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2022-03-23btrfs: skip reserved bytes warning on unmount after log cleanup failureFilipe Manana1-0/+7
commit 40cdc509877bacb438213b83c7541c5e24a1d9ec upstream. After the recent changes made by commit c2e39305299f01 ("btrfs: clear extent buffer uptodate when we fail to write it") and its followup fix, commit 651740a5024117 ("btrfs: check WRITE_ERR when trying to read an extent buffer"), we can now end up not cleaning up space reservations of log tree extent buffers after a transaction abort happens, as well as not cleaning up still dirty extent buffers. This happens because if writeback for a log tree extent buffer failed, then we have cleared the bit EXTENT_BUFFER_UPTODATE from the extent buffer and we have also set the bit EXTENT_BUFFER_WRITE_ERR on it. Later on, when trying to free the log tree with free_log_tree(), which iterates over the tree, we can end up getting an -EIO error when trying to read a node or a leaf, since read_extent_buffer_pages() returns -EIO if an extent buffer does not have EXTENT_BUFFER_UPTODATE set and has the EXTENT_BUFFER_WRITE_ERR bit set. Getting that -EIO means that we return immediately as we can not iterate over the entire tree. In that case we never update the reserved space for an extent buffer in the respective block group and space_info object. When this happens we get the following traces when unmounting the fs: [174957.284509] BTRFS: error (device dm-0) in cleanup_transaction:1913: errno=-5 IO failure [174957.286497] BTRFS: error (device dm-0) in free_log_tree:3420: errno=-5 IO failure [174957.399379] ------------[ cut here ]------------ [174957.402497] WARNING: CPU: 2 PID: 3206883 at fs/btrfs/block-group.c:127 btrfs_put_block_group+0x77/0xb0 [btrfs] [174957.407523] Modules linked in: btrfs overlay dm_zero (...) [174957.424917] CPU: 2 PID: 3206883 Comm: umount Tainted: G W 5.16.0-rc5-btrfs-next-109 #1 [174957.426689] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [174957.428716] RIP: 0010:btrfs_put_block_group+0x77/0xb0 [btrfs] [174957.429717] Code: 21 48 8b bd (...) [174957.432867] RSP: 0018:ffffb70d41cffdd0 EFLAGS: 00010206 [174957.433632] RAX: 0000000000000001 RBX: ffff8b09c3848000 RCX: ffff8b0758edd1c8 [174957.434689] RDX: 0000000000000001 RSI: ffffffffc0b467e7 RDI: ffff8b0758edd000 [174957.436068] RBP: ffff8b0758edd000 R08: 0000000000000000 R09: 0000000000000000 [174957.437114] R10: 0000000000000246 R11: 0000000000000000 R12: ffff8b09c3848148 [174957.438140] R13: ffff8b09c3848198 R14: ffff8b0758edd188 R15: dead000000000100 [174957.439317] FS: 00007f328fb82800(0000) GS:ffff8b0a2d200000(0000) knlGS:0000000000000000 [174957.440402] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [174957.441164] CR2: 00007fff13563e98 CR3: 0000000404f4e005 CR4: 0000000000370ee0 [174957.442117] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [174957.443076] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [174957.443948] Call Trace: [174957.444264] <TASK> [174957.444538] btrfs_free_block_groups+0x255/0x3c0 [btrfs] [174957.445238] close_ctree+0x301/0x357 [btrfs] [174957.445803] ? call_rcu+0x16c/0x290 [174957.446250] generic_shutdown_super+0x74/0x120 [174957.446832] kill_anon_super+0x14/0x30 [174957.447305] btrfs_kill_super+0x12/0x20 [btrfs] [174957.447890] deactivate_locked_super+0x31/0xa0 [174957.448440] cleanup_mnt+0x147/0x1c0 [174957.448888] task_work_run+0x5c/0xa0 [174957.449336] exit_to_user_mode_prepare+0x1e5/0x1f0 [174957.449934] syscall_exit_to_user_mode+0x16/0x40 [174957.450512] do_syscall_64+0x48/0xc0 [174957.450980] entry_SYSCALL_64_after_hwframe+0x44/0xae [174957.451605] RIP: 0033:0x7f328fdc4a97 [174957.452059] Code: 03 0c 00 f7 (...) [174957.454320] RSP: 002b:00007fff13564ec8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [174957.455262] RAX: 0000000000000000 RBX: 00007f328feea264 RCX: 00007f328fdc4a97 [174957.456131] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000560b8ae51dd0 [174957.457118] RBP: 0000560b8ae51ba0 R08: 0000000000000000 R09: 00007fff13563c40 [174957.458005] R10: 00007f328fe49fc0 R11: 0000000000000246 R12: 0000000000000000 [174957.459113] R13: 0000560b8ae51dd0 R14: 0000560b8ae51cb0 R15: 0000000000000000 [174957.460193] </TASK> [174957.460534] irq event stamp: 0 [174957.461003] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [174957.461947] hardirqs last disabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040 [174957.463147] softirqs last enabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040 [174957.465116] softirqs last disabled at (0): [<0000000000000000>] 0x0 [174957.466323] ---[ end trace bc7ee0c490bce3af ]--- [174957.467282] ------------[ cut here ]------------ [174957.468184] WARNING: CPU: 2 PID: 3206883 at fs/btrfs/block-group.c:3976 btrfs_free_block_groups+0x330/0x3c0 [btrfs] [174957.470066] Modules linked in: btrfs overlay dm_zero (...) [174957.483137] CPU: 2 PID: 3206883 Comm: umount Tainted: G W 5.16.0-rc5-btrfs-next-109 #1 [174957.484691] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [174957.486853] RIP: 0010:btrfs_free_block_groups+0x330/0x3c0 [btrfs] [174957.488050] Code: 00 00 00 ad de (...) [174957.491479] RSP: 0018:ffffb70d41cffde0 EFLAGS: 00010206 [174957.492520] RAX: ffff8b08d79310b0 RBX: ffff8b09c3848000 RCX: 0000000000000000 [174957.493868] RDX: 0000000000000001 RSI: fffff443055ee600 RDI: ffffffffb1131846 [174957.495183] RBP: ffff8b08d79310b0 R08: 0000000000000000 R09: 0000000000000000 [174957.496580] R10: 0000000000000001 R11: 0000000000000000 R12: ffff8b08d7931000 [174957.498027] R13: ffff8b09c38492b0 R14: dead000000000122 R15: dead000000000100 [174957.499438] FS: 00007f328fb82800(0000) GS:ffff8b0a2d200000(0000) knlGS:0000000000000000 [174957.500990] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [174957.502117] CR2: 00007fff13563e98 CR3: 0000000404f4e005 CR4: 0000000000370ee0 [174957.503513] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [174957.504864] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [174957.506167] Call Trace: [174957.506654] <TASK> [174957.507047] close_ctree+0x301/0x357 [btrfs] [174957.507867] ? call_rcu+0x16c/0x290 [174957.508567] generic_shutdown_super+0x74/0x120 [174957.509447] kill_anon_super+0x14/0x30 [174957.510194] btrfs_kill_super+0x12/0x20 [btrfs] [174957.511123] deactivate_locked_super+0x31/0xa0 [174957.511976] cleanup_mnt+0x147/0x1c0 [174957.512610] task_work_run+0x5c/0xa0 [174957.513309] exit_to_user_mode_prepare+0x1e5/0x1f0 [174957.514231] syscall_exit_to_user_mode+0x16/0x40 [174957.515069] do_syscall_64+0x48/0xc0 [174957.515718] entry_SYSCALL_64_after_hwframe+0x44/0xae [174957.516688] RIP: 0033:0x7f328fdc4a97 [174957.517413] Code: 03 0c 00 f7 d8 (...) [174957.521052] RSP: 002b:00007fff13564ec8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [174957.522514] RAX: 0000000000000000 RBX: 00007f328feea264 RCX: 00007f328fdc4a97 [174957.523950] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000560b8ae51dd0 [174957.525375] RBP: 0000560b8ae51ba0 R08: 0000000000000000 R09: 00007fff13563c40 [174957.526763] R10: 00007f328fe49fc0 R11: 0000000000000246 R12: 0000000000000000 [174957.528058] R13: 0000560b8ae51dd0 R14: 0000560b8ae51cb0 R15: 0000000000000000 [174957.529404] </TASK> [174957.529843] irq event stamp: 0 [174957.530256] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [174957.531061] hardirqs last disabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040 [174957.532075] softirqs last enabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040 [174957.533083] softirqs last disabled at (0): [<0000000000000000>] 0x0 [174957.533865] ---[ end trace bc7ee0c490bce3b0 ]--- [174957.534452] BTRFS info (device dm-0): space_info 4 has 1070841856 free, is not full [174957.535404] BTRFS info (device dm-0): space_info total=1073741824, used=2785280, pinned=0, reserved=49152, may_use=0, readonly=65536 zone_unusable=0 [174957.537029] BTRFS info (device dm-0): global_block_rsv: size 0 reserved 0 [174957.537859] BTRFS info (device dm-0): trans_block_rsv: size 0 reserved 0 [174957.538697] BTRFS info (device dm-0): chunk_block_rsv: size 0 reserved 0 [174957.539552] BTRFS info (device dm-0): delayed_block_rsv: size 0 reserved 0 [174957.540403] BTRFS info (device dm-0): delayed_refs_rsv: size 0 reserved 0 This also means that in case we have log tree extent buffers that are still dirty, we can end up not cleaning them up in case we find an extent buffer with EXTENT_BUFFER_WRITE_ERR set on it, as in that case we have no way for iterating over the rest of the tree. This issue is very often triggered with test cases generic/475 and generic/648 from fstests. The issue could almost be fixed by iterating over the io tree attached to each log root which keeps tracks of the range of allocated extent buffers, log_root->dirty_log_pages, however that does not work and has some inconveniences: 1) After we sync the log, we clear the range of the extent buffers from the io tree, so we can't find them after writeback. We could keep the ranges in the io tree, with a separate bit to signal they represent extent buffers already written, but that means we need to hold into more memory until the transaction commits. How much more memory is used depends a lot on whether we are able to allocate contiguous extent buffers on disk (and how often) for a log tree - if we are able to, then a single extent state record can represent multiple extent buffers, otherwise we need multiple extent state record structures to track each extent buffer. In fact, my earlier approach did that: https://lore.kernel.org/linux-btrfs/3aae7c6728257c7ce2279d6660ee2797e5e34bbd.1641300250.git.fdmanana@suse.com/ However that can cause a very significant negative impact on performance, not only due to the extra memory usage but also because we get a larger and deeper dirty_log_pages io tree. We got a report that, on beefy machines at least, we can get such performance drop with fsmark for example: https://lore.kernel.org/linux-btrfs/20220117082426.GE32491@xsang-OptiPlex-9020/ 2) We would be doing it only to deal with an unexpected and exceptional case, which is basically failure to read an extent buffer from disk due to IO failures. On a healthy system we don't expect transaction aborts to happen after all; 3) Instead of relying on iterating the log tree or tracking the ranges of extent buffers in the dirty_log_pages io tree, using the radix tree that tracks extent buffers (fs_info->buffer_radix) to find all log tree extent buffers is not reliable either, because after writeback of an extent buffer it can be evicted from memory by the release page callback of the btree inode (btree_releasepage()). Since there's no way to be able to properly cleanup a log tree without being able to read its extent buffers from disk and without using more memory to track the logical ranges of the allocated extent buffers do the following: 1) When we fail to cleanup a log tree, setup a flag that indicates that failure; 2) Trigger writeback of all log tree extent buffers that are still dirty, and wait for the writeback to complete. This is just to cleanup their state, page states, page leaks, etc; 3) When unmounting the fs, ignore if the number of bytes reserved in a block group and in a space_info is not 0 if, and only if, we failed to cleanup a log tree. Also ignore only for metadata block groups and the metadata space_info object. This is far from a perfect solution, but it serves to silence test failures such as those from generic/475 and generic/648. However having a non-zero value for the reserved bytes counters on unmount after a transaction abort, is not such a terrible thing and it's completely harmless, it does not affect the filesystem integrity in any way. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-16btrfs: make send work with concurrent block group relocationFilipe Manana1-8/+6
commit d96b34248c2f4ea8cd09286090f2f6f77102eaab upstream. We don't allow send and balance/relocation to run in parallel in order to prevent send failing or silently producing some bad stream. This is because while send is using an extent (specially metadata) or about to read a metadata extent and expecting it belongs to a specific parent node, relocation can run, the transaction used for the relocation is committed and the extent gets reallocated while send is still using the extent, so it ends up with a different content than expected. This can result in just failing to read a metadata extent due to failure of the validation checks (parent transid, level, etc), failure to find a backreference for a data extent, and other unexpected failures. Besides reallocation, there's also a similar problem of an extent getting discarded when it's unpinned after the transaction used for block group relocation is committed. The restriction between balance and send was added in commit 9e967495e0e0 ("Btrfs: prevent send failures and crashes due to concurrent relocation"), kernel 5.3, while the more general restriction between send and relocation was added in commit 1cea5cf0e664 ("btrfs: ensure relocation never runs while we have send operations running"), kernel 5.14. Both send and relocation can be very long running operations. Relocation because it has to do a lot of IO and expensive backreference lookups in case there are many snapshots, and send due to read IO when operating on very large trees. This makes it inconvenient for users and tools to deal with scheduling both operations. For zoned filesystem we also have automatic block group relocation, so send can fail with -EAGAIN when users least expect it or send can end up delaying the block group relocation for too long. In the future we might also get the automatic block group relocation for non zoned filesystems. This change makes it possible for send and relocation to run in parallel. This is achieved the following way: 1) For all tree searches, send acquires a read lock on the commit root semaphore; 2) After each tree search, and before releasing the commit root semaphore, the leaf is cloned and placed in the search path (struct btrfs_path); 3) After releasing the commit root semaphore, the changed_cb() callback is invoked, which operates on the leaf and writes commands to the pipe (or file in case send/receive is not used with a pipe). It's important here to not hold a lock on the commit root semaphore, because if we did we could deadlock when sending and receiving to the same filesystem using a pipe - the send task blocks on the pipe because it's full, the receive task, which is the only consumer of the pipe, triggers a transaction commit when attempting to create a subvolume or reserve space for a write operation for example, but the transaction commit blocks trying to write lock the commit root semaphore, resulting in a deadlock; 4) Before moving to the next key, or advancing to the next change in case of an incremental send, check if a transaction used for relocation was committed (or is about to finish its commit). If so, release the search path(s) and restart the search, to where we were before, so that we don't operate on stale extent buffers. The search restarts are always possible because both the send and parent roots are RO, and no one can add, remove of update keys (change their offset) in RO trees - the only exception is deduplication, but that is still not allowed to run in parallel with send; 5) Periodically check if there is contention on the commit root semaphore, which means there is a transaction commit trying to write lock it, and release the semaphore and reschedule if there is contention, so as to avoid causing any significant delays to transaction commits. This leaves some room for optimizations for send to have less path releases and re searching the trees when there's relocation running, but for now it's kept simple as it performs quite well (on very large trees with resulting send streams in the order of a few hundred gigabytes). Test case btrfs/187, from fstests, stresses relocation, send and deduplication attempting to run in parallel, but without verifying if send succeeds and if it produces correct streams. A new test case will be added that exercises relocation happening in parallel with send and then checks that send succeeds and the resulting streams are correct. A final note is that for now this still leaves the mutual exclusion between send operations and deduplication on files belonging to a root used by send operations. A solution for that will be slightly more complex but it will eventually be built on top of this change. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08btrfs: do not start relocation until in progress drops are doneJosef Bacik1-0/+10
