When ext4_ext_map_blocks() is called by punch_hole, trace should
trace blocks punched out.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_ext_insert_extent() (respectively ext4_ext_insert_index())
was using EXT_MAX_EXTENT() (resp. EXT_MAX_INDEX()) to determine
how many entries needed to be moved beyond the insertion point.
In practice this means that (320 - I) * 24 bytes were memmove()'d
when I is the insertion point, rather than (#entries - I) * 24 bytes.
This patch uses EXT_LAST_EXTENT() (resp. EXT_LAST_INDEX()) instead
to only move existing entries. The code flow is also simplified
slightly to highlight similarities and reduce code duplication in
the insertion logic.
This patch reduces system CPU consumption by over 25% on a 4kB
synchronous append DIO write workload when used with the
pre-2.6.39 x86_64 memmove() implementation. With the much faster
2.6.39 memmove() implementation we still see a decrease in
system CPU usage between 2% and 7%.
Note that the ext_debug() output changes with this patch, splitting
some log information between entries. Users of the ext_debug() output
should note that the "move %d" units changed from reporting the number
of bytes moved to reporting the number of entries moved.
Signed-off-by: Eric Gouriou <egouriou@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch introduces a fast path in ext4_ext_convert_to_initialized()
for the case when the conversion can be performed by transferring
the newly initialized blocks from the uninitialized extent into
an adjacent initialized extent. Doing so removes the expensive
invocations of memmove() which occur during extent insertion and
the subsequent merge.
In practice this should be the common case for clients performing
append writes into files pre-allocated via
fallocate(FALLOC_FL_KEEP_SIZE). In such a workload performed via
direct IO and when using a suboptimal implementation of memmove()
(x86_64 prior to the 2.6.39 rewrite), this patch reduces kernel CPU
consumption by 32%.
Two new trace points are added to ext4_ext_convert_to_initialized()
to offer visibility into its operations. No exit trace point has
been added due to the multiplicity of return points. This can be
revisited once the upstream cleanup is backported.
Signed-off-by: Eric Gouriou <egouriou@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When we want to convert the unitialized extent in direct write, we can
either do it in ext4_end_io_nolock(AIO case) or in
ext4_ext_direct_IO(non AIO case) and EXT4_I(inode)->cur_aio_dio is a
guard for ext4_ext_map_blocks to find the right case. In e9e3bcecf,
we mistakenly change it by:
- if (io)
+ if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) {
io->flag = EXT4_IO_END_UNWRITTEN;
- else
+ atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
+ } else
ext4_set_inode_state(inode,
EXT4_STATE_DIO_UNWRITTEN);
So now if we map 2 blocks, and the first one set the
EXT_IO_END_UNWRITTEN, the 2nd mapping will set inode state because of
the check for the flag. This is wrong.
Cc: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_ext_next_allocated_block(), the path[depth] might
have a p_ext that is NULL -- see ext4_ext_binsearch(). In
such a case, dereferencing it will crash the machine.
This patch checks for p_ext == NULL in
ext4_ext_next_allocated_block() before dereferencinging it.
Tested using a hand-crafted an inode with eh_entries == 0 in
an extent block, verified that running FIEMAP on it crashes
without this patch, works fine with it.
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When allocated is unsigned it breaks the error handling at the end
of the function when we call:
allocated = ext4_split_extent(...);
if (allocated < 0)
err = allocated;
I've made it a signed int instead of unsigned.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
EOFBLOCK_FL should be updated if called w/o FALLOCATE_FL_KEEP_SIZE
Currently it happens only if new extent was allocated.
TESTCASE:
fallocate test_file -n -l4096
fallocate test_file -l4096
Last fallocate cmd has updated size, but keept EOFBLOCK_FL set. And
fsck will complain about that.
Also remove ping pong in ext4_fallocate() in case of new extents,
where ext4_ext_map_blocks() clear EOFBLOCKS bit, and later
ext4_falloc_update_inode() restore it again.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
- Both callers(truncate and punch_hole) already aligned left end point
so we no longer need split logic here.
- Remove dead duplicated code.
- Call ext4_ext_dirty only after we have updated eh_entries, otherwise
we'll loose entries update. Regression caused by d583fb87a3
266'th testcase in xfstests (http://patchwork.ozlabs.org/patch/120872)
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently code make an impression what grow procedure is very complicated
and some mythical paths, blocks are involved. But in fact grow in depth
it relatively simple procedure:
1) Just create new meta block and copy root data to that block.
2) Convert root from extent to index if old depth == 0
3) Update root block pointer
This patch does:
- Reorganize code to make it more self explanatory
- Do not pass path parameter to new_meta_block() in order to
provoke allocation from inode's group because top-level block
should site closer to it's inode, but not to leaf data block.
[ This happens anyway, due to logic in mballoc; we should drop
the path parameter from new_meta_block() entirely. -- tytso ]
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The third parameter to ext4_free_blocks is a struct buffer_head *. This
parameter should be NULL not 0.
This quiets the sparse noise:
warning: Using plain integer as NULL pointer
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add a sanity check to make sure ix hasn't gone beyond the valid bounds
of the extent block.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_extent_idx.e_block is __le32, so use le32_to_cpu() in
ext4_ext_search_left().
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The comment describing what ext4_ext_search_right() does is incorrect.
We return 0 in *phys when *logical is the 'largest' allocated block,
not smallest.
Fix a few other typos while we're at it.
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Currently, there exists a race between delayed allocated writes and
the writeback when bigalloc feature is in use. The race was because we
wanted to determine what blocks in a cluster are under delayed
allocation and we were using buffer_delayed(bh) check for it. But, the
writeback codepath clears this bit without any synchronization which
resulted in a race and an ext4 warning similar to:
EXT4-fs (ram1): ext4_da_update_reserve_space: ino 13, used 1 with only 0
reserved data blocks
The race existed in two places.
(1) between ext4_find_delalloc_range() and ext4_map_blocks() when called from
writeback code path.
(2) between ext4_find_delalloc_range() and ext4_da_get_block_prep() (where
buffer_delayed(bh) is set.
To fix (1), this patch introduces a new buffer_head state bit -
BH_Da_Mapped. This bit is set under the protection of
EXT4_I(inode)->i_data_sem when we have actually mapped the delayed
allocated blocks during the writeout time. We can now reliably check
for this bit inside ext4_find_delalloc_range() to determine whether
the reservation for the blocks have already been claimed or not.
To fix (2), it was necessary to set buffer_delay(bh) under the
protection of i_data_sem. So, I extracted the very beginning of
ext4_map_blocks into a new function - ext4_da_map_blocks() - and
performed the required setting of bh_delay bit and the quota
reservation under the protection of i_data_sem. These two fixes makes
the checking of buffer_delay(bh) and buffer_da_mapped(bh) consistent,
thus removing the race.
Tested: I was able to reproduce the problem by running 'dd' and
'fsync' in parallel. Also, xfstests sometimes used to reproduce this
race. After the fix both my test and xfstests were successful and no
race (warning message) was observed.
Google-Bug-Id: 4997027
Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds some tracepoints in ext4/extents.c and updates a tracepoint in
ext4/inode.c.
Tested: Built and ran the kernel and verified that these tracepoints work.
Also ran xfstests.
Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
With bigalloc changes, the i_blocks value was not correctly set (it was still
set to number of blocks being used, but in case of bigalloc, we want i_blocks
to represent the number of clusters being used). Since the quota subsystem sets
the i_blocks value, this patch fixes the quota accounting and makes sure that
the i_blocks value is set correctly.
Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When we are truncating (as opposed unlinking) a file, we need to worry
about partial truncates of a file, especially in the light of sparse
files. The changes here make sure that arbitrary truncates of sparse
files works correctly. Yeah, it's messy.
Note that these functions will need to be revisted when the punch
ioctl is integrated --- in fact this commit will probably have merge
conflicts with the punch changes which Allison Henders and the IBM LTC
have been working on. I will need to fix this up when either patch
hits mainline.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If we need to allocate a new block in ext4_ext_map_blocks(), the
function needs to see if the cluster has already been allocated.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
While running extended fsx tests to verify the first
two patches, a similar bug was also found in the
truncate operation.
This bug happens because the truncate routine only zeros
the unblock aligned portion of the last page. This means
that the block aligned portions of the page appearing after
i_size are left unzeroed, and the buffer heads still mapped.
This bug is corrected by using ext4_discard_partial_page_buffers
in the truncate routine to zero the partial page and unmap
the buffer headers.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add debugging information in case jbd2_journal_dirty_metadata() is
called with a buffer_head which didn't have
jbd2_journal_get_write_access() called on it, or if the journal_head
has the wrong transaction in it. In addition, return an error code.
This won't change anything for ocfs2, which will BUG_ON() the non-zero
exit code.
For ext4, the caller of this function is ext4_handle_dirty_metadata(),
and on seeing a non-zero return code, will call __ext4_journal_stop(),
which will print the function and line number of the (buggy) calling
function and abort the journal. This will allow us to recover instead
of bug halting, which is better from a robustness and reliability
point of view.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch fixes a second punch hole bug found by xfstests 127.
This bug happens because punch hole needs to flush the pages
of the hole to avoid race conditions. But if the end of the
hole is in the same page as i_size, the buffer heads beyond
i_size need to be unmapped and the page needs to be zeroed
after it is flushed.
To correct this, the new ext4_discard_partial_page_buffers
routine is used to zero and unmap the partial page
beyond i_size if the end of the hole appears in the same
page as i_size.
The code has also been optimized to set the end of the hole
to the page after i_size if the specified hole exceeds i_size,
and the code that flushes the pages has been simplified.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
This patch addresses a bug found by xfstests 75, 112, 127
when blocksize = 1k
This bug happens because the punch hole code only zeros
out non block aligned regions of the page. This means that if the
blocks are smaller than a page, then the block aligned regions of
the page inside the hole are left un-zeroed, and their buffer heads
are still mapped. This bug is corrected by using
ext4_discard_partial_page_buffers to properly zero the partial page
at the head and tail of the hole, and unmap the corresponding buffer
heads
This patch also addresses a bug reported by Lukas while working on a
new patch to add discard support for loop devices using punch hole.
The bug happened because of the first and last block number
needed to be cast to a larger data type before calculating the
byte offset, but since now we only need the byte offsets of the
pages, we no longer even need to be calculating the byte offsets
of the blocks. The code to do the block offset calculations is
removed in this patch.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
The logical block number in map.l_blk is a __u32, and so before we
shift it left, by the block size, we neeed cast it to a 64-bit size.
Otherwise i_size can be corrupted on an ENOSPC.
