| Age | Commit message (Collapse) | Author |
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We have a race between enabling quotas end subvolume creation that cause
subvolume creation to fail with -EINVAL, and the following diagram shows
how it happens:
CPU 0 CPU 1
btrfs_ioctl()
btrfs_ioctl_quota_ctl()
btrfs_quota_enable()
mutex_lock(fs_info->qgroup_ioctl_lock)
btrfs_ioctl()
create_subvol()
btrfs_qgroup_inherit()
-> save fs_info->quota_root
into quota_root
-> stores a NULL value
-> tries to lock the mutex
qgroup_ioctl_lock
-> blocks waiting for
the task at CPU0
-> sets BTRFS_FS_QUOTA_ENABLED in fs_info
-> sets quota_root in fs_info->quota_root
(non-NULL value)
mutex_unlock(fs_info->qgroup_ioctl_lock)
-> checks quota enabled
flag is set
-> returns -EINVAL because
fs_info->quota_root was
NULL before it acquired
the mutex
qgroup_ioctl_lock
-> ioctl returns -EINVAL
Returning -EINVAL to user space will be confusing if all the arguments
passed to the subvolume creation ioctl were valid.
Fix it by grabbing the value from fs_info->quota_root after acquiring
the mutex.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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When doing an incremental send, due to the need of delaying directory move
(rename) operations we can end up in infinite loop at
apply_children_dir_moves().
An example scenario that triggers this problem is described below, where
directory names correspond to the numbers of their respective inodes.
Parent snapshot:
.
|--- 261/
|--- 271/
|--- 266/
|--- 259/
|--- 260/
| |--- 267
|
|--- 264/
| |--- 258/
| |--- 257/
|
|--- 265/
|--- 268/
|--- 269/
| |--- 262/
|
|--- 270/
|--- 272/
| |--- 263/
| |--- 275/
|
|--- 274/
|--- 273/
Send snapshot:
.
|-- 275/
|-- 274/
|-- 273/
|-- 262/
|-- 269/
|-- 258/
|-- 271/
|-- 268/
|-- 267/
|-- 270/
|-- 259/
| |-- 265/
|
|-- 272/
|-- 257/
|-- 260/
|-- 264/
|-- 263/
|-- 261/
|-- 266/
When processing inode 257 we delay its move (rename) operation because its
new parent in the send snapshot, inode 272, was not yet processed. Then
when processing inode 272, we delay the move operation for that inode
because inode 274 is its ancestor in the send snapshot. Finally we delay
the move operation for inode 274 when processing it because inode 275 is
its new parent in the send snapshot and was not yet moved.
When finishing processing inode 275, we start to do the move operations
that were previously delayed (at apply_children_dir_moves()), resulting in
the following iterations:
1) We issue the move operation for inode 274;
2) Because inode 262 depended on the move operation of inode 274 (it was
delayed because 274 is its ancestor in the send snapshot), we issue the
move operation for inode 262;
3) We issue the move operation for inode 272, because it was delayed by
inode 274 too (ancestor of 272 in the send snapshot);
4) We issue the move operation for inode 269 (it was delayed by 262);
5) We issue the move operation for inode 257 (it was delayed by 272);
6) We issue the move operation for inode 260 (it was delayed by 272);
7) We issue the move operation for inode 258 (it was delayed by 269);
8) We issue the move operation for inode 264 (it was delayed by 257);
9) We issue the move operation for inode 271 (it was delayed by 258);
10) We issue the move operation for inode 263 (it was delayed by 264);
11) We issue the move operation for inode 268 (it was delayed by 271);
12) We verify if we can issue the move operation for inode 270 (it was
delayed by 271). We detect a path loop in the current state, because
inode 267 needs to be moved first before we can issue the move
operation for inode 270. So we delay again the move operation for
inode 270, this time we will attempt to do it after inode 267 is
moved;
13) We issue the move operation for inode 261 (it was delayed by 263);
14) We verify if we can issue the move operation for inode 266 (it was
delayed by 263). We detect a path loop in the current state, because
inode 270 needs to be moved first before we can issue the move
operation for inode 266. So we delay again the move operation for
inode 266, this time we will attempt to do it after inode 270 is
moved (its move operation was delayed in step 12);
15) We issue the move operation for inode 267 (it was delayed by 268);
16) We verify if we can issue the move operation for inode 266 (it was
delayed by 270). We detect a path loop in the current state, because
inode 270 needs to be moved first before we can issue the move
operation for inode 266. So we delay again the move operation for
inode 266, this time we will attempt to do it after inode 270 is
moved (its move operation was delayed in step 12). So here we added
again the same delayed move operation that we added in step 14;
17) We attempt again to see if we can issue the move operation for inode
266, and as in step 16, we realize we can not due to a path loop in
the current state due to a dependency on inode 270. Again we delay
inode's 266 rename to happen after inode's 270 move operation, adding
the same dependency to the empty stack that we did in steps 14 and 16.
The next iteration will pick the same move dependency on the stack
(the only entry) and realize again there is still a path loop and then
again the same dependency to the stack, over and over, resulting in
an infinite loop.
So fix this by preventing adding the same move dependency entries to the
stack by removing each pending move record from the red black tree of
pending moves. This way the next call to get_pending_dir_moves() will
not return anything for the current parent inode.
A test case for fstests, with this reproducer, follows soon.
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[Wrote changelog with example and more clear explanation]
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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We were using the path name received from user space without checking that
it is null terminated. While btrfs-progs is well behaved and does proper
validation and null termination, someone could call the ioctl and pass
a non-null terminated patch, leading to buffer overrun problems in the
kernel. The ioctl is protected by CAP_SYS_ADMIN.
So just set the last byte of the path to a null character, similar to what
we do in other ioctls (add/remove/resize device, snapshot creation, etc).
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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After the simplification of the fast fsync patch done recently by commit
b5e6c3e170b7 ("btrfs: always wait on ordered extents at fsync time") and
commit e7175a692765 ("btrfs: remove the wait ordered logic in the
log_one_extent path"), we got a very short time window where we can get
extents logged without writeback completing first or extents logged
without logging the respective data checksums. Both issues can only happen
when doing a non-full (fast) fsync.
As soon as we enter btrfs_sync_file() we trigger writeback, then lock the
inode and then wait for the writeback to complete before starting to log
the inode. However before we acquire the inode's lock and after we started
writeback, it's possible that more writes happened and dirtied more pages.
If that happened and those pages get writeback triggered while we are
logging the inode (for example, the VM subsystem triggering it due to
memory pressure, or another concurrent fsync), we end up seeing the
respective extent maps in the inode's list of modified extents and will
log matching file extent items without waiting for the respective
ordered extents to complete, meaning that either of the following will
happen:
1) We log an extent after its writeback finishes but before its checksums
are added to the csum tree, leading to -EIO errors when attempting to
read the extent after a log replay.
2) We log an extent before its writeback finishes.
Therefore after the log replay we will have a file extent item pointing
to an unwritten extent (and without the respective data checksums as
well).
This could not happen before the fast fsync patch simplification, because
for any extent we found in the list of modified extents, we would wait for
its respective ordered extent to finish writeback or collect its checksums
for logging if it did not complete yet.
Fix this by triggering writeback again after acquiring the inode's lock
and before waiting for ordered extents to complete.
Fixes: e7175a692765 ("btrfs: remove the wait ordered logic in the log_one_extent path")
Fixes: b5e6c3e170b7 ("btrfs: always wait on ordered extents at fsync time")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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When a metadata read is served the endio routine btree_readpage_end_io_hook
is called which eventually runs the tree-checker. If tree-checker fails
to validate the read eb then it sets EXTENT_BUFFER_CORRUPT flag. This
leads to btree_read_extent_buffer_pages wrongly assuming that all
available copies of this extent buffer are wrong and failing prematurely.
Fix this modify btree_read_extent_buffer_pages to read all copies of
the data.
This failure was exhibitted in xfstests btrfs/124 which would
spuriously fail its balance operations. The reason was that when balance
was run following re-introduction of the missing raid1 disk
__btrfs_map_block would map the read request to stripe 0, which
corresponded to devid 2 (the disk which is being removed in the test):
item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 3553624064) itemoff 15975 itemsize 112
length 1073741824 owner 2 stripe_len 65536 type DATA|RAID1
io_align 65536 io_width 65536 sector_size 4096
num_stripes 2 sub_stripes 1
stripe 0 devid 2 offset 2156920832
dev_uuid 8466c350-ed0c-4c3b-b17d-6379b445d5c8
stripe 1 devid 1 offset 3553624064
dev_uuid 1265d8db-5596-477e-af03-df08eb38d2ca
This caused read requests for a checksum item that to be routed to the
stale disk which triggered the aforementioned logic involving
EXTENT_BUFFER_CORRUPT flag. This then triggered cascading failures of
the balance operation.
Fixes: a826d6dcb32d ("Btrfs: check items for correctness as we search")
CC: stable@vger.kernel.org # 4.4+
Suggested-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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There's a race between close_ctree() and cleaner_kthread().
close_ctree() sets btrfs_fs_closing(), and the cleaner stops when it
sees it set, but this is racy; the cleaner might have already checked
the bit and could be cleaning stuff. In particular, if it deletes unused
block groups, it will create delayed iputs for the free space cache
inodes. As of "btrfs: don't run delayed_iputs in commit", we're no
longer running delayed iputs after a commit. Therefore, if the cleaner
creates more delayed iputs after delayed iputs are run in
btrfs_commit_super(), we will leak inodes on unmount and get a busy
inode crash from the VFS.
Fix it by parking the cleaner before we actually close anything. Then,
any remaining delayed iputs will always be handled in
btrfs_commit_super(). This also ensures that the commit in close_ctree()
is really the last commit, so we can get rid of the commit in
cleaner_kthread().
