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2022-09-26btrfs: add lockdep annotations for num_writers wait eventIoannis Angelakopoulos
Annotate the num_writers wait event in fs/btrfs/transaction.c with lockdep in order to catch deadlocks involving this wait event. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Ioannis Angelakopoulos <iangelak@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26btrfs: add macros for annotating wait events with lockdepIoannis Angelakopoulos
Introduce four macros that are used to annotate wait events in btrfs code with lockdep; 1) the btrfs_lockdep_init_map 2) the btrfs_lockdep_acquire, 3) the btrfs_lockdep_release 4) the btrfs_might_wait_for_event macros. The btrfs_lockdep_init_map macro is used to initialize a lockdep map. The btrfs_lockdep_<acquire,release> macros are used by threads to take the lockdep map as readers (shared lock) and release it, respectively. The btrfs_might_wait_for_event macro is used by threads to take the lockdep map as writers (exclusive lock) and release it. In general, the lockdep annotation for wait events work as follows: The condition for a wait event can be modified and signaled at the same time by multiple threads. These threads hold the lockdep map as readers when they enter a context in which blocking would prevent signaling the condition. Frequently, this occurs when a thread violates a condition (lockdep map acquire), before restoring it and signaling it at a later point (lockdep map release). The threads that block on the wait event take the lockdep map as writers (exclusive lock). These threads have to block until all the threads that hold the lockdep map as readers signal the condition for the wait event and release the lockdep map. The lockdep annotation is used to warn about potential deadlock scenarios that involve the threads that modify and signal the wait event condition and threads that block on the wait event. A simple example is illustrated below: Without lockdep: TA TB cond = false lock(A) wait_event(w, cond) unlock(A) lock(A) cond = true signal(w) unlock(A) With lockdep: TA TB rwsem_acquire_read(lockdep_map) cond = false lock(A) rwsem_acquire(lockdep_map) rwsem_release(lockdep_map) wait_event(w, cond) unlock(A) lock(A) cond = true signal(w) unlock(A) rwsem_release(lockdep_map) In the second case, with the lockdep annotation, lockdep would warn about an ABBA deadlock, while the first case would just deadlock at some point. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Ioannis Angelakopoulos <iangelak@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-05btrfs: zoned: fix API misuse of zone finish waitingNaohiro Aota
The commit 2ce543f47843 ("btrfs: zoned: wait until zone is finished when allocation didn't progress") implemented a zone finish waiting mechanism to the write path of zoned mode. However, using wait_var_event()/wake_up_all() on fs_info->zone_finish_wait is wrong and wait_var_event() just hangs because no one ever wakes it up once it goes into sleep. Instead, we can simply use wait_on_bit_io() and clear_and_wake_up_bit() on fs_info->flags with a proper barrier installed. Fixes: 2ce543f47843 ("btrfs: zoned: wait until zone is finished when allocation didn't progress") CC: stable@vger.kernel.org # 5.16+ Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-08-23btrfs: fix space cache corruption and potential double allocationsOmar Sandoval
When testing space_cache v2 on a large set of machines, we encountered a few symptoms: 1. "unable to add free space :-17" (EEXIST) errors. 2. Missing free space info items, sometimes caught with a "missing free space info for X" error. 3. Double-accounted space: ranges that were allocated in the extent tree and also marked as free in the free space tree, ranges that were marked as allocated twice in the extent tree, or ranges that were marked as free twice in the free space tree. If the latter made it onto disk, the next reboot would hit the BUG_ON() in add_new_free_space(). 4. On some hosts with no on-disk corruption or error messages, the in-memory space cache (dumped with drgn) disagreed with the free space tree. All of these symptoms have the same underlying cause: a race between caching the free space for a block group and returning free space to the in-memory space cache for pinned extents causes us to double-add a free range to the space cache. This race exists when free space is cached from the free space tree (space_cache=v2) or the extent tree (nospace_cache, or space_cache=v1 if the cache needs to be regenerated). struct btrfs_block_group::last_byte_to_unpin and struct btrfs_block_group::progress are supposed to protect against this race, but commit d0c2f4fa555e ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") subtly broke this by allowing multiple transactions to be unpinning extents at the same time. Specifically, the race is as follows: 1. An extent is deleted from an uncached block group in transaction A. 2. btrfs_commit_transaction() is called for transaction A. 3. btrfs_run_delayed_refs() -> __btrfs_free_extent() runs the delayed ref for the deleted extent. 4. __btrfs_free_extent() -> do_free_extent_accounting() -> add_to_free_space_tree() adds the deleted extent back to the free space tree. 5. do_free_extent_accounting() -> btrfs_update_block_group() -> btrfs_cache_block_group() queues up the block group to get cached. block_group->progress is set to block_group->start. 6. btrfs_commit_transaction() for transaction A calls switch_commit_roots(). It sets block_group->last_byte_to_unpin to block_group->progress, which is block_group->start because the block group hasn't been cached yet. 7. The caching thread gets to our block group. Since the commit roots were already switched, load_free_space_tree() sees the deleted extent as free and adds it to the space cache. It finishes caching and sets block_group->progress to U64_MAX. 8. btrfs_commit_transaction() advances transaction A to TRANS_STATE_SUPER_COMMITTED. 9. fsync calls btrfs_commit_transaction() for transaction B. Since transaction A is already in TRANS_STATE_SUPER_COMMITTED and the commit is for fsync, it advances. 