# df -T /mnt/mp1
Filesystem Type 1K-blocks Used Available Use% Mounted on
/dev/sda6 ext4 9843276 153056 9190200 2% /mnt/mp1
# fallocate -o 0 -l 2199023251456 /mnt/mp1/testfile
fallocate: /mnt/mp1/testfile: fallocate failed: No space left on device
# stat /mnt/mp1/testfile
File: `/mnt/mp1/testfile'
Size: 4293656576 Blocks: 19380440 IO Block: 4096 regular file
Device: 806h/2054d Inode: 12 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2011-07-25 13:01:31.414490496 +0900
Modify: 2011-07-25 13:01:31.414490496 +0900
Change: 2011-07-25 13:01:31.454490495 +0900
Signed-off-by: Utako Kusaka <u-kusaka@wm.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
--
fs/ext4/extents.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
The old function ext4_ext_rm_idx is used only for truncate case
because it just remove last index in extent-index-block. When punching
hole, it usually needed to remove "middle" index, therefore we must
move indexes which after it forward.
(I create a file with 1 depth extent tree and punch hole in the middle
of it, the last index in index-block strangly gone, so I find out this
bug)
Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The debug message in ext4_ext_insert_extent before moving extent
is incorrect (the "from xx to xx").
Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The argument "inode" in function ext4_ext_next_allocated_block looks useless,
so clean it.
Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If eh_entries is equal to (or greater than) eh_max, the operation of
inserting new extent_idx will make number of entries overflow.
So check eh_entries before inserting the new extent_idx.
Although there is no bug case according the code (function
ext4_ext_insert_index is called by ext4_ext_split and ext4_ext_split
is called only if the index block has free space), the right logic
should be "lookup the capacity before insertion".
Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch avoids an extraneous lookup of the extent cache
in ext4_ext_map_blocks() when the flag
EXT4_GET_BLOCKS_PUNCH_OUT_EXT is absent.
The existing logic was performing the lookup but not making
use of the result. The patch simply reverses the order of evaluation
in the condition.
Since ext4_ext_in_cache() does not initialize newex on misses, bypassing
its invocation does not introduce any new issue in this regard.
Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Eric Gouriou <egouriou@google.com>
This patch removes the extra parameter in ext4_ext_remove_space()
which is no longer needed.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch optimizes the punch hole operation by skipping the
tree walking code that is used by truncate. Since punch hole
is done through map blocks, the path to the extent is already
known in this function, so we do not need to look it up again.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Optimize ext4_ext_insert_extent() by avoiding
ext4_ext_next_leaf_block() when the result is not used/needed.
Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If eh->eh_entries is smaller than eh->eh_max, the routine will
go to the "repeat" and then go to "has_space" directlly ,
since argument "depth" and "eh" are not even changed.
Therefore, goto "has_space" directly and remove redundant "repeat" tag.
Signed-off-by: Robin Dong <sanbai@taobao.com>
Upon corrupted inode or disk failures, we may fail after we already
allocate some blocks from the inode or take some blocks from the
inode's preallocation list, but before we successfully insert the
corresponding extent to the extent tree. In this case, we should free
any allocated blocks and discard the inode's preallocated blocks
because the entries in the inode's preallocation list may be in an
inconsistent state.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
The current implementation of ext4_free_blocks() always calls
dquot_free_block This looks quite sensible in the most cases: blocks
to be freed are associated with inode and were accounted in quota and
i_blocks some time ago.
However, there is a case when blocks to free were not accounted by the
time calling ext4_free_blocks() yet:
1. delalloc is on, write_begin pre-allocated some space in quota
2. write-back happens, ext4 allocates some blocks in ext4_ext_map_blocks()
3. then ext4_ext_map_blocks() gets an error (e.g. ENOSPC) from
ext4_ext_insert_extent() and calls ext4_free_blocks().
In this scenario, ext4_free_blocks() calls dquot_free_block() who, in
turn, decrements i_blocks for blocks which were not accounted yet (due
to delalloc) After clean umount, e2fsck reports something like:
> Inode 21, i_blocks is 5080, should be 5128. Fix<y>?
because i_blocks was erroneously decremented as explained above.
The patch fixes the problem by passing the new flag
EXT4_FREE_BLOCKS_NO_QUOT_UPDATE to ext4_free_blocks(), to request
that the dquot_free_block() call be skipped.
Signed-off-by: Maxim Patlasov <maxim.patlasov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
I found that ext4_ext_find_goal() and ext4_find_near()
share the same code for returning a coloured start block
based on i_block_group.
We can refactor this into a common function so that they
don't diverge in the future.
Thanks to adilger for suggesting the new function name.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In function ext4_ext_insert_index when eh_entries of curp is
bigger than eh_max, error messages will be printed out, but the content
is about logical and ei_block, that's incorret.
Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently we are not marking the extent as the last one
(FIEMAP_EXTENT_LAST) if there is a hole at the end of the file. This is
because we just do not check for it right now and continue searching for
next extent. But at the point we hit the hole at the end of the file, it
is too late.
This commit adds check for the allocated block in subsequent extent and
if there is no more extents (block = EXT_MAX_BLOCKS) just flag the
current one as the last one.
This behaviour has been spotted unintentionally by 252 xfstest, when the
test hangs out, because of wrong loop condition. However on other
filesystems (like xfs) it will exit anyway, because we notice the last
extent flag and exit.
With this patch xfstest 252 does not hang anymore, ext4 fiemap
implementation still reports bad extent type in some cases, however
this seems to be different issue.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Kazuya Mio reported that he was able to hit BUG_ON(next == lblock)
in ext4_ext_put_gap_in_cache() while creating a sparse file in extent
format and fill the tail of file up to its end. We will hit the BUG_ON
when we write the last block (2^32-1) into the sparse file.
The root cause of the problem lies in the fact that we specifically set
s_maxbytes so that block at s_maxbytes fit into on-disk extent format,
which is 32 bit long. However, we are not storing start and end block
number, but rather start block number and length in blocks. It means
that in order to cover extent from 0 to EXT_MAX_BLOCK we need
EXT_MAX_BLOCK+1 to fit into len (because we counting block 0 as well) -
and it does not.
The only way to fix it without changing the meaning of the struct
ext4_extent members is, as Kazuya Mio suggested, to lower s_maxbytes
by one fs block so we can cover the whole extent we can get by the
on-disk extent format.
Also in many places EXT_MAX_BLOCK is used as length instead of maximum
logical block number as the name suggests, it is all a bit messy. So
this commit renames it to EXT_MAX_BLOCKS and change its usage in some
places to actually be maximum number of blocks in the extent.
The bug which this commit fixes can be reproduced as follows:
dd if=/dev/zero of=/mnt/mp1/file bs=<blocksize> count=1 seek=$((2**32-2))
sync
dd if=/dev/zero of=/mnt/mp1/file bs=<blocksize> count=1 seek=$((2**32-1))
Reported-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Make ext4_ext_split() get extents to be moved by calculating in a statement
instead of counting in a loop.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently, an fallocate request of size slightly larger than a power of
2 is turned into two block requests, each a power of 2, with the extra
blocks pre-allocated for future use. When an application calls
fallocate, it already has an idea about how large the file may grow so
there is usually little benefit to reserve extra blocks on the
preallocation list. This reduces disk fragmentation.
Tested: fsstress. Also verified manually that fallocat'ed files are
contiguously laid out with this change (whereas without it they begin at
power-of-2 boundaries, leaving blocks in between). CPU usage of
fallocate is not appreciably higher. In a tight fallocate loop, CPU
usage hovers between 5%-8% with this change, and 5%-7% without it.
Using a simulated file system aging program which the file system to
70%, the percentage of free extents larger than 8MB (as measured by
e2freefrag) increased from 38.8% without this change, to 69.4% with
this change.
Signed-off-by: Vivek Haldar <haldar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds new routines: "ext4_punch_hole" "ext4_ext_punch_hole"
and "ext4_ext_check_cache"
fallocate has been modified to call ext4_punch_hole when the punch hole
flag is passed. At the moment, we only support punching holes in
extents, so this routine is pretty much a wrapper for the ext4_ext_punch_hole
routine.
The ext4_ext_punch_hole routine first completes all outstanding writes
with the associated pages, and then releases them. The unblock
aligned data is zeroed, and all blocks in between are punched out.
The ext4_ext_check_cache routine is very similar to ext4_ext_in_cache
except it accepts a ext4_ext_cache parameter instead of a ext4_extent
parameter. This routine is used by ext4_ext_punch_hole to check and
see if a block in a hole that has been cached. The ext4_ext_cache
parameter is necessary because the members ext4_extent structure are
not large enough to hold a 32 bit value. The existing
ext4_ext_in_cache routine has become a wrapper to this new function.
[ext4 punch hole patch series 5/5 v7]
Signed-off-by: Allison Henderson <achender@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
This patch adds a new flag to ext4_map_blocks() that specifies the
given range of blocks should be punched out. Extents are first
converted to uninitialized extents before they are punched
out. Because punching a hole may require that the extent be split, it
is possible that the splitting may need more blocks than are
available. To deal with this, use of reserved blocks are enabled to
allow the split to proceed.
The routine then returns the number of blocks successfully
punched out.
[ext4 punch hole patch series 4/5 v7]
Signed-off-by: Allison Henderson <achender@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
This patch modifies the truncate routines to support hole punching
Below is a brief summary of the patches changes:
- Added end param to ext_ext4_rm_leaf
This function has been modified to accept an end parameter
which enables it to punch holes in leafs instead of just
truncating them.
- Implemented the "remove head" case in the ext_remove_blocks routine
This routine is used by ext_ext4_rm_leaf to remove the tail
of an extent during a truncate. The new ext_ext4_rm_leaf
routine will now also use it to remove the head of an extent in the
case that the hole covers a region of blocks at the beginning
of an extent.
- Added "end" param to ext4_ext_remove_space routine
This function has been modified to accept a stop parameter, which
is passed through to ext4_ext_rm_leaf.
[ext4 punch hole patch series 3/5 v6]
Signed-off-by: Allison Henderson <achender@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds an allocation request flag to the ext4_has_free_blocks
function which enables the use of reserved blocks. This will allow a
punch hole to proceed even if the disk is full. Punching a hole may
require additional blocks to first split the extents.
Because ext4_has_free_blocks is a low level function, the flag needs
to be passed down through several functions listed below:
ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
ext4_ext_split
ext4_ext_new_meta_block
ext4_mb_new_blocks
ext4_claim_free_blocks
ext4_has_free_blocks
[ext4 punch hole patch series 1/5 v7]
Signed-off-by: Allison Henderson <achender@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
To get delayed-extent information, ext4_ext_fiemap_cb() looks up
pagecache, it thus collects information starting from a page's
head block.
