Commit Graph

414687 Commits

Author SHA1 Message Date
Filipe David Borba Manana
a2aa75e18a Btrfs: fix data corruption when reading/updating compressed extents
When using a mix of compressed file extents and prealloc extents, it
is possible to fill a page of a file with random, garbage data from
some unrelated previous use of the page, instead of a sequence of zeroes.

A simple sequence of steps to get into such case, taken from the test
case I made for xfstests, is:

   _scratch_mkfs
   _scratch_mount "-o compress-force=lzo"
   $XFS_IO_PROG -f -c "pwrite -S 0x06 -b 18670 266978 18670" $SCRATCH_MNT/foobar
   $XFS_IO_PROG -c "falloc 26450 665194" $SCRATCH_MNT/foobar
   $XFS_IO_PROG -c "truncate 542872" $SCRATCH_MNT/foobar
   $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foobar

This results in the following file items in the fs tree:

   item 4 key (257 INODE_ITEM 0) itemoff 15879 itemsize 160
       inode generation 6 transid 6 size 542872 block group 0 mode 100600
   item 5 key (257 INODE_REF 256) itemoff 15863 itemsize 16
       inode ref index 2 namelen 6 name: foobar
   item 6 key (257 EXTENT_DATA 0) itemoff 15810 itemsize 53
       extent data disk byte 0 nr 0 gen 6
       extent data offset 0 nr 24576 ram 266240
       extent compression 0
   item 7 key (257 EXTENT_DATA 24576) itemoff 15757 itemsize 53
       prealloc data disk byte 12849152 nr 241664 gen 6
       prealloc data offset 0 nr 241664
   item 8 key (257 EXTENT_DATA 266240) itemoff 15704 itemsize 53
       extent data disk byte 12845056 nr 4096 gen 6
       extent data offset 0 nr 20480 ram 20480
       extent compression 2
   item 9 key (257 EXTENT_DATA 286720) itemoff 15651 itemsize 53
       prealloc data disk byte 13090816 nr 405504 gen 6
       prealloc data offset 0 nr 258048

The on disk extent at offset 266240 (which corresponds to 1 single disk block),
contains 5 compressed chunks of file data. Each of the first 4 compress 4096
bytes of file data, while the last one only compresses 3024 bytes of file data.
Therefore a read into the file region [285648 ; 286720[ (length = 4096 - 3024 =
1072 bytes) should always return zeroes (our next extent is a prealloc one).

The solution here is the compression code path to zero the remaining (untouched)
bytes of the last page it uncompressed data into, as the information about how
much space the file data consumes in the last page is not known in the upper layer
fs/btrfs/extent_io.c:__do_readpage(). In __do_readpage we were correctly zeroing
the remainder of the page but only if it corresponds to the last page of the inode
and if the inode's size is not a multiple of the page size.

This would cause not only returning random data on reads, but also permanently
storing random data when updating parts of the region that should be zeroed.
For the example above, it means updating a single byte in the region [285648 ; 286720[
would store that byte correctly but also store random data on disk.

A test case for xfstests follows soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
Josef Bacik
27a377db74 Btrfs: don't loop forever if we can't run because of the tree mod log
A user reported a 100% cpu hang with my new delayed ref code.  Turns out I
forgot to increase the count check when we can't run a delayed ref because of
the tree mod log.  If we can't run any delayed refs during this there is no
point in continuing to look, and we need to break out.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
David Sterba
8051aa1a3d btrfs: reserve no transaction units in btrfs_ioctl_set_features
Added in patch "btrfs: add ioctls to query/change feature bits online"
modifications to superblock don't need to reserve metadata blocks when
starting a transaction.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
Jeff Mahoney
d0270aca88 btrfs: commit transaction after setting label and features
The set_fslabel ioctl uses btrfs_end_transaction, which means it's
possible that the change will be lost if the system crashes, same for
the newly set features. Let's use btrfs_commit_transaction instead.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
Josef Bacik
6cc98d90f8 Btrfs: fix assert screwup for the pending move stuff
Wang noticed that he was failing btrfs/030 even though me and Filipe couldn't
reproduce.  Turns out this is because Wang didn't have CONFIG_BTRFS_ASSERT set,
which meant that a key part of Filipe's original patch was not being built in.
This appears to be a mess up with merging Filipe's patch as it does not exist in
his original patch.  Fix this by changing how we make sure del_waiting_dir_move
asserts that it did not error and take the function out of the ifdef check.
This makes btrfs/030 pass with the assert on or off.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
Filipe David Borba Manana
60efa5eb2e Btrfs: use late_initcall instead of module_init
It seems that when init_btrfs_fs() is called, crc32c/crc32c-intel might
not always be already initialized, which results in the call to crypto_alloc_shash()
returning -ENOENT, as experienced by Ahmet who reported this.

Therefore make sure init_btrfs_fs() is called after crc32c is initialized (which
is at initialization level 6, module_init), by using late_initcall (which is at
initialization level 7) instead of module_init for btrfs.