The fstest/generic/475 followed by 476 can trigger a crash that
manifests as a slab corruption caused by accessing the freed kthread
structure by a wake up function. Sample trace:
[ 5657.077612] BUG: unable to handle kernel NULL pointer dereference at 00000000000000cc
[ 5657.079432] PGD 1c57a067 P4D 1c57a067 PUD da10067 PMD 0
[ 5657.080661] Oops: 0000 [#1] PREEMPT SMP
[ 5657.081592] CPU: 1 PID: 5157 Comm: fsstress Tainted: G W 4.19.0-rc8-default+ #323
[ 5657.083703] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014
[ 5657.086577] RIP: 0010:shrink_page_list+0x2f9/0xe90
[ 5657.091937] RSP: 0018:ffffb5c745c8f728 EFLAGS: 00010287
[ 5657.092953] RAX: 0000000000000074 RBX: ffffb5c745c8f830 RCX: 0000000000000000
[ 5657.094590] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9a8747fdf3d0
[ 5657.095987] RBP: ffffb5c745c8f9e0 R08: 0000000000000000 R09: 0000000000000000
[ 5657.097159] R10: ffff9a8747fdf5e8 R11: 0000000000000000 R12: ffffb5c745c8f788
[ 5657.098513] R13: ffff9a877f6ff2c0 R14: ffff9a877f6ff2c8 R15: dead000000000200
[ 5657.099689] FS: 00007f948d853b80(0000) GS:ffff9a877d600000(0000) knlGS:0000000000000000
[ 5657.101032] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5657.101953] CR2: 00000000000000cc CR3: 00000000684bd000 CR4: 00000000000006e0
[ 5657.103159] Call Trace:
[ 5657.103776] shrink_inactive_list+0x194/0x410
[ 5657.104671] shrink_node_memcg.constprop.84+0x39a/0x6a0
[ 5657.105750] shrink_node+0x62/0x1c0
[ 5657.106529] try_to_free_pages+0x1a4/0x500
[ 5657.107408] __alloc_pages_slowpath+0x2c9/0xb20
[ 5657.108418] __alloc_pages_nodemask+0x268/0x2b0
[ 5657.109348] kmalloc_large_node+0x37/0x90
[ 5657.110205] __kmalloc_node+0x236/0x310
[ 5657.111014] kvmalloc_node+0x3e/0x70
Fixes: 30928e9baac2 ("btrfs: don't run delayed_iputs in commit")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add trace ]
Signed-off-by: David Sterba <dsterba@suse.com>
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We currently allow cloning a range from a file which includes the last
block of the file even if the file's size is not aligned to the block
size. This is fine and useful when the destination file has the same size,
but when it does not and the range ends somewhere in the middle of the
destination file, it leads to corruption because the bytes between the EOF
and the end of the block have undefined data (when there is support for
discard/trimming they have a value of 0x00).
Example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ export foo_size=$((256 * 1024 + 100))
$ xfs_io -f -c "pwrite -S 0x3c 0 $foo_size" /mnt/foo
$ xfs_io -f -c "pwrite -S 0xb5 0 1M" /mnt/bar
$ xfs_io -c "reflink /mnt/foo 0 512K $foo_size" /mnt/bar
$ od -A d -t x1 /mnt/bar
0000000 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5
*
0524288 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c
*
0786528 3c 3c 3c 3c 00 00 00 00 00 00 00 00 00 00 00 00
0786544 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0790528 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5
*
1048576
The bytes in the range from 786532 (512Kb + 256Kb + 100 bytes) to 790527
(512Kb + 256Kb + 4Kb - 1) got corrupted, having now a value of 0x00 instead
of 0xb5.
This is similar to the problem we had for deduplication that got recently
fixed by commit de02b9f6bb65 ("Btrfs: fix data corruption when
deduplicating between different files").
Fix this by not allowing such operations to be performed and return the
errno -EINVAL to user space. This is what XFS is doing as well at the VFS
level. This change however now makes us return -EINVAL instead of
-EOPNOTSUPP for cases where the source range maps to an inline extent and
the destination range's end is smaller then the destination file's size,
since the detection of inline extents is done during the actual process of
dropping file extent items (at __btrfs_drop_extents()). Returning the
-EINVAL error is done early on and solely based on the input parameters
(offsets and length) and destination file's size. This makes us consistent
with XFS and anyone else supporting cloning since this case is now checked
at a higher level in the VFS and is where the -EINVAL will be returned
from starting with kernel 4.20 (the VFS changed was introduced in 4.20-rc1
by commit 07d19dc9fbe9 ("vfs: avoid problematic remapping requests into
partial EOF block"). So this change is more geared towards stable kernels,
as it's unlikely the new VFS checks get removed intentionally.
A test case for fstests follows soon, as well as an update to filter
existing tests that expect -EOPNOTSUPP to accept -EINVAL as well.
CC: <stable@vger.kernel.org> # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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If we attempt to deduplicate the last block of a file A into the middle of
a file B, and file A's size is not a multiple of the block size, we end
rounding the deduplication length to 0 bytes, to avoid the data corruption
issue fixed by commit de02b9f6bb65 ("Btrfs: fix data corruption when
deduplicating between different files"). However a length of zero will
cause the insertion of an extent state with a start value greater (by 1)
then the end value, leading to a corrupt extent state that will trigger a
warning and cause chaos such as an infinite loop during inode eviction.
Example trace:
[96049.833585] ------------[ cut here ]------------
[96049.833714] WARNING: CPU: 0 PID: 24448 at fs/btrfs/extent_io.c:436 insert_state+0x101/0x120 [btrfs]
[96049.833767] CPU: 0 PID: 24448 Comm: xfs_io Not tainted 4.19.0-rc7-btrfs-next-39 #1
[96049.833768] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
[96049.833780] RIP: 0010:insert_state+0x101/0x120 [btrfs]
[96049.833783] RSP: 0018:ffffafd2c3707af0 EFLAGS: 00010282
[96049.833785] RAX: 0000000000000000 RBX: 000000000004dfff RCX: 0000000000000006
[96049.833786] RDX: 0000000000000007 RSI: ffff99045c143230 RDI: ffff99047b2168a0
[96049.833787] RBP: ffff990457851cd0 R08: 0000000000000001 R09: 0000000000000000
[96049.833787] R10: ffffafd2c3707ab8 R11: 0000000000000000 R12: ffff9903b93b12c8
[96049.833788] R13: 000000000004e000 R14: ffffafd2c3707b80 R15: ffffafd2c3707b78
[96049.833790] FS: 00007f5c14e7d700(0000) GS:ffff99047b200000(0000) knlGS:0000000000000000
[96049.833791] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[96049.833792] CR2: 00007f5c146abff8 CR3: 0000000115f4c004 CR4: 00000000003606f0
[96049.833795] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[96049.833796] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[96049.833796] Call Trace:
[96049.833809] __set_extent_bit+0x46c/0x6a0 [btrfs]
[96049.833823] lock_extent_bits+0x6b/0x210 [btrfs]
[96049.833831] ? _raw_spin_unlock+0x24/0x30
[96049.833841] ? test_range_bit+0xdf/0x130 [btrfs]
[96049.833853] lock_extent_range+0x8e/0x150 [btrfs]
[96049.833864] btrfs_double_extent_lock+0x78/0xb0 [btrfs]
[96049.833875] btrfs_extent_same_range+0x14e/0x550 [btrfs]
[96049.833885] ? rcu_read_lock_sched_held+0x3f/0x70
[96049.833890] ? __kmalloc_node+0x2b0/0x2f0
[96049.833899] ? btrfs_dedupe_file_range+0x19a/0x280 [btrfs]
[96049.833909] btrfs_dedupe_file_range+0x270/0x280 [btrfs]
[96049.833916] vfs_dedupe_file_range_one+0xd9/0xe0
[96049.833919] vfs_dedupe_file_range+0x131/0x1b0
[96049.833924] do_vfs_ioctl+0x272/0x6e0
[96049.833927] ? __fget+0x113/0x200
[96049.833931] ksys_ioctl+0x70/0x80
[96049.833933] __x64_sys_ioctl+0x16/0x20
[96049.833937] do_syscall_64+0x60/0x1b0
[96049.833939] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[96049.833941] RIP: 0033:0x7f5c1478ddd7
[96049.833943] RSP: 002b:00007ffe15b196a8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[96049.833945] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5c1478ddd7
[96049.833946] RDX: 00005625ece322d0 RSI: 00000000c0189436 RDI: 0000000000000004
[96049.833947] RBP: 0000000000000000 R08: 00007f5c14a46f48 R09: 0000000000000040
[96049.833948] R10: 0000000000000541 R11: 0000000000000202 R12: 0000000000000000
[96049.833949] R13: 0000000000000000 R14: 0000000000000004 R15: 00005625ece322d0
[96049.833954] irq event stamp: 6196
[96049.833956] hardirqs last enabled at (6195): [<ffffffff91b00663>] console_unlock+0x503/0x640
[96049.833958] hardirqs last disabled at (6196): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
[96049.833959] softirqs last enabled at (6114): [<ffffffff92600370>] __do_softirq+0x370/0x421
[96049.833964] softirqs last disabled at (6095): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
[96049.833965] ---[ end trace db7b05f01b7fa10c ]---
[96049.935816] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
[96049.935822] irq event stamp: 6584
[96049.935823] hardirqs last enabled at (6583): [<ffffffff91b00663>] console_unlock+0x503/0x640
[96049.935825] hardirqs last disabled at (6584): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
[96049.935827] softirqs last enabled at (6328): [<ffffffff92600370>] __do_softirq+0x370/0x421
[96049.935828] softirqs last disabled at (6313): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
[96049.935829] ---[ end trace db7b05f01b7fa123 ]---
[96049.935840] ------------[ cut here ]------------
[96049.936065] WARNING: CPU: 1 PID: 24463 at fs/btrfs/extent_io.c:436 insert_state+0x101/0x120 [btrfs]
[96049.936107] CPU: 1 PID: 24463 Comm: umount Tainted: G W 4.19.0-rc7-btrfs-next-39 #1
[96049.936108] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
[96049.936117] RIP: 0010:insert_state+0x101/0x120 [btrfs]