10. btrfs_commit_transaction() for transaction B calls switch_commit_roots(). This time, the block group has already been cached, so it sets block_group->last_byte_to_unpin to U64_MAX. 11. btrfs_commit_transaction() for transaction A calls btrfs_finish_extent_commit(), which calls unpin_extent_range() for the deleted extent. It sees last_byte_to_unpin set to U64_MAX (by transaction B!), so it adds the deleted extent to the space cache again! This explains all of our symptoms above: * If the sequence of events is exactly as described above, when the free space is re-added in step 11, it will fail with EEXIST. * If another thread reallocates the deleted extent in between steps 7 and 11, then step 11 will silently re-add that space to the space cache as free even though it is actually allocated. Then, if that space is allocated *again*, the free space tree will be corrupted (namely, the wrong item will be deleted). * If we don't catch this free space tree corruption, it will continue to get worse as extents are deleted and reallocated. The v1 space_cache is synchronously loaded when an extent is deleted (btrfs_update_block_group() with alloc=0 calls btrfs_cache_block_group() with load_cache_only=1), so it is not normally affected by this bug. However, as noted above, if we fail to load the space cache, we will fall back to caching from the extent tree and may hit this bug. The easiest fix for this race is to also make caching from the free space tree or extent tree synchronous. Josef tested this and found no performance regressions. A few extra changes fall out of this change. Namely, this fix does the following, with step 2 being the crucial fix: 1. Factor btrfs_caching_ctl_wait_done() out of btrfs_wait_block_group_cache_done() to allow waiting on a caching_ctl that we already hold a reference to. 2. Change the call in btrfs_cache_block_group() of btrfs_wait_space_cache_v1_finished() to btrfs_caching_ctl_wait_done(), which makes us wait regardless of the space_cache option. 3. Delete the now unused btrfs_wait_space_cache_v1_finished() and space_cache_v1_done(). 4. Change btrfs_cache_block_group()'s `int load_cache_only` parameter to `bool wait` to more accurately describe its new meaning. 5. Change a few callers which had a separate call to btrfs_wait_block_group_cache_done() to use wait = true instead. 6. Make btrfs_wait_block_group_cache_done() static now that it's not used outside of block-group.c anymore. Fixes: d0c2f4fa555e ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") CC: stable@vger.kernel.org # 5.12+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-08-17btrfs: fix lockdep splat with reloc root extent buffersJosef Bacik
We have been hitting the following lockdep splat with btrfs/187 recently WARNING: possible circular locking dependency detected 5.19.0-rc8+ #775 Not tainted ------------------------------------------------------ btrfs/752500 is trying to acquire lock: ffff97e1875a97b8 (btrfs-treloc-02#2){+.+.}-{3:3}, at: __btrfs_tree_lock+0x24/0x110 but task is already holding lock: ffff97e1875a9278 (btrfs-tree-01/1){+.+.}-{3:3}, at: __btrfs_tree_lock+0x24/0x110 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (btrfs-tree-01/1){+.+.}-{3:3}: down_write_nested+0x41/0x80 __btrfs_tree_lock+0x24/0x110 btrfs_init_new_buffer+0x7d/0x2c0 btrfs_alloc_tree_block+0x120/0x3b0 __btrfs_cow_block+0x136/0x600 btrfs_cow_block+0x10b/0x230 btrfs_search_slot+0x53b/0xb70 btrfs_lookup_inode+0x2a/0xa0 __btrfs_update_delayed_inode+0x5f/0x280 btrfs_async_run_delayed_root+0x24c/0x290 btrfs_work_helper+0xf2/0x3e0 process_one_work+0x271/0x590 worker_thread+0x52/0x3b0 kthread+0xf0/0x120 ret_from_fork+0x1f/0x30 -> #1 (btrfs-tree-01){++++}-{3:3}: down_write_nested+0x41/0x80 __btrfs_tree_lock+0x24/0x110 btrfs_search_slot+0x3c3/0xb70 do_relocation+0x10c/0x6b0 relocate_tree_blocks+0x317/0x6d0 relocate_block_group+0x1f1/0x560 btrfs_relocate_block_group+0x23e/0x400 btrfs_relocate_chunk+0x4c/0x140 btrfs_balance+0x755/0xe40 btrfs_ioctl+0x1ea2/0x2c90 __x64_sys_ioctl+0x88/0xc0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (btrfs-treloc-02#2){+.+.}-{3:3}: __lock_acquire+0x1122/0x1e10 lock_acquire+0xc2/0x2d0 down_write_nested+0x41/0x80 __btrfs_tree_lock+0x24/0x110 btrfs_lock_root_node+0x31/0x50 btrfs_search_slot+0x1cb/0xb70 replace_path+0x541/0x9f0 merge_reloc_root+0x1d6/0x610 merge_reloc_roots+0xe2/0x260 relocate_block_group+0x2c8/0x560 btrfs_relocate_block_group+0x23e/0x400 btrfs_relocate_chunk+0x4c/0x140 btrfs_balance+0x755/0xe40 btrfs_ioctl+0x1ea2/0x2c90 __x64_sys_ioctl+0x88/0xc0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: btrfs-treloc-02#2 --> btrfs-tree-01 --> btrfs-tree-01/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(btrfs-tree-01/1); lock(btrfs-tree-01); lock(btrfs-tree-01/1); lock(btrfs-treloc-02#2); *** DEADLOCK *** 7 locks held by btrfs/752500: #0: ffff97e292fdf460 (sb_writers#12){.+.+}-{0:0}, at: btrfs_ioctl+0x208/0x2c90 #1: ffff97e284c02050 (&fs_info->reclaim_bgs_lock){+.+.}-{3:3}, at: btrfs_balance+0x55f/0xe40 #2: ffff97e284c00878 (&fs_info->cleaner_mutex){+.+.}-{3:3}, at: btrfs_relocate_block_group+0x236/0x400 #3: ffff97e292fdf650 (sb_internal#2){.+.+}-{0:0}, at: merge_reloc_root+0xef/0x610 #4: ffff97e284c02378 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x1a8/0x5a0 #5: ffff97e284c023a0 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x1a8/0x5a0 #6: ffff97e1875a9278 (btrfs-tree-01/1){+.+.}-{3:3}, at: __btrfs_tree_lock+0x24/0x110 stack backtrace: CPU: 1 PID: 752500 Comm: btrfs Not tainted 5.19.0-rc8+ #775 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack_lvl+0x56/0x73 check_noncircular+0xd6/0x100 ? lock_is_held_type+0xe2/0x140 __lock_acquire+0x1122/0x1e10 lock_acquire+0xc2/0x2d0 ? __btrfs_tree_lock+0x24/0x110 down_write_nested+0x41/0x80 ? __btrfs_tree_lock+0x24/0x110 __btrfs_tree_lock+0x24/0x110 btrfs_lock_root_node+0x31/0x50 btrfs_search_slot+0x1cb/0xb70 ? lock_release+0x137/0x2d0 ? _raw_spin_unlock+0x29/0x50 ? release_extent_buffer+0x128/0x180 replace_path+0x541/0x9f0 merge_reloc_root+0x1d6/0x610 merge_reloc_roots+0xe2/0x260 relocate_block_group+0x2c8/0x560 btrfs_relocate_block_group+0x23e/0x400 btrfs_relocate_chunk+0x4c/0x140 btrfs_balance+0x755/0xe40 btrfs_ioctl+0x1ea2/0x2c90 ? lock_is_held_type+0xe2/0x140 ? lock_is_held_type+0xe2/0x140 ? __x64_sys_ioctl+0x88/0xc0 __x64_sys_ioctl+0x88/0xc0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd This isn't necessarily new, it's just tricky to