If blocksize < pagesize, the beginning blocks of a page may lies
before the request range. So ext4_ext_fiemap_cb() should proceed
ignoring them, because they has been handled before. If no mapped
buffer in the range is found in the 1st page, we need to look up
the 2nd page, otherwise delayed-extents after a hole will be ignored.
Without this patch, xfstests 225 will hung on ext4 with 1K block.
Reported-by: Amir Goldstein <amir73il@users.sourceforge.net>
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_ext_truncate() should not invoke up_write(&EXT4_I(inode)->i_data_sem)
when ext4_orphan_add() returns an error, as it hasn't performed a
down_write() yet. This trivial patch fixes this by moving the up_write()
invocation above the out_stop label.
Signed-off-by: Eric Gouriou <egouriou@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The number of hits and misses for each filesystem is exposed in
/sys/fs/ext4/<dev>/extent_cache_{hits, misses}.
Tested: fsstress, manual checks.
Signed-off-by: Vivek Haldar <haldar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch addresses bugs found while testing punch hole
with the fsx test. The patch corrects the number of blocks
that are zeroed out while splitting an extent, and also corrects
the return value to return the number of blocks split out, instead
of the number of blocks zeroed out.
This patch has been tested in addition to the following patches:
[Ext4 punch hole v7]
[XFS Tests Punch Hole 1/1 v2] Add Punch Hole Testing to FSX
The test ran successfully for 24 hours.
Signed-off-by: Allison Henderson <achender@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add two functions: ext4_split_extent_at(), which splits an extent into
two extents at given logical block, and ext4_split_extent() which
splits an extent into three extents.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Tested-by: Allison Henderson <achender@linux.vnet.ibm.com>
1) Rename ext4_ext_try_to_merge() to ext4_ext_try_to_merge_right().
2) Add a new function ext4_ext_try_to_merge() which tries to merge
an extent both left and right.
3) Use the new function in ext4_ext_convert_unwritten_endio() and
ext4_ext_insert_extent().
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Tested-by: Allison Henderson <achender@linux.vnet.ibm.com>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (43 commits)
ext4: fix a BUG in mb_mark_used during trim.
ext4: unused variables cleanup in fs/ext4/extents.c
ext4: remove redundant set_buffer_mapped() in ext4_da_get_block_prep()
ext4: add more tracepoints and use dev_t in the trace buffer
ext4: don't kfree uninitialized s_group_info members
ext4: add missing space in printk's in __ext4_grp_locked_error()
ext4: add FITRIM to compat_ioctl.
ext4: handle errors in ext4_clear_blocks()
ext4: unify the ext4_handle_release_buffer() api
ext4: handle errors in ext4_rename
jbd2: add COW fields to struct jbd2_journal_handle
jbd2: add the b_cow_tid field to journal_head struct
ext4: Initialize fsync transaction ids in ext4_new_inode()
ext4: Use single thread to perform DIO unwritten convertion
ext4: optimize ext4_bio_write_page() when no extent conversion is needed
ext4: skip orphan cleanup if fs has unknown ROCOMPAT features
ext4: use the nblocks arg to ext4_truncate_restart_trans()
ext4: fix missing iput of root inode for some mount error paths
ext4: make FIEMAP and delayed allocation play well together
ext4: suppress verbose debugging information if malloc-debug is off
...
Fi up conflicts in fs/ext4/super.c due to workqueue changes
- Add more ext4 tracepoints.
- Change ext4 tracepoints to use dev_t field with MAJOR/MINOR macros
so that we can save 4 bytes in the ring buffer on some platforms.
- Add sync_mode to ext4_da_writepages, ext4_da_write_pages, and
ext4_da_writepages_result tracepoints. Also remove for_reclaim
field from ext4_da_writepages since it is usually not very useful.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Fix the FIEMAP ioctl so that it returns all of the page ranges which
are still subject to delayed allocation. We were missing some cases
if the file was sparse.
Reported by Chris Mason <chris.mason@oracle.com>:
>We've had reports on btrfs that cp is giving us files full of zeros
>instead of actually copying them. It was tracked down to a bug with
>the btrfs fiemap implementation where it was returning holes for
>delalloc ranges.
>
>Newer versions of cp are trusting fiemap to tell it where the holes
>are, which does seem like a pretty neat trick.
>
>I decided to give xfs and ext4 a shot with a few tests cases too, xfs
>passed with all the ones btrfs was getting wrong, and ext4 got the basic
>delalloc case right.
>$ mkfs.ext4 /dev/xxx
>$ mount /dev/xxx /mnt
>$ dd if=/dev/zero of=/mnt/foo bs=1M count=1
>$ fiemap-test foo
>ext: 0 logical: [ 0.. 255] phys: 0.. 255
>flags: 0x007 tot: 256
>
>Horray! But once we throw a hole in, things go bad:
>$ mkfs.ext4 /dev/xxx
>$ mount /dev/xxx /mnt
>$ dd if=/dev/zero of=/mnt/foo bs=1M count=1 seek=1
>$ fiemap-test foo
>< no output >
>
>We've got a delalloc extent after the hole and ext4 fiemap didn't find
>it. If I run sync to kick the delalloc out:
>$sync
>$ fiemap-test foo
>ext: 0 logical: [ 256.. 511] phys: 34048.. 34303
>flags: 0x001 tot: 256
>
>fiemap-test is sitting in my /usr/local/bin, and I have no idea how it
>got there. It's full of pretty comments so I know it isn't mine, but
>you can grab it here:
>
>http://oss.oracle.com/~mason/fiemap-test.c
>
>xfsqa has a fiemap program too.
After Fix, test results are as follows:
ext: 0 logical: [ 256.. 511] phys: 0.. 255
flags: 0x007 tot: 256
ext: 0 logical: [ 256.. 511] phys: 33280.. 33535
flags: 0x001 tot: 256
$ mkfs.ext4 /dev/xxx
$ mount /dev/xxx /mnt
$ dd if=/dev/zero of=/mnt/foo bs=1M count=1 seek=1
$ sync
$ dd if=/dev/zero of=/mnt/foo bs=1M count=1 seek=3
$ dd if=/dev/zero of=/mnt/foo bs=1M count=1 seek=5
$ fiemap-test foo
ext: 0 logical: [ 256.. 511] phys: 33280.. 33535
flags: 0x000 tot: 256
ext: 1 logical: [ 768.. 1023] phys: 0.. 255
flags: 0x006 tot: 256
ext: 2 logical: [ 1280.. 1535] phys: 0.. 255
flags: 0x007 tot: 256
Tested-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch fixes the warning "Using plain integer as NULL pointer",
generated by sparse, by replacing the offending 0s with NULL.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4 has a data corruption case when doing non-block-aligned
asynchronous direct IO into a sparse file, as demonstrated
by xfstest 240.
The root cause is that while ext4 preallocates space in the
hole, mappings of that space still look "new" and
dio_zero_block() will zero out the unwritten portions. When
more than one AIO thread is going, they both find this "new"
block and race to zero out their portion; this is uncoordinated
and causes data corruption.
Dave Chinner fixed this for xfs by simply serializing all
unaligned asynchronous direct IO. I've done the same here.
The difference is that we only wait on conversions, not all IO.
This is a very big hammer, and I'm not very pleased with
stuffing this into ext4_file_write(). But since ext4 is
DIO_LOCKING, we need to serialize it at this high level.
I tried to move this into ext4_ext_direct_IO, but by then
we have the i_mutex already, and we will wait on the
work queue to do conversions - which must also take the
i_mutex. So that won't work.
This was originally exposed by qemu-kvm installing to
a raw disk image with a normal sector-63 alignment. I've
tested a backport of this patch with qemu, and it does
avoid the corruption. It is also quite a lot slower
(14 min for package installs, vs. 8 min for well-aligned)
but I'll take slow correctness over fast corruption any day.
Mingming suggested that we can track outstanding
conversions, and wait on those so that non-sparse
files won't be affected, and I've implemented that here;
unaligned AIO to nonsparse files won't take a perf hit.
[tytso@mit.edu: Keep the mutex as a hashed array instead
of bloating the ext4 inode]
[tytso@mit.edu: Fix up namespace issues so that global
variables are protected with an "ext4_" prefix.]
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit. Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes. On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions. Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.
This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Instead of various home grown checks that might need updates for new
flags just check for any bit outside the mask of the features supported
by the filesystem. This makes the check future proof for any newly
added flag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (41 commits)
fs: add documentation on fallocate hole punching
Gfs2: fail if we try to use hole punch
Btrfs: fail if we try to use hole punch
Ext4: fail if we try to use hole punch
Ocfs2: handle hole punching via fallocate properly
XFS: handle hole punching via fallocate properly
fs: add hole punching to fallocate
vfs: pass struct file to do_truncate on O_TRUNC opens (try #2)
fix signedness mess in rw_verify_area() on 64bit architectures
fs: fix kernel-doc for dcache::prepend_path
fs: fix kernel-doc for dcache::d_validate
sanitize ecryptfs ->mount()
switch afs
move internal-only parts of ncpfs headers to fs/ncpfs
switch ncpfs
switch 9p
pass default dentry_operations to mount_pseudo()
switch hostfs
switch affs
switch configfs
...
Ext4 doesn't have the ability to punch holes yet, so make sure we return
EOPNOTSUPP if we try to use hole punching through fallocate. This support can
be added later. Thanks,
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Since check_eofblocks_fl() only uses the m_lblk portion of the map
structure, we may as well pass that directly, rather than passing the
entire map, which IMHO obfuscates what parameters check_eofblocks_fl()
cares about. Not a big deal, but seems tidier and less confusing, to
me.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Ted first found the bug when running 2.6.36 kernel with dioread_nolock
mount option that xfstests #13 complained about wrong file size during fsck.
However, the bug exists in the older kernels as well although it is
somehow harder to trigger.
The problem is that ext4_end_io_work() can happen after we have truncated an
inode to a smaller size. Then when ext4_end_io_work() calls
ext4_convert_unwritten_extents(), we may reallocate some blocks that have
been truncated, so the inode size becomes inconsistent with the allocated
blocks.
The following patch flushes the i_completed_io_list during truncate to reduce
the risk that some pending end_io requests are executed later and convert
already truncated blocks to initialized.
Note that although the fix helps reduce the problem a lot there may still
be a race window between vmtruncate() and ext4_end_io_work(). The fundamental
problem is that if vmtruncate() is called without either i_mutex or i_alloc_sem
held, it can race with an ongoing write request so that the io_end request is
processed later when the corresponding blocks have been truncated.