[96049.936119] RSP: 0018:ffffafd2c3637bc0 EFLAGS: 00010282
[96049.936120] RAX: 0000000000000000 RBX: 000000000004dfff RCX: 0000000000000006
[96049.936121] RDX: 0000000000000007 RSI: ffff990445cf88e0 RDI: ffff99047b2968a0
[96049.936122] RBP: ffff990457851cd0 R08: 0000000000000001 R09: 0000000000000000
[96049.936123] R10: ffffafd2c3637b88 R11: 0000000000000000 R12: ffff9904574301e8
[96049.936124] R13: 000000000004e000 R14: ffffafd2c3637c50 R15: ffffafd2c3637c48
[96049.936125] FS: 00007fe4b87e72c0(0000) GS:ffff99047b280000(0000) knlGS:0000000000000000
[96049.936126] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[96049.936128] CR2: 00005562e52618d8 CR3: 00000001151c8005 CR4: 00000000003606e0
[96049.936129] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[96049.936131] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[96049.936131] Call Trace:
[96049.936141] __set_extent_bit+0x46c/0x6a0 [btrfs]
[96049.936154] lock_extent_bits+0x6b/0x210 [btrfs]
[96049.936167] btrfs_evict_inode+0x1e1/0x5a0 [btrfs]
[96049.936172] evict+0xbf/0x1c0
[96049.936174] dispose_list+0x51/0x80
[96049.936176] evict_inodes+0x193/0x1c0
[96049.936180] generic_shutdown_super+0x3f/0x110
[96049.936182] kill_anon_super+0xe/0x30
[96049.936189] btrfs_kill_super+0x13/0x100 [btrfs]
[96049.936191] deactivate_locked_super+0x3a/0x70
[96049.936193] cleanup_mnt+0x3b/0x80
[96049.936195] task_work_run+0x93/0xc0
[96049.936198] exit_to_usermode_loop+0xfa/0x100
[96049.936201] do_syscall_64+0x17f/0x1b0
[96049.936202] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[96049.936204] RIP: 0033:0x7fe4b80cfb37
[96049.936206] RSP: 002b:00007ffff092b688 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[96049.936207] RAX: 0000000000000000 RBX: 00005562e5259060 RCX: 00007fe4b80cfb37
[96049.936208] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00005562e525faa0
[96049.936209] RBP: 00005562e525faa0 R08: 00005562e525f770 R09: 0000000000000015
[96049.936210] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fe4b85d1e64
[96049.936211] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
[96049.936211] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
[96049.936216] irq event stamp: 6616
[96049.936219] hardirqs last enabled at (6615): [<ffffffff91b00663>] console_unlock+0x503/0x640
[96049.936219] hardirqs last disabled at (6616): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
[96049.936222] softirqs last enabled at (6328): [<ffffffff92600370>] __do_softirq+0x370/0x421
[96049.936222] softirqs last disabled at (6313): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
[96049.936223] ---[ end trace db7b05f01b7fa124 ]---
The second stack trace, from inode eviction, is repeated forever due to
the infinite loop during eviction.
This is the same type of problem fixed way back in 2015 by commit
113e8283869b ("Btrfs: fix inode eviction infinite loop after extent_same
ioctl") and commit ccccf3d67294 ("Btrfs: fix inode eviction infinite loop
after cloning into it").
So fix this by returning immediately if the deduplication range length
gets rounded down to 0 bytes, as there is nothing that needs to be done in
such case.
Example reproducer:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0xe6 0 100" /mnt/foo
$ xfs_io -f -c "pwrite -S 0xe6 0 1M" /mnt/bar
# Unmount the filesystem and mount it again so that we start without any
# extent state records when we ask for the deduplication.
$ umount /mnt
$ mount /dev/sdb /mnt
$ xfs_io -c "dedupe /mnt/foo 0 500K 100" /mnt/bar
# This unmount triggers the infinite loop.
$ umount /mnt
A test case for fstests will follow soon.
Fixes: de02b9f6bb65 ("Btrfs: fix data corruption when deduplicating between different files")
CC: <stable@vger.kernel.org> # 4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When we are writing out a free space cache, during the transaction commit
phase, we can end up in a deadlock which results in a stack trace like the
following:
schedule+0x28/0x80
btrfs_tree_read_lock+0x8e/0x120 [btrfs]
? finish_wait+0x80/0x80
btrfs_read_lock_root_node+0x2f/0x40 [btrfs]
btrfs_search_slot+0xf6/0x9f0 [btrfs]
? evict_refill_and_join+0xd0/0xd0 [btrfs]
? inode_insert5+0x119/0x190
btrfs_lookup_inode+0x3a/0xc0 [btrfs]
? kmem_cache_alloc+0x166/0x1d0
btrfs_iget+0x113/0x690 [btrfs]
__lookup_free_space_inode+0xd8/0x150 [btrfs]
lookup_free_space_inode+0x5b/0xb0 [btrfs]
load_free_space_cache+0x7c/0x170 [btrfs]
? cache_block_group+0x72/0x3b0 [btrfs]
cache_block_group+0x1b3/0x3b0 [btrfs]
? finish_wait+0x80/0x80
find_free_extent+0x799/0x1010 [btrfs]
btrfs_reserve_extent+0x9b/0x180 [btrfs]
btrfs_alloc_tree_block+0x1b3/0x4f0 [btrfs]
__btrfs_cow_block+0x11d/0x500 [btrfs]
btrfs_cow_block+0xdc/0x180 [btrfs]
btrfs_search_slot+0x3bd/0x9f0 [btrfs]
btrfs_lookup_inode+0x3a/0xc0 [btrfs]
? kmem_cache_alloc+0x166/0x1d0
btrfs_update_inode_item+0x46/0x100 [btrfs]
cache_save_setup+0xe4/0x3a0 [btrfs]
btrfs_start_dirty_block_groups+0x1be/0x480 [btrfs]
btrfs_commit_transaction+0xcb/0x8b0 [btrfs]
At cache_save_setup() we need to update the inode item of a block group's
cache which is located in the tree root (fs_info->tree_root), which means
that it may result in COWing a leaf from that tree. If that happens we
need to find a free metadata extent and while looking for one, if we find
a block group which was not cached yet we attempt to load its cache by
calling cache_block_group(). However this function will try to load the
inode of the free space cache, which requires finding the matching inode
item in the tree root - if that inode item is located in the same leaf as
the inode item of the space cache we are updating at cache_save_setup(),
we end up in a deadlock, since we try to obtain a read lock on the same
extent buffer that we previously write locked.
So fix this by using the tree root's commit root when searching for a
block group's free space cache inode item when we are attempting to load
a free space cache. This is safe since block groups once loaded stay in
memory forever, as well as their caches, so after they are first loaded
we will never need to read their inode items again. For new block groups,
once they are created they get their ->cached field set to
BTRFS_CACHE_FINISHED meaning we will not need to read their inode item.
Reported-by: Andrew Nelson <andrew.s.nelson@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CAPTELenq9x5KOWuQ+fa7h1r3nsJG8vyiTH8+ifjURc_duHh2Wg@mail.gmail.com/
Fixes: 9d66e233c704 ("Btrfs: load free space cache if it exists")
Tested-by: Andrew Nelson <andrew.s.nelson@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Note: this patch fixes a problem in a feature outside of btrfs ("kernel
hacking: add a config option to disable compiler auto-inlining") and is
applied ahead of time due to cross-subsystem dependencies.
On 32-bit ARM with gcc-8, I see a link error with the addition of the
CONFIG_NO_AUTO_INLINE option:
fs/btrfs/super.o: In function `btrfs_statfs':
super.c:(.text+0x67b8): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x67fc): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x6858): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x6920): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x693c): undefined reference to `__aeabi_uldivmod'
fs/btrfs/super.o:super.c:(.text+0x6958): more undefined references to `__aeabi_uldivmod' follow
So far this is the only file that shows the behavior, so I'd propose
to just work around it by marking the functions as 'static inline'
that normally get inlined here.
The reference to __aeabi_uldivmod comes from a div_u64() which has an
optimization for a constant division that uses a straight '/' operator
when the result should be known to the compiler. My interpretation is
that as we turn off inlining, gcc still expects the result to be constant
but fails to use that constant value.
Link: https://lkml.kernel.org/r/20181103153941.1881966-1-arnd@arndb.de
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[ add the note ]
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
block_group_err shows the group system as a decimal value with a '0x'
prefix, which is somewhat misleading.
Fix it to print hexadecimal, as was intended.
Fixes: fce466eab7ac6 ("btrfs: tree-checker: Verify block_group_item")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Recently we got a massive simplification for fsync, where for the fast
path we no longer log new extents while their respective ordered extents
are still running.
However that simplification introduced a subtle regression for the case
where we use a ranged fsync (msync). Consider the following example:
CPU 0 CPU 1
mmap write to range [2Mb, 4Mb[
mmap write to range [512Kb, 1Mb[
msync range [512K, 1Mb[
--> triggers fast fsync
(BTRFS_INODE_NEEDS_FULL_SYNC
not set)
--> creates extent map A for this
range and adds it to list of
modified extents
--> starts ordered extent A for
this range
--> waits for it to complete
writeback triggered for range
[2Mb, 4Mb[
--> create extent map B and
adds it to the list of
modified extents
--> creates ordered extent B
--> start looking for and logging
modified extents
--> logs extent maps A and B
--> finds checksums for extent A
in the csum tree, but not for
extent B
fsync (msync) finishes
--> ordered extent B
finishes and its
checksums are added
to the csum tree
<power cut>
After replaying the log, we have the extent covering the range [2Mb, 4Mb[
but do not have the data checksum items covering that file range.
