forked from Minki/linux
8f9a1fa430
8990 Commits
Author | SHA1 | Message | Date | |
---|---|---|---|---|
Linus Torvalds
|
3e08a95294 |
for-5.8-rc2-tag
-----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAl7yABEACgkQxWXV+ddt WDtGoQ//cBWRRWLlLTRgpaKnY6t8JgVUqNvPJISHHf45cNbOJh0yo8hUuKMW+440 8ovYqtFoZD+JHcHDE2sMueHBFe38rG5eT/zh8j/ruhBzeJcTb3lSYz53d7sfl5kD cIVngPEVlGziDqW2PsWLlyh8ulBGzY3YmS6kAEkyP/6/uhE/B1dq6qn3GUibkbKI dfNjHTLwZVmwnqoxLu8ZE2/hHFbzhl0sm09snsXYSVu13g36+edp0Z+pF0MlKGVk G6YrnZcts8TWwneZ4nogD9f2CMvzMhYDDLyEjsX0Ouhb+Cu2WNxdfrJ2ZbPNU82w EGbo451mIt6Ht8wicEjh27LWLI7YMraF/Ig/ODMdvFBYDbhl4voX2t+4n+p5Czbg AW6Wtg/q5EaaNFqrTsqAAiUn0+R3sMiDWrE0AewcE7syPGqQ2XMwP4la5pZ36rz8 8Vo5KIGo44PIJ1dMwcX+bg3HTtUnBJSxE5fUi0rJ3ZfHKGjLS79VonEeQjh3QD6W 0UlK+jCjo6KZoe33XdVV2hVkHd63ZIlliXWv0LOR+gpmqqgW2b3wf181zTvo/5sI v0fDjstA9caqf68ChPE9jJi7rZPp/AL1yAQGEiNzjKm4U431TeZJl2cpREicMJDg FCDU51t9425h8BFkM4scErX2/53F1SNNNSlAsFBGvgJkx6rTENs= =/eCR -----END PGP SIGNATURE----- Merge tag 'for-5.8-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A number of fixes, located in two areas, one performance fix and one fixup for better integration with another patchset. - bug fixes in nowait aio: - fix snapshot creation hang after nowait-aio was used - fix failure to write to prealloc extent past EOF - don't block when extent range is locked - block group fixes: - relocation failure when scrub runs in parallel - refcount fix when removing fails - fix race between removal and creation - space accounting fixes - reinstante fast path check for log tree at unlink time, fixes performance drop up to 30% in REAIM - kzfree/kfree fixup to ease treewide patchset renaming kzfree" * tag 'for-5.8-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: use kfree() in btrfs_ioctl_get_subvol_info() btrfs: fix RWF_NOWAIT writes blocking on extent locks and waiting for IO btrfs: fix RWF_NOWAIT write not failling when we need to cow btrfs: fix failure of RWF_NOWAIT write into prealloc extent beyond eof btrfs: fix hang on snapshot creation after RWF_NOWAIT write btrfs: check if a log root exists before locking the log_mutex on unlink btrfs: fix bytes_may_use underflow when running balance and scrub in parallel btrfs: fix data block group relocation failure due to concurrent scrub btrfs: fix race between block group removal and block group creation btrfs: fix a block group ref counter leak after failure to remove block group |
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Waiman Long
|
b091f7fede |
btrfs: use kfree() in btrfs_ioctl_get_subvol_info()
In btrfs_ioctl_get_subvol_info(), there is a classic case where kzalloc() was incorrectly paired with kzfree(). According to David Sterba, there isn't any sensitive information in the subvol_info that needs to be cleared before freeing. So kzfree() isn't really needed, use kfree() instead. Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Filipe Manana
|
5dbb75ed69 |
btrfs: fix RWF_NOWAIT writes blocking on extent locks and waiting for IO
A RWF_NOWAIT write is not supposed to wait on filesystem locks that can be
held for a long time or for ongoing IO to complete.
However when calling check_can_nocow(), if the inode has prealloc extents
or has the NOCOW flag set, we can block on extent (file range) locks
through the call to btrfs_lock_and_flush_ordered_range(). Such lock can
take a significant amount of time to be available. For example, a fiemap
task may be running, and iterating through the entire file range checking
all extents and doing backref walking to determine if they are shared,
or a readpage operation may be in progress.
Also at btrfs_lock_and_flush_ordered_range(), called by check_can_nocow(),
after locking the file range we wait for any existing ordered extent that
is in progress to complete. Another operation that can take a significant
amount of time and defeat the purpose of RWF_NOWAIT.
So fix this by trying to lock the file range and if it's currently locked
return -EAGAIN to user space. If we are able to lock the file range without
waiting and there is an ordered extent in the range, return -EAGAIN as
well, instead of waiting for it to complete. Finally, don't bother trying
to lock the snapshot lock of the root when attempting a RWF_NOWAIT write,
as that is only important for buffered writes.
Fixes:
|
||
Filipe Manana
|
260a63395f |
btrfs: fix RWF_NOWAIT write not failling when we need to cow
If we attempt to do a RWF_NOWAIT write against a file range for which we
can only do NOCOW for a part of it, due to the existence of holes or
shared extents for example, we proceed with the write as if it were
possible to NOCOW the whole range.
Example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ touch /mnt/sdj/bar
$ chattr +C /mnt/sdj/bar
$ xfs_io -d -c "pwrite -S 0xab -b 256K 0 256K" /mnt/bar
wrote 262144/262144 bytes at offset 0
256 KiB, 1 ops; 0.0003 sec (694.444 MiB/sec and 2777.7778 ops/sec)
$ xfs_io -c "fpunch 64K 64K" /mnt/bar
$ sync
$ xfs_io -d -c "pwrite -N -V 1 -b 128K -S 0xfe 0 128K" /mnt/bar
wrote 131072/131072 bytes at offset 0
128 KiB, 1 ops; 0.0007 sec (160.051 MiB/sec and 1280.4097 ops/sec)
This last write should fail with -EAGAIN since the file range from 64K to
128K is a hole. On xfs it fails, as expected, but on ext4 it currently
succeeds because apparently it is expensive to check if there are extents
allocated for the whole range, but I'll check with the ext4 people.
Fix the issue by checking if check_can_nocow() returns a number of
NOCOW'able bytes smaller then the requested number of bytes, and if it
does return -EAGAIN.
Fixes:
|
||
Filipe Manana
|
4b1946284d |
btrfs: fix failure of RWF_NOWAIT write into prealloc extent beyond eof
If we attempt to write to prealloc extent located after eof using a
RWF_NOWAIT write, we always fail with -EAGAIN.
We do actually check if we have an allocated extent for the write at
the start of btrfs_file_write_iter() through a call to check_can_nocow(),
but later when we go into the actual direct IO write path we simply
return -EAGAIN if the write starts at or beyond EOF.
Trivial to reproduce:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ touch /mnt/foo
$ chattr +C /mnt/foo
$ xfs_io -d -c "pwrite -S 0xab 0 64K" /mnt/foo
wrote 65536/65536 bytes at offset 0
64 KiB, 16 ops; 0.0004 sec (135.575 MiB/sec and 34707.1584 ops/sec)
$ xfs_io -c "falloc -k 64K 1M" /mnt/foo
$ xfs_io -d -c "pwrite -N -V 1 -S 0xfe -b 64K 64K 64K" /mnt/foo
pwrite: Resource temporarily unavailable
On xfs and ext4 the write succeeds, as expected.
Fix this by removing the wrong check at btrfs_direct_IO().
Fixes:
|
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Filipe Manana
|
f2cb2f39cc |
btrfs: fix hang on snapshot creation after RWF_NOWAIT write
If we do a successful RWF_NOWAIT write we end up locking the snapshot lock
of the inode, through a call to check_can_nocow(), but we never unlock it.
This means the next attempt to create a snapshot on the subvolume will
hang forever.
Trivial reproducer:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ touch /mnt/foobar
$ chattr +C /mnt/foobar
$ xfs_io -d -c "pwrite -S 0xab 0 64K" /mnt/foobar
$ xfs_io -d -c "pwrite -N -V 1 -S 0xfe 0 64K" /mnt/foobar
$ btrfs subvolume snapshot -r /mnt /mnt/snap
--> hangs
Fix this by unlocking the snapshot lock if check_can_nocow() returned
success.