Ted and I have discussed the problem offline and we saw a few ways to fix
the race completely:
a) We guarantee that i_mutex lock and i_alloc_sem write lock are both hold
whenever vmtruncate() is called. The i_mutex lock prevents any new write
requests from entering writeback and the i_alloc_sem prevents the race
from ext4_page_mkwrite(). Currently we hold both locks if vmtruncate()
is called from do_truncate(), which is probably the most common case.
However, there are places where we may call vmtruncate() without holding
either i_mutex or i_alloc_sem. I would like to ask for other people's
opinions on what locks are expected to be held before calling vmtruncate().
There seems a disagreement among the callers of that function.
b) We change the ext4 write path so that we change the extent tree to contain
the newly allocated blocks and update i_size both at the same time --- when
the write of the data blocks is completed.
c) We add some additional locking to synchronize vmtruncate() and
ext4_end_io_work(). This approach may have performance implications so we
need to be careful.
All of the above proposals may require more substantial changes, so
we may consider to take the following patch as a bandaid.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We can encode the ec_type information by using ee_len == 0 to denote
EXT4_EXT_CACHE_NO, ee_start == 0 to denote EXT4_EXT_CACHE_GAP, and if
neither is true, then the cache type must be EXT4_EXT_CACHE_EXTENT.
This allows us to reduce the size of ext4_ext_inode by another 8
bytes. (ec_type is 4 bytes, plus another 4 bytes of padding)
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This fixes a number of places where we used sector_t instead of
ext4_lblk_t for logical blocks, which for ext4 are still 32-bit data
types. No point wasting space in the ext4_inode_info structure, and
requiring 64-bit arithmetic on 32-bit systems, when it isn't
necessary.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_ext_find_goal() returns an ideal physical block number that the block
allocator tries to allocate first. However, if a required file offset is
smaller than the existing extent's one, ext4_ext_find_goal() returns
a wrong block number because it may overflow at
"block - le32_to_cpu(ex->ee_block)". This patch fixes the problem.
ext4_ext_find_goal() will also return a wrong block number in case
a file offset of the existing extent is too big. In this case,
the ideal physical block number is fixed in ext4_mb_initialize_context(),
so it's no problem.
reproduce:
# dd if=/dev/zero of=/mnt/mp1/tmp bs=127M count=1 oflag=sync
# dd if=/dev/zero of=/mnt/mp1/file bs=512K count=1 seek=1 oflag=sync
# filefrag -v /mnt/mp1/file
Filesystem type is: ef53
File size of /mnt/mp1/file is 1048576 (256 blocks, blocksize 4096)
ext logical physical expected length flags
0 128 67456 128 eof
/mnt/mp1/file: 2 extents found
# rm -rf /mnt/mp1/tmp
# echo $((512*4096)) > /sys/fs/ext4/loop0/mb_stream_req
# dd if=/dev/zero of=/mnt/mp1/file bs=512K count=1 oflag=sync conv=notrunc
result (linux-2.6.37-rc2 + ext4 patch queue):
# filefrag -v /mnt/mp1/file
Filesystem type is: ef53
File size of /mnt/mp1/file is 1048576 (256 blocks, blocksize 4096)
ext logical physical expected length flags
0 0 33280 128
1 128 67456 33407 128 eof
/mnt/mp1/file: 2 extents found
result(apply this patch):
# filefrag -v /mnt/mp1/file
Filesystem type is: ef53
File size of /mnt/mp1/file is 1048576 (256 blocks, blocksize 4096)
ext logical physical expected length flags
0 0 66560 128
1 128 67456 66687 128 eof
/mnt/mp1/file: 2 extents found
Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When I compiled 2.6.36-rc3 kernel with EXT4FS_DEBUG definition, I got
the following compile error.
CC [M] fs/ext4/extents.o
fs/ext4/extents.c: In function 'ext4_fallocate':
fs/ext4/extents.c:3772: error: 'block' undeclared (first use in this function)
fs/ext4/extents.c:3772: error: (Each undeclared identifier is reported only once
fs/ext4/extents.c:3772: error: for each function it appears in.)
make[2]: *** [fs/ext4/extents.o] Error 1
The patch fixes this problem.
Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cleanup namespace leaks from fs/ext4 and the inline trivial functions
ext4_{ext,idx}_pblock() and ext4_{ext,idx}_store_pblock() since the
code size actually shrinks when we make these functions inline,
they're so trivial.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
These functions have no need to be exported beyond file context.
No functions needed to be moved for this commit; just some function
declarations changed to be static and removed from header files.
(A similar patch was submitted by Eric Sandeen, but I wanted to handle
code movement in separate patches to make sure code changes didn't
accidentally get dropped.)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Call the block I/O layer directly instad of going through the buffer
layer. This should give us much better performance and scalability,
as well as lowering our CPU utilization when doing buffered writeback.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Change ext4_ext_zeroout to use sb_issue_zeroout instead of its
own approach to zero out extents.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
It turns out we have several problems with how EOFBLOCKS_FL is
handled. First of all, there was a fencepost error where we were not
clearing the EOFBLOCKS_FL when fill in the last uninitialized block,
but rather when we allocate the next block _after_ the uninitalized
block. Secondly we were not testing to see if we needed to clear the
EOFBLOCKS_FL when writing to the file O_DIRECT or when were converting
an uninitialized block (which is the most common case).
Google-Bug-Id: 2928259
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (40 commits)
ext4: Adding error check after calling ext4_mb_regular_allocator()
ext4: Fix dirtying of journalled buffers in data=journal mode
ext4: re-inline ext4_rec_len_(to|from)_disk functions
jbd2: Remove t_handle_lock from start_this_handle()
jbd2: Change j_state_lock to be a rwlock_t
jbd2: Use atomic variables to avoid taking t_handle_lock in jbd2_journal_stop
ext4: Add mount options in superblock
ext4: force block allocation on quota_off
ext4: fix freeze deadlock under IO
ext4: drop inode from orphan list if ext4_delete_inode() fails
ext4: check to make make sure bd_dev is set before dereferencing it
jbd2: Make barrier messages less scary
ext4: don't print scary messages for allocation failures post-abort
ext4: fix EFBIG edge case when writing to large non-extent file
ext4: fix ext4_get_blocks references
ext4: Always journal quota file modifications
ext4: Fix potential memory leak in ext4_fill_super
ext4: Don't error out the fs if the user tries to make a file too big
ext4: allocate stripe-multiple IOs on stripe boundaries
ext4: move aio completion after unwritten extent conversion
...
Fix up conflicts in fs/ext4/inode.c as per Ted.
Fix up xfs conflicts as per earlier xfs merge.
No real bugs found, just removed some dead code.
Found by gcc 4.6's new warnings.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If i_data_sem was internally dropped due to transaction restart, it is
necessary to restart path look-up because extents tree was possibly
modified by ext4_get_block().
https://bugzilla.kernel.org/show_bug.cgi?id=15827
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Dimitry Monakhov discovered an edge case where it was possible for the
EXT4_EOFBLOCKS_FL flag could get cleared unnecessarily. This is true;
I have a test case that can be exercised via downloading and
decompressing the file:
wget ftp://ftp.kernel.org/pub/linux/kernel/people/tytso/ext4-testcases/eofblocks-fl-test-case.img.bz2
bunzip2 eofblocks-fl-test-case.img
dd if=/dev/zero of=eofblocks-fl-test-case.img bs=1k seek=17925 bs=1k count=1 conv=notrunc
However, triggering it in real life is highly unlikely since it
requires an extremely fragmented sparse file with a hole in exactly
the right place in the extent tree. (It actually took quite a bit of
work to generate this test case.) Still, it's nice to get even
extreme corner cases to be correct, so this patch makes sure that we
don't clear the EXT4_EOFBLOCKS_FL incorrectly even in this corner
case.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the EOFBLOCK_FL flag is set when it should not be and the inode is
zero length, then eh_entries is zero, and ex is NULL, so dereferencing
ex to print ex->ee_block causes a kernel OOPS in
ext4_ext_map_blocks().
On top of that, the error message which is printed isn't very helpful.
So we fix this by printing something more explanatory which doesn't
involve trying to print ex->ee_block.
Addresses-Google-Bug: #2655740
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
At several places we modify EXT4_I(inode)->i_flags without holding
i_mutex (ext4_do_update_inode, ...). These modifications are racy and
we can lose updates to i_flags. So convert handling of i_flags to use
bitops which are atomic.
https://bugzilla.kernel.org/show_bug.cgi?id=15792
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
EXT4_ERROR_INODE() tends to provide better error information and in a
more consistent format. Some errors were not even identifying the inode
or directory which was corrupted, which made them not very useful.
Addresses-Google-Bug: #2507977
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This saves a huge amount of stack space by avoiding unnecesary struct
buffer_head's from being allocated on the stack.
In addition, to make the code easier to understand, collapse and
refactor ext4_get_block(), ext4_get_block_write(),
noalloc_get_block_write(), into a single function.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Jack up ext4_get_blocks() and add a new function, ext4_map_blocks()
which uses a much smaller structure, struct ext4_map_blocks which is
20 bytes, as opposed to a struct buffer_head, which nearly 5 times
bigger on an x86_64 machine. By switching things to use
ext4_map_blocks(), we can save stack space by using ext4_map_blocks()
since we can avoid allocating a struct buffer_head on the stack.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently using posix_fallocate one can bypass an RLIMIT_FSIZE limit
and create a file larger than the limit. Add a check for that.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Amit Arora <aarora@in.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The extents code will sometimes zero out blocks and mark them as
initialized instead of splitting an extent into several smaller ones.
This optimization however, causes problems if the extent is beyond
i_size because fsck will complain if there are uninitialized blocks
after i_size as this can not be distinguished from an inode that has
an incorrect i_size field.
https://bugzilla.kernel.org/show_bug.cgi?id=15742
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When EIO occurs after bio is submitted, there is no memory free
operation for bio, which results in memory leakage. And there is also
no check against bio_alloc() for bio.
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Jing Zhang <zj.barak@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Calls to ext4_get_inode_loc() returns with a reference to a buffer
head in iloc->bh. The callers of this function in ext4_write_inode()
when in no journal mode and in ext4_xattr_fiemap() don't release the
buffer head after using it.
