees.
This is a bit unexpected and IMHO undesired. The SSD mode is an
optimization and defrag is supposed to work if the users asks for it.
Related commits:
6702ed490c
Btrfs: Add run time btree defrag, and an ioctl to force btree defrag
e18e4809b1
Btrfs: Add mount -o ssd, which includes optimizations for seek free
storage
b3236e68bf
Btrfs: Leave on the tree defragger in mount -o ssd, it still helps there
9afbb0b752
Btrfs: Disable tree defrag in SSD mode
The last three commits switch the defrag+ssd off/on/off and the last one
3f157a2fd2
Btrfs: Online btree defragmentation fixes
misses the bits from tree-defrag.c to revert to the behaviour introduced
in e18e4809b1.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
When we shrink the usable size of a device (its total_bytes), we go over
all the device extent items in the device tree and attempt to relocate
the chunk of any device extent that goes beyond the new usable size for
the device. We do that after setting the new usable size (total_bytes) in
the device object, so that all new allocations (and reallocations) don't
use areas of the device that go beyond the new (shorter) size. However we
were not considering that before setting the new size in the device,
pending chunks might have been created that use device extents that go
beyond the new size, and those device extents are not yet in the device
tree after we search the device tree - they are still attached to the
list of new block group for some ongoing transaction handle, and they are
only added to the device tree when the transaction handle is ended (via
btrfs_create_pending_block_groups()).
So check for pending chunks with device extents that go beyond the new
size and if any exists, commit the current transaction and repeat the
search in the device tree.
Not doing this it would mean we would return success to user space while
still having extents that go beyond the new size, and later user space
could override those locations on the device while the fs still references
them, causing all sorts of corruption and unexpected events.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Since commit bafc9b754f ("vfs: More precise tests in d_invalidate"),
mounted subvolumes can be deleted because d_invalidate() won't fail.
However, we run into problems when we attempt to delete the default
subvolume while it is mounted as the root filesystem:
# btrfs subvol list /
ID 257 gen 306 top level 5 path rootvol
ID 267 gen 334 top level 5 path snap1
# btrfs subvol get-default /
ID 267 gen 334 top level 5 path snap1
# btrfs inspect-internal rootid /
267
# mount -o subvol=/ /dev/vda1 /mnt
# btrfs subvol del /mnt/snap1
Delete subvolume (no-commit): '/mnt/snap1'
ERROR: cannot delete '/mnt/snap1' - Operation not permitted
# findmnt /
findmnt: can't read /proc/mounts: No such file or directory
# ls /proc
#
Markus reported that this same scenario simply led to a kernel oops.
This happens because in btrfs_ioctl_snap_destroy(), we call
d_invalidate() before we check may_destroy_subvol(), which means that we
detach the submounts and drop the dentry before erroring out. Instead,
we should only invalidate the dentry once the deletion has succeeded.
Additionally, the shrink_dcache_sb() isn't necessary; d_invalidate()
will prune the dcache for the deleted subvolume.
Cc: <stable@vger.kernel.org>
Fixes: bafc9b754f ("vfs: More precise tests in d_invalidate")
Reported-by: Markus Schauler <mschauler@gmail.com>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
If a directory inode is orphanized, because some inode previously
processed has a new name that collides with the old name of the current
inode, we need to check if it needs its rename operation delayed too,
as its ancestor-descendent relationship with some other inode might
have been reversed between the parent and send snapshots and therefore
its rename operation needs to happen after that other inode is renamed.
For example, for the following reproducer where this is needed (provided
by Robbie Ko):
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt2
$ mkdir -p /mnt/data/n1/n2
$ mkdir /mnt/data/n4
$ mkdir -p /mnt/data/t6/t7
$ mkdir /mnt/data/t5
$ mkdir /mnt/data/t7
$ mkdir /mnt/data/n4/t2
$ mkdir /mnt/data/t4
$ mkdir /mnt/data/t3
$ mv /mnt/data/t7 /mnt/data/n4/t2
$ mv /mnt/data/t4 /mnt/data/n4/t2/t7
$ mv /mnt/data/t5 /mnt/data/n4/t2/t7/t4
$ mv /mnt/data/t6 /mnt/data/n4/t2/t7/t4/t5
$ mv /mnt/data/n1/n2 /mnt/data/n4/t2/t7/t4/t5/t6
$ mv /mnt/data/n1 /mnt/data/n4/t2/t7/t4/t5/t6
$ mv /mnt/data/n4/t2/t7/t4/t5/t6/t7 /mnt/data/n4/t2/t7/t4/t5/t6/n2
$ mv /mnt/data/t3 /mnt/data/n4/t2/t7/t4/t5/t6/n2/t7
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ mv /mnt/data/n4/t2/t7/t4/t5/t6/n1 /mnt/data/n4
$ mv /mnt/data/n4/t2 /mnt/data/n4/n1
$ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6/n2 /mnt/data/n4/n1/t2
$ mv /mnt/data/n4/n1/t2/n2/t7/t3 /mnt/data/n4/n1/t2
$ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6 /mnt/data/n4/n1/t2
$ mv /mnt/data/n4/n1/t2/t7/t4 /mnt/data/n4/n1/t2/t6
$ mv /mnt/data/n4/n1/t2/t7 /mnt/data/n4/n1/t2/t3
$ mv /mnt/data/n4/n1/t2/n2/t7 /mnt/data/n4/n1/t2
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs send /mnt/snap1 | btrfs receive /mnt2
$ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
ERROR: send ioctl failed with -12: Cannot allocate memory
Where the parent snapshot directory hierarchy is the following:
. (ino 256)
|-- data/ (ino 257)
|-- n4/ (ino 260)
|-- t2/ (ino 265)
|-- t7/ (ino 264)
|-- t4/ (ino 266)
|-- t5/ (ino 263)
|-- t6/ (ino 261)
|-- n1/ (ino 258)
|-- n2/ (ino 259)
|-- t7/ (ino 262)
|-- t3/ (ino 267)
And the send snapshot's directory hierarchy is the following:
. (ino 256)
|-- data/ (ino 257)
|-- n4/ (ino 260)
|-- n1/ (ino 258)
|-- t2/ (ino 265)
|-- n2/ (ino 259)
|-- t3/ (ino 267)
| |-- t7 (ino 264)
|
|-- t6/ (ino 261)
| |-- t4/ (ino 266)
| |-- t5/ (ino 263)
|
|-- t7/ (ino 262)
While processing inode 262 we orphanize inode 264 and later attempt
to rename inode 264 to its new name/location, which resulted in building
an incorrect destination path string for the rename operation with the
value "data/n4/t2/t7/t4/t5/t6/n2/t7/t3/t7". This rename operation must
have been done only after inode 267 is processed and renamed, as the
ancestor-descendent relationship between inodes 264 and 267 was reversed
between both snapshots, because otherwise it results in an infinite loop
when building the path string for inode 264 when we are processing an
inode with a number larger than 264. That loop is the following:
start inode 264, send progress of 265 for example
parent of 264 -> 267
parent of 267 -> 262
parent of 262 -> 259
parent of 259 -> 261
parent of 261 -> 263
parent of 263 -> 266
parent of 266 -> 264
|--> back to first iteration while current path string length
is <= PATH_MAX, and fail with -ENOMEM otherwise
So fix this by making the check if we need to delay a directory rename
regardless of the current inode having been orphanized or not.
A test case for fstests follows soon.
Thanks to Robbie Ko for providing a reproducer for this problem.
Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Even though we delay the rename of directories when they become
descendents of other directories that were also renamed in the send
root to prevent infinite path build loops, we were doing it in cases
where this was not needed and was actually harmful resulting in
infinite path build loops as we ended up with a circular dependency
of delayed directory renames.
Consider the following reproducer:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt2
$ mkdir /mnt/data
$ mkdir /mnt/data/n1
$ mkdir /mnt/data/n1/n2
$ mkdir /mnt/data/n4
$ mkdir /mnt/data/n1/n2/p1
$ mkdir /mnt/data/n1/n2/p1/p2
$ mkdir /mnt/data/t6
$ mkdir /mnt/data/t7
$ mkdir -p /mnt/data/t5/t7
$ mkdir /mnt/data/t2
$ mkdir /mnt/data/t4
$ mkdir -p /mnt/data/t1/t3
$ mkdir /mnt/data/p1
$ mv /mnt/data/t1 /mnt/data/p1
$ mkdir -p /mnt/data/p1/p2
$ mv /mnt/data/t4 /mnt/data/p1/p2/t1
$ mv /mnt/data/t5 /mnt/data/n4/t5
$ mv /mnt/data/n1/n2/p1/p2 /mnt/data/n4/t5/p2
$ mv /mnt/data/t7 /mnt/data/n4/t5/p2/t7
$ mv /mnt/data/t2 /mnt/data/n4/t1
$ mv /mnt/data/p1 /mnt/data/n4/t5/p2/p1
$ mv /mnt/data/n1/n2 /mnt/data/n4/t5/p2/p1/p2/n2
$ mv /mnt/data/n4/t5/p2/p1/p2/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1
$ mv /mnt/data/n4/t5/t7 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7
$ mv /mnt/data/n4/t5/p2/p1/t1/t3 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3
$ mv /mnt/data/n4/t5/p2/p1/p2/n2/p1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1
$ mv /mnt/data/t6 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3/t5
$ mv /mnt/data/n4/t5/p2/p1/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3/t1
$ mv /mnt/data/n1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1/n1
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ mv /mnt/data/n4/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1/t1
$ mv /mnt/data/n4/t5/p2/p1/p2/n2/t1 /mnt/data/n4/
$ mv /mnt/data/n4/t5/p2/p1/p2/n2 /mnt/data/n4/t1/n2
$ mv /mnt/data/n4/t1/t7/p1 /mnt/data/n4/t1/n2/p1
$ mv /mnt/data/n4/t1/t3/t1 /mnt/data/n4/t1/n2/t1
$ mv /mnt/data/n4/t1/t3 /mnt/data/n4/t1/n2/t1/t3
$ mv /mnt/data/n4/t5/p2/p1/p2 /mnt/data/n4/t1/n2/p1/p2
$ mv /mnt/data/n4/t1/t7 /mnt/data/n4/t1/n2/p1/t7
$ mv /mnt/data/n4/t5/p2/p1 /mnt/data/n4/t1/n2/p1/p2/p1
$ mv /mnt/data/n4/t1/n2/t1/t3/t5 /mnt/data/n4/t1/n2/p1/p2/t5
$ mv /mnt/data/n4/t5 /mnt/data/n4/t1/n2/p1/p2/p1/t5
$ mv /mnt/data/n4/t1/n2/p1/p2/p1/t5/p2 /mnt/data/n4/t1/n2/p1/p2/p1/p2
$ mv /mnt/data/n4/t1/n2/p1/p2/p1/p2/t7 /mnt/data/n4/t1/t7
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs send /mnt/snap1 | btrfs receive /mnt2
$ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive -vv /mnt2
ERROR: send ioctl failed with -12: Cannot allocate memory
This reproducer resulted in an infinite path build loop when building the
path for inode 266 because the following circular dependency of delayed
directory renames was created:
ino 272 <- ino 261 <- ino 259 <- ino 268 <- ino 267 <- ino 261
Where the notation "X <- Y" means the rename of inode X is delayed by the
rename of inode Y (X will be renamed after Y is renamed). This resulted
in an infinite path build loop of inode 266 because that inode has inode
261 as an ancestor in the send root and inode 261 is in the circular
dependency of delayed renames listed above.
Fix this by not delaying the rename of a directory inode if an ancestor of
the inode in the send root, which has a delayed rename operation, is not
also a descendent of the inode in the parent root.
Thanks to Robbie Ko for sending the reproducer example.
A test case for xfstests follows soon.
Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
To support seed sysfs layout and represent seed fsid under
the sprout we need the facility to create fsid under the
specified parent.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs_kobj_add_device() does not need fs_info any more.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Just a helper function to clean up the sysfs fsid kobjects.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
This patch will provide a framework and help to create attributes
from the structure btrfs_fs_devices which are available even before
fs_info is created. So by moving the parent kobject super_kobj from
fs_info to btrfs_fs_devices, it will help to create attributes
from the btrfs_fs_devices as well.
Patches on top of this patch now will be able to create the
sys/fs/btrfs/fsid kobject and attributes from btrfs_fs_devices
when devices are scanned and registered to the kernel.
Just to note, this does not change any of the existing btrfs sysfs
external kobject names and its attributes and not even the life
cycle of them. Changes are internal only. And to ensure the same,
this path has been tested with various device operations and,
checking and comparing the sysfs kobjects and attributes with
sysfs kobject and attributes with out this patch, and they remain
same.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Separate device kobject and its attribute creation so that device
kobject can be created from the device discovery thread.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
As of now btrfs_attrs are provided using the default_attrs through
the kset. Separate them and create the default_attrs using the
sysfs_create_files instead. By doing this we will have the
flexibility that device discovery thread could create fsid
kobject.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
We need it in a seperate function so that it can be called from the
device discovery thread as well.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
As of now the order in which the kobjects are created
at btrfs_sysfs_add_one() is..
fsid
features
unknown features (dynamic features)
devices.
Since we would move fsid and device kobject to fs_devices
from fs_info structure, this patch will reorder in which
the kobjects are created as below.
fsid
devices
features
unknown features (dynamic features)
And hence the btrfs_sysfs_remove_one() will follow the same
in reverse order. and the device kobject destroy now can
be moved into the function __btrfs_sysfs_remove_one()
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Since the failure code in the btrfs_sysfs_add_one() can
call btrfs_sysfs_remove_one() even before device_dir_kobj
has been created we need to check if its null.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
The sysfs clean up self test like in the below code fails, since
fs_info->device_dir_kobject still points to its stale kobject.
Reseting this pointer will help to fix this.
open_ctree()
{
ret = btrfs_sysfs_add_one(fs_info);
::
+ btrfs_sysfs_remove_one(fs_info);
+ ret = btrfs_sysfs_add_one(fs_info);
+ if (ret) {
+ pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
+ goto fail_block_groups;
+ }
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Theoritically need to remove the device links attributes, but since its entire device
kobject was removed, so there wasn't any issue of about it. Just do it nicely.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
kobject_unregister is to handle the release of the kobject,
its completion init is being called in btrfs_sysfs_add_one(),
so we don't have to do the same in the open_ctree() again.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
The following test case fails indicating that, thread tried to init an initialized object.
kernel: [232104.016513] kobject (ffff880006c1c980): tried to init an initialized object, something is seriously wrong.
btrfs_sysfs_remove_one() self test code:
open_tree()
{
::
ret = btrfs_sysfs_add_one(fs_info);
if (ret) {
pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
goto fail_block_groups;
}
+ btrfs_sysfs_remove_one(fs_info);
+ ret = btrfs_sysfs_add_one(fs_info);
+ if (ret) {
+ pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
+ goto fail_block_groups;
+ }
cleaning up the unregistered kobject fixes this.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Pull btrfs fixes from Chris Mason:
"I fixed up a regression from 4.0 where conversion between different
raid levels would sometimes bail out without converting.
Filipe tracked down a race where it was possible to double allocate
chunks on the drive.
Mark has a fix for fiemap. All three will get bundled off for stable
as well"
* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix regression in raid level conversion
Btrfs: fix racy system chunk allocation when setting block group ro
btrfs: clear 'ret' in btrfs_check_shared() loop
Commit c4cf5261 ("bio: skip atomic inc/dec of ->bi_remaining for
non-chains") regressed all existing callers that followed this pattern:
1) saving a bio's original bi_end_io
2) wiring up an intermediate bi_end_io
3) restoring the original bi_end_io from intermediate bi_end_io
4) calling bio_endio() to execute the restored original bi_end_io
The regression was due to BIO_CHAIN only ever getting set if
bio_inc_remaining() is called. For the above pattern it isn't set until
step 3 above (step 2 would've needed to establish BIO_CHAIN). As such
the first bio_endio(), in step 2 above, never decremented __bi_remaining
before calling the intermediate bi_end_io -- leaving __bi_remaining with
the value 1 instead of 0. When bio_inc_remaining() occurred during step
3 it brought it to a value of 2. When the second bio_endio() was
called, in step 4 above, it should've called the original bi_end_io but
it didn't because there was an extra reference that wasn't dropped (due
to atomic operations being optimized away since BIO_CHAIN wasn't set
upfront).
Fix this issue by removing the __bi_remaining management complexity for
all callers that use the above pattern -- bio_chain() is the only
interface that _needs_ to be concerned with __bi_remaining. For the
above pattern callers just expect the bi_end_io they set to get called!
Remove bio_endio_nodec() and also remove all bio_inc_remaining() calls
that aren't associated with the bio_chain() interface.
Also, the bio_inc_remaining() interface has been moved local to bio.c.
Fixes: c4cf5261 ("bio: skip atomic inc/dec of ->bi_remaining for non-chains")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit 2f0810880f changed
btrfs_set_block_group_ro to avoid trying to allocate new chunks with the
new raid profile during conversion. This fixed failures when there was
no space on the drive to allocate a new chunk, but the metadata
reserves were sufficient to continue the conversion.
But this ended up causing a regression when the drive had plenty of
space to allocate new chunks, mostly because reduce_alloc_profile isn't
using the new raid profile.
Fixing btrfs_reduce_alloc_profile is a bigger patch. For now, do a
partial revert of 2f0810880, and don't error out if we hit ENOSPC.
Signed-off-by: Chris Mason <clm@fb.com>
Tested-by: Dave Sterba <dsterba@suse.cz>
Reported-by: Holger Hoffstaette <holger.hoffstaette@googlemail.com>
If while setting a block group read-only we end up allocating a system
chunk, through check_system_chunk(), we were not doing it while holding
the chunk mutex which is a problem if a concurrent chunk allocation is
happening, through do_chunk_alloc(), as it means both block groups can
end up using the same logical addresses and physical regions in the
device(s). So make sure we hold the chunk mutex.
Cc: stable@vger.kernel.org # 4.0+
Fixes: 2f0810880f ("btrfs: delete chunk allocation attemp when
setting block group ro")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_check_shared() is leaking a return value of '1' from
find_parent_nodes(). As a result, callers (in this case, extent_fiemap())
are told extents are shared when they are not. This in turn broke fiemap on
btrfs for kernels v3.18 and up.
The fix is simple - we just have to clear 'ret' after we are done processing
the results of find_parent_nodes().
It wasn't clear to me at first what was happening with return values in
btrfs_check_shared() and find_parent_nodes() - thanks to Josef for the help
on irc. I added documentation to both functions to make things more clear
for the next hacker who might come across them.
If we could queue this up for -stable too that would be great.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Since the big barrier rewrite/removal in 2007 we never fail FLUSH or
FUA requests, which means we can remove the magic BIO_EOPNOTSUPP flag
to help propagating those to the buffer_head layer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull btrfs fixes from Chris Mason:
"The first commit is a fix from Filipe for a very old extent buffer
reuse race that triggered a BUG_ON. It hasn't come up often, I looked
through old logs at FB and we hit it a handful of times over the last
year.
The rest are other corners he hit during testing"
* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix race when reusing stale extent buffers that leads to BUG_ON
Btrfs: fix race between block group creation and their cache writeout
Btrfs: fix panic when starting bg cache writeout after IO error
Btrfs: fix crash after inode cache writeback failure
There's a race between releasing extent buffers that are flagged as stale
and recycling them that makes us it the following BUG_ON at
btrfs_release_extent_buffer_page:
BUG_ON(extent_buffer_under_io(eb))
The BUG_ON is triggered because the extent buffer has the flag
EXTENT_BUFFER_DIRTY set as a consequence of having been reused and made
dirty by another concurrent task.
Here follows a sequence of steps that leads to the BUG_ON.
CPU 0 CPU 1 CPU 2
path->nodes[0] == eb X
X->refs == 2 (1 for the tree, 1 for the path)
btrfs_header_generation(X) == current trans id
flag EXTENT_BUFFER_DIRTY set on X
btrfs_release_path(path)
unlocks X
reads eb X
X->refs incremented to 3
locks eb X
btrfs_del_items(X)
X becomes empty
clean_tree_block(X)
clear EXTENT_BUFFER_DIRTY from X
btrfs_del_leaf(X)
unlocks X
extent_buffer_get(X)
X->refs incremented to 4
btrfs_free_tree_block(X)
X's range is not pinned
X's range added to free
space cache
free_extent_buffer_stale(X)
lock X->refs_lock
set EXTENT_BUFFER_STALE on X
release_extent_buffer(X)
X->refs decremented to 3
unlocks X->refs_lock
btrfs_release_path()
unlocks X
free_extent_buffer(X)
X->refs becomes 2
__btrfs_cow_block(Y)
btrfs_alloc_tree_block()
btrfs_reserve_extent()
find_free_extent()
gets offset == X->start
btrfs_init_new_buffer(X->start)
btrfs_find_create_tree_block(X->start)
alloc_extent_buffer(X->start)
find_extent_buffer(X->start)
finds eb X in radix tree
free_extent_buffer(X)
lock X->refs_lock
test X->refs == 2
test bit EXTENT_BUFFER_STALE is set
test !extent_buffer_under_io(eb)
increments X->refs to 3
mark_extent_buffer_accessed(X)
check_buffer_tree_ref(X)
--> does nothing,
X->refs >= 2 and
EXTENT_BUFFER_TREE_REF
is set in X
clear EXTENT_BUFFER_STALE from X
locks X
btrfs_mark_buffer_dirty()
set_extent_buffer_dirty(X)
check_buffer_tree_ref(X)
--> does nothing, X->refs >= 2 and
EXTENT_BUFFER_TREE_REF is set
sets EXTENT_BUFFER_DIRTY on X
test and clear EXTENT_BUFFER_TREE_REF
decrements X->refs to 2
release_extent_buffer(X)
decrements X->refs to 1
unlock X->refs_lock
unlock X
free_extent_buffer(X)
lock X->refs_lock
release_extent_buffer(X)
decrements X->refs to 0
btrfs_release_extent_buffer_page(X)
BUG_ON(extent_buffer_under_io(X))
--> EXTENT_BUFFER_DIRTY set on X
Fix this by making find_extent buffer wait for any ongoing task currently
executing free_extent_buffer()/free_extent_buffer_stale() if the extent
buffer has the stale flag set.
A more clean alternative would be to always increment the extent buffer's
reference count while holding its refs_lock spinlock but find_extent_buffer
is a performance critical area and that would cause lock contention whenever
multiple tasks search for the same extent buffer concurrently.
A build server running a SLES 12 kernel (3.12 kernel + over 450 upstream
btrfs patches backported from newer kernels) was hitting this often:
[1212302.461948] kernel BUG at ../fs/btrfs/extent_io.c:4507!
(...)
[1212302.470219] CPU: 1 PID: 19259 Comm: bs_sched Not tainted 3.12.36-38-default #1
[1212302.540792] Hardware name: Supermicro PDSM4/PDSM4, BIOS 6.00 04/17/2006
[1212302.540792] task: ffff8800e07e0100 ti: ffff8800d6412000 task.ti: ffff8800d6412000
[1212302.540792] RIP: 0010:[<ffffffffa0507081>] [<ffffffffa0507081>] btrfs_release_extent_buffer_page.constprop.51+0x101/0x110 [btrfs]
(...)
[1212302.630008] Call Trace:
[1212302.630008] [<ffffffffa05070cd>] release_extent_buffer+0x3d/0xa0 [btrfs]
[1212302.630008] [<ffffffffa04c2d9d>] btrfs_release_path+0x1d/0xa0 [btrfs]
[1212302.630008] [<ffffffffa04c5c7e>] read_block_for_search.isra.33+0x13e/0x3a0 [btrfs]
[1212302.630008] [<ffffffffa04c8094>] btrfs_search_slot+0x3f4/0xa80 [btrfs]
[1212302.630008] [<ffffffffa04cf5d8>] lookup_inline_extent_backref+0xf8/0x630 [btrfs]
[1212302.630008] [<ffffffffa04d13dd>] __btrfs_free_extent+0x11d/0xc40 [btrfs]
[1212302.630008] [<ffffffffa04d64a4>] __btrfs_run_delayed_refs+0x394/0x11d0 [btrfs]
[1212302.630008] [<ffffffffa04db379>] btrfs_run_delayed_refs.part.66+0x69/0x280 [btrfs]
[1212302.630008] [<ffffffffa04ed2ad>] __btrfs_end_transaction+0x2ad/0x3d0 [btrfs]
[1212302.630008] [<ffffffffa04f7505>] btrfs_evict_inode+0x4a5/0x500 [btrfs]
[1212302.630008] [<ffffffff811b9e28>] evict+0xa8/0x190
[1212302.630008] [<ffffffff811b0330>] do_unlinkat+0x1a0/0x2b0
I was also able to reproduce this on a 3.19 kernel, corresponding to Chris'
integration branch from about a month ago, running the following stress
test on a qemu/kvm guest (with 4 virtual cpus and 16Gb of ram):
while true; do
mkfs.btrfs -l 4096 -f -b `expr 20 \* 1024 \* 1024 \* 1024` /dev/sdd
mount /dev/sdd /mnt
snapshot_cmd="btrfs subvolume snapshot -r /mnt"
snapshot_cmd="$snapshot_cmd /mnt/snap_\`date +'%H_%M_%S_%N'\`"
fsstress -d /mnt -n 25000 -p 8 -x "$snapshot_cmd" -X 100
umount /mnt
done
Which usually triggers the BUG_ON within less than 24 hours:
[49558.618097] ------------[ cut here ]------------
[49558.619732] kernel BUG at fs/btrfs/extent_io.c:4551!
(...)
[49558.620031] CPU: 3 PID: 23908 Comm: fsstress Tainted: G W 3.19.0-btrfs-next-7+ #3
[49558.620031] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[49558.620031] task: ffff8800319fc0d0 ti: ffff880220da8000 task.ti: ffff880220da8000
[49558.620031] RIP: 0010:[<ffffffffa0476b1a>] [<ffffffffa0476b1a>] btrfs_release_extent_buffer_page+0x20/0xe9 [btrfs]
(...)
[49558.620031] Call Trace:
[49558.620031] [<ffffffffa0476c73>] release_extent_buffer+0x90/0xd3 [btrfs]
[49558.620031] [<ffffffff8142b10c>] ? _raw_spin_lock+0x3b/0x43
[49558.620031] [<ffffffffa0477052>] ? free_extent_buffer+0x37/0x94 [btrfs]
[49558.620031] [<ffffffffa04770ab>] free_extent_buffer+0x90/0x94 [btrfs]
[49558.620031] [<ffffffffa04396d5>] btrfs_release_path+0x4a/0x69 [btrfs]
[49558.620031] [<ffffffffa0444907>] __btrfs_free_extent+0x778/0x80c [btrfs]
[49558.620031] [<ffffffffa044a485>] __btrfs_run_delayed_refs+0xad2/0xc62 [btrfs]
[49558.728054] [<ffffffff811420d5>] ? kmemleak_alloc_recursive.constprop.52+0x16/0x18
[49558.728054] [<ffffffffa044c1e8>] btrfs_run_delayed_refs+0x6d/0x1ba [btrfs]
[49558.728054] [<ffffffffa045917f>] ? join_transaction.isra.9+0xb9/0x36b [btrfs]
[49558.728054] [<ffffffffa045a75c>] btrfs_commit_transaction+0x4c/0x981 [btrfs]
[49558.728054] [<ffffffffa0434f86>] btrfs_sync_fs+0xd5/0x10d [btrfs]
[49558.728054] [<ffffffff81155923>] ? iterate_supers+0x60/0xc4
[49558.728054] [<ffffffff8117966a>] ? do_sync_work+0x91/0x91
[49558.728054] [<ffffffff8117968a>] sync_fs_one_sb+0x20/0x22
[49558.728054] [<ffffffff81155939>] iterate_supers+0x76/0xc4
[49558.728054] [<ffffffff811798e8>] sys_sync+0x55/0x83
[49558.728054] [<ffffffff8142bbd2>] system_call_fastpath+0x12/0x17
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
So creating a block group has 2 distinct phases:
Phase 1 - creates the btrfs_block_group_cache item and adds it to the
rbtree fs_info->block_group_cache_tree and to the corresponding list
space_info->block_groups[];
Phase 2 - adds the block group item to the extent tree and corresponding
items to the chunk tree.
The first phase adds the block_group_cache_item to a list of pending block
groups in the transaction handle, and phase 2 happens when
btrfs_end_transaction() is called against the transaction handle.
It happens that once phase 1 completes, other concurrent tasks that use
their own transaction handle, but points to the same running transaction
(struct btrfs_trans_handle->transaction), can use this block group for
space allocations and therefore mark it dirty. Dirty block groups are
tracked in a list belonging to the currently running transaction (struct
btrfs_transaction) and not in the transaction handle (btrfs_trans_handle).
This is a problem because once a task calls btrfs_commit_transaction(),
it calls btrfs_start_dirty_block_groups() which will see all dirty block
groups and attempt to start their writeout, including those that are
still attached to the transaction handle of some concurrent task that
hasn't called btrfs_end_transaction() yet - which means those block
groups haven't gone through phase 2 yet and therefore when
write_one_cache_group() is called, it won't find the block group items
in the extent tree and abort the current transaction with -ENOENT,
turning the fs into readonly mode and require a remount.
Fix this by ignoring -ENOENT when looking for block group items in the
extent tree when we attempt to start the writeout of the block group
caches outside the critical section of the transaction commit. We will
try again later during the critical section and if there we still don't
find the block group item in the extent tree, we then abort the current
transaction.
This issue happened twice, once while running fstests btrfs/067 and once
for btrfs/078, which produced the following trace:
[ 3278.703014] WARNING: CPU: 7 PID: 18499 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x114 [btrfs]()
[ 3278.707329] BTRFS: Transaction aborted (error -2)
(...)
[ 3278.731555] Call Trace:
[ 3278.732396] [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[ 3278.733860] [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[ 3278.735312] [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[ 3278.736874] [<ffffffffa03ada6d>] ? __btrfs_abort_transaction+0x52/0x114 [btrfs]
[ 3278.738302] [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[ 3278.739520] [<ffffffffa03ada6d>] __btrfs_abort_transaction+0x52/0x114 [btrfs]
[ 3278.741222] [<ffffffffa03b9e56>] write_one_cache_group+0xae/0xbf [btrfs]
[ 3278.742797] [<ffffffffa03c487b>] btrfs_start_dirty_block_groups+0x170/0x2b2 [btrfs]
[ 3278.744492] [<ffffffffa03d309c>] btrfs_commit_transaction+0x130/0x9c9 [btrfs]
[ 3278.746084] [<ffffffff8107d33d>] ? trace_hardirqs_on+0xd/0xf
[ 3278.747249] [<ffffffffa03e5660>] btrfs_sync_file+0x313/0x387 [btrfs]
[ 3278.748744] [<ffffffff8117acad>] vfs_fsync_range+0x95/0xa4
[ 3278.749958] [<ffffffff81435b54>] ? ret_from_sys_call+0x1d/0x58
[ 3278.751218] [<ffffffff8117acd8>] vfs_fsync+0x1c/0x1e
[ 3278.754197] [<ffffffff8117ae54>] do_fsync+0x34/0x4e
[ 3278.755192] [<ffffffff8117b07c>] SyS_fsync+0x10/0x14
[ 3278.756236] [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[ 3278.757366] ---[ end trace 9a4d4df4969709aa ]---
Fixes: 1bbc621ef2 ("Btrfs: allow block group cache writeout
outside critical section in commit")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When waiting for the writeback of block group cache we returned
immediately if there was an error during writeback without waiting
for the ordered extent to complete. This left a short time window
where if some other task attempts to start the writeout for the same
block group cache it can attempt to add a new ordered extent, starting
at the same offset (0) before the previous one is removed from the
ordered tree, causing an ordered tree panic (calls BUG()).
This normally doesn't happen in other write paths, such as buffered
writes or direct IO writes for regular files, since before marking
page ranges dirty we lock the ranges and wait for any ordered extents
within the range to complete first.
Fix this by making btrfs_wait_ordered_range() not return immediately
if it gets an error from the writeback, waiting for all ordered extents
to complete first.
This issue happened often when running the fstest btrfs/088 and it's
easy to trigger it by running in a loop until the panic happens:
for ((i = 1; i <= 10000; i++)) do ./check btrfs/088 ; done
[17156.862573] BTRFS critical (device sdc): panic in ordered_data_tree_panic:70: Inconsistency in ordered tree at offset 0 (errno=-17 Object already exists)
[17156.864052] ------------[ cut here ]------------
[17156.864052] kernel BUG at fs/btrfs/ordered-data.c:70!
(...)
[17156.864052] Call Trace:
[17156.864052] [<ffffffffa03876e3>] btrfs_add_ordered_extent+0x12/0x14 [btrfs]
[17156.864052] [<ffffffffa03787e2>] run_delalloc_nocow+0x5bf/0x747 [btrfs]
[17156.864052] [<ffffffffa03789ff>] run_delalloc_range+0x95/0x353 [btrfs]
[17156.864052] [<ffffffffa038b7fe>] writepage_delalloc.isra.16+0xb9/0x13f [btrfs]
[17156.864052] [<ffffffffa038d75b>] __extent_writepage+0x129/0x1f7 [btrfs]
[17156.864052] [<ffffffffa038da5a>] extent_write_cache_pages.isra.15.constprop.28+0x231/0x2f4 [btrfs]
[17156.864052] [<ffffffff810ad2af>] ? __module_text_address+0x12/0x59
[17156.864052] [<ffffffff8107d33d>] ? trace_hardirqs_on+0xd/0xf
[17156.864052] [<ffffffffa038df76>] extent_writepages+0x4b/0x5c [btrfs]
[17156.864052] [<ffffffff81144431>] ? kmem_cache_free+0x9b/0xce
[17156.864052] [<ffffffffa0376a46>] ? btrfs_submit_direct+0x3fc/0x3fc [btrfs]
[17156.864052] [<ffffffffa0389cd6>] ? free_extent_state+0x8c/0xc1 [btrfs]
[17156.864052] [<ffffffffa0374871>] btrfs_writepages+0x28/0x2a [btrfs]
[17156.864052] [<ffffffff8110c4c8>] do_writepages+0x23/0x2c
[17156.864052] [<ffffffff81102f36>] __filemap_fdatawrite_range+0x5a/0x61
[17156.864052] [<ffffffff81102f6e>] filemap_fdatawrite_range+0x13/0x15
[17156.864052] [<ffffffffa0383ef7>] btrfs_fdatawrite_range+0x21/0x48 [btrfs]
[17156.864052] [<ffffffffa03ab89e>] __btrfs_write_out_cache.isra.14+0x2d9/0x3a7 [btrfs]
[17156.864052] [<ffffffffa03ac1ab>] ? btrfs_write_out_cache+0x41/0xdc [btrfs]
[17156.864052] [<ffffffffa03ac1fd>] btrfs_write_out_cache+0x93/0xdc [btrfs]
[17156.864052] [<ffffffffa0363847>] ? btrfs_start_dirty_block_groups+0x13a/0x2b2 [btrfs]
[17156.864052] [<ffffffffa03638e6>] btrfs_start_dirty_block_groups+0x1d9/0x2b2 [btrfs]
[17156.864052] [<ffffffff8107d33d>] ? trace_hardirqs_on+0xd/0xf
[17156.864052] [<ffffffffa037209e>] btrfs_commit_transaction+0x130/0x9c9 [btrfs]
[17156.864052] [<ffffffffa034c748>] btrfs_sync_fs+0xe1/0x12d [btrfs]
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If the writeback of an inode cache failed we were unnecessarilly
attempting to release again the delalloc metadata that we previously
reserved. However attempting to do this a second time triggers an
assertion at drop_outstanding_extent() because we have no more
outstanding extents for our inode cache's inode. If we were able
to start writeback of the cache the reserved metadata space is
released at btrfs_finished_ordered_io(), even if an error happens
during writeback.
So make sure we don't repeat the metadata space release if writeback
started for our inode cache.
This issue was trivial to reproduce by running the fstest btrfs/088
with "-o inode_cache", which triggered the assertion leading to a
BUG() call and requiring a reboot in order to run the remaining
fstests. Trace produced by btrfs/088:
[255289.385904] BTRFS: assertion failed: BTRFS_I(inode)->outstanding_extents >= num_extents, file: fs/btrfs/extent-tree.c, line: 5276
[255289.388094] ------------[ cut here ]------------
[255289.389184] kernel BUG at fs/btrfs/ctree.h:4057!
[255289.390125] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
(...)
[255289.392068] Call Trace:
[255289.392068] [<ffffffffa035e774>] drop_outstanding_extent+0x3d/0x6d [btrfs]
[255289.392068] [<ffffffffa0364988>] btrfs_delalloc_release_metadata+0x54/0xe3 [btrfs]
[255289.392068] [<ffffffffa03b4174>] btrfs_write_out_ino_cache+0x95/0xad [btrfs]
[255289.392068] [<ffffffffa036f5c4>] btrfs_save_ino_cache+0x275/0x2dc [btrfs]
[255289.392068] [<ffffffffa03e2d83>] commit_fs_roots.isra.12+0xaa/0x137 [btrfs]
[255289.392068] [<ffffffff8107d33d>] ? trace_hardirqs_on+0xd/0xf
[255289.392068] [<ffffffffa037841f>] ? btrfs_commit_transaction+0x4b1/0x9c9 [btrfs]
[255289.392068] [<ffffffff814351a4>] ? _raw_spin_unlock+0x32/0x46
[255289.392068] [<ffffffffa037842e>] btrfs_commit_transaction+0x4c0/0x9c9 [btrfs]
(...)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fix from Chris Mason:
"When an arm user reported crashes near page_address(page) in my new
code, it became clear that I can't be trusted with GFP masks. Filipe
beat me to the patch, and I'll just be in the corner with my dunce cap
on"
* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix wrong mapping flags for free space inode
We were passing a flags value that differed from the intention in commit
2b10826800 ("Btrfs: don't use highmem for free space cache pages").
This caused problems in a ARM machine, leaving btrfs unusable there.
Reported-by: Merlijn Wajer <merlijn@wizzup.org>
Tested-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Struct bio has a reference count that controls when it can be freed.
Most uses cases is allocating the bio, which then returns with a
single reference to it, doing IO, and then dropping that single
reference. We can remove this atomic_dec_and_test() in the completion
path, if nobody else is holding a reference to the bio.
If someone does call bio_get() on the bio, then we flag the bio as
now having valid count and that we must properly honor the reference
count when it's being put.
Tested-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull btrfs fixes from Chris Mason:
"A few more btrfs fixes.
These range from corners Filipe found in the new free space cache
writeback to a grab bag of fixes from the list"
* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: btrfs_release_extent_buffer_page didn't free pages of dummy extent
Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.
btrfs: unlock i_mutex after attempting to delete subvolume during send
btrfs: check io_ctl_prepare_pages return in __btrfs_write_out_cache
btrfs: fix race on ENOMEM in alloc_extent_buffer
btrfs: handle ENOMEM in btrfs_alloc_tree_block
Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole
Btrfs: don't check for delalloc_bytes in cache_save_setup
Btrfs: fix deadlock when starting writeback of bg caches
Btrfs: fix race between start dirty bg cache writeout and bg deletion
btrfs_release_extent_buffer_page() can't handle dummy extent that
allocated by btrfs_clone_extent_buffer() properly. That is because
reference count of pages that allocated by btrfs_clone_extent_buffer()
was 2, 1 by alloc_page(), and another by attach_extent_buffer_page().
Running following command repeatly can check this memory leak problem
btrfs inspect-internal inode-resolve 256 /mnt/btrfs
Signed-off-by: Chien-Kuan Yeh <ckya@synology.com>
Signed-off-by: Forrest Liu <forrestl@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"Filipe hit two problems in my block group cache patches. We finalized
the fixes last week and ran through more tests"
* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: prevent list corruption during free space cache processing
Btrfs: fix inode cache writeout
Pull fourth vfs update from Al Viro:
"d_inode() annotations from David Howells (sat in for-next since before
the beginning of merge window) + four assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
RCU pathwalk breakage when running into a symlink overmounting something
fix I_DIO_WAKEUP definition
direct-io: only inc/dec inode->i_dio_count for file systems
fs/9p: fix readdir()
VFS: assorted d_backing_inode() annotations
VFS: fs/inode.c helpers: d_inode() annotations
VFS: fs/cachefiles: d_backing_inode() annotations
VFS: fs library helpers: d_inode() annotations
VFS: assorted weird filesystems: d_inode() annotations
VFS: normal filesystems (and lustre): d_inode() annotations
VFS: security/: d_inode() annotations
VFS: security/: d_backing_inode() annotations
VFS: net/: d_inode() annotations
VFS: net/unix: d_backing_inode() annotations
VFS: kernel/: d_inode() annotations
VFS: audit: d_backing_inode() annotations
VFS: Fix up some ->d_inode accesses in the chelsio driver
VFS: Cachefiles should perform fs modifications on the top layer only
VFS: AF_UNIX sockets should call mknod on the top layer only
We need to fill inode when we found a node for it in delayed_nodes_tree.
But we did not fill the ->last_trans currently, it will cause the test
of xfstest/generic/311 fail. Scenario of the 311 is shown as below:
Problem:
(1). test_fd = open(fname, O_RDWR|O_DIRECT)
(2). pwrite(test_fd, buf, 4096, 0)
(3). close(test_fd)
(4). drop_all_caches() <-------- "echo 3 > /proc/sys/vm/drop_caches"
(5). test_fd = open(fname, O_RDWR|O_DIRECT)
(6). fsync(test_fd);
<-------- we did not get the correct log entry for the file
Reason:
When we re-open this file in (5), we would find a node
in delayed_nodes_tree and fill the inode we are lookup with the
information. But the ->last_trans is not filled, then the fsync()
will check the ->last_trans and found it's 0 then say this inode
is already in our tree which is commited, not recording the extents
for it.
Fix:
This patch fill the ->last_trans properly and set the
runtime_flags if needed in this situation. Then we can get the
log entries we expected after (6) and generic/311 passed.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>
Whenever the check for a send in progress introduced in commit
521e0546c9 (btrfs: protect snapshots from deleting during send) is
hit, we return without unlocking inode->i_mutex. This is easy to see
with lockdep enabled:
[ +0.000059] ================================================
[ +0.000028] [ BUG: lock held when returning to user space! ]
[ +0.000029] 4.0.0-rc5-00096-g3c435c1 #93 Not tainted
[ +0.000026] ------------------------------------------------
[ +0.000029] btrfs/211 is leaving the kernel with locks still held!
[ +0.000029] 1 lock held by btrfs/211:
[ +0.000023] #0: (&type->i_mutex_dir_key){+.+.+.}, at: [<ffffffff8135b8df>] btrfs_ioctl_snap_destroy+0x2df/0x7a0
Make sure we unlock it in the error path.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
If io_ctl_prepare_pages fails, the pages in io_ctl.pages are not valid.
When we try to access them later, things will blow up in various ways.
Also fix the comment about the return value, which is an errno on error,
not -1, and update the cases where it was not.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
Consider the following interleaving of overlapping calls to
alloc_extent_buffer:
Call 1:
- Successfully allocates a few pages with find_or_create_page
- find_or_create_page fails, goto free_eb
- Unlocks the allocated pages
Call 2:
- Calls find_or_create_page and gets a page in call 1's extent_buffer
- Finds that the page is already associated with an extent_buffer
- Grabs a reference to the half-written extent_buffer and calls
mark_extent_buffer_accessed on it
mark_extent_buffer_accessed will then try to call mark_page_accessed on
a null page and panic.
The fix is to decrement the reference count on the half-written
extent_buffer before unlocking the pages so call 2 won't use it. We
should also set exists = NULL in the case that we don't use exists to
avoid accidentally returning a freed extent_buffer in an error case.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
This is one of the first places to give out when memory is tight. Handle
it properly rather than with a BUG_ON.
Also fix the comment about the return value, which is an ERR_PTR, not
NULL, on error.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
If device tree has hole, find_free_dev_extent() cannot find available
address properly.
The problem can be reproduce by following script.
mntpath=/btrfs
loopdev=/dev/loop0
filepath=/home/forrest/image
umount $mntpath
losetup -d $loopdev
truncate --size 100g $filepath
losetup $loopdev $filepath
mkfs.btrfs -f $loopdev
mount $loopdev $mntpath
# make device tree with one big hole
for i in `seq 1 1 100`; do
fallocate -l 1g $mntpath/$i
done
sync
for i in `seq 1 1 95`; do
rm $mntpath/$i
done
sync
# wait cleaner thread remove unused block group
sleep 300
fallocate -l 1g $mntpath/aaa
# failed to allocate new chunk
fallocate -l 1g $mntpath/bbb
Above script will make device tree with one big hole, and can only allocate
just one chunk in a transaction, so failed to allocate new chunk for $mntpath/bbb
item 8 key (1 DEV_EXTENT 2185232384) itemoff 15859 itemsize 48
dev extent chunk_tree 3
chunk objectid 256 chunk offset 106292051968 length 1073741824
item 9 key (1 DEV_EXTENT 104190705664) itemoff 15811 itemsize 48
dev extent chunk_tree 3
chunk objectid 256 chunk offset 103108575232 length 1073741824
Signed-off-by: Forrest Liu <forrestl@synology.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Now that we're doing free space cache writeback outside the critical
section in the commit, there is a bigger window for delalloc_bytes to
be added after a cache has been written. find_free_extent may do this
without putting the block group back into the dirty list, and also
without a transaction running.
Checking for delalloc_bytes in cache_save_setup means we might leave the
cache marked as written without invalidating it. Consistency checks
during mount will toss the cache, but it's better to get rid of the
check in cache_save_setup and let it get invalidated by the checks
already done during cache write out.
Signed-off-by: Chris Mason <clm@fb.com>
While running xfstests I ran into the following:
[20892.242791] ------------[ cut here ]------------
[20892.243776] WARNING: CPU: 0 PID: 13299 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x114 [btrfs]()
[20892.245874] BTRFS: Transaction aborted (error -2)
[20892.247329] Modules linked in: btrfs dm_snapshot dm_bufio dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse$
[20892.258488] CPU: 0 PID: 13299 Comm: fsstress Tainted: G W 4.0.0-rc5-btrfs-next-9+ #2
[20892.262011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[20892.264738] 0000000000000009 ffff880427f8bc18 ffffffff8142fa46 ffffffff8108b6a2
[20892.266244] ffff880427f8bc68 ffff880427f8bc58 ffffffff81045ea5 ffff880427f8bc48
[20892.267761] ffffffffa0509a6d 00000000fffffffe ffff8803545d6f40 ffffffffa05a15a0
[20892.269378] Call Trace:
[20892.269915] [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[20892.271097] [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[20892.272173] [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[20892.273386] [<ffffffffa0509a6d>] ? __btrfs_abort_transaction+0x52/0x114 [btrfs]
[20892.274857] [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[20892.275851] [<ffffffffa0509a6d>] __btrfs_abort_transaction+0x52/0x114 [btrfs]
[20892.277341] [<ffffffffa0515e10>] write_one_cache_group+0x68/0xaf [btrfs]
[20892.278628] [<ffffffffa052088a>] btrfs_start_dirty_block_groups+0x18d/0x29b [btrfs]
[20892.280191] [<ffffffffa052f077>] btrfs_commit_transaction+0x130/0x9c9 [btrfs]
[20892.281781] [<ffffffff8107d33d>] ? trace_hardirqs_on+0xd/0xf
[20892.282873] [<ffffffffa054163b>] btrfs_sync_file+0x313/0x387 [btrfs]
[20892.284111] [<ffffffff8117acad>] vfs_fsync_range+0x95/0xa4
[20892.285203] [<ffffffff810e603f>] ? time_hardirqs_on+0x15/0x28
[20892.286290] [<ffffffff8123960b>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[20892.287469] [<ffffffff8117acd8>] vfs_fsync+0x1c/0x1e
[20892.288412] [<ffffffff8117ae54>] do_fsync+0x34/0x4e
[20892.289348] [<ffffffff8117b07c>] SyS_fsync+0x10/0x14
[20892.290255] [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[20892.291316] ---[ end trace 597f77e664245373 ]---
[20892.293955] BTRFS: error (device sdg) in write_one_cache_group:3184: errno=-2 No such entry
[20892.297390] BTRFS info (device sdg): forced readonly
This happens because in btrfs_start_dirty_block_groups() we splice the
transaction's list of dirty block groups into a local list and then we
keep extracting the first element of the list without holding the
cache_write_mutex mutex. This means that before we acquire that mutex
the first block group on the list might be removed by a conurrent task
running btrfs_remove_block_group(). So make sure we extract the first
element (and test the list emptyness) while holding that mutex.