Fixes:
|
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Filipe Manana
|
e7a79811d0 |
btrfs: check if a log root exists before locking the log_mutex on unlink
This brings back an optimization that commit |
||
Filipe Manana
|
6bd335b469 |
btrfs: fix bytes_may_use underflow when running balance and scrub in parallel
When balance and scrub are running in parallel it is possible to end up with an underflow of the bytes_may_use counter of the data space_info object, which triggers a warning like the following: [134243.793196] BTRFS info (device sdc): relocating block group 1104150528 flags data [134243.806891] ------------[ cut here ]------------ [134243.807561] WARNING: CPU: 1 PID: 26884 at fs/btrfs/space-info.h:125 btrfs_add_reserved_bytes+0x1da/0x280 [btrfs] [134243.808819] Modules linked in: btrfs blake2b_generic xor (...) [134243.815779] CPU: 1 PID: 26884 Comm: kworker/u8:8 Tainted: G W 5.6.0-rc7-btrfs-next-58 #5 [134243.816944] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [134243.818389] Workqueue: writeback wb_workfn (flush-btrfs-108483) [134243.819186] RIP: 0010:btrfs_add_reserved_bytes+0x1da/0x280 [btrfs] [134243.819963] Code: 0b f2 85 (...) [134243.822271] RSP: 0018:ffffa4160aae7510 EFLAGS: 00010287 [134243.822929] RAX: 000000000000c000 RBX: ffff96159a8c1000 RCX: 0000000000000000 [134243.823816] RDX: 0000000000008000 RSI: 0000000000000000 RDI: ffff96158067a810 [134243.824742] RBP: ffff96158067a800 R08: 0000000000000001 R09: 0000000000000000 [134243.825636] R10: ffff961501432a40 R11: 0000000000000000 R12: 000000000000c000 [134243.826532] R13: 0000000000000001 R14: ffffffffffff4000 R15: ffff96158067a810 [134243.827432] FS: 0000000000000000(0000) GS:ffff9615baa00000(0000) knlGS:0000000000000000 [134243.828451] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [134243.829184] CR2: 000055bd7e414000 CR3: 00000001077be004 CR4: 00000000003606e0 [134243.830083] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [134243.830975] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [134243.831867] Call Trace: [134243.832211] find_free_extent+0x4a0/0x16c0 [btrfs] [134243.832846] btrfs_reserve_extent+0x91/0x180 [btrfs] [134243.833487] cow_file_range+0x12d/0x490 [btrfs] [134243.834080] fallback_to_cow+0x82/0x1b0 [btrfs] [134243.834689] ? release_extent_buffer+0x121/0x170 [btrfs] [134243.835370] run_delalloc_nocow+0x33f/0xa30 [btrfs] [134243.836032] btrfs_run_delalloc_range+0x1ea/0x6d0 [btrfs] [134243.836725] ? find_lock_delalloc_range+0x221/0x250 [btrfs] [134243.837450] writepage_delalloc+0xe8/0x150 [btrfs] [134243.838059] __extent_writepage+0xe8/0x4c0 [btrfs] [134243.838674] extent_write_cache_pages+0x237/0x530 [btrfs] [134243.839364] extent_writepages+0x44/0xa0 [btrfs] [134243.839946] do_writepages+0x23/0x80 [134243.840401] __writeback_single_inode+0x59/0x700 [134243.841006] writeback_sb_inodes+0x267/0x5f0 [134243.841548] __writeback_inodes_wb+0x87/0xe0 [134243.842091] wb_writeback+0x382/0x590 [134243.842574] ? wb_workfn+0x4a2/0x6c0 [134243.843030] wb_workfn+0x4a2/0x6c0 [134243.843468] process_one_work+0x26d/0x6a0 [134243.843978] worker_thread+0x4f/0x3e0 [134243.844452] ? process_one_work+0x6a0/0x6a0 [134243.844981] kthread+0x103/0x140 [134243.845400] ? kthread_create_worker_on_cpu+0x70/0x70 [134243.846030] ret_from_fork+0x3a/0x50 [134243.846494] irq event stamp: 0 [134243.846892] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [134243.847682] hardirqs last disabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020 [134243.848687] softirqs last enabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020 [134243.849913] softirqs last disabled at (0): [<0000000000000000>] 0x0 [134243.850698] ---[ end trace bd7c03622e0b0a96 ]--- [134243.851335] ------------[ cut here ]------------ When relocating a data block group, for each extent allocated in the block group we preallocate another extent with the same size for the data relocation inode (we do it at prealloc_file_extent_cluster()). We reserve space by calling btrfs_check_data_free_space(), which ends up incrementing the data space_info's bytes_may_use counter, and then call btrfs_prealloc_file_range() to allocate the extent, which always decrements the bytes_may_use counter by the same amount. The expectation is that writeback of the data relocation inode always follows a NOCOW path, by writing into the preallocated extents. However, when starting writeback we might end up falling back into the COW path, because the block group that contains the preallocated extent was turned into RO mode by a scrub running in parallel. The COW path then calls the extent allocator which ends up calling btrfs_add_reserved_bytes(), and this function decrements the bytes_may_use counter of the data space_info object by an amount corresponding to the size of the allocated extent, despite we haven't previously incremented it. When the counter currently has a value smaller then the allocated extent we reset the counter to 0 and emit a warning, otherwise we just decrement it and slowly mess up with this counter which is crucial for space reservation, the end result can be granting reserved space to tasks when there isn't really enough free space, and having the tasks fail later in critical places where error handling consists of a transaction abort or hitting a BUG_ON(). Fix this by making sure that if we fallback to the COW path for a data relocation inode, we increment the bytes_may_use counter of the data space_info object. The COW path will then decrement it at btrfs_add_reserved_bytes() on success or through its error handling part by a call to extent_clear_unlock_delalloc() (which ends up calling btrfs_clear_delalloc_extent() that does the decrement operation) in case of an error. Test case btrfs/061 from fstests could sporadically trigger this. 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> |
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Filipe Manana
|
432cd2a10f |
btrfs: fix data block group relocation failure due to concurrent scrub
When running relocation of a data block group while scrub is running in parallel, it is possible that the relocation will fail and abort the current transaction with an -EINVAL error: [134243.988595] BTRFS info (device sdc): found 14 extents, stage: move data extents [134243.999871] ------------[ cut here ]------------ [134244.000741] BTRFS: Transaction aborted (error -22) [134244.001692] WARNING: CPU: 0 PID: 26954 at fs/btrfs/ctree.c:1071 __btrfs_cow_block+0x6a7/0x790 [btrfs] [134244.003380] Modules linked in: btrfs blake2b_generic xor raid6_pq (...) [134244.012577] CPU: 0 PID: 26954 Comm: btrfs Tainted: G W 5.6.0-rc7-btrfs-next-58 #5 [134244.014162] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [134244.016184] RIP: 0010:__btrfs_cow_block+0x6a7/0x790 [btrfs] [134244.017151] Code: 48 c7 c7 (...) [134244.020549] RSP: 0018:ffffa41607863888 EFLAGS: 00010286 [134244.021515] RAX: 0000000000000000 RBX: ffff9614bdfe09c8 RCX: 0000000000000000 [134244.022822] RDX: 0000000000000001 RSI: ffffffffb3d63980 RDI: 0000000000000001 [134244.024124] RBP: ffff961589e8c000 R08: 0000000000000000 R09: 0000000000000001 [134244.025424] R10: ffffffffc0ae5955 R11: 0000000000000000 R12: ffff9614bd530d08 [134244.026725] R13: ffff9614ced41b88 R14: ffff9614bdfe2a48 R15: 0000000000000000 [134244.028024] FS: 00007f29b63c08c0(0000) GS:ffff9615ba600000(0000) knlGS:0000000000000000 [134244.029491] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [134244.030560] CR2: 00007f4eb339b000 CR3: 0000000130d6e006 CR4: 00000000003606f0 [134244.031997] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [134244.033153] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [134244.034484] Call Trace: [134244.034984] btrfs_cow_block+0x12b/0x2b0 [btrfs] [134244.035859] do_relocation+0x30b/0x790 [btrfs] [134244.036681] ? do_raw_spin_unlock+0x49/0xc0 [134244.037460] ? _raw_spin_unlock+0x29/0x40 [134244.038235] relocate_tree_blocks+0x37b/0x730 [btrfs] [134244.039245] relocate_block_group+0x388/0x770 [btrfs] [134244.040228] btrfs_relocate_block_group+0x161/0x2e0 [btrfs] [134244.041323] btrfs_relocate_chunk+0x36/0x110 [btrfs] [134244.041345] btrfs_balance+0xc06/0x1860 [btrfs] [134244.043382] ? btrfs_ioctl_balance+0x27c/0x310 [btrfs] [134244.045586] btrfs_ioctl_balance+0x1ed/0x310 [btrfs] [134244.045611] btrfs_ioctl+0x1880/0x3760 [btrfs] [134244.049043] ? do_raw_spin_unlock+0x49/0xc0 [134244.049838] ? _raw_spin_unlock+0x29/0x40 [134244.050587] ? __handle_mm_fault+0x11b3/0x14b0 [134244.051417] ? ksys_ioctl+0x92/0xb0 [134244.052070] ksys_ioctl+0x92/0xb0 [134244.052701] ? trace_hardirqs_off_thunk+0x1a/0x1c [134244.053511] __x64_sys_ioctl+0x16/0x20 [134244.054206] do_syscall_64+0x5c/0x280 [134244.054891] entry_SYSCALL_64_after_hwframe+0x49/0xbe [134244.055819] RIP: 0033:0x7f29b51c9dd7 [134244.056491] Code: 00 00 00 (...) [134244.059767] RSP: 002b:00007ffcccc1dd08 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [134244.061168] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f29b51c9dd7 [134244.062474] RDX: 00007ffcccc1dda0 RSI: 00000000c4009420 RDI: 0000000000000003 [134244.063771] RBP: 0000000000000003 R08: 00005565cea4b000 R09: 0000000000000000 [134244.065032] R10: 0000000000000541 R11: 0000000000000202 R12: 00007ffcccc2060a [134244.066327] R13: 00007ffcccc1dda0 R14: 0000000000000002 R15: 00007ffcccc1dec0 [134244.067626] irq event stamp: 0 [134244.068202] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [134244.069351] hardirqs last disabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020 [134244.070909] softirqs last enabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020 [134244.072392] softirqs last disabled at (0): [<0000000000000000>] 0x0 [134244.073432] ---[ end trace bd7c03622e0b0a99 ]--- The -EINVAL error comes from the following chain of function calls: __btrfs_cow_block() <-- aborts the transaction btrfs_reloc_cow_block() replace_file_extents() get_new_location() <-- returns -EINVAL When relocating a data block group, for each allocated extent of the block group, we preallocate another extent (at prealloc_file_extent_cluster()), associated with the data relocation inode, and then dirty all its pages. These preallocated extents have, and must have, the same size that extents from the data block group being relocated have. Later before we start the relocation stage that updates pointers (bytenr field of file extent items) to point to the the new extents, we trigger writeback for the data relocation inode. The expectation is that writeback will write the pages to the previously preallocated extents, that it follows the NOCOW path. That is generally the case, however, if a scrub is running it may have turned the block group that contains those extents into RO mode, in which case writeback falls back to the COW path. However in the COW path instead of allocating exactly one extent with the expected size, the allocator may end up allocating several smaller extents due to free space fragmentation - because we tell it at cow_file_range() that the minimum allocation size can match the filesystem's sector size. This later breaks the relocation's expectation that an extent associated to a file extent item in the data relocation inode has the same size as the respective extent pointed by a file extent item in another tree - in this case the extent to which the relocation inode poins to is smaller, causing relocation.c:get_new_location() to return -EINVAL. For example, if we are relocating a data block group X that has a logical address of X and the block group has an extent allocated at the logical address X + 128KiB with a size of 64KiB: 1) At prealloc_file_extent_cluster() we allocate an extent for the data relocation inode with a size of 64KiB and associate it to the file offset 128KiB (X + 128KiB - X) of the data relocation inode. This preallocated extent was allocated at block group Z; 2) A scrub running in parallel turns block group Z into RO mode and starts scrubing its extents; 3) Relocation triggers writeback for the data relocation inode; 4) When running delalloc (btrfs_run_delalloc_range()), we try first the NOCOW path because the data relocation inode has BTRFS_INODE_PREALLOC set in its flags. However, because block group Z is in RO mode, the NOCOW path (run_delalloc_nocow()) falls back into the COW path, by calling cow_file_range(); 5) At cow_file_range(), in the first iteration of the while loop we call btrfs_reserve_extent() to allocate a 64KiB extent and pass it a minimum allocation size of 4KiB (fs_info->sectorsize). Due to free space fragmentation, btrfs_reserve_extent() ends up allocating two extents of 32KiB each, each one on a different iteration of that while loop; 6) Writeback of the data relocation inode completes; 7) Relocation proceeds and ends up at relocation.c:replace_file_extents(), with a leaf which has a file extent item that points to the data extent from block group X, that has a logical address (bytenr) of X + 128KiB and a size of 64KiB. Then it calls get_new_location(), which does a lookup in the data relocation tree for a file extent item starting at offset 128KiB (X + 128KiB - X) and belonging to the data relocation inode. It finds a corresponding file extent item, however that item points to an extent that has a size of 32KiB, which doesn't match the expected size of 64KiB, resuling in -EINVAL being returned from this function and propagated up to __btrfs_cow_block(), which aborts the current transaction. To fix this make sure that at cow_file_range() when we call the allocator we pass it a minimum allocation size corresponding the desired extent size if the inode belongs to the data relocation tree, otherwise pass it the filesystem's sector size as the minimum allocation size. 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> |
||
Filipe Manana
|
ffcb9d4457 |
btrfs: fix race between block group removal and block group creation
There is a race between block group removal and block group creation
when the removal is completed by a task running fitrim or scrub. When
this happens we end up failing the block group creation with an error
-EEXIST since we attempt to insert a duplicate block group item key
in the extent tree. That results in a transaction abort.
The race happens like this:
1) Task A is doing a fitrim, and at btrfs_trim_block_group() it freezes
block group X with btrfs_freeze_block_group() (until very recently
that was named btrfs_get_block_group_trimming());
2) Task B starts removing block group X, either because it's now unused
or due to relocation for example. So at btrfs_remove_block_group(),
while holding the chunk mutex and the block group's lock, it sets
the 'removed' flag of the block group and it sets the local variable
'remove_em' to false, because the block group is currently frozen
(its 'frozen' counter is > 0, until very recently this counter was
named 'trimming');
3) Task B unlocks the block group and the chunk mutex;
4) Task A is done trimming the block group and unfreezes the block group
by calling btrfs_unfreeze_block_group() (until very recently this was
named btrfs_put_block_group_trimming()). In this function we lock the
block group and set the local variable 'cleanup' to true because we
were able to decrement the block group's 'frozen' counter down to 0 and
the flag 'removed' is set in the block group.
Since 'cleanup' is set to true, it locks the chunk mutex and removes
the extent mapping representing the block group from the mapping tree;
5) Task C allocates a new block group Y and it picks up the logical address
that block group X had as the logical address for Y, because X was the
block group with the highest logical address and now the second block
group with the highest logical address, the last in the fs mapping tree,
ends at an offset corresponding to block group X's logical address (this
logical address selection is done at volumes.c:find_next_chunk()).
At this point the new block group Y does not have yet its item added
to the extent tree (nor the corresponding device extent items and
chunk item in the device and chunk trees). The new group Y is added to
the list of pending block groups in the transaction handle;
6) Before task B proceeds to removing the block group item for block
group X from the extent tree, which has a key matching:
(X logical offset, BTRFS_BLOCK_GROUP_ITEM_KEY, length)
task C while ending its transaction handle calls
btrfs_create_pending_block_groups(), which finds block group Y and
tries to insert the block group item for Y into the exten tree, which
fails with -EEXIST since logical offset is the same that X had and
task B hasn't yet deleted the key from the extent tree.
This failure results in a transaction abort, producing a stack like
the following:
------------[ cut here ]------------
BTRFS: Transaction aborted (error -17)
WARNING: CPU: 2 PID: 19736 at fs/btrfs/block-group.c:2074 btrfs_create_pending_block_groups+0x1eb/0x260 [btrfs]
Modules linked in: btrfs blake2b_generic xor raid6_pq (...)
CPU: 2 PID: 19736 Comm: fsstress Tainted: G W 5.6.0-rc7-btrfs-next-58 #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:btrfs_create_pending_block_groups+0x1eb/0x260 [btrfs]
Code: ff ff ff 48 8b 55 50 f0 48 (...)