Addresses-Google-Bug: #2548165
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
There are duplicate macro definitions of in_range() in mballoc.h and
balloc.c. This consolidates these two definitions into ext4.h, and
changes extents.c to use in_range() as well.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger@sun.com>
This is a cleanup and simplification patch which takes some open-coded
calculations to calculate the first block number of a group and
converts them to use the (already defined) ext4_group_first_block_no()
function.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger@sun.com>
Convert a bunch of BUG_ONs to emit a ext4_error() message and return
EIO. This is a first pass and most notably does _not_ cover
mballoc.c, which is a morass of void functions.
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Allocate uninitialized extent before ext4 buffer write and
convert the extent to initialized after io completes.
The purpose is to make sure an extent can only be marked
initialized after it has been written with new data so
we can safely drop the i_mutex lock in ext4 DIO read without
exposing stale data. This helps to improve multi-thread DIO
read performance on high-speed disks.
Skip the nobh and data=journal mount cases to make things simple for now.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit renames some of the direct I/O's block allocation flags,
variables, and functions introduced in Mingming's "Direct IO for holes
and fallocate" patches so that they can be used by ext4's buffered
write path as well. Also changed the related function comments
accordingly to cover both direct write and buffered write cases.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
fallocate() may potentially instantiate blocks past EOF, depending
on the flags used when it is called.
e2fsck currently has a test for blocks past i_size, and it
sometimes trips up - noticeably on xfstests 013 which runs fsstress.
This patch from Jiayang does fix it up - it (along with
e2fsprogs updates and other patches recently from Aneesh) has
survived many fsstress runs in a row.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_fiemap() rounds the length of the requested range down to
blocksize, which is is not the true number of blocks that cover the
requested region. This problem is especially impressive if the user
requests only the first byte of a file: not a single extent will be
reported.
We fix this by calculating the last block of the region and then
subtract to find the number of blocks in the extents.
Signed-off-by: Leonard Michlmayr <leonard.michlmayr@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Just a pet peeve of mine; we had a mishash of calls with either __func__
or "function_name" and the latter tends to get out of sync.
I think it's easier to just hide the __func__ in a macro, and it'll
be consistent from then on.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
At several places we modify EXT4_I(inode)->i_state without holding
i_mutex (ext4_release_file, ext4_bmap, ext4_journalled_writepage,
ext4_do_update_inode, ...). These modifications are racy and we can
lose updates to i_state. So convert handling of i_state to use bitops
which are atomic.
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The "offset" member in ext4_io_end holds bytes, not blocks, so
ext4_lblk_t is wrong - and too small (u32).
This caused the async i/o writes to sparse files beyond 4GB to fail
when they wrapped around to 0.
Also fix up the type of arguments to ext4_convert_unwritten_extents(),
it gets ssize_t from ext4_end_aio_dio_nolock() and
ext4_ext_direct_IO().
Reported-by: Giel de Nijs <giel@vectorwise.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
We should update reserve space if it is delalloc buffer
and that is indicated by EXT4_GET_BLOCKS_DELALLOC_RESERVE flag.
So use EXT4_GET_BLOCKS_DELALLOC_RESERVE in place of
EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
When we fallocate a region of the file which we had recently written,
and which is still in the page cache marked as delayed allocated blocks
we need to make sure we don't do the quota update on writepage path.
This is because the needed quota updated would have already be done
by fallocate.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
In the past, ext4_calc_metadata_amount(), and its sub-functions
ext4_ext_calc_metadata_amount() and ext4_indirect_calc_metadata_amount()
badly over-estimated the number of metadata blocks that might be
required for delayed allocation blocks. This didn't matter as much
when functions which managed the reserved metadata blocks were more
aggressive about dropping reserved metadata blocks as delayed
allocation blocks were written, but unfortunately they were too
aggressive. This was fixed in commit 0637c6f, but as a result the
over-estimation by ext4_calc_metadata_amount() would lead to reserving
2-3 times the number of pending delayed allocation blocks as
potentially required metadata blocks. So if there are 1 megabytes of
blocks which have been not yet been allocation, up to 3 megabytes of
space would get reserved out of the user's quota and from the file
system free space pool until all of the inode's data blocks have been
allocated.
This commit addresses this problem by much more accurately estimating
the number of metadata blocks that will be required. It will still
somewhat over-estimate the number of blocks needed, since it must make
a worst case estimate not knowing which physical blocks will be
needed, but it is much more accurate than before.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This fixes a bug (found by Curt Wohlgemuth) in which new blocks
returned from an extent created with ext4_ext_zeroout() can have dirty
metadata still associated with them.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch fixes the Kernel BZ #14286. When the address of an extent
corresponding to a valid block is corrupted, a -EIO should be reported
instead of a BUG(). This situation should not normally not occur
except in the case of a corrupted filesystem. If however it does,
then the system should not panic directly but depending on the mount
time options appropriate action should be taken. If the mount options
so permit, the I/O should be gracefully aborted by returning a -EIO.
http://bugzilla.kernel.org/show_bug.cgi?id=14286
Signed-off-by: Surbhi Palande <surbhi.palande@canonical.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We cannot rely on buffer dirty bits during fsync because pdflush can come
before fsync is called and clear dirty bits without forcing a transaction
commit. What we do is that we track which transaction has last changed
the inode and which transaction last changed allocation and force it to
disk on fsync.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently all quota block reservation macros contains hard-coded "2"
aka MAXQUOTAS value. This is no good because in some places it is not
obvious to understand what does this digit represent. Let's introduce
new macro with self descriptive name.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Acked-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add the facility for ext4_forget() to be called from
ext4_free_blocks(). This simplifies the code in a large number of
places, and centralizes most of the work of calling ext4_forget() into
a single place.
Also fix a bug in the extents migration code; it wasn't calling
ext4_forget() when releasing the indirect blocks during the
conversion. As a result, if the system cashed during or shortly after
the extents migration, and the released indirect blocks get reused as
data blocks, the journal replay would corrupt the data blocks. With
this new patch, fixing this bug was as simple as adding the
EXT4_FREE_BLOCKS_FORGET flags to the call to ext4_free_blocks().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
When an inode gets unlinked, the functions ext4_clear_blocks() and
ext4_remove_blocks() call ext4_forget() for all the buffer heads
corresponding to the deleted inode's data blocks. If the inode is a
directory or a symlink, the is_metadata parameter must be non-zero so
ext4_forget() will revoke them via jbd2_journal_revoke(). Otherwise,
if these blocks are reused for a data file, and the system crashes
before a journal checkpoint, the journal replay could end up
corrupting these data blocks.
Thanks to Curt Wohlgemuth for pointing out potential problems in this
area.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
To prepare for a direct I/O write, we need to split the unwritten
extents before submitting the I/O. When no extents needed to be
split, ext4_split_unwritten_extents() was incorrectly returning 0
instead of the size of uninitialized extents. This bug caused the
wrong return value sent back to VFS code when it gets called from
async IO path, leading to an unnecessary fall back to buffered IO.
This bug also hid the fact that the check to see whether or not a
split would be necessary was incorrect; we can only skip splitting the
extent if the write completely covers the uninitialized extent.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
At the end of direct I/O operation, ext4_ext_direct_IO() always called
ext4_convert_unwritten_extents(), regardless of whether there were any
unwritten extents involved in the I/O or not.
This commit adds a state flag so that ext4_ext_direct_IO() only calls
ext4_convert_unwritten_extents() when necessary.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
After a direct I/O request covering an uninitalized extent (i.e.,
created using the fallocate system call) or a hole in a file, ext4
will convert the uninitialized extent so it is marked as initialized
by calling ext4_convert_unwritten_extents(). This function returns
zero on success.
This return value was getting returned by ext4_direct_IO(); however
the file system's direct_IO function is supposed to return the number
of bytes read or written on a success. By returning zero, it confused
the direct I/O code into falling back to buffered I/O unnecessarily.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
There are a number of kernel printk's which are printed when an ext4
filesystem is mounted and unmounted. Disable them to economize space
in the system logs. In addition, disabling the mballoc stats by
default saves a number of unneeded atomic operations for every block
allocation or deallocation.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
For async direct IO that covers holes or fallocate, the end_io
callback function now queued the convertion work on workqueue but
don't flush the work rightaway as it might take too long to afford.
But when fsync is called after all the data is completed, user expects
the metadata also being updated before fsync returns.
Thus we need to flush the conversion work when fsync() is called.
This patch keep track of a listed of completed async direct io that
has a work queued on workqueue. When fsync() is called, it will go
through the list and do the conversion.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
When writing into an unitialized extent via direct I/O, and the direct
I/O doesn't exactly cover the unitialized extent, split the extent
into uninitialized and initialized extents before submitting the I/O.
This avoids needing to deal with an ENOSPC error in the end_io
callback that gets used for direct I/O.
When the IO is complete, the written extent will be marked as initialized.
Singed-Off-By: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The extents sanity-checking code depends on the ext4_ext_space_*()
functions returning the maximum alloable size for eh_max; however,
when the debugging #ifdef AGGRESSIVE_TEST is enabled to test the
extent tree handling code, this prevents a normally created ext4
filesystem from being mounted with the errors:
Aug 26 15:43:50 bsd086 kernel: [ 96.070277] EXT4-fs error (device sda8): ext4_ext_check_inode: bad header/extent in inode #8: too large eh_max - magic f30a, entries 1, max 4(3), depth 0(0)
Aug 26 15:43:50 bsd086 kernel: [ 96.070526] EXT4-fs (sda8): no journal found
Bug reported by Akira Fujita.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
During truncate we are sometimes forced to start a new transaction as
the amount of blocks to be journaled is both quite large and hard to
predict. So far we restarted a transaction while holding i_data_sem
and that violates lock ordering because i_data_sem ranks below a
transaction start (and it can lead to a real deadlock with
ext4_get_blocks() mapping blocks in some page while having a
transaction open).
We fix the problem by dropping the i_data_sem before restarting the
transaction and acquire it afterwards. It's slightly subtle that this
works:
1) By the time ext4_truncate() is called, all the page cache for the
truncated part of the file is dropped so get_block() should not be
called on it (we only have to invalidate extent cache after we
reacquire i_data_sem because some extent from not-truncated part could
extend also into the part we are going to truncate).
2) Writes, migrate or defrag hold i_mutex so they are stopped for all
the time of the truncate.
This bug has been found and analyzed by Theodore Tso <tytso@mit.edu>.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_ext_show_leaf() will display the leaf extents when extent
debugging is enabled.