Reported-and-Tested-by: Ahmet Inan <ainan@mathematik.uni-freiburg.de>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-03 09:01:28 -08:00
Filipe David Borba Manana
0b947aff15 Btrfs: use btrfs_crc32c everywhere instead of libcrc32c
After the commit titled "Btrfs: fix btrfs boot when compiled as built-in",
LIBCRC32C requirement was removed from btrfs' Kconfig. This made it not
possible to build a kernel with btrfs enabled (either as module or built-in)
if libcrc32c is not enabled as well. So just replace all uses of libcrc32c
with the equivalent function in btrfs hash.h - btrfs_crc32c.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-03 09:01:27 -08:00
Josef Bacik
8101c8dbf6 Btrfs: disable snapshot aware defrag for now
It's just broken and it's taking a lot of effort to fix it, so for now just
disable it so people can defrag in peace.  Thanks,

Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-03 09:01:27 -08:00
Chris Mason
cf93da7bcf Btrfs: fix spin_unlock in check_ref_cleanup
Our goto out should have gone a little farther.

Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:31 -08:00
Chris Mason
90d3e592e9 Btrfs: setup inode location during btrfs_init_inode_locked
We have a race during inode init because the BTRFS_I(inode)->location is setup
after the inode hash table lock is dropped.  btrfs_find_actor uses the location
field, so our search might not find an existing inode in the hash table if we
race with the inode init code.

This commit changes things to setup the location field sooner.  Also the find actor now
uses only the location objectid to match inodes.  For inode hashing, we just
need a unique and stable test, it doesn't have to reflect the inode numbers we
show to userland.

Signed-off-by: Chris Mason <clm@fb.com>
CC: stable@vger.kernel.org
2014-01-29 07:06:30 -08:00
Chris Mason
514ac8ad87 Btrfs: don't use ram_bytes for uncompressed inline items
If we truncate an uncompressed inline item, ram_bytes isn't updated to reflect
the new size.  The fixe uses the size directly from the item header when
reading uncompressed inlines, and also fixes truncate to update the
size as it goes.

Reported-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
CC: stable@vger.kernel.org
2014-01-29 07:06:29 -08:00
Filipe David Borba Manana
23c6bf6a91 Btrfs: fix btrfs_search_slot_for_read backwards iteration
If the current path's leaf slot is 0, we do search for the previous
leaf (via btrfs_prev_leaf) and set the new path's leaf slot to a
value corresponding to the number of items - 1 of the former leaf.
Fix this by using the slot set by btrfs_prev_leaf, decrementing it
by 1 if it's equal to the leaf's number of items.

Use of btrfs_search_slot_for_read() for backward iteration is used in
particular by the send feature, which could miss items when the input
leaf has less items than its previous leaf.

This could be reproduced by running btrfs/007 from xfstests in a loop.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:28 -08:00
Wang Shilong
49fc647a2c Btrfs: do not export ulist functions
There are not any users that use ulist except Btrfs,don't
export them.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:27 -08:00
Wang Shilong
4c7a6f74ce Btrfs: rework ulist with list+rb_tree
We are really suffering from now ulist's implementation, some developers
gave their try, and i just gave some of my ideas for things:

 1. use list+rb_tree instead of arrary+rb_tree

 2. add cur_list to iterator rather than ulist structure.

 3. add seqnum into every node when they are added, this is
 used to do selfcheck when iterating node.

I noticed Zach Brown's comments before, long term is to kick off
ulist implementation, however, for now, we need at least avoid
arrary from ulist.

Cc: Liu Bo <bo.li.liu@oracle.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Zach Brown <zab@redhat.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:27 -08:00
Wang Shilong
f05c474688 Btrfs: fix memory leaks on walking backrefs failure
When walking backrefs, we may iterate every inode's extent
and add/merge them into ulist, and the caller will free memory
from ulist.

However, if we fail to allocate inode's extents element
memory or ulist_add() fail to allocate memory, we won't
add allocated memory into ulist, and the caller won't
free some allocated memory thus memory leaks happen.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:26 -08:00
Filipe David Borba Manana
bf54f412f0 Btrfs: fix send file hole detection leading to data corruption
There was a case where file hole detection was incorrect and it would
cause an incremental send to override a section of a file with zeroes.

This happened in the case where between the last leaf we processed which
contained a file extent item for our current inode and the leaf we're
currently are at (and has a file extent item for our current inode) there
are only leafs containing exclusively file extent items for our current
inode, and none of them was updated since the previous send operation.
The file hole detection code would incorrectly consider the file range
covered by these leafs as a hole.

A test case for xfstests follows soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:25 -08:00
Wang Shilong
bca1a29003 Btrfs: add a reschedule point in btrfs_find_all_roots()
I can easily trigger the following warnings when enabling quota
in my virtual machine(running Opensuse), Steps are firstly creating
a subvolume full of fragment extents, and then create many snapshots
(500 in my test case).