Fixes: 1bbc621ef2 ("Btrfs: allow block group cache writeout
outside critical section in commit")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
do_blockdev_direct_IO() increments and decrements the inode
->i_dio_count for each IO operation. It does this to protect against
truncate of a file. Block devices don't need this sort of protection.
For a capable multiqueue setup, this atomic int is the only shared
state between applications accessing the device for O_DIRECT, and it
presents a scaling wall for that. In my testing, as much as 30% of
system time is spent incrementing and decrementing this value. A mixed
read/write workload improved from ~2.5M IOPS to ~9.6M IOPS, with
better latencies too. Before:
clat percentiles (usec):
| 1.00th=[ 33], 5.00th=[ 34], 10.00th=[ 34], 20.00th=[ 34],
| 30.00th=[ 34], 40.00th=[ 34], 50.00th=[ 35], 60.00th=[ 35],
| 70.00th=[ 35], 80.00th=[ 35], 90.00th=[ 37], 95.00th=[ 80],
| 99.00th=[ 98], 99.50th=[ 151], 99.90th=[ 155], 99.95th=[ 155],
| 99.99th=[ 165]
After:
clat percentiles (usec):
| 1.00th=[ 95], 5.00th=[ 108], 10.00th=[ 129], 20.00th=[ 149],
| 30.00th=[ 155], 40.00th=[ 161], 50.00th=[ 167], 60.00th=[ 171],
| 70.00th=[ 177], 80.00th=[ 185], 90.00th=[ 201], 95.00th=[ 270],
| 99.00th=[ 390], 99.50th=[ 398], 99.90th=[ 418], 99.95th=[ 422],
| 99.99th=[ 438]
In other setups, Robert Elliott reported seeing good performance
improvements:
https://lkml.org/lkml/2015/4/3/557
The more applications accessing the device, the worse it gets.
Add a new direct-io flags, DIO_SKIP_DIO_COUNT, which tells
do_blockdev_direct_IO() that it need not worry about incrementing
or decrementing the inode i_dio_count for this caller.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Elliott, Robert (Server Storage) <elliott@hp.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
__btrfs_write_out_cache is holding the ctl->tree_lock while it prepares
a list of bitmaps to record in the free space cache. It was dropping
the lock while it worked on other components, which made a window for
free_bitmap() to free the bitmap struct without removing it from the
list.
This changes things to hold the lock the whole time, and also makes sure
we hold the lock during enospc cleanup.
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs updates from Chris Mason:
"I've been running these through a longer set of load tests because my
commits change the free space cache writeout. It fixes commit stalls
on large filesystems (~20T space used and up) that we have been
triggering here. We were seeing new writers blocked for 10 seconds or
more during commits, which is far from good.
Josef and I fixed up ENOSPC aborts when deleting huge files (3T or
more), that are triggered because our metadata reservations were not
properly accounting for crcs and were not replenishing during the
truncate.
Also in this series, a number of qgroup fixes from Fujitsu and Dave
Sterba collected most of the pending cleanups from the list"
* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (93 commits)
btrfs: quota: Update quota tree after qgroup relationship change.
btrfs: quota: Automatically update related qgroups or mark INCONSISTENT flags when assigning/deleting a qgroup relations.
btrfs: qgroup: clear STATUS_FLAG_ON in disabling quota.
btrfs: Update btrfs qgroup status item when rescan is done.
btrfs: qgroup: Fix dead judgement on qgroup_rescan_leaf() return value.
btrfs: Don't allow subvolid >= (1 << BTRFS_QGROUP_LEVEL_SHIFT) to be created
btrfs: Check qgroup level in kernel qgroup assign.
btrfs: qgroup: allow to remove qgroup which has parent but no child.
btrfs: qgroup: return EINVAL if level of parent is not higher than child's.
btrfs: qgroup: do a reservation in a higher level.
Btrfs: qgroup, Account data space in more proper timings.
Btrfs: qgroup: Introduce a may_use to account space_info->bytes_may_use.
Btrfs: qgroup: free reserved in exceeding quota.
Btrfs: qgroup: cleanup, remove an unsued parameter in btrfs_create_qgroup().
btrfs: qgroup: fix limit args override whole limit struct
btrfs: qgroup: update limit info in function btrfs_run_qgroups().
btrfs: qgroup: consolidate the parameter of fucntion update_qgroup_limit_item().
btrfs: qgroup: update qgroup in memory at the same time when we update it in btree.
btrfs: qgroup: inherit limit info from srcgroup in creating snapshot.
btrfs: Support busy loop of write and delete
...
The code to fix stalls during free spache cache IO wasn't using
the correct root when waiting on the IO for inode caches. This
is only a problem when the inode cache is enabled with
mount -o inode_cache
This fixes the inode cache writeout to preserve any error values and
makes sure not to override the root when inode cache writeout is done.
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Previous patch modified the in memory struct but it's not written in
quota tree until next commit.
So user will still get old data using "btrfs qgroup show" after
assign/remove.
This patch will call btrfs_run_qgroups in assign ioctl so it will be
updated to in memory quota trees and user will get up-to-date results.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Operation like qgroups assigning/deleting qgroup relations will mostly
cause qgroup data inconsistent, since it needs to do the full rescan to
determine whether shared extents are exclusive or still shared in
parent qgroups.
But there are some exceptions, like qgroup with only exclusive extents
(qgroup->excl == qgroup->rfer), in that case, we only needs to
modify all its parents' excl and rfer.
So this patch adds a quick path for such qgroup in qgroup
assign/remove routine, and if quick path failed, the qgroup status will
be marked INCONSISTENT, and return 1 to info user-land.
BTW since the quick path is much the same of qgroup_excl_accounting(),
so move the core of it to __qgroup_excl_accounting() and reuse it.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
we forgot to clear STATUS_FLAG_ON in quota_disable(), it
will cause a problem shown as below:
# mount /dev/sdc /mnt
# btrfs quota enable /mnt
# btrfs quota disable /mnt
# btrfs quota rescan /mnt
quota rescan started <--- expecting it fail here.
# echo $?
0
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Update qgroup status when rescan is done.
Before this patch, status item is not updated on rescan finish, which
causing the RESCAN and INCONSISTENT flags never cleared.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Old qgroup_rescan_leaf() comment indicates ret == 2 as complete and
cleared INCONSISTENT flag.
This is not true since it will never return 2, and inside it no codes
will clear INCONSISTENT flag.
The flag clearance is done in btrfs_qgroup_rescan_work().
This caused the bug that INCONSISTENT flag is never cleared.
So change the comment and fix the dead judgment.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Btrfs will create qgroup on subvolume creation if quota is enabled, but
qgroup uses the high bits(currently 16 bits) as level, to build the
inheritance.
However it is fully possible a subvolume can be created with a
subvolumeid larger than 1 << BTRFS_QGROUP_LEVEL_SHIFT, so it will be
considered as level 1 and can't be assigned to other qgroup in level 1.
This patch will prevent such things so qgroup inheritance will not be
screwed up.
The downside is very clear, btrfs subvolume number limit will decrease
from (u64 max - 256(fisrt free objectid) - 256(last free objectid)) to
(u48 max -256(first free objectid)).
But we still have near u48(that's 15 digits in dec), so that should not
be a huge problem.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Although we have qgroup level check in btrfs-progs, it's not enough
since other programe may still call ioctl directly not using
btrfs-progs. For example, systemd.
But it's btrfs-progs to be blame since we don't provide a
full-function(like subvolume create things) btrfs library with enough
check, and only rely on kernel ioctl.
So Add level checks in kernel too.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
When a qgroup has parents but no child, it should be removable in
Theory I think. But currently, we can not remove it when it has
either parent or child.
Example:
# btrfs quota enable /mnt
# btrfs qgroup create 1/0 /mnt
# btrfs qgroup create 2/0 /mnt
# btrfs qgroup assign 1/0 2/0 /mnt
# btrfs qgroup show -pcre /mnt
qgroupid rfer excl max_rfer max_excl parent child
-------- ---- ---- -------- -------- ------ -----
0/5 16384 16384 0 0 --- ---
1/0 0 0 0 0 2/0 ---
2/0 0 0 0 0 --- 1/0
At this time, there is no subvol or qgroup depending on it.
Just a qgroup 2/0 is its parent, but 2/0 can work well without
1/0. So I think 1/0 should be removalbe. But:
# btrfs qgroup destroy 1/0 /mnt
ERROR: unable to destroy quota group: Device or resource busy
This patch remove the check of qgroup->parent in removing it,
then we can remove a qgroup when it has a parent.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we create a subvol inheriting a qgroup, we need to check the level
of them. Otherwise, there is a chance a qgroup can inherit another qgroup
at the same level.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
There are two problems in qgroup:
a). The PAGE_CACHE is 4K, even when we are writing a data of 1K,
qgroup will reserve a 4K size. It will cause the last 3K in a qgroup
is not available to user.
b). When user is writing a inline data, qgroup will not reserve it,
it means this is a window we can exceed the limit of a qgroup.
The main idea of this patch is reserving the data size of write_bytes
rather than the reserve_bytes. It means qgroup will not care about
the data size btrfs will reserve for user, but only care about the
data size user is going to write. Then reserve it when user want to
write and release it in transaction committed.
In this way, qgroup can be released from the complex procedure in
btrfs and only do the reserve when user want to write and account
when the data is written in commit_transaction().
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currenly, in data writing, ->reserved is accounted in
fill_delalloc(), but ->may_use is released in clear_bit_hook()
which is called by btrfs_finish_ordered_io(). That's too late,
that said, between fill_delalloc() and btrfs_finish_ordered_io(),
the data is doublely accounted by qgroup. It will cause some
unexpected -EDQUOT.
Example:
# btrfs quota enable /root/btrfs-auto-test/
# btrfs subvolume create /root/btrfs-auto-test//sub
Create subvolume '/root/btrfs-auto-test/sub'
# btrfs qgroup limit 1G /root/btrfs-auto-test//sub
dd if=/dev/zero of=/root/btrfs-auto-test//sub/file bs=1024 count=1500000
dd: error writing '/root/btrfs-auto-test//sub/file': Disk quota exceeded
681353+0 records in
681352+0 records out
697704448 bytes (698 MB) copied, 8.15563 s, 85.5 MB/s
It's (698 MB) when we got an -EDQUOT, but we limit it by 1G.
This patch move the btrfs_qgroup_reserve/free() for data from
btrfs_delalloc_reserve/release_metadata() to btrfs_check_data_free_space()
and btrfs_free_reserved_data_space(). Then the accounter in qgroup
will be updated at the same time with the accounter in space_info updated.
In this way, the unexpected -EDQUOT will be killed.
Reported-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently, for pre_alloc or delay_alloc, the bytes will be accounted
in space_info by the three guys.
space_info->bytes_may_use --- space_info->reserved --- space_info->used.
But on the other hand, in qgroup, there are only two counters to account the
bytes, qgroup->reserved and qgroup->excl. And qg->reserved accounts
bytes in space_info->bytes_may_use and qg->excl accounts bytes in
space_info->used. So the bytes in space_info->reserved is not accounted
in qgroup. If so, there is a window we can exceed the quota limit when
bytes is in space_info->reserved.
Example:
# btrfs quota enable /mnt
# btrfs qgroup limit -e 10M /mnt
# for((i=0;i<20;i++));do fallocate -l 1M /mnt/data$i; done
# sync
# btrfs qgroup show -pcre /mnt
qgroupid rfer excl max_rfer max_excl parent child
-------- ---- ---- -------- -------- ------ -----
0/5 20987904 20987904 0 10485760 --- ---
qg->excl is 20987904 larger than max_excl 10485760.
This patch introduce a new counter named may_use to qgroup, then
there are three counters in qgroup to account bytes in space_info
as below.
space_info->bytes_may_use --- space_info->reserved --- space_info->used.
qgroup->may_use --- qgroup->reserved --- qgroup->excl
With this patch applied:
# btrfs quota enable /mnt
# btrfs qgroup limit -e 10M /mnt
# for((i=0;i<20;i++));do fallocate -l 1M /mnt/data$i; done
fallocate: /mnt/data9: fallocate failed: Disk quota exceeded
fallocate: /mnt/data10: fallocate failed: Disk quota exceeded
fallocate: /mnt/data11: fallocate failed: Disk quota exceeded
fallocate: /mnt/data12: fallocate failed: Disk quota exceeded
fallocate: /mnt/data13: fallocate failed: Disk quota exceeded
fallocate: /mnt/data14: fallocate failed: Disk quota exceeded
fallocate: /mnt/data15: fallocate failed: Disk quota exceeded
fallocate: /mnt/data16: fallocate failed: Disk quota exceeded
fallocate: /mnt/data17: fallocate failed: Disk quota exceeded
fallocate: /mnt/data18: fallocate failed: Disk quota exceeded
fallocate: /mnt/data19: fallocate failed: Disk quota exceeded
# sync
# btrfs qgroup show -pcre /mnt
qgroupid rfer excl max_rfer max_excl parent child
-------- ---- ---- -------- -------- ------ -----
0/5 9453568 9453568 0 10485760 --- ---
Reported-by: Cyril SCETBON <cyril.scetbon@free.fr>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we exceed quota limit in writing, we will free
some reserved extent when we need to drop but not free
account in qgroup. It means, each time we exceed quota
in writing, there will be some remain space in qg->reserved
we can not use any more. If things go on like this, the
all space will be ate up.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_limit_group use arg limit to override the old qgroup_limit of
corresponding qgroup. However, we should override part of old qgroup_limit
according to the bit which has been set in arg limit.
Signed-off-by: Fan Chengniang <fancn.fnst@cn.fujitsu.com>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we commit_transaction(), qgroups in btree should be updated.
But, limit info is not considered currently. It will cause a problem
when a qgroup of a snapshot inherit the limit info from srcqgroup,
then there is an inconsistency.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Cleanup: Change the parameter of update_qgroup_limit_item() to the family of
update_qgroup_xxx_item().
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we call btrfs_qgroup_inherit() with BTRFS_QGROUP_INHERIT_SET_LIMITS,
btrfs will update the limit info of qgroup in btree but forget to update
the qgroup in rbtree at the same time. It obviousely will cause an inconsistency.
This patch fix it by updating the rbtree at the same time.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently, when we snapshot a subvol, snapshot will not copy the limits
from srcqgroup.
This patch make the qgroup in snapshot inherit the limit info when create
a snapshot.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Reproduce:
while true; do
dd if=/dev/zero of=/mnt/btrfs/file count=[75% fs_size]
rm /mnt/btrfs/file
done
Then we can see above loop failed on NO_SPACE.
It it long-term problem since very beginning, because delayed-iput
after rm are not run.
We already have commit_transaction() in alloc_space code, but it is
not triggered in above case.
This patch trigger commit_transaction() to run delayed-iput and
reflash pinned-space to to make write success.
It is based on previous fix of delayed-iput in commit_transaction(),
need to be applied on top of:
btrfs: Fix NO_SPACE bug caused by delayed-iput
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Steps to reproduce:
while true; do
dd if=/dev/zero of=/btrfs_dir/file count=[fs_size * 75%]
rm /btrfs_dir/file
sync
done
And we'll see dd failed because btrfs return NO_SPACE.
Reason:
Normally, btrfs_commit_transaction() call btrfs_run_delayed_iputs()
in end to free fs space for next write, but sometimes it hadn't
done work on time, because btrfs-cleaner thread get delayed-iputs
from list before, but do iput() after next write.
This is log:
[ 2569.050776] comm=btrfs-cleaner func=btrfs_evict_inode() begin
[ 2569.084280] comm=sync func=btrfs_commit_transaction() call btrfs_run_delayed_iputs()
[ 2569.085418] comm=sync func=btrfs_commit_transaction() done btrfs_run_delayed_iputs()
[ 2569.087554] comm=sync func=btrfs_commit_transaction() end
[ 2569.191081] comm=dd begin
[ 2569.790112] comm=dd func=__btrfs_buffered_write() ret=-28
[ 2569.847479] comm=btrfs-cleaner func=add_pinned_bytes() 0 + 32677888 = 32677888
[ 2569.849530] comm=btrfs-cleaner func=add_pinned_bytes() 32677888 + 23834624 = 56512512
...
[ 2569.903893] comm=btrfs-cleaner func=add_pinned_bytes() 943976448 + 21762048 = 965738496
[ 2569.908270] comm=btrfs-cleaner func=btrfs_evict_inode() end
Fix:
Make btrfs_commit_transaction() wait current running btrfs-cleaner's
delayed-iputs() done in end.
Test:
Use script similar to above(more complex),
before patch:
7 failed in 100 * 20 loop.
after patch:
0 failed in 100 * 20 loop.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
space_info's value calculation is some complex and easy to cause
bug, add WARN_ON() to help debug.
Changelog v1->v2:
Put WARN_ON()s under the ENOSPC_DEBUG mount option.
Suggested by: David Sterba <dsterba@suse.cz>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Bug1:
space_info->bytes_readonly was set to very large(negative) value in
btrfs_remove_block_group().
Reason:
Current code set block_group_cache->pinned = 0 in btrfs_delete_unused_bgs(),
but above space was not counted to space_info->bytes_readonly.
Then in btrfs_remove_block_group():
block_group->space_info->bytes_readonly -= block_group->key.offset;
We can see following value in trace:
btrfs_remove_block_group: pid=2677 comm=btrfs-cleaner WARNING: bytes_readonly=12582912, key.offset=134217728
Bug2:
space_info->total_bytes_pinned grow to value larger than fs size.
In a 1.2G fs, we can get following trace log:
at first:
ZL_DEBUG: add_pinned_bytes: pid=2710 comm=sync change total_bytes_pinned flags=1 869793792 + 95944704 = 965738496
after some op:
ZL_DEBUG: add_pinned_bytes: pid=2770 comm=sync change total_bytes_pinned flags=1 1780178944 + 95944704 = 1876123648
after some op:
ZL_DEBUG: add_pinned_bytes: pid=3193 comm=sync change total_bytes_pinned flags=1 2924568576 + 95551488 = 3020120064
...
Reason:
Similar to bug1, we also need to adjust space_info->total_bytes_pinned
in above code block.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we have any chance to make a successful write, we should not give up.
This patch adjust commit-transaction condition from:
pinned >= wanted
to
left + pinned >= wanted
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
It is another reason for NO_SPACE case.
When we found enough free space in loop and saved them to
max_hole_start/size before, and tail space contains pending extent,
origional innocent max_hole_start/size are reset in retry.
As a result, find_free_dev_extent() returns less space than it can,
and cause NO_SPACE in user program.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Old code bypass commit transaction when we don't have enough
pinned space, but another case is there exist freed bgs in current
transction, it have possibility to make alloc_chunk success.
This patch modify the condition to:
if (have_free_bg || have_pinned_space) commit_transaction()
Confirmed above action by printk before and after patch.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit 0d97a64e0 creates a new variable but doesn't always set it up.
This puts it back to the original method (key.offset + 1) for the cases
not covered by Filipe's new logic.
Signed-off-by: Chris Mason <clm@fb.com>
If we attempt to clone a 0 length region into a file we can end up
inserting a range in the inode's extent_io tree with a start offset
that is greater then the end offset, which triggers immediately the
following warning:
[ 3914.619057] WARNING: CPU: 17 PID: 4199 at fs/btrfs/extent_io.c:435 insert_state+0x4b/0x10b [btrfs]()
[ 3914.620886] BTRFS: end < start 4095 4096
(...)
[ 3914.638093] Call Trace:
[ 3914.638636] [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[ 3914.639620] [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[ 3914.640789] [<ffffffffa03ca44f>] ? insert_state+0x4b/0x10b [btrfs]
[ 3914.642041] [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48
[ 3914.643236] [<ffffffffa03ca44f>] insert_state+0x4b/0x10b [btrfs]
[ 3914.644441] [<ffffffffa03ca729>] __set_extent_bit+0x107/0x3f4 [btrfs]
[ 3914.645711] [<ffffffffa03cb256>] lock_extent_bits+0x65/0x1bf [btrfs]
[ 3914.646914] [<ffffffff8142b2fb>] ? _raw_spin_unlock+0x28/0x33
[ 3914.648058] [<ffffffffa03cbac4>] ? test_range_bit+0xcc/0xde [btrfs]
[ 3914.650105] [<ffffffffa03cb3c3>] lock_extent+0x13/0x15 [btrfs]
[ 3914.651361] [<ffffffffa03db39e>] lock_extent_range+0x3d/0xcd [btrfs]
[ 3914.652761] [<ffffffffa03de1fe>] btrfs_ioctl_clone+0x278/0x388 [btrfs]
[ 3914.654128] [<ffffffff811226dd>] ? might_fault+0x58/0xb5
[ 3914.655320] [<ffffffffa03e0909>] btrfs_ioctl+0xb51/0x2195 [btrfs]
(...)
[ 3914.669271] ---[ end trace 14843d3e2e622fc1 ]---
This later makes the inode eviction handler enter an infinite loop that
keeps dumping the following warning over and over:
[ 3915.117629] WARNING: CPU: 22 PID: 4228 at fs/btrfs/extent_io.c:435 insert_state+0x4b/0x10b [btrfs]()
[ 3915.119913] BTRFS: end < start 4095 4096
(...)
[ 3915.137394] Call Trace:
[ 3915.137913] [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[ 3915.139154] [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[ 3915.140316] [<ffffffffa03ca44f>] ? insert_state+0x4b/0x10b [btrfs]
[ 3915.141505] [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48
[ 3915.142709] [<ffffffffa03ca44f>] insert_state+0x4b/0x10b [btrfs]
[ 3915.143849] [<ffffffffa03ca729>] __set_extent_bit+0x107/0x3f4 [btrfs]
[ 3915.145120] [<ffffffffa038c1e3>] ? btrfs_kill_super+0x17/0x23 [btrfs]
[ 3915.146352] [<ffffffff811548f6>] ? deactivate_locked_super+0x3b/0x50
[ 3915.147565] [<ffffffffa03cb256>] lock_extent_bits+0x65/0x1bf [btrfs]
[ 3915.148785] [<ffffffff8142b7e2>] ? _raw_write_unlock+0x28/0x33
[ 3915.149931] [<ffffffffa03bc325>] btrfs_evict_inode+0x196/0x482 [btrfs]
[ 3915.151154] [<ffffffff81168904>] evict+0xa0/0x148
[ 3915.152094] [<ffffffff811689e5>] dispose_list+0x39/0x43
[ 3915.153081] [<ffffffff81169564>] evict_inodes+0xdc/0xeb
[ 3915.154062] [<ffffffff81154418>] generic_shutdown_super+0x49/0xef
[ 3915.155193] [<ffffffff811546d1>] kill_anon_super+0x13/0x1e
[ 3915.156274] [<ffffffffa038c1e3>] btrfs_kill_super+0x17/0x23 [btrfs]
(...)
[ 3915.167404] ---[ end trace 14843d3e2e622fc2 ]---
So just bail out of the clone ioctl if the length of the region to clone
is zero, without locking any extent range, in order to prevent this issue
(same behaviour as a pwrite with a 0 length for example).
This is trivial to reproduce. For example, the steps for the test I just
made for fstests:
mkfs.btrfs -f SCRATCH_DEV
mount SCRATCH_DEV $SCRATCH_MNT
touch $SCRATCH_MNT/foo
touch $SCRATCH_MNT/bar
$CLONER_PROG -s 0 -d 4096 -l 0 $SCRATCH_MNT/foo $SCRATCH_MNT/bar
umount $SCRATCH_MNT
A test case for fstests follows soon.
CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we pass a length of 0 to the extent_same ioctl, we end up locking an
extent range with a start offset greater then its end offset (if the
destination file's offset is greater than zero). This results in a warning
from extent_io.c:insert_state through the following call chain:
btrfs_extent_same()
btrfs_double_lock()
lock_extent_range()
lock_extent(inode->io_tree, offset, offset + len - 1)
lock_extent_bits()
__set_extent_bit()
insert_state()
--> WARN_ON(end < start)
This leads to an infinite loop when evicting the inode. This is the same
problem that my previous patch titled
"Btrfs: fix inode eviction infinite loop after cloning into it" addressed
but for the extent_same ioctl instead of the clone ioctl.
CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
While searching for extents to clone we might find one where we only use
a part of it coming from its tail. If our destination inode is the same
the source inode, we end up removing the tail part of the extent item and
insert after a new one that point to the same extent with an adjusted
key file offset and data offset. After this we search for the next extent
item in the fs/subvol tree with a key that has an offset incremented by
one. But this second search leaves us at the new extent item we inserted
previously, and since that extent item has a non-zero data offset, it
it can make us call btrfs_drop_extents with an empty range (start == end)
which causes the following warning:
[23978.537119] WARNING: CPU: 6 PID: 16251 at fs/btrfs/file.c:550 btrfs_drop_extent_cache+0x43/0x385 [btrfs]()
(...)
[23978.557266] Call Trace:
[23978.557978] [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[23978.559191] [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[23978.560699] [<ffffffffa047f0ea>] ? btrfs_drop_extent_cache+0x43/0x385 [btrfs]
[23978.562389] [<ffffffff8104544d>] warn_slowpath_null+0x1a/0x1c
[23978.563613] [<ffffffffa047f0ea>] btrfs_drop_extent_cache+0x43/0x385 [btrfs]
[23978.565103] [<ffffffff810e3a18>] ? time_hardirqs_off+0x15/0x28
[23978.566294] [<ffffffff81079ff8>] ? trace_hardirqs_off+0xd/0xf
[23978.567438] [<ffffffffa047f73d>] __btrfs_drop_extents+0x6b/0x9e1 [btrfs]
[23978.568702] [<ffffffff8107c03f>] ? trace_hardirqs_on+0xd/0xf
[23978.569763] [<ffffffff811441c0>] ? ____cache_alloc+0x69/0x2eb
[23978.570817] [<ffffffff81142269>] ? virt_to_head_page+0x9/0x36
[23978.571872] [<ffffffff81143c15>] ? cache_alloc_debugcheck_after.isra.42+0x16c/0x1cb
[23978.573466] [<ffffffff811420d5>] ? kmemleak_alloc_recursive.constprop.52+0x16/0x18
[23978.574962] [<ffffffffa0480d07>] btrfs_drop_extents+0x66/0x7f [btrfs]
[23978.576179] [<ffffffffa049aa35>] btrfs_clone+0x516/0xaf5 [btrfs]
[23978.577311] [<ffffffffa04983dc>] ? lock_extent_range+0x7b/0xcd [btrfs]
[23978.578520] [<ffffffffa049b2a2>] btrfs_ioctl_clone+0x28e/0x39f [btrfs]
[23978.580282] [<ffffffffa049d9ae>] btrfs_ioctl+0xb51/0x219a [btrfs]
(...)
[23978.591887] ---[ end trace 988ec2a653d03ed3 ]---
Then we attempt to insert a new extent item with a key that already
exists, which makes btrfs_insert_empty_item return -EEXIST resulting in
abortion of the current transaction:
[23978.594355] WARNING: CPU: 6 PID: 16251 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x114 [btrfs]()
(...)
[23978.622589] Call Trace:
[23978.623181] [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[23978.624359] [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[23978.625573] [<ffffffffa044ab6c>] ? __btrfs_abort_transaction+0x52/0x114 [btrfs]
[23978.626971] [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48
[23978.628003] [<ffffffff8108a6c8>] ? vprintk_default+0x1d/0x1f
[23978.629138] [<ffffffffa044ab6c>] __btrfs_abort_transaction+0x52/0x114 [btrfs]
[23978.630528] [<ffffffffa049ad1b>] btrfs_clone+0x7fc/0xaf5 [btrfs]
[23978.631635] [<ffffffffa04983dc>] ? lock_extent_range+0x7b/0xcd [btrfs]
[23978.632886] [<ffffffffa049b2a2>] btrfs_ioctl_clone+0x28e/0x39f [btrfs]
[23978.634119] [<ffffffffa049d9ae>] btrfs_ioctl+0xb51/0x219a [btrfs]
(...)
[23978.647714] ---[ end trace 988ec2a653d03ed4 ]---
This is wrong because we should not process the extent item that we just
inserted previously, and instead process the extent item that follows it
in the tree
For example for the test case I wrote for fstests:
bs=$((64 * 1024))
mkfs.btrfs -f -l $bs -O ^no-holes /dev/sdc
mount /dev/sdc /mnt
xfs_io -f -c "pwrite -S 0xaa $(($bs * 2)) $(($bs * 2))" /mnt/foo
$CLONER_PROG -s $((3 * $bs)) -d $((267 * $bs)) -l 0 /mnt/foo /mnt/foo
$CLONER_PROG -s $((217 * $bs)) -d $((95 * $bs)) -l 0 /mnt/foo /mnt/foo
The second clone call fails with -EEXIST, because when we process the
first extent item (offset 262144), we drop part of it (counting from the
end) and then insert a new extent item with a key greater then the key we
found. The next time we search the tree we search for a key with offset
262144 + 1, which leaves us at the new extent item we have just inserted
but we think it refers to an extent that we need to clone.
Fix this by ensuring the next search key uses an offset corresponding to
the offset of the key we found previously plus the data length of the
corresponding extent item. This ensures we skip new extent items that we
inserted and works for the case of implicit holes too (NO_HOLES feature).
A test case for fstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
... returning -E... upon error and amount of data left in iter after
(possible) truncation upon success. Note, that normal case gives
a non-zero (positive) return value, so any tests for != 0 _must_ be
updated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Conflicts:
fs/ext4/file.c
The rw parameter to direct_IO is redundant with iov_iter->type, and
treated slightly differently just about everywhere it's used: some users
do rw & WRITE, and others do rw == WRITE where they should be doing a
bitwise check. Simplify this with the new iov_iter_rw() helper, which
always returns either READ or WRITE.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Most filesystems call through to these at some point, so we'll start
here.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Near the end of close_ctree, we're calling btrfs_free_block_rsv
to free up the orphan rsv. The problem is this call updates the
space_info, which has already been freed.
This adds a new __ function that directly calls kfree instead of trying
to update the space infos.
Signed-off-by: Chris Mason <clm@fb.com>
We loop through all of the dirty block groups during commit and write
the free space cache. In order to make sure the cache is currect, we do
this while no other writers are allowed in the commit.
If a large number of block groups are dirty, this can introduce long
stalls during the final stages of the commit, which can block new procs
trying to change the filesystem.
This commit changes the block group cache writeout to take appropriate
locks and allow it to run earlier in the commit. We'll still have to
redo some of the block groups, but it means we can get most of the work
out of the way without blocking the entire FS.
Signed-off-by: Chris Mason <clm@fb.com>
In order to create the free space cache concurrently with FS modifications,
we need to take a few block group locks.
The cache code also does kmap, which would schedule with the locks held.
Instead of going through kmap_atomic, lets just use lowmem for the cache
pages.
Signed-off-by: Chris Mason <clm@fb.com>
Block group cache writeout is currently waiting on the pages for each
block group cache before moving on to writing the next one. This commit
switches things around to send down all the caches and then wait on them
in batches.
The end result is much faster, since we're keeping the disk pipeline
full.
Signed-off-by: Chris Mason <clm@fb.com>
We'll need to put the io_ctl into the block_group cache struct, so
name it struct btrfs_io_ctl and move it into ctree.h
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_evict_inode() needs to be more careful about stealing from the
global_rsv. We dont' want to end up aborting commit with ENOSPC just
because the evict_inode code was too greedy.
Signed-off-by: Chris Mason <clm@fb.com>
We're triggering a huge number of commits from
btrfs_async_reclaim_metadata_space. These aren't really requried,
because everyone calling the async reclaim code is going to end up
triggering a commit on their own.
Signed-off-by: Chris Mason <clm@fb.com>
When truncate starts, it allocates some space in the block reserves so
that we'll have enough to update metadata along the way.
For very large files, we can easily go through all of that space as we
loop through the extents. This changes truncate to refill the space
reservation as it progresses through the file.
Signed-off-by: Chris Mason <clm@fb.com>
As we delete large extents, we end up doing huge amounts of COW in order
to delete the corresponding crcs. This adds accounting so that we keep
track of that space and flushing of delayed refs so that we don't build
up too much delayed crc work.
This helps limit the delayed work that must be done at commit time and
tries to avoid ENOSPC aborts because the crcs eat all the global
reserves.
Signed-off-by: Chris Mason <clm@fb.com>
When we are deleting large files with large extents, we are building up
a huge set of delayed refs for processing. Truncate isn't checking
often enough to see if we need to back off and process those, or let
a commit proceed.
The end result is long stalls after the rm, and very long commit times.
During the commits, other processes back up waiting to start new
transactions and we get into trouble.
Signed-off-by: Chris Mason <clm@fb.com>
Building alpha:allmodconfig fails with
fs/btrfs/inode.c: In function 'check_direct_IO':
fs/btrfs/inode.c:8050:2: error: implicit declaration of function 'iov_iter_alignment'
due to a missing include file.
Fixes: 3737c63e1fb0 ("fs: move struct kiocb to fs.h")
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
This was used to make sure that a fresh btrfs from an older mkfs.btrfs,
but it also allows us to mount a buggy btrfs if this btrfs has the right
superblock head part but has something wrong with chunk tree part[1], and
after that we can hit BUG_ON()s set in the code to prevent something
impossible.
Since David has released "Btrfs progs v3.19-rc2", just remove the check,
if anyone who wants to make a fresh btrfs, please use the latest one.
[1]: http://www.spinics.net/lists/linux-btrfs/msg42358.html
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Omar Sandoval <osandov@osandov.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Orphans in the fs tree are cleaned up via open_ctree and subvolume
orphans are cleaned via btrfs_lookup_dentry -- except when a default
subvolume is in use. The name for the default subvolume uses a manual
lookup that doesn't trigger orphan cleanup and needs to trigger it
manually as well. This doesn't apply to the remount case since the
subvolumes are cleaned up by walking the root radix tree.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The private_data member of the Btrfs control device file
(/dev/btrfs-control) is used to hold the current transaction and needs
to be initialized to NULL to signify that no transaction is in progress.
We explicitly set the control file's private_data to NULL to be
independent of whatever value the misc subsystem initializes it to.
Backstory:
----------
The misc subsystem (which is used by /dev/btrfs-control) initializes
a file's private_data to point to the misc device when a driver has
registered a custom open file operation and initializes it to NULL
when a custom open file operation has *not* been provided.
This subtle quirk is confusing, to the point where kernel code registers
*empty* file open operations to have private_data point to the misc
device structure.
And it leads to bugs, where the addition or removal of a custom open
file operation surprisingly changes the initial contents of a file's
private_data structure.
To simplify things in the misc subsystem, a patch [1] has been proposed
to *always* set private_data to point to the misc device instead of
only doing this when a custom open file operation has been registered.
But before we can fix this in the misc subsystem itself, we need to
modify the (few) drivers that rely on this very subtle behavior.
[1] https://lkml.org/lkml/2014/12/4/939
Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Tom Van Braeckel <tomvanbraeckel@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
fiemap_fill_next_extent returns 0 on success, -errno on error, 1 if this was
the last extent that will fit in user array. If 1 is returned, the return
value may eventually returned to user space, which should not happen, according
to manpage of ioctl.
Signed-off-by: Chengyu Song <csong84@gatech.edu>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Due to insufficient check in btrfs_is_valid_xattr, this unexpectedly
works:
$ touch file
$ setfattr -n user. -v 1 file
$ getfattr -d file
user.="1"
ie. the missing attribute name after the namespace.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=94291
Reported-by: William Douglas <william.douglas@intel.com>
CC: <stable@vger.kernel.org> # 2.6.29+
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
While committing a transaction we free the log roots before we write the
new super block. Freeing the log roots implies marking the disk location
of every node/leaf (metadata extent) as pinned before the new super block
is written. This is to prevent the disk location of log metadata extents
from being reused before the new super block is written, otherwise we
would have a corrupted log tree if before the new super block is written
a crash/reboot happens and the location of any log tree metadata extent
ended up being reused and rewritten.
Even though we pinned the log tree's metadata extents, we were issuing a
discard against them if the fs was mounted with the -o discard option,
resulting in corruption of the log tree if a crash/reboot happened before
writing the new super block - the next time the fs was mounted, during
the log replay process we would find nodes/leafs of the log btree with
a content full of zeroes, causing the process to fail and require the
use of the tool btrfs-zero-log to wipeout the log tree (and all data
previously fsynced becoming lost forever).
Fix this by not doing a discard when pinning an extent. The discard will
be done later when it's safe (after the new super block is committed) at
extent-tree.c:btrfs_finish_extent_commit().
Fixes: e688b7252f (Btrfs: fix extent pinning bugs in the tree log)
CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We can get into inconsistency between inodes and directory entries
after fsyncing a directory. The issue is that while a directory gets
the new dentries persisted in the fsync log and replayed at mount time,
the link count of the inode that directory entries point to doesn't
get updated, staying with an incorrect link count (smaller then the
correct value). This later leads to stale file handle errors when
accessing (including attempt to delete) some of the links if all the
other ones are removed, which also implies impossibility to delete the
parent directories, since the dentries can not be removed.
Another issue is that (unlike ext3/4, xfs, f2fs, reiserfs, nilfs2),
when fsyncing a directory, new files aren't logged (their metadata and
dentries) nor any child directories. So this patch fixes this issue too,
since it has the same resolution as the incorrect inode link count issue
mentioned before.
This is very easy to reproduce, and the following excerpt from my test
case for xfstests shows how:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our main test file and directory.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 8K" $SCRATCH_MNT/foo | _filter_xfs_io
mkdir $SCRATCH_MNT/mydir
# Make sure all metadata and data are durably persisted.
sync
# Add a hard link to 'foo' inside our test directory and fsync only the
# directory. The btrfs fsync implementation had a bug that caused the new
# directory entry to be visible after the fsync log replay but, the inode
# of our file remained with a link count of 1.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/foo_2
# Add a few more links and new files.
# This is just to verify nothing breaks or gives incorrect results after the
# fsync log is replayed.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/foo_3
$XFS_IO_PROG -f -c "pwrite -S 0xff 0 64K" $SCRATCH_MNT/hello | _filter_xfs_io
ln $SCRATCH_MNT/hello $SCRATCH_MNT/mydir/hello_2
# Add some subdirectories and new files and links to them. This is to verify
# that after fsyncing our top level directory 'mydir', all the subdirectories
# and their files/links are registered in the fsync log and exist after the
# fsync log is replayed.
mkdir -p $SCRATCH_MNT/mydir/x/y/z
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/x/y/foo_y_link
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/x/y/z/foo_z_link
touch $SCRATCH_MNT/mydir/x/y/z/qwerty
# Now fsync only our top directory.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/mydir
# And fsync now our new file named 'hello', just to verify later that it has
# the expected content and that the previous fsync on the directory 'mydir' had
# no bad influence on this fsync.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/hello
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Verify the content of our file 'foo' remains the same as before, 8192 bytes,
# all with the value 0xaa.
echo "File 'foo' content after log replay:"
od -t x1 $SCRATCH_MNT/foo
# Remove the first name of our inode. Because of the directory fsync bug, the
# inode's link count was 1 instead of 5, so removing the 'foo' name ended up
# deleting the inode and the other names became stale directory entries (still
# visible to applications). Attempting to remove or access the remaining
# dentries pointing to that inode resulted in stale file handle errors and
# made it impossible to remove the parent directories since it was impossible
# for them to become empty.
echo "file 'foo' link count after log replay: $(stat -c %h $SCRATCH_MNT/foo)"
rm -f $SCRATCH_MNT/foo
# Now verify that all files, links and directories created before fsyncing our
# directory exist after the fsync log was replayed.
[ -f $SCRATCH_MNT/mydir/foo_2 ] || echo "Link mydir/foo_2 is missing"
[ -f $SCRATCH_MNT/mydir/foo_3 ] || echo "Link mydir/foo_3 is missing"
[ -f $SCRATCH_MNT/hello ] || echo "File hello is missing"
[ -f $SCRATCH_MNT/mydir/hello_2 ] || echo "Link mydir/hello_2 is missing"
[ -f $SCRATCH_MNT/mydir/x/y/foo_y_link ] || \
echo "Link mydir/x/y/foo_y_link is missing"
[ -f $SCRATCH_MNT/mydir/x/y/z/foo_z_link ] || \
echo "Link mydir/x/y/z/foo_z_link is missing"
[ -f $SCRATCH_MNT/mydir/x/y/z/qwerty ] || \
echo "File mydir/x/y/z/qwerty is missing"
# We expect our file here to have a size of 64Kb and all the bytes having the
# value 0xff.
echo "file 'hello' content after log replay:"
od -t x1 $SCRATCH_MNT/hello
# Now remove all files/links, under our test directory 'mydir', and verify we
# can remove all the directories.
rm -f $SCRATCH_MNT/mydir/x/y/z/*
rmdir $SCRATCH_MNT/mydir/x/y/z
rm -f $SCRATCH_MNT/mydir/x/y/*
rmdir $SCRATCH_MNT/mydir/x/y
rmdir $SCRATCH_MNT/mydir/x
rm -f $SCRATCH_MNT/mydir/*
rmdir $SCRATCH_MNT/mydir
# An fsck, run by the fstests framework everytime a test finishes, also detected
# the inconsistency and printed the following error message:
#
# root 5 inode 257 errors 2001, no inode item, link count wrong
# unresolved ref dir 258 index 2 namelen 5 name foo_2 filetype 1 errors 4, no inode ref
# unresolved ref dir 258 index 3 namelen 5 name foo_3 filetype 1 errors 4, no inode ref
status=0
exit
The expected golden output for the test is:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 65536/65536 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File 'foo' content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000
file 'foo' link count after log replay: 5
file 'hello' content after log replay:
0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0200000
Which is the output after this patch and when running the test against
ext3/4, xfs, f2fs, reiserfs or nilfs2. Without this patch, the test's
output is:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 65536/65536 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File 'foo' content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000
file 'foo' link count after log replay: 1
Link mydir/foo_2 is missing
Link mydir/foo_3 is missing
Link mydir/x/y/foo_y_link is missing
Link mydir/x/y/z/foo_z_link is missing
File mydir/x/y/z/qwerty is missing
file 'hello' content after log replay:
0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0200000
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/x/y/z': No such file or directory
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/x/y': No such file or directory
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/x': No such file or directory
rm: cannot remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/foo_2': Stale file handle
rm: cannot remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/foo_3': Stale file handle
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir': Directory not empty
Fsck, without this fix, also complains about the wrong link count:
root 5 inode 257 errors 2001, no inode item, link count wrong
unresolved ref dir 258 index 2 namelen 5 name foo_2 filetype 1 errors 4, no inode ref
unresolved ref dir 258 index 3 namelen 5 name foo_3 filetype 1 errors 4, no inode ref
So fix this by logging the inodes that the dentries point to when
fsyncing a directory.
A test case for xfstests follows.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
After looking at Liu Bo's recent patch (titled
"Btrfs: fix comp_oper to get right order") I realized the search made by
qgroup_oper_exists() was buggy because its rbtree navigation comparison
function, comp_oper_exist(), only looks at the fields bytenr and ref_root
of a tree node, ignoring the seq field completely. This was wrong because
when we insert a node into the rbtree we use comp_oper(), which takes a
decision based first on bytenr, then on seq and then on the ref_root field.
That means qgroup_oper_exists() could miss the fact that at least one
operation with given bytenr and ref_root exists.
Consider the following simple example of a 3 nodes qgroup operations
rbtree (created using comp_oper before this patch), where each node's key
is a tuple with the shape (bytenr, seq, ref_root, op):
[ (4096, 2, 20, op X) ]
/ \
/ \
[ (4096, 1, 5, op Y) ] [ (4096, 3, 10, op Z) ]
qgroup_oper_exists() when called to search for an existing operation for
bytenr 4096 and ref root 10 wouldn't find anything because it would go to
the left subtree instead of the right subtree, since comp_oper_exits()
ignores the seq field completely.
Fix this by changing the insertion navigation function to use the ref_root
field right after using the bytenr field and before using the seq field,
so that qgroup_oper_exists() / comp_oper_exist() work as expected.
This patch applies on top of the patch mentioned above from Liu.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we fallocate(), without the keep size flag, into an area already covered
by an extent previously fallocated, we were updating the inode's i_size but
we weren't updating the inode item in the fs/subvol tree. A following umount
+ mount would result in a loss of the inode's size (and an fsync would miss
too the fact that the inode changed).
Reproducer:
$ mkfs.btrfs -f /dev/sdd
$ mount /dev/sdd /mnt
$ fallocate -n -l 1M /mnt/foobar
$ fallocate -l 512K /mnt/foobar
$ umount /mnt
$ mount /dev/sdd /mnt
$ od -t x1 /mnt/foobar
0000000
The expected result is:
$ od -t x1 /mnt/foobar
0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
2000000
A test case for fstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
The logic to detect path loops when attempting to apply a pending
directory rename, introduced in commit
f959492fc1 (Btrfs: send, fix more issues related to directory renames)
is no longer needed, and the respective fstests test case for that commit,
btrfs/045, now passes without this code (as well as all the other test
cases for send/receive).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If a directory's reference ends up being orphanized, because the inode
currently being processed has a new path that matches that directory's
path, make sure we evict the name of the directory from the name cache.
This is because there might be descendent inodes (either directories or
regular files) that will be orphanized later too, and therefore the
orphan name of the ancestor must be used, otherwise we send issue rename
operations with a wrong path in the send stream.
Reproducer:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ mkdir -p /mnt/data/n1/n2/p1/p2
$ mkdir /mnt/data/n4
$ mkdir -p /mnt/data/p1/p2
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ mv /mnt/data/p1/p2 /mnt/data
$ mv /mnt/data/n1/n2/p1/p2 /mnt/data/p1
$ mv /mnt/data/p2 /mnt/data/n1/n2/p1
$ mv /mnt/data/n1/n2 /mnt/data/p1
$ mv /mnt/data/p1 /mnt/data/n4
$ mv /mnt/data/n4/p1/n2/p1 /mnt/data
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs send /mnt/snap1 -f /tmp/1.send
$ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.send
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt2
$ btrfs receive /mnt2 -f /tmp/1.send
$ btrfs receive /mnt2 -f /tmp/2.send
ERROR: rename data/p1/p2 -> data/n4/p1/p2 failed. no such file or directory
Directories data/p1 (inode 263) and data/p1/p2 (inode 264) in the parent
snapshot are both orphanized during the incremental send, and as soon as
data/p1 is orphanized, we must make sure that when orphanizing data/p1/p2
we use a source path of o263-6-o/p2 for the rename operation instead of
the old path data/p1/p2 (the one before the orphanization of inode 263).
A test case for xfstests follows soon.
Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If the clone root was not readonly or the dead flag was set on it, we were
leaving without decrementing the root's send_progress counter (and before
we just incremented it). If a concurrent snapshot deletion was in progress
and ended up being aborted, it would be impossible to later attempt to
delete again the snapshot, since the root's send_in_progress counter could
never go back to 0.
We were also setting clone_sources_to_rollback to i + 1 too early - if we
bailed out because the clone root we got is not readonly or flagged as dead
we ended up later derreferencing a null pointer because we didn't assign
the clone root to sctx->clone_roots[i].root:
for (i = 0; sctx && i < clone_sources_to_rollback; i++)
btrfs_root_dec_send_in_progress(
sctx->clone_roots[i].root);
So just don't increment the send_in_progress counter if the root is readonly
or flagged as dead.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
After we locked the root's root item, a concurrent snapshot deletion
call might have set the dead flag on it. So check if the dead flag
is set and abort if it is, just like we do for the parent root.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
If we deleted xattrs from a file and fsynced the file, after a log replay
the xattrs would remain associated to the file. This was an unexpected
behaviour and differs from what other filesystems do, such as for example
xfs and ext3/4.
Fix this by, on fsync log replay, check if every xattr in the fs/subvol
tree (that belongs to a logged inode) has a matching xattr in the log,
and if it does not, delete it from the fs/subvol tree. This is a similar
approach to what we do for dentries when we replay a directory from the
fsync log.
