- 02 Jul, 2019 13 commits
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Arnd Bergmann authored
gcc sometimes can't determine whether a variable has been initialized when both the initialization and the use are conditional: fs/btrfs/props.c: In function 'inherit_props': fs/btrfs/props.c:389:4: error: 'num_bytes' may be used uninitialized in this function [-Werror=maybe-uninitialized] btrfs_block_rsv_release(fs_info, trans->block_rsv, This code is fine. Unfortunately, I cannot think of a good way to rephrase it in a way that makes gcc understand this, so I add a bogus initialization the way one should not. Signed-off-by:Arnd Bergmann <arnd@arndb.de> Reviewed-by:
David Sterba <dsterba@suse.com> [ gcc 8 and 9 don't emit the warning ] Signed-off-by:
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Filipe Manana authored
Send always operates on read-only trees and always expected that while it is in progress, nothing changes in those trees. Due to that expectation and the fact that send is a read-only operation, it operates on commit roots and does not hold transaction handles. However relocation can COW nodes and leafs from read-only trees, which can cause unexpected failures and crashes (hitting BUG_ONs). while send using a node/leaf, it gets COWed, the transaction used to COW it is committed, a new transaction starts, the extent previously used for that node/leaf gets allocated, possibly for another tree, and the respective extent buffer' content changes while send is still using it. When this happens send normally fails with EIO being returned to user space and messages like the following are found in dmesg/syslog: [ 3408.699121] BTRFS error (device sdc): parent transid verify failed on 58703872 wanted 250 found 253 [ 3441.523123] BTRFS error (device sdc): did not find backref in send_root. inode=63211, offset=0, disk_byte=5222825984 found extent=5222825984 Other times, less often, we hit a BUG_ON() because an extent buffer that send is using used to be a node, and while send is still using it, it got COWed and got reused as a leaf while send is still using, producing the following trace: [ 3478.466280] ------------[ cut here ]------------ [ 3478.466282] kernel BUG at fs/btrfs/ctree.c:1806! [ 3478.466965] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI [ 3478.467635] CPU: 0 PID: 2165 Comm: btrfs Not tainted 5.0.0-btrfs-next-46 #1 [ 3478.468311] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [ 3478.469681] RIP: 0010:read_node_slot+0x122/0x130 [btrfs] (...) [ 3478.471758] RSP: 0018:ffffa437826bfaa0 EFLAGS: 00010246 [ 3478.472457] RAX: ffff961416ed7000 RBX: 000000000000003d RCX: 0000000000000002 [ 3478.473151] RDX: 000000000000003d RSI: ffff96141e387408 RDI: ffff961599b30000 [ 3478.473837] RBP: ffffa437826bfb8e R08: 0000000000000001 R09: ffffa437826bfb8e [ 3478.474515] R10: ffffa437826bfa70 R11: 0000000000000000 R12: ffff9614385c8708 [ 3478.475186] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 3478.475840] FS: 00007f8e0e9cc8c0(0000) GS:ffff9615b6a00000(0000) knlGS:0000000000000000 [ 3478.476489] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3478.477127] CR2: 00007f98b67a056e CR3: 0000000005df6005 CR4: 00000000003606f0 [ 3478.477762] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3478.478385] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3478.479003] Call Trace: [ 3478.479600] ? do_raw_spin_unlock+0x49/0xc0 [ 3478.480202] tree_advance+0x173/0x1d0 [btrfs] [ 3478.480810] btrfs_compare_trees+0x30c/0x690 [btrfs] [ 3478.481388] ? process_extent+0x1280/0x1280 [btrfs] [ 3478.481954] btrfs_ioctl_send+0x1037/0x1270 [btrfs] [ 3478.482510] _btrfs_ioctl_send+0x80/0x110 [btrfs] [ 3478.483062] btrfs_ioctl+0x13fe/0x3120 [btrfs] [ 3478.483581] ? rq_clock_task+0x2e/0x60 [ 3478.484086] ? wake_up_new_task+0x1f3/0x370 [ 3478.484582] ? do_vfs_ioctl+0xa2/0x6f0 [ 3478.485075] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [ 3478.485552] do_vfs_ioctl+0xa2/0x6f0 [ 3478.486016] ? __fget+0x113/0x200 [ 3478.486467] ksys_ioctl+0x70/0x80 [ 3478.486911] __x64_sys_ioctl+0x16/0x20 [ 3478.487337] do_syscall_64+0x60/0x1b0 [ 3478.487751] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 3478.488159] RIP: 0033:0x7f8e0d7d4dd7 (...) [ 3478.489349] RSP: 002b:00007ffcf6fb4908 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 3478.489742] RAX: ffffffffffffffda RBX: 0000000000000105 RCX: 00007f8e0d7d4dd7 [ 3478.490142] RDX: 00007ffcf6fb4990 RSI: 