hit in practice. There are two competing things going on here. With relocation we create a snapshot of every fs tree with a reloc tree. Any extent buffers that get initialized here are initialized with the reloc root lockdep key. However since it is a snapshot, any blocks that are currently in cache that originally belonged to the fs tree will have the normal tree lockdep key set. This creates the lock dependency of reloc tree -> normal tree for the extent buffer locking during the first phase of the relocation as we walk down the reloc root to relocate blocks. However this is problematic because the final phase of the relocation is merging the reloc root into the original fs root. This involves searching down to any keys that exist in the original fs root and then swapping the relocated block and the original fs root block. We have to search down to the fs root first, and then go search the reloc root for the block we need to replace. This creates the dependency of normal tree -> reloc tree which is why lockdep complains. Additionally even if we were to fix this particular mismatch with a different nesting for the merge case, we're still slotting in a block that has a owner of the reloc root objectid into a normal tree, so that block will have its lockdep key set to the tree reloc root, and create a lockdep splat later on when we wander into that block from the fs root. Unfortunately the only solution here is to make sure we do not set the lockdep key to the reloc tree lockdep key normally, and then reset any blocks we wander into from the reloc root when we're doing the merged. This solves the problem of having mixed tree reloc keys intermixed with normal tree keys, and then allows us to make sure in the merge case we maintain the lock order of normal tree -> reloc tree We handle this by setting a bit on the reloc root when we do the search for the block we want to relocate, and any block we search into or COW at that point gets set to the reloc tree key. This works correctly because we only ever COW down to the parent node, so we aren't resetting the key for the block we're linking into the fs root. With this patch we no longer have the lockdep splat in btrfs/187. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: fix repair of compressed extentsChristoph Hellwig
Currently the checksum of compressed extents is verified based on the compressed data and the lower btrfs_bio, but the actual repair process is driven by end_bio_extent_readpage on the upper btrfs_bio for the decompressed data. This has a bunch of issues, including not being able to properly communicate the failed mirror up in case that the I/O submission got preempted, a general loss of if an error was an I/O error or a checksum verification failure, but most importantly that this design causes btrfs_clean_io_failure to eventually write back the uncompressed good data onto the disk sectors that are supposed to contain compressed data. Fix this by moving the repair to the lower btrfs_bio. To do so, a fair amount of code has to be reshuffled: a) the lower btrfs_bio now needs a valid csum pointer. The easiest way to achieve that is to pass NULL btrfs_lookup_bio_sums and just use the btrfs_bio management of csums. For a compressed_bio that is split into multiple btrfs_bios this means additional memory allocations, but the code becomes a lot more regular. b) checksum verification now runs directly on the lower btrfs_bio instead of the compressed_bio. This actually nicely simplifies the end I/O processing. c) btrfs_repair_one_sector can't just look up the logical address for the file offset any more, as there is no corresponding relative offsets that apply to the file offset and the logic address for compressed extents. Instead require that the saved bvec_iter in the btrfs_bio is filled out for all read bios and use that, which again removes a fair amount of code. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: remove the start argument to check_data_csum and exportChristoph Hellwig
Derive the value of start from the btrfs_bio now that ->file_offset is always valid. Also export and rename the function so it's available outside of inode.c as we'll need that soon. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: zoned: wait until zone is finished when allocation didn't progressNaohiro Aota
When the allocated position doesn't progress, we cannot submit IOs to finish a block group, but there should be ongoing IOs that will finish a block group. So, in that case, we wait for a zone to be finished and retry the allocation after that. Introduce a new flag BTRFS_FS_NEED_ZONE_FINISH for fs_info->flags to indicate we need a zone finish to have proceeded. The flag is set when the allocator detected it cannot activate a new block group. And, it is cleared once a zone is finished. CC: stable@vger.kernel.org # 5.16+ Fixes: afba2bc036b0 ("btrfs: zoned: implement active zone tracking") Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: convert count_max_extents() to use fs_info->max_extent_sizeNaohiro Aota
If count_max_extents() uses BTRFS_MAX_EXTENT_SIZE to calculate the number of extents needed, btrfs release the metadata reservation too much on its way to write out the data. Now that BTRFS_MAX_EXTENT_SIZE is replaced with fs_info->max_extent_size, convert count_max_extents() to use it instead, and fix the calculation of the metadata reservation. CC: stable@vger.kernel.org # 5.12+ Fixes: d8e3fb106f39 ("btrfs: zoned: use ZONE_APPEND write for zoned mode") Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: replace BTRFS_MAX_EXTENT_SIZE with fs_info->max_extent_sizeNaohiro Aota