[ 2362.808459] BUG: soft lockup - CPU#0 stuck for 22s! [btrfs-qgroup-re:1970]

[ 2362.809023] task: e4af8450 ti: e371c000 task.ti: e371c000
[ 2362.809026] EIP: 0060:[<fa38f4ae>] EFLAGS: 00000246 CPU: 0
[ 2362.809049] EIP is at __merge_refs+0x5e/0x100 [btrfs]
[ 2362.809051] EAX: 00000000 EBX: cfadbcf0 ECX: 00000000 EDX: cfadbcb0
[ 2362.809052] ESI: dd8d3370 EDI: e371dde0 EBP: e371dd6c ESP: e371dd5c
[ 2362.809054]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[ 2362.809055] CR0: 80050033 CR2: ac454d50 CR3: 009a9000 CR4: 001407d0
[ 2362.809099] Stack:
[ 2362.809100]  00000001 e371dde0 dfcc6890 f29f8000 e371de28 fa39016d 00000011 00000001
[ 2362.809105]  99bfc000 00000000 93928000 00000000 00000001 00000050 e371dda8 00000001
[ 2362.809109]  f3a31000 f3413000 00000001 e371ddb8 000040a8 00000202 00000000 00000023
[ 2362.809113] Call Trace:
[ 2362.809136]  [<fa39016d>] find_parent_nodes+0x34d/0x1280 [btrfs]
[ 2362.809156]  [<fa391172>] btrfs_find_all_roots+0xb2/0x110 [btrfs]
[ 2362.809174]  [<fa3934a8>] btrfs_qgroup_rescan_worker+0x358/0x7a0 [btrfs]
[ 2362.809180]  [<c024d0ce>] ? lock_timer_base.isra.39+0x1e/0x40
[ 2362.809199]  [<fa3648df>] worker_loop+0xff/0x470 [btrfs]
[ 2362.809204]  [<c027a88a>] ? __wake_up_locked+0x1a/0x20
[ 2362.809221]  [<fa3647e0>] ? btrfs_queue_worker+0x2b0/0x2b0 [btrfs]
[ 2362.809225]  [<c025ebbc>] kthread+0x9c/0xb0
[ 2362.809229]  [<c06b487b>] ret_from_kernel_thread+0x1b/0x30
[ 2362.809233]  [<c025eb20>] ? kthread_create_on_node+0x110/0x110

By adding a reschedule point at the end of btrfs_find_all_roots(), i no longer
hit these warnings.

Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:25 -08:00
Filipe David Borba Manana
7fdd29d02e Btrfs: make send's file extent item search more efficient
Instead of looking for a file extent item, process it, release the path
and do a btree search for the next file extent item, just process all
file extent items in a leaf without intermediate btree searches. This way
we save cpu and we're not blocking other tasks or affecting concurrency on
the btree, because send's paths use the commit root and skip btree node/leaf
locking.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:24 -08:00
Wang Shilong
95def2ede1 Btrfs: fix to catch all errors when resolving indirect ref
We can only tolerate ENOENT here, for other errors, we should
return directly.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:23 -08:00
Wang Shilong
538f72cdf0 Btrfs: fix protection between walking backrefs and root deletion
There is a race condition between resolving indirect ref and root deletion,
and we should gurantee that root can not be destroyed to avoid accessing
broken tree here.

Here we fix it by holding @subvol_srcu, and we will release it as soon
as we have held root node lock.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:23 -08:00
Gui Hecheng
3c9665df0c btrfs: fix warning while merging two adjacent extents
When we have two adjacent extents in relink_extent_backref,
we try to merge them. When we use btrfs_search_slot to locate the
slot for the current extent, we shouldn't set "ins_len = 1",
because we will merge it into the previous extent rather than
insert a new item. Otherwise, we may happen to create a new leaf
in btrfs_search_slot and path->slot[0] will be 0. Then we try to
fetch the previous item using "path->slots[0]--", and it will cause
a warning as follows:

	[  145.713385] WARNING: CPU: 3 PID: 1796 at fs/btrfs/extent_io.c:5043 map_private_extent_buffer+0xd4/0xe0
	[  145.713387] btrfs bad mapping eb start 5337088 len 4096, wanted 167772306 8
	...
	[  145.713462]  [<ffffffffa034b1f4>] map_private_extent_buffer+0xd4/0xe0
	[  145.713476]  [<ffffffffa030097a>] ? btrfs_free_path+0x2a/0x40
	[  145.713485]  [<ffffffffa0340864>] btrfs_get_token_64+0x64/0xf0
	[  145.713498]  [<ffffffffa033472c>] relink_extent_backref+0x41c/0x820
	[  145.713508]  [<ffffffffa0334d69>] btrfs_finish_ordered_io+0x239/0xa80

I encounter this warning when running defrag having mkfs.btrfs
with option -M. At the same time there are read/writes & snapshots
running at background.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:22 -08:00
Filipe David Borba Manana
9f03740a95 Btrfs: fix infinite path build loops in incremental send
The send operation processes inodes by their ascending number, and assumes
that any rename/move operation can be successfully performed (sent to the
caller) once all previous inodes (those with a smaller inode number than the
one we're currently processing) were processed.