Printing out the unwritten bit is useful for debugging unwritten
extent, allow us to see the unwritten extents vs written extents,
after the unwritten extents are splitted or converted.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
When EXT_DEBUG is enabled I received the following compile warning on
PPC64:
CC [M] fs/ext4/inode.o
CC [M] fs/ext4/extents.o
fs/ext4/extents.c: In function ‘ext4_ext_rm_leaf’:
fs/ext4/extents.c:2097: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 2 has type ‘ext4_lblk_t’
fs/ext4/extents.c: In function ‘ext4_ext_get_blocks’:
fs/ext4/extents.c:2789: warning: format ‘%u’ expects type ‘unsigned int’, but argument 4 has type ‘long unsigned int’
fs/ext4/extents.c:2852: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 3 has type ‘ext4_lblk_t’
fs/ext4/extents.c:2953: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 4 has type ‘unsigned int’
CC [M] fs/ext4/migrate.o
The patch fixes compile warning.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Index: linux-2.6.31-rc4/fs/ext4/extents.c
===================================================================
When we have space in the extent tree leaf node we should be able to
insert the extent with much less journal credits. The code was doing
proper calculation but missed a return statement.
Reported-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The EXT4_IOC_MOVE_EXT exchanges the blocks between orig_fd and donor_fd,
and then write the file data of orig_fd to donor_fd.
ext4_mext_move_extent() is the main fucntion of ext4 online defrag,
and this patch includes all functions related to ext4 online defrag.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: Takashi Sato <t-sato@yk.jp.nec.com>
Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The unitialized bit was not properly getting preserved in in an extent
which is partially truncated because the it was geting set to the
value of the first extent to be removed or truncated as part of the
truncate operation, and if there are multiple extents are getting
removed or modified as part of the truncate operation, it is only the
last extent which will might be partially truncated, and its
uninitalized bit is not necessarily the same as the first extent to be
truncated.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Get rid of EXTEND_DISKSIZE flag of ext4_get_blocks_handle(). This
seems to be a relict from some old days and setting disksize in this
function does not make much sense. Currently it was set only by
ext4_getblk(). Since the parameter has some effect only if create ==
1, it is easy to check by grepping through the sources that the three
callers which end up calling ext4_getblk() with create == 1
(ext4_append, ext4_quota_write, ext4_mkdir) do the right thing and set
disksize themselves.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Not sure why I put this in as down_write originally; all we are
doing is walking the tree, nothing will change under us and
concurrent reads should be no problem.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
To catch filesystem bugs or corruption which could lead to the
filesystem getting severly damaged, this patch adds a facility for
tracking all of the filesystem metadata blocks by contiguous regions
in a red-black tree. This allows quick searching of the tree to
locate extents which might overlap with filesystem metadata blocks.
This facility is also used by the multi-block allocator to assure that
it is not allocating blocks out of the system zone, as well as by the
routines used when reading indirect blocks and extents information
from disk to make sure their contents are valid.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The functions ext4_get_blocks(), ext4_ext_get_blocks(), and
ext4_ind_get_blocks() used an ad-hoc set of integer variables used as
boolean flags passed in as arguments. Use a single flags parameter
and a setandard set of bitfield flags instead. This saves space on
the call stack, and it also makes the code a bit more understandable.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Another function rename for clarity's sake. The _wrap prefix simply
confuses people, and didn't add much people trying to follow the code
paths.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the file's blocks have not yet been allocated because of delayed
allocation, the length of the extent returned by fiemap is incorrect.
This commit fixes this bug.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Carl Henrik Lunde reported and debugged this; the test for the
last allocated block was comparing bytes to blocks in this test:
if (logical + length - 1 == EXT_MAX_BLOCK ||
ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK)
flags |= FIEMAP_EXTENT_LAST;
so any extent which ended right at 4G was stopping the extent
walk. Just replacing these values with the extent block &
length should fix it.
Also give blksize_bits a saner type, and reverse the order
of the tests to make the more likely case tested first.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Tested-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Setting BH_Unwritten buffer_heads as BH_Mapped avoids multiple
(unnecessary) calls to get_block() during the call to the write(2)
system call. Setting BH_Unwritten buffer heads as BH_Mapped requires
that the writepages() functions can handle BH_Unwritten buffer_heads.
After this commit, things work as follows:
ext4_ext_get_block() returns unmapped, unwritten, buffer head when
called with create = 0 for prealloc space. This makes sure we handle
the read path and non-delayed allocation case correctly. Even though
the buffer head is marked unmapped we have valid b_blocknr and b_bdev
values in the buffer_head.
ext4_da_get_block_prep() called for block resrevation will now return
mapped, unwritten, new buffer_head for prealloc space. This avoids
multiple calls to get_block() for write to same offset. By making such
buffers as BH_New, we also assure that sub-block zeroing of buffered
writes happens correctly.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
These struct buffer_heads are allocated on the stack (and hence are
initialized with stack garbage). They are only used to call a
get_blocks() function, so that's mostly OK, but b_state must be
initialized to be 0 so we don't have any unexpected BH_* flags set by
accident, such as BH_Unwritten or BH_Delay.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If two CPU's simultaneously call ext4_ext_get_blocks() at the same
time, there is nothing protecting the i_cached_extent structure from
being used and updated at the same time. This could potentially cause
the wrong location on disk to be read or written to, including
potentially causing the corruption of the block group descriptors
and/or inode table.
This bug has been in the ext4 code since almost the very beginning of
ext4's development. Fortunately once the data is stored in the page
cache cache, ext4_get_blocks() doesn't need to be called, so trying to
replicate this problem to the point where we could identify its root
cause was *extremely* difficult. Many thanks to Kevin Shanahan for
working over several months to be able to reproduce this easily so we
could finally nail down the cause of the corruption.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
We need to mark the buffer_head mapping preallocated space as new
during write_begin. Otherwise we don't zero out the page cache content
properly for a partial write. This will cause file corruption with
preallocation.
Now that we mark the buffer_head new we also need to have a valid
buffer_head blocknr so that unmap_underlying_metadata() unmaps the
correct block.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Fix potential inode allocation soft lockup in Orlov allocator
ext4: Make the extent validity check more paranoid
jbd: use SWRITE_SYNC_PLUG when writing synchronous revoke records
jbd2: use SWRITE_SYNC_PLUG when writing synchronous revoke records
ext4: really print the find_group_flex fallback warning only once
Instead of just checking that the extent block number is greater or
equal than s_first_data_block, make sure it it is not pointing into
the block group descriptors, since that is clearly wrong. This helps
prevent filesystem from getting very badly corrupted in case an extent
block is corrupted.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Make sure we validate extent details only when read from the disk.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds checks to validate the extent entries along with extent
headers, to avoid crashes caused by corrupt filesystems.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The find_group_flex() inode allocator is now only used if the
filesystem is mounted using the "oldalloc" mount option. It is
replaced with the original Orlov allocator that has been updated for
flex_bg filesystems (it should behave the same way if flex_bg is
disabled). The inode allocator now functions by taking into account
each flex_bg group, instead of each block group, when deciding whether
or not it's time to allocate a new directory into a fresh flex_bg.
The block allocator has also been changed so that the first block
group in each flex_bg is preferred for use for storing directory
blocks. This keeps directory blocks close together, which is good for
speeding up e2fsck since large directories are more likely to look
like this:
debugfs: stat /home/tytso/Maildir/cur
Inode: 1844562 Type: directory Mode: 0700 Flags: 0x81000
Generation: 1132745781 Version: 0x00000000:0000ad71
User: 15806 Group: 15806 Size: 1060864
File ACL: 0 Directory ACL: 0
Links: 2 Blockcount: 2072
Fragment: Address: 0 Number: 0 Size: 0
ctime: 0x499c0ff4:164961f4 -- Wed Feb 18 08:41:08 2009
atime: 0x499c0ff4:00000000 -- Wed Feb 18 08:41:08 2009
mtime: 0x49957f51:00000000 -- Fri Feb 13 09:10:25 2009
crtime: 0x499c0f57:00d51440 -- Wed Feb 18 08:38:31 2009
Size of extra inode fields: 28
BLOCKS:
(0):7348651, (1-258):7348654-7348911
TOTAL: 259
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The ext4_ext_search_right() function is confusing; it uses a
"depth" variable which is 0 at the root and maximum at the leaves,
but the on-disk metadata uses a "depth" (actually eh_depth) which
is opposite: maximum at the root, and 0 at the leaves.
The ext4_ext_check_header() function is given a depth and checks
the header agaisnt that depth; it expects the on-disk semantics,
but we are giving it the opposite in the while loop in this
function. We should be giving it the on-disk notion of "depth"
which we can get from (p_depth - depth) - and if you look, the last
(more commonly hit) call to ext4_ext_check_header() does just this.
Sending in the wrong depth results in (incorrect) messages
about corruption:
EXT4-fs error (device sdb1): ext4_ext_search_right: bad header
in inode #2621457: unexpected eh_depth - magic f30a, entries 340,
max 340(0), depth 1(2)
http://bugzilla.kernel.org/show_bug.cgi?id=12821
Reported-by: David Dindorp <ddi@dubex.dk>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When bg_free_blocks_count was renamed to bg_free_blocks_count_lo in
560671a0, its uses under EXT4FS_DEBUG were not changed to the helper
ext4_free_blks_count.
Another commit, 498e5f24, also did not change everything needed under
EXT4FS_DEBUG, thus making it spill some warnings related to printing
format.
This commit fixes both issues and makes ext4 build again when
EXT4FS_DEBUG is enabled.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (57 commits)
jbd2: Fix oops in jbd2_journal_init_inode() on corrupted fs
ext4: Remove "extents" mount option
block: Add Kconfig help which notes that ext4 needs CONFIG_LBD
ext4: Make printk's consistently prefixed with "EXT4-fs: "
ext4: Add sanity checks for the superblock before mounting the filesystem
ext4: Add mount option to set kjournald's I/O priority
jbd2: Submit writes to the journal using WRITE_SYNC
jbd2: Add pid and journal device name to the "kjournald2 starting" message
ext4: Add markers for better debuggability
ext4: Remove code to create the journal inode
ext4: provide function to release metadata pages under memory pressure
ext3: provide function to release metadata pages under memory pressure
add releasepage hooks to block devices which can be used by file systems
ext4: Fix s_dirty_blocks_counter if block allocation failed with nodelalloc
ext4: Init the complete page while building buddy cache
ext4: Don't allow new groups to be added during block allocation
ext4: mark the blocks/inode bitmap beyond end of group as used
ext4: Use new buffer_head flag to check uninit group bitmaps initialization
ext4: Fix the race between read_inode_bitmap() and ext4_new_inode()
ext4: code cleanup
...
When I review ocfs2 code, find there are 2 typos to "successfull". After
doing grep "successfull " in kernel tree, 22 typos found totally -- great
minds always think alike :)
This patch fixes all the similar typos. Thanks for Randy's ack and comments.