On zoned filesystem, data write out is limited by max_zone_append_size, and a large ordered extent is split according the size of a bio. OTOH, the number of extents to be written is calculated using BTRFS_MAX_EXTENT_SIZE, and that estimated number is used to reserve the metadata bytes to update and/or create the metadata items. The metadata reservation is done at e.g, btrfs_buffered_write() and then released according to the estimation changes. Thus, if the number of extent increases massively, the reserved metadata can run out. The increase of the number of extents easily occurs on zoned filesystem if BTRFS_MAX_EXTENT_SIZE > max_zone_append_size. And, it causes the following warning on a small RAM environment with disabling metadata over-commit (in the following patch). [75721.498492] ------------[ cut here ]------------ [75721.505624] BTRFS: block rsv 1 returned -28 [75721.512230] WARNING: CPU: 24 PID: 2327559 at fs/btrfs/block-rsv.c:537 btrfs_use_block_rsv+0x560/0x760 [btrfs] [75721.581854] CPU: 24 PID: 2327559 Comm: kworker/u64:10 Kdump: loaded Tainted: G W 5.18.0-rc2-BTRFS-ZNS+ #109 [75721.597200] Hardware name: Supermicro Super Server/H12SSL-NT, BIOS 2.0 02/22/2021 [75721.607310] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs] [75721.616209] RIP: 0010:btrfs_use_block_rsv+0x560/0x760 [btrfs] [75721.646649] RSP: 0018:ffffc9000fbdf3e0 EFLAGS: 00010286 [75721.654126] RAX: 0000000000000000 RBX: 0000000000004000 RCX: 0000000000000000 [75721.663524] RDX: 0000000000000004 RSI: 0000000000000008 RDI: fffff52001f7be6e [75721.672921] RBP: ffffc9000fbdf420 R08: 0000000000000001 R09: ffff889f8d1fc6c7 [75721.682493] R10: ffffed13f1a3f8d8 R11: 0000000000000001 R12: ffff88980a3c0e28 [75721.692284] R13: ffff889b66590000 R14: ffff88980a3c0e40 R15: ffff88980a3c0e8a [75721.701878] FS: 0000000000000000(0000) GS:ffff889f8d000000(0000) knlGS:0000000000000000 [75721.712601] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [75721.720726] CR2: 000055d12e05c018 CR3: 0000800193594000 CR4: 0000000000350ee0 [75721.730499] Call Trace: [75721.735166] <TASK> [75721.739886] btrfs_alloc_tree_block+0x1e1/0x1100 [btrfs] [75721.747545] ? btrfs_alloc_logged_file_extent+0x550/0x550 [btrfs] [75721.756145] ? btrfs_get_32+0xea/0x2d0 [btrfs] [75721.762852] ? btrfs_get_32+0xea/0x2d0 [btrfs] [75721.769520] ? push_leaf_left+0x420/0x620 [btrfs] [75721.776431] ? memcpy+0x4e/0x60 [75721.781931] split_leaf+0x433/0x12d0 [btrfs] [75721.788392] ? btrfs_get_token_32+0x580/0x580 [btrfs] [75721.795636] ? push_for_double_split.isra.0+0x420/0x420 [btrfs] [75721.803759] ? leaf_space_used+0x15d/0x1a0 [btrfs] [75721.811156] btrfs_search_slot+0x1bc3/0x2790 [btrfs] [75721.818300] ? lock_downgrade+0x7c0/0x7c0 [75721.824411] ? free_extent_buffer.part.0+0x107/0x200 [btrfs] [75721.832456] ? split_leaf+0x12d0/0x12d0 [btrfs] [75721.839149] ? free_extent_buffer.part.0+0x14f/0x200 [btrfs] [75721.846945] ? free_extent_buffer+0x13/0x20 [btrfs] [75721.853960] ? btrfs_release_path+0x4b/0x190 [btrfs] [75721.861429] btrfs_csum_file_blocks+0x85c/0x1500 [btrfs] [75721.869313] ? rcu_read_lock_sched_held+0x16/0x80 [75721.876085] ? lock_release+0x552/0xf80 [75721.881957] ? btrfs_del_csums+0x8c0/0x8c0 [btrfs] [75721.888886] ? __kasan_check_write+0x14/0x20 [75721.895152] ? do_raw_read_unlock+0x44/0x80 [75721.901323] ? _raw_write_lock_irq+0x60/0x80 [75721.907983] ? btrfs_global_root+0xb9/0xe0 [btrfs] [75721.915166] ? btrfs_csum_root+0x12b/0x180 [btrfs] [75721.921918] ? btrfs_get_global_root+0x820/0x820 [btrfs] [75721.929166] ? _raw_write_unlock+0x23/0x40 [75721.935116] ? unpin_extent_cache+0x1e3/0x390 [btrfs] [75721.942041] btrfs_finish_ordered_io.isra.0+0xa0c/0x1dc0 [btrfs] [75721.949906] ? try_to_wake_up+0x30/0x14a0 [75721.955700] ? btrfs_unlink_subvol+0xda0/0xda0 [btrfs] [75721.962661] ? rcu_read_lock_sched_held+0x16/0x80 [75721.969111] ? lock_acquire+0x41b/0x4c0 [75721.974982] finish_ordered_fn+0x15/0x20 [btrfs] [75721.981639] btrfs_work_helper+0x1af/0xa80 [btrfs] [75721.988184] ? _raw_spin_unlock_irq+0x28/0x50 [75721.994643] process_one_work+0x815/0x1460 [75722.000444] ? pwq_dec_nr_in_flight+0x250/0x250 [75722.006643] ? do_raw_spin_trylock+0xbb/0x190 [75722.013086] worker_thread+0x59a/0xeb0 [75722.018511] kthread+0x2ac/0x360 [75722.023428] ? process_one_work+0x1460/0x1460 [75722.029431] ? kthread_complete_and_exit+0x30/0x30 [75722.036044] ret_from_fork+0x22/0x30 [75722.041255] </TASK> [75722.045047] irq event stamp: 0 [75722.049703] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [75722.057610] hardirqs last disabled at (0): [<ffffffff8118a94a>] copy_process+0x1c1a/0x66b0 [75722.067533] softirqs last enabled at (0): [<ffffffff8118a989>] copy_process+0x1c59/0x66b0 [75722.077423] softirqs last disabled at (0): [<0000000000000000>] 0x0 [75722.085335] ---[ end trace 0000000000000000 ]--- To fix the estimation, we need to introduce fs_info->max_extent_size to replace BTRFS_MAX_EXTENT_SIZE, which allow setting the different size for regular vs zoned filesystem. Set fs_info->max_extent_size to BTRFS_MAX_EXTENT_SIZE by default. On zoned filesystem, it is set to fs_info->max_zone_append_size. CC: stable@vger.kernel.org # 5.12+ Fixes: d8e3fb106f39 ("btrfs: zoned: use ZONE_APPEND write for zoned mode") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: zoned: revive max_zone_append_bytesNaohiro Aota
This patch is basically a revert of commit 5a80d1c6a270 ("btrfs: zoned: remove max_zone_append_size logic"), but without unnecessary ASSERT and check. The max_zone_append_size will be used as a hint to estimate the number of extents to cover delalloc/writeback region in the later commits. The size of a ZONE APPEND bio is also limited by queue_max_segments(), so this commit considers it to calculate max_zone_append_size. Technically, a bio can be larger than queue_max_segments() * PAGE_SIZE if the pages are contiguous. But, it is safe to consider "queue_max_segments() * PAGE_SIZE" as an upper limit of an extent size to calculate the number of extents needed to write data. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: collect commit stats, count, durationIoannis Angelakopoulos
Track several stats about transaction commit, to be later exported via sysfs: - number of commits so far - duration of the last commit in ns - maximum commit duration seen so far in ns - total duration for all commits so far in ns The update of the commit stats occurs after the commit thread has gone through all the logic that checks if there is another thread committing at the same time. This means that we only account for actual commit work in the commit stats we report and not the time the thread spends waiting until it is ready to do the commit work. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Ioannis Angelakopoulos <iangelak@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: use named constant for reserved device spaceQu Wenruo