RSP: 0018:ffffa4160a1c7d58 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff961581909d98 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffffb3d63990 RDI: 0000000000000001
RBP: ffff9614f3356a58 R08: 0000000000000000 R09: 0000000000000001
R10: ffff9615b65b0040 R11: 0000000000000000 R12: ffff961581909c10
R13: ffff9615b0c32000 R14: ffff9614f3356ab0 R15: ffff9614be779000
FS: 00007f2ce2841e80(0000) GS:ffff9615bae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555f18780000 CR3: 0000000131d34005 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
btrfs_start_dirty_block_groups+0x398/0x4e0 [btrfs]
btrfs_commit_transaction+0xd0/0xc50 [btrfs]
? btrfs_attach_transaction_barrier+0x1e/0x50 [btrfs]
? __ia32_sys_fdatasync+0x20/0x20
iterate_supers+0xdb/0x180
ksys_sync+0x60/0xb0
__ia32_sys_sync+0xa/0x10
do_syscall_64+0x5c/0x280
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f2ce1d4d5b7
Code: 83 c4 08 48 3d 01 (...)
RSP: 002b:00007ffd8b558c58 EFLAGS: 00000202 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 000000000000002c RCX: 00007f2ce1d4d5b7
RDX: 00000000ffffffff RSI: 00000000186ba07b RDI: 000000000000002c
RBP: 0000555f17b9e520 R08: 0000000000000012 R09: 000000000000ce00
R10: 0000000000000078 R11: 0000000000000202 R12: 0000000000000032
R13: 0000000051eb851f R14: 00007ffd8b558cd0 R15: 0000555f1798ec20
irq event stamp: 0
hardirqs last enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020
softirqs last enabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace bd7c03622e0b0a9c ]---
Fix this simply by making btrfs_remove_block_group() remove the block
group's item from the extent tree before it flags the block group as
removed. Also make the free space deletion from the free space tree
before flagging the block group as removed, to avoid a similar race
with adding and removing free space entries for the free space tree.
Fixes:
|
||
Filipe Manana
|
9fecd13202 |
btrfs: fix a block group ref counter leak after failure to remove block group
When removing a block group, if we fail to delete the block group's item
from the extent tree, we jump to the 'out' label and end up decrementing
the block group's reference count once only (by 1), resulting in a counter
leak because the block group at that point was already removed from the
block group cache rbtree - so we have to decrement the reference count
twice, once for the rbtree and once for our lookup at the start of the
function.
There is a second bug where if removing the free space tree entries (the
call to remove_block_group_free_space()) fails we end up jumping to the
'out_put_group' label but end up decrementing the reference count only
once, when we should have done it twice, since we have already removed
the block group from the block group cache rbtree. This happens because
the reference count decrement for the rbtree reference happens after
attempting to remove the free space tree entries, which is far away from
the place where we remove the block group from the rbtree.
To make things less error prone, decrement the reference count for the
rbtree immediately after removing the block group from it. This also
eleminates the need for two different exit labels on error, renaming
'out_put_label' to just 'out' and removing the old 'out'.
Fixes:
|
||
Linus Torvalds
|
9d645db853 |
for-5.8-part2-tag
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Merge tag 'for-5.8-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"This reverts the direct io port to iomap infrastructure of btrfs
merged in the first pull request. We found problems in invalidate page
that don't seem to be fixable as regressions or without changing iomap
code that would not affect other filesystems.
There are four reverts in total, but three of them are followup
cleanups needed to revert
|
||
David Sterba
|
55e20bd12a |
Revert "btrfs: switch to iomap_dio_rw() for dio"
This reverts commit
|
||
David Sterba
|
8e0fa5d7b3 |
Revert "btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK"
This reverts commit
|
||
David Sterba
|
f4c48b4408 |
Revert "btrfs: split btrfs_direct_IO to read and write part"
This reverts commit
|
||
Linus Torvalds
|
0b166a57e6 |
A lot of bug fixes and cleanups for ext4, including:
* Fix performance problems found in dioread_nolock now that it is the default, caused by transaction leaks. * Clean up fiemap handling in ext4 * Clean up and refactor multiple block allocator (mballoc) code * Fix a problem with mballoc with a smaller file systems running out of blocks because they couldn't properly use blocks that had been reserved by inode preallocation. * Fixed a race in ext4_sync_parent() versus rename() * Simplify the error handling in the extent manipulation code * Make sure all metadata I/O errors are felected to ext4_ext_dirty()'s and ext4_make_inode_dirty()'s callers. * Avoid passing an error pointer to brelse in ext4_xattr_set() * Fix race which could result to freeing an inode on the dirty last in data=journal mode. * Fix refcount handling if ext4_iget() fails * Fix a crash in generic/019 caused by a corrupted extent node -----BEGIN PGP SIGNATURE----- iQEyBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAl7Ze8kACgkQ8vlZVpUN gaNChAf4xn0ytFSrweI/S2Sp05G/2L/ocZ2TZZk2ZdGeN1E+ABdSIv/zIF9zuFgZ /pY/C+fyEZWt4E3FlNO8gJzoEedkzMCMnUhSIfI+wZbcclyTOSNMJtnrnJKAEtVH HOvGZJmg357jy407RCGhZpJ773nwU2xhBTr5OFxvSf9mt/vzebxIOnw5D7HPlC1V Fgm6Du8q+tRrPsyjv1Yu4pUEVXMJ7qUcvt326AXVM3kCZO1Aa5GrURX0w3J4mzW1 tc1tKmtbLcVVYTo9CwHXhk/edbxrhAydSP2iACand3tK6IJuI6j9x+bBJnxXitnr vsxsfTYMG18+2SxrJ9LwmagqmrRq =HMTs -----END PGP SIGNATURE----- Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "A lot of bug fixes and cleanups for ext4, including: - Fix performance problems found in dioread_nolock now that it is the default, caused by transaction leaks. - Clean up fiemap handling in ext4 - Clean up and refactor multiple block allocator (mballoc) code - Fix a problem with mballoc with a smaller file systems running out of blocks because they couldn't properly use blocks that had been reserved by inode preallocation. - Fixed a race in ext4_sync_parent() versus rename() - Simplify the error handling in the extent manipulation code - Make sure all metadata I/O errors are felected to ext4_ext_dirty()'s and ext4_make_inode_dirty()'s callers. - Avoid passing an error pointer to brelse in ext4_xattr_set() - Fix race which could result to freeing an inode on the dirty last in data=journal mode. - Fix refcount handling if ext4_iget() fails - Fix a crash in generic/019 caused by a corrupted extent node" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (58 commits) ext4: avoid unnecessary transaction starts during writeback ext4: don't block for O_DIRECT if IOCB_NOWAIT is set ext4: remove the access_ok() check in ext4_ioctl_get_es_cache fs: remove the access_ok() check in ioctl_fiemap fs: handle FIEMAP_FLAG_SYNC in fiemap_prep fs: move fiemap range validation into the file systems instances iomap: fix the iomap_fiemap prototype fs: move the fiemap definitions out of fs.h fs: mark __generic_block_fiemap static ext4: remove the call to fiemap_check_flags in ext4_fiemap ext4: split _ext4_fiemap ext4: fix fiemap size checks for bitmap files ext4: fix EXT4_MAX_LOGICAL_BLOCK macro add comment for ext4_dir_entry_2 file_type member jbd2: avoid leaking transaction credits when unreserving handle ext4: drop ext4_journal_free_reserved() ext4: mballoc: use lock for checking free blocks while retrying ext4: mballoc: refactor ext4_mb_good_group() ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling ext4: mballoc: refactor ext4_mb_discard_preallocations() ... |
||
Christoph Hellwig
|
45dd052e67 |
fs: handle FIEMAP_FLAG_SYNC in fiemap_prep
By moving FIEMAP_FLAG_SYNC handling to fiemap_prep we ensure it is handled once instead of duplicated, but can still be done under fs locks, like xfs/iomap intended with its duplicate handling. Also make sure the error value of filemap_write_and_wait is propagated to user space. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Link: https://lore.kernel.org/r/20200523073016.2944131-8-hch@lst.de Signed-off-by: Theodore Ts'o <tytso@mit.edu> |
||
Christoph Hellwig
|
cddf8a2c4a |
fs: move fiemap range validation into the file systems instances