Signed-off-by: Coly Li <coyli@suse.de>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Vlad Yasevich <vladislav.yasevich@hp.com>
Cc: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This mount option is largely superfluous, and in fact the way it was
implemented was buggy; if a filesystem which did not have the extents
feature flag was mounted -o extents, the filesystem would attempt to
create and use extents-based file even though the extents feature flag
was not eabled. The simplest thing to do is to nuke the mount option
entirely. It's not all that useful to force the non-creation of new
extent-based files if the filesystem can support it.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* Change EXT4_HAS_*_FEATURE to return a boolean
* Add a function prototype for ext4_fiemap() in ext4.h
* Make ext4_ext_fiemap_cb() and ext4_xattr_fiemap() be static functions
* Add lock annotations to mb_free_blocks()
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Convert the unsigned longs that are most responsible for bloating the
stack usage on 64-bit systems.
Nearly all places in the ext3/4 code which uses "unsigned long" is
probably a bug, since on 32-bit systems a ulong a 32-bits, which means
we are wasting stack space on 64-bit systems.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The i_ext_generation was incremented, but never used. Remove it to
slim down the ext4_inode_info structure.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
A few weeks ago I posted a patch for discussion that allowed ext4 to run
without a journal. Since that time I've integrated the excellent
comments from Andreas and fixed several serious bugs. We're currently
running with this patch and generating some performance numbers against
both ext2 (with backported reservations code) and ext4 with and without
a journal. It just so happens that running without a journal is
slightly faster for most everything.
We did
iozone -T -t 4 s 2g -r 256k -T -I -i0 -i1 -i2
which creates 4 threads, each of which create and do reads and writes on
a 2G file, with a buffer size of 256K, using O_DIRECT for all file opens
to bypass the page cache. Results:
ext2 ext4, default ext4, no journal
initial writes 13.0 MB/s 15.4 MB/s 15.7 MB/s
rewrites 13.1 MB/s 15.6 MB/s 15.9 MB/s
reads 15.2 MB/s 16.9 MB/s 17.2 MB/s
re-reads 15.3 MB/s 16.9 MB/s 17.2 MB/s
random readers 5.6 MB/s 5.6 MB/s 5.7 MB/s
random writers 5.1 MB/s 5.3 MB/s 5.4 MB/s
So it seems that, so far, this was a useful exercise.
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The convenience function do_blk_alloc() is a static function with only
one caller, so fold it into ext4_new_meta_blocks() to simplify the
code and to make it easier to understand.
To save more stack space, if count is a null pointer in
ext4_new_meta_blocks() assume that caller wanted a single block (and
if there is an error, no blocks were allocated).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
There were only two one callers of the function ext4_new_meta_block(),
which just a very simpler wrapper function around
ext4_new_meta_blocks(). Change those two functions to call
ext4_new_meta_blocks() directly, to save code and stack space usage.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_ext_walk_space() was reinstated to be used for iterating over file
extents with a callback; it is used by the ext4 fiemap implementation.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-ext4@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
With delayed allocation we use i_data_sem to update i_disksize. We need
to update i_disksize only if the new size specified is greater than the
current value and we need to make sure we don't race with other
i_disksize update. With delayed allocation we will switch to the
write_begin function for non-delayed allocation if we are low on free
blocks. This means the write_begin function for non-delayed allocation
also needs to use the same locking.
We also need to check and update i_disksize even if the new size is less
that inode.i_size because of delayed allocation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Previous delalloc writepages implementation started a new transaction
outside of a loop which called get_block() to do the block allocation.
Since we didn't know exactly how many blocks would need to be allocated,
the estimated journal credits required was very conservative and caused
many issues.
With the reworked delayed allocation, a new transaction is created for
each get_block(), thus we don't need to guess how many credits for the
multiple chunk of allocation. We start every transaction with enough
credits for inserting a single exent. When estimate the credits for
indirect blocks to allocate a chunk of blocks, we need to know the
number of data blocks to allocate. We use the total number of reserved
delalloc datablocks; if that is too big, for non-extent files, we need
to limit the number of blocks to EXT4_MAX_TRANS_BLOCKS.
Code cleanup from Aneesh.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Reviewed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
DIO and fallocate credit calculation is different than writepage, as
they do start a new journal right for each call to ext4_get_blocks_wrap().
This patch uses the helper function in DIO and fallocate case, passing
a flag indicating that the modified data are contigous thus could account
less indirect/index blocks.
This patch also fixed the journal credit reservation for direct I/O
(DIO). Previously the estimated credits for DIO only was calculated for
non-extent files, which was not enough if the file is extent-based.
Also fixed was fallocate double-counting credits for modifying the the
superblock.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch modified the writepage/write_begin credit calculation for
extent files, to use the credits caculation helper function.
The current calculation of how many index/leaf blocks should be
accounted is too conservetive, it always considered the worse case,
where the tree level is 5, and in the case of multiple chunk
allocations, it always assumed no blocks were dirtied in common across
the allocations. This path uses the accurate depth of the inode with
some extras to calculate the index blocks, and also less conservative in
the case of multiple allocation accounting.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_ext_truncate(), we should use the more generic
ext4_discard_reservations() call so we do the right thing when the
filesystem is mounted with the nomballoc option.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
With the FLEX_BG layout, there is no reason why extents can't cross
block groups, so make the truncate code reserve enough credits so we
don't BUG if we come across such an extent.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The ext4_ext_journal_restart() is a convenience function which checks
to see if the requested number of credits is present, and if so it
closes the current transaction and attaches the current handle to the
new transaction. Unfortunately, it wasn't proprely checking the
return value from ext4_journal_extend(), so it was starting a new
transaction when one was not necessary, and returning an error when
all that was necessary was to restart the handle with a new
transaction.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Inserting an extent can cause a new entry in the already existing index
block. That doesn't increase the depth of the instead. Instead it adds a
new leaf block. Now with the new leaf block the path information
corresponding to the logical block should be fetched from the new block.
The old path will be pointing to the old leaf block.
We need to recalucate the path information on extent insert
even if depth doesn't change. Without this change, the extent merge
after converting an unwritten extent to initialized extent takes the wrong
extent and cause data corruption.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
With the reverse locking, we need to start a transation before taking
the page lock, so in ext4_da_writepages() we need to break the write-out
into chunks, and restart the journal for each chunck to ensure the
write-out fits in a single transaction.
Updated patch from Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
which fixes delalloc sync hang with journal lock inversion, and address
the performance regression issue.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch does block reservation for delayed
allocation, to avoid ENOSPC later at page flush time.
Blocks(data and metadata) are reserved at da_write_begin()
time, the freeblocks counter is updated by then, and the number of
reserved blocks is store in per inode counter.
At the writepage time, the unused reserved meta blocks are returned
back. At unlink/truncate time, reserved blocks are properly released.
Updated fix from Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
to fix the oldallocator block reservation accounting with delalloc, added
lock to guard the counters and also fix the reservation for meta blocks.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We cannot call ext4_orphan_add() from under i_data_sem because that
causes a lock ordering violation between i_data_sem and and the
superblock lock.
Updated with Aneesh's locking order fix
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This changes are needed to support data=ordered mode handling via
inodes. This enables us to get rid of the journal heads and buffer
heads for data buffers in the ordered mode. With the changes, during
tranasaction commit we writeout the inode pages using the
writepages()/writepage(). That implies we take page lock during
transaction commit. This can cause a deadlock with the locking order
page_lock -> jbd2_journal_start, since the jbd2_journal_start can wait
for the journal_commit to happen and the journal_commit now needs to
take the page lock. To avoid this dead lock reverse the locking order.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Use the BUFFER_FNS functions (set_buffer_foo) to set buffer
head state atomically instead of nonatomic __set_bit().
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Move the code related to block allocation to a single function and add helper
funtions to differient allocation for data and meta data blocks
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When mballoc is enabled, block allocation for old block-based
files are allocated using mballoc allocator instead of old
block-based allocator. The old ext3 block reservation is turned
off when mballoc is turned on.
However, the in-core preallocation is not enabled for block-based/
non-extent based file block allocation. This result in performance
regression, as now we don't have "reservation" ore in-core preallocation
to prevent interleaved fragmentation in multiple writes workload.
This patch fix this by enable per inode in-core preallocation
for non extent files when mballoc is used.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Fix ext4_ext_journal_restart() so it returns any errors reported by
ext4_journal_extend() and ext4_journal_restart().
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When pos=0 or depth, the fields of ext4_ext_path is are not
completely filled. This patch also removes some unnecessary code.
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When allocating unitialized space at the end of file which had been
preallocated with the FALLOC_FL_KEEP_SIZE option, the file size is not
updated at that time. But the later we are not updating the file size
when writing to that preallocated space.
These changes are for code correctness. This patch allows us to update
the i_disksize at the write_end() callback of filesystem properly.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The recently announced "Linux POSIX file system test suite"
caught a truncate issue when using extents:
mtime and ctime are not updated when truncate is successful.
This is the single issue caught with "default" ext4 (mkfs and mount
with minimal options).
The testsuite does not report failure with -o noextents.
With the following patch, all tests of the testsuite pass.
Signed-off-by: Solofo Ramangalahy <Solofo.Ramangalahy@bull.net>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Move ext4 headers out of include/linux. This is just the trivial move,
there's some more thing that could be done later.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This fixes the allocations with GFP_KERNEL while under a transaction problems
in ext4. This patch is the same as its ext3 counterpart, just switches these
to GFP_NOFS.
Signed-off-by: Josef Bacik <jbacik@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When we convert an uninitialized extent to an initialized extent
we need to make sure we return the number of blocks in the
extent from the file system block corresponding to logical
file block. Otherwise we cache wrong extent details and this
results in file system corruption.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_ext_get_blocks() returns the number of blocks allocated with buffer
head unmapped for a read from prealloc space. This is needed so that
delayed allocation doesn't do block reservation for prealloc space
since the blocks are already reserved on disk. Mark the buffer head
unwritten. Some code paths try to read the block if the buffer_head is
not new and no uptodate. Marking the buffer head unwritten avoids this
reading.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_ext_get_blocks() returns number of blocks allocated with buffer
heads unmapped for a read from prealloc space. This is needed so that
delayed allocation doesn't do block reservation for prealloc space since
the blocks are already resevred on disk. Fix ext4_ext_get_blocks to not
return greater than max_blocks, since some of the code paths cannot
handle such a return value.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_fallocate needs to update file size in each transaction. Otherwise
if we crash the file size won't be seen. We were also not marking
the inode dirty after updating file size before. Also when we try to
retry allocation due to ENOSPC, make sure we reset the variable ret so
that we actually do a retry.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the preallocated area is small zero out the full extent
instead of splitting them. This should avoid the "write
every alternate block" problem that could grow the number
of extents dramatically.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch handles possible ENOSPC errors when writing to an
uninitialized extent in case the filesystem is full.