This issue is trivial to reproduce, and the following excerpt from my
test for xfstests triggers the issue:
_crash_and_mount()
{
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
}
rm -f $seqres.full
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create out test file and add 3 xattrs to it.
touch $SCRATCH_MNT/foobar
$SETFATTR_PROG -n user.attr1 -v val1 $SCRATCH_MNT/foobar
$SETFATTR_PROG -n user.attr2 -v val2 $SCRATCH_MNT/foobar
$SETFATTR_PROG -n user.attr3 -v val3 $SCRATCH_MNT/foobar
# Make sure everything is durably persisted.
sync
# Now delete the second xattr and fsync the inode.
$SETFATTR_PROG -x user.attr2 $SCRATCH_MNT/foobar
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foobar
_crash_and_mount
# After the fsync log is replayed, the file should have only 2 xattrs, the ones
# named user.attr1 and user.attr3. The btrfs fsync log replay bug left the file
# with the 3 xattrs that we had before deleting the second one and fsyncing the
# file.
echo "xattr names and values after first fsync log replay:"
$GETFATTR_PROG --absolute-names --dump $SCRATCH_MNT/foobar | _filter_scratch
# Now write some data to our file, fsync it, remove the first xattr, add a new
# hard link to our file and commit the fsync log by fsyncing some other new
# file. This is to verify that after log replay our first xattr does not exist
# anymore.
echo "hello world!" >> $SCRATCH_MNT/foobar
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foobar
$SETFATTR_PROG -x user.attr1 $SCRATCH_MNT/foobar
ln $SCRATCH_MNT/foobar $SCRATCH_MNT/foobar_link
touch $SCRATCH_MNT/qwerty
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/qwerty
_crash_and_mount
# Now only the xattr with name user.attr3 should be set in our file.
echo "xattr names and values after second fsync log replay:"
$GETFATTR_PROG --absolute-names --dump $SCRATCH_MNT/foobar | _filter_scratch
status=0
exit
The expected golden output, which is produced with this patch applied or
when testing against xfs or ext3/4, is:
xattr names and values after first fsync log replay:
# file: SCRATCH_MNT/foobar
user.attr1="val1"
user.attr3="val3"
xattr names and values after second fsync log replay:
# file: SCRATCH_MNT/foobar
user.attr3="val3"
Without this patch applied, the output is:
xattr names and values after first fsync log replay:
# file: SCRATCH_MNT/foobar
user.attr1="val1"
user.attr2="val2"
user.attr3="val3"
xattr names and values after second fsync log replay:
# file: SCRATCH_MNT/foobar
user.attr1="val1"
user.attr2="val2"
user.attr3="val3"
A patch with a test case for xfstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull btrfs fixes from Chris Mason:
"Most of these are fixing extent reservation accounting, or corners
with tree writeback during commit.
Josef's set does add a test, which isn't strictly a fix, but it'll
keep us from making this same mistake again"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix outstanding_extents accounting in DIO
Btrfs: add sanity test for outstanding_extents accounting
Btrfs: just free dummy extent buffers
Btrfs: account merges/splits properly
Btrfs: prepare block group cache before writing
Btrfs: fix ASSERT(list_empty(&cur_trans->dirty_bgs_list)
Btrfs: account for the correct number of extents for delalloc reservations
Btrfs: fix merge delalloc logic
Btrfs: fix comp_oper to get right order
Btrfs: catch transaction abortion after waiting for it
btrfs: fix sizeof format specifier in btrfs_check_super_valid()
We are keeping track of how many extents we need to reserve properly based on
the amount we want to write, but we were still incrementing outstanding_extents
if we wrote less than what we requested. This isn't quite right since we will
be limited to our max extent size. So instead lets do something horrible! Keep
track of how many outstanding_extents we reserved, and decrement each time we
allocate an extent. If we use our entire reserve make sure to jack up
outstanding_extents on the inode so the accounting works out properly. Thanks,
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
I introduced a regression wrt outstanding_extents accounting. These are tricky
areas that aren't easily covered by xfstests as we could change MAX_EXTENT_SIZE
at any time. So add sanity tests to cover the various conditions that are
tricky in order to make sure we don't introduce regressions in the future.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
If we fail during our sanity tests we could get NULL deref's because we unload
the module before the dummy extent buffers are free'd via RCU. So check for
this case and just free the things directly. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
My fix
Btrfs: fix merge delalloc logic
only fixed half of the problems, it didn't fix the case where we have two large
extents on either side and then join them together with a new small extent. We
need to instead keep track of how many extents we have accounted for with each
side of the new extent, and then see how many extents we need for the new large
extent. If they match then we know we need to keep our reservation, otherwise
we need to drop our reservation. This shows up with a case like this
[BTRFS_MAX_EXTENT_SIZE+4K][4K HOLE][BTRFS_MAX_EXTENT_SIZE+4K]
Previously the logic would have said that the number extents required for the
new size (3) is larger than the number of extents required for the largest side
(2) therefore we need to keep our reservation. But this isn't the case, since
both sides require a reservation of 2 which leads to 4 for the whole range
currently reserved, but we only need 3, so we need to drop one of the
reservations. The same problem existed for splits, we'd think we only need 3
extents when creating the hole but in reality we need 4. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Writing the block group cache will modify the extent tree quite a bit because it
truncates the old space cache and pre-allocates new stuff. To try and cut down
on the churn lets do the setup dance first, then later on hopefully we can avoid
looping with newly dirtied roots. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Dave could hit this assert consistently running btrfs/078. This is because
when we update the block groups we could truncate the free space, which would
try to delete the csums for that range and dirty the csum root. For this to
happen we have to have already written out the csum root so it's kind of hard to
hit this case. This patch fixes this by changing the logic to only write the
dirty block groups if the dirty_cowonly_roots list is empty. This will get us
the same effect as before since we add the extent root last, and will cover the
case that we dirty some other root again but not the extent root. Thanks,
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Direct IO can easily pass in an buffer that is greater than
BTRFS_MAX_EXTENT_SIZE, so take this into account when reserving extents in the
delalloc reservation code. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
My patch to properly count outstanding extents wrt MAX_EXTENT_SIZE introduced a
regression when re-dirtying already dirty areas. We have logic in split to make
sure we are taking the largest space into account but didn't have it for merge,
so it was sometimes making us think we were turning a tiny extent into a huge
extent, when in reality we already had a huge extent and needed to use the other
side in our logic. This fixes the regression that was reported by a user on
list. Thanks,
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Case (oper1->seq > oper2->seq) should differ with case (oper1->seq < oper2->seq).
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
This problem is uncovered by a test case: http://patchwork.ozlabs.org/patch/244297.
Fsync() can report success when it actually doesn't. When we
have several threads running fsync() at the same tiem and in one fsync() we
get a transaction abortion due to some problems(in the test case it's disk
failures), and other fsync()s may return successfully which makes userspace
programs think that data is now safely flushed into disk.
It's because that after fsyncs() fail btrfs_sync_log() due to disk failures,
they get to try btrfs_commit_transaction() where it finds that there is
already a transaction being committed, and they'll just call wait_for_commit()
and return. Note that we actually check "trans->aborted" in btrfs_end_transaction,
but it's likely that the error message is still not yet throwed out and only after
wait_for_commit() we're sure whether the transaction is committed successfully.
This add the necessary check and it now passes the test.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
This patch fixes mips compilation warning:
fs/btrfs/disk-io.c: In function 'btrfs_check_super_valid':
fs/btrfs/disk-io.c:3927:21: warning: format '%lu' expects argument
of type 'long unsigned int', but argument 3 has type 'unsigned int' [-Wformat]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"Outside of misc fixes, Filipe has a few fsync corners and we're
pulling in one more of Josef's fixes from production use here"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs:__add_inode_ref: out of bounds memory read when looking for extended ref.
Btrfs: fix data loss in the fast fsync path
Btrfs: remove extra run_delayed_refs in update_cowonly_root
Btrfs: incremental send, don't rename a directory too soon
btrfs: fix lost return value due to variable shadowing
Btrfs: do not ignore errors from btrfs_lookup_xattr in do_setxattr
Btrfs: fix off-by-one logic error in btrfs_realloc_node
Btrfs: add missing inode update when punching hole
Btrfs: abort the transaction if we fail to update the free space cache inode
Btrfs: fix fsync race leading to ordered extent memory leaks
Improper arithmetics when calculting the address of the extended ref could
lead to an out of bounds memory read and kernel panic.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
cc: stable@vger.kernel.org # v3.7+
Signed-off-by: Chris Mason <clm@fb.com>
When using the fast file fsync code path we can miss the fact that new
writes happened since the last file fsync and therefore return without
waiting for the IO to finish and write the new extents to the fsync log.
Here's an example scenario where the fsync will miss the fact that new
file data exists that wasn't yet durably persisted:
1. fs_info->last_trans_committed == N - 1 and current transaction is
transaction N (fs_info->generation == N);
2. do a buffered write;
3. fsync our inode, this clears our inode's full sync flag, starts
an ordered extent and waits for it to complete - when it completes
at btrfs_finish_ordered_io(), the inode's last_trans is set to the
value N (via btrfs_update_inode_fallback -> btrfs_update_inode ->
btrfs_set_inode_last_trans);
4. transaction N is committed, so fs_info->last_trans_committed is now
set to the value N and fs_info->generation remains with the value N;
5. do another buffered write, when this happens btrfs_file_write_iter
sets our inode's last_trans to the value N + 1 (that is
fs_info->generation + 1 == N + 1);
6. transaction N + 1 is started and fs_info->generation now has the
value N + 1;
7. transaction N + 1 is committed, so fs_info->last_trans_committed
is set to the value N + 1;
8. fsync our inode - because it doesn't have the full sync flag set,
we only start the ordered extent, we don't wait for it to complete
(only in a later phase) therefore its last_trans field has the
value N + 1 set previously by btrfs_file_write_iter(), and so we
have:
inode->last_trans <= fs_info->last_trans_committed
(N + 1) (N + 1)
Which made us not log the last buffered write and exit the fsync
handler immediately, returning success (0) to user space and resulting
in data loss after a crash.
This can actually be triggered deterministically and the following excerpt
from a testcase I made for xfstests triggers the issue. It moves a dummy
file across directories and then fsyncs the old parent directory - this
is just to trigger a transaction commit, so moving files around isn't
directly related to the issue but it was chosen because running 'sync' for
example does more than just committing the current transaction, as it
flushes/waits for all file data to be persisted. The issue can also happen
at random periods, since the transaction kthread periodicaly commits the
current transaction (about every 30 seconds by default).
The body of the test is:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our main test file 'foo', the one we check for data loss.
# By doing an fsync against our file, it makes btrfs clear the 'needs_full_sync'
# bit from its flags (btrfs inode specific flags).
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 8K" \
-c "fsync" $SCRATCH_MNT/foo | _filter_xfs_io
# Now create one other file and 2 directories. We will move this second file
# from one directory to the other later because it forces btrfs to commit its
# currently open transaction if we fsync the old parent directory. This is
# necessary to trigger the data loss bug that affected btrfs.
mkdir $SCRATCH_MNT/testdir_1
touch $SCRATCH_MNT/testdir_1/bar
mkdir $SCRATCH_MNT/testdir_2
# Make sure everything is durably persisted.
sync
# Write more 8Kb of data to our file.
$XFS_IO_PROG -c "pwrite -S 0xbb 8K 8K" $SCRATCH_MNT/foo | _filter_xfs_io
# Move our 'bar' file into a new directory.
mv $SCRATCH_MNT/testdir_1/bar $SCRATCH_MNT/testdir_2/bar
# Fsync our first directory. Because it had a file moved into some other
# directory, this made btrfs commit the currently open transaction. This is
# a condition necessary to trigger the data loss bug.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/testdir_1
# Now fsync our main test file. If the fsync succeeds, we expect the 8Kb of
# data we wrote previously to be persisted and available if a crash happens.
# This did not happen with btrfs, because of the transaction commit that
# happened when we fsynced the parent directory.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Now check that all data we wrote before are available.
echo "File content after log replay:"
od -t x1 $SCRATCH_MNT/foo
status=0
exit
The expected golden output for the test, which is what we get with this
fix applied (or when running against ext3/4 and xfs), is:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 8192/8192 bytes at offset 8192
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000 bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
*
0040000
Without this fix applied, the output shows the test file does not have
the second 8Kb extent that we successfully fsynced:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 8192/8192 bytes at offset 8192
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000
So fix this by skipping the fsync only if we're doing a full sync and
if the inode's last_trans is <= fs_info->last_trans_committed, or if
the inode is already in the log. Also remove setting the inode's
last_trans in btrfs_file_write_iter since it's useless/unreliable.
Also because btrfs_file_write_iter no longer sets inode->last_trans to
fs_info->generation + 1, don't set last_trans to 0 if we bail out and don't
bail out if last_trans is 0, otherwise something as simple as the following
example wouldn't log the second write on the last fsync:
1. write to file
2. fsync file
3. fsync file
|--> btrfs_inode_in_log() returns true and it set last_trans to 0
4. write to file
|--> btrfs_file_write_iter() no longers sets last_trans, so it
remained with a value of 0
5. fsync
|--> inode->last_trans == 0, so it bails out without logging the
second write
A test case for xfstests will be sent soon.
CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
1) We can safely use the function's 'i'. Fixes warning
fs/btrfs/volumes.c:5257:7: warning: declaration of 'i' shadows a previous local
fs/btrfs/volumes.c:4951:6: warning: shadowed declaration is here
2) A local variable duplicates name of an argument, we can use the value
directly. Fixes warning
fs/btrfs/volumes.c:5433:8: warning: declaration of 'length' shadows a parameter
fs/btrfs/volumes.c:4935:27: warning: shadowed declaration is here
Signed-off-by: David Sterba <dsterba@suse.cz>
The conversion macros use nested container_of that leads to a warning
fs/btrfs/sysfs.c: In function 'btrfs_feature_visible':
fs/btrfs/sysfs.c:183:8: warning: declaration of '__mptr' shadows a previous local
fs/btrfs/sysfs.c:183:8: warning: shadowed declaration is here
Use of functions will add proper type checking.
Signed-off-by: David Sterba <dsterba@suse.cz>
The divisor is derived from nodesize or PAGE_SIZE, fits into 32bit type.
Get rid of a few more do_div instances.
Signed-off-by: David Sterba <dsterba@suse.cz>
Using {} as initializer for struct seq_elem does not properly initialize
the list_head member, but it currently works because it gets set through
btrfs_get_tree_mod_seq if 'seq' is 0.
Signed-off-by: David Sterba <dsterba@suse.cz>
There are lockstart and lockend defined in the function and not used
after their duplicate definition scope ends, it's safe to reuse them.
Signed-off-by: David Sterba <dsterba@suse.cz>
Convert kmalloc(nr * size, ..) to kmalloc_array that does additional
overflow checks, the zeroing variant is kcalloc.
Signed-off-by: David Sterba <dsterba@suse.cz>
Switch to div_u64 if the divisor is a numeric constant or sum of
sizeof()s. We can remove a few instances of do_div that has the hidden
semtantics of changing the 1st argument.
Small power-of-two divisors are converted to bitshifts, large values are
kept intact for clarity.
Signed-off-by: David Sterba <dsterba@suse.cz>
Clean the opencoded variant, cond_resched_lock also checks the lock for
contention so it might help in some cases that were not covered by
simple need_resched().
Signed-off-by: David Sterba <dsterba@suse.cz>
There's one more case where we can't issue a rename operation for a
directory as soon as we process it. We used to delay directory renames
only if they have some ancestor directory with a higher inode number
that got renamed too, but there's another case where we need to delay
the rename too - when a directory A is renamed to the old name of a
directory B but that directory B has its rename delayed because it
has now (in the send root) an ancestor with a higher inode number that
was renamed. If we don't delay the directory rename in this case, the
receiving end of the send stream will attempt to rename A to the old
name of B before B got renamed to its new name, which results in a
"directory not empty" error. So fix this by delaying directory renames
for this case too.
Steps to reproduce:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ mkdir /mnt/a
$ mkdir /mnt/b
$ mkdir /mnt/c
$ touch /mnt/a/file
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ mv /mnt/c /mnt/x
$ mv /mnt/a /mnt/x/y
$ mv /mnt/b /mnt/a
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs send /mnt/snap1 -f /tmp/1.send
$ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.send
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt2
$ btrfs receive /mnt2 -f /tmp/1.send
$ btrfs receive /mnt2 -f /tmp/2.send
ERROR: rename b -> a failed. Directory not empty
A test case for xfstests follows soon.
Reported-by: Ames Cornish <ames@cornishes.net>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
A block-local variable stores error code but btrfs_get_blocks_direct may
not return it in the end as there's a ret defined in the function scope.
CC: <stable@vger.kernel.org> # 3.6+
Fixes: d187663ef2 ("Btrfs: lock extents as we map them in DIO")
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The return value from btrfs_lookup_xattr() can be a pointer encoding an
error, therefore deal with it. This fixes commit 5f5bc6b1e2
("Btrfs: make xattr replace operations atomic").
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The end_slot variable actually matches the number of pointers in the
node and not the last slot (which is 'nritems - 1'). Therefore in order
to check that the current slot in the for loop doesn't match the last
one, the correct logic is to check if 'i' is less than 'end_slot - 1'
and not 'end_slot - 2'.
Fix this and set end_slot to be 'nritems - 1', as it's less confusing
since the variable name implies it's inclusive rather then exclusive.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When punching a file hole if we endup only zeroing parts of a page,
because the start offset isn't a multiple of the sector size or the
start offset and length fall within the same page, we were not updating
the inode item. This prevented an fsync from doing anything, if no other
file changes happened in the current transaction, because the fields
in btrfs_inode used to check if the inode needs to be fsync'ed weren't
updated.
This issue is easy to reproduce and the following excerpt from the
xfstest case I made shows how to trigger it:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test file.
$XFS_IO_PROG -f -c "pwrite -S 0x22 -b 16K 0 16K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Fsync the file, this makes btrfs update some btrfs inode specific fields
# that are used to track if the inode needs to be written/updated to the fsync
# log or not. After this fsync, the new values for those fields indicate that
# a subsequent fsync does not need to touch the fsync log.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Force a commit of the current transaction. After this point, any operation
# that modifies the data or metadata of our file, should update those fields in
# the btrfs inode with values that make the next fsync operation write to the
# fsync log.
sync
# Punch a hole in our file. This small range affects only 1 page.
# This made the btrfs hole punching implementation write only some zeroes in
# one page, but it did not update the btrfs inode fields used to determine if
# the next fsync needs to write to the fsync log.
$XFS_IO_PROG -c "fpunch 8000 4K" $SCRATCH_MNT/foo
# Another variation of the previously mentioned case.
$XFS_IO_PROG -c "fpunch 15000 100" $SCRATCH_MNT/foo
# Now fsync the file. This was a no-operation because the previous hole punch
# operation didn't update the inode's fields mentioned before, so they remained
# with the values they had after the first fsync - that is, they indicate that
# it is not needed to write to fsync log.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
echo "File content before:"
od -t x1 $SCRATCH_MNT/foo
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Enable writes and mount the fs. This makes the fsync log replay code run.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Because the last fsync didn't do anything, here the file content matched what
# it was after the first fsync, before the holes were punched, and not what it
# was after the holes were punched.
echo "File content after:"
od -t x1 $SCRATCH_MNT/foo
This issue has been around since 2012, when the punch hole implementation
was added, commit 2aaa665581 ("Btrfs: add hole punching").
A test case for xfstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Our gluster boxes were hitting a problem where they'd run out of space when
updating the block group cache and therefore wouldn't be able to update the free
space inode. This is a problem because this is how we invalidate the cache and
protect ourselves from errors further down the stack, so if this fails we have
to abort the transaction so we make sure we don't end up with stale free space
cache. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
We can have multiple fsync operations against the same file during the
same transaction and they can collect the same ordered extents while they
don't complete (still accessible from the inode's ordered tree). If this
happens, those ordered extents will never get their reference counts
decremented to 0, leading to memory leaks and inode leaks (an iput for an
ordered extent's inode is scheduled only when the ordered extent's refcount
drops to 0). The following sequence diagram explains this race:
CPU 1 CPU 2
btrfs_sync_file()
btrfs_sync_file()
mutex_lock(inode->i_mutex)
btrfs_log_inode()
btrfs_get_logged_extents()
--> collects ordered extent X
--> increments ordered
extent X's refcount
btrfs_submit_logged_extents()
mutex_unlock(inode->i_mutex)
mutex_lock(inode->i_mutex)
btrfs_sync_log()
btrfs_wait_logged_extents()
--> list_del_init(&ordered->log_list)
btrfs_log_inode()
btrfs_get_logged_extents()
--> Adds ordered extent X
to logged_list because
at this point:
list_empty(&ordered->log_list)
&& test_bit(BTRFS_ORDERED_LOGGED,
&ordered->flags) == 0
--> Increments ordered extent
X's refcount
--> check if ordered extent's io is
finished or not, start it if
necessary and wait for it to finish
--> sets bit BTRFS_ORDERED_LOGGED
on ordered extent X's flags
and adds it to trans->ordered
btrfs_sync_log() finishes
btrfs_submit_logged_extents()
btrfs_log_inode() finishes
mutex_unlock(inode->i_mutex)
btrfs_sync_file() finishes
btrfs_sync_log()
btrfs_wait_logged_extents()
--> Sees ordered extent X has the
bit BTRFS_ORDERED_LOGGED set in
its flags
--> X's refcount is untouched
btrfs_sync_log() finishes
btrfs_sync_file() finishes
btrfs_commit_transaction()
--> called by transaction kthread for e.g.
btrfs_wait_pending_ordered()
--> waits for ordered extent X to
complete
--> decrements ordered extent X's
refcount by 1 only, corresponding
to the increment done by the fsync
task ran by CPU 1
In the scenario of the above diagram, after the transaction commit,
the ordered extent will remain with a refcount of 1 forever, leaking
the ordered extent structure and preventing the i_count of its inode
from ever decreasing to 0, since the delayed iput is scheduled only
when the ordered extent's refcount drops to 0, preventing the inode
from ever being evicted by the VFS.
Fix this by using the flag BTRFS_ORDERED_LOGGED differently. Use it to
mean that an ordered extent is already being processed by an fsync call,
which will attach it to the current transaction, preventing it from being
collected by subsequent fsync operations against the same inode.
This race was introduced with the following change (added in 3.19 and
backported to stable 3.18 and 3.17):
Btrfs: make sure logged extents complete in the current transaction V3
commit 50d9aa99bd
I ran into this issue while running xfstests/generic/113 in a loop, which
failed about 1 out of 10 runs with the following warning in dmesg:
[ 2612.440038] WARNING: CPU: 4 PID: 22057 at fs/btrfs/disk-io.c:3558 free_fs_root+0x36/0x133 [btrfs]()
[ 2612.442810] Modules linked in: btrfs crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop processor parport_pc parport psmouse therma
l_sys i2c_piix4 serio_raw pcspkr evdev microcode button i2c_core ext4 crc16 jbd2 mbcache sd_mod sg sr_mod cdrom virtio_scsi ata_generic virtio_pci ata_piix virtio_ring libata virtio flo
ppy e1000 scsi_mod [last unloaded: btrfs]
[ 2612.452711] CPU: 4 PID: 22057 Comm: umount Tainted: G W 3.19.0-rc5-btrfs-next-4+ #1
[ 2612.454921] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[ 2612.457709] 0000000000000009 ffff8801342c3c78 ffffffff8142425e ffff88023ec8f2d8
[ 2612.459829] 0000000000000000 ffff8801342c3cb8 ffffffff81045308 ffff880046460000
[ 2612.461564] ffffffffa036da56 ffff88003d07b000 ffff880046460000 ffff880046460068
[ 2612.463163] Call Trace:
[ 2612.463719] [<ffffffff8142425e>] dump_stack+0x4c/0x65
[ 2612.464789] [<ffffffff81045308>] warn_slowpath_common+0xa1/0xbb
[ 2612.466026] [<ffffffffa036da56>] ? free_fs_root+0x36/0x133 [btrfs]
[ 2612.467247] [<ffffffff810453c5>] warn_slowpath_null+0x1a/0x1c
[ 2612.468416] [<ffffffffa036da56>] free_fs_root+0x36/0x133 [btrfs]
[ 2612.469625] [<ffffffffa036f2a7>] btrfs_drop_and_free_fs_root+0x93/0x9b [btrfs]
[ 2612.471251] [<ffffffffa036f353>] btrfs_free_fs_roots+0xa4/0xd6 [btrfs]
[ 2612.472536] [<ffffffff8142612e>] ? wait_for_completion+0x24/0x26
[ 2612.473742] [<ffffffffa0370bbc>] close_ctree+0x1f3/0x33c [btrfs]
[ 2612.475477] [<ffffffff81059d1d>] ? destroy_workqueue+0x148/0x1ba
[ 2612.476695] [<ffffffffa034e3da>] btrfs_put_super+0x19/0x1b [btrfs]
[ 2612.477911] [<ffffffff81153e53>] generic_shutdown_super+0x73/0xef
[ 2612.479106] [<ffffffff811540e2>] kill_anon_super+0x13/0x1e
[ 2612.480226] [<ffffffffa034e1e3>] btrfs_kill_super+0x17/0x23 [btrfs]
[ 2612.481471] [<ffffffff81154307>] deactivate_locked_super+0x3b/0x50
[ 2612.482686] [<ffffffff811547a7>] deactivate_super+0x3f/0x43
[ 2612.483791] [<ffffffff8116b3ed>] cleanup_mnt+0x59/0x78
[ 2612.484842] [<ffffffff8116b44c>] __cleanup_mnt+0x12/0x14
[ 2612.485900] [<ffffffff8105d019>] task_work_run+0x8f/0xbc
[ 2612.486960] [<ffffffff810028d8>] do_notify_resume+0x5a/0x6b
[ 2612.488083] [<ffffffff81236e5b>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 2612.489333] [<ffffffff8142a17f>] int_signal+0x12/0x17
[ 2612.490353] ---[ end trace 54a960a6bdcb8d93 ]---
[ 2612.557253] VFS: Busy inodes after unmount of sdb. Self-destruct in 5 seconds. Have a nice day...
Kmemleak confirmed the ordered extent leak (and btrfs inode specific
structures such as delayed nodes):
$ cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff880154290db0 (size 576):
comm "btrfsck", pid 21980, jiffies 4295542503 (age 1273.412s)
hex dump (first 32 bytes):
01 40 00 00 01 00 00 00 b0 1d f1 4e 01 88 ff ff .@.........N....
00 00 00 00 00 00 00 00 c8 0d 29 54 01 88 ff ff ..........)T....
backtrace:
[<ffffffff8141d74d>] kmemleak_update_trace+0x4c/0x6a
[<ffffffff8122f2c0>] radix_tree_node_alloc+0x6d/0x83
[<ffffffff8122fb26>] __radix_tree_create+0x109/0x190
[<ffffffff8122fbdd>] radix_tree_insert+0x30/0xac
[<ffffffffa03b9bde>] btrfs_get_or_create_delayed_node+0x130/0x187 [btrfs]
[<ffffffffa03bb82d>] btrfs_delayed_delete_inode_ref+0x32/0xac [btrfs]
[<ffffffffa0379dae>] __btrfs_unlink_inode+0xee/0x288 [btrfs]
[<ffffffffa037c715>] btrfs_unlink_inode+0x1e/0x40 [btrfs]
[<ffffffffa037c797>] btrfs_unlink+0x60/0x9b [btrfs]
[<ffffffff8115d7f0>] vfs_unlink+0x9c/0xed
[<ffffffff8115f5de>] do_unlinkat+0x12c/0x1fa
[<ffffffff811601a7>] SyS_unlinkat+0x29/0x2b
[<ffffffff81429e92>] system_call_fastpath+0x12/0x17
[<ffffffffffffffff>] 0xffffffffffffffff
unreferenced object 0xffff88014ef11db0 (size 576):
comm "rm", pid 22009, jiffies 4295542593 (age 1273.052s)
hex dump (first 32 bytes):
02 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 c8 1d f1 4e 01 88 ff ff ...........N....
backtrace:
[<ffffffff8141d74d>] kmemleak_update_trace+0x4c/0x6a
[<ffffffff8122f2c0>] radix_tree_node_alloc+0x6d/0x83
[<ffffffff8122fb26>] __radix_tree_create+0x109/0x190
[<ffffffff8122fbdd>] radix_tree_insert+0x30/0xac
[<ffffffffa03b9bde>] btrfs_get_or_create_delayed_node+0x130/0x187 [btrfs]
[<ffffffffa03bb82d>] btrfs_delayed_delete_inode_ref+0x32/0xac [btrfs]
[<ffffffffa0379dae>] __btrfs_unlink_inode+0xee/0x288 [btrfs]
[<ffffffffa037c715>] btrfs_unlink_inode+0x1e/0x40 [btrfs]
[<ffffffffa037c797>] btrfs_unlink+0x60/0x9b [btrfs]
[<ffffffff8115d7f0>] vfs_unlink+0x9c/0xed
[<ffffffff8115f5de>] do_unlinkat+0x12c/0x1fa
[<ffffffff811601a7>] SyS_unlinkat+0x29/0x2b
[<ffffffff81429e92>] system_call_fastpath+0x12/0x17
[<ffffffffffffffff>] 0xffffffffffffffff
unreferenced object 0xffff8800336feda8 (size 584):
comm "aio-stress", pid 22031, jiffies 4295543006 (age 1271.400s)
hex dump (first 32 bytes):
00 40 3e 00 00 00 00 00 00 00 8f 42 00 00 00 00 .@>........B....
00 00 01 00 00 00 00 00 00 00 01 00 00 00 00 00 ................
backtrace:
[<ffffffff8114eb34>] create_object+0x172/0x29a
[<ffffffff8141d790>] kmemleak_alloc+0x25/0x41
[<ffffffff81141ae6>] kmemleak_alloc_recursive.constprop.52+0x16/0x18
[<ffffffff81145288>] kmem_cache_alloc+0xf7/0x198
[<ffffffffa0389243>] __btrfs_add_ordered_extent+0x43/0x309 [btrfs]
[<ffffffffa038968b>] btrfs_add_ordered_extent_dio+0x12/0x14 [btrfs]
[<ffffffffa03810e2>] btrfs_get_blocks_direct+0x3ef/0x571 [btrfs]
[<ffffffff81181349>] do_blockdev_direct_IO+0x62a/0xb47
[<ffffffff8118189a>] __blockdev_direct_IO+0x34/0x36
[<ffffffffa03776e5>] btrfs_direct_IO+0x16a/0x1e8 [btrfs]
[<ffffffff81100373>] generic_file_direct_write+0xb8/0x12d
[<ffffffffa038615c>] btrfs_file_write_iter+0x24b/0x42f [btrfs]
[<ffffffff8118bb0d>] aio_run_iocb+0x2b7/0x32e
[<ffffffff8118c99a>] do_io_submit+0x26e/0x2ff
[<ffffffff8118ca3b>] SyS_io_submit+0x10/0x12
[<ffffffff81429e92>] system_call_fastpath+0x12/0x17
CC: <stable@vger.kernel.org> # 3.19, 3.18 and 3.17
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fix from Chris Mason:
"I'm still testing more fixes, but I wanted to get out the fix for the
btrfs raid5/6 memory corruption I mentioned in my merge window pull"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix allocation size calculations in alloc_btrfs_bio
Pull more vfs updates from Al Viro:
"Assorted stuff from this cycle. The big ones here are multilayer
overlayfs from Miklos and beginning of sorting ->d_inode accesses out
from David"
* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (51 commits)
autofs4 copy_dev_ioctl(): keep the value of ->size we'd used for allocation
procfs: fix race between symlink removals and traversals
debugfs: leave freeing a symlink body until inode eviction
Documentation/filesystems/Locking: ->get_sb() is long gone
trylock_super(): replacement for grab_super_passive()
fanotify: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
Cachefiles: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)
SELinux: Use d_is_positive() rather than testing dentry->d_inode
Smack: Use d_is_positive() rather than testing dentry->d_inode
TOMOYO: Use d_is_dir() rather than d_inode and S_ISDIR()
Apparmor: Use d_is_positive/negative() rather than testing dentry->d_inode
Apparmor: mediated_filesystem() should use dentry->d_sb not inode->i_sb
VFS: Split DCACHE_FILE_TYPE into regular and special types
VFS: Add a fallthrough flag for marking virtual dentries
VFS: Add a whiteout dentry type
VFS: Introduce inode-getting helpers for layered/unioned fs environments
Infiniband: Fix potential NULL d_inode dereference
posix_acl: fix reference leaks in posix_acl_create
autofs4: Wrong format for printing dentry
...
Convert the following where appropriate:
(1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).
(2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).
(3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more
complicated than it appears as some calls should be converted to
d_can_lookup() instead. The difference is whether the directory in
question is a real dir with a ->lookup op or whether it's a fake dir with
a ->d_automount op.
In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).
Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer. In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.
However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.
There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was
intended for special directory entry types that don't have attached inodes.
The following perl+coccinelle script was used:
use strict;
my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
print "No matches\n";
exit(0);
}
my @cocci = (
'@@',
'expression E;',
'@@',
'',
'- S_ISLNK(E->d_inode->i_mode)',
'+ d_is_symlink(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISDIR(E->d_inode->i_mode)',
'+ d_is_dir(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISREG(E->d_inode->i_mode)',
'+ d_is_reg(E)' );
my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);
foreach my $file (@callers) {
chomp $file;
print "Processing ", $file, "\n";
system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
die "spatch failed";
}
[AV: overlayfs parts skipped]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Since commit 8e5cfb55d3 (Btrfs: Make raid_map array be inlined in
btrfs_bio structure), the raid map array is allocated along with the
btrfs bio in alloc_btrfs_bio. The calculation used to decide how much
we need to allocate was using the wrong parameter passed into the
allocation function.
The passed in real_stripes will be zero if a target replace operation
is not currently running. We want to use total_stripes instead.
Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: David Sterba <dsterba@suse.cz>
Tested-by: David Sterba <dsterba@suse.cz>
Pull btrfs updates from Chris Mason:
"This pull is mostly cleanups and fixes:
- The raid5/6 cleanups from Zhao Lei fixup some long standing warts
in the code and add improvements on top of the scrubbing support
from 3.19.
- Josef has round one of our ENOSPC fixes coming from large btrfs
clusters here at FB.
- Dave Sterba continues a long series of cleanups (thanks Dave), and
Filipe continues hammering on corner cases in fsync and others
This all was held up a little trying to track down a use-after-free in
btrfs raid5/6. It's not clear yet if this is just made easier to
trigger with this pull or if its a new bug from the raid5/6 cleanups.
Dave Sterba is the only one to trigger it so far, but he has a
consistent way to reproduce, so we'll get it nailed shortly"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (68 commits)
Btrfs: don't remove extents and xattrs when logging new names
Btrfs: fix fsync data loss after adding hard link to inode
Btrfs: fix BUG_ON in btrfs_orphan_add() when delete unused block group
Btrfs: account for large extents with enospc
Btrfs: don't set and clear delalloc for O_DIRECT writes
Btrfs: only adjust outstanding_extents when we do a short write
btrfs: Fix out-of-space bug
Btrfs: scrub, fix sleep in atomic context
Btrfs: fix scheduler warning when syncing log
Btrfs: Remove unnecessary placeholder in btrfs_err_code
btrfs: cleanup init for list in free-space-cache
btrfs: delete chunk allocation attemp when setting block group ro
btrfs: clear bio reference after submit_one_bio()
Btrfs: fix scrub race leading to use-after-free
Btrfs: add missing cleanup on sysfs init failure
Btrfs: fix race between transaction commit and empty block group removal
btrfs: add more checks to btrfs_read_sys_array
btrfs: cleanup, rename a few variables in btrfs_read_sys_array
btrfs: add checks for sys_chunk_array sizes
btrfs: more superblock checks, lower bounds on devices and sectorsize/nodesize
...
Also, remove the two local variables create_uuid_tree
and check_uuid_tree; we can use the existence of
the uuid root and/or the RESCAN_UUID_TREE flag to
determine what action to take.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
close_ctree() has a local fs_info var for convienience;
use it consistently.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
The commit:
8dabb74 Btrfs: change core code of btrfs to support the
device replace operations
added the fs_info argument, but never used it -
just remove it again.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
This patch fixes mips compilation warning:
fs/btrfs/disk-io.c: In function 'btrfs_check_super_valid':
fs/btrfs/disk-io.c:3927:21: warning: format '%lu' expects argument
of type 'long unsigned int', but argument 3 has type 'unsigned int' [-Wformat]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David Sterba <dsterba@suse.cz>
for() is obviously better in these code block, and remove noused
init-value to reduce about 6 bytes binary size.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: David Sterba <dsterba@suse.cz>
There functions include unused chunk_tree argument from the begining,
it is time to remove them and clean up relative code to prepare value
of this argument in caller.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
int alloc_chunk is never used in this function, remove it.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
There are some op tables that can be easily made const, similarly the
sysfs feature and raid tables. This is motivated by PaX CONSTIFY plugin.
Signed-off-by: David Sterba <dsterba@suse.cz>
A new helper kvfree() in mm/utils.c will do this.
Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
This is the 3rd independent patch of a larger project to cleanup btrfs's
internal usage of btrfs_root. Many functions take btrfs_root only to
grab the fs_info struct.
By requiring a root these functions cause programmer overhead. That
these functions can accept any valid root is not obvious until
inspection.
This patch reduces the specificity of such functions to accept the
fs_info directly.
These patches can be applied independently and thus are not being
submitted as a patch series. There should be about 26 patches by the
project's completion. Each patch will cleanup between 1 and 34 functions
apiece. Each patch covers a single file's functions.
This patch affects the following function(s):
1) csum_tree_block
2) csum_dirty_buffer
3) check_tree_block_fsid
4) btrfs_find_tree_block
5) clean_tree_block
Signed-off-by: Daniel Dressler <danieru.dressler@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
This is the second independent patch of a larger project to cleanup
btrfs's internal usage of btrfs_root. Many functions take btrfs_root
only to grab the fs_info struct.
By requiring a root these functions cause programmer overhead. That
these functions can accept any valid root is not obvious until
inspection.
This patch reduces the specificity of such functions to accept the
fs_info directly.
These patches can be applied independently and thus are not being
submitted as a patch series. There should be about 26 patches by the
project's completion. Each patch will cleanup between 1 and 34 functions
apiece. Each patch covers a single file's functions.
This patch affects the following function(s):
1) btrfs_wq_run_delayed_node
Signed-off-by: Daniel Dressler <danieru.dressler@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
This patch is part of a larger project to cleanup btrfs's internal usage
of struct btrfs_root. Many functions take btrfs_root only to grab a
pointer to fs_info.
This causes programmers to ponder which root can be passed. Since only
the fs_info is read affected functions can accept any root, except this
is only obvious upon inspection.
This patch reduces the specificty of such functions to accept the
fs_info directly.
This patch does not address the two functions in ctree.c (insert_ptr,
and split_item) which only use root for BUG_ONs in ctree.c
This patch affects the following functions:
1) fixup_low_keys
2) btrfs_set_item_key_safe
Signed-off-by: Daniel Dressler <danieru.dressler@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
If we are recording in the tree log that an inode has new names (new hard
links were added), we would drop items, belonging to the inode, that we
shouldn't:
1) When the flag BTRFS_INODE_COPY_EVERYTHING is set in the inode's runtime
flags, we ended up dropping all the extent and xattr items that were
previously logged. This was done only in memory, since logging a new
name doesn't imply syncing the log;
2) When the flag BTRFS_INODE_COPY_EVERYTHING is set in the inode's runtime
flags, we ended up dropping all the xattr items that were previously
logged. Like the case before, this was done only in memory because
logging a new name doesn't imply syncing the log.
This led to some surprises in scenarios such as the following:
1) write some extents to an inode;
2) fsync the inode;
3) truncate the inode or delete/modify some of its xattrs
4) add a new hard link for that inode
5) fsync some other file, to force the log tree to be durably persisted
6) power failure happens
The next time the fs is mounted, the fsync log replay code is executed,
and the resulting file doesn't have the content it had when the last fsync
against it was performed, instead if has a content matching what it had
when the last transaction commit happened.
So change the behaviour such that when a new name is logged, only the inode
item and reference items are processed.
This is easy to reproduce with the test I just made for xfstests, whose
main body is:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test file with some data.
$XFS_IO_PROG -f -c "pwrite -S 0xaa -b 8K 0 8K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Make sure the file is durably persisted.
sync
# Append some data to our file, to increase its size.
$XFS_IO_PROG -f -c "pwrite -S 0xcc -b 4K 8K 4K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Fsync the file, so from this point on if a crash/power failure happens, our
# new data is guaranteed to be there next time the fs is mounted.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Now shrink our file to 5000 bytes.
$XFS_IO_PROG -c "truncate 5000" $SCRATCH_MNT/foo
# Now do an expanding truncate to a size larger than what we had when we last
# fsync'ed our file. This is just to verify that after power failure and
# replaying the fsync log, our file matches what it was when we last fsync'ed
# it - 12Kb size, first 8Kb of data had a value of 0xaa and the last 4Kb of
# data had a value of 0xcc.
$XFS_IO_PROG -c "truncate 32K" $SCRATCH_MNT/foo
# Add one hard link to our file. This made btrfs drop all of our file's
# metadata from the fsync log, including the metadata relative to the
# extent we just wrote and fsync'ed. This change was made only to the fsync
# log in memory, so adding the hard link alone doesn't change the persisted
# fsync log. This happened because the previous truncates set the runtime
# flag BTRFS_INODE_NEEDS_FULL_SYNC in the btrfs inode structure.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link
# Now make sure the in memory fsync log is durably persisted.
# Creating and fsync'ing another file will do it.
# After this our persisted fsync log will no longer have metadata for our file
# foo that points to the extent we wrote and fsync'ed before.
touch $SCRATCH_MNT/bar
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/bar
# As expected, before the crash/power failure, we should be able to see a file
# with a size of 32Kb, with its first 5000 bytes having the value 0xaa and all
# the remaining bytes with value 0x00.
echo "File content before:"
od -t x1 $SCRATCH_MNT/foo
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# After mounting the fs again, the fsync log was replayed.
# The expected result is to see a file with a size of 12Kb, with its first 8Kb
# of data having the value 0xaa and its last 4Kb of data having a value of 0xcc.
# The btrfs bug used to leave the file as it used te be as of the last
# transaction commit - that is, with a size of 8Kb with all bytes having a
# value of 0xaa.
echo "File content after:"
od -t x1 $SCRATCH_MNT/foo
The test case for xfstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We have a scenario where after the fsync log replay we can lose file data
that had been previously fsync'ed if we added an hard link for our inode
and after that we sync'ed the fsync log (for example by fsync'ing some
other file or directory).
This is because when adding an hard link we updated the inode item in the
log tree with an i_size value of 0. At that point the new inode item was
in memory only and a subsequent fsync log replay would not make us lose
the file data. However if after adding the hard link we sync the log tree
to disk, by fsync'ing some other file or directory for example, we ended
up losing the file data after log replay, because the inode item in the
persisted log tree had an an i_size of zero.
This is easy to reproduce, and the following excerpt from my test for
xfstests shows this:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create one file with data and fsync it.
# This made the btrfs fsync log persist the data and the inode metadata with
# a correct inode->i_size (4096 bytes).
$XFS_IO_PROG -f -c "pwrite -S 0xaa -b 4K 0 4K" -c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Now add one hard link to our file. This made the btrfs code update the fsync
# log, in memory only, with an inode metadata having a size of 0.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link
# Now force persistence of the fsync log to disk, for example, by fsyncing some
# other file.
touch $SCRATCH_MNT/bar
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/bar
# Before a power loss or crash, we could read the 4Kb of data from our file as
# expected.
echo "File content before:"
od -t x1 $SCRATCH_MNT/foo
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# After the fsync log replay, because the fsync log had a value of 0 for our
# inode's i_size, we couldn't read anymore the 4Kb of data that we previously
# wrote and fsync'ed. The size of the file became 0 after the fsync log replay.
echo "File content after:"
od -t x1 $SCRATCH_MNT/foo
Another alternative test, that doesn't need to fsync an inode in the same
transaction it was created, is:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test file with some data.
$XFS_IO_PROG -f -c "pwrite -S 0xaa -b 8K 0 8K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Make sure the file is durably persisted.
sync
# Append some data to our file, to increase its size.
$XFS_IO_PROG -f -c "pwrite -S 0xcc -b 4K 8K 4K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Fsync the file, so from this point on if a crash/power failure happens, our
# new data is guaranteed to be there next time the fs is mounted.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Add one hard link to our file. This made btrfs write into the in memory fsync
# log a special inode with generation 0 and an i_size of 0 too. Note that this
# didn't update the inode in the fsync log on disk.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link
# Now make sure the in memory fsync log is durably persisted.
# Creating and fsync'ing another file will do it.
touch $SCRATCH_MNT/bar
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/bar
# As expected, before the crash/power failure, we should be able to read the
# 12Kb of file data.
echo "File content before:"
od -t x1 $SCRATCH_MNT/foo
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# After mounting the fs again, the fsync log was replayed.
# The btrfs fsync log replay code didn't update the i_size of the persisted
# inode because the inode item in the log had a special generation with a
# value of 0 (and it couldn't know the correct i_size, since that inode item
# had a 0 i_size too). This made the last 4Kb of file data inaccessible and
# effectively lost.
echo "File content after:"
od -t x1 $SCRATCH_MNT/foo
This isn't a new issue/regression. This problem has been around since the
log tree code was added in 2008:
Btrfs: Add a write ahead tree log to optimize synchronous operations
(commit e02119d5a7)
Test cases for xfstests follow soon.
CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
On our gluster boxes we stream large tar balls of backups onto our fses. With
160gb of ram this means we get really large contiguous ranges of dirty data, but
the way our ENOSPC stuff works is that as long as it's contiguous we only hold
metadata reservation for one extent. The problem is we limit our extents to
128mb, so we'll end up with at least 800 extents so our enospc accounting is
quite a bit lower than what we need. To keep track of this make sure we
increase outstanding_extents for every multiple of the max extent size so we can
be sure to have enough reserved metadata space. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
We do this to get the space accounting, but this is just needless churn on the
io_tree, so just drop setting/clearing delalloc and just drop the reserved data
space when we have a successfull allocation. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
We have this weird dance where we always inc outstanding_extents when we do a
O_DIRECT write, even if we allocate the entire range. To get around this we
also drop the metadata space if we successfully write. This is an unnecessary
dance, we only need to jack up outstanding_extents if we don't satisfy the
entire range request in get_blocks_direct, otherwise we are good using our
original reservation. So drop the unconditional inc and the drop of the
metadata space that we have for the unconditional inc. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Btrfs will report NO_SPACE when we create and remove files for several times,
and we can't write to filesystem until mount it again.
Steps to reproduce:
1: Create a single-dev btrfs fs with default option
2: Write a file into it to take up most fs space
3: Delete above file
4: Wait about 100s to let chunk removed
5: goto 2
Script is like following:
#!/bin/bash
# Recommend 1.2G space, too large disk will make test slow
DEV="/dev/sda16"
MNT="/mnt/tmp"
dev_size="$(lsblk -bn -o SIZE "$DEV")" || exit 2
file_size_m=$((dev_size * 75 / 100 / 1024 / 1024))
echo "Loop write ${file_size_m}M file on $((dev_size / 1024 / 1024))M dev"
for ((i = 0; i < 10; i++)); do umount "$MNT" 2>/dev/null; done
echo "mkfs $DEV"
mkfs.btrfs -f "$DEV" >/dev/null || exit 2
echo "mount $DEV $MNT"
mount "$DEV" "$MNT" || exit 2
for ((loop_i = 0; loop_i < 20; loop_i++)); do
echo
echo "loop $loop_i"
echo "dd file..."
cmd=(dd if=/dev/zero of="$MNT"/file0 bs=1M count="$file_size_m")
"${cmd[@]}" 2>/dev/null || {
# NO_SPACE error triggered
echo "dd failed: ${cmd[*]}"
exit 1
}
echo "rm file..."
rm -f "$MNT"/file0 || exit 2
for ((i = 0; i < 10; i++)); do
df "$MNT" | tail -1
sleep 10
done
done
Reason:
It is triggered by commit: 47ab2a6c68
which is used to remove empty block groups automatically, but the
reason is not in that patch. Code before works well because btrfs
don't need to create and delete chunks so many times with high
complexity.