Replace fiemap_check_flags with a fiemap_prep helper that also takes the inode and mapped range, and performs the sanity check and truncation previously done in fiemap_check_range. This way the validation is inside the file system itself and thus properly works for the stacked overlayfs case as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Link: https://lore.kernel.org/r/20200523073016.2944131-7-hch@lst.de Signed-off-by: Theodore Ts'o <tytso@mit.edu> |
||
Christoph Hellwig
|
10c5db2864 |
fs: move the fiemap definitions out of fs.h
No need to pull the fiemap definitions into almost every file in the kernel build. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Link: https://lore.kernel.org/r/20200523073016.2944131-5-hch@lst.de Signed-off-by: Theodore Ts'o <tytso@mit.edu> |
||
Linus Torvalds
|
f3cdc8ae11 |
for-5.8-tag
-----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAl7U50AACgkQxWXV+ddt WDtK1g//RXeNsTguYQr1N9R5eUPThjLEI0+4J0l4SYfCPU8Ou3C7nqpOEJJQgm8F ezZE+16cWi9U5uGueOc+w0rfyz4AuIXKgzoz+c0/GG2+yV5jp6DsAMbWqojAb96L V/N3HxEzR66jqwgVUBE/x5okb2SyY7//B1l/O0amc66XDO7KTMImpIwThere6zWZ o2SNpYpHAPQeUYJQx8h+FAW3w1CxrCZmnifazU9Jqe9J7QeQLg7rbUlJDV38jySm ZOA8ohKN9U1gPZy+dTU3kdyyuBIq1etkIaSPJANyTo5TczPKiC0IMg75cXtS4ae/ NSxhccMpSIjVMcIHARzSFGYKNP3sGNRsmaTUg/2Cx/9GoHOhYMiCAVc8qtBBpwJO UI0siexrCe64RuTBMRRc128GdFv7IjmSImcdi8xaR62bCcUiNdEa3zvjRe/9tOEH ET7Z85oBnKpSzpC3MdhSUU4dtHY5XLawP8z3oUU1VSzSWM2DVjlHf79/VzbOfp18 miCVpt94lCn/gUX7el6qcnbuvMAjDyeC6HmfD+TwzQgGwyV6TLgKN9lRXeH/Oy6/ VgjGQSavGHMll3zIGURmrBCXKudjJg0J+IP4wN1TimmSEMfwKH+7tnekQd8y5qlF eXEIqlWNykKeDzEnmV9QJy+/cV83hVWM/mUslcTx39tLN/3B/Us= =qTt8 -----END PGP SIGNATURE----- Merge tag 'for-5.8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "Highlights: - speedup dead root detection during orphan cleanup, eg. when there are many deleted subvolumes waiting to be cleaned, the trees are now looked up in radix tree instead of a O(N^2) search - snapshot creation with inherited qgroup will mark the qgroup inconsistent, requires a rescan - send will emit file capabilities after chown, this produces a stream that does not need postprocessing to set the capabilities again - direct io ported to iomap infrastructure, cleaned up and simplified code, notably removing last use of struct buffer_head in btrfs code Core changes: - factor out backreference iteration, to be used by ordinary backreferences and relocation code - improved global block reserve utilization * better logic to serialize requests * increased maximum available for unlink * improved handling on large pages (64K) - direct io cleanups and fixes * simplify layering, where cloned bios were unnecessarily created for some cases * error handling fixes (submit, endio) * remove repair worker thread, used to avoid deadlocks during repair - refactored block group reading code, preparatory work for new type of block group storage that should improve mount time on large filesystems Cleanups: - cleaned up (and slightly sped up) set/get helpers for metadata data structure members - root bit REF_COWS got renamed to SHAREABLE to reflect the that the blocks of the tree get shared either among subvolumes or with the relocation trees Fixes: - when subvolume deletion fails due to ENOSPC, the filesystem is not turned read-only - device scan deals with devices from other filesystems that changed ownership due to overwrite (mkfs) - fix a race between scrub and block group removal/allocation - fix long standing bug of a runaway balance operation, printing the same line to the syslog, caused by a stale status bit on a reloc tree that prevented progress - fix corrupt log due to concurrent fsync of inodes with shared extents - fix space underflow for NODATACOW and buffered writes when it for some reason needs to fallback to COW mode" * tag 'for-5.8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (133 commits) btrfs: fix space_info bytes_may_use underflow during space cache writeout btrfs: fix space_info bytes_may_use underflow after nocow buffered write btrfs: fix wrong file range cleanup after an error filling dealloc range btrfs: remove redundant local variable in read_block_for_search btrfs: open code key_search btrfs: split btrfs_direct_IO to read and write part btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK fs: remove dio_end_io() btrfs: switch to iomap_dio_rw() for dio iomap: remove lockdep_assert_held() iomap: add a filesystem hook for direct I/O bio submission fs: export generic_file_buffered_read() btrfs: turn space cache writeout failure messages into debug messages btrfs: include error on messages about failure to write space/inode caches btrfs: remove useless 'fail_unlock' label from btrfs_csum_file_blocks() btrfs: do not ignore error from btrfs_next_leaf() when inserting checksums btrfs: make checksum item extension more efficient btrfs: fix corrupt log due to concurrent fsync of inodes with shared extents btrfs: unexport btrfs_compress_set_level() btrfs: simplify iget helpers ... |
||
Linus Torvalds
|
94709049fb |
Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton: "A few little subsystems and a start of a lot of MM patches. Subsystems affected by this patch series: squashfs, ocfs2, parisc, vfs. With mm subsystems: slab-generic, slub, debug, pagecache, gup, swap, memcg, pagemap, memory-failure, vmalloc, kasan" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits) kasan: move kasan_report() into report.c mm/mm_init.c: report kasan-tag information stored in page->flags ubsan: entirely disable alignment checks under UBSAN_TRAP kasan: fix clang compilation warning due to stack protector x86/mm: remove vmalloc faulting mm: remove vmalloc_sync_(un)mappings() x86/mm/32: implement arch_sync_kernel_mappings() x86/mm/64: implement arch_sync_kernel_mappings() mm/ioremap: track which page-table levels were modified mm/vmalloc: track which page-table levels were modified mm: add functions to track page directory modifications s390: use __vmalloc_node in stack_alloc powerpc: use __vmalloc_node in alloc_vm_stack arm64: use __vmalloc_node in arch_alloc_vmap_stack mm: remove vmalloc_user_node_flags mm: switch the test_vmalloc module to use __vmalloc_node mm: remove __vmalloc_node_flags_caller mm: remove both instances of __vmalloc_node_flags mm: remove the prot argument to __vmalloc_node mm: remove the pgprot argument to __vmalloc ... |
||
Guoqing Jiang
|
d1b89bc042 |
btrfs: use attach/detach_page_private
Since the new pair function is introduced, we can call them to clean the code in btrfs. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Link: http://lkml.kernel.org/r/20200517214718.468-4-guoqing.jiang@cloud.ionos.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Matthew Wilcox (Oracle)
|
ba206a026f |
btrfs: convert from readpages to readahead
Implement the new readahead method in btrfs using the new readahead_page_batch() function. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Link: http://lkml.kernel.org/r/20200414150233.24495-18-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Linus Torvalds
|
e0cd920687 |
Merge branch 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uaccess/access_ok updates from Al Viro: "Removals of trivially pointless access_ok() calls. Note: the fiemap stuff was removed from the series, since they are duplicates with part of ext4 series carried in Ted's tree" * 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vmci_host: get rid of pointless access_ok() hfi1: get rid of pointless access_ok() usb: get rid of pointless access_ok() calls lpfc_debugfs: get rid of pointless access_ok() efi_test: get rid of pointless access_ok() drm_read(): get rid of pointless access_ok() via-pmu: don't bother with access_ok() drivers/crypto/ccp/sev-dev.c: get rid of pointless access_ok() omapfb: get rid of pointless access_ok() calls amifb: get rid of pointless access_ok() calls drivers/fpga/dfl-afu-dma-region.c: get rid of pointless access_ok() drivers/fpga/dfl-fme-pr.c: get rid of pointless access_ok() cm4000_cs.c cmm_ioctl(): get rid of pointless access_ok() nvram: drop useless access_ok() n_hdlc_tty_read(): remove pointless access_ok() tomoyo_write_control(): get rid of pointless access_ok() btrfs_ioctl_send(): don't bother with access_ok() fat_dir_ioctl(): hadn't needed that access_ok() for more than a decade... dlmfs_file_write(): get rid of pointless access_ok() |
||
Filipe Manana
|
2166e5edce |
btrfs: fix space_info bytes_may_use underflow during space cache writeout
We always preallocate a data extent for writing a free space cache, which
causes writeback to always try the nocow path first, since the free space
inode has the prealloc bit set in its flags.