A write to a prealloc area causes the split of an unititalized extent
into initialized and uninitialized extents. If we don't have
space to add new extent information, instead of returning error,
convert the existing uninitialized extent to initialized one. We
need to zero out the blocks corresponding to the entire extent to
prevent uninitialized data reaching userspace.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Put the old extent details back if we fail to split the
uninitialized extent.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If we fail to allocate blocks don't call ext4_error. Also don't hide
errors from ext4_get_blocks_wrap
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch fixes a bug when writing to preallocated but uninitialized
blocks, which resulted in a BUG in fs/buffer.c saying that the buffer
is not mapped.
When writing to a file, ext4_get_block_wrap() is called with create=1 in
order to request that blocks be allocated if necessary. It currently
calls ext4_get_blocks() with create=0 in order to do a lookup first. If
the inode contains an unitialized data block, the buffer head is left
unampped, which ext4_get_blocks_wrap() returns, causing the BUG.
We fix this by checking to see if the buffer head is unmapped, and if
so, we make sure the the buffer head is mapped by calling
ext4_ext_get_blocks with create=1.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When a directory inode is allocated in the last group and the last group
contains less than s_blocks_per_group blocks, the initial block allocated
for the directory is not always allocated in the same group as the
directory inode, but in one of the first groups of the filesystem (group 1
for example).
Depending on the current process's pid, ext4_find_near() and
ext4_ext_find_goal() can return a block number greater than the maximum
blocks count in the filesystem and in that case the block will be not
allocated in the same group as the inode.
The following patch fixes the problem.
Should the modification also be done in ext2/3 code?
Signed-off-by: Valerie Clement <valerie.clement@bull.net>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When the user was writing into an unitialized extent,
ext4_ext_convert_to_initialize() was not requesting journal write access
before it started to modify the extent tree. Fix this oversight.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The path variable returned via ext4_ext_find_extent is a kmalloc
variable and needs to be freeded. It also contains a reference to
buffer_head which needs to be dropped.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_fallocate() was trying to acquire i_data_sem outside of
jbd2_start_transaction/jbd2_journal_stop, which violates ext4's locking
hierarchy. So we take i_mutex to prevent writes and truncates during
the complete fallocate operation, and use ext4_get_block_wrap() which
acquires and releases i_data_sem for each block allocation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4 uses the high bit of the extent length to encode whether the extent
is intialized or not. The helper function ext4_ext_get_actual_len should
be used to get the actual length of the extent.
This addresses the kernel bug documented here:
http://bugzilla.kernel.org/show_bug.cgi?id=9732
kernel BUG at fs/ext4/extents.c:1056!
....
Call Trace:
[<ffffffff88366073>] :ext4dev:ext4_ext_get_blocks+0x5ba/0x8c1
[<ffffffff81053c91>] lock_release_holdtime+0x27/0x49
[<ffffffff812748f6>] _spin_unlock+0x17/0x20
[<ffffffff883400a6>] :jbd2:start_this_handle+0x4e0/0x4fe
[<ffffffff88366564>] :ext4dev:ext4_fallocate+0x175/0x39a
[<ffffffff81053c91>] lock_release_holdtime+0x27/0x49
[<ffffffff81056480>] __lock_acquire+0x4e7/0xc4d
[<ffffffff81053c91>] lock_release_holdtime+0x27/0x49
[<ffffffff810a8de7>] sys_fallocate+0xe4/0x10d
[<ffffffff8100c043>] tracesys+0xd5/0xda
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Fix bug reported by Dmitry Monakhov caused by lost error code
Testcase:
blksize = 0x1000;
fd = open(argv[1], O_RDWR|O_CREAT, 0700);
unsigned long long sz = 0x10000000UL;
/* allocating big blocks chunk */
syscall(__NR_fallocate, fd, 0, 0UL, sz)
/* grab all other available filesystem space */
tfd = open("tmp", O_RDWR|O_CREAT|O_DIRECT, 0700);
while( write(tfd, buf, 4096) > 0); /* loop untill ENOSPC */
fsync(fd); /* just in case */
while (pos < sz) {
/* each seek+ write operation result in splits uninitialized extent
in three extents. Splitting may result in new extent allocation
which probably will fail because of ENOSPC*/
lseek(fd, blksize*2 -1, SEEK_CUR);
if ((ret = write(fd, 'a', 1)) != 1)
exit(1);
pos += blksize * 2;
}
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add the functions ext4_ext_search_left() and ext4_ext_search_right(),
which are used by mballoc during ext4_ext_get_blocks to decided whether
to merge extent information.
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Johann Lombardi <johann@clusterfs.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We are currently taking the truncate_mutex for every read. This would have
performance impact on large CPU configuration. Convert the lock to read write
semaphore and take read lock when we are trying to read the file.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
When doing a migrate from ext3 to ext4 inode we need to make sure the test
for inode type and walking inode data happens inside lock. To make this
happen move truncate_mutex early before checking the i_flags.
This actually should enable us to remove the verify_chain().
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
There are many casts in extents.c which are not needed,
as the variables are already the type of the cast, or
are being promoted for no particular reason in printk's.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
This patch adds a new data type ext4_lblk_t to represent
the logical file blocks.
This is the preparatory patch to support large files in ext4
The follow up patch with convert the ext4_inode i_blocks to
represent the number of blocks in file system block size. This
changes makes it possible to have a block number 2**32 -1 which
will result in overflow if the block number is represented by
signed long. This patch convert all the block number to type
ext4_lblk_t which is typedef to __u32
Also remove dead code ext4_ext_walk_space
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Convert ext4_extent_idx.ei_leaf ext4_extent_idx.ei_leaf_lo
This helps in finding BUGs due to direct partial access of
these split 48 bit values.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Convert ext4_extent.ee_start to ext4_extent.ee_start_lo
This helps in finding BUGs due to direct partial access of
these split 48 bit values
Also fix direct partial access in ext4 code
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Yan Zheng wrote:
> I think I found a bug in ext4/extents.c, "ext4_ext_put_in_cache" uses
> "__u32" to receive physical block number. "ext4_ext_put_in_cache" is
> used in "ext4_ext_get_blocks", it sets ext4 inode's extent cache
> according most recently tree lookup (higher 16 bits of saved physical
> block number are always zero). when serving a mapping request,
> "ext4_ext_get_blocks" first check whether the logical block is in
> inode's extent cache. if the logical block is in the cache and the
> cached region isn't a gap, "ext4_ext_get_blocks" gets physical block
> number by using cached region's physical block number and offset in
> the cached region. as described above, "ext4_ext_get_blocks" may
> return wrong result when there are physical block numbers bigger than
> 0xffffffff.
>
You are right. Thanks for reporting this!
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Cc: Yan Zheng <yanzheng@21cn.com>
Cc: <stable@kernel.org>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the EXT_LAST_INDEX macro; that's what it's there for.
Clean up ext4_ext_ext_grow_indepth() so the correct EXT_FIRST_INDEX or
EXT_FIRST_MACRO is used as necessary. The two macros are equivalent, so
the C will collapse the if statement out, but it makes the code much
more readable.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Acked-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Singed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add more run-time checking of extent header fields and remove BUG_ON
checks so we don't panic the kernel just because the on-disk filesystem
is corrupted.
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This change was suggested by Andreas Dilger.
This patch changes the EXT_MAX_LEN value and extent code which marks/checks
uninitialized extents. With this change it will be possible to have
initialized extents with 2^15 blocks (earlier the max blocks we could have
was 2^15 - 1). This way we can have better extent-to-block alignment.
Now, maximum number of blocks we can have in an initialized extent is 2^15
and in an uninitialized extent is 2^15 - 1.
Signed-off-by: Amit Arora <aarora@in.ibm.com>
This patch adds write support to the uninitialized extents that get
created when a preallocation is done using fallocate(). It takes care of
splitting the extents into multiple (upto three) extents and merging the
new split extents with neighbouring ones, if possible.
Signed-off-by: Amit Arora <aarora@in.ibm.com>
This patch implements ->fallocate() inode operation in ext4. With this
patch users of ext4 file systems will be able to use fallocate() system
call for persistent preallocation. Current implementation only supports
preallocation for regular files (directories not supported as of date)
with extent maps. This patch does not support block-mapped files currently.
Only FALLOC_ALLOCATE and FALLOC_RESV_SPACE modes are being supported as of
now.
Signed-off-by: Amit Arora <aarora@in.ibm.com>
we should free just the allocated blocks.
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds a check for overlap of extents and cuts short the
new extent to be inserted, if there is a chance of overlap.
Signed-off-by: Amit Arora <aarora@in.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the various misspellings of "agressive", as well as a couple
other things on the same lines while we're there.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Removes all inline keywords, since the compiler will make static functions
inline when it is appropriate.
Signed-off-by: Avantika Mathur <mathur@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix a nit in ext4_ext_calc_credits_for_insert(). Besides, credits for the
new root are already added in the index split accounting.
Signed-off-by: Johann Lombardi <johann.lombardi@bull.net>
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The Coverity checker noted that this was dead code, since in all places
above in this function, "err" is immediately checked.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Someone's tab key is emitting spaces. Attempt to repair some of the damage.
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Previously when in-kernel ext4 block type is sector_t, it's only 4 bits long
under some 32bit arch (when CONFIG_LBD is not on). So we need to check the
size of sector_t before we read 48bit long on-disk blocks to in-kernel blocks.
These checks are unnecessary now as we changed the in-kernel blocks to
unsigned longlong.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change ext4 in-kernel block type (ext4_fsblk_t) from sector_t to unsigned
long long. Remove ext4 block type string micro E3FSBLK, replaced with "%llu"
[akpm@osdl.org: build fix]
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make it possible to add file preallocation support in future as an RO_COMPAT
feature by recognizing uninitialized extents as holes and limiting extent
length to keep the top bit of ee_len free for marking uninitialized extents.
Signed-off-by: Suparna Bhattacharya <suparna@in.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On disk extents format:
/*
* this is extent on-disk structure
* it's used at the bottom of the tree
*/
struct ext3_extent {
__le32 ee_block; /* first logical block extent covers */
__le16 ee_len; /* number of blocks covered by extent */
__le16 ee_start_hi; /* high 16 bits of physical block */
__le32 ee_start; /* low 32 bigs of physical block */
};
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