Above bug is caused by many reason, any of them can trigger it.
Reason1:
When we remove some continuous chunks but leave other chunks after,
these disk space should be used by chunk-recreating, but in current
code, only first create will successed.
Fixed by Forrest Liu <forrestl@synology.com> in:
Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole
Reason2:
contains_pending_extent() return wrong value in calculation.
Fixed by Forrest Liu <forrestl@synology.com> in:
Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole
Reason3:
btrfs_check_data_free_space() try to commit transaction and retry
allocating chunk when the first allocating failed, but space_info->full
is set in first allocating, and prevent second allocating in retry.
Fixed in this patch by clear space_info->full in commit transaction.
Tested for severial times by above script.
Changelog v3->v4:
use light weight int instead of atomic_t to record have_remove_bgs in
transaction, suggested by:
Josef Bacik <jbacik@fb.com>
Changelog v2->v3:
v2 fixed the bug by adding more commit-transaction, but we
only need to reclaim space when we are really have no space for
new chunk, noticed by:
Filipe David Manana <fdmanana@gmail.com>
Actually, our code already have this type of commit-and-retry,
we only need to make it working with removed-bgs.
v3 fixed the bug with above way.
Changelog v1->v2:
v1 will introduce a new bug when delete and create chunk in same disk
space in same transaction, noticed by:
Filipe David Manana <fdmanana@gmail.com>
V2 fix this bug by commit transaction after remove block grops.
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Suggested-by: Filipe David Manana <fdmanana@gmail.com>
Suggested-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
My previous patch "Btrfs: fix scrub race leading to use-after-free"
introduced the possibility to sleep in an atomic context, which happens
when the scrub_lock mutex is held at the time scrub_pending_bio_dec()
is called - this function can be called under an atomic context.
Chris ran into this in a debug kernel which gave the following trace:
[ 1928.950319] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:621
[ 1928.967334] in_atomic(): 1, irqs_disabled(): 0, pid: 149670, name: fsstress
[ 1928.981324] INFO: lockdep is turned off.
[ 1928.989244] CPU: 24 PID: 149670 Comm: fsstress Tainted: G W 3.19.0-rc7-mason+ #41
[ 1929.006418] Hardware name: ZTSYSTEMS Echo Ridge T4 /A9DRPF-10D, BIOS 1.07 05/10/2012
[ 1929.022207] ffffffff81a22cf8 ffff881076e03b78 ffffffff816b8dd9 ffff881076e03b78
[ 1929.037267] ffff880d8e828710 ffff881076e03ba8 ffffffff810856c4 ffff881076e03bc8
[ 1929.052315] 0000000000000000 000000000000026d ffffffff81a22cf8 ffff881076e03bd8
[ 1929.067381] Call Trace:
[ 1929.072344] <IRQ> [<ffffffff816b8dd9>] dump_stack+0x4f/0x6e
[ 1929.083968] [<ffffffff810856c4>] ___might_sleep+0x174/0x230
[ 1929.095352] [<ffffffff810857d2>] __might_sleep+0x52/0x90
[ 1929.106223] [<ffffffff816bb68f>] mutex_lock_nested+0x2f/0x3b0
[ 1929.117951] [<ffffffff810ab37d>] ? trace_hardirqs_on+0xd/0x10
[ 1929.129708] [<ffffffffa05dc838>] scrub_pending_bio_dec+0x38/0x70 [btrfs]
[ 1929.143370] [<ffffffffa05dd0e0>] scrub_parity_bio_endio+0x50/0x70 [btrfs]
[ 1929.157191] [<ffffffff812fa603>] bio_endio+0x53/0xa0
[ 1929.167382] [<ffffffffa05f96bc>] rbio_orig_end_io+0x7c/0xa0 [btrfs]
[ 1929.180161] [<ffffffffa05f97ba>] raid_write_parity_end_io+0x5a/0x80 [btrfs]
[ 1929.194318] [<ffffffff812fa603>] bio_endio+0x53/0xa0
[ 1929.204496] [<ffffffff8130401b>] blk_update_request+0x1eb/0x450
[ 1929.216569] [<ffffffff81096e58>] ? trigger_load_balance+0x78/0x500
[ 1929.229176] [<ffffffff8144c74d>] scsi_end_request+0x3d/0x1f0
[ 1929.240740] [<ffffffff8144ccac>] scsi_io_completion+0xac/0x5b0
[ 1929.252654] [<ffffffff81441c50>] scsi_finish_command+0xf0/0x150
[ 1929.264725] [<ffffffff8144d317>] scsi_softirq_done+0x147/0x170
[ 1929.276635] [<ffffffff8130ace6>] blk_done_softirq+0x86/0xa0
[ 1929.288014] [<ffffffff8105d92e>] __do_softirq+0xde/0x600
[ 1929.298885] [<ffffffff8105df6d>] irq_exit+0xbd/0xd0
(...)
Fix this by using a reference count on the scrub context structure
instead of locking the scrub_lock mutex.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull backing device changes from Jens Axboe:
"This contains a cleanup of how the backing device is handled, in
preparation for a rework of the life time rules. In this part, the
most important change is to split the unrelated nommu mmap flags from
it, but also removing a backing_dev_info pointer from the
address_space (and inode), and a cleanup of other various minor bits.
Christoph did all the work here, I just fixed an oops with pages that
have a swap backing. Arnd fixed a missing export, and Oleg killed the
lustre backing_dev_info from staging. Last patch was from Al,
unexporting parts that are now no longer needed outside"
* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
Make super_blocks and sb_lock static
mtd: export new mtd_mmap_capabilities
fs: make inode_to_bdi() handle NULL inode
staging/lustre/llite: get rid of backing_dev_info
fs: remove default_backing_dev_info
fs: don't reassign dirty inodes to default_backing_dev_info
nfs: don't call bdi_unregister
ceph: remove call to bdi_unregister
fs: remove mapping->backing_dev_info
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
nilfs2: set up s_bdi like the generic mount_bdev code
block_dev: get bdev inode bdi directly from the block device
block_dev: only write bdev inode on close
fs: introduce f_op->mmap_capabilities for nommu mmap support
fs: kill BDI_CAP_SWAP_BACKED
fs: deduplicate noop_backing_dev_info
Helper account_page_redirty() fixes dirty pages counter for redirtied
pages. This patch puts it after dirtying and prevents temporary
underflows of dirtied pages counters on zone/bdi and current->nr_dirtied.
Signed-off-by: Konstantin Khebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull RCU updates from Ingo Molnar:
"The main RCU changes in this cycle are:
- Documentation updates.
- Miscellaneous fixes.
- Preemptible-RCU fixes, including fixing an old bug in the
interaction of RCU priority boosting and CPU hotplug.
- SRCU updates.
- RCU CPU stall-warning updates.
- RCU torture-test updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
rcu: Initialize tiny RCU stall-warning timeouts at boot
rcu: Fix RCU CPU stall detection in tiny implementation
rcu: Add GP-kthread-starvation checks to CPU stall warnings
rcu: Make cond_resched_rcu_qs() apply to normal RCU flavors
rcu: Optionally run grace-period kthreads at real-time priority
ksoftirqd: Use new cond_resched_rcu_qs() function
ksoftirqd: Enable IRQs and call cond_resched() before poking RCU
rcutorture: Add more diagnostics in rcu_barrier() test failure case
torture: Flag console.log file to prevent holdovers from earlier runs
torture: Add "-enable-kvm -soundhw pcspk" to qemu command line
rcutorture: Handle different mpstat versions
rcutorture: Check from beginning to end of grace period
rcu: Remove redundant rcu_batches_completed() declaration
rcutorture: Drop rcu_torture_completed() and friends
rcu: Provide rcu_batches_completed_sched() for TINY_RCU
rcutorture: Use unsigned for Reader Batch computations
rcutorture: Make build-output parsing correctly flag RCU's warnings
rcu: Make _batches_completed() functions return unsigned long
rcutorture: Issue warnings on close calls due to Reader Batch blows
documentation: Fix smp typo in memory-barriers.txt
...
Pull btrfs fix from Chris Mason:
"Forrest Liu tracked down a missing blk_finish_plug in the btrfs
logging code. This isn't a new bug, and it's hard to hit. But, it's
safe enough for inclusion now, and in my for-linus branch"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: add missing blk_finish_plug in btrfs_sync_log()
Add missing blk_finish_plug in btrfs_sync_log()
Signed-off-by: Forrest Liu <forrestl@synology.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
o removed an unecessary INIT_LIST_HEAD after LIST_HEAD
o merge a declare & INIT_LIST_HEAD pair into one LIST_HEAD
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Below test will fail currently:
mkfs.ext4 -F /dev/sda
btrfs-convert /dev/sda
mount /dev/sda /mnt
btrfs device add -f /dev/sdb /mnt
btrfs balance start -v -dconvert=raid1 -mconvert=raid1 /mnt
The reason is there are some block groups with usage 0, but the whole
disk hasn't free space to allocate new chunk, so we even can't set such
block group readonly. This patch deletes the chunk allocation when
setting block group ro. For META, we already have reserve. But for
SYSTEM, we don't have, so the check_system_chunk is still required.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Verify that the sys_array has enough bytes to read the next item.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
There's a pointer to buffer, integer offset and offset passed as
pointer, try to find matching names for them.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Verify that possible minimum and maximum size is set, validity of
contents is checked in btrfs_read_sys_array.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
I received a few crafted images from Jiri, all got through the recently
added superblock checks. The lower bounds checks for num_devices and
sector/node -sizes were missing and caused a crash during mount.
Tools for symbolic code execution were used to prepare the images
contents.
Reported-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
This patch adds a new member to the 'struct btrfs_inode' structure to hold
the file creation time.
Signed-off-by: chandan <chandanrmail@gmail.com>
[refreshed, removed btrfs_inode_otime]
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fix from Chris Mason:
"We have one more fix for btrfs in my for-linus branch - this was a bug
in the new raid5/6 scrubbing support"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix raid56 scrub failed in xfstests btrfs/072
The xfstests btrfs/072 reports uncorrectable read errors in dmesg,
because scrub forgets to use commit_root for parity scrub routine
and scrub attempts to scrub those extents items whose contents are
not fully on disk.
To fix it, we just add the @search_commit_root flag back.
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"We have a few fixes in my for-linus branch.
Qu Wenruo's batch fix a regression between some our merge window pull
and the inode_cache feature. The rest are smaller bugs"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: Don't call btrfs_start_transaction() on frozen fs to avoid deadlock.
btrfs: Fix the bug that fs_info->pending_changes is never cleared.
btrfs: fix state->private cast on 32 bit machines
Btrfs: fix race deleting block group from space_info->ro_bgs list
Btrfs: fix incorrect freeing in scrub_stripe
btrfs: sync ioctl, handle errors after transaction start
btrfs_alloc_tree_block() returns an extent buffer on which a blocked lock has
been taken. Hence assign the appropriate value to path->locks[level].
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Chris Mason <clm@fb.com>
There isn't any real use of following members of struct btrfs_root
so delete them.
struct kobject root_kobj;
struct completion kobj_unregister;
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
In function qgroup_excl_accounting(), we need to WARN when
qg->excl is less than what we want to free, same to child
and parents. But currently, for parent qgroup, the WARN_ON()
is located after freeing qg->excl. It will WARN out even we
free it normally.
This patch move this WARN_ON() before freeing qg->excl.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
"run_most" is not used anymore.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
refs is better than ref_count to record a struct's ref count.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Suggested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
So we can check raid56 with:
(map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
instead of long:
(map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Corrent code use many kinds of "clever" way to determine operation
target's raid type, as:
raid_map != NULL
or
raid_map[MAX_NR] == RAID[56]_Q_STRIPE
To make code easy to maintenance, this patch put raid type into
bbio, and we can always get raid type from bbio with a "stupid"
way.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
scrub_setup_recheck_block() have many arguments but most of them
can be get from one of them, we can remove them to make code clean.
Some other cleanup for that function also included in this patch.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The code are similar, combine them to make code clean and easy to maintenance.
Some lost condition are also completed with benefit of this combination.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
In corrent code, code of finding-right-mirror and writing-to-target
are mixed in logic, if we find a right mirror but failed in writing
to target, it will treat as "hadn't found right block", and fill the
target with sblock_bad.
Actually, "failed in writing to target" does not mean "source
block is wrong", this patch separate above two condition in logic,
and do some cleanup to make code clean.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Use break instead of useless loop should be more suitable in this
case.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
1: Remove no-need DEFINE_WAIT(wait)
2: Add likely() for BTRFS_FS_STATE_DEV_REPLACING condition
3: Use while loop instead of goto
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
It is always 1 in this place, because !1 case was already jumped
out in previous code.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
if (sctx->is_dev_replace && !is_metadata && !have_csum) {
...
goto nodatasum_case;
}
...
nodatasum_case:
WARN_ON(sctx->is_dev_replace);
In above code, nodatasum_case marker should be moved after
WARN_ON().
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
1: ref_count is simple than current RBIO_HOLD_BBIO_MAP_BIT flag
to keep btrfs_bio's memory in raid56 recovery implement.
2: free function for bbio will make code clean and flexible, plus
forced data type checking in compile.
Changelog v1->v2:
Rename following by David Sterba's suggestion:
put_btrfs_bio() -> btrfs_put_bio()
get_btrfs_bio() -> btrfs_get_bio()
bbio->ref_count -> bbio->refs
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
It can make code more simple and clear, we need not care about
free bbio and raid_map together.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
It can avoid complex calculation of real stripes in sort,
moreover, we can clean up code of sorting tgtdev_map because it
will be in order initially.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We add the number of stripes on target devices into bbio->num_stripes
if we are under device replacement, and we just sort the raid_map of
those stripes that not on the target devices, so if when we need
real raid_map, we need skip the stripes on the target devices.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we have an inode with a large number of hard links, some of which may
be extrefs, turn a regular ref into an extref, fsync the inode and then
replay the fsync log (after a crash/reboot), we can endup with an fsync
log that makes the replay code always fail with -EOVERFLOW when processing
the inode's references.
This is easy to reproduce with the test case I made for xfstests. Its steps
are the following:
_scratch_mkfs "-O extref" >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create a test file with 3001 hard links. This number is large enough to
# make btrfs start using extrefs at some point even if the fs has the maximum
# possible leaf/node size (64Kb).
echo "hello world" > $SCRATCH_MNT/foo
for i in `seq 1 3000`; do
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link_`printf "%04d" $i`
done
# Make sure all metadata and data are durably persisted.
sync
# Now remove one link, add a new one with a new name, add another new one with
# the same name as the one we just removed and fsync the inode.
rm -f $SCRATCH_MNT/foo_link_0001
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link_3001
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link_0001
rm -f $SCRATCH_MNT/foo_link_0002
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link_3002
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link_3003
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Simulate a crash/power loss. This makes sure the next mount
# will see an fsync log and will replay that log.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Check that the number of hard links is correct, we are able to remove all
# the hard links and read the file's data. This is just to verify we don't
# get stale file handle errors (due to dangling directory index entries that
# point to inodes that no longer exist).
echo "Link count: $(stat --format=%h $SCRATCH_MNT/foo)"
[ -f $SCRATCH_MNT/foo ] || echo "Link foo is missing"
for ((i = 1; i <= 3003; i++)); do
name=foo_link_`printf "%04d" $i`
if [ $i -eq 2 ]; then
[ -f $SCRATCH_MNT/$name ] && echo "Link $name found"
else
[ -f $SCRATCH_MNT/$name ] || echo "Link $name is missing"
fi
done
rm -f $SCRATCH_MNT/foo_link_*
cat $SCRATCH_MNT/foo
rm -f $SCRATCH_MNT/foo
status=0
exit
The fix is simply to correct the overflow condition when overwriting a
reference item because it was wrong, trying to increase the item in the
fs/subvol tree by an impossible amount. Also ensure that we don't insert
one normal ref and one ext ref for the same dentry - this happened because
processing a dir index entry from the parent in the log happened when
the normal ref item was full, which made the logic insert an extref and
later when the normal ref had enough room, it would be inserted again
when processing the ref item from the child inode in the log.
This issue has been present since the introduction of the extrefs feature
(2012).
A test case for xfstests follows soon. This test only passes if the previous
patch titled "Btrfs: fix fsync when extend references are added to an inode"
is applied too.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we added an extended reference to an inode and fsync'ed it, the log
replay code would make our inode have an incorrect link count, which
was lower then the expected/correct count.
This resulted in stale directory index entries after deleting some of
the hard links, and any access to the dangling directory entries resulted
in -ESTALE errors because the entries pointed to inode items that don't
exist anymore.
This is easy to reproduce with the test case I made for xfstests, and
the bulk of that test is:
_scratch_mkfs "-O extref" >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create a test file with 3001 hard links. This number is large enough to
# make btrfs start using extrefs at some point even if the fs has the maximum
# possible leaf/node size (64Kb).
echo "hello world" > $SCRATCH_MNT/foo
for i in `seq 1 3000`; do
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link_`printf "%04d" $i`
done
# Make sure all metadata and data are durably persisted.
sync
# Add one more link to the inode that ends up being a btrfs extref and fsync
# the inode.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/foo_link_3001
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Simulate a crash/power loss. This makes sure the next mount
# will see an fsync log and will replay that log.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Now after the fsync log replay btrfs left our inode with a wrong link count N,
# which was smaller than the correct link count M (N < M).
# So after removing N hard links, the remaining M - N directory entries were
# still visible to user space but it was impossible to do anything with them
# because they pointed to an inode that didn't exist anymore. This resulted in
# stale file handle errors (-ESTALE) when accessing those dentries for example.
#
# So remove all hard links except the first one and then attempt to read the
# file, to verify we don't get an -ESTALE error when accessing the inodel
#
# The btrfs fsck tool also detected the incorrect inode link count and it
# reported an error message like the following:
#
# root 5 inode 257 errors 2001, no inode item, link count wrong
# unresolved ref dir 256 index 2978 namelen 13 name foo_link_2976 filetype 1 errors 4, no inode ref
#
# The fstests framework automatically calls fsck after a test is run, so we
# don't need to call fsck explicitly here.
rm -f $SCRATCH_MNT/foo_link_*
cat $SCRATCH_MNT/foo
status=0
exit
So make sure an fsync always flushes the delayed inode item, so that the
fsync log contains it (needed in order to trigger the link count fixup
code) and fix the extref counting function, which always return -ENOENT
to its caller (and made it assume there were always 0 extrefs).
This issue has been present since the introduction of the extrefs feature
(2012).
A test case for xfstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we have an inode (file) with a link count greater than 1, remove
one of its hard links, fsync the inode, power fail/crash and then
replay the fsync log on the next mount, we end up getting the parent
directory's metadata inconsistent - its i_size still reflects the
deleted hard link and has dangling index entries (with no matching
inode reference entries). This prevents the directory from ever being
deletable, as its i_size can never decrease to BTRFS_EMPTY_DIR_SIZE
even if all of its children inodes are deleted, and the dangling index
entries can never be removed (as they point to an inode that does not
exist anymore).
This is easy to reproduce with the following excerpt from the test case
for xfstests that I just made:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create a test file with 2 hard links in the same directory.
mkdir -p $SCRATCH_MNT/a/b
echo "hello world" > $SCRATCH_MNT/a/b/foo
ln $SCRATCH_MNT/a/b/foo $SCRATCH_MNT/a/b/bar
# Make sure all metadata and data are durably persisted.
sync
# Now remove one of the hard links and fsync the inode.
rm -f $SCRATCH_MNT/a/b/bar
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/a/b/foo
# Simulate a crash/power loss. This makes sure the next mount
# will see an fsync log and will replay that log.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Remove the last hard link of the file and attempt to remove its parent
# directory - this failed in btrfs because the fsync log and replay code
# didn't decrement the parent directory's i_size and left dangling directory
# index entries - this made the btrfs rmdir implementation always fail with
# the error -ENOTEMPTY.
#
# The dangling directory index entries were visible to user space, but it was
# impossible to do anything on them (unlink, open, read, write, stat, etc)
# because the inode they pointed to did not exist anymore.
#
# The parent directory's metadata inconsistency (stale index entries) was
# also detected by btrfs' fsck tool, which is run automatically by the fstests
# framework when the test finishes. The error message reported by fsck was:
#
# root 5 inode 259 errors 2001, no inode item, link count wrong
# unresolved ref dir 258 index 3 namelen 3 name bar filetype 1 errors 4, no inode ref
#
rm -f $SCRATCH_MNT/a/b/*
rmdir $SCRATCH_MNT/a/b
rmdir $SCRATCH_MNT/a
To fix this just make sure that after an unlink, if the inode is fsync'ed,
he parent inode is fully logged in the fsync log.
A test case for xfstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Very often our extent buffer's header generation doesn't match the current
transaction's id or it is also referenced by other trees (snapshots), so
we don't need the corresponding block group cache object. Therefore only
search for it if we are going to use it, so we avoid an unnecessary search
in the block groups rbtree (and acquiring and releasing its spinlock).
Freeing a tree block is performed when COWing or deleting a node/leaf,
which implies we are holding the node/leaf's parent node lock, therefore
reducing the amount of time spent when freeing a tree block helps reducing
the amount of time we are holding the parent node's lock.
For example, for a run of xfstests/generic/083, the block group cache
object was needed only 682 times for a total of 226691 calls to free
a tree block.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently there's a 4B hole in the structure between refs and state and there
are only 16 bits used so we can make it unsigned. This will get a better
packing and may save some stack space for local variables.
The size of extent_state gets reduced by 8B and there are usually a lot
of slab objects.
struct extent_state {
u64 start; /* 0 8 */
u64 end; /* 8 8 */
struct rb_node rb_node; /* 16 24 */
wait_queue_head_t wq; /* 40 24 */
/* --- cacheline 1 boundary (64 bytes) --- */
atomic_t refs; /* 64 4 */
/* XXX 4 bytes hole, try to pack */
long unsigned int state; /* 72 8 */
u64 private; /* 80 8 */
/* size: 88, cachelines: 2, members: 7 */
/* sum members: 84, holes: 1, sum holes: 4 */
/* last cacheline: 24 bytes */
};
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
This has been confusing people for too long, the message is really just
informative.
CC: <stable@vger.kernel.org> # 3.10+
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The errors are worth noting and might get missed with INFO level.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
All error conditions from open_ctree shall be ERR. Warning would
suggest that something's wrong and we can continue.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Several messages that point to some internal problem, level INFO is
wrong here.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
We were incorrectly detecting when the target key didn't exist anymore
after releasing the path and re-searching the tree. This could make
us split or duplicate (btrfs_split_item() and btrfs_duplicate_item()
are its only callers at the moment) an item when we should not.
For the case of duplicating an item, we currently only duplicate
checksum items (csum tree) and file extent items (fs/subvol trees).
For the checksum items we end up overriding the item completely,
but for file extent items we update only some of their fields in
the copy (done in __btrfs_drop_extents), which means we can end up
having a logical corruption for some values.
Also for the case where we duplicate a file extent item it will make
us produce a leaf with a wrong key order, as btrfs_duplicate_item()
advances us to the next slot and then its caller sets a smaller key
on the new item at that slot (like in __btrfs_drop_extents() e.g.).
Alternatively if the tree search in setup_leaf_for_split() leaves
with path->slots[0] == btrfs_header_nritems(path->nodes[0]), we end
up accessing beyond the leaf's end (when we check if the item's size
has changed) and make our caller insert an item at the invalid slot
btrfs_header_nritems(path->nodes[0]) + 1, causing an invalid memory
access if the leaf is full or nearly full.
This issue has been present since the introduction of this function
in 2009:
Btrfs: Add btrfs_duplicate_item
commit ad48fd7546
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently any time we try to update the block groups on disk we will walk _all_
block groups and check for the ->dirty flag to see if it is set. This function
can get called several times during a commit. So if you have several terabytes
of data you will be a very sad panda as we will loop through _all_ of the block
groups several times, which makes the commit take a while which slows down the
rest of the file system operations.
This patch introduces a dirty list for the block groups that we get added to
when we dirty the block group for the first time. Then we simply update any
block groups that have been dirtied since the last time we called
btrfs_write_dirty_block_groups. This allows us to clean up how we write the
free space cache out so it is much cleaner. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
I've been overloading root->dirty_list to keep track of dirty roots and which
roots need to have their commit roots switched at transaction commit time. This
could cause us to lose an update to the root which could corrupt the file
system. To fix this use a state bit to know if the root is dirty, and if it
isn't set we go ahead and move the root to the dirty list. This way if we
re-dirty the root after adding it to the switch_commit list we make sure to
update it. This also makes it so that the extent root is always the last root
on the dirty list to try and keep the amount of churn down at this point in the
commit. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull RCU updates from Paul E. McKenney:
- Documentation updates.
- Miscellaneous fixes.
- Preemptible-RCU fixes, including fixing an old bug in the
interaction of RCU priority boosting and CPU hotplug.
- SRCU updates.
- RCU CPU stall-warning updates.
- RCU torture-test updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 6b5fe46dfa (btrfs: do commit in sync_fs if there are pending
changes) will call btrfs_start_transaction() in sync_fs(), to handle
some operations needed to be done in next transaction.
However this can cause deadlock if the filesystem is frozen, with the
following sys_r+w output:
[ 143.255932] Call Trace:
[ 143.255936] [<ffffffff816c0e09>] schedule+0x29/0x70
[ 143.255939] [<ffffffff811cb7f3>] __sb_start_write+0xb3/0x100
[ 143.255971] [<ffffffffa040ec06>] start_transaction+0x2e6/0x5a0
[btrfs]
[ 143.255992] [<ffffffffa040f1eb>] btrfs_start_transaction+0x1b/0x20
[btrfs]
[ 143.256003] [<ffffffffa03dc0ba>] btrfs_sync_fs+0xca/0xd0 [btrfs]
[ 143.256007] [<ffffffff811f7be0>] sync_fs_one_sb+0x20/0x30
[ 143.256011] [<ffffffff811cbd01>] iterate_supers+0xe1/0xf0
[ 143.256014] [<ffffffff811f7d75>] sys_sync+0x55/0x90
[ 143.256017] [<ffffffff816c49d2>] system_call_fastpath+0x12/0x17
[ 143.256111] Call Trace:
[ 143.256114] [<ffffffff816c0e09>] schedule+0x29/0x70
[ 143.256119] [<ffffffff816c3405>] rwsem_down_write_failed+0x1c5/0x2d0
[ 143.256123] [<ffffffff8133f013>] call_rwsem_down_write_failed+0x13/0x20
[ 143.256131] [<ffffffff811caae8>] thaw_super+0x28/0xc0
[ 143.256135] [<ffffffff811db3e5>] do_vfs_ioctl+0x3f5/0x540
[ 143.256187] [<ffffffff811db5c1>] SyS_ioctl+0x91/0xb0
[ 143.256213] [<ffffffff816c49d2>] system_call_fastpath+0x12/0x17
The reason is like the following:
(Holding s_umount)
VFS sync_fs staff:
|- btrfs_sync_fs()
|- btrfs_start_transaction()
|- sb_start_intwrite()
(Waiting thaw_fs to unfreeze)
VFS thaw_fs staff:
thaw_fs()
(Waiting sync_fs to release
s_umount)
So deadlock happens.
This can be easily triggered by fstest/generic/068 with inode_cache
mount option.
The fix is to check if the fs is frozen, if the fs is frozen, just
return and waiting for the next transaction.
Cc: David Sterba <dsterba@suse.cz>
Reported-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
[enhanced comment, changed to SB_FREEZE_WRITE]
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Fs_info->pending_changes is never cleared since the original code uses
cmpxchg(&fs_info->pending_changes, 0, 0), which will only clear it if
pending_changes is already 0.
This will cause a lot of problem when mount it with inode_cache mount
option.
If the btrfs is mounted as inode_cache, pending_changes will always be
1, even when the fs is frozen.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Now that default_backing_dev_info is not used for writeback purposes we can
git rid of it easily:
- instead of using it's name for tracing unregistered bdi we just use
"unknown"
- btrfs and ceph can just assign the default read ahead window themselves
like several other filesystems already do.
- we can assign noop_backing_dev_info as the default one in alloc_super.
All filesystems already either assigned their own or
noop_backing_dev_info.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Now that we got rid of the bdi abuse on character devices we can always use
sb->s_bdi to get at the backing_dev_info for a file, except for the block
device special case. Export inode_to_bdi and replace uses of
mapping->backing_dev_info with it to prepare for the removal of
mapping->backing_dev_info.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.
Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead. Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device. It also removes the need for
the mtd_inodefs filesystem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Suppress the following warning displayed on building 32bit (i686) kernel.
===============================================================================
...
CC [M] fs/btrfs/extent_io.o
fs/btrfs/extent_io.c: In function ‘btrfs_free_io_failure_record’:
fs/btrfs/extent_io.c:2193:13: warning: cast to pointer from integer of
different size [-Wint-to-pointer-cast]
failrec = (struct io_failure_record *)state->private;
...
===============================================================================
Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Reported-by: Chris Murphy <chris@colorremedies.com>
Signed-off-by: Chris Mason <clm@fb.com>
When removing a block group we were deleting it from its space_info's
ro_bgs list without the correct protection - the space info's spinlock.
Fix this by doing the list delete while holding the spinlock of the
corresponding space info, which is the correct lock for any operation
on that list.
This issue was introduced in the 3.19 kernel by the following change:
Btrfs: move read only block groups onto their own list V2
commit 633c0aad4c
I ran into a kernel crash while a task was running statfs, which iterates
the space_info->ro_bgs list while holding the space info's spinlock,
and another task was deleting it from the same list, without holding that
spinlock, as part of the block group remove operation (while running the
function btrfs_remove_block_group). This happened often when running the
stress test xfstests/generic/038 I recently made.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The address that should be freed is not 'ppath' but 'path'.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Reviewed-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>
The version merged to 3.19 did not handle errors from start_trancaction
and could pass an invalid pointer to commit_transaction.
Fixes: 6b5fe46dfa ("btrfs: do commit in sync_fs if there are pending changes")
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
If the found_key is NULL, then btrfs_find_item becomes a verbose wrapper
for simple btrfs_search_slot.
After we've removed all such callers, passing a NULL key is not valid
anymore.
Signed-off-by: David Sterba <dsterba@suse.cz>
We can search and add the orphan item in one go,
btrfs_insert_orphan_item will find out if the item already exists.
Signed-off-by: David Sterba <dsterba@suse.cz>
If btrfs_find_item is called with NULL path it allocates one locally but
does not free it. Affected paths are inserting an orphan item for a file
and for a subvol root.
Move the path allocation to the callers.
CC: <stable@vger.kernel.org> # 3.14+
Fixes: 3f870c2899 ("btrfs: expand btrfs_find_item() to include find_orphan_item functionality")
Signed-off-by: David Sterba <dsterba@suse.cz>
Pull btrfs fixes from Chris Mason:
"None of these are huge, but my commit does fix a regression from 3.18
that could cause lost files during log replay.
This also adds Dave Sterba to the list of Btrfs maintainers. It
doesn't mean we're doing things differently, but Dave has really been
helping with the maintainer workload for years"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: don't delay inode ref updates during log replay
Btrfs: correctly get tree level in tree_backref_for_extent
Btrfs: call inode_dec_link_count() on mkdir error path
Btrfs: abort transaction if we don't find the block group
Btrfs, scrub: uninitialized variable in scrub_extent_for_parity()
Btrfs: add more maintainers
SRCU is not necessary to be compiled by default in all cases. For tinification
efforts not compiling SRCU unless necessary is desirable.
The current patch tries to make compiling SRCU optional by introducing a new
Kconfig option CONFIG_SRCU which is selected when any of the components making
use of SRCU are selected.
If we do not select CONFIG_SRCU, srcu.o will not be compiled at all.
text data bss dec hex filename
2007 0 0 2007 7d7 kernel/rcu/srcu.o
Size of arch/powerpc/boot/zImage changes from
text data bss dec hex filename
831552 64180 23944 919676 e087c arch/powerpc/boot/zImage : before
829504 64180 23952 917636 e0084 arch/powerpc/boot/zImage : after
so the savings are about ~2000 bytes.
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: resolve conflict due to removal of arch/ia64/kvm/Kconfig. ]
Commit 1d52c78afb (Btrfs: try not to ENOSPC on log replay) added a
check to skip delayed inode updates during log replay because it
confuses the enospc code. But the delayed processing will end up
ignoring delayed refs from log replay because the inode itself wasn't
put through the delayed code.
This can end up triggering a warning at commit time:
WARNING: CPU: 2 PID: 778 at fs/btrfs/delayed-inode.c:1410 btrfs_assert_delayed_root_empty+0x32/0x34()
Which is repeated for each commit because we never process the delayed
inode ref update.
The fix used here is to change btrfs_delayed_delete_inode_ref to return
an error if we're currently in log replay. The caller will do the ref
deletion immediately and everything will work properly.
Signed-off-by: Chris Mason <clm@fb.com>
cc: stable@vger.kernel.org # v3.18 and any stable series that picked 1d52c78afb
If we are using skinny metadata, the block's tree level is in the offset
of the key and not in a btrfs_tree_block_info structure following the
extent item (it doesn't exist). Therefore fix it.
Besides returning the correct level in the tree, this also prevents reading
past the leaf's end in the case where the extent item is the last item in
the leaf (eb) and it has only 1 inline reference - this is because
sizeof(struct btrfs_tree_block_info) is greater than
sizeof(struct btrfs_extent_inline_ref).
Got it while running a scrub which produced the following warning:
BTRFS: checksum error at logical 42123264 on dev /dev/sde, sector 15840: metadata node (level 24) in tree 5
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
In btrfs_mkdir(), if it fails to create dir, we should
clean up existed items, setting inode's link properly
to make sure it could be cleaned up properly.
Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
We shouldn't BUG_ON() if there is corruption. I hit this while testing my block
group patch and the abort worked properly. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The only way that "ret" is set is when we call scrub_pages_for_parity()
so the skip to "if (ret) " test doesn't make sense and causes a static
checker warning.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull vfs pile #3 from Al Viro:
"Assorted fixes and patches from the last cycle"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
[regression] chunk lost from bd9b51
vfs: make mounts and mountstats honor root dir like mountinfo does
vfs: cleanup show_mountinfo
init: fix read-write root mount
unfuck binfmt_misc.c (broken by commit e6084d4)
vm_area_operations: kill ->migrate()
new helper: iter_is_iovec()
move_extent_per_page(): get rid of unused w_flags
lustre: get rid of playing with ->fs
btrfs: filp_open() returns ERR_PTR() on failure, not NULL...
Pull more btrfs updates from Chris Mason:
"This is part two of our merge window patches.
These are all from Filipe, and fix some really hard to find races that
can cause corruptions. Most of them involved block group removal
(balance) or discard"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: remove non-sense btrfs_error_discard_extent() function
Btrfs: fix fs corruption on transaction abort if device supports discard
Btrfs: always clear a block group node when removing it from the tree
Btrfs: ensure deletion from pinned_chunks list is protected
Pull btrfs update from Chris Mason:
"From a feature point of view, most of the code here comes from Miao
Xie and others at Fujitsu to implement scrubbing and replacing devices
on raid56. This has been in development for a while, and it's a big
improvement.
Filipe and Josef have a great assortment of fixes, many of which solve
problems corruptions either after a crash or in error conditions. I
still have a round two from Filipe for next week that solves
corruptions with discard and block group removal"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (62 commits)
Btrfs: make get_caching_control unconditionally return the ctl
Btrfs: fix unprotected deletion from pending_chunks list
Btrfs: fix fs mapping extent map leak
Btrfs: fix memory leak after block remove + trimming
Btrfs: make btrfs_abort_transaction consider existence of new block groups
Btrfs: fix race between writing free space cache and trimming
Btrfs: fix race between fs trimming and block group remove/allocation
Btrfs, replace: enable dev-replace for raid56
Btrfs: fix freeing used extents after removing empty block group
Btrfs: fix crash caused by block group removal
Btrfs: fix invalid block group rbtree access after bg is removed
Btrfs, raid56: fix use-after-free problem in the final device replace procedure on raid56
Btrfs, replace: write raid56 parity into the replace target device
Btrfs, replace: write dirty pages into the replace target device
Btrfs, raid56: support parity scrub on raid56
Btrfs, raid56: use a variant to record the operation type
Btrfs, scrub: repair the common data on RAID5/6 if it is corrupted
Btrfs, raid56: don't change bbio and raid_map
Btrfs: remove unnecessary code of stripe_index assignment in __btrfs_map_block
Btrfs: remove noused bbio_ret in __btrfs_map_block in condition
...
Make the extent buffer allocation interface consistent. Cloned eb will
set a valid fs_info. For dummy eb, we can drop the length parameter and
set it from fs_info.
The built-in sanity checks may pass a NULL fs_info that's queried for
nodesize, but we know it's 4096.
Signed-off-by: David Sterba <dsterba@suse.cz>
Finally it's clear that the requested blocksize is always equal to
nodesize, with one exception, the superblock.
Superblock has fixed size regardless of the metadata block size, but
uses the same helpers to initialize sys array/chunk tree and to work
with the chunk items. So it pretends to be an extent_buffer for a
moment, btrfs_read_sys_array is full of special cases, we're adding one
more.
Signed-off-by: David Sterba <dsterba@suse.cz>
Pull VFS changes from Al Viro:
"First pile out of several (there _definitely_ will be more). Stuff in
this one:
- unification of d_splice_alias()/d_materialize_unique()
- iov_iter rewrite
- killing a bunch of ->f_path.dentry users (and f_dentry macro).
Getting that completed will make life much simpler for
unionmount/overlayfs, since then we'll be able to limit the places
sensitive to file _dentry_ to reasonably few. Which allows to have
file_inode(file) pointing to inode in a covered layer, with dentry
pointing to (negative) dentry in union one.
Still not complete, but much closer now.
- crapectomy in lustre (dead code removal, mostly)
- "let's make seq_printf return nothing" preparations
- assorted cleanups and fixes
There _definitely_ will be more piles"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
copy_from_iter_nocache()
new helper: iov_iter_kvec()
csum_and_copy_..._iter()
iov_iter.c: handle ITER_KVEC directly
iov_iter.c: convert copy_to_iter() to iterate_and_advance
iov_iter.c: convert copy_from_iter() to iterate_and_advance
iov_iter.c: get rid of bvec_copy_page_{to,from}_iter()
iov_iter.c: convert iov_iter_zero() to iterate_and_advance
iov_iter.c: convert iov_iter_get_pages_alloc() to iterate_all_kinds
iov_iter.c: convert iov_iter_get_pages() to iterate_all_kinds
iov_iter.c: convert iov_iter_npages() to iterate_all_kinds
iov_iter.c: iterate_and_advance
iov_iter.c: macros for iterating over iov_iter
kill f_dentry macro
dcache: fix kmemcheck warning in switch_names
new helper: audit_file()
nfsd_vfs_write(): use file_inode()
ncpfs: use file_inode()
kill f_dentry uses
lockd: get rid of ->f_path.dentry->d_sb
...
It doesn't do anything special, it just calls btrfs_discard_extent(),
so just remove it.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we abort a transaction we iterate over all the ranges marked as dirty
in fs_info->freed_extents[0] and fs_info->freed_extents[1], clear them
from those trees, add them back (unpin) to the free space caches and, if
the fs was mounted with "-o discard", perform a discard on those regions.
Also, after adding the regions to the free space caches, a fitrim ioctl call
can see those ranges in a block group's free space cache and perform a discard
on the ranges, so the same issue can happen without "-o discard" as well.
This causes corruption, affecting one or multiple btree nodes (in the worst
case leaving the fs unmountable) because some of those ranges (the ones in
the fs_info->pinned_extents tree) correspond to btree nodes/leafs that are
referred by the last committed super block - breaking the rule that anything
that was committed by a transaction is untouched until the next transaction
commits successfully.
I ran into this while running in a loop (for several hours) the fstest that
I recently submitted:
[PATCH] fstests: add btrfs test to stress chunk allocation/removal and fstrim
The corruption always happened when a transaction aborted and then fsck complained
like this:
_check_btrfs_filesystem: filesystem on /dev/sdc is inconsistent
*** fsck.btrfs output ***
Check tree block failed, want=94945280, have=0
Check tree block failed, want=94945280, have=0
Check tree block failed, want=94945280, have=0
Check tree block failed, want=94945280, have=0
Check tree block failed, want=94945280, have=0
read block failed check_tree_block
Couldn't open file system
In this case 94945280 corresponded to the root of a tree.
Using frace what I observed was the following sequence of steps happened:
1) transaction N started, fs_info->pinned_extents pointed to
fs_info->freed_extents[0];
2) node/eb 94945280 is created;
3) eb is persisted to disk;
4) transaction N commit starts, fs_info->pinned_extents now points to
fs_info->freed_extents[1], and transaction N completes;
5) transaction N + 1 starts;
6) eb is COWed, and btrfs_free_tree_block() called for this eb;
7) eb range (94945280 to 94945280 + 16Kb) is added to
fs_info->pinned_extents (fs_info->freed_extents[1]);
8) Something goes wrong in transaction N + 1, like hitting ENOSPC
for example, and the transaction is aborted, turning the fs into
readonly mode. The stack trace I got for example:
[112065.253935] [<ffffffff8140c7b6>] dump_stack+0x4d/0x66
[112065.254271] [<ffffffff81042984>] warn_slowpath_common+0x7f/0x98
[112065.254567] [<ffffffffa0325990>] ? __btrfs_abort_transaction+0x50/0x10b [btrfs]
[112065.261674] [<ffffffff810429e5>] warn_slowpath_fmt+0x48/0x50
[112065.261922] [<ffffffffa032949e>] ? btrfs_free_path+0x26/0x29 [btrfs]
[112065.262211] [<ffffffffa0325990>] __btrfs_abort_transaction+0x50/0x10b [btrfs]
[112065.262545] [<ffffffffa036b1d6>] btrfs_remove_chunk+0x537/0x58b [btrfs]
[112065.262771] [<ffffffffa033840f>] btrfs_delete_unused_bgs+0x1de/0x21b [btrfs]
[112065.263105] [<ffffffffa0343106>] cleaner_kthread+0x100/0x12f [btrfs]
(...)
[112065.264493] ---[ end trace dd7903a975a31a08 ]---
[112065.264673] BTRFS: error (device sdc) in btrfs_remove_chunk:2625: errno=-28 No space left
[112065.264997] BTRFS info (device sdc): forced readonly
9) The clear kthread sees that the BTRFS_FS_STATE_ERROR bit is set in
fs_info->fs_state and calls btrfs_cleanup_transaction(), which in
turn calls btrfs_destroy_pinned_extent();
10) Then btrfs_destroy_pinned_extent() iterates over all the ranges
marked as dirty in fs_info->freed_extents[], and for each one
it calls discard, if the fs was mounted with "-o discard", and
adds the range to the free space cache of the respective block
group;
11) btrfs_trim_block_group(), invoked from the fitrim ioctl code path,
sees the free space entries and performs a discard;
12) After an umount and mount (or fsck), our eb's location on disk was full
of zeroes, and it should have been untouched, because it was marked as
dirty in the fs_info->pinned_extents tree, and therefore used by the
trees that the last committed superblock points to.
Fix this by not performing a discard and not adding the ranges to the free space
caches - it's useless from this point since the fs is now in readonly mode and
we won't write free space caches to disk anymore (otherwise we would leak space)
nor any new superblock. By not adding the ranges to the free space caches, it
prevents other code paths from allocating that space and write to it as well,
therefore being safer and simpler.
This isn't a new problem, as it's been present since 2011 (git commit
acce952b02).
Cc: stable@vger.kernel.org # any kernel released after 2011-01-06
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Always clear a block group's rbnode after removing it from the rbtree to
ensure that any tasks that might be holding a reference on the block group
don't end up accessing stale rbnode left and right child pointers through
next_block_group().
This is a leftover from the change titled:
"Btrfs: fix invalid block group rbtree access after bg is removed"
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The call to remove_extent_mapping() actually deletes the extent map
from the list it's included in - fs_info->pinned_chunks - and that
list is protected by the chunk mutex. Therefore make that call
while holding the chunk mutex and remove the redundant list delete
call because it's a noop.
This fixes an overlook of the patch titled
"Btrfs: fix race between fs trimming and block group remove/allocation"
following the same obvervation from the patch titled
"Btrfs: fix unprotected deletion from pending_chunks list".
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
This was written when we didn't do a caching control for the fast free space
cache loading. However we started doing that a long time ago, and there is
still a small window of time that we could be caching the block group the fast
way, so if there is a caching_ctl at all on the block group just return it, the
callers all wait properly for what they want. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
On block group remove if the corresponding extent map was on the
transaction->pending_chunks list, we were deleting the extent map
from that list, through remove_extent_mapping(), without any
synchronization with chunk allocation (which iterates that list
and adds new elements to it). Fix this by ensure that this is done
while the chunk mutex is held, since that's the mutex that protects
the list in the chunk allocation code path.
This applies on top (depends on) of my previous patch titled:
"Btrfs: fix race between fs trimming and block group remove/allocation"
But the issue in fact was already present before that change, it only
became easier to hit after Josef's 3.18 patch that added automatic
removal of empty block groups.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
On chunk allocation error (label "error_del_extent"), after adding the
extent map to the tree and to the pending chunks list, we would leave
decrementing the extent map's refcount by 2 instead of 3 (our allocation
+ tree reference + list reference).
Also, on chunk/block group removal, if the block group was on the list
pending_chunks we weren't decrementing the respective list reference.
Detected by 'rmmod btrfs':
[20770.105881] kmem_cache_destroy btrfs_extent_map: Slab cache still has objects
[20770.106127] CPU: 2 PID: 11093 Comm: rmmod Tainted: G W L 3.17.0-rc5-btrfs-next-1+ #1
[20770.106128] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[20770.106130] 0000000000000000 ffff8800ba867eb8 ffffffff813e7a13 ffff8800a2e11040
[20770.106132] ffff8800ba867ed0 ffffffff81105d0c 0000000000000000 ffff8800ba867ee0
[20770.106134] ffffffffa035d65e ffff8800ba867ef0 ffffffffa03b0654 ffff8800ba867f78
[20770.106136] Call Trace:
[20770.106142] [<ffffffff813e7a13>] dump_stack+0x45/0x56
[20770.106145] [<ffffffff81105d0c>] kmem_cache_destroy+0x4b/0x90
[20770.106164] [<ffffffffa035d65e>] extent_map_exit+0x1a/0x1c [btrfs]
[20770.106176] [<ffffffffa03b0654>] exit_btrfs_fs+0x27/0x9d3 [btrfs]
[20770.106179] [<ffffffff8109dc97>] SyS_delete_module+0x153/0x1c4
[20770.106182] [<ffffffff8121261b>] ? trace_hardirqs_on_thunk+0x3a/0x3c
[20770.106184] [<ffffffff813ebf52>] system_call_fastpath+0x16/0x1b
This applies on top (depends on) of my previous patch titled:
"Btrfs: fix race between fs trimming and block group remove/allocation"
But the issue in fact was already present before that change, it only
became easier to hit after Josef's 3.18 patch that added automatic
removal of empty block groups.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
There was a free space entry structure memeory leak if a block
group is remove while a free space entry is being trimmed, which
the following diagram explains:
CPU 1 CPU 2
btrfs_trim_block_group()
trim_no_bitmap()
remove free space entry from
block group cache's rbtree
do_trimming()
btrfs_remove_block_group()
btrfs_remove_free_space_cache()
add back free space entry to
block group's cache rbtree
btrfs_put_block_group()
(...)
btrfs_put_block_group()
kfree(bg->free_space_ctl)
kfree(bg)
The free space entry added after doing the discard of its respective
range ends up never being freed.