commit b4be6aefa73c9a6899ef3ba9c5faaa8a66e333ef upstream. We hit a bug with a recovering relocation on mount for one of our file systems in production. I reproduced this locally by injecting errors into snapshot delete with balance running at the same time. This presented as an error while looking up an extent item WARNING: CPU: 5 PID: 1501 at fs/btrfs/extent-tree.c:866 lookup_inline_extent_backref+0x647/0x680 CPU: 5 PID: 1501 Comm: btrfs-balance Not tainted 5.16.0-rc8+ #8 RIP: 0010:lookup_inline_extent_backref+0x647/0x680 RSP: 0018:ffffae0a023ab960 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000000 RBP: ffff943fd2a39b60 R08: 0000000000000000 R09: 0000000000000001 R10: 0001434088152de0 R11: 0000000000000000 R12: 0000000001d05000 R13: ffff943fd2a39b60 R14: ffff943fdb96f2a0 R15: ffff9442fc923000 FS: 0000000000000000(0000) GS:ffff944e9eb40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1157b1fca8 CR3: 000000010f092000 CR4: 0000000000350ee0 Call Trace: <TASK> insert_inline_extent_backref+0x46/0xd0 __btrfs_inc_extent_ref.isra.0+0x5f/0x200 ? btrfs_merge_delayed_refs+0x164/0x190 __btrfs_run_delayed_refs+0x561/0xfa0 ? btrfs_search_slot+0x7b4/0xb30 ? btrfs_update_root+0x1a9/0x2c0 btrfs_run_delayed_refs+0x73/0x1f0 ? btrfs_update_root+0x1a9/0x2c0 btrfs_commit_transaction+0x50/0xa50 ? btrfs_update_reloc_root+0x122/0x220 prepare_to_merge+0x29f/0x320 relocate_block_group+0x2b8/0x550 btrfs_relocate_block_group+0x1a6/0x350 btrfs_relocate_chunk+0x27/0xe0 btrfs_balance+0x777/0xe60 balance_kthread+0x35/0x50 ? btrfs_balance+0xe60/0xe60 kthread+0x16b/0x190 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x22/0x30 </TASK> Normally snapshot deletion and relocation are excluded from running at the same time by the fs_info->cleaner_mutex. However if we had a pending balance waiting to get the ->cleaner_mutex, and a snapshot deletion was running, and then the box crashed, we would come up in a state where we have a half deleted snapshot. Again, in the normal case the snapshot deletion needs to complete before relocation can start, but in this case relocation could very well start before the snapshot deletion completes, as we simply add the root to the dead roots list and wait for the next time the cleaner runs to clean up the snapshot. Fix this by setting a bit on the fs_info if we have any DEAD_ROOT's that had a pending drop_progress key. If they do then we know we were in the middle of the drop operation and set a flag on the fs_info. Then balance can wait until this flag is cleared to start up again. If there are DEAD_ROOT's that don't have a drop_progress set then we're safe to start balance right away as we'll be properly protected by the cleaner_mutex. CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-21btrfs: zoned: add a dedicated data relocation block groupJohannes Thumshirn1-0/+7
commit c2707a25562343511bf9a3a6a636a16a822204eb upstream Relocation in a zoned filesystem can fail with a transaction abort with error -22 (EINVAL). This happens because the relocation code assumes that the extents we relocated the data to have the same size the source extents had and ensures this by preallocating the extents. But in a zoned filesystem we currently can't preallocate the extents as this would break the sequential write required rule. Therefore it can happen that the writeback process kicks in while we're still adding pages to a delalloc range and starts writing out dirty pages. This then creates destination extents that are smaller than the source extents, triggering the following safety check in get_new_location(): 1034 if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { 1035 ret = -EINVAL; 1036 goto out; 1037 } Temporarily create a dedicated block group for the relocation process, so no non-relocation data writes can interfere with the relocation writes. This is needed that we can switch the relocation process on a zoned filesystem from the REQ_OP_ZONE_APPEND writing we use for data to a scheme like in a non-zoned filesystem using REQ_OP_WRITE and preallocation. Fixes: 32430c614844 ("btrfs: zoned: enable relocation on a zoned filesystem") Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-21btrfs: introduce btrfs_is_data_reloc_rootJohannes Thumshirn1-0/+5
commit 37f00a6d2e9c97d6e7b5c3d47c49b714c3d0b99f upstream There are several places in our codebase where we check if a root is the root of the data reloc tree and subsequent patches will introduce more. Factor out the check into a small helper function instead of open coding it multiple times. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-12Merge tag 'for-5.15-rc5-tag' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few more error handling fixes, stemming from code inspection, error injection or fuzzing" * tag 'for-5.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix abort logic in btrfs_replace_file_extents btrfs: check for error when looking up inode during dir entry replay btrfs: unify lookup return value when dir entry is missing btrfs: deal with errors when adding inode reference during log replay btrfs: deal with errors when replaying dir entry during log replay btrfs: deal with errors when checking if a dir entry exists during log replay btrfs: update refs for any root except tree log roots btrfs: unlock newly allocated extent buffer after error
2021-10-07btrfs: unify lookup return value when dir entry is missingFilipe Manana1-1/+1
btrfs_lookup_dir_index_item() and btrfs_lookup_dir_item() lookup for dir entries and both are used during log replay or when updating a log tree during an unlink. However when the dir item does not exists, btrfs_lookup_dir_item() returns NULL while btrfs_lookup_dir_index_item() returns PTR_ERR(-ENOENT), and if the dir item exists but there is no matching entry for a given name or index, both return NULL. This makes the call sites during log replay to be more verbose than necessary and it makes it easy to miss this slight difference. Since we don't need to distinguish between those two cases, make btrfs_lookup_dir_index_item() always return NULL when there is no matching directory entry - either because there isn't any dir entry or because there is one but it does not match the given name and index. Also rename the argument 'objectid' of btrfs_lookup_dir_index_item() to 'index' since it is supposed to match an index number, and the name 'objectid' is not very good because it can easily be confused with an inode number (like the inode number a dir entry points to). CC: stable@vger.kernel.org # 4.14+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-09-02Merge tag 'ovl-update-5.15' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs update from Miklos Szeredi: - Copy up immutable/append/sync/noatime attributes (Amir Goldstein) - Improve performance by enabling RCU lookup. - Misc fixes and improvements The reason this touches so many files is that the ->get_acl() method now gets a "bool rcu" argument. The ->get_acl() API was updated based on comments from Al and Linus: Link: https://lore.kernel.org/linux-fsdevel/CAJfpeguQxpd6Wgc0Jd3ks77zcsAv_bn0q17L3VNnnmPKu11t8A@mail.gmail.com/ * tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: enable RCU'd ->get_acl() vfs: add rcu argument to ->get_acl() callback ovl: fix BUG_ON() in may_delete() when called from ovl_cleanup() ovl: use kvalloc in xattr copy-up ovl: update ctime when changing fileattr ovl: skip checking lower file's i_writecount on truncate ovl: relax lookup error on mismatch origin ftype ovl: do not set overlay.opaque for new directories ovl: add ovl_allow_offline_changes() helper ovl: disable decoding null uuid with redirect_dir ovl: consistent behavior for immutable/append-only inodes ovl: copy up sync/noatime fileattr flags ovl: pass ovl_fs to ovl_check_setxattr() fs: add generic helper for filling statx attribute flags