There's a reserved space on each device of size 1MiB that can be used by bootloaders or to avoid accidental overwrite. Use a symbolic constant with the explaining comment instead of hard coding the value and multiple comments. Note: since btrfs-progs v4.1, mkfs.btrfs will reserve the first 1MiB for the primary super block (at offset 64KiB), until then the range could have been used by mistake. Kernel has been always respecting the 1MiB range for writes. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: pass bits by value not by pointer for extent_state helpersDavid Sterba
The bits are passed to all extent state helpers for no apparent reason, the value only read and never updated so remove the indirection and pass it directly. Also unify the type to u32 where needed. Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: make btrfs_super_block::log_root_transid deprecatedQu Wenruo
When using "btrfs inspect-internal dump-super" to inspect an fs with dirty log, it always shows the log_root_transid as 0: log_root 30474240 log_root_transid 0 <<< log_root_level 0 It turns out that, btrfs_super_block::log_root_transid is never really utilized (even no read for it). This can date back to the introduction of btrfs into upstream kernel. In fact, when reading log tree root, we always use btrfs_super_block::generation + 1 as the expected generation. So here we're completely safe to mark this member deprecated. In theory we can easily reuse this member for other purposes, but to be extra safe, here we follow the leafsize way, by adding "__unused_" for log_root_transid. And we can safely remove the accessors, since there is no such callers from the very beginning. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: remove btrfs_end_io_wqChristoph Hellwig
All reads bio that go through btrfs_map_bio need to be completed in user context. And read I/Os are the most common and timing critical in almost any file system workloads. Embed a work_struct into struct btrfs_bio and use it to complete all read bios submitted through btrfs_map, using the REQ_META flag to decide which workqueue they are placed on. This removes the need for a separate 128 byte allocation (typically rounded up to 192 bytes by slab) for all reads with a size increase of 24 bytes for struct btrfs_bio. Future patches will reorganize struct btrfs_bio to make use of this extra space for writes as well. (All sizes are based a on typical 64-bit non-debug build) Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: don't use btrfs_bio_wq_end_io for compressed writesChristoph Hellwig
Compressed write bio completion is the only user of btrfs_bio_wq_end_io for writes, and the use of btrfs_bio_wq_end_io is a little suboptimal here as we only real need user context for the final completion of a compressed_bio structure, and not every single bio completion. Add a work_struct to struct compressed_bio instead and use that to call finish_compressed_bio_write. This allows to remove all handling of write bios in the btrfs_bio_wq_end_io infrastructure. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: defer I/O completion based on the btrfs_raid_bioChristoph Hellwig
Instead of attaching an extra allocation an indirect call to each low-level bio issued by the RAID code, add a work_struct to struct btrfs_raid_bio and only defer the per-rbio completion action. The per-bio action for all the I/Os are trivial and can be safely done from interrupt context. As a nice side effect this also allows sharing the boilerplate code for the per-bio completions Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: split btrfs_submit_data_bio to read and write partsChristoph Hellwig
Split btrfs_submit_data_bio into one helper for reads and one for writes. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: send: send compressed extents with encoded writesOmar Sandoval
Now that all of the pieces are in place, we can use the ENCODED_WRITE command to send compressed extents when appropriate. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: factor out a btrfs_csum_ptr helperChristoph Hellwig
Add a helper to find the csum for a byte offset into the csum buffer. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: introduce a data checksum checking helperQu Wenruo
Although we have several data csum verification code, we never have a function really just to verify checksum for one sector. Function check_data_csum() do extra work for error reporting, thus it requires a lot of extra things like file offset, bio_offset etc. Function btrfs_verify_data_csum() is even worse, it will utilize page checked flag, which means it can not be utilized for direct IO pages. Here we introduce a new helper, btrfs_check_sector_csum(), which really only accept a sector in page, and expected checksum pointer. We use this function to implement check_data_csum(), and export it for incoming patch. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> [hch: keep passing the csum array as an arguments, as the callers want to print it, rename per request] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: fix typos in commentsDavid Sterba
Codespell has found a few typos. Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-15Revert "btrfs: turn delayed_nodes_tree into an XArray"David Sterba
This reverts commit 253bf57555e451dec5a7f09dc95d380ce8b10e5b. Revert the xarray conversion, there's a problem with potential sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS allocation. The radix tree used the preloading mechanism to avoid sleeping but this is not available in xarray. Conversion from spin lock to mutex is possible but at time of rc6 is riskier than a clean revert. [1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/ Reported-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-15Revert "btrfs: turn fs_info member buffer_radix into XArray"David Sterba
This reverts commit 8ee922689d67b7cfa6acbe2aa1ee76ac72e6fc8a. Revert the xarray conversion, there's a problem with potential sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS allocation. The radix tree used the preloading mechanism to avoid sleeping but this is not available in xarray. Conversion from spin lock to mutex is possible but at time of rc6 is riskier than a clean revert. [1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/ Reported-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-15Revert "btrfs: turn fs_roots_radix in btrfs_fs_info into an XArray"David Sterba