Detected after doing an "rmmod btrfs" after running the stress test
recently submitted for fstests:
[ 8234.642212] kmem_cache_destroy btrfs_free_space: Slab cache still has objects
[ 8234.642657] CPU: 1 PID: 32276 Comm: rmmod Tainted: G W L 3.17.0-rc5-btrfs-next-2+ #1
[ 8234.642660] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[ 8234.642664] 0000000000000000 ffff8801af1b3eb8 ffffffff8140c7b6 ffff8801dbedd0c0
[ 8234.642670] ffff8801af1b3ed0 ffffffff811149ce 0000000000000000 ffff8801af1b3ee0
[ 8234.642676] ffffffffa042dbe7 ffff8801af1b3ef0 ffffffffa0487422 ffff8801af1b3f78
[ 8234.642682] Call Trace:
[ 8234.642692] [<ffffffff8140c7b6>] dump_stack+0x4d/0x66
[ 8234.642699] [<ffffffff811149ce>] kmem_cache_destroy+0x4d/0x92
[ 8234.642731] [<ffffffffa042dbe7>] btrfs_destroy_cachep+0x63/0x76 [btrfs]
[ 8234.642757] [<ffffffffa0487422>] exit_btrfs_fs+0x9/0xbe7 [btrfs]
[ 8234.642762] [<ffffffff810a76a5>] SyS_delete_module+0x155/0x1c6
[ 8234.642768] [<ffffffff8122a7eb>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 8234.642773] [<ffffffff814122d2>] system_call_fastpath+0x16/0x1b
This applies on top (depends on) of my previous patch titled:
"Btrfs: fix race between fs trimming and block group remove/allocation"
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If the transaction handle doesn't have used blocks but has created new block
groups make sure we turn the fs into readonly mode too. This is because the
new block groups didn't get all their metadata persisted into the chunk and
device trees, and therefore if a subsequent transaction starts, allocates
space from the new block groups, writes data or metadata into that space,
commits successfully and then after we unmount and mount the filesystem
again, the same space can be allocated again for a new block group,
resulting in file data or metadata corruption.
Example where we don't abort the transaction when we fail to finish the
chunk allocation (add items to the chunk and device trees) and later a
future transaction where the block group is removed fails because it can't
find the chunk item in the chunk tree:
[25230.404300] WARNING: CPU: 0 PID: 7721 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x50/0xfc [btrfs]()
[25230.404301] BTRFS: Transaction aborted (error -28)
[25230.404302] Modules linked in: btrfs dm_flakey nls_utf8 fuse xor raid6_pq ntfs vfat msdos fat xfs crc32c_generic libcrc32c ext3 jbd ext2 dm_mod nfsd auth_rpcgss oid_registry nfs_acl nfs lockd fscache sunrpc loop psmouse i2c_piix4 i2ccore parport_pc parport processor button pcspkr serio_raw thermal_sys evdev microcode ext4 crc16 jbd2 mbcache sr_mod cdrom ata_generic sg sd_mod crc_t10dif crct10dif_generic crct10dif_common virtio_scsi floppy e1000 ata_piix libata virtio_pci virtio_ring scsi_mod virtio [last unloaded: btrfs]
[25230.404325] CPU: 0 PID: 7721 Comm: xfs_io Not tainted 3.17.0-rc5-btrfs-next-1+ #1
[25230.404326] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[25230.404328] 0000000000000000 ffff88004581bb08 ffffffff813e7a13 ffff88004581bb50
[25230.404330] ffff88004581bb40 ffffffff810423aa ffffffffa049386a 00000000ffffffe4
[25230.404332] ffffffffa05214c0 000000000000240c ffff88010fc8f800 ffff88004581bba8
[25230.404334] Call Trace:
[25230.404338] [<ffffffff813e7a13>] dump_stack+0x45/0x56
[25230.404342] [<ffffffff810423aa>] warn_slowpath_common+0x7f/0x98
[25230.404351] [<ffffffffa049386a>] ? __btrfs_abort_transaction+0x50/0xfc [btrfs]
[25230.404353] [<ffffffff8104240b>] warn_slowpath_fmt+0x48/0x50
[25230.404362] [<ffffffffa049386a>] __btrfs_abort_transaction+0x50/0xfc [btrfs]
[25230.404374] [<ffffffffa04a8c43>] btrfs_create_pending_block_groups+0x10c/0x135 [btrfs]
[25230.404387] [<ffffffffa04b77fd>] __btrfs_end_transaction+0x7e/0x2de [btrfs]
[25230.404398] [<ffffffffa04b7a6d>] btrfs_end_transaction+0x10/0x12 [btrfs]
[25230.404408] [<ffffffffa04a3d64>] btrfs_check_data_free_space+0x111/0x1f0 [btrfs]
[25230.404421] [<ffffffffa04c53bd>] __btrfs_buffered_write+0x160/0x48d [btrfs]
[25230.404425] [<ffffffff811a9268>] ? cap_inode_need_killpriv+0x2d/0x37
[25230.404429] [<ffffffff810f6501>] ? get_page+0x1a/0x2b
[25230.404441] [<ffffffffa04c7c95>] btrfs_file_write_iter+0x321/0x42f [btrfs]
[25230.404443] [<ffffffff8110f5d9>] ? handle_mm_fault+0x7f3/0x846
[25230.404446] [<ffffffff813e98c5>] ? mutex_unlock+0x16/0x18
[25230.404449] [<ffffffff81138d68>] new_sync_write+0x7c/0xa0
[25230.404450] [<ffffffff81139401>] vfs_write+0xb0/0x112
[25230.404452] [<ffffffff81139c9d>] SyS_pwrite64+0x66/0x84
[25230.404454] [<ffffffff813ebf52>] system_call_fastpath+0x16/0x1b
[25230.404455] ---[ end trace 5aa5684fdf47ab38 ]---
[25230.404458] BTRFS warning (device sdc): btrfs_create_pending_block_groups:9228: Aborting unused transaction(No space left).
[25288.084814] BTRFS: error (device sdc) in btrfs_free_chunk:2509: errno=-2 No such entry (Failed lookup while freeing chunk.)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Trimming is completely transactionless, and the way it operates consists
of hiding free space entries from a block group, perform the trim/discard
and then make the free space entries visible again.
Therefore while a free space entry is being trimmed, we can have free space
cache writing running in parallel (as part of a transaction commit) which
will miss the free space entry. This means that an unmount (or crash/reboot)
after that transaction commit and mount again before another transaction
starts/commits after the discard finishes, we will have some free space
that won't be used again unless the free space cache is rebuilt. After the
unmount, fsck (btrfsck, btrfs check) reports the issue like the following
example:
*** fsck.btrfs output ***
checking extents
checking free space cache
There is no free space entry for 521764864-521781248
There is no free space entry for 521764864-1103101952
cache appears valid but isnt 29360128
Checking filesystem on /dev/sdc
UUID: b4789e27-4774-4626-98e9-ae8dfbfb0fb5
found 1235681286 bytes used err is -22
(...)
Another issue caused by this race is a crash while writing bitmap entries
to the cache, because while the cache writeout task accesses the bitmaps,
the trim task can be concurrently modifying the bitmap or worse might
be freeing the bitmap. The later case results in the following crash:
[55650.804460] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
[55650.804835] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd fscache sunrpc loop parport_pc parport i2c_piix4 psmouse evdev pcspkr microcode processor i2ccore serio_raw thermal_sys button ext4 crc16 jbd2 mbcache sg sd_mod crc_t10dif sr_mod cdrom crct10dif_generic crct10dif_common ata_generic virtio_scsi floppy ata_piix libata virtio_pci virtio_ring virtio scsi_mod e1000 [last unloaded: btrfs]
[55650.806169] CPU: 1 PID: 31002 Comm: btrfs-transacti Tainted: G W 3.17.0-rc5-btrfs-next-1+ #1
[55650.806493] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[55650.806867] task: ffff8800b12f6410 ti: ffff880071538000 task.ti: ffff880071538000
[55650.807166] RIP: 0010:[<ffffffffa037cf45>] [<ffffffffa037cf45>] write_bitmap_entries+0x65/0xbb [btrfs]
[55650.807514] RSP: 0018:ffff88007153bc30 EFLAGS: 00010246
[55650.807687] RAX: 000000005d1ec000 RBX: ffff8800a665df08 RCX: 0000000000000400
[55650.807885] RDX: ffff88005d1ec000 RSI: 6b6b6b6b6b6b6b6b RDI: ffff88005d1ec000
[55650.808017] RBP: ffff88007153bc58 R08: 00000000ddd51536 R09: 00000000000001e0
[55650.808017] R10: 0000000000000000 R11: 0000000000000037 R12: 6b6b6b6b6b6b6b6b
[55650.808017] R13: ffff88007153bca8 R14: 6b6b6b6b6b6b6b6b R15: ffff88007153bc98
[55650.808017] FS: 0000000000000000(0000) GS:ffff88023ec80000(0000) knlGS:0000000000000000
[55650.808017] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[55650.808017] CR2: 0000000002273b88 CR3: 00000000b18f6000 CR4: 00000000000006e0
[55650.808017] Stack:
[55650.808017] ffff88020e834e00 ffff880172d68db0 0000000000000000 ffff88019257c800
[55650.808017] ffff8801d42ea720 ffff88007153bd10 ffffffffa037d2fa ffff880224e99180
[55650.808017] ffff8801469a6188 ffff880224e99140 ffff880172d68c50 00000003000000b7
[55650.808017] Call Trace:
[55650.808017] [<ffffffffa037d2fa>] __btrfs_write_out_cache+0x1ea/0x37f [btrfs]
[55650.808017] [<ffffffffa037d959>] btrfs_write_out_cache+0xa1/0xd8 [btrfs]
[55650.808017] [<ffffffffa033936b>] btrfs_write_dirty_block_groups+0x4b5/0x505 [btrfs]
[55650.808017] [<ffffffffa03aa98e>] commit_cowonly_roots+0x15e/0x1f7 [btrfs]
[55650.808017] [<ffffffff813eb9c7>] ? _raw_spin_lock+0xe/0x10
[55650.808017] [<ffffffffa0346e46>] btrfs_commit_transaction+0x411/0x882 [btrfs]
[55650.808017] [<ffffffffa03432a4>] transaction_kthread+0xf2/0x1a4 [btrfs]
[55650.808017] [<ffffffffa03431b2>] ? btrfs_cleanup_transaction+0x3d8/0x3d8 [btrfs]
[55650.808017] [<ffffffff8105966b>] kthread+0xb7/0xbf
[55650.808017] [<ffffffff810595b4>] ? __kthread_parkme+0x67/0x67
[55650.808017] [<ffffffff813ebeac>] ret_from_fork+0x7c/0xb0
[55650.808017] [<ffffffff810595b4>] ? __kthread_parkme+0x67/0x67
[55650.808017] Code: 4c 89 ef 8d 70 ff e8 d4 fc ff ff 41 8b 45 34 41 39 45 30 7d 5c 31 f6 4c 89 ef e8 80 f6 ff ff 49 8b 7d 00 4c 89 f6 b9 00 04 00 00 <f3> a5 4c 89 ef 41 8b 45 30 8d 70 ff e8 a3 fc ff ff 41 8b 45 34
[55650.808017] RIP [<ffffffffa037cf45>] write_bitmap_entries+0x65/0xbb [btrfs]
[55650.808017] RSP <ffff88007153bc30>
[55650.815725] ---[ end trace 1c032e96b149ff86 ]---
Fix this by serializing both tasks in such a way that cache writeout
doesn't wait for the trim/discard of free space entries to finish and
doesn't miss any free space entry.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Our fs trim operation, which is completely transactionless (doesn't start
or joins an existing transaction) consists of visiting all block groups
and then for each one to iterate its free space entries and perform a
discard operation against the space range represented by the free space
entries. However before performing a discard, the corresponding free space
entry is removed from the free space rbtree, and when the discard completes
it is added back to the free space rbtree.
If a block group remove operation happens while the discard is ongoing (or
before it starts and after a free space entry is hidden), we end up not
waiting for the discard to complete, remove the extent map that maps
logical address to physical addresses and the corresponding chunk metadata
from the the chunk and device trees. After that and before the discard
completes, the current running transaction can finish and a new one start,
allowing for new block groups that map to the same physical addresses to
be allocated and written to.
So fix this by keeping the extent map in memory until the discard completes
so that the same physical addresses aren't reused before it completes.
If the physical locations that are under a discard operation end up being
used for a new metadata block group for example, and dirty metadata extents
are written before the discard finishes (the VM might call writepages() of
our btree inode's i_mapping for example, or an fsync log commit happens) we
end up overwriting metadata with zeroes, which leads to errors from fsck
like the following:
checking extents
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
read block failed check_tree_block
owner ref check failed [833912832 16384]
Errors found in extent allocation tree or chunk allocation
checking free space cache
checking fs roots
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
Check tree block failed, want=833912832, have=0
read block failed check_tree_block
root 5 root dir 256 error
root 5 inode 260 errors 2001, no inode item, link count wrong
unresolved ref dir 256 index 0 namelen 8 name foobar_3 filetype 1 errors 6, no dir index, no inode ref
root 5 inode 262 errors 2001, no inode item, link count wrong
unresolved ref dir 256 index 0 namelen 8 name foobar_5 filetype 1 errors 6, no dir index, no inode ref
root 5 inode 263 errors 2001, no inode item, link count wrong
(...)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
There's a race between adding a block group to the list of the unused
block groups and removing an unused block group (cleaner kthread) that
leads to freeing extents that are in use or a crash during transaction
commmit. Basically the cleaner kthread, when executing
btrfs_delete_unused_bgs(), might catch the newly added block group to
the list fs_info->unused_bgs and clear the range representing the whole
group from fs_info->freed_extents[] before the task that added the block
group to the list (running update_block_group()) marked the last freed
extent as dirty in fs_info->freed_extents (pinned_extents).
That is:
CPU 1 CPU 2
btrfs_delete_unused_bgs()
update_block_group()
add block group to
fs_info->unused_bgs
got block group from the list
clear_extent_bits for the whole
block group range in freed_extents[]
set_extent_dirty for the
range covering the freed
extent in freed_extents[]
(fs_info->pinned_extents)
block group deleted, and a new block
group with the same logical address is
created
reserve space from the new block group
for new data or metadata - the reserved
space overlaps the range specified by
CPU 1 for set_extent_dirty()
commit transaction
find all ranges marked as dirty in
fs_info->pinned_extents, clear them
and add them to the free space cache
Alternatively, if CPU 2 doesn't create a new block group with the same
logical address, we get a crash/BUG_ON at transaction commit when unpining
extent ranges because we can't find a block group for the range marked as
dirty by CPU 1. Sample trace:
[ 2163.426462] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
[ 2163.426640] Modules linked in: btrfs xor raid6_pq dm_thin_pool dm_persistent_data dm_bio_prison dm_bufio crc32c_generic libcrc32c dm_mod nfsd auth_rpc
gss oid_registry nfs_acl nfs lockd fscache sunrpc loop psmouse parport_pc parport i2c_piix4 processor thermal_sys i2ccore evdev button pcspkr microcode serio_raw ext4 crc16 jbd2 mbcache
sg sr_mod cdrom sd_mod crc_t10dif crct10dif_generic crct10dif_common ata_generic virtio_scsi floppy ata_piix libata e1000 scsi_mod virtio_pci virtio_ring virtio
[ 2163.428209] CPU: 0 PID: 11858 Comm: btrfs-transacti Tainted: G W 3.17.0-rc5-btrfs-next-1+ #1
[ 2163.428519] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[ 2163.428875] task: ffff88009f2c0650 ti: ffff8801356bc000 task.ti: ffff8801356bc000
[ 2163.429157] RIP: 0010:[<ffffffffa037728e>] [<ffffffffa037728e>] unpin_extent_range.isra.58+0x62/0x192 [btrfs]
[ 2163.429562] RSP: 0018:ffff8801356bfda8 EFLAGS: 00010246
[ 2163.429802] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 2163.429990] RDX: 0000000041bfffff RSI: 0000000001c00000 RDI: ffff880024307080
[ 2163.430042] RBP: ffff8801356bfde8 R08: 0000000000000068 R09: ffff88003734f118
[ 2163.430042] R10: ffff8801356bfcb8 R11: fffffffffffffb69 R12: ffff8800243070d0
[ 2163.430042] R13: 0000000083c04000 R14: ffff8800751b0f00 R15: ffff880024307000
[ 2163.430042] FS: 0000000000000000(0000) GS:ffff88013f400000(0000) knlGS:0000000000000000
[ 2163.430042] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 2163.430042] CR2: 00007ff10eb43fc0 CR3: 0000000004cb8000 CR4: 00000000000006f0
[ 2163.430042] Stack:
[ 2163.430042] ffff8800243070d0 0000000083c08000 0000000083c07fff ffff88012d6bc800
[ 2163.430042] ffff8800243070d0 ffff8800751b0f18 ffff8800751b0f00 0000000000000000
[ 2163.430042] ffff8801356bfe18 ffffffffa037a481 0000000083c04000 0000000083c07fff
[ 2163.430042] Call Trace:
[ 2163.430042] [<ffffffffa037a481>] btrfs_finish_extent_commit+0xac/0xbf [btrfs]
[ 2163.430042] [<ffffffffa038c06d>] btrfs_commit_transaction+0x6ee/0x882 [btrfs]
[ 2163.430042] [<ffffffffa03881f1>] transaction_kthread+0xf2/0x1a4 [btrfs]
[ 2163.430042] [<ffffffffa03880ff>] ? btrfs_cleanup_transaction+0x3d8/0x3d8 [btrfs]
[ 2163.430042] [<ffffffff8105966b>] kthread+0xb7/0xbf
[ 2163.430042] [<ffffffff810595b4>] ? __kthread_parkme+0x67/0x67
[ 2163.430042] [<ffffffff813ebeac>] ret_from_fork+0x7c/0xb0
[ 2163.430042] [<ffffffff810595b4>] ? __kthread_parkme+0x67/0x67
So fix this by making update_block_group() first set the range as dirty
in pinned_extents before adding the block group to the unused_bgs list.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we grab a block group, for example in btrfs_trim_fs(), we will be holding
a reference on it but the block group can be removed after we got it (via
btrfs_remove_block_group), which means it will no longer be part of the
rbtree.
However, btrfs_remove_block_group() was only calling rb_erase() which leaves
the block group's rb_node left and right child pointers with the same content
they had before calling rb_erase. This was dangerous because a call to
next_block_group() would access the node's left and right child pointers (via
rb_next), which can be no longer valid.
Fix this by clearing a block group's node after removing it from the tree,
and have next_block_group() do a tree search to get the next block group
instead of using rb_next() if our block group was removed.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The commit c404e0dc (Btrfs: fix use-after-free in the finishing
procedure of the device replace) fixed a use-after-free problem
which happened when removing the source device at the end of device
replace, but at that time, btrfs didn't support device replace
on raid56, so we didn't fix the problem on the raid56 profile.
Currently, we implemented device replace for raid56, so we need
kick that problem out before we enable that function for raid56.
The fix method is very simple, we just increase the bio per-cpu
counter before we submit a raid56 io, and decrease the counter
when the raid56 io ends.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
This function reused the code of parity scrub, and we just write
the right parity or corrected parity into the target device before
the parity scrub end.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
The implementation is simple:
- In order to avoid changing the code logic of btrfs_map_bio and
RAID56, we add the stripes of the replace target devices at the
end of the stripe array in btrfs bio, and we sort those target
device stripes in the array. And we keep the number of the target
device stripes in the btrfs bio.
- Except write operation on RAID56, all the other operation don't
take the target device stripes into account.
- When we do write operation, we read the data from the common devices
and calculate the parity. Then write the dirty data and new parity
out, at this time, we will find the relative replace target stripes
and wirte the relative data into it.
Note: The function that copying old data on the source device to
the target device was implemented in the past, it is similar to
the other RAID type.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
The implementation is:
- Read and check all the data with checksum in the same stripe.
All the data which has checksum is COW data, and we are sure
that it is not changed though we don't lock the stripe. because
the space of that data just can be reclaimed after the current
transction is committed, and then the fs can use it to store the
other data, but when doing scrub, we hold the current transaction,
that is that data can not be recovered, it is safe that read and check
it out of the stripe lock.
- Lock the stripe
- Read out all the data without checksum and parity
The data without checksum and the parity may be changed if we don't
lock the stripe, so we need read it in the stripe lock context.
- Check the parity
- Re-calculate the new parity and write back it if the old parity
is not right
- Unlock the stripe
If we can not read out the data or the data we read is corrupted,
we will try to repair it. If the repair fails. we will mark the
horizontal sub-stripe(pages on the same horizontal) as corrupted
sub-stripe, and we will skip the parity check and repair of that
horizontal sub-stripe.
And in order to skip the horizontal sub-stripe that has no data, we
introduce a bitmap. If there is some data on the horizontal sub-stripe,
we will the relative bit to 1, and when we check and repair the
parity, we will skip those horizontal sub-stripes that the relative
bits is 0.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
We will introduce new operation type later, if we still use integer
variant as bool variant to record the operation type, we would add new
variant and increase the size of raid bio structure. It is not good,
by this patch, we define different number for different operation,
and we can just use a variant to record the operation type.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
This patch implement the RAID5/6 common data repair function, the
implementation is similar to the scrub on the other RAID such as
RAID1, the differentia is that we don't read the data from the
mirror, we use the data repair function of RAID5/6.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Because we will reuse bbio and raid_map during the scrub later, it is
better that we don't change any variant of bbio and don't free it at
the end of IO request. So we introduced similar variants into the raid
bio, and don't access those bbio's variants any more.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
stripe_index's value was set again in latter line:
stripe_index = 0;
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
bbio_ret in this condition is always !NULL because previous code
already have a check-and-skip:
4908 if (!bbio_ret)
4909 goto out;
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Don Bailey noticed that our page zeroing for compression at end-io time
isn't complete. This reworks a patch from Linus to push the zeroing
into the zlib and lzo specific functions instead of trying to handle the
corners inside btrfs_decompress_buf2page
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reported-by: Don A. Bailey <donb@securitymouse.com>
cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If right after starting the snapshot creation ioctl we perform a write against a
file followed by a truncate, with both operations increasing the file's size, we
can get a snapshot tree that reflects a state of the source subvolume's tree where
the file truncation happened but the write operation didn't. This leaves a gap
between 2 file extent items of the inode, which makes btrfs' fsck complain about it.
For example, if we perform the following file operations:
$ mkfs.btrfs -f /dev/vdd
$ mount /dev/vdd /mnt
$ xfs_io -f \
-c "pwrite -S 0xaa -b 32K 0 32K" \
-c "fsync" \
-c "pwrite -S 0xbb -b 32770 16K 32770" \
-c "truncate 90123" \
/mnt/foobar
and the snapshot creation ioctl was just called before the second write, we often
can get the following inode items in the snapshot's btree:
item 120 key (257 INODE_ITEM 0) itemoff 7987 itemsize 160
inode generation 146 transid 7 size 90123 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 flags 0x0
item 121 key (257 INODE_REF 256) itemoff 7967 itemsize 20
inode ref index 282 namelen 10 name: foobar
item 122 key (257 EXTENT_DATA 0) itemoff 7914 itemsize 53
extent data disk byte 1104855040 nr 32768
extent data offset 0 nr 32768 ram 32768
extent compression 0
item 123 key (257 EXTENT_DATA 53248) itemoff 7861 itemsize 53
extent data disk byte 0 nr 0
extent data offset 0 nr 40960 ram 40960
extent compression 0
There's a file range, corresponding to the interval [32K; ALIGN(16K + 32770, 4096)[
for which there's no file extent item covering it. This is because the file write
and file truncate operations happened both right after the snapshot creation ioctl
called btrfs_start_delalloc_inodes(), which means we didn't start and wait for the
ordered extent that matches the write and, in btrfs_setsize(), we were able to call
btrfs_cont_expand() before being able to commit the current transaction in the
snapshot creation ioctl. So this made it possibe to insert the hole file extent
item in the source subvolume (which represents the region added by the truncate)
right before the transaction commit from the snapshot creation ioctl.
Btrfs' fsck tool complains about such cases with a message like the following:
"root 331 inode 257 errors 100, file extent discount"
>From a user perspective, the expectation when a snapshot is created while those
file operations are being performed is that the snapshot will have a file that
either:
1) is empty
2) only the first write was captured
3) only the 2 writes were captured
4) both writes and the truncation were captured
But never capture a state where only the first write and the truncation were
captured (since the second write was performed before the truncation).
A test case for xfstests follows.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Move the logic from the snapshot creation ioctl into send. This avoids
doing the transaction commit if send isn't used, and ensures that if
a crash/reboot happens after the transaction commit that created the
snapshot and before the transaction commit that switched the commit
root, send will not get a commit root that differs from the main root
(that has orphan items).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Due to ignoring errors returned by clear_extent_bits (at the moment only
-ENOMEM is possible), we can end up freeing an extent that is actually in
use (i.e. return the extent to the free space cache).
The sequence of steps that lead to this:
1) Cleaner thread starts execution and calls btrfs_delete_unused_bgs(), with
the goal of freeing empty block groups;
2) btrfs_delete_unused_bgs() finds an empty block group, joins the current
transaction (or starts a new one if none is running) and attempts to
clear the EXTENT_DIRTY bit for the block group's range from freed_extents[0]
and freed_extents[1] (of which one corresponds to fs_info->pinned_extents);
3) Clearing the EXTENT_DIRTY bit (via clear_extent_bits()) fails with
-ENOMEM, but such error is ignored and btrfs_delete_unused_bgs() proceeds
to delete the block group and the respective chunk, while pinned_extents
remains with that bit set for the whole (or a part of the) range covered
by the block group;
4) Later while the transaction is still running, the chunk ends up being reused
for a new block group (maybe for different purpose, data or metadata), and
extents belonging to the new block group are allocated for file data or btree
nodes/leafs;
5) The current transaction is committed, meaning that we unpinned one or more
extents from the new block group (through btrfs_finish_extent_commit() and
unpin_extent_range()) which are now being used for new file data or new
metadata (through btrfs_finish_extent_commit() and unpin_extent_range()).
And unpinning means we returned the extents to the free space cache of the
new block group, which implies those extents can be used for future allocations
while they're still in use.
Alternatively, we can hit a BUG_ON() when doing a lookup for a block group's cache
object in unpin_extent_range() if a new block group didn't end up being allocated for
the same chunk (step 4 above).
Fix this by not freeing the block group and chunk if we fail to clear the dirty bit.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Fengguang's build monster reported warnings on some arches because we
don't have vmalloc.h included
Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: fengguang.wu@intel.com
The following lockdep warning is triggered during xfstests:
[ 1702.980872] =========================================================
[ 1702.981181] [ INFO: possible irq lock inversion dependency detected ]
[ 1702.981482] 3.18.0-rc1 #27 Not tainted
[ 1702.981781] ---------------------------------------------------------
[ 1702.982095] kswapd0/77 just changed the state of lock:
[ 1702.982415] (&delayed_node->mutex){+.+.-.}, at: [<ffffffffa03b0b51>] __btrfs_release_delayed_node+0x41/0x1f0 [btrfs]
[ 1702.982794] but this lock took another, RECLAIM_FS-unsafe lock in the past:
[ 1702.983160] (&fs_info->dev_replace.lock){+.+.+.}
and interrupts could create inverse lock ordering between them.
[ 1702.984675]
other info that might help us debug this:
[ 1702.985524] Chain exists of:
&delayed_node->mutex --> &found->groups_sem --> &fs_info->dev_replace.lock
[ 1702.986799] Possible interrupt unsafe locking scenario:
[ 1702.987681] CPU0 CPU1
[ 1702.988137] ---- ----
[ 1702.988598] lock(&fs_info->dev_replace.lock);
[ 1702.989069] local_irq_disable();
[ 1702.989534] lock(&delayed_node->mutex);
[ 1702.990038] lock(&found->groups_sem);
[ 1702.990494] <Interrupt>
[ 1702.990938] lock(&delayed_node->mutex);
[ 1702.991407]
*** DEADLOCK ***
It is because the btrfs_kobj_{add/rm}_device() will call memory
allocation with GFP_KERNEL,
which may flush fs page cache to free space, waiting for it self to do
the commit, causing the deadlock.
To solve the problem, move btrfs_kobj_{add/rm}_device() out of the
dev_replace lock range, also involing split the
btrfs_rm_dev_replace_srcdev() function into remove and free parts.
Now only btrfs_rm_dev_replace_remove_srcdev() is called in dev_replace
lock range, and kobj_{add/rm} and btrfs_rm_dev_replace_free_srcdev() are
called out of the lock range.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs deadlock fix from Chris Mason:
"This has a fix for a long standing deadlock that we've been trying to
nail down for a while. It ended up being a bad interaction with the
fair reader/writer locks and the order btrfs reacquires locks in the
btree"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix lockups from btrfs_clear_path_blocking
When doing a fsync with a fast path we have a time window where we can miss
the fact that writeback of some file data failed, and therefore we endup
returning success (0) from fsync when we should return an error.
The steps that lead to this are the following:
1) We start all ordered extents by calling filemap_fdatawrite_range();
2) We do some other work like locking the inode's i_mutex, start a transaction,
start a log transaction, etc;
3) We enter btrfs_log_inode(), acquire the inode's log_mutex and collect all the
ordered extents from inode's ordered tree into a list;
4) But by the time we do ordered extent collection, some ordered extents we started
at step 1) might have already completed with an error, and therefore we didn't
found them in the ordered tree and had no idea they finished with an error. This
makes our fsync return success (0) to userspace, but has no bad effects on the log
like for example insertion of file extent items into the log that point to unwritten
extents, because the invalid extent maps were removed before the ordered extent
completed (in inode.c:btrfs_finish_ordered_io).
So after collecting the ordered extents just check if the inode's i_mapping has any
error flags set (AS_EIO or AS_ENOSPC) and leave with an error if it does. Whenever
writeback fails for a page of an ordered extent, we call mapping_set_error (done in
extent_io.c:end_extent_writepage, called by extent_io.c:end_bio_extent_writepage)
that sets one of those error flags in the inode's i_mapping flags.
This change also has the side effect of fixing the issue where for fast fsyncs we
never checked/cleared the error flags from the inode's i_mapping flags, which means
that a full fsync performed after a fast fsync could get such errors that belonged
to the fast fsync - because the full fsync calls btrfs_wait_ordered_range() which
calls filemap_fdatawait_range(), and the later checks for and clears those flags,
while for fast fsyncs we never call filemap_fdatawait_range() or anything else
that checks for and clears the error flags from the inode's i_mapping.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Instead of collecting all ordered extents from the inode's ordered tree
and then wait for all of them to complete, just collect the ones that
overlap the fsync range.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If an error happens during writeback of log btree extents, make sure the
error is returned to the caller (fsync), so that it takes proper action
(commit current transaction) instead of writing a superblock that points
to log btrees with all or some nodes that weren't durably persisted.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We use the modified list to keep track of which extents have been modified so we
know which ones are candidates for logging at fsync() time. Newly modified
extents are added to the list at modification time, around the same time the
ordered extent is created. We do this so that we don't have to wait for ordered
extents to complete before we know what we need to log. The problem is when
something like this happens
log extent 0-4k on inode 1
copy csum for 0-4k from ordered extent into log
sync log
commit transaction
log some other extent on inode 1
ordered extent for 0-4k completes and adds itself onto modified list again
log changed extents
see ordered extent for 0-4k has already been logged
at this point we assume the csum has been copied
sync log
crash
On replay we will see the extent 0-4k in the log, drop the original 0-4k extent
which is the same one that we are replaying which also drops the csum, and then
we won't find the csum in the log for that bytenr. This of course causes us to
have errors about not having csums for certain ranges of our inode. So remove
the modified list manipulation in unpin_extent_cache, any modified extents
should have been added well before now, and we don't want them re-logged. This
fixes my test that I could reliably reproduce this problem with. Thanks,
cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Liu Bo pointed out that my previous fix would lose the generation update in the
scenario I described. It is actually much worse than that, we could lose the
entire extent if we lose power right after the transaction commits. Consider
the following
write extent 0-4k
log extent in log tree
commit transaction
< power fail happens here
ordered extent completes
We would lose the 0-4k extent because it hasn't updated the actual fs tree, and
the transaction commit will reset the log so it isn't replayed. If we lose
power before the transaction commit we are save, otherwise we are not.
Fix this by keeping track of all extents we logged in this transaction. Then
when we go to commit the transaction make sure we wait for all of those ordered
extents to complete before proceeding. This will make sure that if we lose
power after the transaction commit we still have our data. This also fixes the
problem of the improperly updated extent generation. Thanks,
cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we have two fsync()'s race on different subvols one will do all of its work
to get into the log_tree, wait on it's outstanding IO, and then allow the
log_tree to finish it's commit. The problem is we were just free'ing that
subvols logged extents instead of waiting on them, so whoever lost the race
wouldn't really have their data on disk. Fix this by waiting properly instead
of freeing the logged extents. Thanks,
cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The sizes that are obtained from space infos are in raw units and have
to be adjusted according to the raid factor. This was missing for
f_bavail and df reported doubled size for raid1.
Reported-by: Martin Steigerwald <Martin@lichtvoll.de>
Fixes: ba7b6e62f4 ("btrfs: adjust statfs calculations according to raid profiles")
CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
This can be reproduced by fstests: btrfs/070
The scenario is like the following:
replace worker thread defrag thread
--------------------- -------------
copy_nocow_pages_worker btrfs_defrag_file
copy_nocow_pages_for_inode ...
btrfs_writepages
|A| lock_extent_bits extent_write_cache_pages
|B| lock_page
__extent_writepage
... writepage_delalloc
find_lock_delalloc_range
|B| lock_extent_bits
find_or_create_page
pagecache_get_page
|A| lock_page
This leads to an ABBA pattern deadlock. To fix it,
o we just change it to an AABB pattern which means to @unlock_extent_bits()
before we @lock_page(), and in this way the @extent_read_full_page_nolock()
is no longer in an locked context, so change it back to @extent_read_full_page()
to regain protection.
o Since we @unlock_extent_bits() earlier, then before @write_page_nocow(),
the extent may not really point at the physical block we want, so we
have to check it before write.
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Replacing a xattr consists of doing a lookup for its existing value, delete
the current value from the respective leaf, release the search path and then
finally insert the new value. This leaves a time window where readers (getxattr,
listxattrs) won't see any value for the xattr. Xattrs are used to store ACLs,
so this has security implications.
This change also fixes 2 other existing issues which were:
*) Deleting the old xattr value without verifying first if the new xattr will
fit in the existing leaf item (in case multiple xattrs are packed in the
same item due to name hash collision);
*) Returning -EEXIST when the flag XATTR_CREATE is given and the xattr doesn't
exist but we have have an existing item that packs muliple xattrs with
the same name hash as the input xattr. In this case we should return ENOSPC.
A test case for xfstests follows soon.
Thanks to Alexandre Oliva for reporting the non-atomicity of the xattr replace
implementation.
Reported-by: Alexandre Oliva <oliva@gnu.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We try to allocate an extent state structure before acquiring the extent
state tree's spinlock as we might need a new one later and therefore avoid
doing later an atomic allocation while holding the tree's spinlock. However
we returned -ENOMEM if that initial non-atomic allocation failed, which is
a bit excessive since we might end up not needing the pre-allocated extent
state at all - for the case where the tree doesn't have any extent states
that cover the input range and cover too any other range. Therefore don't
return -ENOMEM if that pre-allocation fails.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Our gluster boxes get several thousand statfs() calls per second, which begins
to suck hardcore with all of the lock contention on the chunk mutex and dev list
mutex. We don't really need to hold these things, if we have transient
weirdness with statfs() because of the chunk allocator we don't care, so remove
this locking.
We still need the dev_list lock if you mount with -o alloc_start however, which
is a good argument for nuking that thing from orbit, but that's a patch for
another day. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Our gluster boxes were spending lots of time in statfs because our fs'es are
huge. The problem is statfs loops through all of the block groups looking for
read only block groups, and when you have several terabytes worth of data that
ends up being a lot of block groups. Move the read only block groups onto a
read only list and only proces that list in
btrfs_account_ro_block_groups_free_space to reduce the amount of churn. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Copy&paste errors in some messages and add few more missing macro
accessors.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The xfstest btrfs/014 which tests the balance operation caused that the
check_int module complained that known blocks changed their physical
location. Since this is not an error in this case, only print such
message if the verbose mode was enabled.
Reported-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Tested-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
The xfstest btrfs/014 which tests the balance operation caused issues with
the check_int module. The attempt was made to use btrfs_map_block() to
find the physical location for a written block. However, this was not
at all needed since the location of the written block was known since
a hook to submit_bio() was the reason for entering the check_int module.
Additionally, after a block relocation it happened that btrfs_map_block()
failed causing misleading error messages afterwards.
This patch changes the check_int module to use the known information of
the physical location from the bio.
Reported-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Tested-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
We try to allocate an extent state before acquiring the tree's spinlock
just in case we end up needing to split an existing extent state into two.
If that allocation failed, we would return -ENOMEM.
However, our only single caller (transaction/log commit code), passes in
an extent state that was cached from a call to find_first_extent_bit() and
that has a very high chance to match exactly the input range (always true
for a transaction commit and very often, but not always, true for a log
commit) - in this case we end up not needing at all that initial extent
state used for an eventual split. Therefore just don't return -ENOMEM if
we can't allocate the temporary extent state, since we might not need it
at all, and if we end up needing one, we'll do it later anyway.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Right now the only caller of find_first_extent_bit() that is interested
in caching extent states (transaction or log commit), never gets an extent
state cached. This is because find_first_extent_bit() only caches states
that have at least one of the flags EXTENT_IOBITS or EXTENT_BOUNDARY, and
the transaction/log commit caller always passes a tree that doesn't have
ever extent states with any of those flags (they can only have one of the
following flags: EXTENT_DIRTY, EXTENT_NEW or EXTENT_NEED_WAIT).
This change together with the following one in the patch series (titled
"Btrfs: avoid returning -ENOMEM in convert_extent_bit() too early") will
help reduce significantly the chances of calls to convert_extent_bit()
fail with -ENOMEM when called from the transaction/log commit code.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When committing a transaction or a log, we look for btree extents that
need to be durably persisted by searching for ranges in a io tree that
have some bits set (EXTENT_DIRTY or EXTENT_NEW). We then attempt to clear
those bits and set the EXTENT_NEED_WAIT bit, with calls to the function
convert_extent_bit, and then start writeback for the extents.
That function however can return an error (at the moment only -ENOMEM
is possible, specially when it does GFP_ATOMIC allocation requests
through alloc_extent_state_atomic) - that means the ranges didn't got
the EXTENT_NEED_WAIT bit set (or at least not for the whole range),
which in turn means a call to btrfs_wait_marked_extents() won't find
those ranges for which we started writeback, causing a transaction
commit or a log commit to persist a new superblock without waiting
for the writeback of extents in that range to finish first.
Therefore if a crash happens after persisting the new superblock and
before writeback finishes, we have a superblock pointing to roots that
weren't fully persisted or roots that point to nodes or leafs that weren't
fully persisted, causing all sorts of unexpected/bad behaviour as we endup
reading garbage from disk or the content of some node/leaf from a past
generation that got cowed or deleted and is no longer valid (for this later
case we end up getting error messages like "parent transid verify failed on
X wanted Y found Z" when reading btree nodes/leafs from disk).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
device replace could fail due to another running scrub process or any
other errors btrfs_scrub_dev() may hit, but this failure doesn't get
returned to userspace.
The following steps could reproduce this issue
mkfs -t btrfs -f /dev/sdb1 /dev/sdb2
mount /dev/sdb1 /mnt/btrfs
while true; do btrfs scrub start -B /mnt/btrfs >/dev/null 2>&1; done &
btrfs replace start -Bf /dev/sdb2 /dev/sdb3 /mnt/btrfs
# if this replace succeeded, do the following and repeat until
# you see this log in dmesg
# BTRFS: btrfs_scrub_dev(/dev/sdb2, 2, /dev/sdb3) failed -115
#btrfs replace start -Bf /dev/sdb3 /dev/sdb2 /mnt/btrfs
# once you see the error log in dmesg, check return value of
# replace
echo $?
Introduce a new dev replace result
BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS
to catch -EINPROGRESS explicitly and return other errors directly to
userspace.
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
size of @btrfsic_state needs more than 2M, it is very likely to
fail allocating memory using kzalloc(). see following mesage:
[91428.902148] Call Trace:
[<ffffffff816f6e0f>] dump_stack+0x4d/0x66
[<ffffffff811b1c7f>] warn_alloc_failed+0xff/0x170
[<ffffffff811b66e1>] __alloc_pages_nodemask+0x951/0xc30
[<ffffffff811fd9da>] alloc_pages_current+0x11a/0x1f0
[<ffffffff811b1e0b>] ? alloc_kmem_pages+0x3b/0xf0
[<ffffffff811b1e0b>] alloc_kmem_pages+0x3b/0xf0
[<ffffffff811d1018>] kmalloc_order+0x18/0x50
[<ffffffff811d1074>] kmalloc_order_trace+0x24/0x140
[<ffffffffa06c097b>] btrfsic_mount+0x8b/0xae0 [btrfs]
[<ffffffff810af555>] ? check_preempt_curr+0x85/0xa0
[<ffffffff810b2de3>] ? try_to_wake_up+0x103/0x430
[<ffffffffa063d200>] open_ctree+0x1bd0/0x2130 [btrfs]
[<ffffffffa060fdde>] btrfs_mount+0x62e/0x8b0 [btrfs]
[<ffffffff811fd9da>] ? alloc_pages_current+0x11a/0x1f0
[<ffffffff811b0a5e>] ? __get_free_pages+0xe/0x50
[<ffffffff81230429>] mount_fs+0x39/0x1b0
[<ffffffff812509fb>] vfs_kern_mount+0x6b/0x150
[<ffffffff812537fb>] do_mount+0x27b/0xc30
[<ffffffff811b0a5e>] ? __get_free_pages+0xe/0x50
[<ffffffff812544f6>] SyS_mount+0x96/0xf0
[<ffffffff81701970>] system_call_fastpath+0x16/0x1b
Since we are allocating memory for hash table array, so
it will be good if we could allocate continuous pages here.
Fix this problem by firstly trying kzalloc(), if we fail,
use vzalloc() instead.
Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
If cow_file_range_inline() failed, when called from compress_file_range(),
we were tagging the locked page for writeback, end its writeback and unlock it,
but not marking it with an error nor setting AS_EIO in inode's mapping flags.
This made it impossible for a caller of filemap_fdatawrite_range (writepages)
or filemap_fdatawait_range() to know that an error happened. And the return
value of compress_file_range() is useless because it's returned to a workqueue
task and not to the task calling filemap_fdatawrite_range (writepages).
This change applies on top of the previous patchset starting at the patch
titled:
"[1/5] Btrfs: set page and mapping error on compressed write failure"
Which changed extent_clear_unlock_delalloc() to use SetPageError and
mapping_set_error().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
To avoid duplicating this double filemap_fdatawrite_range() call for
inodes with async extents (compressed writes) so often.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
For compressed writes, after doing the first filemap_fdatawrite_range() we
don't get the pages tagged for writeback immediately. Instead we create
a workqueue task, which is run by other kthread, and keep the pages locked.
That other kthread compresses data, creates the respective ordered extent/s,
tags the pages for writeback and unlocks them. Therefore we need a second
call to filemap_fdatawrite_range() if we have compressed writes, as this
second call will wait for the pages to become unlocked, then see they became
tagged for writeback and finally wait for the writeback to finish.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Its return value is useless, its single caller ignores it and can't do
anything with it anyway, since it's a workqueue task and not the task
calling filemap_fdatawrite_range (writepages) nor filemap_fdatawait_range().
Failure is communicated to such functions via start and end of writeback
with the respective pages tagged with an error and AS_EIO flag set in the
inode's imapping.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Steps to reproduce:
# mkfs.btrfs -f /dev/sdb
# mount -t btrfs /dev/sdb /mnt -o compress=lzo
# dd if=/dev/zero of=/mnt/data bs=$((33*4096)) count=1
after previous steps, inode will be detected as bad compression ratio,
and NOCOMPRESS flag will be set for that inode.
Reason is that compress have a max limit pages every time(128K), if a
132k write in, it will be splitted into two write(128k+4k), this bug
is a leftover for commit 68bb462d42a(Btrfs: don't compress for a small write)
Fix this problem by checking every time before compression, if it is a
small write(<=blocksize), we bail out and fall into nocompression directly.
Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Our compressed bio write end callback was essentially ignoring the error
parameter. When a write error happens, it must pass a value of 0 to the
inode's write_page_end_io_hook callback, SetPageError on the respective
pages and set AS_EIO in the inode's mapping flags, so that a call to
filemap_fdatawait_range() / filemap_fdatawait() can find out that errors
happened (we surely don't want silent failures on fsync for example).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Its return value is completely ignored by its single caller and it's
useless anyway, since errors are indicated through SetPageError and
the bit AS_EIO set in the flags of the inode's mapping. The caller
can't do anything with the value, as it's invoked from a workqueue
task and not by the task calling filemap_fdatawrite_range (which calls
the writepages address space callback, which in turn calls the inode's
fill_delalloc callback).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we had an error when processing one of the async extents from our list,
we were not processing the remaining async extents, meaning we would leak
those async_extent structs, never release the pages with the compressed
data and never unlock and clear the dirty flag from the inode's pages (those
that correspond to the uncompressed content).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
In inode.c:submit_compressed_extents(), if we fail before calling
btrfs_submit_compressed_write(), or when that function fails, we
were freeing the async_extent structure without releasing its pages
and freeing the pages array.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
In inode.c:submit_compressed_extents(), before calling btrfs_submit_compressed_write()
we start writeback for all pages, clear their dirty flag, unlock them, etc, but if
btrfs_submit_compressed_write() fails (at the moment it can only fail with -ENOMEM),
we never end the writeback on the pages, so any filemap_fdatawait_range() call will
hang forever. We were also not calling the writepage end io hook, which means the
corresponding ordered extent will never complete and all its waiters will block
forever, such as a full fsync (via btrfs_wait_ordered_range()).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we fail in submit_compressed_extents() before calling btrfs_submit_compressed_write(),
we start and end the writeback for the pages (clear their dirty flag, unlock them, etc)
but we don't tag the pages, nor the inode's mapping, with an error. This makes it
impossible for a caller of filemap_fdatawait_range() (fsync, or transaction commit
for e.g.) know that there was an error.
Note that the return value of submit_compressed_extents() is useless, as that function
is executed by a workqueue task and not directly by the fill_delalloc callback. This
means the writepage/s callbacks of the inode's address space operations don't get that
return value.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The fair reader/writer locks mean that btrfs_clear_path_blocking needs
to strictly follow lock ordering rules even when we already have
blocking locks on a given path.
Before we can clear a blocking lock on the path, we need to make sure
all of the locks have been converted to blocking. This will remove lock
inversions against anyone spinning in write_lock() against the buffers
we're trying to get read locks on. These inversions didn't exist before
the fair read/writer locks, but now we need to be more careful.
We papered over this deadlock in the past by changing
btrfs_try_read_lock() to be a true trylock against both the spinlock and
the blocking lock. This was slower, and not sufficient to fix all the
deadlocks. This patch adds a btrfs_tree_read_lock_atomic(), which
basically means get the spinlock but trylock on the blocking lock.
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reported-by: Patrick Schmid <schmid@phys.ethz.ch>
cc: stable@vger.kernel.org #v3.15+
In some contexts, like in sysfs handlers, we don't want to trigger a
transaction commit. It's a heavy operation, we don't know what external
locks may be taken. Instead, make it possible to finish the operation
through sync syscall or SYNC_FS ioctl.
Signed-off-by: David Sterba <dsterba@suse.cz>
The pending mount option(s) now share namespace and bits with the normal
options, and the existing one for (inode_cache) is unset unconditionally
at each transaction commit.
Introduce a separate namespace for pending changes and enhance the
descriptions of the intended change to use separate bits for each
action.
Signed-off-by: David Sterba <dsterba@suse.cz>
If a pending change is requested, it's not processed unless there is a
transaction commit about to happen, not even after sync or SYNC_FS
ioctl. For example a remount that toggles the inode_cache option will
not take effect after sync on a quiescent filesystem.
Signed-off-by: David Sterba <dsterba@suse.cz>
There are some actions that modify global filesystem state but cannot be
performed at the time of request, but later at the transaction commit
time when the filesystem is in a known state.
For example enabling new incompat features on-the-fly or issuing
transaction commit from unsafe contexts (sysfs handlers).
Signed-off-by: David Sterba <dsterba@suse.cz>
Pull btrfs fix from Chris Mason:
"It's a one liner for an error cleanup path that leads to crashes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix kfree on list_head in btrfs_lookup_csums_range error cleanup
If we hit any errors in btrfs_lookup_csums_range, we'll loop through all
the csums we allocate and free them. But the code was using list_entry
incorrectly, and ended up trying to free the on-stack list_head instead.