0000000040489426 RDI: 0000000000000005 [ 3478.490548] RBP: 0000000000000005 R08: 00007f8e0d6f3700 R09: 00007f8e0d6f3700 [ 3478.490953] R10: 00007f8e0d6f39d0 R11: 0000000000000202 R12: 0000000000000005 [ 3478.491343] R13: 00005624e0780020 R14: 0000000000000000 R15: 0000000000000001 (...) [ 3478.493352] ---[ end trace d5f537302be4f8c8 ]--- Another possibility, much less likely to happen, is that send will not fail but the contents of the stream it produces may not be correct. To avoid this, do not allow send and relocation (balance) to run in parallel. In the long term the goal is to allow for both to be able to run concurrently without any problems, but that will take a significant effort in development and testing. Signed-off-by:
Filipe Manana <fdmanana@suse.com> Reviewed-by:
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David Sterba authored
The real meaning of that constant is not clear from the context due to the target device inclusion. Signed-off-by: -
David Sterba authored
We don't need to enumerate the profiles, use the mask for consistency. Signed-off-by: -
David Sterba authored
Preparatory patch for additional RAID1 profiles with more copies. The mask will contain 3-copy and 4-copy, most of the checks for plain RAID1 work the same for the other profiles. Signed-off-by: -
Qu Wenruo authored
[BUG] Lockdep will report the following circular locking dependency: WARNING: possible circular locking dependency detected 5.2.0-rc2-custom #24 Tainted: G O ------------------------------------------------------ btrfs/8631 is trying to acquire lock: 000000002536438c (&fs_info->qgroup_ioctl_lock#2){+.+.}, at: btrfs_qgroup_inherit+0x40/0x620 [btrfs] but task is already holding lock: 000000003d52cc23 (&fs_info->tree_log_mutex){+.+.}, at: create_pending_snapshot+0x8b6/0xe60 [btrfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&fs_info->tree_log_mutex){+.+.}: __mutex_lock+0x76/0x940 mutex_lock_nested+0x1b/0x20 btrfs_commit_transaction+0x475/0xa00 [btrfs] btrfs_commit_super+0x71/0x80 [btrfs] close_ctree+0x2bd/0x320 [btrfs] btrfs_put_super+0x15/0x20 [btrfs] generic_shutdown_super+0x72/0x110 kill_anon_super+0x18/0x30 btrfs_kill_super+0x16/0xa0 [btrfs] deactivate_locked_super+0x3a/0x80 deactivate_super+0x51/0x60 cleanup_mnt+0x3f/0x80 __cleanup_mnt+0x12/0x20 task_work_run+0x94/0xb0 exit_to_usermode_loop+0xd8/0xe0 do_syscall_64+0x210/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (&fs_info->reloc_mutex){+.+.}: __mutex_lock+0x76/0x940 mutex_lock_nested+0x1b/0x20 btrfs_commit_transaction+0x40d/0xa00 [btrfs] btrfs_quota_enable+0x2da/0x730 [btrfs] btrfs_ioctl+0x2691/0x2b40 [btrfs] do_vfs_ioctl+0xa9/0x6d0 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x65/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&fs_info->qgroup_ioctl_lock#2){+.+.}: lock_acquire+0xa7/0x190 __mutex_lock+0x76/0x940 mutex_lock_nested+0x1b/0x20 btrfs_qgroup_inherit+0x40/0x620 [btrfs] create_pending_snapshot+0x9d7/0xe60 [btrfs] create_pending_snapshots+0x94/0xb0 [btrfs] btrfs_commit_transaction+0x415/0xa00 [btrfs] btrfs_mksubvol+0x496/0x4e0 [btrfs] btrfs_ioctl_snap_create_transid+0x174/0x180 [btrfs] btrfs_ioctl_snap_create_v2+0x11c/0x180 [btrfs] btrfs_ioctl+0xa90/0x2b40 [btrfs] do_vfs_ioctl+0xa9/0x6d0 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x65/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: &fs_info->qgroup_ioctl_lock#2 --> &fs_info->reloc_mutex --> &fs_info->tree_log_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->tree_log_mutex); lock(&fs_info->reloc_mutex); lock(&fs_info->tree_log_mutex); lock(&fs_info->qgroup_ioctl_lock#2); *** DEADLOCK *** 6 locks held by btrfs/8631: #0: 00000000ed8f23f6 (sb_writers#12){.+.+}, at: mnt_want_write_file+0x28/0x60 #1: 000000009fb1597a (&type->i_mutex_dir_key#10/1){+.+.}, at: btrfs_mksubvol+0x70/0x4e0 [btrfs] #2: 0000000088c5ad88 (&fs_info->subvol_sem){++++}, at: btrfs_mksubvol+0x128/0x4e0 [btrfs] #3: 000000009606fc3e (sb_internal#2){.+.+}, at: start_transaction+0x37a/0x520 [btrfs] #4: 00000000f82bbdf5 (&fs_info->reloc_mutex){+.+.}, at: btrfs_commit_transaction+0x40d/0xa00 [btrfs] #5: 000000003d52cc23 (&fs_info->tree_log_mutex){+.+.