2021-08-23btrfs: allow idmapped SNAP_CREATE/SUBVOL_CREATE ioctlsChristian Brauner1-1/+2
Creating subvolumes and snapshots is one of the core features of btrfs and is even available to unprivileged users. Make it possible to use subvolume and snapshot creation on idmapped mounts. This is a fairly straightforward operation since all the permission checking helpers are already capable of handling idmapped mounts. So we just need to pass down the mount's userns. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: introduce btrfs_search_backwards functionMarcos Paulo de Souza1-0/+4
It's a common practice to start a search using offset (u64)-1, which is the u64 maximum value, meaning that we want the search_slot function to be set in the last item with the same objectid and type. Once we are in this position, it's a matter to start a search backwards by calling btrfs_previous_item, which will check if we'll need to go to a previous leaf and other necessary checks, only to be sure that we are in last offset of the same object and type. The new btrfs_search_backwards function does the all these steps when necessary, and can be used to avoid code duplication. Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: initial fsverity supportBoris Burkov1-2/+29
Add support for fsverity in btrfs. To support the generic interface in fs/verity, we add two new item types in the fs tree for inodes with verity enabled. One stores the per-file verity descriptor and btrfs verity item and the other stores the Merkle tree data itself. Verity checking is done in end_page_read just before a page is marked uptodate. This naturally handles a variety of edge cases like holes, preallocated extents, and inline extents. Some care needs to be taken to not try to verity pages past the end of the file, which are accessed by the generic buffered file reading code under some circumstances like reading to the end of the last page and trying to read again. Direct IO on a verity file falls back to buffered reads. Verity relies on PageChecked for the Merkle tree data itself to avoid re-walking up shared paths in the tree. For this reason, we need to cache the Merkle tree data. Since the file is immutable after verity is turned on, we can cache it at an index past EOF. Use the new inode ro_flags to store verity on the inode item, so that we can enable verity on a file, then rollback to an older kernel and still mount the file system and read the file. Since we can't safely write the file anymore without ruining the invariants of the Merkle tree, we mark a ro_compat flag on the file system when a file has verity enabled. Acked-by: Eric Biggers <ebiggers@google.com> Co-developed-by: Chris Mason <clm@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: add ro compat flags to inodesBoris Burkov1-14/+16
Currently, inode flags are fully backwards incompatible in btrfs. If we introduce a new inode flag, then tree-checker will detect it and fail. This can even cause us to fail to mount entirely. To make it possible to introduce new flags which can be read-only compatible, like VERITY, we add new ro flags to btrfs without treating them quite so harshly in tree-checker. A read-only file system can survive an unexpected flag, and can be mounted. As for the implementation, it unfortunately gets a little complicated. The on-disk representation of the inode, btrfs_inode_item, has an __le64 for flags but the in-memory representation, btrfs_inode, uses a u32. David Sterba had the nice idea that we could reclaim those wasted 32 bits on disk and use them for the new ro_compat flags. It turns out that the tree-checker code which checks for unknown flags is broken, and ignores the upper 32 bits we are hoping to use. The issue is that the flags use the literal 1 rather than 1ULL, so the flags are signed ints, and one of them is specifically (1 << 31). As a result, the mask which ORs the flags is a negative integer on machines where int is 32 bit twos complement. When tree-checker evaluates the expression: btrfs_inode_flags(leaf, iitem) & ~BTRFS_INODE_FLAG_MASK) The mask is something like 0x80000abc, which gets promoted to u64 with sign extension to 0xffffffff80000abc. Negating that 64 bit mask leaves all the upper bits zeroed, and we can't detect unexpected flags. This suggests that we can't use those bits after all. Luckily, we have good reason to believe that they are zero anyway. Inode flags are metadata, which is always checksummed, so any bit flips that would introduce 1s would cause a checksum failure anyway (excluding the improbable case of the checksum getting corrupted exactly badly). Further, unless the 1 << 31 flag is used, the cast to u64 of the 32 bit inode flag should preserve its value and not add leading zeroes (at least for twos complement). The only place that flag (BTRFS_INODE_ROOT_ITEM_INIT) is used is in a special inode embedded in the root item, and indeed for that inode we see 0xffffffff80000000 as the flags on disk. However, that inode is never seen by tree checker, nor is it used in a context where verity might be meaningful. Theoretically, a future ro flag might cause trouble on that inode, so we should proactively clean up that mess before it does. With the introduction of the new ro flags, keep two separate unsigned masks and check them against the appropriate u32. Since we no longer run afoul of sign extension, this also stops writing out 0xffffffff80000000 in root_item inodes going forward. Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: use delalloc_bytes to determine flush amount for shrink_delallocJosef Bacik1-4/+5
We have been hitting some early ENOSPC issues in production with more recent kernels, and I tracked it down to us simply not flushing delalloc as aggressively as we should be. With tracing I was seeing us failing all tickets with all of the block rsvs at or around 0, with very little pinned space, but still around 120MiB of outstanding bytes_may_used. Upon further investigation I saw that we were flushing around 14 pages per shrink call for delalloc, despite having around 2GiB of delalloc outstanding. Consider the example of a 8 way machine, all CPUs trying to create a file in parallel, which at the time of this commit requires 5 items to do. Assuming a 16k leaf size, we have 10MiB of total metadata reclaim size waiting on reservations. Now assume we have 128MiB of delalloc outstanding. With our current math we would set items to 20, and then set to_reclaim to 20 * 256k, or 5MiB. Assuming that we went through this loop all 3 times, for both FLUSH_DELALLOC and FLUSH_DELALLOC_WAIT, and then did the full loop twice, we'd only flush 60MiB of the 128MiB delalloc space. This could leave a fair bit of delalloc reservations still hanging around by the time we go to ENOSPC out all the remaining tickets. Fix this two ways. First, change the calculations to be a fraction of the total delalloc bytes on the system. Prior to this change we were calculating based on dirty inodes so our math made more sense, now it's just completely unrelated to what we're actually doing. Second add a FLUSH_DELALLOC_FULL state, that we hold off until we've gone through the flush states at least once. This will empty the system of all delalloc so we're sure to be truly out of space when we start failing tickets. I'm tagging stable 5.10 and forward, because this is where we started using the page stuff heavily again. This affects earlier kernel versions as well, but would be a pain to backport to them as the flushing mechanisms aren't the same. CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: make btrfs_next_leaf static inlineDavid Sterba1-1/+12