This bug came from commit 0678b6185
btrfs: Don't BUG_ON kzalloc error in btrfs_lookup_csums_range()
Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: Erik Berg <btrfs@slipsprogrammoer.no>
cc: stable@vger.kernel.org # 3.3 or newer
Pull btrfs fixes from Chris Mason:
"Filipe is nailing down some problems with our skinny extent variation,
and Dave's patch fixes endian problems in the new super block checks"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix race that makes btrfs_lookup_extent_info miss skinny extent items
Btrfs: properly clean up btrfs_end_io_wq_cache
Btrfs: fix invalid leaf slot access in btrfs_lookup_extent()
btrfs: use macro accessors in superblock validation checks
We have a race that can lead us to miss skinny extent items in the function
btrfs_lookup_extent_info() when the skinny metadata feature is enabled.
So basically the sequence of steps is:
1) We search in the extent tree for the skinny extent, which returns > 0
(not found);
2) We check the previous item in the returned leaf for a non-skinny extent,
and we don't find it;
3) Because we didn't find the non-skinny extent in step 2), we release our
path to search the extent tree again, but this time for a non-skinny
extent key;
4) Right after we released our path in step 3), a skinny extent was inserted
in the extent tree (delayed refs were run) - our second extent tree search
will miss it, because it's not looking for a skinny extent;
5) After the second search returned (with ret > 0), we look for any delayed
ref for our extent's bytenr (and we do it while holding a read lock on the
leaf), but we won't find any, as such delayed ref had just run and completed
after we released out path in step 3) before doing the second search.
Fix this by removing completely the path release and re-search logic. This is
safe, because if we seach for a metadata item and we don't find it, we have the
guarantee that the returned leaf is the one where the item would be inserted,
and so path->slots[0] > 0 and path->slots[0] - 1 must be the slot where the
non-skinny extent item is if it exists. The only case where path->slots[0] is
zero is when there are no smaller keys in the tree (i.e. no left siblings for
our leaf), in which case the re-search logic isn't needed as well.
This race has been present since the introduction of skinny metadata (change
3173a18f70).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
In one of Dave's cleanup commits he forgot to call btrfs_end_io_wq_exit on
unload, which makes us unable to unload and then re-load the btrfs module. This
fixes the problem. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we couldn't find our extent item, we accessed the current slot
(path->slots[0]) to check if it corresponds to an equivalent skinny
metadata item. However this slot could be beyond our last item in the
leaf (i.e. path->slots[0] >= btrfs_header_nritems(leaf)), in which case
we shouldn't process it.
Since btrfs_lookup_extent() is only used to find extent items for data
extents, fix this by removing completely the logic that looks up for an
equivalent skinny metadata item, since it can not exist.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The initial patch c926093ec5 (btrfs: add more superblock checks)
did not properly use the macro accessors that wrap endianness and the
code would not work correctly on big endian machines.
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
It's already duplicated in btrfs and about to be used in overlayfs too.
Move the sticky bit check to an inline helper and call the out-of-line
helper only in the unlikly case of the sticky bit being set.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Pull btrfs data corruption fix from Chris Mason:
"I'm testing a pull with more fixes, but wanted to get this one out so
Greg can pick it up.
The corruption isn't easy to hit, you have to do a readonly snapshot
and have orphans in the snapshot. But my review and testing missed
the bug. Filipe has added a better xfstest to cover it"
* 'for-linus-update' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Revert "Btrfs: race free update of commit root for ro snapshots"
Pull core block layer changes from Jens Axboe:
"This is the core block IO pull request for 3.18. Apart from the new
and improved flush machinery for blk-mq, this is all mostly bug fixes
and cleanups.
- blk-mq timeout updates and fixes from Christoph.
- Removal of REQ_END, also from Christoph. We pass it through the
->queue_rq() hook for blk-mq instead, freeing up one of the request
bits. The space was overly tight on 32-bit, so Martin also killed
REQ_KERNEL since it's no longer used.
- blk integrity updates and fixes from Martin and Gu Zheng.
- Update to the flush machinery for blk-mq from Ming Lei. Now we
have a per hardware context flush request, which both cleans up the
code should scale better for flush intensive workloads on blk-mq.
- Improve the error printing, from Rob Elliott.
- Backing device improvements and cleanups from Tejun.
- Fixup of a misplaced rq_complete() tracepoint from Hannes.
- Make blk_get_request() return error pointers, fixing up issues
where we NULL deref when a device goes bad or missing. From Joe
Lawrence.
- Prep work for drastically reducing the memory consumption of dm
devices from Junichi Nomura. This allows creating clone bio sets
without preallocating a lot of memory.
- Fix a blk-mq hang on certain combinations of queue depths and
hardware queues from me.
- Limit memory consumption for blk-mq devices for crash dump
scenarios and drivers that use crazy high depths (certain SCSI
shared tag setups). We now just use a single queue and limited
depth for that"
* 'for-3.18/core' of git://git.kernel.dk/linux-block: (58 commits)
block: Remove REQ_KERNEL
blk-mq: allocate cpumask on the home node
bio-integrity: remove the needless fail handle of bip_slab creating
block: include func name in __get_request prints
block: make blk_update_request print prefix match ratelimited prefix
blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio
block: fix alignment_offset math that assumes io_min is a power-of-2
blk-mq: Make bt_clear_tag() easier to read
blk-mq: fix potential hang if rolling wakeup depth is too high
block: add bioset_create_nobvec()
block: use bio_clone_fast() in blk_rq_prep_clone()
block: misplaced rq_complete tracepoint
sd: Honor block layer integrity handling flags
block: Replace strnicmp with strncasecmp
block: Add T10 Protection Information functions
block: Don't merge requests if integrity flags differ
block: Integrity checksum flag
block: Relocate bio integrity flags
block: Add a disk flag to block integrity profile
block: Add prefix to block integrity profile flags
...
This reverts commit 9c3b306e1c.
Switching only one commit root during a transaction is wrong because it
leads the fs into an inconsistent state. All commit roots should be
switched at once, at transaction commit time, otherwise backref walking
can often miss important references that were only accessible through
the old commit root. Plus, the root item for the snapshot's root wasn't
getting updated and preventing the next transaction commit to do it.
This made several users get into random corruption issues after creation
of readonly snapshots.
A regression test for xfstests will follow soon.
Cc: stable@vger.kernel.org # 3.17
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch instead allocates the appropriate amount of
memory using a char array using the SHASH_DESC_ON_STACK macro.
The new code can be compiled with both gcc and clang.
Signed-off-by: Vinícius Tinti <viniciustinti@gmail.com>
Reviewed-by: Jan-Simon Möller <dl9pf@gmx.de>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Acked-by: Chris Mason <clm@fb.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Pull vfs updates from Al Viro:
"The big thing in this pile is Eric's unmount-on-rmdir series; we
finally have everything we need for that. The final piece of prereqs
is delayed mntput() - now filesystem shutdown always happens on
shallow stack.
Other than that, we have several new primitives for iov_iter (Matt
Wilcox, culled from his XIP-related series) pushing the conversion to
->read_iter()/ ->write_iter() a bit more, a bunch of fs/dcache.c
cleanups and fixes (including the external name refcounting, which
gives consistent behaviour of d_move() wrt procfs symlinks for long
and short names alike) and assorted cleanups and fixes all over the
place.
This is just the first pile; there's a lot of stuff from various
people that ought to go in this window. Starting with
unionmount/overlayfs mess... ;-/"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (60 commits)
fs/file_table.c: Update alloc_file() comment
vfs: Deduplicate code shared by xattr system calls operating on paths
reiserfs: remove pointless forward declaration of struct nameidata
don't need that forward declaration of struct nameidata in dcache.h anymore
take dname_external() into fs/dcache.c
let path_init() failures treated the same way as subsequent link_path_walk()
fix misuses of f_count() in ppp and netlink
ncpfs: use list_for_each_entry() for d_subdirs walk
vfs: move getname() from callers to do_mount()
gfs2_atomic_open(): skip lookups on hashed dentry
[infiniband] remove pointless assignments
gadgetfs: saner API for gadgetfs_create_file()
f_fs: saner API for ffs_sb_create_file()
jfs: don't hash direct inode
[s390] remove pointless assignment of ->f_op in vmlogrdr ->open()
ecryptfs: ->f_op is never NULL
android: ->f_op is never NULL
nouveau: __iomem misannotations
missing annotation in fs/file.c
fs: namespace: suppress 'may be used uninitialized' warnings
...
Pull btrfs updates from Chris Mason:
"The largest set of changes here come from Miao Xie. He's cleaning up
and improving read recovery/repair for raid, and has a number of
related fixes.
I've merged another set of fsync fixes from Filipe, and he's also
improved the way we handle metadata write errors to make sure we force
the FS readonly if things go wrong.
Otherwise we have a collection of fixes and cleanups. Dave Sterba
gets a cookie for removing the most lines (thanks Dave)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (139 commits)
btrfs: Fix compile error when CONFIG_SECURITY is not set.
Btrfs: fix compiles when CONFIG_BTRFS_FS_RUN_SANITY_TESTS is off
btrfs: Make btrfs handle security mount options internally to avoid losing security label.
Btrfs: send, don't delay dir move if there's a new parent inode
btrfs: add more superblock checks
Btrfs: fix race in WAIT_SYNC ioctl
Btrfs: be aware of btree inode write errors to avoid fs corruption
Btrfs: remove redundant btrfs_verify_qgroup_counts declaration.
btrfs: fix shadow warning on cmp
Btrfs: fix compilation errors under DEBUG
Btrfs: fix crash of btrfs_release_extent_buffer_page
Btrfs: add missing end_page_writeback on submit_extent_page failure
btrfs: Fix the wrong condition judgment about subset extent map
Btrfs: fix build_backref_tree issue with multiple shared blocks
Btrfs: cleanup error handling in build_backref_tree
btrfs: move checks for DUMMY_ROOT into a helper
btrfs: new define for the inline extent data start
btrfs: kill extent_buffer_page helper
btrfs: drop constant param from btrfs_release_extent_buffer_page
btrfs: hide typecast to definition of BTRFS_SEND_TRANS_STUB
...
Pull percpu updates from Tejun Heo:
"A lot of activities on percpu front. Notable changes are...
- percpu allocator now can take @gfp. If @gfp doesn't contain
GFP_KERNEL, it tries to allocate from what's already available to
the allocator and a work item tries to keep the reserve around
certain level so that these atomic allocations usually succeed.
This will replace the ad-hoc percpu memory pool used by
blk-throttle and also be used by the planned blkcg support for
writeback IOs.
Please note that I noticed a bug in how @gfp is interpreted while
preparing this pull request and applied the fix 6ae833c7fe
("percpu: fix how @gfp is interpreted by the percpu allocator")
just now.
- percpu_ref now uses longs for percpu and global counters instead of
ints. It leads to more sparse packing of the percpu counters on
64bit machines but the overhead should be negligible and this
allows using percpu_ref for refcnting pages and in-memory objects
directly.
- The switching between percpu and single counter modes of a
percpu_ref is made independent of putting the base ref and a
percpu_ref can now optionally be initialized in single or killed
mode. This allows avoiding percpu shutdown latency for cases where
the refcounted objects may be synchronously created and destroyed
in rapid succession with only a fraction of them reaching fully
operational status (SCSI probing does this when combined with
blk-mq support). It's also planned to be used to implement forced
single mode to detect underflow more timely for debugging.
There's a separate branch percpu/for-3.18-consistent-ops which cleans
up the duplicate percpu accessors. That branch causes a number of
conflicts with s390 and other trees. I'll send a separate pull
request w/ resolutions once other branches are merged"
* 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (33 commits)
percpu: fix how @gfp is interpreted by the percpu allocator
blk-mq, percpu_ref: start q->mq_usage_counter in atomic mode
percpu_ref: make INIT_ATOMIC and switch_to_atomic() sticky
percpu_ref: add PERCPU_REF_INIT_* flags
percpu_ref: decouple switching to percpu mode and reinit
percpu_ref: decouple switching to atomic mode and killing
percpu_ref: add PCPU_REF_DEAD
percpu_ref: rename things to prepare for decoupling percpu/atomic mode switch
percpu_ref: replace pcpu_ prefix with percpu_
percpu_ref: minor code and comment updates
percpu_ref: relocate percpu_ref_reinit()
Revert "blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during probe"
Revert "percpu: free percpu allocation info for uniprocessor system"
percpu-refcount: make percpu_ref based on longs instead of ints
percpu-refcount: improve WARN messages
percpu: fix locking regression in the failure path of pcpu_alloc()
percpu-refcount: add @gfp to percpu_ref_init()
proportions: add @gfp to init functions
percpu_counter: add @gfp to percpu_counter_init()
percpu_counter: make percpu_counters_lock irq-safe
...
Now that d_invalidate can no longer fail, stop returning a useless
return code. For the few callers that checked the return code update
remove the handling of d_invalidate failure.
Reviewed-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Fix the following compile error when CONFIG_SECURITY is not set:
error: 'struct security_mnt_opts' has no member named 'num_mnt_opts'
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit fccb84c94 moved added some helpers to cleanup our sanity tests,
but it looks like both Dave and I always compile with the tests enabled.
This fixes things to work when they are turned off too.
Signed-off-by: Chris Mason <clm@fb.com>
[BUG]
Originally when mount btrfs with "-o subvol=" mount option, btrfs will
lose all security lable.
And if the btrfs fs is mounted somewhere else, due to the lost of
security lable, SELinux will refuse to mount since the same super block
is being mounted using different security lable.
[REPRODUCER]
With SELinux enabled:
#mkfs -t btrfs /dev/sda5
#mount -o context=system_u:object_r:nfs_t:s0 /dev/sda5 /mnt/btrfs
#btrfs subvolume create /mnt/btrfs/subvol
#mount -o subvol=subvol,context=system_u:object_r:nfs_t:s0 /dev/sda5
/mnt/test
kernel message:
SELinux: mount invalid. Same superblock, different security settings
for (dev sda5, type btrfs)
[REASON]
This happens because btrfs will call vfs_kern_mount() and then
mount_subtree() to handle subvolume name lookup.
First mount will cut off all the security lables and when it comes to
the second vfs_kern_mount(), it has no security label now.
[FIX]
This patch will makes btrfs behavior much more like nfs,
which has the type flag FS_BINARY_MOUNTDATA,
making btrfs handles the security label internally.
So security label will be set in the real mount time and won't lose
label when use with "subvol=" mount option.
Reported-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
If between two snapshots we rename an existing directory named X to Y and
make it a child (direct or not) of a new inode named X, we were delaying
the move/rename of the former directory unnecessarily, which would result
in attempting to rename the new directory from its orphan name to name X
prematurely.
Minimal reproducer:
$ mkfs.btrfs -f /dev/vdd
$ mount /dev/vdd /mnt
$ mkdir -p /mnt/merlin/RC/OSD/Source
$ btrfs subvolume snapshot -r /mnt /mnt/mysnap1
$ mkdir /mnt/OSD
$ mv /mnt/merlin/RC/OSD /mnt/OSD/OSD-Plane_788
$ mv /mnt/OSD /mnt/merlin/RC
$ btrfs subvolume snapshot -r /mnt /mnt/mysnap2
$ btrfs send /mnt/mysnap1 -f /tmp/1.snap
$ btrfs send -p /mnt/mysnap1 /mnt/mysnap2 -f /tmp/2.snap
$ mkfs.btrfs -f /dev/vdc
$ mount /dev/vdc /mnt2
$ btrfs receive /mnt2 -f /tmp/1.snap
$ btrfs receive /mnt2 -f /tmp/2.snap
The second receive (from an incremental send) failed with the following
error message: "rename o261-7-0 -> merlin/RC/OSD failed".
This is a regression introduced in the 3.16 kernel.
A test case for xfstests follows.
Reported-by: Marc Merlin <marc@merlins.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Populate btrfs_check_super_valid() with checks that try to verify
consistency of superblock by additional conditions that may arise from
corrupted devices or bitflips. Some of tests are only hints and issue
warnings instead of failing the mount, basically when the checks are
derived from the data found in the superblock.
Tested on a broken image provided by Qu.
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
We check whether transid is already committed via last_trans_committed and
then search through trans_list for pending transactions. If
last_trans_committed is updated by btrfs_commit_transaction after we check
it (there is no locking), we will fail to find the committed transaction
and return EINVAL to the caller. This has been observed occasionally by
ceph-osd (which uses this ioctl heavily).
Fix by rechecking whether the provided transid <= last_trans_committed
after the search fails, and if so return 0.
Signed-off-by: Sage Weil <sage@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
While we have a transaction ongoing, the VM might decide at any time
to call btree_inode->i_mapping->a_ops->writepages(), which will start
writeback of dirty pages belonging to btree nodes/leafs. This call
might return an error or the writeback might finish with an error
before we attempt to commit the running transaction. If this happens,
we might have no way of knowing that such error happened when we are
committing the transaction - because the pages might no longer be
marked dirty nor tagged for writeback (if a subsequent modification
to the extent buffer didn't happen before the transaction commit) which
makes filemap_fdata[write|wait]_range unable to find such pages (even
if they're marked with SetPageError).
So if this happens we must abort the transaction, otherwise we commit
a super block with btree roots that point to btree nodes/leafs whose
content on disk is invalid - either garbage or the content of some
node/leaf from a past generation that got cowed or deleted and is no
longer valid (for this later case we end up getting error messages like
"parent transid verify failed on 10826481664 wanted 25748 found 29562"
when reading btree nodes/leafs from disk).
Note that setting and checking AS_EIO/AS_ENOSPC in the btree inode's
i_mapping would not be enough because we need to distinguish between
log tree extents (not fatal) vs non-log tree extents (fatal) and
because the next call to filemap_fdatawait_range() will catch and clear
such errors in the mapping - and that call might be from a log sync and
not from a transaction commit, which means we would not know about the
error at transaction commit time. Also, checking for the eb flag
EXTENT_BUFFER_IOERR at transaction commit time isn't done and would
not be completely reliable, as the eb might be removed from memory and
read back when trying to get it, which clears that flag right before
reading the eb's pages from disk, making us not know about the previous
write error.
Using the new 3 flags for the btree inode also makes us achieve the
goal of AS_EIO/AS_ENOSPC when writepages() returns success, started
writeback for all dirty pages and before filemap_fdatawait_range() is
called, the writeback for all dirty pages had already finished with
errors - because we were not using AS_EIO/AS_ENOSPC,
filemap_fdatawait_range() would return success, as it could not know
that writeback errors happened (the pages were no longer tagged for
writeback).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Do like disk-io function declared under CONFIG_BTRFS_FS_RUN_SANITY_TESTS
and keep prototype in qgroup.h only
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Chris Mason <clm@fb.com>
cmp was declared twice in btrfs_compare_trees resulting in a shadow
warning. This patch renames second internal variable.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Chris Mason <clm@fb.com>
bi_sector and bi_size moved to bi_iter since commit 4f024f3797
("block: Abstract out bvec iterator")
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Chris Mason <clm@fb.com>
This is actually inspired by Filipe's patch. When write_one_eb() fails on
submit_extent_page(), it'll give up writing this eb and mark it with
EXTENT_BUFFER_IOERR. So if it's not the last page that encounter the failure,
there are some left pages which remain DIRTY, and if a later COW on this eb
happens, ie. eb is COWed and freed, it'd run into BUG_ON in
btrfs_release_extent_buffer_page() for the DIRTY page, ie. BUG_ON(PageDirty(page));
This adds the missing clear_page_dirty_for_io() for the rest pages of eb.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If submit_extent_page() fails in write_one_eb(), we end up with the current
page not marked dirty anymore, unlocked and marked for writeback. But we never
end up calling end_page_writeback() against the page, which will make calls to
filemap_fdatawait_range (e.g. at transaction commit time) hang forever waiting
for the writeback bit to be cleared from the page.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Previous commit: btrfs: Fix and enhance merge_extent_mapping() to insert
best fitted extent map
is using wrong condition to judgement whether the range is a subset of a
existing extent map.
This may cause bug in btrfs no-holes mode.
This patch will correct the judgment and fix the bug.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Marc Merlin sent me a broken fs image months ago where it would blow up in the
upper->checked BUG_ON() in build_backref_tree. This is because we had a
scenario like this
block a -- level 4 (not shared)
|
block b -- level 3 (reloc block, shared)
|
block c -- level 2 (not shared)
|
block d -- level 1 (shared)
|
block e -- level 0 (shared)
We go to build a backref tree for block e, we notice block d is shared and add
it to the list of blocks to lookup it's backrefs for. Now when we loop around
we will check edges for the block, so we will see we looked up block c last
time. So we lookup block d and then see that the block that points to it is
block c and we can just skip that edge since we've already been up this path.
The problem is because we clear need_check when we see block d (as it is shared)
we never add block b as needing to be checked. And because block c is in our
path already we bail out before we walk up to block b and add it to the backref
check list.
To fix this we need to reset need_check if we trip over a block that doesn't
need to be checked. This will make sure that any subsequent blocks in the path
as we're walking up afterwards are added to the list to be processed. With this
patch I can now mount Marc's fs image and it'll complete the balance without
panicing. Thanks,
Reported-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
When balance panics it tends to panic in the
BUG_ON(!upper->checked);
test, because it means it couldn't build the backref tree properly. This is
annoying to users and frankly a recoverable error, nothing in this function is
actually fatal since it is just an in-memory building of the backrefs for a
given bytenr. So go through and change all the BUG_ON()'s to ASSERT()'s, and
fix the BUG_ON(!upper->checked) thing to just return an error.
This patch also fixes the error handling so it tears down the work we've done
properly. This code was horribly broken since we always just panic'ed instead
of actually erroring out, so it needed to be completely re-worked. With this
patch my broken image no longer panics when I mount it. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Use a common definition for the inline data start so we don't have to
open-code it and introduce bugs like "Btrfs: fix wrong max inline data
size limit" fixed.
Signed-off-by: David Sterba <dsterba@suse.cz>
8MiB is way too large and likely set by mistake. This is not
a significant issue as in practice the max amount of data
added to an inline extent is also limited by the page cache
and btree leaf sizes.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: David Sterba <dsterba@suse.cz>
Rename to btrfs_alloc_tree_block as it fits to the alloc/find/free +
_tree_block family. The parameter blocksize was set to the metadata
block size, directly or indirectly.
Signed-off-by: David Sterba <dsterba@suse.cz>
The parent_transid parameter has been unused since its introduction in
ca7a79ad8d ("Pass down the expected generation number when reading
tree blocks"). In reada_tree_block, it was even wrongly set to leafsize.
Transid check is done in the proper read and readahead ignores errors.
Signed-off-by: David Sterba <dsterba@suse.cz>
There are the branch hints that obviously depend on the data being
processed, the CPU predictor will do better job according to the actual
load. It also does not make sense to use the hints in slow paths that do
a lot of other operations like locking, waiting or IO.
Signed-off-by: David Sterba <dsterba@suse.cz>
This is to receive 0a30288da1 ("blk-mq, percpu_ref: implement a
kludge for SCSI blk-mq stall during probe") which implements
__percpu_ref_kill_expedited() to work around SCSI blk-mq stall. The
commit reverted and patches to implement proper fix will be added.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
When doing log replay we may have to update inodes, which traditionally goes
through our delayed inode stuff. This will try to move space over from the
trans handle, but we don't reserve space in our trans handle on replay since we
don't know how much we will need, so instead we try to flush. But because we
have a trans handle open we won't flush anything, so if we are out of reserve
space we will simply return ENOSPC. Since we know that if an operation made it
into the log then we definitely had space before the box bought the farm then we
don't need to worry about doing this space reservation. Use the
fs_info->log_root_recovering flag to skip the delayed inode stuff and update the
item directly. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Trying to reproduce a log enospc bug I hit a panic in the async reclaim code
during log replay. This is because we use fs_info->fs_root as our root for
shrinking and such. Technically we can use whatever root we want, but let's
just not allow async reclaim while we're doing log replay. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
One problem that has plagued us is that a user will use up all of his space with
data, remove a bunch of that data, and then try to create a bunch of small files
and run out of space. This happens because all the chunks were allocated for
data since the metadata requirements were so low. But now there's a bunch of
empty data block groups and not enough metadata space to do anything. This
patch solves this problem by automatically deleting empty block groups. If we
notice the used count go down to 0 when deleting or on mount notice that a block
group has a used count of 0 then we will queue it to be deleted.
When the cleaner thread runs we will double check to make sure the block group
is still empty and then we will delete it. This patch has the side effect of no
longer having a bunch of BUG_ON()'s in the chunk delete code, which will be
helpful for both this and relocate. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"I've got a revert to fix a regression with btrfs device registration,
and Filipe has part two of his fsync fix from last week"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Revert "Btrfs: device_list_add() should not update list when mounted"
Btrfs: set inode's logged_trans/last_log_commit after ranged fsync
When we do a fast fsync, we start all ordered operations and then while
they're running in parallel we visit the list of modified extent maps
and construct their matching file extent items and write them to the
log btree. After that, in btrfs_sync_log() we wait for all the ordered
operations to finish (via btrfs_wait_logged_extents).
The problem with this is that we were completely ignoring errors that
can happen in the extent write path, such as -ENOSPC, a temporary -ENOMEM
or -EIO errors for example. When such error happens, it means we have parts
of the on disk extent that weren't written to, and so we end up logging
file extent items that point to these extents that contain garbage/random
data - so after a crash/reboot plus log replay, we get our inode's metadata
pointing to those extents.
This worked in contrast with the full (non-fast) fsync path, where we
start all ordered operations, wait for them to finish and then write
to the log btree. In this path, after each ordered operation completes
we check if it's flagged with an error (BTRFS_ORDERED_IOERR) and return
-EIO if so (via btrfs_wait_ordered_range).
So if an error happens with any ordered operation, just return a -EIO
error to userspace, so that it knows that not all of its previous writes
were durably persisted and the application can take proper action (like
redo the writes for e.g.) - and definitely not leave any file extent items
in the log refer to non fully written extents.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When the fsync callback (btrfs_sync_file) starts, it first waits for
the writeback of any dirty pages to start and finish without holding
the inode's mutex (to reduce contention). After this it acquires the
inode's mutex and repeats that process via btrfs_wait_ordered_range
only if we're doing a full sync (BTRFS_INODE_NEEDS_FULL_SYNC flag
is set on the inode).
This is not safe for a non full sync - we need to start and wait for
writeback to finish for any pages that might have been made dirty
before acquiring the inode's mutex and after that first step mentioned
before. Why this is needed is explained by the following comment added
to btrfs_sync_file:
"Right before acquiring the inode's mutex, we might have new
writes dirtying pages, which won't immediately start the
respective ordered operations - that is done through the
fill_delalloc callbacks invoked from the writepage and
writepages address space operations. So make sure we start
all ordered operations before starting to log our inode. Not
doing this means that while logging the inode, writeback
could start and invoke writepage/writepages, which would call
the fill_delalloc callbacks (cow_file_range,
submit_compressed_extents). These callbacks add first an
extent map to the modified list of extents and then create
the respective ordered operation, which means in
tree-log.c:btrfs_log_inode() we might capture all existing
ordered operations (with btrfs_get_logged_extents()) before
the fill_delalloc callback adds its ordered operation, and by
the time we visit the modified list of extent maps (with
btrfs_log_changed_extents()), we see and process the extent
map they created. We then use the extent map to construct a
file extent item for logging without waiting for the
respective ordered operation to finish - this file extent
item points to a disk location that might not have yet been
written to, containing random data - so after a crash a log
replay will make our inode have file extent items that point
to disk locations containing invalid data, as we returned
success to userspace without waiting for the respective
ordered operation to finish, because it wasn't captured by
btrfs_get_logged_extents()."
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
This reverts commit b96de000bc.
This commit is triggering failures to mount by subvolume id in some
configurations. The main problem is how many different ways this
scanning function is used, both for scanning while mounted and
unmounted. A proper cleanup is too big for late rcs.
For now, just revert the commit and we'll put a better fix into a later
merge window.
Signed-off-by: Chris Mason <clm@fb.com>
The following commit enhanced the merge_extent_mapping() to reduce
fragment in extent map tree, but it can't handle case which existing
lies before map_start:
51f39 btrfs: Use right extent length when inserting overlap extent map.
[BUG]
When existing extent map's start is before map_start,
the em->len will be minus, which will corrupt the extent map and fail to
insert the new extent map.
This will happen when someone get a large extent map, but when it is
going to insert it into extent map tree, some one has already commit
some write and split the huge extent into small parts.
[REPRODUCER]
It is very easy to tiger using filebench with randomrw personality.
It is about 100% to reproduce when using 8G preallocated file in 60s
randonrw test.
[FIX]
This patch can now handle any existing extent position.
Since it does not directly use existing->start, now it will find the
previous and next extent around map_start.
So the old existing->start < map_start bug will never happen again.
[ENHANCE]
This patch will insert the best fitted extent map into extent map tree,
other than the oldest [map_start, map_start + sectorsize) or the
relatively newer but not perfect [map_start, existing->start).
The patch will first search existing extent that does not intersects with
the desired map range [map_start, map_start + len).
The existing extent will be either before or behind map_start, and based
on the existing extent, we can find out the previous and next extent
around map_start.
So the best fitted extent would be [prev->end, next->start).
For prev or next is not found, em->start would be prev->end and em->end
wold be next->start.
With this patch, the fragment in extent map tree should be reduced much
more than the 51f39 commit and reduce an unneeded extent map tree search.
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
An user reported this, it is because that lseek's SEEK_SET/SEEK_CUR/SEEK_END
allow a negative value for @offset, but btrfs's SEEK_DATA/SEEK_HOLE don't
prepare for that and convert the negative @offset into unsigned type,
so we get (end < start) warning.
[ 1269.835374] ------------[ cut here ]------------
[ 1269.836809] WARNING: CPU: 0 PID: 1241 at fs/btrfs/extent_io.c:430 insert_state+0x11d/0x140()
[ 1269.838816] BTRFS: end < start 4094 18446744073709551615
[ 1269.840334] CPU: 0 PID: 1241 Comm: a.out Tainted: G W 3.16.0+ #306
[ 1269.858229] Call Trace:
[ 1269.858612] [<ffffffff81801a69>] dump_stack+0x4e/0x68
[ 1269.858952] [<ffffffff8107894c>] warn_slowpath_common+0x8c/0xc0
[ 1269.859416] [<ffffffff81078a36>] warn_slowpath_fmt+0x46/0x50
[ 1269.859929] [<ffffffff813b0fbd>] insert_state+0x11d/0x140
[ 1269.860409] [<ffffffff813b1396>] __set_extent_bit+0x3b6/0x4e0
[ 1269.860805] [<ffffffff813b21c7>] lock_extent_bits+0x87/0x200
[ 1269.861697] [<ffffffff813a5b28>] btrfs_file_llseek+0x148/0x2a0
[ 1269.862168] [<ffffffff811f201e>] SyS_lseek+0xae/0xc0
[ 1269.862620] [<ffffffff8180b212>] system_call_fastpath+0x16/0x1b
[ 1269.862970] ---[ end trace 4d33ea885832054b ]---
This assumes that btrfs starts finding DATA/HOLE from the beginning of file
if the assigned @offset is negative.
Also we add alignment for lock_extent_bits 's range.
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
After the data is written successfully, we should cleanup the read failure record
in that range because
- If we set data COW for the file, the range that the failure record pointed to is
mapped to a new place, so it is invalid.
- If we set no data COW for the file, and if there is no error during writting,
the corrupted data is corrected, so the failure record can be removed. And if
some errors happen on the mirrors, we also needn't worry about it because the
failure record will be recreated if we read the same place again.
Sometimes, we may fail to correct the data, so the failure records will be left
in the tree, we need free them when we free the inode or the memory leak happens.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This patch implement data repair function when direct read fails.
The detail of the implementation is:
- When we find the data is not right, we try to read the data from the other
mirror.
- When the io on the mirror ends, we will insert the endio work into the
dedicated btrfs workqueue, not common read endio workqueue, because the
original endio work is still blocked in the btrfs endio workqueue, if we
insert the endio work of the io on the mirror into that workqueue, deadlock
would happen.
- After we get right data, we write it back to the corrupted mirror.
- And if the data on the new mirror is still corrupted, we will try next
mirror until we read right data or all the mirrors are traversed.
- After the above work, we set the uptodate flag according to the result.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We need real mirror number for RAID0/5/6 when reading data, or if read error
happens, we would pass 0 as the number of the mirror on which the io error
happens. It is wrong and would cause the filesystem read the data from the
corrupted mirror again.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We could not use clean_io_failure in the direct IO path because it got the
filesystem information from the page structure, but the page in the direct
IO bio didn't have the filesystem information in its structure. So we need
modify it and pass all the information it need by parameters.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The original code of repair_io_failure was just used for buffered read,
because it got some filesystem data from page structure, it is safe for
the page in the page cache. But when we do a direct read, the pages in bio
are not in the page cache, that is there is no filesystem data in the page
structure. In order to implement direct read data repair, we need modify
repair_io_failure and pass all filesystem data it need by function
parameters.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The data repair function of direct read will be implemented later, and some code
in bio_readpage_error will be reused, so split bio_readpage_error into
several functions which will be used in direct read repair later.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We forgot to free failure record and bio after submitting re-read bio failed,
fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Direct IO splits the original bio to several sub-bios because of the limit of
raid stripe, and the filesystem will wait for all sub-bios and then run final
end io process.
But it was very hard to implement the data repair when dio read failure happens,
because at the final end io function, we didn't know which mirror the data was
read from. So in order to implement the data repair, we have to move the file data
check in the final end io function to the sub-bio end io function, in which we can
get the mirror number of the device we access. This patch did this work as the
first step of the direct io data repair implementation.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The current code would load checksum data for several times when we split
a whole direct read io because of the limit of the raid stripe, it would
make us search the csum tree for several times. In fact, it just wasted time,
and made the contention of the csum tree root be more serious. This patch
improves this problem by loading the data at once.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
rw_devices counter is often used to tune the profile when doing chunk allocation,
so we should modify it under the chunk_mutex context to avoid getting wrong
chunk profile.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
For a missing device, we don't know it belong to which fs before we read its
fsid from the chunk tree. So we add them into the current fs device list at first.
When we get its fsid, we should move them to their own fs device list.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we open a seed filesystem, if the degraded mount option is set, we continue to
mount the fs if we don't find some devices in the seed filesystem. But we should stop
mounting if other errors happen. Fix it
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The problem is:
Task0(device scan task) Task1(device replace task)
scan_one_device()
mutex_lock(&uuid_mutex)
device = find_device()
mutex_lock(&device_list_mutex)
lock_chunk()
rm_and_free_source_device
unlock_chunk()
mutex_unlock(&device_list_mutex)
check device
Destroying the target device if device replace fails also has the same problem.
We fix this problem by locking uuid_mutex during destroying source device or
target device, just like the device remove operation.
It is a temporary solution, we can fix this problem and make the code more
clear by atomic counter in the future.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We can build a new filesystem based a seed filesystem, and we need clone
the fs devices when we open the new filesystem. But someone might clear
the seed flag of the seed filesystem, then mount that filesystem and
remove some device. If we mount the new filesystem, we might access
a device list which was being changed when we clone the fs devices.
Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
There were several problems about chunk mutex usage:
- Lock chunk mutex when updating metadata. It would cause the nested
deadlock because updating metadata might need allocate new chunks
that need acquire chunk mutex. We remove chunk mutex at this case,
because b-tree lock and other lock mechanism can help us.
- ABBA deadlock occured between device_list_mutex and chunk_mutex.
When we update device status, we must acquire device_list_mutex at the
beginning, and then we might get chunk_mutex during the device status
update because we need allocate new chunks for metadata COW. But at
most place, we acquire chunk_mutex at first and then acquire device list
mutex. We need change the lock order.
- Some place we needn't acquire chunk_mutex. For example we needn't get
chunk_mutex when we free a empty seed fs_devices structure.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we get the fs information, we forgot to acquire the mutex of device list,
it might cause the problem we might access a device that was removed. Fix
it by acquiring the device list mutex.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We didn't protect the system chunk array when we added a new
system chunk into it, it would cause the array be corrupted
if someone remove/add some system chunk into array at the same
time. Fix it by chunk lock.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
->total_bytes,->disk_total_bytes,->bytes_used is protected by chunk
lock when we change them, but sometimes we read them without any lock,
and we might get unexpected value. We fix this problem like inode's
i_size.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We should update free_chunk_space in time when we allocate a new chunk,
not when we deal with the pending device update and block group insertion,
because we need the real free_chunk_space data to calculate the reserved
space, if we don't update it in time, we would consider the disk space which
has be allocated as free space, and would use it to do overcommit reservation.
Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We should update device->bytes_used in the lock context of
chunk_mutex, or we would get wrong data.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
During removing a device, we have modified free_chunk_space when we
shrink the device, so we needn't assign a new value to it after
the device shrink. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
device->bytes_used will be changed when allocating a new chunk, and
disk_total_size will be changed if resizing is successful.
Meanwhile, the on-disk super blocks of the previous transaction
might not be updated. Considering the consistency of the metadata
in the previous transaction, We should use the size in the previous
transaction to check if the super block is beyond the boundary
of the device.
Though it is not big problem because we don't use it now, but anyway
it is better that we make it be consistent with the common metadata,
maybe we will use it in the future.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
total_size will be changed when resizing a device, and disk_total_size
will be changed if resizing is successful. Meanwhile, the on-disk super
blocks of the previous transaction might not be updated. Considering
the consistency of the metadata in the previous transaction, We should
use the size in the previous transaction to check if the super block is
beyond the boundary of the device. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We didn't protect the assignment of the target device, it might cause the
problem that the super block update was skipped because we might find wrong
size of the target device during the assignment. Fix it by moving the
assignment sentences into the initialization function of the target device.
And there is another merit that we can check if the target device is suitable
more early.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The member variants - num_can_discard - of fs_devices structure
are set, but no one use them to do anything. so remove them.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This comments became wrong after c3c532[bdi: add helper function for
doing init and register of a bdi for a file system], so remove them.
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
When replaying a directory from the fsync log, if a directory entry
exists both in the fs/subvol tree and in the log, the directory's inode
got its i_size updated incorrectly, accounting for the dentry's name
twice.
Reproducer, from a test for xfstests:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
touch $SCRATCH_MNT/foo
sync
touch $SCRATCH_MNT/bar
xfs_io -c "fsync" $SCRATCH_MNT
xfs_io -c "fsync" $SCRATCH_MNT/bar
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
[ -f $SCRATCH_MNT/foo ] || echo "file foo is missing"
[ -f $SCRATCH_MNT/bar ] || echo "file bar is missing"
_unmount_flakey
_check_scratch_fs $FLAKEY_DEV
The filesystem check at the end failed with the message:
"root 5 root dir 256 error".
A test case for xfstests follows.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
One of my tests shows that when we really don't have space to reclaim via
flush_space and also run out of space, this async reclaim work loops on adding
itself into the workqueue and keeps writing something to disk according to
iostat's results, and these writes mainly comes from commit_transaction which
writes super_block. This's unacceptable as it can be bad to disks, especially
memeory storages.
This adds a check to avoid the above situation.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
We have been iterating all references for each extent we have in a file when we
do fiemap to see if it is shared. This is fine when you have a few clones or a
few snapshots, but when you have 5k snapshots suddenly fiemap just sits there
and stares at you. So add btrfs_check_shared which will use the backref walking
code but will short circuit as soon as it finds a root or inode that doesn't
match the one we currently have. This makes fiemap on my testbox go from
looking at me blankly for a day to spitting out actual output in a reasonable
amount of time. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The behaviour of a 'chattr -c' consists of getting the current flags,
clearing the FS_COMPR_FL bit and then sending the result to the set
flags ioctl - this means the bit FS_NOCOMP_FL isn't set in the flags
passed to the ioctl. This results in the compression property not being
cleared from the inode - it was cleared only if the bit FS_NOCOMP_FL
was set in the received flags.
Reproducer:
$ mkfs.btrfs -f /dev/sdd
$ mount /dev/sdd /mnt && cd /mnt
$ mkdir a
$ chattr +c a
$ touch a/file
$ lsattr a/file
--------c------- a/file
$ chattr -c a
$ touch a/file2
$ lsattr a/file2
--------c------- a/file2
$ lsattr -d a
---------------- a
Reported-by: Andreas Schneider <asn@cryptomilk.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs-transacion:5657
[stack snip]
btrfs_bio_map()
btrfs_bio_counter_inc_blocked()
percpu_counter_inc(&fs_info->bio_counter) ###bio_counter > 0(A)
__btrfs_bio_map()
btrfs_dev_replace_lock()
mutex_lock(dev_replace->lock) ###wait mutex(B)
btrfs:32612
[stack snip]
btrfs_dev_replace_start()
btrfs_dev_replace_lock()
mutex_lock(dev_replace->lock) ###hold mutex(B)
btrfs_dev_replace_finishing()
btrfs_rm_dev_replace_blocked()
wait until percpu_counter_sum == 0 ###wait on bio_counter(A)
This bug can be triggered quite easily by the following test script:
http://pastebin.com/MQmb37Cy
This patch will fix the ABBA problem by calling
btrfs_dev_replace_unlock() before btrfs_rm_dev_replace_blocked().
The consistency of btrfs devices list and their superblocks is protected
by device_list_mutex, not btrfs_dev_replace_lock/unlock().
So it is safe the move btrfs_dev_replace_unlock() before
btrfs_rm_dev_replace_blocked().
Reported-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Cc: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <clm@fb.com>
We've defined a 'offset' out of bio_for_each_segment_all.
This is just a clean rename, no function changes.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_drop_snapshot() leaves subvolume qgroup items on disk after
completion. This can cause problems with snapshot creation. If a new
snapshot tries to claim the deleted subvolumes id, btrfs will get -EEXIST
from add_qgroup_item() and go read-only. The following commands will
reproduce this problem (assume btrfs is on /dev/sda and is mounted at
/btrfs)
mkfs.btrfs -f /dev/sda
mount -t btrfs /dev/sda /btrfs/
btrfs quota enable /btrfs/
btrfs su sna /btrfs/ /btrfs/snap
btrfs su de /btrfs/snap
sleep 45
umount /btrfs/
mount -t btrfs /dev/sda /btrfs/
We can fix this by catching -EEXIST in add_qgroup_item() and
initializing the existing items. We have the problem of orphaned
relation items being on disk from an old snapshot but that is outside
the scope of this patch.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
The map_start and map_len fields aren't used anywhere, so just remove
them. On a x86_64 system, this reduced sizeof(struct extent_buffer)
from 296 bytes to 280 bytes, and therefore 14 extent_buffer structs can
now fit into a page instead of 13.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Maximum xattr size can be up to nearly the leaf size. For an fs with a
leaf size larger than the page size, using kmalloc requires allocating
multiple pages that are contiguous, which might not be possible if
there's heavy memory fragmentation. Therefore fallback to vmalloc if
we fail to allocate with kmalloc. Also start with a smaller buffer size,
since xattr values typically are smaller than a page.
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Last user removed in commit "btrfs: disable strict file flushes for
renames and truncates" (8d875f95da).
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
While under random IO, a block group's free space cache eventually reaches
a state where it has a mix of extent entries and bitmap entries representing
free space regions.
As later free space regions are returned to the cache, some of them are merged
with existing extent entries if they are contiguous with them. But others are
not merged, because despite the existence of adjacent free space regions in
the cache, the merging doesn't happen because the existing free space regions
are represented in bitmap extents. Even when new free space regions are merged
with existing extent entries (enlarging the free space range they represent),
we create chances of having after an enlarged region that is contiguous with
some other region represented in a bitmap entry.
Both clustered and non-clustered space allocation work by iterating over our
extent and bitmap entries and skipping any that represents a region smaller
then the allocation request (and giving preference to extent entries before
bitmap entries). By having a contiguous free space region that is represented
by 2 (or more) entries (mix of extent and bitmap entries), we end up not
satisfying an allocation request with a size larger than the size of any of
the entries but no larger than the sum of their sizes. Making the caller assume
we're under a ENOSPC condition or force it to allocate multiple smaller space
regions (as we do for file data writes), which adds extra overhead and more
chances of causing fragmentation due to the smaller regions being all spread
apart from each other (more likely when under concurrency).
For example, if we have the following in the cache:
* extent entry representing free space range: [128Mb - 256Kb, 128Mb[
* bitmap entry covering the range [128Mb, 256Mb[, but only with the bits
representing the range [128Mb, 128Mb + 768Kb[ set - that is, only that
space in this 128Mb area is marked as free
An allocation request for 1Mb, starting at offset not greater than 128Mb - 256Kb,
would fail before, despite the existence of such contiguous free space area in the
cache. The caller could only allocate up to 768Kb of space at once and later another
256Kb (or vice-versa). In between each smaller allocation request, another task
working on a different file/inode might come in and take that space, preventing the
former task of getting a contiguous 1Mb region of free space.
Therefore this change implements the ability to move free space from bitmap
entries into existing and new free space regions represented with extent
entries. This is done when a space region is added to the cache.
A test was added to the sanity tests that explains in detail the issue too.
Some performance test results with compilebench on a 4 cores machine, with
32Gb of ram and using an HDD follow.
Test: compilebench -D /mnt -i 30 -r 1000 --makej
Before this change:
intial create total runs 30 avg 69.02 MB/s (user 0.28s sys 0.57s)
compile total runs 30 avg 314.96 MB/s (user 0.12s sys 0.25s)
read compiled tree total runs 3 avg 27.14 MB/s (user 1.52s sys 0.90s)
delete compiled tree total runs 30 avg 3.14 seconds (user 0.15s sys 0.66s)
After this change:
intial create total runs 30 avg 68.37 MB/s (user 0.29s sys 0.55s)
compile total runs 30 avg 382.83 MB/s (user 0.12s sys 0.24s)
read compiled tree total runs 3 avg 27.82 MB/s (user 1.45s sys 0.97s)
delete compiled tree total runs 30 avg 3.18 seconds (user 0.17s sys 0.65s)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
we are assigning number_devices to the total_bytes,
that's very confusing for a moment
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
there is no matching open parenthesis for the closing parenthesis
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
seed fs devices don't participate as rw_device, so don't increment
rw_devices when the device being handled belongs to a seed fs.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we replace all the seed device in the system there is
no point in just keeping the btrfs_fs_devices with out
any device
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
We are not updating sprout fs seed pointer when all seed device
is replaced. This patch will check if all seed device has been
replaced and then update the sprout pointer accordingly.
Same reproducer as in the previous patch would apply here.
And notice that btrfs_close_device will check if seed fs is
present and spits out the error with out this patch.
int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
{
::
seed_devices = fs_devices->seed;
::
while (seed_devices) {
fs_devices = seed_devices;
seed_devices = fs_devices->seed;
__btrfs_close_devices(fs_devices);
free_fs_devices(fs_devices);
}
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
reproducer:
reproducer:
mount /dev/sdb /btrfs
btrfs dev add /dev/sdc /btrfs
btrfs rep start -B /dev/sdb /dev/sdd /btrfs
umount /btrfs
WARNING: CPU: 0 PID: 3882 at fs/btrfs/volumes.c:892 __btrfs_close_devices+0x1c8/0x200 [btrfs]()
which is
WARN_ON(fs_devices->rw_devices);
The problem here is that we did not add one to the rw_devices when
we replace the seed device with a writable device.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
reproducer:
mount /dev/sdb /btrfs
btrfs dev add /dev/sdc /btrfs
btrfs rep start -B /dev/sdb /dev/sdd /btrfs
umount /btrfs
WARNING: CPU: 0 PID: 12661 at fs/btrfs/volumes.c:891 __btrfs_close_devices+0x1b0/0x200 [btrfs]()
::
__btrfs_close_devices()
::
WARN_ON(fs_devices->open_devices);
After the seed device has been replaced the new target device
is no more a seed device. So we need to update the device
numbers in the fs_devices as pointed by the fs_info.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
There is no logical change in this patch, just a preparatory patch,
so that changes can be easily reasoned.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
The issue was introduced in a79b7d4b3e,
adding allocation of extent_workers, so this stray check is surely not
meant to be a check of something else.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=82021
Reported-by: Maks Naumov <maksqwe1@ukr.net>
Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
None of the uses of btrfs_search_forward() need to have the path
nodes (level >= 1) read locked, only the leaf needs to be locked
while the caller processes it. Therefore make it return a path
with all nodes unlocked, except for the leaf.