}, at: create_pending_snapshot+0x8b6/0xe60 [btrfs] [CAUSE] Due to the delayed subvolume creation, we need to call btrfs_qgroup_inherit() inside commit transaction code, with a lot of other mutex hold. This hell of lock chain can lead to above problem. [FIX] On the other hand, we don't really need to hold qgroup_ioctl_lock if we're in the context of create_pending_snapshot(). As in that context, we're the only one being able to modify qgroup. All other qgroup functions which needs qgroup_ioctl_lock are either holding a transaction handle, or will start a new transaction: Functions will start a new transaction(): * btrfs_quota_enable() * btrfs_quota_disable() Functions hold a transaction handler: * btrfs_add_qgroup_relation() * btrfs_del_qgroup_relation() * btrfs_create_qgroup() * btrfs_remove_qgroup() * btrfs_limit_qgroup() * btrfs_qgroup_inherit() call inside create_subvol() So we have a higher level protection provided by transaction, thus we don't need to always hold qgroup_ioctl_lock in btrfs_qgroup_inherit(). Only the btrfs_qgroup_inherit() call in create_subvol() needs to hold qgroup_ioctl_lock, while the btrfs_qgroup_inherit() call in create_pending_snapshot() is already protected by transaction. So the fix is to detect the context by checking trans->transaction->state. If we're at TRANS_STATE_COMMIT_DOING, then we're in commit transaction context and no need to get the mutex. Reported-by:Nikolay Borisov <nborisov@suse.com> Signed-off-by:
Qu Wenruo <wqu@suse.com> Signed-off-by:
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Johannes Thumshirn authored
Nikolay reported the following KASAN splat when running btrfs/048: [ 1843.470920] ================================================================== [ 1843.471971] BUG: KASAN: slab-out-of-bounds in strncmp+0x66/0xb0 [ 1843.472775] Read of size 1 at addr ffff888111e369e2 by task btrfs/3979 [ 1843.473904] CPU: 3 PID: 3979 Comm: btrfs Not tainted 5.2.0-rc3-default #536 [ 1843.475009] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 1843.476322] Call Trace: [ 1843.476674] dump_stack+0x7c/0xbb [ 1843.477132] ? strncmp+0x66/0xb0 [ 1843.477587] print_address_description+0x114/0x320 [ 1843.478256] ? strncmp+0x66/0xb0 [ 1843.478740] ? strncmp+0x66/0xb0 [ 1843.479185] __kasan_report+0x14e/0x192 [ 1843.479759] ? strncmp+0x66/0xb0 [ 1843.480209] kasan_report+0xe/0x20 [ 1843.480679] strncmp+0x66/0xb0 [ 1843.481105] prop_compression_validate+0x24/0x70 [ 1843.481798] btrfs_xattr_handler_set_prop+0x65/0x160 [ 1843.482509] __vfs_setxattr+0x71/0x90 [ 1843.483012] __vfs_setxattr_noperm+0x84/0x130 [ 1843.483606] vfs_setxattr+0xac/0xb0 [ 1843.484085] setxattr+0x18c/0x230 [ 1843.484546] ? vfs_setxattr+0xb0/0xb0 [ 1843.485048] ? __mod_node_page_state+0x1f/0xa0 [ 1843.485672] ? _raw_spin_unlock+0x24/0x40 [ 1843.486233] ? __handle_mm_fault+0x988/0x1290 [ 1843.486823] ? lock_acquire+0xb4/0x1e0 [ 1843.487330] ? lock_acquire+0xb4/0x1e0 [ 1843.487842] ? mnt_want_write_file+0x3c/0x80 [ 1843.488442] ? debug_lockdep_rcu_enabled+0x22/0x40 [ 1843.489089] ? rcu_sync_lockdep_assert+0xe/0x70 [ 1843.489707] ? __sb_start_write+0x158/0x200 [ 1843.490278] ? mnt_want_write_file+0x3c/0x80 [ 1843.490855] ? __mnt_want_write+0x98/0xe0 [ 1843.491397] __x64_sys_fsetxattr+0xba/0xe0 [ 1843.492201] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 1843.493201] do_syscall_64+0x6c/0x230 [ 1843.493988] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1843.495041] RIP: 0033:0x7fa7a8a7707a [ 1843.495819] Code: 48 8b 0d 21 de 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 be 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ee dd 2b 00 f7 d8 64 89 01 48 [ 1843.499203] RSP: 002b:00007ffcb73bca38 EFLAGS: 00000202 ORIG_RAX: 00000000000000be [ 1843.500210] RAX: ffffffffffffffda RBX: 00007ffcb73bda9d RCX: 00007fa7a8a7707a [ 1843.501170] RDX: 00007ffcb73bda9d RSI: 00000000006dc050 RDI: 0000000000000003 [ 1843.502152] RBP: 00000000006dc050 R08: 0000000000000000 R09: 0000000000000000 [ 1843.503109] R10: 0000000000000002 R11: 0000000000000202 R12: 00007ffcb73bda91 [ 1843.504055] R13: 0000000000000003 R14: 00007ffcb73bda82 R15: ffffffffffffffff [ 1843.505268] Allocated by task 3979: [ 1843.505771] save_stack+0x19/0x80 [ 1843.506211] __kasan_kmalloc.constprop.5+0xa0/0xd0 [ 1843.506836] setxattr+0xeb/0x230 [ 1843.507264] __x64_sys_fsetxattr+0xba/0xe0 [ 1843.507886] do_syscall_64+0x6c/0x230 [ 1843.508429] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1843.509558] Freed by task 0: [ 1843.510188] (stack is not available) [ 1843.511309] The buggy address belongs to the object at ffff888111e369e0 which belongs to the cache kmalloc-8 of size 8 [ 1843.514095] The buggy address is located 2 bytes inside of 8-byte region [ffff888111e369e0, ffff888111e369e8) [ 