summaryrefslogtreecommitdiff
path: root/fs/btrfs
AgeCommit message (Collapse)Author
2021-02-08btrfs: do not warn if we can't find the reloc root when looking up backrefJosef Bacik
The backref code is looking for a reloc_root that corresponds to the given fs root. However any number of things could have gone wrong while initializing that reloc_root, like ENOMEM while trying to allocate the root itself, or EIO while trying to write the root item. This would result in no corresponding reloc_root being in the reloc root cache, and thus would return NULL when we do the find_reloc_root() call. Because of this we do not want to WARN_ON(). This presumably was meant to catch developer errors, cases where we messed up adding the reloc root. However we can easily hit this case with error injection, and thus should not do a WARN_ON(). CC: stable@vger.kernel.org # 5.10+ Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: splice remaining dirty_bg's onto the transaction dirty bg listJosef Bacik
While doing error injection testing with my relocation patches I hit the following assert: assertion failed: list_empty(&block_group->dirty_list), in fs/btrfs/block-group.c:3356 ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.h:3357! invalid opcode: 0000 [#1] SMP NOPTI CPU: 0 PID: 24351 Comm: umount Tainted: G W 5.10.0-rc3+ #193 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 RIP: 0010:assertfail.constprop.0+0x18/0x1a RSP: 0018:ffffa09b019c7e00 EFLAGS: 00010282 RAX: 0000000000000056 RBX: ffff8f6492c18000 RCX: 0000000000000000 RDX: ffff8f64fbc27c60 RSI: ffff8f64fbc19050 RDI: ffff8f64fbc19050 RBP: ffff8f6483bbdc00 R08: 0000000000000000 R09: 0000000000000000 R10: ffffa09b019c7c38 R11: ffffffff85d70928 R12: ffff8f6492c18100 R13: ffff8f6492c18148 R14: ffff8f6483bbdd70 R15: dead000000000100 FS: 00007fbfda4cdc40(0000) GS:ffff8f64fbc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbfda666fd0 CR3: 000000013cf66002 CR4: 0000000000370ef0 Call Trace: btrfs_free_block_groups.cold+0x55/0x55 close_ctree+0x2c5/0x306 ? fsnotify_destroy_marks+0x14/0x100 generic_shutdown_super+0x6c/0x100 kill_anon_super+0x14/0x30 btrfs_kill_super+0x12/0x20 deactivate_locked_super+0x36/0xa0 cleanup_mnt+0x12d/0x190 task_work_run+0x5c/0xa0 exit_to_user_mode_prepare+0x1b1/0x1d0 syscall_exit_to_user_mode+0x54/0x280 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This happened because I injected an error in btrfs_cow_block() while running the dirty block groups. When we run the dirty block groups, we splice the list onto a local list to process. However if an error occurs, we only cleanup the transactions dirty block group list, not any pending block groups we have on our locally spliced list. In fact if we fail to allocate a path in this function we'll also fail to clean up the splice list. Fix this by splicing the list back onto the transaction dirty block group list so that the block groups are cleaned up. Then add a 'out' label and have the error conditions jump to out so that the errors are handled properly. This also has the side-effect of fixing a problem where we would clear 'ret' on error because we unconditionally ran btrfs_run_delayed_refs(). CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix reloc root leak with 0 ref reloc roots on recoveryJosef Bacik
When recovering a relocation, if we run into a reloc root that has 0 refs we simply add it to the reloc_control->reloc_roots list, and then clean it up later. The problem with this is __del_reloc_root() doesn't do anything if the root isn't in the radix tree, which in this case it won't be because we never call __add_reloc_root() on the reloc_root. This exit condition simply isn't correct really. During normal operation we can remove ourselves from the rb tree and then we're meant to clean up later at merge_reloc_roots() time, and this happens correctly. During recovery we're depending on free_reloc_roots() to drop our references, but we're short-circuiting. Fix this by continuing to check if we're on the list and dropping ourselves from the reloc_control root list and dropping our reference appropriately. Change the corresponding BUG_ON() to an ASSERT() that does the correct thing if we aren't in the rb tree. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: remove repeated word in struct member commentNigel Christian
Comment for processed extent end of range has an unnecessary "in", remove it. Signed-off-by: Nigel Christian <nigel.l.christian@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: account for new extents being deleted in total_bytes_pinnedJosef Bacik