This change is motivated by the observation that during a file
fsync we repeatdly call btrfs_search_forward() and process the
returned leaf while upper nodes of the returned path (level >= 1)
are read locked, which unnecessarily blocks other tasks that want
to write to the same fs/subvol btree.
Therefore instead of modifying the fsync code to unlock all nodes
with level >= 1 immediately after calling btrfs_search_forward(),
change btrfs_search_forward() to do it, so that it benefits all
callers.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
BTRFS_ATTR_RW could set the mode and be inline with BTRFS_ATTR
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
All that uses BTRFS_ATTR want mode to be set at 0444 so just do
it at the define. And few spacing alignments.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we need to cow a node, increase the write lock level and retry the
tree search, there's no point of changing the node locks in our path
to blocking mode, as we only waste time and unnecessarily wake up other
tasks waiting on the spinning locks (just to block them again shortly
after) because we release our path before repeating the tree search.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
In ctree.c:setup_items_for_insert(), we can unlock all nodes in our
path before we process the leaf (shift items and data, adjust data
offsets, etc). This allows for better btree concurrency, as we're
often holding a write lock on at least the node at level 1.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_lookup_csums_range() uses ALIGN() to check if "start"
and "end + 1" are aligned to "root->sectorsize". It's better to
replace these with IS_ALIGNED() for simplicity.
Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We want this to debug qgroup changes on live systems.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The member variants - latest_devid and latest_trans - of fs_devices structure
are set, but no one use them to do anything. so remove them.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The io error might happen during writing out the device stats, and the
device stats information and dirty flag would be update at that time,
but the current code didn't consider this case, just clear the dirty
flag, it would cause that we forgot to write out the new device stats
information. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The lock in btrfs_device structure was far away from its protected data, it would
make CPU load the cache line twice when we accessed them, move them together.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The super block generation of the seed devices is not the same as the
filesystem which sprouted from them because we don't update the super
block on the seed devices when we change that new filesystem. So we
should not use the generation of that new filesystem to check the super
block generation on the seed devices, Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
All the metadata in the seed devices has the same fsid as the fsid
of the seed filesystem which is on the seed device, so we should check
them by the current filesystem. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The transaction thread may want to do more work, namely it pokes the
cleaner ktread that will start processing uncleaned subvols.
This can be triggered by user via the 'btrfs fi sync' command, otherwise
there was a delay up to 30 seconds before the cleaner started to clean
old snapshots.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
inline data is stored from offset of @disk_bytenr in
struct btrfs_file_extent_item. So substracting total
size of struct btrfs_file_extent_item is wrong, fix it.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Btrfs could still inline file data if its size is same as
page size, so don't skip max value here.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
If flag NOCOMPRESS is set which means bad compression ratio,
we could avoid call cow_file_range_async() for this case earlier.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
If a file's compression ratios is bad, we will set NOCOMPRESS
flag for it, and it will skip compression for that inode next time.
However, if we remount fs to COMPRESS_FORCE, it still should try
if we could compress pages for that inode, this patch fix wrong
check for this problem.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Fix the following sparse warning:
fs/btrfs/send.c:518:51: warning: incorrect type in argument 2 (different address spaces)
fs/btrfs/send.c:518:51: expected char const [noderef] <asn:1>*<noident>
fs/btrfs/send.c:518:51: got char *
We can safely use (const char __user *) with set_fs(KERNEL_DS)
__force added to avoid sparse-all warning:
fs/btrfs/send.c:518:40: warning: cast adds address space to expression (<asn:1>)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Chris Mason <clm@fb.com>
Use BUG_ON(x) rather than if(x) BUG();
The semantic patch that fixes this problem is as follows:
// <smpl>
@@ identifier x; @@
-if (x) BUG();
+BUG_ON(x);
// </smpl>
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Chris Mason <clm@fb.com>
`struct workspace' used for zlib compression contains two zlib
z_stream-s: `def_strm' used in zlib_compress_pages(), and `inf_strm'
used in zlib_decompress/zlib_decompress_biovec(). None of these
functions use `inf_strm' and `def_strm' simultaniously, meaning that
for every compress/decompress operation we need only one z_stream
(out of two available).
`inf_strm' and `def_strm' are different in size of ->workspace. For
inflate stream we vmalloc() zlib_inflate_workspacesize() bytes, for
deflate stream - zlib_deflate_workspacesize() bytes. On my system zlib
returns the following workspace sizes, correspondingly: 42312 and 268104
(+ guard pages).
Keep only one `z_stream' in `struct workspace' and use it for both
compression and decompression. Hence, instead of vmalloc() of two
z_stream->worskpace-s, allocate only one of size:
max(zlib_deflate_workspacesize(), zlib_inflate_workspacesize())
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
We were returning with 0 (success) because we weren't extracting the
error code from em (PTR_ERR(em)). Fix it.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The tree field of struct extent_state was only used to figure out if
an extent state was connected to an inode's io tree or not. For this
we can just use the rb_node field itself.
On a x86_64 system with this change the sizeof(struct extent_state) is
reduced from 96 bytes down to 88 bytes, meaning that with a page size
of 4096 bytes we can now store 46 extent states per page instead of 42.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
replace IS_ERR/PTR_ERR
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Chris Mason <clm@fb.com>
Marc argued that if there are several btrfs filesystems mounted,
while users even don't know which filesystem hit the corrupted
errors something like generation verification failure.
Since @extent_buffer structure has a member @fs_info, let's output
btrfs device info.
Reported-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we mounted a seed filesystem with degraded option, and then added a new
device into the seed filesystem, then we found adding device failed because
of the IO failure.
Steps to reproduce:
# mkfs.btrfs -d raid1 -m raid1 <dev0> <dev1>
# btrfstune -S 1 <dev0>
# mount <dev0> -o degraded <mnt>
# btrfs device add -f <dev2> <mnt>
It is because the original didn't set the chunk on the seed device to be
read-only if the degraded flag was set. It was introduced by patch f48b90756,
which fixed the problem the raid1 filesystem became read-only after one device
of it was missing. But this fix method was not right, we should set the read-only
flag according to the number of the missing devices, not the degraded mount
option, if the number of the missing devices is less than the max error number
that the profile of the chunk tolerates, we don't set it to be read-only.
Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Btrfs defragment will utilize COW feature, which means this
did not work for nodatacow option, this problem was detected
by xfstests generic/018 with nodatacow mount option.
Fix this problem by forcing cow for a extent with state
@EXTETN_DEFRAG setting.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
as in the disk add patch, disk detached from the volume must be
recorded in the syslog as well for the same reason.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
when we add a new disk to the mounted btrfs we don't record it
as of now, disk add is a critical change of btrfs configuration,
it must be recorded in the syslog to help offline investigations
of customer problems when reported.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Steps to reproduce:
# mkfs.btrfs -f /dev/sdb
# mount /dev/sdb /mnt -o compress-force=lzo
# mount /dev/sdb /mnt -o remount,compress=zlib
# cat /proc/mounts
Remounting from compress-force to compress could not clear compress-force
option. The problem is there is no way for users to clear compress-force
option separately.
Fix this problem by clearing @FORCE_COMPRESS flag when remounting to
compress=xxx.
Suggested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Tested-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The form
(value + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT
is equivalent to
(value + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE
The rest is a simple subsitution, no difference in the generated
assembly code.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The nodesize and leafsize were never of different values. Unify the
usage and make nodesize the one. Cleanup the redundant checks and
helpers.
Shaves a few bytes from .text:
text data bss dec hex filename
852418 24560 23112 900090 dbbfa btrfs.ko.before
851074 24584 23112 898770 db6d2 btrfs.ko.after
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_set_key_type and btrfs_key_type are used inconsistently along with
open coded variants. Other members of btrfs_key are accessed directly
without any helpers anyway.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
There's no user of the return value and we can get rid of the comment in
put_super.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The naming is confusing, generic yet used for a specific cache. Add a
prefix 'ino_' or rename appropriately.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
When a ranged fsync finishes if there are still extent maps in the modified
list, still set the inode's logged_trans and last_log_commit. This is important
in case an inode is fsync'ed and unlinked in the same transaction, to ensure its
inode ref gets deleted from the log and the respective dentries in its parent
are deleted too from the log (if the parent directory was fsync'ed in the same
transaction).
Instead make btrfs_inode_in_log() return false if the list of modified extent
maps isn't empty.
This is an incremental on top of the v4 version of the patch:
"Btrfs: fix fsync data loss after a ranged fsync"
which was added to its v5, but didn't make it on time.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"Filipe is doing a careful pass through fsync problems, and these are
the fixes so far. I'll have one more for rc6 that we're still
testing.
My big commit is fixing up some inode hash races that Al Viro found
(thanks Al)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: use insert_inode_locked4 for inode creation
Btrfs: fix fsync data loss after a ranged fsync
Btrfs: kfree()ing ERR_PTRs
Btrfs: fix crash while doing a ranged fsync
Btrfs: fix corruption after write/fsync failure + fsync + log recovery
Btrfs: fix autodefrag with compression
A bit of churn on the for-linus side that would be nice to have
in the core bits for 3.18, so pull it in to catch us up and make
forward progress easier.
Signed-off-by: Jens Axboe <axboe@fb.com>
Conflicts:
block/scsi_ioctl.c
Btrfs was inserting inodes into the hash table before we had fully
set the inode up on disk. This leaves us open to rare races that allow
two different inodes in memory for the same [root, inode] pair.
This patch fixes things by using insert_inode_locked4 to insert an I_NEW
inode and unlock_new_inode when we're ready for the rest of the kernel
to use the inode.
It also makes sure to init the operations pointers on the inode before
going into the error handling paths.
Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
While we're doing a full fsync (when the inode has the flag
BTRFS_INODE_NEEDS_FULL_SYNC set) that is ranged too (covers only a
portion of the file), we might have ordered operations that are started
before or while we're logging the inode and that fall outside the fsync
range.
Therefore when a full ranged fsync finishes don't remove every extent
map from the list of modified extent maps - as for some of them, that
fall outside our fsync range, their respective ordered operation hasn't
finished yet, meaning the corresponding file extent item wasn't inserted
into the fs/subvol tree yet and therefore we didn't log it, and we must
let the next fast fsync (one that checks only the modified list) see this
extent map and log a matching file extent item to the log btree and wait
for its ordered operation to finish (if it's still ongoing).
A test case for xfstests follows.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The "inherit" in btrfs_ioctl_snap_create_v2() and "vol_args" in
btrfs_ioctl_rm_dev() are ERR_PTRs so we can't call kfree() on them.
These kind of bugs are "One Err Bugs" where there is just one error
label that does everything. I could set the "inherit = NULL" and keep
the single out label but it ends up being more complicated that way. It
makes the code simpler to re-order the unwind so it's in the mirror
order of the allocation and introduce some new error labels.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
bdev_get_queue() returns the request_queue associated with the
specified block_device. blk_get_backing_dev_info() makes use of
bdev_get_queue() to determine the associated bdi given a block_device.
All the callers of bdev_get_queue() including
blk_get_backing_dev_info() assume that bdev_get_queue() may return
NULL and implement NULL handling; however, bdev_get_queue() requires
the passed in block_device is opened and attached to its gendisk.
Because an active gendisk always has a valid request_queue associated
with it, bdev_get_queue() can never return NULL and neither can
blk_get_backing_dev_info().
Make it clear that neither of the two functions can return NULL and
remove NULL handling from all the callers.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Mason <clm@fb.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Percpu allocator now supports allocation mask. Add @gfp to
percpu_counter_init() so that !GFP_KERNEL allocation masks can be used
with percpu_counters too.
We could have left percpu_counter_init() alone and added
percpu_counter_init_gfp(); however, the number of users isn't that
high and introducing _gfp variants to all percpu data structures would
be quite ugly, so let's just do the conversion. This is the one with
the most users. Other percpu data structures are a lot easier to
convert.
This patch doesn't make any functional difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: "David S. Miller" <davem@davemloft.net>
Cc: x86@kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
While doing a ranged fsync, that is, one whose range doesn't cover the
whole possible file range (0 to LLONG_MAX), we can crash under certain
circumstances with a trace like the following:
[41074.641913] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
(...)
[41074.642692] CPU: 0 PID: 24580 Comm: fsx Not tainted 3.16.0-fdm-btrfs-next-45+ #1
(...)
[41074.643886] RIP: 0010:[<ffffffffa01ecc99>] [<ffffffffa01ecc99>] btrfs_ordered_update_i_size+0x279/0x2b0 [btrfs]
(...)
[41074.644919] Stack:
(...)
[41074.644919] Call Trace:
[41074.644919] [<ffffffffa01db531>] btrfs_truncate_inode_items+0x3f1/0xa10 [btrfs]
[41074.644919] [<ffffffffa01eb54f>] ? btrfs_get_logged_extents+0x4f/0x80 [btrfs]
[41074.644919] [<ffffffffa02137a9>] btrfs_log_inode+0x2f9/0x970 [btrfs]
[41074.644919] [<ffffffff81090875>] ? sched_clock_local+0x25/0xa0
[41074.644919] [<ffffffff8164a55e>] ? mutex_unlock+0xe/0x10
[41074.644919] [<ffffffff810af51d>] ? trace_hardirqs_on+0xd/0x10
[41074.644919] [<ffffffffa0214b4f>] btrfs_log_inode_parent+0x1ef/0x560 [btrfs]
[41074.644919] [<ffffffff811d0c55>] ? dget_parent+0x5/0x180
[41074.644919] [<ffffffffa0215d11>] btrfs_log_dentry_safe+0x51/0x80 [btrfs]
[41074.644919] [<ffffffffa01e2d1a>] btrfs_sync_file+0x1ba/0x3e0 [btrfs]
[41074.644919] [<ffffffff811eda6b>] vfs_fsync_range+0x1b/0x30
(...)
The necessary conditions that lead to such crash are:
* an incremental fsync (when the inode doesn't have the
BTRFS_INODE_NEEDS_FULL_SYNC flag set) happened for our file and it logged
a file extent item ending at offset X;
* the file got the flag BTRFS_INODE_NEEDS_FULL_SYNC set in its inode, due
to a file truncate operation that reduces the file to a size smaller
than X;
* a ranged fsync call happens (via an msync for example), with a range that
doesn't cover the whole file and the end of this range, lets call it Y, is
smaller than X;
* btrfs_log_inode, sees the flag BTRFS_INODE_NEEDS_FULL_SYNC set and
calls btrfs_truncate_inode_items() to remove all items from the log
tree that are associated with our file;
* btrfs_truncate_inode_items() removes all of the inode's items, and the lowest
file extent item it removed is the one ending at offset X, where X > 0 and
X > Y - before returning, it calls btrfs_ordered_update_i_size() with an offset
parameter set to X;
* btrfs_ordered_update_i_size() sees that X is greater then the current ordered
size (btrfs_inode's disk_i_size) and then it assumes there can't be any ongoing
ordered operation with a range covering the offset X, calling a BUG_ON() if
such ordered operation exists. This assumption is made because the disk_i_size
is only increased after the corresponding file extent item is added to the
btree (btrfs_finish_ordered_io);
* But because our fsync covers only a limited range, such an ordered extent might
exist, and our fsync callback (btrfs_sync_file) doesn't wait for such ordered
extent to finish when calling btrfs_wait_ordered_range();
And then by the time btrfs_ordered_update_i_size() is called, via:
btrfs_sync_file() ->
btrfs_log_dentry_safe() ->
btrfs_log_inode_parent() ->
btrfs_log_inode() ->
btrfs_truncate_inode_items() ->
btrfs_ordered_update_i_size()
We hit the BUG_ON(), which could never happen if the fsync range covered the whole
possible file range (0 to LLONG_MAX), as we would wait for all ordered extents to
finish before calling btrfs_truncate_inode_items().
So just don't call btrfs_ordered_update_i_size() if we're removing the inode's items
from a log tree, which isn't supposed to change the in memory inode's disk_i_size.
Issue found while running xfstests/generic/127 (happens very rarely for me), more
specifically via the fsx calls that use memory mapped IO (and issue msync calls).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
While writing to a file, in inode.c:cow_file_range() (and same applies to
submit_compressed_extents()), after reserving an extent for the file data,
we create a new extent map for the written range and insert it into the
extent map cache. After that, we create an ordered operation, but if it
fails (due to a transient/temporary-ENOMEM), we return without dropping
that extent map, which points to a reserved extent that is freed when we
return. A subsequent incremental fsync (when the btrfs inode doesn't have
the flag BTRFS_INODE_NEEDS_FULL_SYNC) considers this extent map valid and
logs a file extent item based on that extent map, which points to a disk
extent that doesn't contain valid data - it was freed by us earlier, at this
point it might contain any random/garbage data.
Therefore, if we reach an error condition when cowing a file range after
we added the new extent map to the cache, drop it from the cache before
returning.
Some sequence of steps that lead to this:
$ mkfs.btrfs -f /dev/sdd
$ mount -o commit=9999 /dev/sdd /mnt
$ cd /mnt
$ xfs_io -f -c "pwrite -S 0x01 -b 4096 0 4096" -c "fsync" foo
$ xfs_io -c "pwrite -S 0x02 -b 4096 4096 4096"
$ sync
$ od -t x1 foo
0000000 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01
*
0010000 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02
*
0020000
$ xfs_io -c "pwrite -S 0xa1 -b 4096 0 4096" foo
# Now this write + fsync fail with -ENOMEM, which was returned by
# btrfs_add_ordered_extent() in inode.c:cow_file_range().
$ xfs_io -c "pwrite -S 0xff -b 4096 4096 4096" foo
$ xfs_io -c "fsync" foo
fsync: Cannot allocate memory
# Now do a new write + fsync, which will succeed. Our previous
# -ENOMEM was a transient/temporary error.
$ xfs_io -c "pwrite -S 0xee -b 4096 16384 4096" foo
$ xfs_io -c "fsync" foo
# Our file content (in page cache) is now:
$ od -t x1 foo
0000000 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1
*
0010000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0020000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0040000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
*
0050000
# Now reboot the machine, and mount the fs, so that fsync log replay
# takes place.
# The file content is now weird, in particular the first 8Kb, which
# do not match our data before nor after the sync command above.
$ od -t x1 foo
0000000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
*
0010000 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01
*
0020000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0040000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
*
0050000
# In fact these first 4Kb are a duplicate of the last 4kb block.
# The last write got an extent map/file extent item that points to
# the same disk extent that we got in the write+fsync that failed
# with the -ENOMEM error. btrfs-debug-tree and btrfsck allow us to
# verify that:
$ btrfs-debug-tree /dev/sdd
(...)
item 6 key (257 EXTENT_DATA 0) itemoff 15819 itemsize 53
extent data disk byte 12582912 nr 8192
extent data offset 0 nr 8192 ram 8192
item 7 key (257 EXTENT_DATA 8192) itemoff 15766 itemsize 53
extent data disk byte 0 nr 0
extent data offset 0 nr 8192 ram 8192
item 8 key (257 EXTENT_DATA 16384) itemoff 15713 itemsize 53
extent data disk byte 12582912 nr 4096
extent data offset 0 nr 4096 ram 4096
$ umount /dev/sdd
$ btrfsck /dev/sdd
Checking filesystem on /dev/sdd
UUID: db5e60e1-050d-41e6-8c7f-3d742dea5d8f
checking extents
extent item 12582912 has multiple extent items
ref mismatch on [12582912 4096] extent item 1, found 2
Backref bytes do not match extent backref, bytenr=12582912, ref bytes=4096, backref bytes=8192
backpointer mismatch on [12582912 4096]
Errors found in extent allocation tree or chunk allocation
checking free space cache
checking fs roots
root 5 inode 257 errors 1000, some csum missing
found 131074 bytes used err is 1
total csum bytes: 4
total tree bytes: 131072
total fs tree bytes: 32768
total extent tree bytes: 16384
btree space waste bytes: 123404
file data blocks allocated: 274432
referenced 274432
Btrfs v3.14.1-96-gcc7fd5a-dirty
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"The biggest of these comes from Liu Bo, who tracked down a hang we've
been hitting since moving to kernel workqueues (it's a btrfs bug, not
in the generic code). His patch needs backporting to 3.16 and 3.15
stable, which I'll send once this is in.
Otherwise these are assorted fixes. Most were integrated last week
during KS, but I wanted to give everyone the chance to test the
result, so I waited for rc2 to come out before sending"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (24 commits)
Btrfs: fix task hang under heavy compressed write
Btrfs: fix filemap_flush call in btrfs_file_release
Btrfs: fix crash on endio of reading corrupted block
btrfs: fix leak in qgroup_subtree_accounting() error path
btrfs: Use right extent length when inserting overlap extent map.
Btrfs: clone, don't create invalid hole extent map
Btrfs: don't monopolize a core when evicting inode
Btrfs: fix hole detection during file fsync
Btrfs: ensure tmpfile inode is always persisted with link count of 0
Btrfs: race free update of commit root for ro snapshots
Btrfs: fix regression of btrfs device replace
Btrfs: don't consider the missing device when allocating new chunks
Btrfs: Fix wrong device size when we are resizing the device
Btrfs: don't write any data into a readonly device when scrub
Btrfs: Fix the problem that the replace destroys the seed filesystem
btrfs: Return right extent when fiemap gives unaligned offset and len.
Btrfs: fix wrong extent mapping for DirectIO
Btrfs: fix wrong write range for filemap_fdatawrite_range()
Btrfs: fix wrong missing device counter decrease
Btrfs: fix unzeroed members in fs_devices when creating a fs from seed fs
...
The autodefrag code skips defrag when two extents are adjacent. But one
big advantage for autodefrag is cutting down on the number of small
extents, even when they are adjacent. This commit changes it to defrag
all small extents.
Signed-off-by: Chris Mason <clm@fb.com>
This has been reported and discussed for a long time, and this hang occurs in
both 3.15 and 3.16.
Btrfs now migrates to use kernel workqueue, but it introduces this hang problem.
Btrfs has a kind of work queued as an ordered way, which means that its
ordered_func() must be processed in the way of FIFO, so it usually looks like --
normal_work_helper(arg)
work = container_of(arg, struct btrfs_work, normal_work);
work->func() <---- (we name it work X)
for ordered_work in wq->ordered_list
ordered_work->ordered_func()
ordered_work->ordered_free()
The hang is a rare case, first when we find free space, we get an uncached block
group, then we go to read its free space cache inode for free space information,
so it will
file a readahead request
btrfs_readpages()
for page that is not in page cache
__do_readpage()
submit_extent_page()
btrfs_submit_bio_hook()
btrfs_bio_wq_end_io()
submit_bio()
end_workqueue_bio() <--(ret by the 1st endio)
queue a work(named work Y) for the 2nd
also the real endio()
So the hang occurs when work Y's work_struct and work X's work_struct happens
to share the same address.
A bit more explanation,
A,B,C -- struct btrfs_work
arg -- struct work_struct
kthread:
worker_thread()
pick up a work_struct from @worklist
process_one_work(arg)
worker->current_work = arg; <-- arg is A->normal_work
worker->current_func(arg)
normal_work_helper(arg)
A = container_of(arg, struct btrfs_work, normal_work);
A->func()
A->ordered_func()
A->ordered_free() <-- A gets freed
B->ordered_func()
submit_compressed_extents()
find_free_extent()
load_free_space_inode()
... <-- (the above readhead stack)
end_workqueue_bio()
btrfs_queue_work(work C)
B->ordered_free()
As if work A has a high priority in wq->ordered_list and there are more ordered
works queued after it, such as B->ordered_func(), its memory could have been
freed before normal_work_helper() returns, which means that kernel workqueue
code worker_thread() still has worker->current_work pointer to be work
A->normal_work's, ie. arg's address.
Meanwhile, work C is allocated after work A is freed, work C->normal_work
and work A->normal_work are likely to share the same address(I confirmed this
with ftrace output, so I'm not just guessing, it's rare though).
When another kthread picks up work C->normal_work to process, and finds our
kthread is processing it(see find_worker_executing_work()), it'll think
work C as a collision and skip then, which ends up nobody processing work C.
So the situation is that our kthread is waiting forever on work C.
Besides, there're other cases that can lead to deadlock, but the real problem
is that all btrfs workqueue shares one work->func, -- normal_work_helper,
so this makes each workqueue to have its own helper function, but only a
wraper pf normal_work_helper.
With this patch, I no long hit the above hang.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
We should only be flushing on close if the file was flagged as needing
it during truncate. I broke this with my ordered data vs transaction
commit deadlock fix.
Thanks to Miao Xie for catching this.
Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: Miao Xie <miaox@cn.fujitsu.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
The crash is
------------[ cut here ]------------
kernel BUG at fs/btrfs/extent_io.c:2124!
[...]
Workqueue: btrfs-endio normal_work_helper [btrfs]
RIP: 0010:[<ffffffffa02d6055>] [<ffffffffa02d6055>] end_bio_extent_readpage+0xb45/0xcd0 [btrfs]
This is in fact a regression.
It is because we forgot to increase @offset properly in reading corrupted block,
so that the @offset remains, and this leads to checksum errors while reading
left blocks queued up in the same bio, and then ends up with hiting the above
BUG_ON.
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Coverity pointed this out; in the newly added
qgroup_subtree_accounting(), if btrfs_find_all_roots()
returns an error, we leak at least the parents pointer,
and possibly the roots pointer, depending on what failure
occurs.
If btrfs_find_all_roots() returns an error, we need to
free up all allocations before we return. "roots" is
initialized to NULL, so it should be safe to free
it unconditionally (ulist_free() handles that case).
Cc: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
When current btrfs finds that a new extent map is going to be insereted
but failed with -EEXIST, it will try again to insert the extent map
but with the length of sectorsize.
This is OK if we don't enable 'no-holes' feature since all extent space
is continuous, we will not go into the not found->insert routine.
But if we enable 'no-holes' feature, it will make things out of control.
e.g. in 4K sectorsize, we pass the following args to btrfs_get_extent():
btrfs_get_extent() args: start: 27874 len 4100
28672 27874 28672 27874+4100 32768
|-----------------------|
|---------hole--------------------|---------data----------|
1) not found and insert
Since no extent map containing the range, btrfs_get_extent() will go
into the not_found and insert routine, which will try to insert the
extent map (27874, 27847 + 4100).
2) first overlap
But it overlaps with (28672, 32768) extent, so -EEXIST will be returned
by add_extent_mapping().
3) retry but still overlap
After catching the -EEXIST, then btrfs_get_extent() will try insert it
again but with 4K length, which still overlaps, so -EEXIST will be
returned.
This makes the following patch fail to punch hole.
d77815461f btrfs: Avoid trucating page or punching hole in a already existed hole.
This patch will use the right length, which is the (exsisting->start -
em->start) to insert, making the above patch works in 'no-holes' mode.
Also, some small code style problems in above patch is fixed too.
Reported-by: Filipe David Manana <fdmanana@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Filipe David Manana <fdmanana@suse.com>
Tested-by: Filipe David Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
When cloning a file that consists of an inline extent, we were creating
an extent map that represents a non-existing trailing hole starting at a
file offset that isn't a multiple of the sector size. This happened because
when processing an inline extent we weren't aligning the extent's length to
the sector size, and therefore incorrectly treating the range
[inline_extent_length; sector_size[ as a hole.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
If an inode has a very large number of extent maps, we can spend
a lot of time freeing them, which triggers a soft lockup warning.
Therefore reschedule if we need to when freeing the extent maps
while evicting the inode.
I could trigger this all the time by running xfstests/generic/299 on
a file system with the no-holes feature enabled. That test creates
an inode with 11386677 extent maps.
$ mkfs.btrfs -f -O no-holes $TEST_DEV
$ MKFS_OPTIONS="-O no-holes" ./check generic/299
generic/299 382s ...
Message from syslogd@debian-vm3 at Aug 7 10:44:29 ...
kernel:[85304.208017] BUG: soft lockup - CPU#0 stuck for 22s! [umount:25330]
384s
Ran: generic/299
Passed all 1 tests
$ dmesg
(...)
[86304.300017] BUG: soft lockup - CPU#0 stuck for 23s! [umount:25330]
(...)
[86304.300036] Call Trace:
[86304.300036] [<ffffffff81698ba9>] __slab_free+0x54/0x295
[86304.300036] [<ffffffffa02ee9cc>] ? free_extent_map+0x5c/0xb0 [btrfs]
[86304.300036] [<ffffffff811a6cd2>] kmem_cache_free+0x282/0x2a0
[86304.300036] [<ffffffffa02ee9cc>] free_extent_map+0x5c/0xb0 [btrfs]
[86304.300036] [<ffffffffa02e3775>] btrfs_evict_inode+0xd5/0x660 [btrfs]
[86304.300036] [<ffffffff811e7c8d>] ? __inode_wait_for_writeback+0x6d/0xc0
[86304.300036] [<ffffffff816a389b>] ? _raw_spin_unlock+0x2b/0x40
[86304.300036] [<ffffffff811d8cbb>] evict+0xab/0x180
[86304.300036] [<ffffffff811d8dce>] dispose_list+0x3e/0x60
[86304.300036] [<ffffffff811d9b04>] evict_inodes+0xf4/0x110
[86304.300036] [<ffffffff811bd953>] generic_shutdown_super+0x53/0x110
[86304.300036] [<ffffffff811bdaa6>] kill_anon_super+0x16/0x30
[86304.300036] [<ffffffffa02a78ba>] btrfs_kill_super+0x1a/0xa0 [btrfs]
[86304.300036] [<ffffffff811bd3a9>] deactivate_locked_super+0x59/0x80
[86304.300036] [<ffffffff811be44e>] deactivate_super+0x4e/0x70
[86304.300036] [<ffffffff811dec14>] mntput_no_expire+0x174/0x1f0
[86304.300036] [<ffffffff811deab7>] ? mntput_no_expire+0x17/0x1f0
[86304.300036] [<ffffffff811e0517>] SyS_umount+0x97/0x100
(...)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Tested-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The file hole detection logic during a file fsync wasn't correct,
because it didn't look back (in a previous leaf) for the last file
extent item that can be in a leaf to the left of our leaf and that
has a generation lower than the current transaction id. This made it
assume that a hole exists when it really doesn't exist in the file.
Such false positive hole detection happens in the following scenario:
* We have a file that has many file extent items, covering 3 or more
btree leafs (the first leaf must contain non file extent items too).
* Two ranges of the file are modified, with their extent items being
located at 2 different leafs and those leafs aren't consecutive.
* When processing the second modified leaf, we weren't checking if
some file extent item exists that is located in some leaf that is
between our 2 modified leafs, and therefore assumed the range defined
between the last file extent item in the first leaf and the first file
extent item in the second leaf matched a hole.
Fortunately this didn't result in overriding the log with wrong data,
instead it made the last loop in copy_items() attempt to insert a
duplicated key (for a hole file extent item), which makes the file
fsync code return with -EEXIST to file.c:btrfs_sync_file() which in
turn ends up doing a full transaction commit, which is much more
expensive then writing only to the log tree and wait for it to be
durably persisted (as well as the file's modified extents/pages).
Therefore fix the hole detection logic, so that we don't pay the
cost of doing full transaction commits.
I could trigger this issue with the following test for xfstests (which
never fails, either without or with this patch). The last fsync call
results in a full transaction commit, due to the -EEXIST error mentioned
above. I could also observe this behaviour happening frequently when
running xfstests/generic/075 in a loop.
Test:
_cleanup()
{
_cleanup_flakey
rm -fr $tmp
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
. ./common/dmflakey
# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_dm_flakey
_need_to_be_root
rm -f $seqres.full
# Create a file with many file extent items, each representing a 4Kb extent.
# These items span 3 btree leaves, of 16Kb each (default mkfs.btrfs leaf size
# as of btrfs-progs 3.12).
_scratch_mkfs -l 16384 >/dev/null 2>&1
_init_flakey
SAVE_MOUNT_OPTIONS="$MOUNT_OPTIONS"
MOUNT_OPTIONS="$MOUNT_OPTIONS -o commit=999"
_mount_flakey
# First fsync, inode has BTRFS_INODE_NEEDS_FULL_SYNC flag set.
$XFS_IO_PROG -f -c "pwrite -S 0x01 -b 4096 0 4096" -c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
# For any of the following fsync calls, inode doesn't have the flag
# BTRFS_INODE_NEEDS_FULL_SYNC set.
for ((i = 1; i <= 500; i++)); do
OFFSET=$((4096 * i))
LEN=4096
$XFS_IO_PROG -c "pwrite -S 0x01 $OFFSET $LEN" -c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
done
# Commit transaction and bump next transaction's id (to 7).
sync
# Truncate will set the BTRFS_INODE_NEEDS_FULL_SYNC flag in the btrfs's
# inode runtime flags.
$XFS_IO_PROG -c "truncate 2048000" $SCRATCH_MNT/foo
# Commit transaction and bump next transaction's id (to 8).
sync
# Touch 1 extent item from the first leaf and 1 from the last leaf. The leaf
# in the middle, containing only file extent items, isn't touched. So the
# next fsync, when calling btrfs_search_forward(), won't visit that middle
# leaf. First and 3rd leaf have now a generation with value 8, while the
# middle leaf remains with a generation with value 6.
$XFS_IO_PROG \
-c "pwrite -S 0xee -b 4096 0 4096" \
-c "pwrite -S 0xff -b 4096 2043904 4096" \
-c "fsync" \
$SCRATCH_MNT/foo | _filter_xfs_io
_load_flakey_table $FLAKEY_DROP_WRITES
md5sum $SCRATCH_MNT/foo | _filter_scratch
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
# During mount, we'll replay the log created by the fsync above, and the file's
# md5 digest should be the same we got before the unmount.
_mount_flakey
md5sum $SCRATCH_MNT/foo | _filter_scratch
_unmount_flakey
MOUNT_OPTIONS="$SAVE_MOUNT_OPTIONS"
status=0
exit
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we open a file with O_TMPFILE, don't do any further operation on
it (so that the inode item isn't updated) and then force a transaction
commit, we get a persisted inode item with a link count of 1, and not 0
as it should be.
Steps to reproduce it (requires a modern xfs_io with -T support):
$ mkfs.btrfs -f /dev/sdd
$ mount -o /dev/sdd /mnt
$ xfs_io -T /mnt &
$ sync
Then btrfs-debug-tree shows the inode item with a link count of 1:
$ btrfs-debug-tree /dev/sdd
(...)
fs tree key (FS_TREE ROOT_ITEM 0)
leaf 29556736 items 4 free space 15851 generation 6 owner 5
fs uuid f164d01b-1b92-481d-a4e4-435fb0f843d0
chunk uuid 0e3d0e56-bcca-4a1c-aa5f-cec2c6f4f7a6
item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160
inode generation 3 transid 6 size 0 block group 0 mode 40755 links 1
item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12
inode ref index 0 namelen 2 name: ..
item 2 key (257 INODE_ITEM 0) itemoff 15951 itemsize 160
inode generation 6 transid 6 size 0 block group 0 mode 100600 links 1
item 3 key (ORPHAN ORPHAN_ITEM 257) itemoff 15951 itemsize 0
orphan item
checksum tree key (CSUM_TREE ROOT_ITEM 0)
(...)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
This is a better solution for the problem addressed in the following
commit:
Btrfs: update commit root on snapshot creation after orphan cleanup
(3821f34888)
The previous solution wasn't the best because of 2 reasons:
1) It added another full transaction commit, which is more expensive
than just swapping the commit root with the root;
2) If a reboot happened after the first transaction commit (the one
that creates the snapshot) and before the second transaction commit,
then we would end up with the same problem if a send using that
snapshot was requested before the first transaction commit after
the reboot.
This change addresses those 2 issues. The second issue is addressed by
switching the commit root in the dentry lookup VFS callback, which is
also called by the snapshot/subvol creation ioctl and performs orphan
cleanup if needed. Like the vfs, the ioctl locks the parent inode too,
preventing race issues between a dentry lookup and snapshot creation.
Cc: Alex Lyakas <alex.btrfs@zadarastorage.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit 49c6f736f34f901117c20960ebd7d5e60f12fcac(
btrfs: dev replace should replace the sysfs entry) added the missing sysfs entry
in the process of device replace, but didn't take missing devices into account,
so now we have
BUG: unable to handle kernel NULL pointer dereference at 0000000000000088
IP: [<ffffffffa0268551>] btrfs_kobj_rm_device+0x21/0x40 [btrfs]
...
To reproduce it,
1. mkfs.btrfs -f disk1 disk2
2. mkfs.ext4 disk1
3. mount disk2 /mnt -odegraded
4. btrfs replace start -B 1 disk3 /mnt
--------------------------
This fixes the problem.
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Tested-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The original code allocated new chunks by the number of the writable devices
and missing devices to make sure that any RAID levels on a degraded FS continue
to be honored, but it introduced a problem that it stopped us to allocating
new chunks, the steps to reproduce is following:
# mkfs.btrfs -m raid1 -d raid1 -f <dev0> <dev1>
# mkfs.btrfs -f <dev1> //Removing <dev1> from the original fs
# mount -o degraded <dev0> <mnt>
# dd if=/dev/null of=<mnt>/tmpfile bs=1M
It is because we allocate new chunks only on the writable devices, if we take
the number of missing devices into account, and want to allocate new chunks
with higher RAID level, we will fail becaue we don't have enough writable
device. Fix it by ignoring the number of missing devices when allocating
new chunks.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
total_bytes of device is just a in-memory variant which is used to record
the size of the device, and it might be changed before we resize a device,
if the resize operation fails, it will be fallbacked. But some code used it
to update on-disk metadata of the device, it would cause the problem that
on-disk metadata of the devices was not consistent. We should use the other
variant named disk_total_bytes to update the on-disk metadata of device,
because that variant is updated only when the resize operation is successful.
Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We should not write data into a readonly device especially seed device when
doing scrub, skip those devices.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The seed filesystem was destroyed by the device replace, the reproduce
method is:
# mkfs.btrfs -f <dev0>
# btrfstune -S 1 <dev0>
# mount <dev0> <mnt>
# btrfs device add <dev1> <mnt>
# umount <mnt>
# mount <dev1> <mnt>
# btrfs replace start -f <dev0> <dev2> <mnt>
# umount <mnt>
# mount <dev0> <mnt>
It is because we erase the super block on the seed device. It is wrong,
we should not change anything on the seed device.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
When page aligned start and len passed to extent_fiemap(), the result is
good, but when start and len is not aligned, e.g. start = 1 and len =
4095 is passed to extent_fiemap(), it returns no extent.
The problem is that start and len is all rounded down which causes the
problem. This patch will round down start and round up (start + len) to
return right extent.
Reported-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_next_leaf() will use current leaf's last key to search
and then return a bigger one. So it may still return a file extent
item that is smaller than expected value and we will
get an overflow here for @em->len.
This is easy to reproduce for Btrfs Direct writting, it did not
cause any problem, because writting will re-insert right mapping later.
However, by hacking code to make DIO support compression, wrong extent
mapping is kept and it encounter merging failure(EEXIST) quickly.
Fix this problem by looping to find next file extent item that is bigger
than @start or we could not find anything more.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
filemap_fdatawrite_range() expect the third arg to be @end
not @len, fix it.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The missing devices are accounted by its own fs device, for example
the missing devices in seed filesystem will be accounted by the fs device
of the seed filesystem, not by the new filesystem which is based on
the seed filesystem, so when we remove the missing device in the
seed filesystem, we should decrease the counter of its own fs device.
Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
We forgot to zero some members in fs_devices when we create new fs_devices
from the one of the seed fs. It would cause the problem that we got wrong
chunk profile when allocating chunks. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When FS in unmounted we need to check generation number as well
since devid+uuid combination could match with the missing replaced
disk when it reappears, and without this patch it might pair with
the replaced disk again.
device_list_add() function is called in the following threads,
mount device option
mount argument
ioctl BTRFS_IOC_SCAN_DEV (btrfs dev scan)
ioctl BTRFS_IOC_DEVICES_READY (btrfs dev ready <dev>)
they have been unit tested to work fine with this patch.
If the user knows what he is doing and really want to pair with
replaced disk (which is not a standard operation), then he should
first clear the kernel btrfs device list in the memory by doing
the module unload/load and followed with the mount -o device option.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
device_list_add() is called when user runs btrfs dev scan, which would add
any btrfs device into the btrfs_fs_devices list.
Now think of a mounted btrfs. And a new device which contains the a SB
from the mounted btrfs devices.
In this situation when user runs btrfs dev scan, the current code would
just replace existing device with the new device.
Which is to note that old device is neither closed nor gracefully
removed from the btrfs.
The FS is still operational with the old bdev however the device name
is the btrfs_device is new which is provided by the btrfs dev scan.
reproducer:
devmgt[1] detach /dev/sdc
replace the missing disk /dev/sdc
btrfs rep start -f 1 /dev/sde /btrfs
Label: none uuid: 5dc0aaf4-4683-4050-b2d6-5ebe5f5cd120
Total devices 2 FS bytes used 32.00KiB
devid 1 size 958.94MiB used 115.88MiB path /dev/sde
devid 2 size 958.94MiB used 103.88MiB path /dev/sdd
make /dev/sdc to reappear
devmgt attach host2
btrfs dev scan
btrfs fi show -m
Label: none uuid: 5dc0aaf4-4683-4050-b2d6-5ebe5f5cd120^M
Total devices 2 FS bytes used 32.00KiB^M
devid 1 size 958.94MiB used 115.88MiB path /dev/sdc <- Wrong.
devid 2 size 958.94MiB used 103.88MiB path /dev/sdd
since /dev/sdc has been replaced with /dev/sde, the /dev/sdc shouldn't be
part of the btrfs-fsid when it reappears. If user want it to be part of it
then sys admin should be using btrfs device add instead.
[1] github.com/anajain/devmgt.git
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
For a non-existent key, btrfs_search_slot() sets path->slots[0] to the slot
where the key could have been present, which in this case would be the slot
containing the extent item which would be the next neighbor of the file range
being punched. The current code passes an incremented path->slots[0] and we
skip to the wrong file extent item. This would mean that we would fail to
merge the "yet to be created" hole with the next neighboring hole (if one
exists). Fix this.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The caller of btrfs_submit_direct_hook() will put the original dio bio
when btrfs_submit_direct_hook() return a error number, so we needn't
put the original bio in btrfs_submit_direct_hook().
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs updates from Chris Mason:
"These are all fixes I'd like to get out to a broader audience.
The biggest of the bunch is Mark's quota fix, which is also in the
SUSE kernel, and makes our subvolume quotas dramatically more
accurate.
I've been running xfstests with these against your current git
overnight, but I'm queueing up longer tests as well"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: disable strict file flushes for renames and truncates
Btrfs: fix csum tree corruption, duplicate and outdated checksums
Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch
Btrfs: fix compressed write corruption on enospc
btrfs: correctly handle return from ulist_add
btrfs: qgroup: account shared subtrees during snapshot delete
Btrfs: read lock extent buffer while walking backrefs
Btrfs: __btrfs_mod_ref should always use no_quota
btrfs: adjust statfs calculations according to raid profiles
Truncates and renames are often used to replace old versions of a file
with new versions. Applications often expect this to be an atomic
replacement, even if they haven't done anything to make sure the new
version is fully on disk.
Btrfs has strict flushing in place to make sure that renaming over an
old file with a new file will fully flush out the new file before
allowing the transaction commit with the rename to complete.
This ordering means the commit code needs to be able to lock file pages,
and there are a few paths in the filesystem where we will try to end a
transaction with the page lock held. It's rare, but these things can
deadlock.
This patch removes the ordered flushes and switches to a best effort
filemap_flush like ext4 uses. It's not perfect, but it should fix the
deadlocks.
Signed-off-by: Chris Mason <clm@fb.com>
Under rare circumstances we can end up leaving 2 versions of a checksum
for the same file extent range.
The reason for this is that after calling btrfs_next_leaf we process
slot 0 of the leaf it returns, instead of processing the slot set in
path->slots[0]. Most of the time (by far) path->slots[0] is 0, but after
btrfs_next_leaf() releases the path and before it searches for the next
leaf, another task might cause a split of the next leaf, which migrates
some of its keys to the leaf we were processing before calling
btrfs_next_leaf(). In this case btrfs_next_leaf() returns again the
same leaf but with path->slots[0] having a slot number corresponding
to the first new key it got, that is, a slot number that didn't exist
before calling btrfs_next_leaf(), as the leaf now has more keys than
it had before. So we must really process the returned leaf starting at
path->slots[0] always, as it isn't always 0, and the key at slot 0 can
have an offset much lower than our search offset/bytenr.
For example, consider the following scenario, where we have:
sums->bytenr: 40157184, sums->len: 16384, sums end: 40173568
four 4kb file data blocks with offsets 40157184, 40161280, 40165376, 40169472
Leaf N:
slot = 0 slot = btrfs_header_nritems() - 1
|-------------------------------------------------------------------|
| [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4] |
|-------------------------------------------------------------------|
Leaf N + 1:
slot = 0 slot = btrfs_header_nritems() - 1
|--------------------------------------------------------------------|
| [(CSUM CSUM 40161280), size 32] ... [((CSUM CSUM 40615936), size 8 |
|--------------------------------------------------------------------|
Because we are at the last slot of leaf N, we call btrfs_next_leaf() to
find the next highest key, which releases the current path and then searches
for that next key. However after releasing the path and before finding that
next key, the item at slot 0 of leaf N + 1 gets moved to leaf N, due to a call
to ctree.c:push_leaf_left() (via ctree.c:split_leaf()), and therefore
btrfs_next_leaf() will returns us a path again with leaf N but with the slot
pointing to its new last key (CSUM CSUM 40161280). This new version of leaf N
is then:
slot = 0 slot = btrfs_header_nritems() - 2 slot = btrfs_header_nritems() - 1
|----------------------------------------------------------------------------------------------------|
| [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4] [(CSUM CSUM 40161280), size 32] |
|----------------------------------------------------------------------------------------------------|
And incorrecly using slot 0, makes us set next_offset to 39239680 and we jump
into the "insert:" label, which will set tmp to:
tmp = min((sums->len - total_bytes) >> blocksize_bits,
(next_offset - file_key.offset) >> blocksize_bits) =
min((16384 - 0) >> 12, (39239680 - 40157184) >> 12) =
min(4, (u64)-917504 = 18446744073708634112 >> 12) = 4
and
ins_size = csum_size * tmp = 4 * 4 = 16 bytes.
In other words, we insert a new csum item in the tree with key
(CSUM_OBJECTID CSUM_KEY 40157184 = sums->bytenr) that contains the checksums
for all the data (4 blocks of 4096 bytes each = sums->len). Which is wrong,
because the item with key (CSUM CSUM 40161280) (the one that was moved from
leaf N + 1 to the end of leaf N) contains the old checksums of the last 12288
bytes of our data and won't get those old checksums removed.
So this leaves us 2 different checksums for 3 4kb blocks of data in the tree,
and breaks the logical rule:
Key_N+1.offset >= Key_N.offset + length_of_data_its_checksums_cover
An obvious bad effect of this is that a subsequent csum tree lookup to get
the checksum of any of the blocks with logical offset of 40161280, 40165376
or 40169472 (the last 3 4kb blocks of file data), will get the old checksums.