This happens because at the very beginning of an fsync (btrfs_sync_file())
we start and wait for IO in the given range [512Kb, 1Mb[ and therefore
wait for any ordered extents in that range to complete before we start
logging the extents. However if right before we start logging the extent
in our range [512Kb, 1Mb[, writeback is started for any other dirty range,
such as the range [2Mb, 4Mb[ due to memory pressure or a concurrent fsync
or msync (btrfs_sync_file() starts writeback before acquiring the inode's
lock), an ordered extent is created for that other range and a new extent
map is created to represent that range and added to the inode's list of
modified extents.
That means that we will see that other extent in that list when collecting
extents for logging (done at btrfs_log_changed_extents()) and log the
extent before the respective ordered extent finishes - namely before the
checksum items are added to the checksums tree, which is where
log_extent_csums() looks for the checksums, therefore making us log an
extent without logging its checksums. Before that massive simplification
of fsync, this wasn't a problem because besides looking for checkums in
the checksums tree, we also looked for them in any ordered extent still
running.
The consequence of data checksums missing for a file range is that users
attempting to read the affected file range will get -EIO errors and dmesg
reports the following:
[10188.358136] BTRFS info (device sdc): no csum found for inode 297 start 57344
[10188.359278] BTRFS warning (device sdc): csum failed root 5 ino 297 off 57344 csum 0x98f94189 expected csum 0x00000000 mirror 1
So fix this by skipping extents outside of our logging range at
btrfs_log_changed_extents() and leaving them on the list of modified
extents so that any subsequent ranged fsync may collect them if needed.
Also, if we find a hole extent outside of the range still log it, just
to prevent having gaps between extent items after replaying the log,
otherwise fsck will complain when we are not using the NO_HOLES feature
(fstest btrfs/056 triggers such case).
Fixes: e7175a692765 ("btrfs: remove the wait ordered logic in the log_one_extent path")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When running generic/475, we may get the following warning in dmesg:
[ 6902.102154] WARNING: CPU: 3 PID: 18013 at fs/btrfs/extent-tree.c:9776 btrfs_free_block_groups+0x2af/0x3b0 [btrfs]
[ 6902.109160] CPU: 3 PID: 18013 Comm: umount Tainted: G W O 4.19.0-rc8+ #8
[ 6902.110971] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
[ 6902.112857] RIP: 0010:btrfs_free_block_groups+0x2af/0x3b0 [btrfs]
[ 6902.118921] RSP: 0018:ffffc9000459bdb0 EFLAGS: 00010286
[ 6902.120315] RAX: ffff880175050bb0 RBX: ffff8801124a8000 RCX: 0000000000170007
[ 6902.121969] RDX: 0000000000000002 RSI: 0000000000170007 RDI: ffffffff8125fb74
[ 6902.123716] RBP: ffff880175055d10 R08: 0000000000000000 R09: 0000000000000000
[ 6902.125417] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880175055d88
[ 6902.127129] R13: ffff880175050bb0 R14: 0000000000000000 R15: dead000000000100
[ 6902.129060] FS: 00007f4507223780(0000) GS:ffff88017ba00000(0000) knlGS:0000000000000000
[ 6902.130996] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6902.132558] CR2: 00005623599cac78 CR3: 000000014b700001 CR4: 00000000003606e0
[ 6902.134270] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 6902.135981] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 6902.137836] Call Trace:
[ 6902.138939] close_ctree+0x171/0x330 [btrfs]
[ 6902.140181] ? kthread_stop+0x146/0x1f0
[ 6902.141277] generic_shutdown_super+0x6c/0x100
[ 6902.142517] kill_anon_super+0x14/0x30
[ 6902.143554] btrfs_kill_super+0x13/0x100 [btrfs]
[ 6902.144790] deactivate_locked_super+0x2f/0x70
[ 6902.146014] cleanup_mnt+0x3b/0x70
[ 6902.147020] task_work_run+0x9e/0xd0
[ 6902.148036] do_syscall_64+0x470/0x600
[ 6902.149142] ? trace_hardirqs_off_thunk+0x1a/0x1c
[ 6902.150375] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 6902.151640] RIP: 0033:0x7f45077a6a7b
[ 6902.157324] RSP: 002b:00007ffd589f3e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 6902.159187] RAX: 0000000000000000 RBX: 000055e8eec732b0 RCX: 00007f45077a6a7b
[ 6902.160834] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000055e8eec73490
[ 6902.162526] RBP: 0000000000000000 R08: 000055e8eec734b0 R09: 00007ffd589f26c0
[ 6902.164141] R10: 0000000000000000 R11: 0000000000000246 R12: 000055e8eec73490
[ 6902.165815] R13: 00007f4507ac61a4 R14: 0000000000000000 R15: 00007ffd589f40d8
[ 6902.167553] irq event stamp: 0
[ 6902.168998] hardirqs last enabled at (0): [<0000000000000000>] (null)
[ 6902.170731] hardirqs last disabled at (0): [<ffffffff810cd810>] copy_process.part.55+0x3b0/0x1f00
[ 6902.172773] softirqs last enabled at (0): [<ffffffff810cd810>] copy_process.part.55+0x3b0/0x1f00
[ 6902.174671] softirqs last disabled at (0): [<0000000000000000>] (null)
[ 6902.176407] ---[ end trace 463138c2986b275c ]---
[ 6902.177636] BTRFS info (device dm-3): space_info 4 has 273465344 free, is not full
[ 6902.179453] BTRFS info (device dm-3): space_info total=276824064, used=4685824, pinned=18446744073708158976, reserved=0, may_use=0, readonly=65536
In the above line there's "pinned=18446744073708158976" which is an
unsigned u64 value of -1392640, an obvious underflow.
When transaction_kthread is running cleanup_transaction(), another
fsstress is running btrfs_commit_transaction(). The
btrfs_finish_extent_commit() may get the same range as
btrfs_destroy_pinned_extent() got, which causes the pinned underflow.
Fixes: d4b450cd4b33 ("Btrfs: fix race between transaction commit and empty block group removal")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When the cow_file_range fails, the related resources are unlocked
according to the range [start..end), so the unlock cannot be repeated in
run_delalloc_nocow.
In some cases (e.g. cur_offset <= end && cow_start != -1), cur_offset is
not updated correctly, so move the cur_offset update before
cow_file_range.
kernel BUG at mm/page-writeback.c:2663!
Internal error: Oops - BUG: 0 [#1] SMP
CPU: 3 PID: 31525 Comm: kworker/u8:7 Tainted: P O
Hardware name: Realtek_RTD1296 (DT)
Workqueue: writeback wb_workfn (flush-btrfs-1)
task: ffffffc076db3380 ti: ffffffc02e9ac000 task.ti: ffffffc02e9ac000
PC is at clear_page_dirty_for_io+0x1bc/0x1e8
LR is at clear_page_dirty_for_io+0x14/0x1e8
pc : [<ffffffc00033c91c>] lr : [<ffffffc00033c774>] pstate: 40000145
sp : ffffffc02e9af4f0
Process kworker/u8:7 (pid: 31525, stack limit = 0xffffffc02e9ac020)
Call trace:
[<ffffffc00033c91c>] clear_page_dirty_for_io+0x1bc/0x1e8
[<ffffffbffc514674>] extent_clear_unlock_delalloc+0x1e4/0x210 [btrfs]
[<ffffffbffc4fb168>] run_delalloc_nocow+0x3b8/0x948 [btrfs]
[<ffffffbffc4fb948>] run_delalloc_range+0x250/0x3a8 [btrfs]
[<ffffffbffc514c0c>] writepage_delalloc.isra.21+0xbc/0x1d8 [btrfs]
[<ffffffbffc516048>] __extent_writepage+0xe8/0x248 [btrfs]
[<ffffffbffc51630c>] extent_write_cache_pages.isra.17+0x164/0x378 [btrfs]
[<ffffffbffc5185a8>] extent_writepages+0x48/0x68 [btrfs]
[<ffffffbffc4f5828>] btrfs_writepages+0x20/0x30 [btrfs]
[<ffffffc00033d758>] do_writepages+0x30/0x88
[<ffffffc0003ba0f4>] __writeback_single_inode+0x34/0x198
[<ffffffc0003ba6c4>] writeback_sb_inodes+0x184/0x3c0
[<ffffffc0003ba96c>] __writeback_inodes_wb+0x6c/0xc0
[<ffffffc0003bac20>] wb_writeback+0x1b8/0x1c0
[<ffffffc0003bb0f0>] wb_workfn+0x150/0x250
[<ffffffc0002b0014>] process_one_work+0x1dc/0x388
[<ffffffc0002b02f0>] worker_thread+0x130/0x500
[<ffffffc0002b6344>] kthread+0x10c/0x110
[<ffffffc000284590>] ret_from_fork+0x10/0x40
Code: d503201f a9025bb5 a90363b7 f90023b9 (d4210000)
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We were iterating a block group's free space cache rbtree without locking
first the lock that protects it (the free_space_ctl->free_space_offset
rbtree is protected by the free_space_ctl->tree_lock spinlock).