My recent patch set "A variety of lock contention fixes", found here https://lore.kernel.org/linux-btrfs/cover.1608319304.git.josef@toxicpanda.com/ (Tracked in https://github.com/btrfs/linux/issues/86) that reduce lock contention on the extent root by running delayed refs less often resulted in a regression in generic/371. This test fallocate()'s the fs until it's full, deletes all the files, and then tries to fallocate() until full again. Before these patches we would run all of the delayed refs during flushing, and then would commit the transaction because we had plenty of pinned space to recover in order to allocate. However my patches made it so we weren't running the delayed refs as aggressively, which meant that we appeared to have less pinned space when we were deciding to commit the transaction. We use the space_info->total_bytes_pinned to approximate how much space we have pinned. It's approximate because if we remove a reference to an extent we may free it, but there may be more references to it than we know of at that point, but we account it as pinned at the creation time, and then it's properly accounted when the delayed ref runs. The way we account for pinned space is if the delayed_ref_head->total_ref_mod is < 0, because that is clearly a freeing option. However there is another case, and that is where ->total_ref_mod == 0 && ->must_insert_reserved == 1. When we allocate a new extent, we have ->total_ref_mod == 1 and we have ->must_insert_reserved == 1. This is used to indicate that it is a brand new extent and will need to have its extent entry added before we modify any references on the delayed ref head. But if we subsequently remove that extent reference, our ->total_ref_mod will be 0, and that space will be pinned and freed. Accounting for this case properly allows for generic/371 to pass with my delayed refs patches applied. It's important to note that this problem exists without the referenced patches, it just was uncovered by them. 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>
2021-02-08btrfs: handle space_info::total_bytes_pinned inside the delayed ref itselfJosef Bacik
Currently we pass things around to figure out if we maybe freeing data based on the state of the delayed refs head. This makes the accounting sort of confusing and hard to follow, as it's distinctly separate from the delayed ref heads stuff, but also depends on it entirely. Fix this by explicitly adjusting the space_info->total_bytes_pinned in the delayed refs code. We now have two places where we modify this counter, once where we create the delayed and destroy the delayed refs, and once when we pin and unpin the extents. This means there is a slight overlap between delayed refs and the pin/unpin mechanisms, but this is simply used by the ENOSPC infrastructure to determine if we need to commit the transaction, so there's no adverse affect from this, we might simply commit thinking it will give us enough space when it might not. 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>
2021-02-08btrfs: enable W=1 checks for btrfsNikolay Borisov
Now that the btrfs' codebase is clean of almost all W=1 warnings let's enable those checks unconditionally for the entire fs/btrfs/ and its subdirectories to catch potential errors during development. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add some comments ] Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: zoned: remove unused variable in btrfs_sb_log_location_bdevNikolay Borisov
This fixes warning: fs/btrfs/zoned.c:491:6: warning: variable ‘zone_size’ set but not used [-Wunused-but-set-variable] 491 | u64 zone_size; which got introduced in 12659251ca5d ("btrfs: implement log-structured superblock for ZONED mode"). We'll enable the warning by default and want clean build until the relevant zoned patches land. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix parameter description for functions in extent_io.cNikolay Borisov
This makes the file W=1 clean and fixes the following warnings: fs/btrfs/extent_io.c:414: warning: Function parameter or member 'tree' not described in '__etree_search' fs/btrfs/extent_io.c:414: warning: Function parameter or member 'offset' not described in '__etree_search' fs/btrfs/extent_io.c:414: warning: Function parameter or member 'next_ret' not described in '__etree_search' fs/btrfs/extent_io.c:414: warning: Function parameter or member 'prev_ret' not described in '__etree_search' fs/btrfs/extent_io.c:414: warning: Function parameter or member 'p_ret' not described in '__etree_search' fs/btrfs/extent_io.c:414: warning: Function parameter or member 'parent_ret' not described in '__etree_search' fs/btrfs/extent_io.c:1607: warning: Function parameter or member 'tree' not described in 'find_contiguous_extent_bit' fs/btrfs/extent_io.c:1607: warning: Function parameter or member 'start' not described in 'find_contiguous_extent_bit' fs/btrfs/extent_io.c:1607: warning: Function parameter or member 'start_ret' not described in 'find_contiguous_extent_bit' fs/btrfs/extent_io.c:1607: warning: Function parameter or member 'end_ret' not described in 'find_contiguous_extent_bit' fs/btrfs/extent_io.c:1607: warning: Function parameter or member 'bits' not described in 'find_contiguous_extent_bit' fs/btrfs/extent_io.c:1644: warning: Function parameter or member 'tree' not described in 'find_first_clear_extent_bit' fs/btrfs/extent_io.c:1644: warning: Function parameter or member 'start' not described in 'find_first_clear_extent_bit' fs/btrfs/extent_io.c:1644: warning: Function parameter or member 'start_ret' not described in 'find_first_clear_extent_bit' fs/btrfs/extent_io.c:1644: warning: Function parameter or member 'end_ret' not described in 'find_first_clear_extent_bit' fs/btrfs/extent_io.c:1644: warning: Function parameter or member 'bits' not described in 'find_first_clear_extent_bit' fs/btrfs/extent_io.c:4187: warning: Function parameter or member 'epd' not described in 'extent_write_cache_pages' fs/btrfs/extent_io.c:4187: warning: Excess function parameter 'data' description in 'extent_write_cache_pages' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix parameter description in space-info.cNikolay Borisov
With these fixes space-info.c is clear for W=1 warnings, namely the following ones are fixed: fs/btrfs/space-info.c:575: warning: Function parameter or member 'fs_info' not described in 'may_commit_transaction' fs/btrfs/space-info.c:575: warning: Function parameter or member 'space_info' not described in 'may_commit_transaction' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'fs_info' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'space_info' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'ticket' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'flush' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'fs_info' not described in '__reserve_bytes' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'space_info' not described in '__reserve_bytes' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'orig_bytes' not described in '__reserve_bytes' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'flush' not described in '__reserve_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'root' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'block_rsv' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'orig_bytes' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'flush' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1462: warning: Function parameter or member 'fs_info' not described in 'btrfs_reserve_data_bytes' fs/btrfs/space-info.c:1462: warning: Function parameter or member 'bytes' not described in 'btrfs_reserve_data_bytes' fs/btrfs/space-info.c:1462: warning: Function parameter or member 'flush' not described in 'btrfs_reserve_data_bytes' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix parameter description of ↵Nikolay Borisov
btrfs_inode_rsv_release/btrfs_delalloc_release_space Fixes following warnings: fs/btrfs/delalloc-space.c:205: warning: Function parameter or member 'inode' not described in 'btrfs_inode_rsv_release' fs/btrfs/delalloc-space.c:205: warning: Function parameter or member 'qgroup_free' not described in 'btrfs_inode_rsv_release' fs/btrfs/delalloc-space.c:472: warning: Function parameter or member 'reserved' not described in 'btrfs_delalloc_release_space' fs/btrfs/delalloc-space.c:472: warning: Function parameter or member 'qgroup_free' not described in 'btrfs_delalloc_release_space' fs/btrfs/delalloc-space.c:472: warning: Excess function parameter 'release_bytes' description in 'btrfs_delalloc_release_space' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: document btrfs_check_shared parametersNikolay Borisov
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix description format of fs_info of btrfs_wait_on_delayed_iputsNikolay Borisov
Fixes fs/btrfs/inode.c:3101: warning: Function parameter or member 'fs_info' not described in 'btrfs_wait_on_delayed_iputs' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: document fs_info in btrfs_rmap_blockNikolay Borisov
Fixes fs/btrfs/block-group.c:1570: warning: Function parameter or member 'fs_info' not described in 'btrfs_rmap_block' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: document now parameter of peek_discard_listNikolay Borisov
Fixes fs/btrfs/discard.c:203: warning: Function parameter or member 'now' not described in 'peek_discard_list' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: improve parameter description for __btrfs_write_out_cacheNikolay Borisov
Fixes following W=1 warnings: fs/btrfs/free-space-cache.c:1317: warning: Function parameter or member 'root' not described in '__btrfs_write_out_cache' fs/btrfs/free-space-cache.c:1317: warning: Function parameter or member 'inode' not described in '__btrfs_write_out_cache' fs/btrfs/free-space-cache.c:1317: warning: Function parameter or member 'ctl' not described in '__btrfs_write_out_cache' fs/btrfs/free-space-cache.c:1317: warning: Function parameter or member 'block_group' not described in '__btrfs_write_out_cache' fs/btrfs/free-space-cache.c:1317: warning: Function parameter or member 'io_ctl' not described in '__btrfs_write_out_cache' fs/btrfs/free-space-cache.c:1317: warning: Function parameter or member 'trans' not described in '__btrfs_write_out_cache' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix parameter description in delayed-ref.c functionsNikolay Borisov