This is not true when an incremental send had to process an hierarchical change
between 2 snapshots where the parent-children relationship between directory
inodes was reversed - that is, parents became children and children became
parents. This situation made the path building code go into an infinite loop,
which kept allocating more and more memory that eventually lead to a krealloc
warning being displayed in dmesg:

  WARNING: CPU: 1 PID: 5705 at mm/page_alloc.c:2477 __alloc_pages_nodemask+0x365/0xad0()
  Modules linked in: btrfs raid6_pq xor pci_stub vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) snd_hda_codec_hdmi snd_hda_codec_realtek joydev radeon snd_hda_intel snd_hda_codec snd_hwdep snd_seq_midi snd_pcm psmouse i915 snd_rawmidi serio_raw snd_seq_midi_event lpc_ich snd_seq snd_timer ttm snd_seq_device rfcomm drm_kms_helper parport_pc bnep bluetooth drm ppdev snd soundcore i2c_algo_bit snd_page_alloc binfmt_misc video lp parport r8169 mii hid_generic usbhid hid
  CPU: 1 PID: 5705 Comm: btrfs Tainted: G           O 3.13.0-rc7-fdm-btrfs-next-18+ #3
  Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z77 Pro4, BIOS P1.50 09/04/2012
  [ 5381.660441]  00000000000009ad ffff8806f6f2f4e8 ffffffff81777434 0000000000000007
  [ 5381.660447]  0000000000000000 ffff8806f6f2f528 ffffffff8104a9ec ffff8807038f36f0
  [ 5381.660452]  0000000000000000 0000000000000206 ffff8807038f2490 ffff8807038f36f0
  [ 5381.660457] Call Trace:
  [ 5381.660464]  [<ffffffff81777434>] dump_stack+0x4e/0x68
  [ 5381.660471]  [<ffffffff8104a9ec>] warn_slowpath_common+0x8c/0xc0
  [ 5381.660476]  [<ffffffff8104aa3a>] warn_slowpath_null+0x1a/0x20
  [ 5381.660480]  [<ffffffff81144995>] __alloc_pages_nodemask+0x365/0xad0
  [ 5381.660487]  [<ffffffff8108313f>] ? local_clock+0x4f/0x60
  [ 5381.660491]  [<ffffffff811430e8>] ? free_one_page+0x98/0x440
  [ 5381.660495]  [<ffffffff8108313f>] ? local_clock+0x4f/0x60
  [ 5381.660502]  [<ffffffff8113fae4>] ? __get_free_pages+0x14/0x50
  [ 5381.660508]  [<ffffffff81095fb8>] ? trace_hardirqs_off_caller+0x28/0xd0
  [ 5381.660515]  [<ffffffff81183caf>] alloc_pages_current+0x10f/0x1f0
  [ 5381.660520]  [<ffffffff8113fae4>] ? __get_free_pages+0x14/0x50
  [ 5381.660524]  [<ffffffff8113fae4>] __get_free_pages+0x14/0x50
  [ 5381.660530]  [<ffffffff8115dace>] kmalloc_order_trace+0x3e/0x100
  [ 5381.660536]  [<ffffffff81191ea0>] __kmalloc_track_caller+0x220/0x230
  [ 5381.660560]  [<ffffffffa0729fdb>] ? fs_path_ensure_buf.part.12+0x6b/0x200 [btrfs]
  [ 5381.660564]  [<ffffffff8178085c>] ? retint_restore_args+0xe/0xe
  [ 5381.660569]  [<ffffffff811580ef>] krealloc+0x6f/0xb0
  [ 5381.660586]  [<ffffffffa0729fdb>] fs_path_ensure_buf.part.12+0x6b/0x200 [btrfs]
  [ 5381.660601]  [<ffffffffa072a208>] fs_path_prepare_for_add+0x98/0xb0 [btrfs]
  [ 5381.660615]  [<ffffffffa072a2bc>] fs_path_add_path+0x2c/0x60 [btrfs]
  [ 5381.660628]  [<ffffffffa072c55c>] get_cur_path+0x7c/0x1c0 [btrfs]

Even without this loop, the incremental send couldn't succeed, because it would attempt
to send a rename/move operation for the lower inode before the highest inode number was
renamed/move. This issue is easy to trigger with the following steps:

  $ mkfs.btrfs -f /dev/sdb3
  $ mount /dev/sdb3 /mnt/btrfs
  $ mkdir -p /mnt/btrfs/a/b/c/d
  $ mkdir /mnt/btrfs/a/b/c2
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap1
  $ mv /mnt/btrfs/a/b/c/d /mnt/btrfs/a/b/c2/d2
  $ mv /mnt/btrfs/a/b/c /mnt/btrfs/a/b/c2/d2/cc
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap2
  $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 > /tmp/incremental.send

The structure of the filesystem when the first snapshot is taken is:

	 .                       (ino 256)
	 |-- a                   (ino 257)
	     |-- b               (ino 258)
	         |-- c           (ino 259)
	         |   |-- d       (ino 260)
                 |
	         |-- c2          (ino 261)

And its structure when the second snapshot is taken is:

	 .                       (ino 256)
	 |-- a                   (ino 257)
	     |-- b               (ino 258)
	         |-- c2          (ino 261)
	             |-- d2      (ino 260)
	                 |-- cc  (ino 259)

Before the move/rename operation is performed for the inode 259, the
move/rename for inode 260 must be performed, since 259 is now a child
of 260.