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We've got bug reports that btrfs crashes when quota is enabled on
32bit kernel, typically with the Oops like below:
BUG: unable to handle kernel NULL pointer dereference at 00000004
IP: [<f9234590>] find_parent_nodes+0x360/0x1380 [btrfs]
*pde = 00000000
Oops: 0000 [#1] SMP
CPU: 0 PID: 151 Comm: kworker/u8:2 Tainted: G S W 3.15.2-1.gd43d97e-default #1
Workqueue: btrfs-qgroup-rescan normal_work_helper [btrfs]
task: f1478130 ti: f147c000 task.ti: f147c000
EIP: 0060:[<f9234590>] EFLAGS: 00010213 CPU: 0
EIP is at find_parent_nodes+0x360/0x1380 [btrfs]
EAX: f147dda8 EBX: f147ddb0 ECX: 00000011 EDX: 00000000
ESI: 00000000 EDI: f147dda4 EBP: f147ddf8 ESP: f147dd38
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 00000004 CR3: 00bf3000 CR4: 00000690
Stack:
00000000 00000000 f147dda4 00000050 00000001 00000000 00000001 00000050
00000001 00000000 d3059000 00000001 00000022 000000a8 00000000 00000000
00000000 000000a1 00000000 00000000 00000001 00000000 00000000 11800000
Call Trace:
[<f923564d>] __btrfs_find_all_roots+0x9d/0xf0 [btrfs]
[<f9237bb1>] btrfs_qgroup_rescan_worker+0x401/0x760 [btrfs]
[<f9206148>] normal_work_helper+0xc8/0x270 [btrfs]
[<c025e38b>] process_one_work+0x11b/0x390
[<c025eea1>] worker_thread+0x101/0x340
[<c026432b>] kthread+0x9b/0xb0
[<c0712a71>] ret_from_kernel_thread+0x21/0x30
[<c0264290>] kthread_create_on_node+0x110/0x110
This indicates a NULL corruption in prefs_delayed list. The further
investigation and bisection pointed that the call of ulist_add_merge()
results in the corruption.
ulist_add_merge() takes u64 as aux and writes a 64bit value into
old_aux. The callers of this function in backref.c, however, pass a
pointer of a pointer to old_aux. That is, the function overwrites
64bit value on 32bit pointer. This caused a NULL in the adjacent
variable, in this case, prefs_delayed.
Here is a quick attempt to band-aid over this: a new function,
ulist_add_merge_ptr() is introduced to pass/store properly a pointer
value instead of u64. There are still ugly void ** cast remaining
in the callers because void ** cannot be taken implicitly. But, it's
safer than explicit cast to u64, anyway.
Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=887046
Cc: <stable@vger.kernel.org> [v3.11+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
When failing to allocate space for the whole compressed extent, we'll
fallback to uncompressed IO, but we've forgotten to redirty the pages
which belong to this compressed extent, and these 'clean' pages will
simply skip 'submit' part and go to endio directly, at last we got data
corruption as we write nothing.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Tested-By: Martin Steigerwald <martin@lichtvoll.de>
Signed-off-by: Chris Mason <clm@fb.com>
ulist_add() can return '1' on sucess, which qgroup_subtree_accounting()
doesn't take into account. As a result, that value can be bubbled up to
callers, causing an error to be printed. Fix this by only returning the
value of ulist_add() when it indicates an error.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
During its tree walk, btrfs_drop_snapshot() will skip any shared
subtrees it encounters. This is incorrect when we have qgroups
turned on as those subtrees need to have their contents
accounted. In particular, the case we're concerned with is when
removing our snapshot root leaves the subtree with only one root
reference.
In those cases we need to find the last remaining root and add
each extent in the subtree to the corresponding qgroup exclusive
counts.
This patch implements the shared subtree walk and a new qgroup
operation, BTRFS_QGROUP_OPER_SUB_SUBTREE. When an operation of
this type is encountered during qgroup accounting, we search for
any root references to that extent and in the case that we find
only one reference left, we go ahead and do the math on it's
exclusive counts.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Before processing the extent buffer, acquire a read lock on it, so
that we're safe against concurrent updates on the extent buffer.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Before I extended the no_quota arg to btrfs_dec/inc_ref because I didn't
understand how snapshot delete was using it and assumed that we needed the
quota operations there. With Mark's work this has turned out to be not the
case, we _always_ need to use no_quota for btrfs_dec/inc_ref, so just drop the
argument and make __btrfs_mod_ref call it's process function with no_quota set
always. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
This has been discussed in thread:
http://thread.gmane.org/gmane.comp.file-systems.btrfs/32528
and this patch implements this proposal:
http://thread.gmane.org/gmane.comp.file-systems.btrfs/32536
Works fine for "clean" raid profiles where the raid factor correction
does the right job. Otherwise it's pessimistic and may show low space
although there's still some left.
The df nubmers are lightly wrong in case of mixed block groups, but this
is not a major usecase and can be addressed later.
The RAID56 numbers are wrong almost the same way as before and will be
addressed separately.
CC: Hugo Mills <hugo@carfax.org.uk>
CC: cwillu <cwillu@cwillu.com>
CC: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Pull vfs updates from Al Viro:
"Stuff in here:
- acct.c fixes and general rework of mnt_pin mechanism. That allows
to go for delayed-mntput stuff, which will permit mntput() on deep
stack without worrying about stack overflows - fs shutdown will
happen on shallow stack. IOW, we can do Eric's umount-on-rmdir
series without introducing tons of stack overflows on new mntput()
call chains it introduces.
- Bruce's d_splice_alias() patches
- more Miklos' rename() stuff.
- a couple of regression fixes (stable fodder, in the end of branch)
and a fix for API idiocy in iov_iter.c.
There definitely will be another pile, maybe even two. I'd like to
get Eric's series in this time, but even if we miss it, it'll go right
in the beginning of for-next in the next cycle - the tricky part of
prereqs is in this pile"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
fix copy_tree() regression
__generic_file_write_iter(): fix handling of sync error after DIO
switch iov_iter_get_pages() to passing maximal number of pages
fs: mark __d_obtain_alias static
dcache: d_splice_alias should detect loops
exportfs: update Exporting documentation
dcache: d_find_alias needn't recheck IS_ROOT && DCACHE_DISCONNECTED
dcache: remove unused d_find_alias parameter
dcache: d_obtain_alias callers don't all want DISCONNECTED
dcache: d_splice_alias should ignore DCACHE_DISCONNECTED
dcache: d_splice_alias mustn't create directory aliases
dcache: close d_move race in d_splice_alias
dcache: move d_splice_alias
namei: trivial fix to vfs_rename_dir comment
VFS: allow ->d_manage() to declare -EISDIR in rcu_walk mode.
cifs: support RENAME_NOREPLACE
hostfs: support rename flags
shmem: support RENAME_EXCHANGE
shmem: support RENAME_NOREPLACE
btrfs: add RENAME_NOREPLACE
...
There are a few d_obtain_alias callers that are using it to get the
root of a filesystem which may already have an alias somewhere else.
This is not the same as the filehandle-lookup case, and none of them
actually need DCACHE_DISCONNECTED set.
It isn't really a serious problem, but it would really be clearer if we
reserved DCACHE_DISCONNECTED for those cases where it's actually needed.
In the btrfs case this was causing a spurious printk from
nfsd/nfsfh.c:fh_verify when it found an unexpected DCACHE_DISCONNECTED
dentry. Josef worked around this by unsetting DCACHE_DISCONNECTED
manually in 3a0dfa6a12 "Btrfs: unset DCACHE_DISCONNECTED when mounting
default subvol", and this replaces that workaround.
Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
RENAME_NOREPLACE is trivial to implement for most filesystems: switch over
to ->rename2() and check for the supported flags. The rest is done by the
VFS.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Chris Mason <clm@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull btrfs fixes from Chris Mason:
"We have two more fixes in my for-linus branch.
I was hoping to also include a fix for a btrfs deadlock with
compression enabled, but we're still nailing that one down"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: test for valid bdev before kobj removal in btrfs_rm_device
Btrfs: fix abnormal long waiting in fsync
commit 99994cd btrfs: dev delete should remove sysfs entry
added a btrfs_kobj_rm_device, which dereferences device->bdev...
right after we check whether device->bdev might be NULL.
I don't honestly know if it's possible to have a NULL device->bdev
here, but assuming that it is (given the test), we need to move
the kobject removal to be under that test.
(Coverity spotted this)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
xfstests generic/127 detected this problem.
With commit 7fc34a62ca, now fsync will only flush
data within the passed range. This is the cause of the above problem,
-- btrfs's fsync has a stage called 'sync log' which will wait for all the
ordered extents it've recorded to finish.
In xfstests/generic/127, with mixed operations such as truncate, fallocate,
punch hole, and mapwrite, we get some pre-allocated extents, and mapwrite will
mmap, and then msync. And I find that msync will wait for quite a long time
(about 20s in my case), thanks to ftrace, it turns out that the previous
fallocate calls 'btrfs_wait_ordered_range()' to flush dirty pages, but as the
range of dirty pages may be larger than 'btrfs_wait_ordered_range()' wants,
there can be some ordered extents created but not getting corresponding pages
flushed, then they're left in memory until we fsync which runs into the
stage 'sync log', and fsync will just wait for the system writeback thread
to flush those pages and get ordered extents finished, so the latency is
inevitable.
This adds a flush similar to btrfs_start_ordered_extent() in
btrfs_wait_logged_extents() to fix that.
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
The current "wait_on_bit" interface requires an 'action'
function to be provided which does the actual waiting.
There are over 20 such functions, many of them identical.
Most cases can be satisfied by one of just two functions, one
which uses io_schedule() and one which just uses schedule().
So:
Rename wait_on_bit and wait_on_bit_lock to
wait_on_bit_action and wait_on_bit_lock_action
to make it explicit that they need an action function.
Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io
which are *not* given an action function but implicitly use
a standard one.
The decision to error-out if a signal is pending is now made
based on the 'mode' argument rather than being encoded in the action
function.
All instances of the old wait_on_bit and wait_on_bit_lock which
can use the new version have been changed accordingly and their
action functions have been discarded.
wait_on_bit{_lock} does not return any specific error code in the
event of a signal so the caller must check for non-zero and
interpolate their own error code as appropriate.
The wait_on_bit() call in __fscache_wait_on_invalidate() was
ambiguous as it specified TASK_UNINTERRUPTIBLE but used
fscache_wait_bit_interruptible as an action function.
David Howells confirms this should be uniformly
"uninterruptible"
The main remaining user of wait_on_bit{,_lock}_action is NFS
which needs to use a freezer-aware schedule() call.
A comment in fs/gfs2/glock.c notes that having multiple 'action'
functions is useful as they display differently in the 'wchan'
field of 'ps'. (and /proc/$PID/wchan).
As the new bit_wait{,_io} functions are tagged "__sched", they
will not show up at all, but something higher in the stack. So
the distinction will still be visible, only with different
function names (gds2_glock_wait versus gfs2_glock_dq_wait in the
gfs2/glock.c case).
Since first version of this patch (against 3.15) two new action
functions appeared, on in NFS and one in CIFS. CIFS also now
uses an action function that makes the same freezer aware
schedule call as NFS.
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: David Howells <dhowells@redhat.com> (fscache, keys)
Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2)
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull btrfs fixes from Chris Mason:
"We've queued up a few fixes in my for-linus branch"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix crash when starting transaction
Btrfs: fix btrfs_print_leaf for skinny metadata
Btrfs: fix race of using total_bytes_pinned
btrfs: use E2BIG instead of EIO if compression does not help
btrfs: remove stale comment from btrfs_flush_all_pending_stuffs
Btrfs: fix use-after-free when cloning a trailing file hole
btrfs: fix null pointer dereference in btrfs_show_devname when name is null
btrfs: fix null pointer dereference in clone_fs_devices when name is null
btrfs: fix nossd and ssd_spread mount option regression
Btrfs: fix race between balance recovery and root deletion
Btrfs: atomically set inode->i_flags in btrfs_update_iflags
btrfs: only unlock block in verify_parent_transid if we locked it
Btrfs: assert send doesn't attempt to start transactions
btrfs compression: reuse recently used workspace
Btrfs: fix crash when mounting raid5 btrfs with missing disks
btrfs: create sprout should rename fsid on the sysfs as well
btrfs: dev replace should replace the sysfs entry
btrfs: dev add should add its sysfs entry
btrfs: dev delete should remove sysfs entry
btrfs: rename add_device_membership to btrfs_kobj_add_device
We wouldn't actuall print the extent information if we had a skinny metadata
item, this fixes that. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
This percpu counter @total_bytes_pinned is introduced to skip unnecessary
operations of 'commit transaction', it accounts for those space we may free
but are stuck in delayed refs.
And we zero out @space_info->total_bytes_pinned every transaction period so
we have a better idea of how much space we'll actually free up by committing
this transaction. However, we do the 'zero out' part a little earlier, before
we actually unpin space, so we end up returning ENOSPC when we actually have
free space that's just unpinned from committing transaction.
xfstests/generic/074 complained then.
This fixes it by actually accounting the percpu pinned number when 'unpin',
and since it's protected by space_info->lock, the race is gone now.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Return codes got updated in 60e1975acb
(btrfs: return errno instead of -1 from compression)
lzo wrapper returns E2BIG in this case, do the same for zlib.
Signed-off-by: David Sterba <dsterba@suse.cz>
The transaction handle was being used after being freed.
Cc: Chris Mason <clm@fb.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
dev->name is null but missing flag is not set.
Strictly speaking the missing flag should have been set, but there
are more places where code just checks if name is null. For now this
patch does the same.
stack:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000064
IP: [<ffffffffa0228908>] btrfs_show_devname+0x58/0xf0 [btrfs]
[<ffffffff81198879>] show_vfsmnt+0x39/0x130
[<ffffffff81178056>] m_show+0x16/0x20
[<ffffffff8117d706>] seq_read+0x296/0x390
[<ffffffff8115aa7d>] vfs_read+0x9d/0x160
[<ffffffff8115b549>] SyS_read+0x49/0x90
[<ffffffff817abe52>] system_call_fastpath+0x16/0x1b
reproducer:
mkfs.btrfs -draid1 -mraid1 /dev/sdg1 /dev/sdg2
btrfstune -S 1 /dev/sdg1
modprobe -r btrfs && modprobe btrfs
mount -o degraded /dev/sdg1 /btrfs
btrfs dev add /dev/sdg3 /btrfs
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
The commit
0780253 btrfs: Cleanup the btrfs_parse_options for remount.
broke ssd options quite badly; it stopped making ssd_spread
imply ssd, and it made "nossd" unsettable.
Put things back at least as well as they were before
(though ssd mount option handling is still pretty odd:
# mount -o "nossd,ssd_spread" works?)
Reported-by: Roman Mamedov <rm@romanrm.net>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
Balance recovery is called when RW mounting or remounting from
RO to RW, it is called to finish roots merging.
When doing balance recovery, relocation root's corresponding
fs root(whose root refs is 0) might be destroyed by cleaner
thread, this will make btrfs fail to mount.
Fix this problem by holding @cleaner_mutex when doing balance
recovery.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This change is based on the corresponding recent change for ext4:
ext4: atomically set inode->i_flags in ext4_set_inode_flags()
That has the following commit message that applies to btrfs as well:
"Use cmpxchg() to atomically set i_flags instead of clearing out the
S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the
EXT4_IMMUTABLE_FL, EXT4_APPEND_FL flags, since this opens up a race
where an immutable file has the immutable flag cleared for a brief
window of time."
Replacing EXT4_IMMUTABLE_FL and EXT4_APPEND_FL with BTRFS_INODE_IMMUTABLE
and BTRFS_INODE_APPEND, respectively.
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
This is a regression from my patch a26e8c9f75, we
need to only unlock the block if we were the one who locked it. Otherwise this
will trip BUG_ON()'s in locking.c Thanks,
cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
When starting a transaction just assert that current->journal_info
doesn't contain a send transaction stub, since send isn't supposed
to start transactions and when it finishes (either successfully or
not) it's supposed to set current->journal_info to NULL.
This is motivated by the change titled:
Btrfs: fix crash when starting transaction
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Add compression `workspace' in free_workspace() to
`idle_workspace' list head, instead of tail. So we have
better chances to reuse most recently used `workspace'.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Creating sprout will change the fsid of the mounted root.
do the same on the sysfs as well.
reproducer:
mount /dev/sdb /btrfs (seed disk)
btrfs dev add /dev/sdc /btrfs
mount -o rw,remount /btrfs
btrfs dev del /dev/sdb /btrfs
mount /dev/sdb /btrfs
Error:
kobject_add_internal failed for fe350492-dc28-4051-a601-e017b17e6145 with -EEXIST, don't try to register things with the same name in the same directory.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
when we replace the device its corresponding sysfs
entry has to be replaced as well
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
we would need the device links to be created,
when device is added.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
when we delete the device from the mounted btrfs,
we would need its corresponding sysfs enty to
be removed as well.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from Chris Mason:
"This fixes some lockups in btrfs reported with rc1. It probably has
some performance impact because it is backing off our spinning locks
more often and switching to a blocking lock. I'll be able to nail
that down next week, but for now I want to get the lockups taken care
of.
Otherwise some more stack reduction and assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix wrong error handle when the device is missing or is not writeable
Btrfs: fix deadlock when mounting a degraded fs
Btrfs: use bio_endio_nodec instead of open code
Btrfs: fix NULL pointer crash when running balance and scrub concurrently
btrfs: Skip scrubbing removed chunks to avoid -ENOENT.
Btrfs: fix broken free space cache after the system crashed
Btrfs: make free space cache write out functions more readable
Btrfs: remove unused wait queue in struct extent_buffer
Btrfs: fix deadlocks with trylock on tree nodes
The original bio might be submitted, so we shoud increase bi_remaining to
account for it when we deal with the error that the device is missing or
is not writeable, or we would skip the endio handle.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The deadlock happened when we mount degraded filesystem, the reproduced
steps are following:
# mkfs.btrfs -f -m raid1 -d raid1 <dev0> <dev1>
# echo 1 > /sys/block/`basename <dev0>`/device/delete
# mount -o degraded <dev1> <mnt>
The reason was that the counter -- bi_remaining was wrong. If the missing
or unwriteable device was the last device in the mapping array, we would
not submit the original bio, so we shouldn't increase bi_remaining of it
in btrfs_end_bio(), or we would skip the final endio handle.
Fix this problem by adding a flag into btrfs bio structure. If we submit
the original bio, we will set the flag, and we increase bi_remaining counter,
or we don't.
Though there is another way to fix it -- decrease bi_remaining counter of the
original bio when we make sure the original bio is not submitted, this method
need add more check and is easy to make mistake.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
While running balance, scrub, fsstress concurrently we hit the
following kernel crash:
[56561.448845] BTRFS info (device sde): relocating block group 11005853696 flags 132
[56561.524077] BUG: unable to handle kernel NULL pointer dereference at 0000000000000078
[56561.524237] IP: [<ffffffffa038956d>] scrub_chunk.isra.12+0xdd/0x130 [btrfs]
[56561.524297] PGD 9be28067 PUD 7f3dd067 PMD 0
[56561.524325] Oops: 0000 [#1] SMP
[....]
[56561.527237] Call Trace:
[56561.527309] [<ffffffffa038980e>] scrub_enumerate_chunks+0x24e/0x490 [btrfs]
[56561.527392] [<ffffffff810abe00>] ? abort_exclusive_wait+0x50/0xb0
[56561.527476] [<ffffffffa038add4>] btrfs_scrub_dev+0x1a4/0x530 [btrfs]
[56561.527561] [<ffffffffa0368107>] btrfs_ioctl+0x13f7/0x2a90 [btrfs]
[56561.527639] [<ffffffff811c82f0>] do_vfs_ioctl+0x2e0/0x4c0
[56561.527712] [<ffffffff8109c384>] ? vtime_account_user+0x54/0x60
[56561.527788] [<ffffffff810f768c>] ? __audit_syscall_entry+0x9c/0xf0
[56561.527870] [<ffffffff811c8551>] SyS_ioctl+0x81/0xa0
[56561.527941] [<ffffffff815707f7>] tracesys+0xdd/0xe2
[...]
[56561.528304] RIP [<ffffffffa038956d>] scrub_chunk.isra.12+0xdd/0x130 [btrfs]
[56561.528395] RSP <ffff88004c0f5be8>
[56561.528454] CR2: 0000000000000078
This is because in btrfs_relocate_chunk(), we will free @bdev directly while
scrub may still hold extent mapping, and may access freed memory.
Fix this problem by wrapping freeing @bdev work into free_extent_map() which
is based on reference count.
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When run scrub with balance, sometimes -ENOENT will be returned, since
in scrub_enumerate_chunks() will search dev_extent in *COMMIT_ROOT*, but
btrfs_lookup_block_group() will search block group in *MEMORY*, so if a
chunk is removed but not committed, -ENOENT will be returned.
However, there is no need to stop scrubbing since other chunks may be
scrubbed without problem.
So this patch changes the behavior to skip removed chunks and continue
to scrub the rest.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we mounted the filesystem after the crash, we got the following
message:
BTRFS error (device xxx): block group xxxx has wrong amount of free space
BTRFS error (device xxx): failed to load free space cache for block group xxx
It is because we didn't update the metadata of the allocated space (in extent
tree) until the file data was written into the disk. During this time, there was
no information about the allocated spaces in either the extent tree nor the
free space cache. when we wrote out the free space cache at this time (commit
transaction), those spaces were lost. In fact, only the free space that is
used to store the file data had this problem, the others didn't because
the metadata of them is updated in the same transaction context.
There are many methods which can fix the above problem
- track the allocated space, and write it out when we write out the free
space cache
- account the size of the allocated space that is used to store the file
data, if the size is not zero, don't write out the free space cache.
The first one is complex and may make the performance drop down.
This patch chose the second method, we use a per-block-group variant to
account the size of that allocated space. Besides that, we also introduce
a per-block-group read-write semaphore to avoid the race between
the allocation and the free space cache write out.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This patch makes the free space cache write out functions more readable,
and beisdes that, it also reduces the stack space that the function --
__btrfs_write_out_cache uses from 194bytes to 144bytes.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
The lock_wq wait queue is not used anywhere, therefore just remove it.
On a x86_64 system, this reduced sizeof(struct extent_buffer) from 320
bytes down to 296 bytes, which means a 4Kb page can now be used for
13 extent buffers instead of 12.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
The Btrfs tree trylock function is poorly named. It always takes
the spinlock and backs off if the blocking lock is held. This
can lead to surprising lockups because people expect it to really be a
trylock.
This commit makes it a pure trylock, both for the spinlock and the
blocking lock. It also reworks the nested lock handling slightly to
avoid taking the read lock while a spinning write lock might be held.
Signed-off-by: Chris Mason <clm@fb.com>
Pull more btrfs updates from Chris Mason:
"This has a few fixes since our last pull and a new ioctl for doing
btree searches from userland. It's very similar to the existing
ioctl, but lets us return larger items back down to the app"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix error handling in create_pending_snapshot
btrfs: fix use of uninit "ret" in end_extent_writepage()
btrfs: free ulist in qgroup_shared_accounting() error path
Btrfs: fix qgroups sanity test crash or hang
btrfs: prevent RCU warning when dereferencing radix tree slot
Btrfs: fix unfinished readahead thread for raid5/6 degraded mounting
btrfs: new ioctl TREE_SEARCH_V2
btrfs: tree_search, search_ioctl: direct copy to userspace
btrfs: new function read_extent_buffer_to_user
btrfs: tree_search, copy_to_sk: return needed size on EOVERFLOW
btrfs: tree_search, copy_to_sk: return EOVERFLOW for too small buffer
btrfs: tree_search, search_ioctl: accept varying buffer
btrfs: tree_search: eliminate redundant nr_items check
fcebe456 cut and pasted some code to a later point
in create_pending_snapshot(), but didn't switch
to the appropriate error handling for this stage
of the function.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
If this condition in end_extent_writepage() is false:
if (tree->ops && tree->ops->writepage_end_io_hook)
we will then test an uninitialized "ret" at:
ret = ret < 0 ? ret : -EIO;
The test for ret is for the case where ->writepage_end_io_hook
failed, and we'd choose that ret as the error; but if
there is no ->writepage_end_io_hook, nothing sets ret.
Initializing ret to 0 should be sufficient; if
writepage_end_io_hook wasn't set, (!uptodate) means
non-zero err was passed in, so we choose -EIO in that case.
Signed-of-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
If tmp = ulist_alloc(GFP_NOFS) fails, we return without
freeing the previously allocated qgroups = ulist_alloc(GFP_NOFS)
and cause a memory leak.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
Mark the dereference as protected by lock. Not doing so triggers
an RCU warning since the radix tree assumed that RCU is in use.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Steps to reproduce:
# mkfs.btrfs -f /dev/sd[b-f] -m raid5 -d raid5
# mkfs.ext4 /dev/sdc --->corrupt one of btrfs device
# mount /dev/sdb /mnt -o degraded
# btrfs scrub start -BRd /mnt
This is because readahead would skip missing device, this is not true
for RAID5/6, because REQ_GET_READ_MIRRORS return 1 for RAID5/6 block
mapping. If expected data locates in missing device, readahead thread
would not call __readahead_hook() which makes event @rc->elems=0
wait forever.
Fix this problem by checking return value of btrfs_map_block(),we
can only skip missing device safely if there are several mirrors.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This new ioctl call allows the user to supply a buffer of varying size in which
a tree search can store its results. This is much more flexible if you want to
receive items which are larger than the current fixed buffer of 3992 bytes or
if you want to fetch more items at once. Items larger than this buffer are for
example some of the type EXTENT_CSUM.
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
By copying each found item seperatly to userspace, we do not need extra
buffer in the kernel.
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
This new function reads the content of an extent directly to user memory.
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
If an item in tree_search is too large to be stored in the given buffer, return
the needed size (including the header).
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
In copy_to_sk, if an item is too large for the given buffer, it now returns
-EOVERFLOW instead of copying a search_header with len = 0. For backward
compatibility for the first item it still copies such a header to the buffer,
but not any other following items, which could have fitted.
tree_search changes -EOVERFLOW back to 0 to behave similiar to the way it
behaved before this patch.
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
rewrite search_ioctl to accept a buffer with varying size
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
If the amount of items reached the given limit of nr_items, we can leave
copy_to_sk without updating the key. Also by returning 1 we leave the loop in
search_ioctl without rechecking if we reached the given limit.
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
Pull vfs updates from Al Viro:
"This the bunch that sat in -next + lock_parent() fix. This is the
minimal set; there's more pending stuff.
In particular, I really hope to get acct.c fixes merged this cycle -
we need that to deal sanely with delayed-mntput stuff. In the next
pile, hopefully - that series is fairly short and localized
(kernel/acct.c, fs/super.c and fs/namespace.c). In this pile: more
iov_iter work. Most of prereqs for ->splice_write with sane locking
order are there and Kent's dio rewrite would also fit nicely on top of
this pile"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
lock_parent: don't step on stale ->d_parent of all-but-freed one
kill generic_file_splice_write()
ceph: switch to iter_file_splice_write()
shmem: switch to iter_file_splice_write()
nfs: switch to iter_splice_write_file()
fs/splice.c: remove unneeded exports
ocfs2: switch to iter_file_splice_write()
->splice_write() via ->write_iter()
bio_vec-backed iov_iter
optimize copy_page_{to,from}_iter()
bury generic_file_aio_{read,write}
lustre: get rid of messing with iovecs
ceph: switch to ->write_iter()
ceph_sync_direct_write: stop poking into iov_iter guts
ceph_sync_read: stop poking into iov_iter guts
new helper: copy_page_from_iter()
fuse: switch to ->write_iter()
btrfs: switch to ->write_iter()
ocfs2: switch to ->write_iter()
xfs: switch to ->write_iter()
...
Pull btrfs updates from Chris Mason:
"The biggest change here is Josef's rework of the btrfs quota
accounting, which improves the in-memory tracking of delayed extent
operations.
I had been working on Btrfs stack usage for a while, mostly because it
had become impossible to do long stress runs with slab, lockdep and
pagealloc debugging turned on without blowing the stack. Even though
you upgraded us to a nice king sized stack, I kept most of the
patches.
We also have some very hard to find corruption fixes, an awesome sysfs
use after free, and the usual assortment of optimizations, cleanups
and other fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (80 commits)
Btrfs: convert smp_mb__{before,after}_clear_bit
Btrfs: fix scrub_print_warning to handle skinny metadata extents
Btrfs: make fsync work after cloning into a file
Btrfs: use right type to get real comparison
Btrfs: don't check nodes for extent items
Btrfs: don't release invalid page in btrfs_page_exists_in_range()
Btrfs: make sure we retry if page is a retriable exception
Btrfs: make sure we retry if we couldn't get the page
btrfs: replace EINVAL with EOPNOTSUPP for dev_replace raid56
trivial: fs/btrfs/ioctl.c: fix typo s/substract/subtract/
Btrfs: fix leaf corruption after __btrfs_drop_extents
Btrfs: ensure btrfs_prev_leaf doesn't miss 1 item
Btrfs: fix clone to deal with holes when NO_HOLES feature is enabled
btrfs: free delayed node outside of root->inode_lock
btrfs: replace EINVAL with ERANGE for resize when ULLONG_MAX
Btrfs: fix transaction leak during fsync call
btrfs: Avoid trucating page or punching hole in a already existed hole.
Btrfs: update commit root on snapshot creation after orphan cleanup
Btrfs: ioctl, don't re-lock extent range when not necessary
Btrfs: avoid visiting all extent items when cloning a range
...
The skinny extents are intepreted incorrectly in scrub_print_warning(),
and end up hitting the BUG() in btrfs_extent_inline_ref_size.
Reported-by: Konstantinos Skarlatos <k.skarlatos@gmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
When cloning into a file, we were correctly replacing the extent
items in the target range and removing the extent maps. However
we weren't replacing the extent maps with new ones that point to
the new extents - as a consequence, an incremental fsync (when the
inode doesn't have the full sync flag) was a NOOP, since it relies
on the existence of extent maps in the modified list of the inode's
extent map tree, which was empty. Therefore add new extent maps to
reflect the target clone range.
A test case for xfstests follows.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
We want to make sure the point is still within the extent item, not to verify
the memory it's pointing to.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
The backref code was looking at nodes as well as leaves when we tried to
populate extent item entries. This is not good, and although we go away with it
for the most part because we'd skip where disk_bytenr != random_memory,
sometimes random_memory would match and suddenly boom. This fixes that problem.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
In inode.c:btrfs_page_exists_in_range(), if the page we got from
the radix tree is an exception entry, which can't be retried, we
exit the loop with a non-NULL page and then call page_cache_release
against it, which is not ok since it's not a valid page. This could
also make us return true when we shouldn't.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
In inode.c:btrfs_page_exists_in_range(), if the page we get from the
radix tree is an exception which should make us retry, set page to
NULL in order to really retry, because otherwise we don't get another
loop iteration executed (page != NULL makes the while loop exit).
This also was making us call page_cache_release after exiting the loop,
which isn't correct because page doesn't point to a valid page, and
possibly return true from the function when we shouldn't.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
In inode.c:btrfs_page_exists_in_range(), if we can't get the page
we need to retry. However we weren't retrying because we weren't
setting page to NULL, which makes the while loop exit immediately
and will make us call page_cache_release after exiting the loop
which is incorrect because our page get didn't succeed. This could
also make us return true when we shouldn't.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
To return EOPNOTSUPP is more user friendly than to return EINVAL,
and then user-space tool will show that the dev_replace operation
for raid56 is not currently supported rather than showing that
there is an invalid argument.
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Chris Mason <clm@fb.com>
Several reports about leaf corruption has been floating on the list, one of them
points to __btrfs_drop_extents(), and we find that the leaf becomes corrupted
after __btrfs_drop_extents(), it's really a rare case but it does exist.
The problem turns out to be btrfs_next_leaf() called in __btrfs_drop_extents().
So in btrfs_next_leaf(), we release the current path to re-search the last key of
the leaf for locating next leaf, and we've taken it into account that there might
be balance operations between leafs during this 'unlock and re-lock' dance, so
we check the path again and advance it if there are now more items available.
But things are a bit different if that last key happens to be removed and balance
gets a bigger key as the last one, and btrfs_search_slot will return it with
ret > 0, IOW, nothing change in this leaf except the new last key, then we think
we're okay because there is no more item balanced in, fine, we thinks we can
go to the next leaf.
However, we should return that bigger key, otherwise we deserve leaf corruption,
for example, in endio, skipping that key means that __btrfs_drop_extents() thinks
it has dropped all extent matched the required range and finish_ordered_io can
safely insert a new extent, but it actually doesn't and ends up a leaf
corruption.
One may be asking that why our locking on extent io tree doesn't work as
expected, ie. it should avoid this kind of race situation. But in
__btrfs_drop_extents(), we don't always find extents which are included within
our locking range, IOW, extents can start before our searching start, in this
case locking on extent io tree doesn't protect us from the race.
This takes the special case into account.
Reviewed-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
We might have had an item with the previous key in the tree right
before we released our path. And after we released our path, that
item might have been pushed to the first slot (0) of the leaf we
were holding due to a tree balance. Alternatively, an item with the
previous key can exist as the only element of a leaf (big fat item).
Therefore account for these 2 cases, so that our callers (like
btrfs_previous_item) don't miss an existing item with a key matching
the previous key we computed above.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
If the NO_HOLES feature is enabled holes don't have file extent items in
the btree that represent them anymore. This made the clone operation
ignore the gaps that exist between consecutive file extent items and
therefore not create the holes at the destination. When not using the
NO_HOLES feature, the holes were created at the destination.
A test case for xfstests follows.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
On heavy workloads, we're seeing soft lockup warnings on
root->inode_lock in __btrfs_release_delayed_node. The low hanging fruit
is to reduce the size of the critical section.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
To be accurate about the error case,
if the new size is beyond ULLONG_MAX, return ERANGE instead of EINVAL.
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
If btrfs_log_dentry_safe() returns an error, we set ret to 1 and
fall through with the goal of committing the transaction. However,
in the case where the inode doesn't need a full sync, we would call
btrfs_wait_ordered_range() against the target range for our inode,
and if it returned an error, we would return without commiting or
ending the transaction.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_punch_hole() will truncate unaligned pages or punch hole on a
already existed hole.
This will cause unneeded zero page or holes splitting the original huge
hole.
This patch will skip already existed holes before any page truncating or
hole punching.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
On snapshot creation (either writable or read-only), we do orphan cleanup
against the root of the snapshot. If the cleanup did remove any orphans,
then the current root node will be different from the commit root node
until the next transaction commit happens.
A send operation always uses the commit root of a snapshot - this means
it will see the orphans if it starts computing the send stream before the
next transaction commit happens (triggered by a timer or sync() for .e.g),
which is when the commit root gets assigned a reference to current root,
where the orphans are not visible anymore. The consequence of send seeing
the orphans is explained below.
For example:
mkfs.btrfs -f /dev/sdd
mount -o commit=999 /dev/sdd /mnt
# open a file with O_TMPFILE and leave it open
# write some data to the file
btrfs subvolume snapshot -r /mnt /mnt/snap1
btrfs send /mnt/snap1 -f /tmp/send.data
The send operation will fail with the following error:
ERROR: send ioctl failed with -116: Stale file handle
What happens here is that our snapshot has an orphan inode still visible
through the commit root, that corresponds to the tmpfile. However send
will attempt to call inode.c:btrfs_iget(), with the goal of reading the
file's data, which will return -ESTALE because it will use the current
root (and not the commit root) of the snapshot.
Of course, there are other cases where we can get orphans, but this
example using a tmpfile makes it much easier to reproduce the issue.
Therefore on snapshot creation, after calling btrfs_orphan_cleanup, if
the commit root is different from the current root, just commit the
transaction associated with the snapshot's root (if it exists), so that
a send will not see any orphans that don't exist anymore. This also
guarantees a send will always see the same content regardless of whether
a transaction commit happened already before the send was requested and
after the orphan cleanup (meaning the commit root and current roots are
the same) or it hasn't happened yet (commit and current roots are
different).
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
In ioctl.c:lock_extent_range(), after locking our target range, the
ordered extent that btrfs_lookup_first_ordered_extent() returns us
may not overlap our target range at all. In this case we would just
unlock our target range, wait for any new ordered extents that overlap
the range to complete, lock again the range and repeat all these steps
until we don't get any ordered extent and the delalloc flag isn't set
in the io tree for our target range.
Therefore just stop if we get an ordered extent that doesn't overlap
our target range and the dealalloc flag isn't set for the range in
the inode's io tree.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
When cloning a range of a file, we were visiting all the extent items in
the btree that belong to our source inode. We don't need to visit those
extent items that don't overlap the range we are cloning, as doing so only
makes us waste time and do unnecessary btree navigations (btrfs_next_leaf)
for inodes that have a large number of file extent items in the btree.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
We were setting the BTRFS_ROOT_SUBVOL_DEAD flag on the root of the
parent of our target snapshot, instead of setting it in the target
snapshot's root.
This is easy to observe by running the following scenario:
mkfs.btrfs -f /dev/sdd
mount /dev/sdd /mnt
btrfs subvolume create /mnt/first_subvol
btrfs subvolume snapshot -r /mnt /mnt/mysnap1
btrfs subvolume delete /mnt/first_subvol
btrfs subvolume snapshot -r /mnt /mnt/mysnap2
btrfs send -p /mnt/mysnap1 /mnt/mysnap2 -f /tmp/send.data
The send command failed because the send ioctl returned -EPERM.
A test case for xfstests follows.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
We were cleaning the clone target file range from the page cache before
we did replace the file extent items in the fs tree. This was racy,
as right after cleaning the relevant range from the page cache and before
replacing the file extent items, a read against that range could be
performed by another task and populate again the page cache with stale
data (stale after the cloning finishes). This would result in reads after
the clone operation successfully finishes to get old data (and potentially
for a very long time). Therefore evict the pages after replacing the file
extent items, so that subsequent reads will always get the new data.
Similarly, we were prone to races while cloning the file extent items
because we weren't locking the target range and wait for any existing
ordered extents against that range to complete. It was possible that
after cloning the extent items, a write operation that was performed
before the clone operation and overlaps the same range, would end up
undoing all or part of the work the clone operation did (a worker task
running inode.c:btrfs_finish_ordered_io). Therefore lock the target
range in the io tree, wait for all pending ordered extents against that
range to finish and then safely perform the cloning.
The issue of reading stale data after the clone operation is easy to
reproduce by running the following C program in a loop until it exits
with return value 1.
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <pthread.h>
#include <fcntl.h>
#include <assert.h>
#include <asm/types.h>
#include <linux/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#define SRC_FILE "/mnt/sdd/foo"
#define DST_FILE "/mnt/sdd/bar"
#define FILE_SIZE (16 * 1024)
#define PATTERN_SRC 'X'
#define PATTERN_DST 'Y'
struct btrfs_ioctl_clone_range_args {
__s64 src_fd;
__u64 src_offset, src_length;
__u64 dest_offset;
};
#define BTRFS_IOCTL_MAGIC 0x94
#define BTRFS_IOC_CLONE_RANGE _IOW(BTRFS_IOCTL_MAGIC, 13, \
struct btrfs_ioctl_clone_range_args)
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
static int clone_done = 0;
static int reader_ready = 0;
static int stale_data = 0;
static void *reader_loop(void *arg)
{
char buf[4096], want_buf[4096];
memset(want_buf, PATTERN_SRC, 4096);
pthread_mutex_lock(&mutex);
reader_ready = 1;
pthread_mutex_unlock(&mutex);
while (1) {
int done, fd, ret;
fd = open(DST_FILE, O_RDONLY);
assert(fd != -1);
pthread_mutex_lock(&mutex);
done = clone_done;
pthread_mutex_unlock(&mutex);
ret = read(fd, buf, 4096);
assert(ret == 4096);
close(fd);
if (done) {
ret = memcmp(buf, want_buf, 4096);
if (ret == 0) {
printf("Found new content\n");
} else {
printf("Found old content\n");
pthread_mutex_lock(&mutex);
stale_data = 1;
pthread_mutex_unlock(&mutex);
}
break;
}
}
return NULL;
}
int main(int argc, char *argv[])
{
pthread_t reader;
int ret, i, fd;
struct btrfs_ioctl_clone_range_args clone_args;
int fd1, fd2;
ret = remove(SRC_FILE);
if (ret == -1 && errno != ENOENT) {
fprintf(stderr, "Error deleting src file: %s\n", strerror(errno));
return 1;
}
ret = remove(DST_FILE);
if (ret == -1 && errno != ENOENT) {
fprintf(stderr, "Error deleting dst file: %s\n", strerror(errno));
return 1;
}
fd = open(SRC_FILE, O_CREAT | O_WRONLY | O_TRUNC, S_IRWXU);
assert(fd != -1);
for (i = 0; i < FILE_SIZE; i++) {
char c = PATTERN_SRC;
ret = write(fd, &c, 1);
assert(ret == 1);
}
close(fd);
fd = open(DST_FILE, O_CREAT | O_WRONLY | O_TRUNC, S_IRWXU);
assert(fd != -1);
for (i = 0; i < FILE_SIZE; i++) {
char c = PATTERN_DST;
ret = write(fd, &c, 1);
assert(ret == 1);
}
close(fd);
sync();
ret = pthread_create(&reader, NULL, reader_loop, NULL);
assert(ret == 0);
while (1) {
int r;
pthread_mutex_lock(&mutex);
r = reader_ready;
pthread_mutex_unlock(&mutex);
if (r) break;
}
fd1 = open(SRC_FILE, O_RDONLY);
if (fd1 < 0) {
fprintf(stderr, "Error open src file: %s\n", strerror(errno));
return 1;
}
fd2 = open(DST_FILE, O_RDWR);
if (fd2 < 0) {
fprintf(stderr, "Error open dst file: %s\n", strerror(errno));
return 1;
}
clone_args.src_fd = fd1;
clone_args.src_offset = 0;
clone_args.src_length = 4096;
clone_args.dest_offset = 0;
ret = ioctl(fd2, BTRFS_IOC_CLONE_RANGE, &clone_args);
assert(ret == 0);
close(fd1);
close(fd2);
pthread_mutex_lock(&mutex);
clone_done = 1;
pthread_mutex_unlock(&mutex);
ret = pthread_join(reader, NULL);
assert(ret == 0);
pthread_mutex_lock(&mutex);
ret = stale_data ? 1 : 0;
pthread_mutex_unlock(&mutex);
return ret;
}
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
There is otherwise a risk of a possible null pointer dereference.
Was largely found by using a static code analysis program called cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Chris Mason <clm@fb.com>
We are currently allocating space_info objects in an array when we
allocate space_info. When a user does something like:
# btrfs balance start -mconvert=raid1 -dconvert=raid1 /mnt
# btrfs balance start -mconvert=single -dconvert=single /mnt -f
# btrfs balance start -mconvert=raid1 -dconvert=raid1 /
We can end up with memory corruption since the kobject hasn't
been reinitialized properly and the name pointer was left set.
The rationale behind allocating them statically was to avoid
creating a separate kobject container that just contained the
raid type. It used the index in the array to determine the index.
Ultimately, though, this wastes more memory than it saves in all
but the most complex scenarios and introduces kobject lifetime
questions.
This patch allocates the kobjects dynamically instead. Note that
we also remove the kobject_get/put of the parent kobject since
kobject_add and kobject_del do that internally.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
We were limiting the sum of the xattr name and value lengths to PATH_MAX,
which is not correct, specially on filesystems created with btrfs-progs
v3.12 or higher, where the default leaf size is max(16384, PAGE_SIZE), or
systems with page sizes larger than 4096 bytes.
Xattrs have their own specific maximum name and value lengths, which depend
on the leaf size, therefore use these limits to be able to send xattrs with
sizes larger than PATH_MAX.
A test case for xfstests follows.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
If we are doing an incremental send and the base snapshot has a
directory with name X that doesn't exist anymore in the second
snapshot and a new subvolume/snapshot exists in the second snapshot
that has the same name as the directory (name X), the incremental
send would fail with -ENOENT error. This is because it attempts
to lookup for an inode with a number matching the objectid of a
root, which doesn't exist.
Steps to reproduce:
mkfs.btrfs -f /dev/sdd
mount /dev/sdd /mnt
mkdir /mnt/testdir
btrfs subvolume snapshot -r /mnt /mnt/mysnap1
rmdir /mnt/testdir
btrfs subvolume create /mnt/testdir
btrfs subvolume snapshot -r /mnt /mnt/mysnap2
btrfs send -p /mnt/mysnap1 /mnt/mysnap2 -f /tmp/send.data
A test case for xfstests follows.
Reported-by: Robert White <rwhite@pobox.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Delayed extent operations are triggered during transaction commits.
The goal is to queue up a healthly batch of changes to the extent
allocation tree and run through them in bulk.
This farms them off to async helper threads. The goal is to have the
bulk of the delayed operations being done in the background, but this is
also important to limit our stack footprint.
Signed-off-by: Chris Mason <clm@fb.com>
__extent_writepage has two unrelated parts. First it does the delayed
allocation dance and second it does the mapping and IO for the page
we're actually writing.
This splits it up into those two parts so the stack from one doesn't
impact the stack from the other.
Signed-off-by: Chris Mason <clm@fb.com>
In these instances, we are trying to determine if a page has been accessed
since we began the operation for the sake of retry. This is easily
accomplished by doing a gang lookup in the page mapping radix tree, and it
saves us the dependency on the flag (so that we might eventually delete
it).
btrfs_page_exists_in_range borrows heavily from find_get_page, replacing
the radix tree look up with a gang lookup of 1, so that we can find the
next highest page >= index and see if it falls into our lock range.
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Alex Gartrell <agartrell@fb.com>
This adds noinline_for_stack to two helpers used by
btree_write_cache_pages. It shaves us down from 424 bytes on the
stack to 280.
Signed-off-by: Chris Mason <clm@fb.com>
__btrfs_write_out_cache was one of our stack pigs. This breaks it
up into helper functions and slims it down to 194 bytes.
Signed-off-by: Chris Mason <clm@fb.com>
I have an opinion that system logs /var/log/messages are
valuable info to investigate the real system issues at
the data center. People handling data center issues
do spend a lot time and efforts analyzing messages
files. Having usage error logged into /var/log/messages
is something we should avoid.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
I've noticed an extra line after "use no compression", but search
revealed much more in messages of more critical levels and rare errors.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
We need to NULL the cached_state after freeing it, otherwise
we might free it again if find_delalloc_range doesn't find anything.
Signed-off-by: Chris Mason <clm@fb.com>
cc: stable@vger.kernel.org
use the newer and more pleasant kstrtoull() to replace simple_strtoull(),
because simple_strtoull() is marked for obsoletion.
Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>
Seeding device support allows us to create a new filesystem
based on existed filesystem.
However newly created filesystem's @total_devices should include seed
devices. This patch fix the following problem:
# mkfs.btrfs -f /dev/sdb
# btrfstune -S 1 /dev/sdb
# mount /dev/sdb /mnt
# btrfs device add -f /dev/sdc /mnt --->fs_devices->total_devices = 1
# umount /mnt
# mount /dev/sdc /mnt --->fs_devices->total_devices = 2
This is because we record right @total_devices in superblock, but
@fs_devices->total_devices is reset to be 0 in btrfs_prepare_sprout().
Fix this problem by not resetting @fs_devices->total_devices.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Even CONFIG_BTRFS_FS_POSIX_ACL is not defined, the acl still could
been enabled using a mount option, and now fs/btrfs/acl.o is not
built, so the mount options will appear to be supported but will
be silently ignored.
Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
This exercises the various parts of the new qgroup accounting code. We do some
basic stuff and do some things with the shared refs to make sure all that code
works. I had to add a bunch of infrastructure because I needed to be able to
insert items into a fake tree without having to do all the hard work myself,
hopefully this will be usefull in the future. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently qgroups account for space by intercepting delayed ref updates to fs
trees. It does this by adding sequence numbers to delayed ref updates so that
it can figure out how the tree looked before the update so we can adjust the
counters properly. The problem with this is that it does not allow delayed refs
to be merged, so if you say are defragging an extent with 5k snapshots pointing
to it we will thrash the delayed ref lock because we need to go back and
manually merge these things together. Instead we want to process quota changes
when we know they are going to happen, like when we first allocate an extent, we
free a reference for an extent, we add new references etc. This patch
accomplishes this by only adding qgroup operations for real ref changes. We
only modify the sequence number when we need to lookup roots for bytenrs, this
reduces the amount of churn on the sequence number and allows us to merge
delayed refs as we add them most of the time. This patch encompasses a bunch of
architectural changes
1) qgroup ref operations: instead of tracking qgroup operations through the
delayed refs we simply add new ref operations whenever we notice that we need to
when we've modified the refs themselves.
2) tree mod seq: we no longer have this separation of major/minor counters.
this makes the sequence number stuff much more sane and we can remove some
locking that was needed to protect the counter.
3) delayed ref seq: we now read the tree mod seq number and use that as our
sequence. This means each new delayed ref doesn't have it's own unique sequence
number, rather whenever we go to lookup backrefs we inc the sequence number so
we can make sure to keep any new operations from screwing up our world view at
that given point. This allows us to merge delayed refs during runtime.
With all of these changes the delayed ref stuff is a little saner and the qgroup
accounting stuff no longer goes negative in some cases like it was before.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