This reverts commit 48b36a602a335c184505346b5b37077840660634. Revert the xarray conversion, there's a problem with potential sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS allocation. The radix tree used the preloading mechanism to avoid sleeping but this is not available in xarray. Conversion from spin lock to mutex is possible but at time of rc6 is riskier than a clean revert. [1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/ Reported-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-06-21btrfs: add missing inode updates on each iteration when replacing extentsFilipe Manana
When replacing file extents, called during fallocate, hole punching, clone and deduplication, we may not be able to replace/drop all the target file extent items with a single transaction handle. We may get -ENOSPC while doing it, in which case we release the transaction handle, balance the dirty pages of the btree inode, flush delayed items and get a new transaction handle to operate on what's left of the target range. By dropping and replacing file extent items we have effectively modified the inode, so we should bump its iversion and update its mtime/ctime before we update the inode item. This is because if the transaction we used for partially modifying the inode gets committed by someone after we release it and before we finish the rest of the range, a power failure happens, then after mounting the filesystem our inode has an outdated iversion and mtime/ctime, corresponding to the values it had before we changed it. So add the missing iversion and mtime/ctime updates. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: move struct btrfs_dio_private to inode.cChristoph Hellwig
The btrfs_dio_private structure is only used in inode.c, so move the definition there. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: add a btrfs_dio_rw wrapperChristoph Hellwig
Add a wrapper around iomap_dio_rw that keeps the direct I/O internals isolated in inode.c. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: rename bio_flags in parameters and switch typeDavid Sterba
Several functions take parameter bio_flags that was simplified to just compress type, unify it and change the type accordingly. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: sink parameter is_data to btrfs_set_disk_extent_flagsDavid Sterba
The parameter has been added in 2009 in the infamous monster commit 5d4f98a28c7d ("Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE)") but not used ever since. We can sink it and allow further simplifications. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: turn fs_roots_radix in btrfs_fs_info into an XArrayGabriel Niebler
… rename it to simply fs_roots and adjust all usages of this object to use the XArray API, because it is notionally easier to use and understand, as it provides array semantics, and also takes care of locking for us, further simplifying the code. Also do some refactoring, esp. where the API change requires largely rewriting some functions, anyway. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Gabriel Niebler <gniebler@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: turn fs_info member buffer_radix into XArrayGabriel Niebler
… named 'extent_buffers'. Also adjust all usages of this object to use the XArray API, which greatly simplifies the code as it takes care of locking and is generally easier to use and understand, providing notionally simpler array semantics. Also perform some light refactoring. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Gabriel Niebler <gniebler@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: turn delayed_nodes_tree into an XArrayGabriel Niebler
… in the btrfs_root struct and adjust all usages of this object to use the XArray API, because it is notionally easier to use and understand, as it provides array semantics, and also takes care of locking for us, further simplifying the code. Also use the opportunity to do some light refactoring. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Gabriel Niebler <gniebler@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: use a normal workqueue for rmw_workersChristoph Hellwig
rmw_workers doesn't need ordered execution or thread disabling threshold (as the thresh parameter is less than DFT_THRESHOLD). Just switch to the normal workqueues that use a lot less resources, especially in the work_struct vs btrfs_work structures. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: use normal workqueues for scrubChristoph Hellwig
All three scrub workqueues don't need ordered execution or thread disabling threshold (as the thresh parameter is less than DFT_THRESHOLD). Just switch to the normal workqueues that use a lot less resources, especially in the work_struct vs btrfs_work structures. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: simplify WQ_HIGHPRI handling in struct btrfs_workqueueChristoph Hellwig
Just let the one caller that wants optional WQ_HIGHPRI handling allocate a separate btrfs_workqueue for that. This allows to rename struct __btrfs_workqueue to btrfs_workqueue, remove a pointer indirection and separate allocation for all btrfs_workqueue users and generally simplify the code. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: do not return errors from submit_bio_hook_t instancesChristoph Hellwig
Both btrfs_repair_one_sector and submit_bio_one as the direct caller of one of the instances ignore errors as they expect the methods themselves to call ->bi_end_io on error. Remove the unused and dangerous return value. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: move btrfs_readpage to extent_io.cChristoph Hellwig
Keep btrfs_readpage next to btrfs_do_readpage and the other address space operations. This allows to keep submit_one_bio and struct btrfs_bio_ctrl file local in extent_io.c. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: use a read/write lock for protecting the block groups treeFilipe Manana