A test case for xfstests, with a more complex scenario, will follow soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:22 -08:00
Anand Jain
2365dd3ca0 btrfs: undo sysfs when open_ctree() fails
reproducer:
mkfs.btrfs -f /dev/sdb &&\
mount /dev/sdb /btrfs &&\
btrfs dev add -f /dev/sdc /btrfs &&\
umount /btrfs &&\
wipefs -a /dev/sdc &&\
mount -o degraded /dev/sdb /btrfs
//above mount fails so try with RO
mount -o degraded,ro /dev/sdb /btrfs

------
sysfs: cannot create duplicate filename '/fs/btrfs/3f48c79e-5ed0-4e87-b189-86e749e503f4'
::

dump_stack+0x49/0x5e
warn_slowpath_common+0x87/0xb0
warn_slowpath_fmt+0x41/0x50
strlcat+0x69/0x80
sysfs_warn_dup+0x87/0xa0
sysfs_add_one+0x40/0x50
create_dir+0x76/0xc0
sysfs_create_dir_ns+0x7a/0xc0
kobject_add_internal+0xad/0x220
kobject_add_varg+0x38/0x60
kobject_init_and_add+0x53/0x70
mutex_lock+0x11/0x40
__free_pages+0x25/0x30
free_pages+0x41/0x50
selinux_sb_copy_data+0x14e/0x1e0
mount_fs+0x3e/0x1a0
vfs_kern_mount+0x71/0x120
do_mount+0x3f7/0x980
SyS_mount+0x8b/0xe0
system_call_fastpath+0x16/0x1b
------

further 'modprobe -r btrfs' fails as well

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:44 -08:00
Filipe David Borba Manana
f74b86d855 Btrfs: fix snprintf usage by send's gen_unique_name
The buffer size argument passed to snprintf must account for the
trailing null byte added by snprintf, and it returns a value >= then
sizeof(buffer) when the string can't fit in the buffer.

Since our buffer has a size of 64 characters, and the maximum orphan
name we can generate is 63 characters wide, we must pass 64 as the
buffer size to snprintf, and not 63.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:43 -08:00
Justin Maggard
c41570c9d2 btrfs: fix defrag 32-bit integer overflow
When defragging a very large file, the cluster variable can wrap its 32-bit
signed int type and become negative, which eventually gets passed to
btrfs_force_ra() as a very large unsigned long value.  On 32-bit platforms,
this eventually results in an Oops from the SLAB allocator.

Change the cluster and max_cluster signed int variables to unsigned long to
match the readahead functions.  This also allows the min() comparison in
btrfs_defrag_file() to work as intended.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:43 -08:00
David Sterba
c736c095de btrfs: sysfs: list the NO_HOLES feature
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:42 -08:00
David Sterba
66b4bbd4f5 btrfs: sysfs: don't show reserved incompat feature
The COMPRESS_LZOv2 incompat featue is currently not implemented, the bit
is only reserved, no point to list it in sysfs.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:41 -08:00
David Sterba
bd60ea0fe9 btrfs: call permission checks earlier in ioctls and return EPERM
The owner and capability checks in IOC_SUBVOL_SETFLAGS and
SET_RECEIVED_SUBVOL should be called before any other checks are done.

Also unify the error code to EPERM.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:41 -08:00
David Sterba
d024206133 btrfs: restrict snapshotting to own subvolumes
Currently, any user can snapshot any subvolume if the path is accessible and
thus indirectly create and keep files he does not own under his direcotries.
This is not possible with traditional directories.

In security context, a user can snapshot root filesystem and pin any
potentially buggy binaries, even if the updates are applied.

All the snapshots are visible to the administrator, so it's possible to
verify if there are suspicious snapshots.

Another more practical problem is that any user can pin the space used
by eg. root and cause ENOSPC.