1843.516524] The buggy address belongs to the page: [ 1843.517561] page:ffff88813f478d80 refcount:1 mapcount:0 mapping:ffff88811940c300 index:0xffff888111e373b8 compound_mapcount: 0 [ 1843.519993] flags: 0x4404000010200(slab|head) [ 1843.520951] raw: 0004404000010200 ffff88813f48b008 ffff888119403d50 ffff88811940c300 [ 1843.522616] raw: ffff888111e373b8 000000000016000f 00000001ffffffff 0000000000000000 [ 1843.524281] page dumped because: kasan: bad access detected [ 1843.525936] Memory state around the buggy address: [ 1843.526975] ffff888111e36880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.528479] ffff888111e36900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.530138] >ffff888111e36980: fc fc fc fc fc fc fc fc fc fc fc fc 02 fc fc fc [ 1843.531877] ^ [ 1843.533287] ffff888111e36a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.534874] ffff888111e36a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.536468] ================================================================== This is caused by supplying a too short compression value ('lz') in the test-case and comparing it to 'lzo' with strncmp() and a length of 3. strncmp() read past the 'lz' when looking for the 'o' and thus caused an out-of-bounds read. Introduce a new check 'btrfs_compress_is_valid_type()' which not only checks the user-supplied value against known compression types, but also employs checks for too short values. Reported-by:Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by:
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Filipe Manana authored
When we log an inode, regardless of logging it completely or only that it exists, we always update it as logged (logged_trans and last_log_commit fields of the inode are updated). This is generally fine and avoids future attempts to log it from having to do repeated work that brings no value. However, if we write data to a file, then evict its inode after all the dealloc was flushed (and ordered extents completed), rename the file and fsync it, we end up not logging the new extents, since the rename may result in logging that the inode exists in case the parent directory was logged before. The following reproducer shows and explains how this can happen: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir /mnt/dir $ touch /mnt/dir/foo $ touch /mnt/dir/bar # Do a direct IO write instead of a buffered write because with a # buffered write we would need to make sure dealloc gets flushed and # complete before we do the inode eviction later, and we can not do that # from user space with call to things such as sync(2) since that results # in a transaction commit as well. $ xfs_io -d -c "pwrite -S 0xd3 0 4K" /mnt/dir/bar # Keep the directory dir in use while we evict inodes. We want our file # bar's inode to be evicted but we don't want our directory's inode to # be evicted (if it were evicted too, we would not be able to reproduce # the issue since the first fsync below, of file foo, would result in a # transaction commit. $ ( cd /mnt/dir; while true; do :; done ) & $ pid=$! # Wait a bit to give time for the background process to chdir. $ sleep 0.1 # Evict all inodes, except the inode for the directory dir because it is # currently in use by our background process. $ echo 2 > /proc/sys/vm/drop_caches # fsync file foo, which ends up persisting information about the parent # directory because it is a new inode. $ xfs_io -c fsync /mnt/dir/foo # Rename bar, this results in logging that this inode exists (inode item, # names, xattrs) because the parent directory is in the log. $ mv /mnt/dir/bar /mnt/dir/baz # Now fsync baz, which ends up doing absolutely nothing because of the # rename operation which logged that the inode exists only. $ xfs_io -c fsync /mnt/dir/baz <power failure> $ mount /dev/sdb /mnt $ od -t x1 -A d /mnt/dir/baz 0000000 --> Empty file, data we wrote is missing. Fix this by not updating last_sub_trans of an inode when we are logging only that it exists and the inode was not yet logged since it was loaded from disk (full_sync bit set), this is enough to make btrfs_inode_in_log() return false for this scenario and make us log the inode. The logged_trans of the inode is still always setsince that alone is used to track if names need to be deleted as part of unlink operations. Fixes: 257c62e1 ("Btrfs: avoid tree log commit when there are no changes") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: -