However if the block group that contains the data extent for the space
cache has been turned to RO mode due to a running scrub or balance for
example, we have to fallback to the cow path. In that case once a new data
extent is allocated we end up calling btrfs_add_reserved_bytes(), which
decrements the counter named bytes_may_use from the data space_info object
with the expection that this counter was previously incremented with the
same amount (the size of the data extent).
However when we started writeout of the space cache at cache_save_setup(),
we incremented the value of the bytes_may_use counter through a call to
btrfs_check_data_free_space() and then decremented it through a call to
btrfs_prealloc_file_range_trans() immediately after. So when starting the
writeback if we fallback to cow mode we have to increment the counter
bytes_may_use of the data space_info again to compensate for the extent
allocation done by the cow path.
When this issue happens we are incorrectly decrementing the bytes_may_use
counter and when its current value is smaller then the amount we try to
subtract we end up with the following warning:
------------[ cut here ]------------
WARNING: CPU: 3 PID: 657 at fs/btrfs/space-info.h:115 btrfs_add_reserved_bytes+0x3d6/0x4e0 [btrfs]
Modules linked in: btrfs blake2b_generic xor raid6_pq libcrc32c (...)
CPU: 3 PID: 657 Comm: kworker/u8:7 Tainted: G W 5.6.0-rc7-btrfs-next-58 #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Workqueue: writeback wb_workfn (flush-btrfs-1591)
RIP: 0010:btrfs_add_reserved_bytes+0x3d6/0x4e0 [btrfs]
Code: ff ff 48 (...)
RSP: 0000:ffffa41608f13660 EFLAGS: 00010287
RAX: 0000000000001000 RBX: ffff9615b93ae400 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff9615b96ab410
RBP: fffffffffffee000 R08: 0000000000000001 R09: 0000000000000000
R10: ffff961585e62a40 R11: 0000000000000000 R12: ffff9615b96ab400
R13: ffff9615a1a2a000 R14: 0000000000012000 R15: ffff9615b93ae400
FS: 0000000000000000(0000) GS:ffff9615bb200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cbbc2ae178 CR3: 0000000115794006 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
find_free_extent+0x4a0/0x16c0 [btrfs]
btrfs_reserve_extent+0x91/0x180 [btrfs]
cow_file_range+0x12d/0x490 [btrfs]
btrfs_run_delalloc_range+0x9f/0x6d0 [btrfs]
? find_lock_delalloc_range+0x221/0x250 [btrfs]
writepage_delalloc+0xe8/0x150 [btrfs]
__extent_writepage+0xe8/0x4c0 [btrfs]
extent_write_cache_pages+0x237/0x530 [btrfs]
extent_writepages+0x44/0xa0 [btrfs]
do_writepages+0x23/0x80
__writeback_single_inode+0x59/0x700
writeback_sb_inodes+0x267/0x5f0
__writeback_inodes_wb+0x87/0xe0
wb_writeback+0x382/0x590
? wb_workfn+0x4a2/0x6c0
wb_workfn+0x4a2/0x6c0
process_one_work+0x26d/0x6a0
worker_thread+0x4f/0x3e0
? process_one_work+0x6a0/0x6a0
kthread+0x103/0x140
? kthread_create_worker_on_cpu+0x70/0x70
ret_from_fork+0x3a/0x50
irq event stamp: 0
hardirqs last enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020
softirqs last enabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace bd7c03622e0b0a52 ]---
------------[ cut here ]------------
So fix this by incrementing the bytes_may_use counter of the data
space_info when we fallback to the cow path. If the cow path is successful
the counter is decremented after extent allocation (by
btrfs_add_reserved_bytes()), if it fails it ends up being decremented as
well when clearing the delalloc range (extent_clear_unlock_delalloc()).
This could be triggered sporadically by the test case btrfs/061 from
fstests.
Fixes:
|
||
Filipe Manana
|
467dc47ea9 |
btrfs: fix space_info bytes_may_use underflow after nocow buffered write
When doing a buffered write we always try to reserve data space for it,
even when the file has the NOCOW bit set or the write falls into a file
range covered by a prealloc extent. This is done both because it is
expensive to check if we can do a nocow write (checking if an extent is
shared through reflinks or if there's a hole in the range for example),
and because when writeback starts we might actually need to fallback to
COW mode (for example the block group containing the target extents was
turned into RO mode due to a scrub or balance).
When we are unable to reserve data space we check if we can do a nocow
write, and if we can, we proceed with dirtying the pages and setting up
the range for delalloc. In this case the bytes_may_use counter of the
data space_info object is not incremented, unlike in the case where we
are able to reserve data space (done through btrfs_check_data_free_space()
which calls btrfs_alloc_data_chunk_ondemand()).
Later when running delalloc we attempt to start writeback in nocow mode
but we might revert back to cow mode, for example because in the meanwhile
a block group was turned into RO mode by a scrub or relocation. The cow
path after successfully allocating an extent ends up calling
btrfs_add_reserved_bytes(), which expects the bytes_may_use counter of
the data space_info object to have been incremented before - but we did
not do it when the buffered write started, since there was not enough
available data space. So btrfs_add_reserved_bytes() ends up decrementing
the bytes_may_use counter anyway, and when the counter's current value
is smaller then the size of the allocated extent we get a stack trace
like the following:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 20138 at fs/btrfs/space-info.h:115 btrfs_add_reserved_bytes+0x3d6/0x4e0 [btrfs]
Modules linked in: btrfs blake2b_generic xor raid6_pq libcrc32c (...)
CPU: 0 PID: 20138 Comm: kworker/u8:15 Not tainted 5.6.0-rc7-btrfs-next-58 #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Workqueue: writeback wb_workfn (flush-btrfs-1754)
RIP: 0010:btrfs_add_reserved_bytes+0x3d6/0x4e0 [btrfs]
Code: ff ff 48 (...)
RSP: 0018:ffffbda18a4b3568 EFLAGS: 00010287
RAX: 0000000000000000 RBX: ffff9ca076f5d800 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff9ca068470410
RBP: fffffffffffff000 R08: 0000000000000001 R09: 0000000000000000
R10: ffff9ca079d58040 R11: 0000000000000000 R12: ffff9ca068470400
R13: ffff9ca0408b2000 R14: 0000000000001000 R15: ffff9ca076f5d800
FS: 0000000000000000(0000) GS:ffff9ca07a600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005605dbfe7048 CR3: 0000000138570006 CR4: 00000000003606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
find_free_extent+0x4a0/0x16c0 [btrfs]
btrfs_reserve_extent+0x91/0x180 [btrfs]
cow_file_range+0x12d/0x490 [btrfs]
run_delalloc_nocow+0x341/0xa40 [btrfs]
btrfs_run_delalloc_range+0x1ea/0x6d0 [btrfs]
? find_lock_delalloc_range+0x221/0x250 [btrfs]
writepage_delalloc+0xe8/0x150 [btrfs]
__extent_writepage+0xe8/0x4c0 [btrfs]
extent_write_cache_pages+0x237/0x530 [btrfs]
? btrfs_wq_submit_bio+0x9f/0xc0 [btrfs]
extent_writepages+0x44/0xa0 [btrfs]
do_writepages+0x23/0x80
__writeback_single_inode+0x59/0x700
writeback_sb_inodes+0x267/0x5f0
__writeback_inodes_wb+0x87/0xe0
wb_writeback+0x382/0x590
? wb_workfn+0x4a2/0x6c0
wb_workfn+0x4a2/0x6c0
process_one_work+0x26d/0x6a0
worker_thread+0x4f/0x3e0
? process_one_work+0x6a0/0x6a0
kthread+0x103/0x140
? kthread_create_worker_on_cpu+0x70/0x70
ret_from_fork+0x3a/0x50
irq event stamp: 0
hardirqs last enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<ffffffff94ebdedf>] copy_process+0x74f/0x2020
softirqs last enabled at (0): [<ffffffff94ebdedf>] copy_process+0x74f/0x2020
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace f9f6ef8ec4cd8ec9 ]---
So to fix this, when falling back into cow mode check if space was not
reserved, by testing for the bit EXTENT_NORESERVE in the respective file
range, and if not, increment the bytes_may_use counter for the data
space_info object. Also clear the EXTENT_NORESERVE bit from the range, so
that if the cow path fails it decrements the bytes_may_use counter when
clearing the delalloc range (through the btrfs_clear_delalloc_extent()
callback).