KASAN reported an use-after-free problem when iterating such a rbtree due
to a concurrent rbtree delete:
[ 9520.359168] ==================================================================
[ 9520.359656] BUG: KASAN: use-after-free in rb_next+0x13/0x90
[ 9520.359949] Read of size 8 at addr ffff8800b7ada500 by task btrfs-transacti/1721
[ 9520.360357]
[ 9520.360530] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G L 4.19.0-rc8-nbor #555
[ 9520.360990] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 9520.362682] Call Trace:
[ 9520.362887] dump_stack+0xa4/0xf5
[ 9520.363146] print_address_description+0x78/0x280
[ 9520.363412] kasan_report+0x263/0x390
[ 9520.363650] ? rb_next+0x13/0x90
[ 9520.363873] __asan_load8+0x54/0x90
[ 9520.364102] rb_next+0x13/0x90
[ 9520.364380] btrfs_dump_free_space+0x146/0x160 [btrfs]
[ 9520.364697] dump_space_info+0x2cd/0x310 [btrfs]
[ 9520.364997] btrfs_reserve_extent+0x1ee/0x1f0 [btrfs]
[ 9520.365310] __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs]
[ 9520.365646] ? btrfs_update_time+0x180/0x180 [btrfs]
[ 9520.365923] ? _raw_spin_unlock+0x27/0x40
[ 9520.366204] ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs]
[ 9520.366549] btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs]
[ 9520.366880] cache_save_setup+0x42e/0x580 [btrfs]
[ 9520.367220] ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs]
[ 9520.367518] ? lock_downgrade+0x2f0/0x2f0
[ 9520.367799] ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs]
[ 9520.368104] ? kasan_check_read+0x11/0x20
[ 9520.368349] ? do_raw_spin_unlock+0xa8/0x140
[ 9520.368638] btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs]
[ 9520.368978] ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs]
[ 9520.369282] ? do_raw_spin_unlock+0xa8/0x140
[ 9520.369534] ? _raw_spin_unlock+0x27/0x40
[ 9520.369811] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.370137] commit_cowonly_roots+0x4b9/0x610 [btrfs]
[ 9520.370560] ? commit_fs_roots+0x350/0x350 [btrfs]
[ 9520.370926] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.371285] btrfs_commit_transaction+0x5e5/0x10e0 [btrfs]
[ 9520.371612] ? btrfs_apply_pending_changes+0x90/0x90 [btrfs]
[ 9520.371943] ? start_transaction+0x168/0x6c0 [btrfs]
[ 9520.372257] transaction_kthread+0x21c/0x240 [btrfs]
[ 9520.372537] kthread+0x1d2/0x1f0
[ 9520.372793] ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs]
[ 9520.373090] ? kthread_park+0xb0/0xb0
[ 9520.373329] ret_from_fork+0x3a/0x50
[ 9520.373567]
[ 9520.373738] Allocated by task 1804:
[ 9520.373974] kasan_kmalloc+0xff/0x180
[ 9520.374208] kasan_slab_alloc+0x11/0x20
[ 9520.374447] kmem_cache_alloc+0xfc/0x2d0
[ 9520.374731] __btrfs_add_free_space+0x40/0x580 [btrfs]
[ 9520.375044] unpin_extent_range+0x4f7/0x7a0 [btrfs]
[ 9520.375383] btrfs_finish_extent_commit+0x15f/0x4d0 [btrfs]
[ 9520.375707] btrfs_commit_transaction+0xb06/0x10e0 [btrfs]
[ 9520.376027] btrfs_alloc_data_chunk_ondemand+0x237/0x5c0 [btrfs]
[ 9520.376365] btrfs_check_data_free_space+0x81/0xd0 [btrfs]
[ 9520.376689] btrfs_delalloc_reserve_space+0x25/0x80 [btrfs]
[ 9520.377018] btrfs_direct_IO+0x42e/0x6d0 [btrfs]
[ 9520.377284] generic_file_direct_write+0x11e/0x220
[ 9520.377587] btrfs_file_write_iter+0x472/0xac0 [btrfs]
[ 9520.377875] aio_write+0x25c/0x360
[ 9520.378106] io_submit_one+0xaa0/0xdc0
[ 9520.378343] __se_sys_io_submit+0xfa/0x2f0
[ 9520.378589] __x64_sys_io_submit+0x43/0x50
[ 9520.378840] do_syscall_64+0x7d/0x240
[ 9520.379081] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 9520.379387]
[ 9520.379557] Freed by task 1802:
[ 9520.379782] __kasan_slab_free+0x173/0x260
[ 9520.380028] kasan_slab_free+0xe/0x10
[ 9520.380262] kmem_cache_free+0xc1/0x2c0
[ 9520.380544] btrfs_find_space_for_alloc+0x4cd/0x4e0 [btrfs]
[ 9520.380866] find_free_extent+0xa99/0x17e0 [btrfs]
[ 9520.381166] btrfs_reserve_extent+0xd5/0x1f0 [btrfs]
[ 9520.381474] btrfs_get_blocks_direct+0x60b/0xbd0 [btrfs]
[ 9520.381761] __blockdev_direct_IO+0x10ee/0x58a1
[ 9520.382059] btrfs_direct_IO+0x25a/0x6d0 [btrfs]
[ 9520.382321] generic_file_direct_write+0x11e/0x220
[ 9520.382623] btrfs_file_write_iter+0x472/0xac0 [btrfs]
[ 9520.382904] aio_write+0x25c/0x360
[ 9520.383172] io_submit_one+0xaa0/0xdc0
[ 9520.383416] __se_sys_io_submit+0xfa/0x2f0
[ 9520.383678] __x64_sys_io_submit+0x43/0x50
[ 9520.383927] do_syscall_64+0x7d/0x240
[ 9520.384165] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 9520.384439]
[ 9520.384610] The buggy address belongs to the object at ffff8800b7ada500
which belongs to the cache btrfs_free_space of size 72
[ 9520.385175] The buggy address is located 0 bytes inside of
72-byte region [ffff8800b7ada500, ffff8800b7ada548)
[ 9520.385691] The buggy address belongs to the page:
[ 9520.385957] page:ffffea0002deb680 count:1 mapcount:0 mapping:ffff880108a1d700 index:0x0 compound_mapcount: 0
[ 9520.388030] flags: 0x8100(slab|head)
[ 9520.388281] raw: 0000000000008100 ffffea0002deb608 ffffea0002728808 ffff880108a1d700
[ 9520.388722] raw: 0000000000000000 0000000000130013 00000001ffffffff 0000000000000000
[ 9520.389169] page dumped because: kasan: bad access detected
[ 9520.389473]
[ 9520.389658] Memory state around the buggy address:
[ 9520.389943] ffff8800b7ada400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.390368] ffff8800b7ada480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.390796] >ffff8800b7ada500: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc
[ 9520.391223] ^
[ 9520.391461] ffff8800b7ada580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.391885] ffff8800b7ada600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.392313] ==================================================================
[ 9520.392772] BTRFS critical (device vdc): entry offset 2258497536, bytes 131072, bitmap no
[ 9520.393247] BUG: unable to handle kernel NULL pointer dereference at 0000000000000011
[ 9520.393705] PGD 800000010dbab067 P4D 800000010dbab067 PUD 107551067 PMD 0
[ 9520.394059] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 9520.394378] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G B L 4.19.0-rc8-nbor #555
[ 9520.394858] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 9520.395350] RIP: 0010:rb_next+0x3c/0x90
[ 9520.396461] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292
[ 9520.396762] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c
[ 9520.397115] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011
[ 9520.397468] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc
[ 9520.397821] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000
[ 9520.398188] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000
[ 9520.398555] FS: 0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000
[ 9520.399007] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9520.399335] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0
[ 9520.399679] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 9520.400023] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 9520.400400] Call Trace:
[ 9520.400648] btrfs_dump_free_space+0x146/0x160 [btrfs]
[ 9520.400974] dump_space_info+0x2cd/0x310 [btrfs]
[ 9520.401287] btrfs_reserve_extent+0x1ee/0x1f0 [btrfs]
[ 9520.401609] __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs]
[ 9520.401952] ? btrfs_update_time+0x180/0x180 [btrfs]
[ 9520.402232] ? _raw_spin_unlock+0x27/0x40
[ 9520.402522] ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs]
[ 9520.402882] btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs]
[ 9520.403261] cache_save_setup+0x42e/0x580 [btrfs]
[ 9520.403570] ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs]
[ 9520.403871] ? lock_downgrade+0x2f0/0x2f0
[ 9520.404161] ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs]
[ 9520.404481] ? kasan_check_read+0x11/0x20
[ 9520.404732] ? do_raw_spin_unlock+0xa8/0x140
[ 9520.405026] btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs]
[ 9520.405375] ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs]
[ 9520.405694] ? do_raw_spin_unlock+0xa8/0x140
[ 9520.405958] ? _raw_spin_unlock+0x27/0x40
[ 9520.406243] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.406574] commit_cowonly_roots+0x4b9/0x610 [btrfs]
[ 9520.406899] ? commit_fs_roots+0x350/0x350 [btrfs]
[ 9520.407253] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.407589] btrfs_commit_transaction+0x5e5/0x10e0 [btrfs]
[ 9520.407925] ? btrfs_apply_pending_changes+0x90/0x90 [btrfs]
[ 9520.408262] ? start_transaction+0x168/0x6c0 [btrfs]
[ 9520.408582] transaction_kthread+0x21c/0x240 [btrfs]
[ 9520.408870] kthread+0x1d2/0x1f0
[ 9520.409138] ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs]
[ 9520.409440] ? kthread_park+0xb0/0xb0
[ 9520.409682] ret_from_fork+0x3a/0x50
[ 9520.410508] Dumping ftrace buffer:
[ 9520.410764] (ftrace buffer empty)
[ 9520.411007] CR2: 0000000000000011
[ 9520.411297] ---[ end trace 01a0863445cf360a ]---
[ 9520.411568] RIP: 0010:rb_next+0x3c/0x90
[ 9520.412644] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292
[ 9520.412932] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c
[ 9520.413274] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011
[ 9520.413616] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc
[ 9520.414007] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000
[ 9520.414349] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000
[ 9520.416074] FS: 0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000
[ 9520.416536] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9520.416848] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0
[ 9520.418477] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 9520.418846] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 9520.419204] Kernel panic - not syncing: Fatal exception
[ 9520.419666] Dumping ftrace buffer:
[ 9520.419930] (ftrace buffer empty)
[ 9520.420168] Kernel Offset: disabled
[ 9520.420406] ---[ end Kernel panic - not syncing: Fatal exception ]---
Fix this by acquiring the respective lock before iterating the rbtree.