David Sterba authored
The incompat bit for RAID56 is set either at mount time or automatically when the profile is used by balance. The part where the bit is removed is missing and can be unexpected or undesired when an older kernel is needed. This patch will drop the incompat bit after this command, assuming that RAID5 profile is not used by system or metadata: $ btrfs balance start -dconvert=raid5 /mnt $ btrfs balance start -dconvert=raid1 /mnt This will print "clearing 128 feature flag" to the system log. The patch is safe for backporting to older kernels. Reported-by:
Hugo Mills <hugo@carfax.org.uk> Signed-off-by:
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David Sterba authored
The write_locks is either 0 or 1 and always updated under the lock, so we don't need the atomic_t semantics. Reviewed-by:
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David Sterba authored
The spinning_writers is either 0 or 1 and always updated under the lock, so we don't need the atomic_t semantics. Signed-off-by: -
David Sterba authored
The blocking_writers is either 0 or 1 and always updated under the lock, so we don't need the atomic_t semantics. Reviewed-by:
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David Sterba authored
Turn the comment about required lock into an assertion. Reviewed-by:
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- 01 Jul, 2019 27 commits
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David Sterba authored
There are no concerns about locking during the selftests so the locks are not necessary, but following patches will add lockdep assertions to add_extent_mapping so this is needed in tests too. Reviewed-by:
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Nikolay Borisov authored
The function has a lot of return values and specific conventions making it cumbersome to understand what's returned. Have a go at documenting its parameters and return values. Reviewed-by:
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Nikolay Borisov authored
Currently find_first_clear_extent_bit always returns a range whose starting value is >= passed 'start'. This implicit trimming behavior is somewhat subtle and an implementation detail. Instead, this patch modifies the function such that now it always returns the range which contains passed 'start' and has the given bits unset. This range could either be due to presence of existing records which contains 'start' but have the bits unset or because there are no records that contain the given starting offset. This patch also adds test cases which cover find_first_clear_extent_bit since they were missing up until now. Reviewed-by:
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Nikolay Borisov authored
Currently the first megabyte on a device housing a btrfs filesystem is exempt from allocation and trimming. Currently this is not a problem since 'start' is set to 1M at the beginning of btrfs_trim_free_extents and find_first_clear_extent_bit always returns a range that is >= start. However, in a follow up patch find_first_clear_extent_bit will be changed such that it will return a range containing 'start' and this range may very well be 0...>=1M so 'start'. Future proof the sole user of find_first_clear_extent_bit by setting 'start' after the function is called. No functional changes. Reviewed-by:
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David Sterba authored
The filename:line format is commonly understood by editors and can be copy&pasted more easily than the current format. Signed-off-by: -
Johannes Thumshirn authored
btrfs_print_data_csum_error() still assumed checksums to be 32 bit in size. Make it size agnostic. Reviewed-by:
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Johannes Thumshirn authored
Currently btrfs_csum_data() relied on the crc32c() wrapper around the crypto framework for calculating the CRCs. As we have our own crypto_shash structure in the fs_info now, we can directly call into the crypto framework without going trough the wrapper. This way we can even remove the btrfs_csum_data() and btrfs_csum_final() wrappers. The module dependency on crc32c is preserved via MODULE_SOFTDEP("pre: crc32c"), which was previously provided by LIBCRC32C config option doing the same. Signed-off-by: -
Johannes Thumshirn authored
Add boilerplate code for directly including the crypto framework. This helps us flipping the switch for new algorithms. Reviewed-by:
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Johannes Thumshirn authored
Now that we have already checked for a valid checksum type before calling btrfs_check_super_csum(), it can be simplified even further. While at it get rid of the implicit size assumption of the resulting checksum as well. This is a preparation for changing all checksum functionality to use the crypto layer later. Reviewed-by:
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Johannes Thumshirn authored
Now that we have factorerd out the superblock checksum type validation, we can check for supported superblock checksum types before doing the actual validation of the superblock read from disk. This leads the path to further simplifications of btrfs_check_super_csum() later on. Reviewed-by:
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Johannes Thumshirn authored
Currently btrfs is only supporting CRC32C as checksumming algorithm. As this is about to change provide a function to validate the checksum type in the superblock against all possible algorithms. This makes adding new algorithms easier as there are fewer places to adjust when adding new algorithms. Reviewed-by:
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Johannes Thumshirn authored
Add a small helper for btrfs_print_data_csum_error() which formats the checksum according to it's type for pretty printing. Signed-off-by:
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Johannes Thumshirn authored
BTRFS has the implicit assumption that a checksum in compressed_bio is 4 bytes. While this is true for CRC32C, it is not for any other checksum. Change the data type to be a byte array and adjust loop index calculation accordingly. Signed-off-by:
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Johannes Thumshirn authored
BTRFS has the implicit assumption that a checksum in btrfs_orderd_sums is 4 bytes. While this is true for CRC32C, it is not for any other checksum. Change the data type to be a byte array and adjust loop index calculation accordingly. This includes moving the adjustment of 'index' by 'ins_size' in btrfs_csum_file_blocks() before dividing 'ins_size' by the checksum size, because before this patch the 'sums' member of 'struct btrfs_ordered_sum' was 4 Bytes in size and afterwards it is only one byte. Reviewed-by:
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Johannes Thumshirn authored
The CRC checksum in the free space cache is not dependant on the super block's csum_type field but always a CRC32C. So use btrfs_crc32c() and btrfs_crc32c_final() instead of btrfs_csum_data() and btrfs_csum_final() for computing these checksums. Reviewed-by:
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Johannes Thumshirn authored
Commit 9678c543 ("btrfs: Remove custom crc32c init code") removed the btrfs_crc32c() function, because it was a duplicate of the crc32c() library function we already have in the kernel. Resurrect it as a shim wrapper over crc32c() to make following transformations of the checksumming code in btrfs easier. Also provide a btrfs_crc32_final() to ease following transformations. Reviewed-by:
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Johannes Thumshirn authored
btrfsic_test_for_metadata() directly calls the crc32c() library function for calculating the CRC32C checksum, but then uses btrfs_csum_final() to invert the result. To ease further refactoring and development around checksumming in BTRFS convert to calling btrfs_csum_data(), which is a wrapper around crc32c(). Reviewed-by:
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Qu Wenruo authored
btrfs: Flush before reflinking any extent to prevent NOCOW write falling back to COW without data reservation [BUG] The following script can cause unexpected fsync failure: #!