Original report:
https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/484786

CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:40 -08:00
Miao Xie
89d4346a36 Btrfs: fix wrong block group in trace during the free space allocation
We allocate the free space from the former block group, not the current
one, so should use the former one to output the trace information.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:40 -08:00
Miao Xie
215a63d139 Btrfs: cleanup the code of used_block_group in find_free_extent()
used_block_group is just used for the space cluster which doesn't
belong to the current block group, the other place needn't use it.
Or the logic of code seems unclear.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:39 -08:00
Miao Xie
920e4a58d2 Btrfs: cleanup the redundant code for the block group allocation and init
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:38 -08:00
Miao Xie
26b47ff65b Btrfs: change the members' order of btrfs_space_info structure to reduce the cache miss
It is better that the position of the lock is close to the data which is
protected by it, because they may be in the same cache line, we will load
less cache lines when we access them. So we rearrange the members' position
of btrfs_space_info structure to make the lock be closer to the its data.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:38 -08:00
Wang Shilong
ffcfaf8179 Btrfs: fix wrong search path initialization before searching tree root
To search tree root without transaction protection, we should neither search commit
root nor skip locking here, fix it.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:37 -08:00
Miao Xie
23c671a588 Btrfs: flush the dirty pages of the ordered extent aggressively during logging csum
The performance of fsync dropped down suddenly sometimes, the main reason
of this problem was that we might only flush part dirty pages in a ordered
extent, then got that ordered extent, wait for the csum calcucation. But if
no task flushed the left part, we would wait until the flusher flushed them,
sometimes we need wait for several seconds, it made the performance drop
down suddenly. (On my box, it drop down from 56MB/s to 4-10MB/s)

This patch improves the above problem by flushing left dirty pages aggressively.

Test Environment:
CPU:		2CPU * 2Cores
Memory:		4GB
Partition:	20GB(HDD)

Test Command:
 # sysbench --num-threads=8 --test=fileio --file-num=1 \
 > --file-total-size=8G --file-block-size=32768 \
 > --file-io-mode=sync --file-fsync-freq=100 \
 > --file-fsync-end=no --max-requests=10000 \
 > --file-test-mode=rndwr run

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:37 -08:00
Wang Shilong
2c21b4d733 Btrfs: fix transaction abortion when remounting btrfs from RW to RO
Steps to reproduce:
 # mkfs.btrfs -f /dev/sda8
 # mount /dev/sda8 /mnt -o flushoncommit
 # dd if=/dev/zero of=/mnt/data bs=4k count=102400 &
 # mount /dev/sda8 /mnt -o remount, ro

When remounting RW to RO, the logic is to firstly set flag
to RO and then commit transaction, however with option
flushoncommit enabled,we will do RO check within committing
transaction, so we get a transaction abortion here.

Actually,here check is wrong, we should check if FS_STATE_ERROR
is set, fix it.

Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Suggested-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:36 -08:00
Filipe David Borba Manana
e4355f34ef Btrfs: faster file extent item search in clone ioctl
When we are looking for file extent items that intersect the cloning
range, for each one that falls completely outside the range, don't
release the path and do another full tree search - just move on
to the next slot and copy the file extent item into our buffer only
if the item intersects the cloning range.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:35 -08:00
Liu Bo
1a4319cc3c Btrfs: fix extent state leak on transaction abortion
When transaction is aborted, we fail to commit transaction, instead we do
cleanup work.  After that when we umount btrfs, we get to free fs roots' log
trees respectively, but that happens after we unpin extents, so those extents
pinned by freeing log trees will remain in memory and lead to the leak.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:35 -08:00
Qu Wenruo
078025347c btrfs: Cleanup the btrfs_parse_options for remount.
Since remount will pending the new mount options to the original mount
options, which will make btrfs_parse_options check the old options then
new options, causing some stupid output like "enabling XXX" following by
"disable XXX".

This patch will add extra check before every btrfs_info to skip the
output from old options checking.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:34 -08:00
Qu Wenruo
3818aea275 btrfs: Add noinode_cache mount option
Add noinode_cache mount option for btrfs.

Since inode map cache involves all the btrfs_find_free_ino/return_ino
things and if just trigger the mount_opt,
an inode number get from inode map cache will not returned to inode map
cache.

To keep the find and return inode both in the same behavior,
a new bit in mount_opt, CHANGE_INODE_CACHE, is introduced for this idea.
CHANGE_INODE_CACHE is set/cleared in remounting, and the original
INODE_MAP_CACHE is set/cleared according to CHANGE_INODE_CACHE after a
success transaction.
Since find/return inode is all done between btrfs_start_transaction and
btrfs_commit_transaction, this will keep consistent behavior.

Also noinode_cache mount option will not stop the caching_kthread.

Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:33 -08:00
Wang Shilong
ade2e0b3ee Btrfs: fix to search previous metadata extent item since skinny metadata
There is a bug that using btrfs_previous_item() to search metadata extent item.
This is because in btrfs_previous_item(), we need type match, however, since
skinny metada was introduced by josef, we may mix this two types. So just
use btrfs_previous_item() is not working right.

To keep btrfs_previous_item() like normal tree search, i introduce another
function btrfs_previous_extent_item().

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:33 -08:00
Wang Shilong
7c76edb77c Btrfs: fix missing skinny metadata check in scrub_stripe()
Check if we support skinny metadata firstly and fix to use
right type to search.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:32 -08:00
Filipe David Borba Manana
28e5dd8f35 Btrfs: fix send to not send non-aligned clone operations
It is possible for the send feature to send clone operations that
request a cloning range (offset + length) that is not aligned with
the block size. This makes the btrfs receive command send issue a
clone ioctl call that will fail, as the ioctl will return an -EINVAL
error because of the unaligned range.