Reported-by: Nikolay Borisov <nborisov@suse.com>
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
At inode.c:evict_inode_truncate_pages(), when we iterate over the
inode's extent states, we access an extent state record's "state" field
after we unlocked the inode's io tree lock. This can lead to a
use-after-free issue because after we unlock the io tree that extent
state record might have been freed due to being merged into another
adjacent extent state record (a previous inflight bio for a read
operation finished in the meanwhile which unlocked a range in the io
tree and cause a merge of extent state records, as explained in the
comment before the while loop added in commit 6ca0709756710 ("Btrfs: fix
hang during inode eviction due to concurrent readahead")).
Fix this by keeping a copy of the extent state's flags in a local
variable and using it after unlocking the io tree.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201189
Fixes: b9d0b38928e2 ("btrfs: Add handler for invalidate page")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We're getting a lockdep splat because we take the dio_sem under the
log_mutex. What we really need is to protect fsync() from logging an
extent map for an extent we never waited on higher up, so just guard the
whole thing with dio_sem.
======================================================
WARNING: possible circular locking dependency detected
4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411 Not tainted
------------------------------------------------------
aio-dio-invalid/30928 is trying to acquire lock:
0000000092621cfd (&mm->mmap_sem){++++}, at: get_user_pages_unlocked+0x5a/0x1e0
but task is already holding lock:
00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #5 (&ei->dio_sem){++++}:
lock_acquire+0xbd/0x220
down_write+0x51/0xb0
btrfs_log_changed_extents+0x80/0xa40
btrfs_log_inode+0xbaf/0x1000
btrfs_log_inode_parent+0x26f/0xa80
btrfs_log_dentry_safe+0x50/0x70
btrfs_sync_file+0x357/0x540
do_fsync+0x38/0x60
__ia32_sys_fdatasync+0x12/0x20
do_fast_syscall_32+0x9a/0x2f0
entry_SYSENTER_compat+0x84/0x96
-> #4 (&ei->log_mutex){+.+.}:
lock_acquire+0xbd/0x220
__mutex_lock+0x86/0xa10
btrfs_record_unlink_dir+0x2a/0xa0
btrfs_unlink+0x5a/0xc0
vfs_unlink+0xb1/0x1a0
do_unlinkat+0x264/0x2b0
do_fast_syscall_32+0x9a/0x2f0
entry_SYSENTER_compat+0x84/0x96
-> #3 (sb_internal#2){.+.+}:
lock_acquire+0xbd/0x220
__sb_start_write+0x14d/0x230
start_transaction+0x3e6/0x590
btrfs_evict_inode+0x475/0x640
evict+0xbf/0x1b0
btrfs_run_delayed_iputs+0x6c/0x90
cleaner_kthread+0x124/0x1a0
kthread+0x106/0x140
ret_from_fork+0x3a/0x50
-> #2 (&fs_info->cleaner_delayed_iput_mutex){+.+.}:
lock_acquire+0xbd/0x220
__mutex_lock+0x86/0xa10
btrfs_alloc_data_chunk_ondemand+0x197/0x530
btrfs_check_data_free_space+0x4c/0x90
btrfs_delalloc_reserve_space+0x20/0x60
btrfs_page_mkwrite+0x87/0x520
do_page_mkwrite+0x31/0xa0
__handle_mm_fault+0x799/0xb00
handle_mm_fault+0x7c/0xe0
__do_page_fault+0x1d3/0x4a0
async_page_fault+0x1e/0x30
-> #1 (sb_pagefaults){.+.+}:
lock_acquire+0xbd/0x220
__sb_start_write+0x14d/0x230
btrfs_page_mkwrite+0x6a/0x520
do_page_mkwrite+0x31/0xa0
__handle_mm_fault+0x799/0xb00
handle_mm_fault+0x7c/0xe0
__do_page_fault+0x1d3/0x4a0
async_page_fault+0x1e/0x30
-> #0 (&mm->mmap_sem){++++}:
__lock_acquire+0x42e/0x7a0
lock_acquire+0xbd/0x220
down_read+0x48/0xb0
get_user_pages_unlocked+0x5a/0x1e0
get_user_pages_fast+0xa4/0x150
iov_iter_get_pages+0xc3/0x340
do_direct_IO+0xf93/0x1d70
__blockdev_direct_IO+0x32d/0x1c20
btrfs_direct_IO+0x227/0x400
generic_file_direct_write+0xcf/0x180
btrfs_file_write_iter+0x308/0x58c
aio_write+0xf8/0x1d0
io_submit_one+0x3a9/0x620
__ia32_compat_sys_io_submit+0xb2/0x270
do_int80_syscall_32+0x5b/0x1a0
entry_INT80_compat+0x88/0xa0
other info that might help us debug this:
Chain exists of:
&mm->mmap_sem --> &ei->log_mutex --> &ei->dio_sem
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ei->dio_sem);
lock(&ei->log_mutex);
lock(&ei->dio_sem);
lock(&mm->mmap_sem);
*** DEADLOCK ***
1 lock held by aio-dio-invalid/30928:
#0: 00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400
stack backtrace:
CPU: 0 PID: 30928 Comm: aio-dio-invalid Not tainted 4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Call Trace:
dump_stack+0x7c/0xbb
print_circular_bug.isra.37+0x297/0x2a4
check_prev_add.constprop.45+0x781/0x7a0
? __lock_acquire+0x42e/0x7a0
validate_chain.isra.41+0x7f0/0xb00
__lock_acquire+0x42e/0x7a0
lock_acquire+0xbd/0x220
? get_user_pages_unlocked+0x5a/0x1e0
down_read+0x48/0xb0
? get_user_pages_unlocked+0x5a/0x1e0
get_user_pages_unlocked+0x5a/0x1e0
get_user_pages_fast+0xa4/0x150
iov_iter_get_pages+0xc3/0x340
do_direct_IO+0xf93/0x1d70
? __alloc_workqueue_key+0x358/0x490
? __blockdev_direct_IO+0x14b/0x1c20
__blockdev_direct_IO+0x32d/0x1c20
? btrfs_run_delalloc_work+0x40/0x40
? can_nocow_extent+0x490/0x490
? kvm_clock_read+0x1f/0x30
? can_nocow_extent+0x490/0x490
? btrfs_run_delalloc_work+0x40/0x40
btrfs_direct_IO+0x227/0x400
? btrfs_run_delalloc_work+0x40/0x40
generic_file_direct_write+0xcf/0x180
btrfs_file_write_iter+0x308/0x58c
aio_write+0xf8/0x1d0
? kvm_clock_read+0x1f/0x30
? __might_fault+0x3e/0x90
io_submit_one+0x3a9/0x620
? io_submit_one+0xe5/0x620
__ia32_compat_sys_io_submit+0xb2/0x270
do_int80_syscall_32+0x5b/0x1a0
entry_INT80_compat+0x88/0xa0
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
This could result in a really bad case where we do something like
evict
evict_refill_and_join
btrfs_commit_transaction
btrfs_run_delayed_iputs
evict
evict_refill_and_join
btrfs_commit_transaction
... forever
We have plenty of other places where we run delayed iputs that are much
safer, let those do the work.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We were not handling the reserved byte accounting properly for data
references. Metadata was fine, if it errored out the error paths would
free the bytes_reserved count and pin the extent, but it even missed one
of the error cases. So instead move this handling up into
run_one_delayed_ref so we are sure that both cases are properly cleaned
up in case of a transaction abort.
CC: stable@vger.kernel.org # 4.18+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When we insert the file extent once the ordered extent completes we free
the reserved extent reservation as it'll have been migrated to the
bytes_used counter. However if we error out after this step we'll still
clear the reserved extent reservation, resulting in a negative
accounting of the reserved bytes for the block group and space info.
Fix this by only doing the free if we didn't successfully insert a file
extent for this extent.
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
max_extent_size is supposed to be the largest contiguous range for the
space info, and ctl->free_space is the total free space in the block
group. We need to keep track of these separately and _only_ use the
max_free_space if we don't have a max_extent_size, as that means our
original request was too large to search any of the block groups for and
therefore wouldn't have a max_extent_size set.
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We can't use entry->bytes if our entry is a bitmap entry, we need to use
entry->max_extent_size in that case. Fix up all the logic to make this
consistent.
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
If we use up our block group before allocating a new one we'll easily
get a max_extent_size that's set really really low, which will result in
a lot of fragmentation. We need to make sure we're resetting the
max_extent_size when we add a new chunk or add new space.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
My work email is completely useless, switch it to my personal address so
I get emails on a account I actually pay attention to.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
The find_ref_head shouldn't return the first entry even if no exact match
is found. So move the hidden behavior to higher level.