This fixes the following warnings: fs/btrfs/delayed-ref.c:80: warning: Function parameter or member 'fs_info' not described in 'btrfs_delayed_refs_rsv_release' fs/btrfs/delayed-ref.c:80: warning: Function parameter or member 'nr' not described in 'btrfs_delayed_refs_rsv_release' fs/btrfs/delayed-ref.c:128: warning: Function parameter or member 'fs_info' not described in 'btrfs_migrate_to_delayed_refs_rsv' fs/btrfs/delayed-ref.c:128: warning: Function parameter or member 'src' not described in 'btrfs_migrate_to_delayed_refs_rsv' fs/btrfs/delayed-ref.c:128: warning: Function parameter or member 'num_bytes' not described in 'btrfs_migrate_to_delayed_refs_rsv' fs/btrfs/delayed-ref.c:174: warning: Function parameter or member 'fs_info' not described in 'btrfs_delayed_refs_rsv_refill' fs/btrfs/delayed-ref.c:174: warning: Function parameter or member 'flush' not described in 'btrfs_delayed_refs_rsv_refill' 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>
2021-02-08btrfs: fix function description formats in file-item.cNikolay Borisov
This fixes following W=1 warnings: fs/btrfs/file-item.c:27: warning: Cannot understand * @inode: the inode we want to update the disk_i_size for on line 27 - I thought it was a doc line fs/btrfs/file-item.c:65: warning: Cannot understand * @inode - the inode we're modifying on line 65 - I thought it was a doc line fs/btrfs/file-item.c:91: warning: Cannot understand * @inode - the inode we're modifying on line 91 - I thought it was a doc line Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix parameter description of btrfs_add_extent_mappingNikolay Borisov
This fixes the following compiler warnings: fs/btrfs/extent_map.c:601: warning: Function parameter or member 'fs_info' not described in 'btrfs_add_extent_mapping' fs/btrfs/extent_map.c:601: warning: Function parameter or member 'em_tree' not described in 'btrfs_add_extent_mapping' fs/btrfs/extent_map.c:601: warning: Function parameter or member 'em_in' not described in 'btrfs_add_extent_mapping' fs/btrfs/extent_map.c:601: warning: Function parameter or member 'start' not described in 'btrfs_add_extent_mapping' fs/btrfs/extent_map.c:601: warning: Function parameter or member 'len' not described in 'btrfs_add_extent_mapping' 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>
2021-02-08btrfs: document modified parameter of add_extent_mappingNikolay Borisov
Fixes fs/btrfs/extent_map.c:399: warning: Function parameter or member 'modified' not described in 'add_extent_mapping' 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>
2021-02-08btrfs: rework the order of btrfs_ordered_extent::flagsQu Wenruo
[BUG] There is a long existing bug in the last parameter of btrfs_add_ordered_extent(), in commit 771ed689d2cd ("Btrfs: Optimize compressed writeback and reads") back to 2008. In that ancient commit btrfs_add_ordered_extent() expects the @type parameter to be one of the following: - BTRFS_ORDERED_REGULAR - BTRFS_ORDERED_NOCOW - BTRFS_ORDERED_PREALLOC - BTRFS_ORDERED_COMPRESSED But we pass 0 in cow_file_range(), which means BTRFS_ORDERED_IO_DONE. Ironically extra check in __btrfs_add_ordered_extent() won't set the bit if we see (type == IO_DONE || type == IO_COMPLETE), and avoid any obvious bug. But this still leads to regular COW ordered extent having no bit to indicate its type in various trace events, rendering REGULAR bit useless. [FIX] Change the following aspects to avoid such problem: - Reorder btrfs_ordered_extent::flags Now the type bits go first (REGULAR/NOCOW/PREALLCO/COMPRESSED), then DIRECT bit, finally extra status bits like IO_DONE/COMPLETE/IOERR. - Add extra ASSERT() for btrfs_add_ordered_extent_*() - Remove @type parameter for btrfs_add_ordered_extent_compress() As the only valid @type here is BTRFS_ORDERED_COMPRESSED. - Remove the unnecessary special check for IO_DONE/COMPLETE in __btrfs_add_ordered_extent() This is just to make the code work, with extra ASSERT(), there are limited values can be passed in. Reviewed-by: Nikolay Borisov <nborisov@suse.com> 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>
2021-02-08btrfs: remove redundant NULL check before kvfreeYang Li
Fix below warnings reported by coccicheck: ./fs/btrfs/raid56.c:237:2-8: WARNING: NULL check before some freeing functions is not needed. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Yang Li <abaci-bugfix@linux.alibaba.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: do not cleanup upper nodes in btrfs_backref_cleanup_nodeJosef Bacik