Fixes:
|
||
Filipe Manana
|
e2c8e92d11 |
btrfs: fix wrong file range cleanup after an error filling dealloc range
If an error happens while running dellaloc in COW mode for a range, we can
end up calling extent_clear_unlock_delalloc() for a range that goes beyond
our range's end offset by 1 byte, which affects 1 extra page. This results
in clearing bits and doing page operations (such as a page unlock) outside
our target range.
Fix that by calling extent_clear_unlock_delalloc() with an inclusive end
offset, instead of an exclusive end offset, at cow_file_range().
Fixes:
|
||
Nikolay Borisov
|
213ff4b72a |
btrfs: remove redundant local variable in read_block_for_search
The local 'b' variable is only used to directly read values from passed extent buffer. So eliminate it and directly use the input parameter. Furthermore this shrinks the size of the following functions: ./scripts/bloat-o-meter ctree.orig fs/btrfs/ctree.o add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-73 (-73) Function old new delta read_block_for_search.isra 876 871 -5 push_node_left 1112 1044 -68 Total: Before=50348, After=50275, chg -0.14% Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Nikolay Borisov
|
995e9a166b |
btrfs: open code key_search
This function wraps the optimisation implemented by
|
||
Christoph Hellwig
|
d8f3e73587 |
btrfs: split btrfs_direct_IO to read and write part
The read and write versions don't have anything in common except for the call to iomap_dio_rw. So split this function, and merge each half into its only caller. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Goldwyn Rodrigues
|
5f008163a5 |
btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK
Since we now perform direct reads using i_rwsem, we can remove this inode flag used to co-ordinate unlocked reads. The truncate call takes i_rwsem. This means it is correctly synchronized with concurrent direct reads. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Johannes Thumshirn <jth@kernel.org> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Goldwyn Rodrigues
|
a43a67a2d7 |
btrfs: switch to iomap_dio_rw() for dio
Switch from __blockdev_direct_IO() to iomap_dio_rw(). Rename btrfs_get_blocks_direct() to btrfs_dio_iomap_begin() and use it as iomap_begin() for iomap direct I/O functions. This function allocates and locks all the blocks required for the I/O. btrfs_submit_direct() is used as the submit_io() hook for direct I/O ops. Since we need direct I/O reads to go through iomap_dio_rw(), we change file_operations.read_iter() to a btrfs_file_read_iter() which calls btrfs_direct_IO() for direct reads and falls back to generic_file_buffered_read() for incomplete reads and buffered reads. We don't need address_space.direct_IO() anymore so set it to noop. Similarly, we don't need flags used in __blockdev_direct_IO(). iomap is capable of direct I/O reads from a hole, so we don't need to return -ENOENT. BTRFS direct I/O is now done under i_rwsem, shared in case of reads and exclusive in case of writes. This guards against simultaneous truncates. Use iomap->iomap_end() to check for failed or incomplete direct I/O: - for writes, call __endio_write_update_ordered() - for reads, unlock extents btrfs_dio_data is now hooked in iomap->private and not current->journal_info. It carries the reservation variable and the amount of data submitted, so we can calculate the amount of data to call __endio_write_update_ordered in case of an error. This patch removes last use of struct buffer_head from btrfs. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Filipe Manana
|
bbcd1f4d52 |
btrfs: turn space cache writeout failure messages into debug messages
Since commit
|
||
Filipe Manana
|
2e69a7a60d |
btrfs: include error on messages about failure to write space/inode caches
Currently the error messages logged when we fail to write a free space cache or an inode cache are not very useful as they don't mention what was the error. So include the error number in the messages. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Filipe Manana
|
918cdf4423 |
btrfs: remove useless 'fail_unlock' label from btrfs_csum_file_blocks()
The label 'fail_unlock' is pointless, all it does is to jump to the label 'out', so just remove it. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Filipe Manana
|
7e4a3f7ed5 |
btrfs: do not ignore error from btrfs_next_leaf() when inserting checksums
We are currently treating any non-zero return value from btrfs_next_leaf() the same way, by going to the code that inserts a new checksum item in the tree. However if btrfs_next_leaf() returns an error (a value < 0), we should just stop and return the error, and not behave as if nothing has happened, since in that case we do not have a way to know if there is a next leaf or we are currently at the last leaf already. So fix that by returning the error from btrfs_next_leaf(). Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Filipe Manana
|
cc14600c15 |
btrfs: make checksum item extension more efficient
When we want to add checksums into the checksums tree, or a log tree, we try whenever possible to extend existing checksum items, as this helps reduce amount of metadata space used, since adding a new item uses extra metadata space for a btrfs_item structure (25 bytes). However we have two inefficiencies in the current approach: 1) After finding a checksum item that covers a range with an end offset that matches the start offset of the checksum range we want to insert, we release the search path populated by btrfs_lookup_csum() and then do another COW search on tree with the goal of getting additional space for at least one checksum. Doing this path release and then searching again is a waste of time because very often the leaf already has enough free space for at least one more checksum; 2) After the COW search that guarantees we get free space in the leaf for at least one more checksum, we end up not doing the extension of the previous checksum item, and fallback to insertion of a new checksum item, if the leaf doesn't have an amount of free space larger then the space required for 2 checksums plus one btrfs_item structure - this is pointless for two reasons: a) We want to extend an existing item, so we don't need to account for a btrfs_item structure (25 bytes); b) We made the COW search with an insertion size for 1 single checksum, so if the leaf ends up with a free space amount smaller then 2 checksums plus the size of a btrfs_item structure, we give up on the extension of the existing item and jump to the 'insert' label, where we end up releasing the path and then doing yet another search to insert a new checksum item for a single checksum. Fix these inefficiencies by doing the following: - For case 1), before releasing the path just check if the leaf already has enough space for at least 1 more checksum, and if it does, jump directly to the item extension code, with releasing our current path, which was already COWed by btrfs_lookup_csum(); - For case 2), fix the logic so that for item extension we require only that the leaf has enough free space for 1 checksum, and not a minimum of 2 checksums plus space for a btrfs_item structure. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Filipe Manana
|
e289f03ea7 |
btrfs: fix corrupt log due to concurrent fsync of inodes with shared extents
When we have extents shared amongst different inodes in the same subvolume, if we fsync them in parallel we can end up with checksum items in the log tree that represent ranges which overlap. For example, consider we have inodes A and B, both sharing an extent that covers the logical range from X to X + 64KiB: 1) Task A starts an fsync on inode A; 2) Task B starts an fsync on inode B; 3) Task A calls btrfs_csum_file_blocks(), and the first search in the log tree, through btrfs_lookup_csum(), returns -EFBIG because it finds an existing checksum item that covers the range from X - 64KiB to X; 4) Task A checks that the checksum item has not reached the maximum possible size (MAX_CSUM_ITEMS) and then releases the search path before it does another path search for insertion (through a direct call to btrfs_search_slot()); 5) As soon as task A releases the path and before it does the search for insertion, task B calls btrfs_csum_file_blocks() and gets -EFBIG too, because there is an existing checksum item that has an end offset that matches the start offset (X) of the checksum range we want to log; 6) Task B releases the path; 7) Task A does the path search for insertion (through btrfs_search_slot()) and then verifies that the checksum item that ends at offset X still exists and extends its size to insert the checksums for the range from X to X + 64KiB; 8) Task A releases the path and returns from btrfs_csum_file_blocks(), having inserted the checksums into an existing checksum item that got its size extended. At this point we have one checksum item in the log tree that covers the logical range from X - 64KiB to X + 64KiB; 9) Task B now does a search for insertion using btrfs_search_slot() too, but it finds that the previous checksum item no longer ends at the offset X, it now ends at an of offset X + 64KiB, so it leaves that item untouched. Then it releases the path and calls btrfs_insert_empty_item() that inserts a checksum item with a key offset corresponding to X and a size for inserting a single checksum (4 bytes in case of crc32c). Subsequent iterations end up extending this new checksum item so that it contains the checksums for the range from X to X + 64KiB. So after task B returns from btrfs_csum_file_blocks() we end up with two checksum items in the log tree that have overlapping ranges, one for the range from X - 64KiB to X + 64KiB, and another for the range from X to X + 64KiB. Having checksum items that represent ranges which overlap, regardless of being in the log tree or in the chekcsums tree, can lead to problems where checksums for a file range end up not being found. This type of problem has happened a few times in the past and the following commits fixed them and explain in detail why having checksum items with overlapping ranges is problematic: |
||
Anand Jain
|
adbab6420c |
btrfs: unexport btrfs_compress_set_level()
btrfs_compress_set_level() can be static function in the file compression.c. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
David Sterba
|
0202e83fda |
btrfs: simplify iget helpers
The inode lookup starting at btrfs_iget takes the full location key, while only the objectid is used to match the inode, because the lookup happens inside the given root thus the inode number is unique. The entire location key is properly set up in btrfs_init_locked_inode. Simplify the helpers and pass only inode number, renaming it to 'ino' instead of 'objectid'. This allows to remove temporary variables key, saving some stack space. Signed-off-by: David Sterba <dsterba@suse.com> |
||
David Sterba
|
a820feb546 |
btrfs: open code read_fs_root
After the update to btrfs_get_fs_root, read_fs_root has become trivial wrapper that can be open coded. Signed-off-by: David Sterba <dsterba@suse.com> |
||
David Sterba
|
56e9357a1e |
btrfs: simplify root lookup by id
The main function to lookup a root by its id btrfs_get_fs_root takes the whole key, while only using the objectid. The value of offset is preset to (u64)-1 but not actually used until btrfs_find_root that does the actual search. Switch btrfs_get_fs_root to use only objectid and remove all local variables that existed just for the lookup. The actual key for search is set up in btrfs_get_fs_root, reusing another key variable. Signed-off-by: David Sterba <dsterba@suse.com> |
||
Qu Wenruo
|
1dae7e0e58 |
btrfs: reloc: clear DEAD_RELOC_TREE bit for orphan roots to prevent runaway balance
[BUG] There are several reported runaway balance, that balance is flooding the log with "found X extents" where the X never changes. [CAUSE] Commit |
||
Qu Wenruo
|
51415b6c1b |
btrfs: reloc: fix reloc root leak and NULL pointer dereference
[BUG]
When balance is canceled, there is a pretty high chance that unmounting
the fs can lead to lead the NULL pointer dereference:
BTRFS warning (device dm-3): page private not zero on page 223158272
...