Besides, remove the useless local variables in the btrfs_select_ref_head.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
[ reformat comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When writing out a block group free space cache we can end deadlocking
with ourselves on an extent buffer lock resulting in a warning like the
following:
[245043.379979] WARNING: CPU: 4 PID: 2608 at fs/btrfs/locking.c:251 btrfs_tree_lock+0x1be/0x1d0 [btrfs]
[245043.392792] CPU: 4 PID: 2608 Comm: btrfs-transacti Tainted: G
W I 4.16.8 #1
[245043.395489] RIP: 0010:btrfs_tree_lock+0x1be/0x1d0 [btrfs]
[245043.396791] RSP: 0018:ffffc9000424b840 EFLAGS: 00010246
[245043.398093] RAX: 0000000000000a30 RBX: ffff8807e20a3d20 RCX: 0000000000000001
[245043.399414] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff8807e20a3d20
[245043.400732] RBP: 0000000000000001 R08: ffff88041f39a700 R09: ffff880000000000
[245043.402021] R10: 0000000000000040 R11: ffff8807e20a3d20 R12: ffff8807cb220630
[245043.403296] R13: 0000000000000001 R14: ffff8807cb220628 R15: ffff88041fbdf000
[245043.404780] FS: 0000000000000000(0000) GS:ffff88082fc80000(0000) knlGS:0000000000000000
[245043.406050] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[245043.407321] CR2: 00007fffdbdb9f10 CR3: 0000000001c09005 CR4: 00000000000206e0
[245043.408670] Call Trace:
[245043.409977] btrfs_search_slot+0x761/0xa60 [btrfs]
[245043.411278] btrfs_insert_empty_items+0x62/0xb0 [btrfs]
[245043.412572] btrfs_insert_item+0x5b/0xc0 [btrfs]
[245043.413922] btrfs_create_pending_block_groups+0xfb/0x1e0 [btrfs]
[245043.415216] do_chunk_alloc+0x1e5/0x2a0 [btrfs]
[245043.416487] find_free_extent+0xcd0/0xf60 [btrfs]
[245043.417813] btrfs_reserve_extent+0x96/0x1e0 [btrfs]
[245043.419105] btrfs_alloc_tree_block+0xfb/0x4a0 [btrfs]
[245043.420378] __btrfs_cow_block+0x127/0x550 [btrfs]
[245043.421652] btrfs_cow_block+0xee/0x190 [btrfs]
[245043.422979] btrfs_search_slot+0x227/0xa60 [btrfs]
[245043.424279] ? btrfs_update_inode_item+0x59/0x100 [btrfs]
[245043.425538] ? iput+0x72/0x1e0
[245043.426798] write_one_cache_group.isra.49+0x20/0x90 [btrfs]
[245043.428131] btrfs_start_dirty_block_groups+0x102/0x420 [btrfs]
[245043.429419] btrfs_commit_transaction+0x11b/0x880 [btrfs]
[245043.430712] ? start_transaction+0x8e/0x410 [btrfs]
[245043.432006] transaction_kthread+0x184/0x1a0 [btrfs]
[245043.433341] kthread+0xf0/0x130
[245043.434628] ? btrfs_cleanup_transaction+0x4e0/0x4e0 [btrfs]
[245043.435928] ? kthread_create_worker_on_cpu+0x40/0x40
[245043.437236] ret_from_fork+0x1f/0x30
[245043.441054] ---[ end trace 15abaa2aaf36827f ]---
This is because at write_one_cache_group() when we are COWing a leaf from
the extent tree we end up allocating a new block group (chunk) and,
because we have hit a threshold on the number of bytes reserved for system
chunks, we attempt to finalize the creation of new block groups from the
current transaction, by calling btrfs_create_pending_block_groups().
However here we also need to modify the extent tree in order to insert
a block group item, and if the location for this new block group item
happens to be in the same leaf that we were COWing earlier, we deadlock
since btrfs_search_slot() tries to write lock the extent buffer that we
locked before at write_one_cache_group().
We have already hit similar cases in the past and commit d9a0540a79f8
("Btrfs: fix deadlock when finalizing block group creation") fixed some
of those cases by delaying the creation of pending block groups at the
known specific spots that could lead to a deadlock. This change reworks
that commit to be more generic so that we don't have to add similar logic
to every possible path that can lead to a deadlock. This is done by
making __btrfs_cow_block() disallowing the creation of new block groups
(setting the transaction's can_flush_pending_bgs to false) before it
attempts to allocate a new extent buffer for either the extent, chunk or
device trees, since those are the trees that pending block creation
modifies. Once the new extent buffer is allocated, it allows creation of
pending block groups to happen again.
This change depends on a recent patch from Josef which is not yet in
Linus' tree, named "btrfs: make sure we create all new block groups" in
order to avoid occasional warnings at btrfs_trans_release_chunk_metadata().
Fixes: d9a0540a79f8 ("Btrfs: fix deadlock when finalizing block group creation")
CC: stable@vger.kernel.org # 4.4+
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199753
Link: https://lore.kernel.org/linux-btrfs/CAJtFHUTHna09ST-_EEiyWmDH6gAqS6wa=zMNMBsifj8ABu99cw@mail.gmail.com/
Reported-by: E V <eliventer@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When using the NO_HOLES feature and logging a regular file, we were
expecting that if we find an inline extent, that either its size in RAM
(uncompressed and unenconded) matches the size of the file or if it does
not, that it matches the sector size and it represents compressed data.
This assertion does not cover a case where the length of the inline extent
is smaller than the sector size and also smaller the file's size, such
case is possible through fallocate. Example:
$ mkfs.btrfs -f -O no-holes /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0xb60 0 21" /mnt/foobar
$ xfs_io -c "falloc 40 40" /mnt/foobar
$ xfs_io -c "fsync" /mnt/foobar
In the above example we trigger the assertion because the inline extent's
length is 21 bytes while the file size is 80 bytes. The fallocate() call
merely updated the file's size and did not touch the existing inline
extent, as expected.
So fix this by adjusting the assertion so that an inline extent length
smaller than the file size is valid if the file size is smaller than the
filesystem's sector size.
A test case for fstests follows soon.
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Fixes: a89ca6f24ffe ("Btrfs: fix fsync after truncate when no_holes feature is enabled")
CC: stable@vger.kernel.org # 4.14+
Link: https://lore.kernel.org/linux-btrfs/CAE5jQCfRSBC7n4pUTFJcmHh109=gwyT9mFkCOL+NKfzswmR=_Q@mail.gmail.com/
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
At inode.c:compress_file_range(), under the "free_pages_out" label, we can
end up dereferencing the "pages" pointer when it has a NULL value. This
case happens when "start" has a value of 0 and we fail to allocate memory
for the "pages" pointer. When that happens we jump to the "cont" label and
then enter the "if (start == 0)" branch where we immediately call the
cow_file_range_inline() function. If that function returns 0 (success
creating an inline extent) or an error (like -ENOMEM for example) we jump
to the "free_pages_out" label and then access "pages[i]" leading to a NULL
pointer dereference, since "nr_pages" has a value greater than zero at
that point.
Fix this by setting "nr_pages" to 0 when we fail to allocate memory for
the "pages" pointer.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201119
Fixes: 771ed689d2cd ("Btrfs: Optimize compressed writeback and reads")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Using bool is more suitable than int here, and add the comment about the
return_bigger.
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
The avg_delayed_ref_runtime can be referenced from the transaction
handle.
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
It can be referenced from the transaction handle.
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Since trans is only used for referring to delayed_refs, there is no need
to pass it instead of delayed_refs to btrfs_delayed_ref_lock().
No functional change.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Since trans is only used for referring to delayed_refs, there is no need
to pass it instead of delayed_refs to btrfs_select_ref_head(). No
functional change.
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
There is no reason to put this check in (!qgroup)'s else branch because
if qgroup is null, it will goto out directly. So move it out to reduce
indentation level. No functional change.
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Commit 581c1760415c ("btrfs: Validate child tree block's level and first
key") has made tree block level check mandatory.
So if tree block level doesn't match, we won't get a valid extent
buffer. The extra WARN_ON() check can be removed completely.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
And add one line comment explaining what we're doing for each loop.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Some qgroup trace events like btrfs_qgroup_release_data() and
btrfs_qgroup_free_delayed_ref() can still be triggered even if qgroup is
not enabled.
This is caused by the lack of qgroup status check before calling some
qgroup functions. Thankfully the functions can handle quota disabled
case well and just do nothing for qgroup disabled case.
This patch will do earlier check before triggering related trace events.
And for enabled <-> disabled race case:
1) For enabled->disabled case
Disable will wipe out all qgroups data including reservation and
excl/rfer. Even if we leak some reservation or numbers, it will
still be cleared, so nothing will go wrong.
2) For disabled -> enabled case
Current btrfs_qgroup_release_data() will use extent_io tree to ensure
we won't underflow reservation. And for delayed_ref we use
head->qgroup_reserved to record the reserved space, so in that case
head->qgroup_reserved should be 0 and we won't underflow.
CC: stable@vger.kernel.org # 4.14+
Reported-by: Chris Murphy <lists@colorremedies.com>
Link: https://lore.kernel.org/linux-btrfs/CAJCQCtQau7DtuUUeycCkZ36qjbKuxNzsgqJ7+sJ6W0dK_NLE3w@mail.gmail.com/
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
In a scenario like the following:
mkdir /mnt/A # inode 258
mkdir /mnt/B # inode 259
touch /mnt/B/bar # inode 260
sync
mv /mnt/B/bar /mnt/A/bar
mv -T /mnt/A /mnt/B
fsync /mnt/B/bar
<power fail>
After replaying the log we end up with file bar having 2 hard links, both
with the name 'bar' and one in the directory with inode number 258 and the
other in the directory with inode number 259. Also, we end up with the
directory inode 259 still existing and with the directory inode 258 still
named as 'A', instead of 'B'. In this scenario, file 'bar' should only
have one hard link, located at directory inode 258, the directory inode
259 should not exist anymore and the name for directory inode 258 should
be 'B'.
This incorrect behaviour happens because when attempting to log the old
parents of an inode, we skip any parents that no longer exist. Fix this
by forcing a full commit if an old parent no longer exists.
A test case for fstests follows soon.