Fix this by not sending clone operations for non block aligned ranges,
and instead send regular write operation for these (less common) cases.

The following xfstest reproduces this issue, which fails on the second
btrfs receive command without this change:

  seq=`basename $0`
  seqres=$RESULT_DIR/$seq
  echo "QA output created by $seq"

  tmp=`mktemp -d`

  status=1	# failure is the default!
  trap "_cleanup; exit \$status" 0 1 2 3 15

  _cleanup()
  {
      rm -fr $tmp
  }

  # get standard environment, filters and checks
  . ./common/rc
  . ./common/filter

  # real QA test starts here
  _supported_fs btrfs
  _supported_os Linux
  _require_scratch
  _need_to_be_root

  rm -f $seqres.full

  _scratch_mkfs >/dev/null 2>&1
  _scratch_mount

  $XFS_IO_PROG -f -c "truncate 819200" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $XFS_IO_PROG -c "falloc -k 819200 667648" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $XFS_IO_PROG -f -c "pwrite 1482752 2978" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $BTRFS_UTIL_PROG subvol snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap1 | \
      _filter_scratch

  $XFS_IO_PROG -f -c "truncate 883305" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $BTRFS_UTIL_PROG subvol snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2 | \
      _filter_scratch

  $BTRFS_UTIL_PROG send $SCRATCH_MNT/mysnap1 -f $tmp/1.snap 2>&1 | _filter_scratch
  $BTRFS_UTIL_PROG send -p $SCRATCH_MNT/mysnap1 $SCRATCH_MNT/mysnap2 \
      -f $tmp/2.snap 2>&1 | _filter_scratch

  md5sum $SCRATCH_MNT/foo | _filter_scratch
  md5sum $SCRATCH_MNT/mysnap1/foo | _filter_scratch
  md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch

  _scratch_unmount
  _check_btrfs_filesystem $SCRATCH_DEV
  _scratch_mkfs >/dev/null 2>&1
  _scratch_mount

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/1.snap
  md5sum $SCRATCH_MNT/mysnap1/foo | _filter_scratch

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/2.snap
  md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch

  _scratch_unmount
  _check_btrfs_filesystem $SCRATCH_DEV

  status=0
  exit

The tests expected output is:

  QA output created by 025
  FSSync 'SCRATCH_MNT'
  FSSync 'SCRATCH_MNT'
  wrote 2978/2978 bytes at offset 1482752
  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
  FSSync 'SCRATCH_MNT'
  Create a readonly snapshot of 'SCRATCH_MNT' in 'SCRATCH_MNT/mysnap1'
  FSSync 'SCRATCH_MNT'
  Create a readonly snapshot of 'SCRATCH_MNT' in 'SCRATCH_MNT/mysnap2'
  At subvol SCRATCH_MNT/mysnap1
  At subvol SCRATCH_MNT/mysnap2
  129b8eaee8d3c2bcad49bec596591cb3  SCRATCH_MNT/foo
  42b6369eae2a8725c1aacc0440e597aa  SCRATCH_MNT/mysnap1/foo
  129b8eaee8d3c2bcad49bec596591cb3  SCRATCH_MNT/mysnap2/foo
  At subvol mysnap1
  42b6369eae2a8725c1aacc0440e597aa  SCRATCH_MNT/mysnap1/foo
  At snapshot mysnap2
  129b8eaee8d3c2bcad49bec596591cb3  SCRATCH_MNT/mysnap2/foo

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:32 -08:00
Filipe David Borba Manana
14a958e678 Btrfs: fix btrfs boot when compiled as built-in
After the change titled "Btrfs: add support for inode properties", if
btrfs was built-in the kernel (i.e. not as a module), it would cause a
kernel panic, as reported recently by Fengguang:

[    2.024722] BUG: unable to handle kernel NULL pointer dereference at           (null)
[    2.027814] IP: [<ffffffff81501594>] crc32c+0xc/0x6b
[    2.028684] PGD 0
[    2.028684] Oops: 0000 [#1] SMP
[    2.028684] Modules linked in:
[    2.028684] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.13.0-rc7-04795-ga7b57c2 #1
[    2.028684] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    2.028684] task: ffff88000edba100 ti: ffff88000edd6000 task.ti: ffff88000edd6000
[    2.028684] RIP: 0010:[<ffffffff81501594>]  [<ffffffff81501594>] crc32c+0xc/0x6b
[    2.028684] RSP: 0000:ffff88000edd7e58  EFLAGS: 00010246
[    2.028684] RAX: 0000000000000000 RBX: ffffffff82295550 RCX: 0000000000000000
[    2.028684] RDX: 0000000000000011 RSI: ffffffff81efe393 RDI: 00000000fffffffe
[    2.028684] RBP: ffff88000edd7e60 R08: 0000000000000003 R09: 0000000000015d20
[    2.028684] R10: ffffffff81ef225e R11: ffffffff811b0222 R12: ffffffffffffffff
[    2.028684] R13: 0000000000000239 R14: 0000000000000000 R15: 0000000000000000
[    2.028684] FS:  0000000000000000(0000) GS:ffff88000fa00000(0000) knlGS:0000000000000000
[    2.028684] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    2.028684] CR2: 0000000000000000 CR3: 000000000220c000 CR4: 00000000000006f0
[    2.028684] Stack:
[    2.028684]  ffffffff82295550 ffff88000edd7e80 ffffffff8238af62 ffffffff8238ac05
[    2.028684]  0000000000000000 ffff88000edd7e98 ffffffff8238ac0f ffffffff8238ac05
[    2.028684]  ffff88000edd7f08 ffffffff810002ba ffff88000edd7f00 ffffffff810e2404
[    2.028684] Call Trace:
[    2.028684]  [<ffffffff8238af62>] btrfs_props_init+0x4f/0x96
[    2.028684]  [<ffffffff8238ac05>] ? ftrace_define_fields_btrfs_space_reservation+0x145/0x145
[    2.028684]  [<ffffffff8238ac0f>] init_btrfs_fs+0xa/0xf0
[    2.028684]  [<ffffffff8238ac05>] ? ftrace_define_fields_btrfs_space_reservation+0x145/0x145
[    2.028684]  [<ffffffff810002ba>] do_one_initcall+0xa4/0x13a
[    2.028684]  [<ffffffff810e2404>] ? parse_args+0x25f/0x33d
[    2.028684]  [<ffffffff8234cf75>] kernel_init_freeable+0x1aa/0x230
[    2.028684]  [<ffffffff8234c785>] ? do_early_param+0x88/0x88
[    2.028684]  [<ffffffff819f61b5>] ? rest_init+0x89/0x89
[    2.028684]  [<ffffffff819f61c3>] kernel_init+0xe/0x109

The issue here is that the initialization function of btrfs (super.c:init_btrfs_fs)
started using crc32c (from lib/libcrc32c.c). But when it needs to call crc32c (as
part of the properties initialization routine), the libcrc32c is not yet initialized,
so crc32c derreferenced a NULL pointer (lib/libcrc32c.c:tfm), causing the kernel
panic on boot.

The approach to fix this is to use crypto component directly to use its crc32c (which
is basically what lib/libcrc32c.c is, a wrapper around crypto). This is what ext4 is
doing as well, it uses crypto directly to get crc32c functionality.

Verified this works both when btrfs is built-in and when it's loadable kernel module.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:31 -08:00
Filipe David Borba Manana
c57c2b3ed2 Btrfs: unlock inodes in correct order in clone ioctl
In the clone ioctl, when the source and target inodes are different,
we can acquire their mutexes in 2 possible different orders. After
we're done cloning, we were releasing the mutexes always in the same
order - the most correct way of doing it is to release them by the
reverse order they were acquired.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:30 -08:00
Wang Shilong
f499e40fd9 Btrfs: optimize to remove unnecessary removal with ulist reallocation
Here we are not going to free memory, no need to remove every node
one by one, just init root node here is ok.

Cc:  Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:30 -08:00
Liu Bo
de6e820066 Btrfs: release subvolume's block_rsv before transaction commit
We don't have to keep subvolume's block_rsv during transaction commit,
and within transaction commit, we may also need the free space reclaimed
from this block_rsv to process delayed refs.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:29 -08:00
Miao Xie
f1de968376 Btrfs: fix the race between write back and nocow buffered write
When we ran the 274th case of xfstests with nodatacow mount option,
We met the following warning message:
WARNING: CPU: 1 PID: 14185 at fs/btrfs/extent-tree.c:3734 btrfs_free_reserved_data_space+0xa6/0xd0

It is caused by the race between the write back and nocow buffered
write:
  Task1				Task2
  __btrfs_buffered_write()
    skip data reservation
    reserve the metadata space
    copy the data
    dirty the pages
    unlock the pages
				write back the pages
				release the data space
   				  becasue there is no
				  noreserve flag
   set the noreserve flag

This patch fixes this problem by unlocking the pages after
the noreserve flag is set.

Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:28 -08:00
Josef Bacik
7ef81ac86c Btrfs: only process as many file extents as there are refs
The backref walking code will search down to the key it is looking for and then
proceed to walk _all_ of the extents on the file until it hits the end.  This is
suboptimal with large files, we only need to look for as many extents as we have
references for that inode.  I have a testcase that creates a randomly written 4
gig file and before this patch it took 6min 30sec to do the initial send, with
this patch it takes 2min 30sec to do the intial send.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:28 -08:00
Josef Bacik
3a6d75e846 Btrfs: fix qgroup rescan to work with skinny metadata
Could have sworn I fixed this before but apparently not.  This makes us pass
btrfs/022 with skinny metadata enabled.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:27 -08:00