btrfs_next_leaf is a simple wrapper for btrfs_next_old_leaf so move it to header to avoid the function call overhead. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: switch uptodate to bool in btrfs_writepage_endio_finish_orderedDavid Sterba1-1/+1
The uptodate parameter should be bool, change the type. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: remove unused start and end parameters from btrfs_run_delalloc_range()Qu Wenruo1-1/+1
Since commit d75855b4518b ("btrfs: Remove extent_io_ops::writepage_start_hook") removes the writepage_start_hook() and adds btrfs_writepage_cow_fixup() function, there is no need to follow the old hook parameters. Remove the @start and @end hook, since currently the fixup check is full page check, it doesn't need @start and @end hook. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: zoned: remove max_zone_append_size logicJohannes Thumshirn1-2/+0
There used to be a patch in the original series for zoned support which limited the extent size to max_zone_append_size, but this patch has been dropped somewhere around v9. We've decided to go the opposite direction, instead of limiting extents in the first place we split them before submission to comply with the device's limits. Remove the related code, btrfs_fs_info::max_zone_append_size and btrfs_zoned_device_info::max_zone_append_size. This also removes the workaround for dm-crypt introduced in 1d68128c107a ("btrfs: zoned: fail mount if the device does not support zone append") because the fix has been merged as f34ee1dce642 ("dm crypt: Fix zoned block device support"). Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-18vfs: add rcu argument to ->get_acl() callbackMiklos Szeredi1-1/+1
Add a rcu argument to the ->get_acl() callback to allow get_cached_acl_rcu() to call the ->get_acl() method in the next patch. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2021-06-22btrfs: remove unused btrfs_fs_info::total_pinnedNikolay Borisov1-2/+0
This got added 14 years ago in 324ae4df00fd ("Btrfs: Add block group pinned accounting back") but it was not ever used. Subsequently its usage got gradually removed in 8790d502e440 ("Btrfs: Add support for mirroring across drives") and 11833d66be94 ("Btrfs: improve async block group caching"). Let's remove it for good! 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>
2021-06-22btrfs: rip out may_commit_transactionJosef Bacik1-1/+0
may_commit_transaction was introduced before the ticketing infrastructure existed. There was a problem where we'd legitimately be out of space, but every reservation would trigger a transaction commit and then fail. Thus if you had 1000 things trying to make a reservation, they'd all do the flushing loop and thus commit the transaction 1000 times before they'd get their ENOSPC. This helper was introduced to short circuit this, if there wasn't space that could be reclaimed by committing the transaction then simply ENOSPC out. This made true ENOSPC tests much faster as we didn't waste a bunch of time. However many of our bugs over the years have been from cases where we didn't account for some space that would be reclaimed by committing a transaction. The delayed refs rsv space, delayed rsv, many pinned bytes miscalculations, etc. And in the meantime the original problem has been solved with ticketing. We no longer will commit the transaction 1000 times. Instead we'll get 1000 waiters, we will go through the flushing mechanisms, and if there's no progress after 2 loops we ENOSPC everybody out. The ticketing infrastructure gives us a deterministic way to see if we're making progress or not, thus we avoid a lot of extra work. So simplify this step by simply unconditionally committing the transaction. This removes what is arguably our most common source of early ENOSPC bugs and will allow us to drastically simplify many of the things we track because we simply won't need them with this stuff gone. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22btrfs: ensure relocation never runs while we have send operations runningFilipe Manana1-2/+3
Relocation and send do not play well together because while send is running a block group can be relocated, a transaction committed and the respective disk extents get re-allocated and written to or discarded while send is about to do something with the extents. This was explained in commit 9e967495e0e0ae ("Btrfs: prevent send failures and crashes due to concurrent relocation"), which prevented balance and send from running in parallel but it did not address one remaining case where chunk relocation can happen: shrinking a device (and device deletion which shrinks a device's size to 0 before deleting the device). We also have now one more case where relocation is triggered: on zoned filesystems partially used block groups get relocated by a background thread, introduced in commit 18bb8bbf13c183 ("btrfs: zoned: automatically reclaim zones"). So make sure that instead of preventing balance from running when there are ongoing send operations, we prevent relocation from happening. This uses the infrastructure recently added by a patch that has the subject: "btrfs: add cancellable chunk relocation support". Also it adds a spinlock used exclusively for the exclusivity between send and relocation, as before fs_info->balance_mutex was used, which would make an attempt to run send to block waiting for balance to finish, which can take a lot of time on large filesystems. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22btrfs: shorten integrity checker extent data mount optionDavid Sterba1-1/+1
Subjectively, CHECK_INTEGRITY_INCLUDING_EXTENT_DATA is quite long and calling it CHECK_INTEGRITY_DATA still keeps the meaning and matches the mount option name. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22btrfs: switch mount option bits to enums and use wider typeDavid Sterba1-32/+33
Switch defines of BTRFS_MOUNT_* to an enum (the symbolic names are recorded in the debugging information for convenience). There are two more things done but separating them would not make much sense as it's touching the same lines: - Renumber shifts 18..31 to 17..30 to get rid of the hole in the sequence. - Use 1UL as the value that gets shifted because we're approaching the 32bit limit and due to integer promotions the value of (1 << 31) becomes 0xffffffff80000000 when cast to unsigned long (eg. the option manipulating helpers). This is not causing any problems yet as the operations are in-memory and masking the 31st bit works, we don't have more than 31 bits so the ill effects of not masking higher bits don't happen. But once we have more, the problems will emerge. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22btrfs: fix typos in commentsDavid Sterba1-3/+3
Fix typos that have snuck in since the last round. Found by codespell. Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make btrfs_set_range_writeback() subpage compatibleQu Wenruo1-1/+1
Function btrfs_set_range_writeback() currently just sets the page writeback unconditionally. Change it to call the subpage helper so that we can handle both cases well. Since the subpage helpers needs btrfs_fs_info, also change the parameter to accept btrfs_inode. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: rename PagePrivate2 to PageOrdered inside btrfsQu Wenruo1-0/+10
Inside btrfs we use Private2 page status to indicate we have an ordered extent with pending IO for the sector. But the page status name, Private2, tells us nothing about the bit itself, so this patch will rename it to Ordered. And with extra comment about the bit added, so reader who is still uncertain about the page Ordered status, will find the comment pretty easily. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: pass btrfs_inode to btrfs_writepage_endio_finish_ordered()Qu Wenruo1-1/+2