Zygo reported the following panic when testing my error handling patches for relocation: kernel BUG at fs/btrfs/backref.c:2545! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 3 PID: 8472 Comm: btrfs Tainted: G W 14 Hardware name: QEMU Standard PC (i440FX + PIIX, Call Trace: btrfs_backref_error_cleanup+0x4df/0x530 build_backref_tree+0x1a5/0x700 ? _raw_spin_unlock+0x22/0x30 ? release_extent_buffer+0x225/0x280 ? free_extent_buffer.part.52+0xd7/0x140 relocate_tree_blocks+0x2a6/0xb60 ? kasan_unpoison_shadow+0x35/0x50 ? do_relocation+0xc10/0xc10 ? kasan_kmalloc+0x9/0x10 ? kmem_cache_alloc_trace+0x6a3/0xcb0 ? free_extent_buffer.part.52+0xd7/0x140 ? rb_insert_color+0x342/0x360 ? add_tree_block.isra.36+0x236/0x2b0 relocate_block_group+0x2eb/0x780 ? merge_reloc_roots+0x470/0x470 btrfs_relocate_block_group+0x26e/0x4c0 btrfs_relocate_chunk+0x52/0x120 btrfs_balance+0xe2e/0x18f0 ? pvclock_clocksource_read+0xeb/0x190 ? btrfs_relocate_chunk+0x120/0x120 ? lock_contended+0x620/0x6e0 ? do_raw_spin_lock+0x1e0/0x1e0 ? do_raw_spin_unlock+0xa8/0x140 btrfs_ioctl_balance+0x1f9/0x460 btrfs_ioctl+0x24c8/0x4380 ? __kasan_check_read+0x11/0x20 ? check_chain_key+0x1f4/0x2f0 ? __asan_loadN+0xf/0x20 ? btrfs_ioctl_get_supported_features+0x30/0x30 ? kvm_sched_clock_read+0x18/0x30 ? check_chain_key+0x1f4/0x2f0 ? lock_downgrade+0x3f0/0x3f0 ? handle_mm_fault+0xad6/0x2150 ? do_vfs_ioctl+0xfc/0x9d0 ? ioctl_file_clone+0xe0/0xe0 ? check_flags.part.50+0x6c/0x1e0 ? check_flags.part.50+0x6c/0x1e0 ? check_flags+0x26/0x30 ? lock_is_held_type+0xc3/0xf0 ? syscall_enter_from_user_mode+0x1b/0x60 ? do_syscall_64+0x13/0x80 ? rcu_read_lock_sched_held+0xa1/0xd0 ? __kasan_check_read+0x11/0x20 ? __fget_light+0xae/0x110 __x64_sys_ioctl+0xc3/0x100 do_syscall_64+0x37/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This occurs because of this check if (RB_EMPTY_NODE(&upper->rb_node)) BUG_ON(!list_empty(&node->upper)); As we are dropping the backref node, if we discover that our upper node in the edge we just cleaned up isn't linked into the cache that we are now done with this node, thus the BUG_ON(). However this is an erroneous assumption, as we will look up all the references for a node first, and then process the pending edges. All of the 'upper' nodes in our pending edges won't be in the cache's rb_tree yet, because they haven't been processed. We could very well have many edges still left to cleanup on this node. The fact is we simply do not need this check, we can just process all of the edges only for this node, because below this check we do the following if (list_empty(&upper->lower)) { list_add_tail(&upper->lower, &cache->leaves); upper->lowest = 1; } If the upper node truly isn't used yet, then we add it to the cache->leaves list to be cleaned up later. If it is still used then the last child node that has it linked into its node will add it to the leaves list and then it will be cleaned up. Fix this problem by dropping this logic altogether. With this fix I no longer see the panic when testing with error injection in the backref code. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: keep track of the root owner for relocation readsJosef Bacik
While testing the error paths in relocation, I hit the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.10.0-rc3+ #206 Not tainted ------------------------------------------------------ btrfs-balance/1571 is trying to acquire lock: ffff8cdbcc8f77d0 (&head_ref->mutex){+.+.}-{3:3}, at: btrfs_lookup_extent_info+0x156/0x3b0 but task is already holding lock: ffff8cdbc54adbf8 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_lock+0x27/0x100 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (btrfs-tree-00){++++}-{3:3}: down_write_nested+0x43/0x80 __btrfs_tree_lock+0x27/0x100 btrfs_search_slot+0x248/0x890 relocate_tree_blocks+0x490/0x650 relocate_block_group+0x1ba/0x5d0 kretprobe_trampoline+0x0/0x50 -> #1 (btrfs-csum-01){++++}-{3:3}: down_read_nested+0x43/0x130 __btrfs_tree_read_lock+0x27/0x100 btrfs_read_lock_root_node+0x31/0x40 btrfs_search_slot+0x5ab/0x890 btrfs_del_csums+0x10b/0x3c0 __btrfs_free_extent+0x49d/0x8e0 __btrfs_run_delayed_refs+0x283/0x11f0 btrfs_run_delayed_refs+0x86/0x220 btrfs_start_dirty_block_groups+0x2ba/0x520 kretprobe_trampoline+0x0/0x50 -> #0 (&head_ref->mutex){+.+.}-{3:3}: __lock_acquire+0x1167/0x2150 lock_acquire+0x116/0x3e0 __mutex_lock+0x7e/0x7b0 btrfs_lookup_extent_info+0x156/0x3b0 walk_down_proc+0x1c3/0x280 walk_down_tree+0x64/0xe0 btrfs_drop_subtree+0x182/0x260 do_relocation+0x52e/0x660 relocate_tree_blocks+0x2ae/0x650 relocate_block_group+0x1ba/0x5d0 kretprobe_trampoline+0x0/0x50 other info that might help us debug this: Chain exists of: &head_ref->mutex --> btrfs-csum-01 --> btrfs-tree-00 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(btrfs-tree-00); lock(btrfs-csum-01); lock(btrfs-tree-00); lock(&head_ref->mutex); *** DEADLOCK *** 5 locks held by btrfs-balance/1571: #0: ffff8cdb89749ff8 (&fs_info->delete_unused_bgs_mutex){+.+.}-{3:3}, at: btrfs_balance+0x563/0xf40 #1: ffff8cdb89748838 (&fs_info->cleaner_mutex){+.+.