Currently we use a spin lock to protect the red black tree that we use to track block groups. Most accesses to that tree are actually read only and for large filesystems, with thousands of block groups, it actually has a bad impact on performance, as concurrent read only searches on the tree are serialized. Read only searches on the tree are very frequent and done when: 1) Pinning and unpinning extents, as we need to lookup the respective block group from the tree; 2) Freeing the last reference of a tree block, regardless if we pin the underlying extent or add it back to free space cache/tree; 3) During NOCOW writes, both buffered IO and direct IO, we need to check if the block group that contains an extent is read only or not and to increment the number of NOCOW writers in the block group. For those operations we need to search for the block group in the tree. Similarly, after creating the ordered extent for the NOCOW write, we need to decrement the number of NOCOW writers from the same block group, which requires searching for it in the tree; 4) Decreasing the number of extent reservations in a block group; 5) When allocating extents and freeing reserved extents; 6) Adding and removing free space to the free space tree; 7) When releasing delalloc bytes during ordered extent completion; 8) When relocating a block group; 9) During fitrim, to iterate over the block groups; 10) etc; Write accesses to the tree, to add or remove block groups, are much less frequent as they happen only when allocating a new block group or when deleting a block group. We also use the same spin lock to protect the list of currently caching block groups. Additions to this list are made when we need to cache a block group, because we don't have a free space cache for it (or we have but it's invalid), and removals from this list are done when caching of the block group's free space finishes. These cases are also not very common, but when they happen, they happen only once when the filesystem is mounted. So switch the lock that protects the tree of block groups from a spinning lock to a read/write lock. Reviewed-by: Nikolay Borisov <nborisov@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>
2022-05-16btrfs: use rbtree with leftmost node cached for tracking lowest block groupFilipe Manana
We keep track of the start offset of the block group with the lowest start offset at fs_info->first_logical_byte. This requires explicitly updating that field every time we add, delete or lookup a block group to/from the red black tree at fs_info->block_group_cache_tree. Since the block group with the lowest start address happens to always be the one that is the leftmost node of the tree, we can use a red black tree that caches the left most node. Then when we need the start address of that block group, we can just quickly get the leftmost node in the tree and extract the start offset of that node's block group. This avoids the need to explicitly keep track of that address in the dedicated member fs_info->first_logical_byte, and it also allows the next patch in the series to switch the lock that protects the red black tree from a spin lock to a read/write lock - without this change it would be tricky because block group searches also update fs_info->first_logical_byte. Reviewed-by: Nikolay Borisov <nborisov@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>
2022-05-16btrfs: remove the zoned/zone_size union in struct btrfs_fs_infoChristoph Hellwig
Reading a value from a different member of a union is not just a great way to obfuscate code, but also creates an aliasing violation. Switch btrfs_is_zoned to look at ->zone_size and remove the union. Note: union was to simplify the detection of zoned filesystem but now this is wrapped behind btrfs_is_zoned so we can drop the union. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> [ add note ] Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: avoid blocking on space revervation when doing nowait dio writesFilipe Manana
When doing a NOWAIT direct IO write, if we can NOCOW then it means we can proceed with the non-blocking, NOWAIT path. However reserving the metadata space and qgroup meta space can often result in blocking - flushing delalloc, wait for ordered extents to complete, trigger transaction commits, etc, going against the semantics of a NOWAIT write. So make the NOWAIT write path to try to reserve all the metadata it needs without resulting in a blocking behaviour - if we get -ENOSPC or -EDQUOT then return -EAGAIN to make the caller fallback to a blocking direct IO write. This is part of a patchset comprised of the following patches: btrfs: avoid blocking on page locks with nowait dio on compressed range btrfs: avoid blocking nowait dio when locking file range btrfs: avoid double nocow check when doing nowait dio writes btrfs: stop allocating a path when checking if cross reference exists btrfs: free path at can_nocow_extent() before checking for checksum items btrfs: release path earlier at can_nocow_extent() btrfs: avoid blocking when allocating context for nowait dio read/write btrfs: avoid blocking on space revervation when doing nowait dio writes The following test was run before and after applying this patchset: $ cat io-uring-nodatacow-test.sh #!/bin/bash DEV=/dev/sdc MNT=/mnt/sdc MOUNT_OPTIONS="-o ssd -o nodatacow" MKFS_OPTIONS="-R free-space-tree -O no-holes" NUM_JOBS=4 FILE_SIZE=8G RUN_TIME=300 cat <<EOF > /tmp/fio-job.ini [io_uring_rw] rw=randrw fsync=0 fallocate=posix group_reporting=1 direct=1 ioengine=io_uring iodepth=64 bssplit=4k/20:8k/20:16k/20:32k/10:64k/10:128k/5:256k/5:512k/5:1m/5 filesize=$FILE_SIZE runtime=$RUN_TIME time_based filename=foobar directory=$MNT numjobs=$NUM_JOBS thread EOF echo performance | \ tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor umount $MNT &> /dev/null mkfs.btrfs -f $MKFS_OPTIONS $DEV &> /dev/null mount $MOUNT_OPTIONS $DEV $MNT fio /tmp/fio-job.ini umount $MNT The test was run a 12 cores box with 64G of ram, using a non-debug kernel config (Debian's default config) and a spinning disk. Result before the patchset: READ: bw=407MiB/s (427MB/s), 407MiB/s-407MiB/s (427MB/s-427MB/s), io=119GiB (128GB), run=300175-300175msec WRITE: bw=407MiB/s (427MB/s), 407MiB/s-407MiB/s (427MB/s-427MB/s), io=119GiB (128GB), run=300175-300175msec Result after the patchset: READ: bw=436MiB/s (457MB/s), 436MiB/s-436MiB/s (457MB/s-457MB/s), io=128GiB (137GB), run=300044-300044msec WRITE: bw=435MiB/s (456MB/s), 435MiB/s-435MiB/s (456MB/s-456MB/s), io=128GiB (137GB), run=300044-300044msec That's about +7.2% throughput for reads and +6.9% for writes. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: stop allocating a path when checking if cross reference existsFilipe Manana