There is a pretty bad abuse of btrfs_writepage_endio_finish_ordered() in end_compressed_bio_write(). It passes compressed pages to btrfs_writepage_endio_finish_ordered(), which is only supposed to accept inode pages. Thankfully the important info here is the inode, so let's pass btrfs_inode directly into btrfs_writepage_endio_finish_ordered(), and make @page parameter optional. By this, end_compressed_bio_write() can happily pass page=NULL while still getting everything done properly. Also, to cooperate with such modification, replace @page parameter for trace_btrfs_writepage_end_io_hook() with btrfs_inode. Although this removes page_index info, the existing start/len should be enough for most usage. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: refactor submit_extent_page() to make bio and its flag tracing easierQu Wenruo1-2/+0
There is a lot of code inside extent_io.c needs both "struct bio **bio_ret" and "unsigned long prev_bio_flags", along with some parameters like "unsigned long bio_flags". Such strange parameters are here for bio assembly. For example, we have such inode page layout: 0 4K 8K 12K |<-- Extent A-->|<- EB->| Then what we do is: - Page [0, 4K) *bio_ret = NULL So we allocate a new bio to bio_ret, Add page [0, 4K) to *bio_ret. - Page [4K, 8K) *bio_ret != NULL We found this page is continuous to *bio_ret, and if we're not at stripe boundary, we add page [4K, 8K) to *bio_ret. - Page [8K, 12K) *bio_ret != NULL But we found this page is not continuous, so we submit *bio_ret, then allocate a new bio, and add page [8K, 12K) to the new bio. This means we need to record both the bio and its bio_flag, but we record them manually using those strange parameter list, other than encapsulating them into their own structure. So this patch will introduce a new structure, btrfs_bio_ctrl, to record both the bio, and its bio_flags. Also, in above case, for all pages added to the bio, we need to check if the new page crosses stripe boundary. This check itself can be time consuming, and we don't really need to do that for each page. This patch also integrates the stripe boundary check into btrfs_bio_ctrl. When a new bio is allocated, the stripe and ordered extent boundary is also calculated, so no matter how large the bio will be, we only calculate the boundaries once, to save some CPU time. The following functions/structures are affected: - struct extent_page_data Replace its bio pointer with structure btrfs_bio_ctrl (embedded structure, not pointer) - end_write_bio() - flush_write_bio() Just change how bio is fetched - btrfs_bio_add_page() Use pre-calculated boundaries instead of re-calculating them. And use @bio_ctrl to replace @bio and @prev_bio_flags. - calc_bio_boundaries() New function - submit_extent_page() callers - btrfs_do_readpage() callers - contiguous_readpages() callers To Use @bio_ctrl to replace @bio and @prev_bio_flags, and how to grab bio. - btrfs_bio_fits_in_ordered_extent() Removed, as now the ordered extent size limit is done at bio allocation time, no need to check for each page range. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: introduce try-lock semantics for exclusive op startDavid Sterba1-0/+3
Add try-lock for exclusive operation start to allow callers to do more checks. The same operation must already be running. The try-lock and unlock must pair and are a substitute for btrfs_exclop_start, thus it must also pair with btrfs_exclop_finish to release the exclop context. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: add cancellable chunk relocation supportDavid Sterba1-0/+9
Add support code that will allow canceling relocation on the chunk granularity. This is different and independent of balance, that also uses relocation but is a higher level operation and manages it's own state and pause/cancellation requests. Relocation is used for resize (shrink) and device deletion so this will be a common point to implement cancellation for both. The context is entirely in btrfs_relocate_block_group and btrfs_recover_relocation, enclosing one chunk relocation. The status bit is set and unset between the chunks. As relocation can take long, the effects may not be immediate and the request and actual action can slightly race. The fs_info::reloc_cancel_req is only supposed to be increased and does not pair with decrement like fs_info::balance_cancel_req. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: protect exclusive_operation by super_lockDavid Sterba1-2/+2
The exclusive operation is now atomically checked and set using bit operations. Switch it to protection by spinlock. The super block lock is not frequently used and adding a new lock seems like an overkill so it should be safe to reuse it. The reason to use spinlock is to enhance the locking context so more checks can be done, eg. allowing the same exclusive operation enter the exclop section and cancel the running one. This will be used for resize and device delete. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: document byte swap optimization of root_item::flags accessorsDavid Sterba1-0/+2
Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: don't set the full sync flag when truncation does not touch extentsFilipe Manana1-1/+1
At btrfs_truncate() where we truncate the inode either to the same size or to a smaller size, we always set the full sync flag on the inode. This is needed in case the truncation drops or trims any file extent items that start beyond or cross the new inode size, so that the next fsync drops all inode items from the log and scans again the fs/subvolume tree to find all items that must be logged. However if the truncation does not drop or trims any file extent items, we do not need to set the full sync flag and force the next fsync to use the slow code path. So do not set the full sync flag in such cases. One use case where it is frequent to do truncations that do not change the inode size and do not drop any extents (no prealloc extents beyond i_size) is when running Microsoft's SQL Server inside a Docker container. One example workload is the one Philipp Fent reported recently, in the thread with a link below. In this workload a large number of fsyncs are preceded by such truncate operations. After this change I constantly get the runtime for that workload from Philipp to be reduced by about -12%, for example from 184 seconds down to 162 seconds. Link: https://lore.kernel.org/linux-btrfs/93c4600e-5263-5cba-adf0-6f47526e7561@in.tum.de/ Tested-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make btrfs_verify_data_csum() to return a bitmapQu Wenruo1-2/+2
This will provide the basis for later per-sector repair for subpage, while still keeping the existing code happy. As if all csums match, the return value will be 0, same as now. Only when csum mismatches, the return value is different. The new return value will be a bitmap, for 4K sectorsize and 4K page size, it will be either 1, instead of the -EIO (which is not used directly by the callers, no effective change). But for 4K sectorsize and 64K page size, aka subpage case, since the bvec can contain multiple sectors, knowing which sectors are corrupted will allow us to submit repair only for corrupted sectors. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-11Merge tag 'for-5.13-rc1-tag' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "First batch of various fixes, here's a list of notable ones: - fix unmountable seed device after fstrim - fix silent data loss in zoned mode due to ordered extent splitting - fix race leading to unpersisted data and metadata on fsync - fix deadlock when cloning inline extents and using qgroups" * tag 'for-5.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: initialize return variable in cleanup_free_space_cache_v1 btrfs: zoned: sanity check zone type btrfs: fix unmountable seed device after fstrim btrfs: fix deadlock when cloning inline extents and using qgroups btrfs: fix race leading to unpersisted data and metadata on fsync btrfs: do not consider send context as valid when trying to flush qgroups btrfs: zoned: fix silent data loss after failure splitting ordered extent