}-{3:3}, at: btrfs_relocate_block_group+0x156/0x300 #2: ffff8cdbc2c16650 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x413/0x5c0 #3: ffff8cdbc135f538 (btrfs-treloc-01){+.+.}-{3:3}, at: __btrfs_tree_lock+0x27/0x100 #4: ffff8cdbc54adbf8 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_lock+0x27/0x100 stack backtrace: CPU: 1 PID: 1571 Comm: btrfs-balance Not tainted 5.10.0-rc3+ #206 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack+0x8b/0xb0 check_noncircular+0xcf/0xf0 ? trace_call_bpf+0x139/0x260 __lock_acquire+0x1167/0x2150 lock_acquire+0x116/0x3e0 ? btrfs_lookup_extent_info+0x156/0x3b0 __mutex_lock+0x7e/0x7b0 ? btrfs_lookup_extent_info+0x156/0x3b0 ? btrfs_lookup_extent_info+0x156/0x3b0 ? release_extent_buffer+0x124/0x170 ? _raw_spin_unlock+0x1f/0x30 ? release_extent_buffer+0x124/0x170 btrfs_lookup_extent_info+0x156/0x3b0 walk_down_proc+0x1c3/0x280 walk_down_tree+0x64/0xe0 btrfs_drop_subtree+0x182/0x260 do_relocation+0x52e/0x660 relocate_tree_blocks+0x2ae/0x650 ? add_tree_block+0x149/0x1b0 relocate_block_group+0x1ba/0x5d0 elfcorehdr_read+0x40/0x40 ? elfcorehdr_read+0x40/0x40 ? btrfs_balance+0x796/0xf40 ? __kthread_parkme+0x66/0x90 ? btrfs_balance+0xf40/0xf40 ? balance_kthread+0x37/0x50 ? kthread+0x137/0x150 ? __kthread_bind_mask+0x60/0x60 ? ret_from_fork+0x1f/0x30 As you can see this is bogus, we never take another tree's lock under the csum lock. This happens because sometimes we have to read tree blocks from disk without knowing which root they belong to during relocation. We defaulted to an owner of 0, which translates to an fs tree. This is fine as all fs trees have the same class, but obviously isn't fine if the block belongs to a COW only tree. Thankfully COW only trees only have their owners root as a reference to them, and since we already look up the extent information during relocation, go ahead and check and see if this block might belong to a COW only tree, and if so save the owner in the tree_block struct. This allows us to read_tree_block with the proper owner, which gets rid of this lockdep splat. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: introduce helper to grab an existing extent buffer from a pageQu Wenruo
This patch will extract the code to grab an extent buffer from a page into a helper, grab_extent_buffer_from_page(). This reduces one indent level, and provides the work place for later expansion for subapge support. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: update comment for btrfs_dirty_pagesQu Wenruo
The original comment is from the initial merge, which has several problems: - No holes check any more - No inline decision is made Update the out-of-date comment with more correct one. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: refactor __extent_writepage_io() to improve readabilityQu Wenruo
The refactoring involves the following modifications: - iosize alignment In fact we don't really need to manually do alignment at all. All extent maps should already be aligned, thus basic ASSERT() check would be enough. - redundant variables We have extra variable like blocksize/pg_offset/end. They are all unnecessary. @blocksize can be replaced by sectorsize size directly, and it's only used to verify the em start/size is aligned. @pg_offset can be easily calculated using @cur and page_offset(page). @end is just assigned from @page_end and never modified, use "start + PAGE_SIZE - 1" directly and remove @page_end. - remove some BUG_ON()s The BUG_ON()s are for extent map, which we have tree-checker to check on-disk extent data item and runtime check. ASSERT() should be enough. 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>
2021-02-08btrfs: rename parameter offset to disk_bytenr in submit_extent_pageQu Wenruo
The parameter offset is confusing, it's supposed to be the disk bytenr of metadata/data. Rename it to disk_bytenr and update the comment. Also rename each offset passed to submit_extent_page() as @disk_bytenr so they're consistent. 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>
2021-02-08btrfs: refactor btrfs_dec_test_* functions for ordered extentsQu Wenruo
The refactoring involves the following modifications: - Return bool instead of int - Parameter update for @cached of btrfs_dec_test_first_ordered_pending() For btrfs_dec_test_first_ordered_pending(), @cached is only used to return the finished ordered extent. Rename it to @finished_ret. - Comment updates * Change one stale comment Which still refers to btrfs_dec_test_ordered_pending(), but the context is calling btrfs_dec_test_first_ordered_pending(). * Follow the common comment style for both functions Add more detailed descriptions for parameters and the return value * Move the reason why test_and_set_bit() is used into the call sites - Change how the return value is calculated The most anti-human part of the return value is: if (...) ret = 1; ... return ret == 0; This means, when we set ret to 1, the function returns 0. Change the local variable name to @finished, and directly return the value of it. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: make btrfs_dio_private::bytes u32Qu Wenruo