At btrfs_cross_ref_exist() we always allocate a path, but we really don't need to because all its callers (only 2) already have an allocated path that is not being used when they call btrfs_cross_ref_exist(). So change btrfs_cross_ref_exist() to take a path as an argument and update both its callers to pass in the unused path they have when they call btrfs_cross_ref_exist(). Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: add messages to printk indexJonathan Lassoff
In order for end users to quickly react to new issues that come up in production, it is proving useful to leverage this printk indexing system. This printk index enables kernel developers to use calls to printk() with changeable ad-hoc format strings, while still enabling end users to detect changes and develop a semi-stable interface for detecting and parsing these messages. So that detailed Btrfs messages are captured by this printk index, this patch wraps btrfs_printk and btrfs_handle_fs_error with macros. Example of the generated list: https://lore.kernel.org/lkml/12588e13d51a9c3bf59467d3fc1ac2162f1275c1.1647539056.git.jof@thejof.com Signed-off-by: Jonathan Lassoff <jof@thejof.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: add and use helper to assert an inode range is cleanFilipe Manana
We have four different scenarios where we don't expect to find ordered extents after locking a file range: 1) During plain fallocate; 2) During hole punching; 3) During zero range; 4) During reflinks (both cloning and deduplication). This is because in all these cases we follow the pattern: 1) Lock the inode's VFS lock in exclusive mode; 2) Lock the inode's i_mmap_lock in exclusive node, to serialize with mmap writes; 3) Flush delalloc in a file range and wait for all ordered extents to complete - both done through btrfs_wait_ordered_range(); 4) Lock the file range in the inode's io_tree. So add a helper that asserts that we don't have ordered extents for a given range. Make the four scenarios listed above use this helper after locking the respective file range. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: move common inode creation code into btrfs_create_new_inode()Omar Sandoval
All of our inode creation code paths duplicate the calls to btrfs_init_inode_security() and btrfs_add_link(). Subvolume creation additionally duplicates property inheritance and the call to btrfs_set_inode_index(). Fix this by moving the common code into btrfs_create_new_inode(). This accomplishes a few things at once: 1. It reduces code duplication. 2. It allows us to set up the inode completely before inserting the inode item, removing calls to btrfs_update_inode(). 3. It fixes a leak of an inode on disk in some error cases. For example, in btrfs_create(), if btrfs_new_inode() succeeds, then we have inserted an inode item and its inode ref. However, if something after that fails (e.g., btrfs_init_inode_security()), then we end the transaction and then decrement the link count on the inode. If the transaction is committed and the system crashes before the failed inode is deleted, then we leak that inode on disk. Instead, this refactoring aborts the transaction when we can't recover more gracefully. 4. It exposes various ways that subvolume creation diverges from mkdir in terms of inheriting flags, properties, permissions, and POSIX ACLs, a lot of which appears to be accidental. This patch explicitly does _not_ change the existing non-standard behavior, but it makes those differences more clear in the code and documents them so that we can discuss whether they should be changed. Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: reserve correct number of items for inode creationOmar Sandoval
The various inode creation code paths do not account for the compression property, POSIX ACLs, or the parent inode item when starting a transaction. Fix it by refactoring all of these code paths to use a new function, btrfs_new_inode_prepare(), which computes the correct number of items. To do so, it needs to know whether POSIX ACLs will be created, so move the ACL creation into that function. To reduce the number of arguments that need to be passed around for inode creation, define struct btrfs_new_inode_args containing all of the relevant information. btrfs_new_inode_prepare() will also be a good place to set up the fscrypt context and encrypted filename in the future. Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: allocate inode outside of btrfs_new_inode()Omar Sandoval
Instead of calling new_inode() and inode_init_owner() inside of btrfs_new_inode(), do it in the callers. This allows us to pass in just the inode instead of the mnt_userns and mode and removes the need for memalloc_nofs_{save,restores}() since we do it before starting a transaction. In create_subvol(), it also means we no longer have to look up the inode again to instantiate it. This also paves the way for some more cleanups in later patches. This also removes the comments about Smack checking i_op, which are no longer true since commit 5d6c31910bc0 ("xattr: Add __vfs_{get,set,remove}xattr helpers"). Now it checks inode->i_opflags & IOP_XATTR, which is set based on sb->s_xattr. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16btrfs: introduce btrfs_for_each_slot iterator macroGabriel Niebler
There is a common pattern when searching for a key in btrfs: * Call btrfs_search_slot to find the slot for the key * Enter an endless loop: * If the found slot is larger than the no. of items in the current leaf, check the next leaf * If it's still not found in the next leaf, terminate the loop * Otherwise do something with the found key * Increment the current slot and continue To reduce code duplication, we can replace this code pattern with an iterator macro, similar to the existing for_each_X macros found elsewhere in the kernel. This also makes the code easier to understand for newcomers by putting a name to the encapsulated functionality. Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Signed-off-by: Gabriel Niebler <gniebler@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>