/bin/bash dev=/dev/test/test mnt=/mnt/btrfs mkfs.btrfs -f $dev -b 512M > /dev/null mount $dev $mnt -o nospace_cache # Prealloc one extent xfs_io -f -c "falloc 8k 64m" $mnt/file1 # Fill the remaining data space xfs_io -f -c "pwrite 0 -b 4k 512M" $mnt/padding sync # Write into the prealloc extent xfs_io -c "pwrite 1m 16m" $mnt/file1 # Reflink then fsync, fsync would fail due to ENOSPC xfs_io -c "reflink $mnt/file1 8k 0 4k" -c "fsync" $mnt/file1 umount $dev The fsync fails with ENOSPC, and the last page of the buffered write is lost. [CAUSE] This is caused by: - Btrfs' back reference only has extent level granularity So write into shared extent must be COWed even only part of the extent is shared. So for above script we have: - fallocate Create a preallocated extent where we can do NOCOW write. - fill all the remaining data and unallocated space - buffered write into preallocated space As we have not enough space available for data and the extent is not shared (yet) we fall into NOCOW mode. - reflink Now part of the large preallocated extent is shared, later write into that extent must be COWed. - fsync triggers writeback But now the extent is shared and therefore we must fallback into COW mode, which fails with ENOSPC since there's not enough space to allocate data extents. [WORKAROUND] The workaround is to ensure any buffered write in the related extents (not just the reflink source range) get flushed before reflink/dedupe, so that NOCOW writes succeed that happened before reflinking succeed. The workaround is expensive, we could do it better by only flushing NOCOW range, but that needs extra accounting for NOCOW range. For now, fix the possible data loss first. Reviewed-by:
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Nikolay Borisov authored
The first thing code does in check_can_nocow is trying to block concurrent snapshots. If this fails (due to snpashot already being in progress) the function returns ENOSPC which makes no sense. Instead return EAGAIN. Despite this return value not being propagated to callers it's good practice to return the closest in terms of semantics error code. No functional changes. Signed-off-by:
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Nikolay Borisov authored
Signed-off-by:
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Nikolay Borisov authored
In case no cached_state argument is passed to btrfs_lock_and_flush_ordered_range use one locally in the function. This optimises the case when an ordered extent is found since the unlock function will be able to unlock that state directly without searching for it again. Reviewed-by:
Josef Bacik <josef@toxicpanda.com> Signed-off-by:
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Nikolay Borisov authored
There several functions which open code btrfs_lock_and_flush_ordered_range, just replace them with a call to the function. No functional changes. Reviewed-by:
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Nikolay Borisov authored
There is a certain idiom used in multiple places in btrfs' codebase, dealing with flushing an ordered range. Factor this in a separate function that can be reused. Future patches will replace the existing code with that function. Reviewed-by:
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Qu Wenruo authored
At the context of btrfs_run_delalloc_range(), we haven't started/joined a transaction, thus even something went wrong, we can't and won't abort transaction, thus no way to make the fs RO. Reviewed-by:
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Qu Wenruo authored
Add trace event for update_bytes_pinned() and update_bytes_may_use() to detect underflow better. The output would be something like (only showing data part): ## Buffered write start, 16K total ## 2255.954 xfs_io/860 btrfs:update_bytes_may_use:(nil)U: type=DATA old=0 diff=4096 2257.169 sudo/860 btrfs:update_bytes_may_use:(nil)U: type=DATA old=4096 diff=4096 2257.346 sudo/860 btrfs:update_bytes_may_use:(nil)U: type=DATA old=8192 diff=4096 2257.542 sudo/860 btrfs:update_bytes_may_use:(nil)U: type=DATA old=12288 diff=4096 ## Delalloc start ## 3727.853 kworker/u8:3-e/700 btrfs:update_bytes_may_use:(nil)U: type=DATA old=16384 diff=-16384 ## Space cache update ## 3733.132 sudo/862 btrfs:update_bytes_may_use:(nil)U: type=DATA old=0 diff=65536 3733.169 sudo/862 btrfs:update_bytes_may_use:(nil)U: type=DATA old=65536 diff=-65536 3739.868 sudo/862 btrfs:update_bytes_may_use:(nil)U: type=DATA old=0 diff=65536 3739.891 sudo/862 btrfs:update_bytes_may_use:(nil)U: type=DATA old=65536 diff=-65536 These two trace events will allow bcc tool to probe btrfs_space_info changes and detect underflow with more details (e.g. backtrace for each update). Signed-off-by:
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Qu Wenruo authored
Just add a safe net for btrfs_space_info member updating. Signed-off-by:
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David Sterba authored
There are several places that call nr_data_stripes, but this value does not change. Signed-off-by:
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