btrfs_dio_private::bytes is only assigned from bio::bi_iter::bi_size, which is never larger than U32. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: remove always true condition in btrfs_start_delalloc_rootsNikolay Borisov
Following the rework in e076ab2a2ca7 ("btrfs: shrink delalloc pages instead of full inodes") the nr variable is no longer passed by reference to start_delalloc_inodes hence it cannot change. Additionally we are always guaranteed for it to be positive number hence it's redundant to have it as a condition in the loop. Simply remove that usage. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: make btrfs_start_delalloc_root's nr argument a longNikolay Borisov
It's currently u64 which gets instantly translated either to LONG_MAX (if U64_MAX is passed) or cast to an unsigned long (which is in fact, wrong because writeback_control::nr_to_write is a signed, long type). Just convert the function's argument to be long time which obviates the need to manually convert u64 value to a long. Adjust all call sites which pass U64_MAX to pass LONG_MAX. Finally ensure that in shrink_delalloc the u64 is converted to a long without overflowing, resulting in a negative number. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: send: remove stale code when checking for shared extentsFilipe Manana
After commit 040ee6120cb670 ("Btrfs: send, improve clone range") we do not use anymore the data_offset field of struct backref_ctx, as after that we do all the necessary checks for the data offset of file extent items at clone_range(). Since there are no more users of data_offset from that structure, remove it. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: consolidate btrfs_previous_item ret val handling in btrfs_shrink_deviceNikolay Borisov
Instead of having three 'if' to handle non-NULL return value consolidate this in one 'if (ret)'. That way the code is more obvious: - Always drop delete_unused_bgs_mutex if ret is not NULL - If ret is negative -> goto done - If it's 1 -> reset ret to 0, release the path and finish the loop. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: ref-verify: make sure owner is set for all refsJosef Bacik
I noticed that shared ref entries in ref-verify didn't have the proper owner set, which caused me to think there was something seriously wrong. However the problem is if we have a parent we simply weren't filling out the owner part of the reference, even though we have it. Fix this by making sure we set all the proper fields when we modify a reference, this way we'll have the proper owner if a problem happens and we don't waste time thinking we're updating the wrong level. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: ref-verify: pass down tree block level when building refsJosef Bacik
I noticed that sometimes I would have the wrong level printed out with ref-verify while testing some error injection related problems. This is because we only get the level from the main extent item, but our references could go off the current leaf into another, and at that point we lose our level. Fix this by keeping track of the last tree block level that we found, the same way we keep track of our bytenr and num_bytes, in case we happen to wander into another leaf while still processing the references for a bytenr. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: noinline btrfs_should_cancel_balanceJosef Bacik
I was attempting to reproduce a problem that Zygo hit, but my error injection wasn't firing for a few of the common calls to btrfs_should_cancel_balance. This is because the compiler decided to inline it at these spots. Keep this from happening by explicitly marking the function as noinline so that error injection will always work. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: allow error injection for btrfs_search_slot and btrfs_cow_blockJosef Bacik
The following patches are going to address error handling in relocation, in order to test those patches I need to be able to inject errors in btrfs_search_slot and btrfs_cow_block, as we call both of these pretty often in different cases during relocation. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: remove new_dirid argument from btrfs_create_subvol_rootNikolay Borisov
It's no longer used. While at it also remove new_dirid in create_subvol as it's used in a single place and open code it. No functional changes. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: make btrfs_root::free_objectid hold the next available objectidNikolay Borisov
Adjust the way free_objectid is being initialized, it now stores BTRFS_FIRST_FREE_OBJECTID rather than the, somewhat arbitrary, BTRFS_FIRST_FREE_OBJECTID - 1. This change also has the added benefit that now it becomes unnecessary to explicitly initialize free_objectid for a newly create fs root. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: rename btrfs_root::highest_objectid to free_objectidNikolay Borisov