2021-04-28btrfs: fix deadlock when cloning inline extents and using qgroupsFilipe Manana1-1/+1
There are a few exceptional cases where cloning an inline extent needs to copy the inline extent data into a page of the destination inode. When this happens, we end up starting a transaction while having a dirty page for the destination inode and while having the range locked in the destination's inode iotree too. Because when reserving metadata space for a transaction we may need to flush existing delalloc in case there is not enough free space, we have a mechanism in place to prevent a deadlock, which was introduced in commit 3d45f221ce627d ("btrfs: fix deadlock when cloning inline extent and low on free metadata space"). However when using qgroups, a transaction also reserves metadata qgroup space, which can also result in flushing delalloc in case there is not enough available space at the moment. When this happens we deadlock, since flushing delalloc requires locking the file range in the inode's iotree and the range was already locked at the very beginning of the clone operation, before attempting to start the transaction. When this issue happens, stack traces like the following are reported: [72747.556262] task:kworker/u81:9 state:D stack: 0 pid: 225 ppid: 2 flags:0x00004000 [72747.556268] Workqueue: writeback wb_workfn (flush-btrfs-1142) [72747.556271] Call Trace: [72747.556273] __schedule+0x296/0x760 [72747.556277] schedule+0x3c/0xa0 [72747.556279] io_schedule+0x12/0x40 [72747.556284] __lock_page+0x13c/0x280 [72747.556287] ? generic_file_readonly_mmap+0x70/0x70 [72747.556325] extent_write_cache_pages+0x22a/0x440 [btrfs] [72747.556331] ? __set_page_dirty_nobuffers+0xe7/0x160 [72747.556358] ? set_extent_buffer_dirty+0x5e/0x80 [btrfs] [72747.556362] ? update_group_capacity+0x25/0x210 [72747.556366] ? cpumask_next_and+0x1a/0x20 [72747.556391] extent_writepages+0x44/0xa0 [btrfs] [72747.556394] do_writepages+0x41/0xd0 [72747.556398] __writeback_single_inode+0x39/0x2a0 [72747.556403] writeback_sb_inodes+0x1ea/0x440 [72747.556407] __writeback_inodes_wb+0x5f/0xc0 [72747.556410] wb_writeback+0x235/0x2b0 [72747.556414] ? get_nr_inodes+0x35/0x50 [72747.556417] wb_workfn+0x354/0x490 [72747.556420] ? newidle_balance+0x2c5/0x3e0 [72747.556424] process_one_work+0x1aa/0x340 [72747.556426] worker_thread+0x30/0x390 [72747.556429] ? create_worker+0x1a0/0x1a0 [72747.556432] kthread+0x116/0x130 [72747.556435] ? kthread_park+0x80/0x80 [72747.556438] ret_from_fork+0x1f/0x30 [72747.566958] Workqueue: btrfs-flush_delalloc btrfs_work_helper [btrfs] [72747.566961] Call Trace: [72747.566964] __schedule+0x296/0x760 [72747.566968] ? finish_wait+0x80/0x80 [72747.566970] schedule+0x3c/0xa0 [72747.566995] wait_extent_bit.constprop.68+0x13b/0x1c0 [btrfs] [72747.566999] ? finish_wait+0x80/0x80 [72747.567024] lock_extent_bits+0x37/0x90 [btrfs] [72747.567047] btrfs_invalidatepage+0x299/0x2c0 [btrfs] [72747.567051] ? find_get_pages_range_tag+0x2cd/0x380 [72747.567076] __extent_writepage+0x203/0x320 [btrfs] [72747.567102] extent_write_cache_pages+0x2bb/0x440 [btrfs] [72747.567106] ? update_load_avg+0x7e/0x5f0 [72747.567109] ? enqueue_entity+0xf4/0x6f0 [72747.567134] extent_writepages+0x44/0xa0 [btrfs] [72747.567137] ? enqueue_task_fair+0x93/0x6f0 [72747.567140] do_writepages+0x41/0xd0 [72747.567144] __filemap_fdatawrite_range+0xc7/0x100 [72747.567167] btrfs_run_delalloc_work+0x17/0x40 [btrfs] [72747.567195] btrfs_work_helper+0xc2/0x300 [btrfs] [72747.567200] process_one_work+0x1aa/0x340 [72747.567202] worker_thread+0x30/0x390 [72747.567205] ? create_worker+0x1a0/0x1a0 [72747.567208] kthread+0x116/0x130 [72747.567211] ? kthread_park+0x80/0x80 [72747.567214] ret_from_fork+0x1f/0x30 [72747.569686] task:fsstress state:D stack: 0 pid:841421 ppid:841417 flags:0x00000000 [72747.569689] Call Trace: [72747.569691] __schedule+0x296/0x760 [72747.569694] schedule+0x3c/0xa0 [72747.569721] try_flush_qgroup+0x95/0x140 [btrfs] [72747.569725] ? finish_wait+0x80/0x80 [72747.569753] btrfs_qgroup_reserve_data+0x34/0x50 [btrfs] [72747.569781] btrfs_check_data_free_space+0x5f/0xa0 [btrfs] [72747.569804] btrfs_buffered_write+0x1f7/0x7f0 [btrfs] [72747.569810] ? path_lookupat.isra.48+0x97/0x140 [72747.569833] btrfs_file_write_iter+0x81/0x410 [btrfs] [72747.569836] ? __kmalloc+0x16a/0x2c0 [72747.569839] do_iter_readv_writev+0x160/0x1c0 [72747.569843] do_iter_write+0x80/0x1b0 [72747.569847] vfs_writev+0x84/0x140 [72747.569869] ? btrfs_file_llseek+0x38/0x270 [btrfs] [72747.569873] do_writev+0x65/0x100 [72747.569876] do_syscall_64+0x33/0x40 [72747.569879] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [72747.569899] task:fsstress state:D stack: 0 pid:841424 ppid:841417 flags:0x00004000 [72747.569903] Call Trace: [72747.569906] __schedule+0x296/0x760 [72747.569909] schedule+0x3c/0xa0 [72747.569936] try_flush_qgroup+0x95/0x140 [btrfs] [72747.569940] ? finish_wait+0x80/0x80 [72747.569967] __btrfs_qgroup_reserve_meta+0x36/0x50 [btrfs] [72747.569989] start_transaction+0x279/0x580 [btrfs] [72747.570014] clone_copy_inline_extent+0x332/0x490 [btrfs] [72747.570041] btrfs_clone+0x5b7/0x7a0 [btrfs] [72747.570068] ? lock_extent_bits+0x64/0x90 [btrfs] [72747.570095] btrfs_clone_files+0xfc/0x150 [btrfs] [72747.570122] btrfs_remap_file_range+0x3d8/0x4a0 [btrfs] [72747.570126] do_clone_file_range+0xed/0x200 [72747.570131] vfs_clone_file_range+0x37/0x110 [72747.570134] ioctl_file_clone+0x7d/0xb0 [72747.570137] do_vfs_ioctl+0x138/0x630 [72747.570140] __x64_sys_ioctl+0x62/0xc0 [72747.570143] do_syscall_64+0x33/0x40 [72747.570146] entry_SYSCALL_64_after_hwframe+0x44/0xa9 So fix this by skipping the flush of delalloc for an inode that is flagged with BTRFS_INODE_NO_DELALLOC_FLUSH, meaning it is currently under such a special case of cloning an inline extent, when flushing delalloc during qgroup metadata reservation. The special cases for cloning inline extents were added in kernel 5.7 by by commit 05a5a7621ce66c ("Btrfs: implement full reflink support for inline extents"), while having qgroup metadata space reservation flushing delalloc when low on space was added in kernel 5.9 by commit c53e9653605dbf ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT"). So use a "Fixes:" tag for the later commit to ease stable kernel backports. Reported-by: Wang Yugui <wangyugui@e16-tech.com> Link: https://lore.kernel.org/linux-btrfs/20210421083137.31E3.409509F4@e16-tech.com/ Fixes: c53e9653605dbf ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT") CC: stable@vger.kernel.org # 5.9+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-27Merge branch 'miklos.fileattr' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull fileattr conversion updates from Miklos Szeredi via Al Viro: "This splits the handling of FS_IOC_[GS]ETFLAGS from ->ioctl() into a separate method. The interface is reasonably uniform across the filesystems that support it and gives nice boilerplate removal" * 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits) ovl: remove unneeded ioctls fuse: convert to fileattr fuse: add internal open/release helpers fuse: unsigned open flags fuse: move ioctl to separate source file vfs: remove unused ioctl helpers ubifs: convert to fileattr reiserfs: convert to fileattr ocfs2: convert to fileattr nilfs2: convert to fileattr jfs: convert to fileattr hfsplus: convert to fileattr efivars: convert to fileattr xfs: convert to fileattr orangefs: convert to fileattr gfs2: convert to fileattr f2fs: convert to fileattr ext4: convert to fileattr ext2: convert to fileattr btrfs: convert to fileattr ...