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When replaying a log which contains a tmpfile (which necessarily has a
link count of 0) we end up calling inc_nlink(), at
fs/btrfs/tree-log.c:replay_one_buffer(), which produces a warning like
the following:
[195191.943673] WARNING: CPU: 0 PID: 6924 at fs/inode.c:342 inc_nlink+0x33/0x40
[195191.943723] CPU: 0 PID: 6924 Comm: mount Not tainted 4.19.0-rc6-btrfs-next-38 #1
[195191.943724] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
[195191.943726] RIP: 0010:inc_nlink+0x33/0x40
[195191.943728] RSP: 0018:ffffb96e425e3870 EFLAGS: 00010246
[195191.943730] RAX: 0000000000000000 RBX: ffff8c0d1e6af4f0 RCX: 0000000000000006
[195191.943731] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8c0d1e6af4f0
[195191.943731] RBP: 0000000000000097 R08: 0000000000000001 R09: 0000000000000000
[195191.943732] R10: 0000000000000000 R11: 0000000000000000 R12: ffffb96e425e3a60
[195191.943733] R13: ffff8c0d10cff0c8 R14: ffff8c0d0d515348 R15: ffff8c0d78a1b3f8
[195191.943735] FS: 00007f570ee24480(0000) GS:ffff8c0dfb200000(0000) knlGS:0000000000000000
[195191.943736] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[195191.943737] CR2: 00005593286277c8 CR3: 00000000bb8f2006 CR4: 00000000003606f0
[195191.943739] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[195191.943740] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[195191.943741] Call Trace:
[195191.943778] replay_one_buffer+0x797/0x7d0 [btrfs]
[195191.943802] walk_up_log_tree+0x1c1/0x250 [btrfs]
[195191.943809] ? rcu_read_lock_sched_held+0x3f/0x70
[195191.943825] walk_log_tree+0xae/0x1d0 [btrfs]
[195191.943840] btrfs_recover_log_trees+0x1d7/0x4d0 [btrfs]
[195191.943856] ? replay_dir_deletes+0x280/0x280 [btrfs]
[195191.943870] open_ctree+0x1c3b/0x22a0 [btrfs]
[195191.943887] btrfs_mount_root+0x6b4/0x800 [btrfs]
[195191.943894] ? rcu_read_lock_sched_held+0x3f/0x70
[195191.943899] ? pcpu_alloc+0x55b/0x7c0
[195191.943906] ? mount_fs+0x3b/0x140
[195191.943908] mount_fs+0x3b/0x140
[195191.943912] ? __init_waitqueue_head+0x36/0x50
[195191.943916] vfs_kern_mount+0x62/0x160
[195191.943927] btrfs_mount+0x134/0x890 [btrfs]
[195191.943936] ? rcu_read_lock_sched_held+0x3f/0x70
[195191.943938] ? pcpu_alloc+0x55b/0x7c0
[195191.943943] ? mount_fs+0x3b/0x140
[195191.943952] ? btrfs_remount+0x570/0x570 [btrfs]
[195191.943954] mount_fs+0x3b/0x140
[195191.943956] ? __init_waitqueue_head+0x36/0x50
[195191.943960] vfs_kern_mount+0x62/0x160
[195191.943963] do_mount+0x1f9/0xd40
[195191.943967] ? memdup_user+0x4b/0x70
[195191.943971] ksys_mount+0x7e/0xd0
[195191.943974] __x64_sys_mount+0x21/0x30
[195191.943977] do_syscall_64+0x60/0x1b0
[195191.943980] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[195191.943983] RIP: 0033:0x7f570e4e524a
[195191.943986] RSP: 002b:00007ffd83589478 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[195191.943989] RAX: ffffffffffffffda RBX: 0000563f335b2060 RCX: 00007f570e4e524a
[195191.943990] RDX: 0000563f335b2240 RSI: 0000563f335b2280 RDI: 0000563f335b2260
[195191.943992] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000020
[195191.943993] R10: 00000000c0ed0000 R11: 0000000000000206 R12: 0000563f335b2260
[195191.943994] R13: 0000563f335b2240 R14: 0000000000000000 R15: 00000000ffffffff
[195191.944002] irq event stamp: 8688
[195191.944010] hardirqs last enabled at (8687): [<ffffffff9cb004c3>] console_unlock+0x503/0x640
[195191.944012] hardirqs last disabled at (8688): [<ffffffff9ca037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
[195191.944018] softirqs last enabled at (8638): [<ffffffff9cc0a5d1>] __set_page_dirty_nobuffers+0x101/0x150
[195191.944020] softirqs last disabled at (8634): [<ffffffff9cc26bbe>] wb_wakeup_delayed+0x2e/0x60
[195191.944022] ---[ end trace 5d6e873a9a0b811a ]---
This happens because the inode does not have the flag I_LINKABLE set,
which is a runtime only flag, not meant to be persisted, set when the
inode is created through open(2) if the flag O_EXCL is not passed to it.
Except for the warning, there are no other consequences (like corruptions
or metadata inconsistencies).
Since it's pointless to replay a tmpfile as it would be deleted in a
later phase of the log replay procedure (it has a link count of 0), fix
this by not logging tmpfiles and if a tmpfile is found in a log (created
by a kernel without this change), skip the replay of the inode.
A test case for fstests follows soon.
Fixes: 471d557afed1 ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay")
CC: stable@vger.kernel.org # 4.18+
Reported-by: Martin Steigerwald <martin@lichtvoll.de>
Link: https://lore.kernel.org/linux-btrfs/3666619.NTnn27ZJZE@merkaba/
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We don't need it, rsv->size is set once and never changes throughout
its lifetime, so just use that for the reserve size.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
I ran into an issue where there was some reference being held on an
inode that I couldn't track. This assert wasn't triggered, but it at
least rules out we're doing something stupid.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Allocating new chunks modifies both the extent and chunk tree, which can
trigger new chunk allocations. So instead of doing list_for_each_safe,
just do while (!list_empty()) so we make sure we don't exit with other
pending bg's still on our list.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We need to clear the max_extent_size when we clear bits from a bitmap
since it could have been from the range that contains the
max_extent_size.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
If we're allocating a new space cache inode it's likely going to be
under a transaction handle, so we need to use memalloc_nofs_save() in
order to avoid deadlocks, and more importantly lockdep messages that
make xfstests fail.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We want to release the unused reservation we have since it refills the
delayed refs reserve, which will make everything go smoother when
running the delayed refs if we're short on our reservation.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Btrfs's btree locking has two modes, spinning mode and blocking mode,
while searching btree, locking is always acquired in spinning mode and
then converted to blocking mode if necessary, and in some hot paths we may
switch the locking back to spinning mode by btrfs_clear_path_blocking().
When acquiring locks, both of reader and writer need to wait for blocking
readers and writers to complete before doing read_lock()/write_lock().
The problem is that btrfs_clear_path_blocking() needs to switch nodes
in the path to blocking mode at first (by btrfs_set_path_blocking) to
make lockdep happy before doing its actual clearing blocking job.
When switching to blocking mode from spinning mode, it consists of
step 1) bumping up blocking readers counter and
step 2) read_unlock()/write_unlock(),
this has caused serious ping-pong effect if there're a great amount of
concurrent readers/writers, as waiters will be woken up and go to
sleep immediately.
1) Killing this kind of ping-pong results in a big improvement in my 1600k
files creation script,
MNT=/mnt/btrfs
mkfs.btrfs -f /dev/sdf
mount /dev/def $MNT
time fsmark -D 10000 -S0 -n 100000 -s 0 -L 1 -l /tmp/fs_log.txt \
-d $MNT/0 -d $MNT/1 \
-d $MNT/2 -d $MNT/3 \
-d $MNT/4 -d $MNT/5 \
-d $MNT/6 -d $MNT/7 \
-d $MNT/8 -d $MNT/9 \
-d $MNT/10 -d $MNT/11 \
-d $MNT/12 -d $MNT/13 \
-d $MNT/14 -d $MNT/15
w/o patch:
real 2m27.307s
user 0m12.839s
sys 13m42.831s
w/ patch:
real 1m2.273s
user 0m15.802s
sys 8m16.495s
1.1) latency histogram from funclatency[1]
Overall with the patch, there're ~50% less write lock acquisition and
the 95% max latency that write lock takes also reduces to ~100ms from
>500ms.
--------------------------------------------
w/o patch:
--------------------------------------------
Function = btrfs_tree_lock
msecs : count distribution
0 -> 1 : 2385222 |****************************************|
2 -> 3 : 37147 | |
4 -> 7 : 20452 | |
8 -> 15 : 13131 | |
16 -> 31 : 3877 | |
32 -> 63 : 3900 | |
64 -> 127 : 2612 | |
128 -> 255 : 974 | |
256 -> 511 : 165 | |
512 -> 1023 : 13 | |
Function = btrfs_tree_read_lock
msecs : count distribution
0 -> 1 : 6743860 |****************************************|
2 -> 3 : 2146 | |
4 -> 7 : 190 | |
8 -> 15 : 38 | |
16 -> 31 : 4 | |
--------------------------------------------
w/ patch:
--------------------------------------------
Function = btrfs_tree_lock
msecs : count distribution
0 -> 1 : 1318454 |****************************************|
2 -> 3 : 6800 | |
4 -> 7 : 3664 | |
8 -> 15 : 2145 | |
16 -> 31 : 809 | |
32 -> 63 : 219 | |
64 -> 127 : 10 | |
Function = btrfs_tree_read_lock
msecs : count distribution
0 -> 1 : 6854317 |****************************************|
2 -> 3 : 2383 | |
4 -> 7 : 601 | |
8 -> 15 : 92 | |
2) dbench also proves the improvement,
dbench -t 120 -D /mnt/btrfs 16
w/o patch:
Throughput 158.363 MB/sec
w/ patch:
Throughput 449.52 MB/sec
3) xfstests didn't show any additional failures.
One thing to note is that callers may set path->leave_spinning to have
all nodes in the path stay in spinning mode, which means callers are
ready to not sleep before releasing the path, but it won't cause
problems if they don't want to sleep in blocking mode.
[1]: https://github.com/iovisor/bcc/blob/master/tools/funclatency.py
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
The value of blocking_readers is increased only when the lock is taken
for read, no way we can fail the condition with the write lock.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
The replace_wait and bio_counter were mistakenly added to fs_info in
commit c404e0dc2c843b154f ("Btrfs: fix use-after-free in the finishing
procedure of the device replace"), but they logically belong to
fs_info::dev_replace. Besides, bio_counter is a very generic name and is
confusing in bare fs_info context.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
The exit sequence in btrfs_dev_replace_start does not allow to simply
add a label to the right place so the error handling after starting
transaction failure jumps there. Currently there's a lock that pairs
with the unlock in the section, which is unnecessary and only raises
questions. Add a variable to track the locking status and avoid the
extra locking.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Too trivial, the purpose can be simply documented in a comment.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