BTRFS warning (device dm-3): page private not zero on page 223162368
BTRFS error (device dm-3): leaked root 18446744073709551608-304 refcount 1
BUG: kernel NULL pointer dereference, address: 0000000000000168
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 2 PID: 5793 Comm: umount Tainted: G O 5.7.0-rc5-custom+ #53
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:__lock_acquire+0x5dc/0x24c0
Call Trace:
lock_acquire+0xab/0x390
_raw_spin_lock+0x39/0x80
btrfs_release_extent_buffer_pages+0xd7/0x200 [btrfs]
release_extent_buffer+0xb2/0x170 [btrfs]
free_extent_buffer+0x66/0xb0 [btrfs]
btrfs_put_root+0x8e/0x130 [btrfs]
btrfs_check_leaked_roots.cold+0x5/0x5d [btrfs]
btrfs_free_fs_info+0xe5/0x120 [btrfs]
btrfs_kill_super+0x1f/0x30 [btrfs]
deactivate_locked_super+0x3b/0x80
deactivate_super+0x3e/0x50
cleanup_mnt+0x109/0x160
__cleanup_mnt+0x12/0x20
task_work_run+0x67/0xa0
exit_to_usermode_loop+0xc5/0xd0
syscall_return_slowpath+0x205/0x360
do_syscall_64+0x6e/0xb0
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x7fd028ef740b
[CAUSE]
When balance is canceled, all reloc roots are marked as orphan, and
orphan reloc roots are going to be cleaned up.
However for orphan reloc roots and merged reloc roots, their lifespan
are quite different:
Merged reloc roots | Orphan reloc roots by cancel
--------------------------------------------------------------------
create_reloc_root() | create_reloc_root()
|- refs == 1 | |- refs == 1
|
btrfs_grab_root(reloc_root); | btrfs_grab_root(reloc_root);
|- refs == 2 | |- refs == 2
|
root->reloc_root = reloc_root; | root->reloc_root = reloc_root;
>>> No difference so far <<<
|
prepare_to_merge() | prepare_to_merge()
|- btrfs_set_root_refs(item, 1);| |- if (!err) (err == -EINTR)
|
merge_reloc_roots() | merge_reloc_roots()
|- merge_reloc_root() | |- Doing nothing to put reloc root
|- insert_dirty_subvol() | |- refs == 2
|- __del_reloc_root() |
|- btrfs_put_root() |
|- refs == 1 |
>>> Now orphan reloc roots still have refs 2 <<<
|
clean_dirty_subvols() | clean_dirty_subvols()
|- btrfs_drop_snapshot() | |- btrfS_drop_snapshot()
|- reloc_root get freed | |- reloc_root still has refs 2
| related ebs get freed, but
| reloc_root still recorded in
| allocated_roots
btrfs_check_leaked_roots() | btrfs_check_leaked_roots()
|- No leaked roots | |- Leaked reloc_roots detected
| |- btrfs_put_root()
| |- free_extent_buffer(root->node);
| |- eb already freed, caused NULL
| pointer dereference
[FIX]
The fix is to clear fs_root->reloc_root and put it at
merge_reloc_roots() time, so that we won't leak reloc roots.
Fixes:
|
||
Robbie Ko
|
c11fbb6ed0 |
btrfs: reduce lock contention when creating snapshot
When creating a snapshot, ordered extents need to be flushed and this can take a long time. In create_snapshot there are two locks held when this happens: 1. Destination directory inode lock 2. Global subvolume semaphore This will unnecessarily block other operations like subvolume destroy, create, or setflag until the snapshot is created. We can fix that by moving the flush outside the locked section as this does not depend on the aforementioned locks. The code factors out the snapshot related work from create_snapshot to btrfs_mksnapshot. __btrfs_ioctl_snap_create btrfs_mksubvol create_subvol btrfs_mksnapshot <flush> btrfs_mksubvol create_snapshot Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Robbie Ko <robbieko@synology.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Qu Wenruo
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aeb935a455 |
btrfs: don't set SHAREABLE flag for data reloc tree
SHAREABLE flag is set for subvolumes because users can create snapshot for subvolumes, thus sharing tree blocks of them. But data reloc tree is not exposed to user space, as it's only an internal tree for data relocation, thus it doesn't need the full path replacement handling at all. This patch will make data reloc tree a non-shareable tree, and add btrfs_fs_info::data_reloc_root for data reloc tree, so relocation code can grab it from fs_info directly. This would slightly improve tree relocation, as now data reloc tree can go through regular COW routine to get relocated, without bothering the complex tree reloc tree routine. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Qu Wenruo
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82028e0a2a |
btrfs: inode: cleanup the log-tree exceptions in btrfs_truncate_inode_items()
There are a lot of root owner checks in btrfs_truncate_inode_items() like: if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state) || root == fs_info->tree_root) But considering that, only these trees can have INODE_ITEMs: - tree root (for v1 space cache) - subvolume trees - tree reloc trees - data reloc tree - log trees And since subvolume/tree reloc/data reloc trees all have SHAREABLE bit, and we're checking tree root manually, so above check is just excluding log trees. This patch will replace two of such checks to a simpler one: if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) This would merge btrfs_drop_extent_cache() and lock_extent_bits() call into the same if branch. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Qu Wenruo
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92a7cc4252 |
btrfs: rename BTRFS_ROOT_REF_COWS to BTRFS_ROOT_SHAREABLE
The name BTRFS_ROOT_REF_COWS is not very clear about the meaning. In fact, that bit can only be set to those trees: - Subvolume roots - Data reloc root - Reloc roots for above roots All other trees won't get this bit set. So just by the result, it is obvious that, roots with this bit set can have tree blocks shared with other trees. Either shared by snapshots, or by reloc roots (an special snapshot created by relocation). This patch will rename BTRFS_ROOT_REF_COWS to BTRFS_ROOT_SHAREABLE to make it easier to understand, and update all comment mentioning "reference counted" to follow the rename. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Anand Jain
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ae3e715f85 |
btrfs: drop stale reference to volume_mutex
Commit
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David Sterba
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583e4a2384 |
btrfs: update documentation of set/get helpers
Signed-off-by: David Sterba <dsterba@suse.com> |