2021-04-20btrfs: zoned: automatically reclaim zonesJohannes Thumshirn1-0/+5
When a file gets deleted on a zoned file system, the space freed is not returned back into the block group's free space, but is migrated to zone_unusable. As this zone_unusable space is behind the current write pointer it is not possible to use it for new allocations. In the current implementation a zone is reset once all of the block group's space is accounted as zone unusable. This behaviour can lead to premature ENOSPC errors on a busy file system. Instead of only reclaiming the zone once it is completely unusable, kick off a reclaim job once the amount of unusable bytes exceeds a user configurable threshold between 51% and 100%. It can be set per mounted filesystem via the sysfs tunable bg_reclaim_threshold which is set to 75% by default. Similar to reclaiming unused block groups, these dirty block groups are added to a to_reclaim list and then on a transaction commit, the reclaim process is triggered but after we deleted unused block groups, which will free space for the relocation process. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: rename delete_unused_bgs_mutex to reclaim_bgs_lockJohannes Thumshirn1-1/+2
As a preparation for extending the block group deletion use case, rename the unused_bgs_mutex to reclaim_bgs_lock. Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: more graceful errors/warnings on 32bit systems when reaching limitsQu Wenruo1-0/+19
Btrfs uses internally mapped u64 address space for all its metadata. Due to the page cache limit on 32bit systems, btrfs can't access metadata at or beyond (ULONG_MAX + 1) << PAGE_SHIFT. See how MAX_LFS_FILESIZE and page::index are defined. This is 16T for 4K page size while 256T for 64K page size. Users can have a filesystem which doesn't have metadata beyond the boundary at mount time, but later balance can cause it to create metadata beyond the boundary. And modification to MM layer is unrealistic just for such minor use case. We can't do more than to prevent mounting such filesystem or warn early when the numbers are still within the limits. To address such problem, this patch will introduce the following checks: - Mount time rejection This will reject any fs which has metadata chunk at or beyond the boundary. - Mount time early warning If there is any metadata chunk beyond 5/8th of the boundary, we do an early warning and hope the end user will see it. - Runtime extent buffer rejection If we're going to allocate an extent buffer at or beyond the boundary, reject such request with EOVERFLOW. This is definitely going to cause problems like transaction abort, but we have no better ways. - Runtime extent buffer early warning If an extent buffer beyond 5/8th of the max file size is allocated, do an early warning. Above error/warning message will only be printed once for each fs to reduce dmesg flood. If the mount is rejected, the filesystem will be mountable only on a 64bit host. Link: https://lore.kernel.org/linux-btrfs/1783f16d-7a28-80e6-4c32-fdf19b705ed0@gmx.com/ Reported-by: Erik Jensen <erikjensen@rkjnsn.net> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: improve btree readahead for full send operationsFilipe Manana1-1/+21
Currently a full send operation uses the standard btree readahead when iterating over the subvolume/snapshot btree, which despite bringing good performance benefits, it could be improved in a few aspects for use cases such as full send operations, which are guaranteed to visit every node and leaf of a btree, in ascending and sequential order. The limitations of that standard btree readahead implementation are the following: 1) It only triggers readahead for leaves that are physically close to the leaf being read, within a 64K range; 2) It only triggers readahead for the next or previous leaves if the leaf being read is not currently in memory; 3) It never triggers readahead for nodes. So add a new readahead mode that addresses all these points and use it for full send operations. The following test script was used to measure the improvement on a box using an average, consumer grade, spinning disk and with 16GiB of RAM: $ cat test.sh #!/bin/bash DEV=/dev/sdj MNT=/mnt/sdj MKFS_OPTIONS="--nodesize 16384" # default, just to be explicit MOUNT_OPTIONS="-o max_inline=2048" # default, just to be explicit mkfs.btrfs -f $MKFS_OPTIONS $DEV > /dev/null mount $MOUNT_OPTIONS $DEV $MNT # Create files with inline data to make it easier and faster to create # large btrees. add_files() { local total=$1 local start_offset=$2 local number_jobs=$3 local total_per_job=$(($total / $number_jobs)) echo "Creating $total new files using $number_jobs jobs" for ((n = 0; n < $number_jobs; n++)); do ( local start_num=$(($start_offset + $n * $total_per_job)) for ((i = 1; i <= $total_per_job; i++)); do local file_num=$((start_num + $i)) local file_path="$MNT/file_${file_num}" xfs_io -f -c "pwrite -S 0xab 0 2000" $file_path > /dev/null if [ $? -ne 0 ]; then echo "Failed creating file $file_path" break fi done ) & worker_pids[$n]=$! done wait ${worker_pids[@]} sync echo echo "btree node/leaf count: $(btrfs inspect-internal dump-tree -t 5 $DEV | egrep '^(node|leaf) ' | wc -l)" } initial_file_count=500000 add_files $initial_file_count 0 4 echo echo "Creating first snapshot..." btrfs subvolume snapshot -r $MNT $MNT/snap1 echo echo "Adding more files..." add_files $((initial_file_count / 4)) $initial_file_count 4 echo echo "Updating 1/50th of the initial files..." for ((i = 1; i < $initial_file_count; i += 50)); do xfs_io -c "pwrite -S 0xcd 0 20" $MNT/file_$i > /dev/null done echo echo "Creating second snapshot..." btrfs subvolume snapshot -r $MNT $MNT/snap2 umount $MNT echo 3 > /proc/sys/vm/drop_caches blockdev --flushbufs $DEV &> /dev/null hdparm -F $DEV &> /dev/null mount $MOUNT_OPTIONS $DEV $MNT echo echo "Testing full send..." start=$(date +%s) btrfs send $MNT/snap1 > /dev/null end=$(date +%s) echo echo "Full send took $((end - start)) seconds" umount $MNT The durations of the full send operation in seconds were the following: Before this change: 217 seconds After this change: 205 seconds (-5.7%) Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: use a bit to track the existence of tree mod log usersFilipe Manana1-0/+3
The tree modification log functions are called very frequently, basically they are called every time a btree is modified (a pointer added or removed to a node, a new root for a btree is set, etc). Because of that, to avoid heavy lock contention on the lock that protects the list of tree mod log users, we have checks that test the emptiness of the list with a full memory barrier before the checks, so that when there are no tree mod log users we avoid taking the lock. Replace the memory barrier and list emptiness check with a test for a new bit set at fs_info->flags. This bit is used to indicate when there are tree mod log users, set whenever a user is added to the list and cleared when the last user is removed from the list. This makes the intention a bit more obvious and possibly more efficient (assuming test_bit() may be cheaper than a full memory barrier on some architectures). Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: move the tree mod log code into its own fileFilipe Manana1-17/+0
The tree modification log, which records modifications done to btrees, is quite large and currently spread all over ctree.c, which is a huge file already. To make things better organized, move all that code into its own separate source and header files. Functions and definitions that are used outside of the module (mostly by ctree.c) are renamed so that they start with a "btrfs_" prefix. Everything else remains unchanged. This makes it easier to go over the tree modification log code every time I need to go read it to fix a bug. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor comment updates ] Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: remove duplicated in_range() macroJohannes Thumshirn1-2/+0
The in_range() macro is defined twice in btrfs' source, once in ctree.h and once in misc.h. Remove the definition in ctree.h and include misc.h in the files depending on it. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: add a i_mmap_lock to our inodeJosef Bacik1-0/+1
We need to be able to exclude page_mkwrite from happening concurrently with certain operations. To facilitate this, add a i_mmap_lock to our inode, down_read() it in our mkwrite, and add a new ILOCK flag to indicate that we want to take the i_mmap_lock as well. I used pahole to check the size of the btrfs_inode, the sizes are as follows no lockdep: before: 1120 (3 per 4k page) after: 1160 (3 per 4k page) lockdep: before: 2072 (1 per 4k page) after: 2224 (1 per 4k page) We're slightly larger but it doesn't change how many objects we can fit per page. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: remove mirror argument from btrfs_csum_verify_data()Goldwyn Rodrigues1-1/+1
The parameter mirror is not used and does not make sense for checksum verification of the given bio. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: unexport btrfs_extent_readonly() and make it staticAnand Jain1-1/+0
btrfs_extent_readonly() is used by can_nocow_extent() in inode.c. So move it from extent-tree.c to inode.c and declare it as static. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: make btrfs_replace_file_extents take btrfs_inodeNikolay Borisov1-2/+3
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-12btrfs: convert to fileattrMiklos Szeredi1-0/+3
Use the fileattr API to let the VFS handle locking, permission checking and conversion. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: David Sterba <dsterba@suse.com>
2021-03-01Merge tag 'for-5.12-rc1-tag' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "This is the first batch of fixes that usually arrive during the merge window code freeze. Regressions and stable material. Regressions: - fix deadlock in log sync in zoned mode - fix bugs in subpage mode still wrongly assuming sectorsize == page size Fixes: - fix missing kunmap of the Q stripe in RAID6 - block group fixes: - fix race between extent freeing/allocation when using bitmaps - avoid double put of block group when emptying cluster - swapfile fixes: - fix swapfile writes vs running scrub - fix swapfile activation vs snapshot creation - fix stale data exposure after cloning a hole with NO_HOLES enabled - remove tree-checker check that does not work in case information from other leaves is necessary" * tag 'for-5.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: zoned: fix deadlock on log sync btrfs: avoid double put of block group when emptying cluster btrfs: fix stale data exposure after cloning a hole with NO_HOLES enabled btrfs: tree-checker: do not error out if extent ref hash doesn't match btrfs: fix race between swap file activation and snapshot creation btrfs: fix race between writes to swap files and scrub btrfs: avoid checking for RO block group twice during nocow writeback btrfs: fix race between extent freeing/allocation when using bitmaps btrfs: make check_compressed_csum() to be subpage compatible btrfs: make btrfs_submit_compressed_read() subpage compatible btrfs: fix raid6 qstripe kmap