This reflects the true purpose of the member as it's being used solely in context where a new objectid is being allocated. Future changes will also change the way it's being used to closely follow this semantics. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: rename btrfs_find_free_objectid to btrfs_get_free_objectidNikolay Borisov
This better reflects the semantics of the function i.e no search is performed whatsoever. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: rename btrfs_find_highest_objectid to btrfs_init_root_free_objectidNikolay Borisov
This function is used to initialize the in-memory btrfs_root::highest_objectid member, which is used to get an available objectid. Rename it to better reflect its semantics. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: cleanup local variables in btrfs_file_write_iterNikolay Borisov
First replace all inode instances with a pointer to btrfs_inode. This removes multiple invocations of the BTRFS_I macro, subsequently remove 2 local variables as they are called only once and simply refer to them directly. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: clarify error returns values in __load_free_space_cacheZhihao Cheng
Return value in __load_free_space_cache is not properly set after (unlikely) memory allocation failures and 0 is returned instead. This is not a problem for the caller load_free_space_cache because only value 1 is considered as 'cache loaded' but for clarity it's better to set the errors accordingly. Fixes: a67509c30079 ("Btrfs: add a io_ctl struct and helpers for dealing with the space cache") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: fix error handling in commit_fs_rootsJosef Bacik
While doing error injection I would sometimes get a corrupt file system. This is because I was injecting errors at btrfs_search_slot, but would only do it one time per stack. This uncovered a problem in commit_fs_roots, where if we get an error we would just break. However we're in a nested loop, the first loop being a loop to find all the dirty fs roots, and then subsequent root updates would succeed clearing the error value. This isn't likely to happen in real scenarios, however we could potentially get a random ENOMEM once and then not again, and we'd end up with a corrupted file system. Fix this by moving the error checking around a bit to the main loop, as this is the only place where something will fail, and return the error as soon as it occurs. With this patch my reproducer no longer corrupts the file system. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-01-29Merge tag 'for-5.11-rc5-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few more fixes for a late rc: - fix lockdep complaint on 32bit arches and also remove an unsafe memory use due to device vs filesystem lifetime - two fixes for free space tree: * race during log replay and cache rebuild, now more likely to happen due to changes in this dev cycle * possible free space tree corruption with online conversion during initial tree population" * tag 'for-5.11-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix log replay failure due to race with space cache rebuild btrfs: fix lockdep warning due to seqcount_mutex on 32bit arch btrfs: fix possible free space tree corruption with online conversion
2021-01-25btrfs: fix log replay failure due to race with space cache rebuildFilipe Manana
After a sudden power failure we may end up with a space cache on disk that is not valid and needs to be rebuilt from scratch. If that happens, during log replay when we attempt to pin an extent buffer from a log tree, at btrfs_pin_extent_for_log_replay(), we do not wait for the space cache to be rebuilt through the call to: btrfs_cache_block_group(cache, 1); That is because that only waits for the task (work queue job) that loads the space cache to change the cache state from BTRFS_CACHE_FAST to any other value. That is ok when the space cache on disk exists and is valid, but when the cache is not valid and needs to be rebuilt, it ends up returning as soon as the cache state changes to BTRFS_CACHE_STARTED (done at caching_thread()). So this means that we can end up trying to unpin a range which is not yet marked as free in the block group. This results in the call to btrfs_remove_free_space() to return -EINVAL to btrfs_pin_extent_for_log_replay(), which in turn makes the log replay fail as well as mounting the filesystem. More specifically the -EINVAL comes from free_space_cache.c:remove_from_bitmap(), because the requested range is not marked as free space (ones in the bitmap), we have the following condition triggered: static noinline int remove_from_bitmap(struct btrfs_free_space_ctl *ctl, (...) if (ret < 0 || search_start != *offset) return -EINVAL; (...) It's the "search_start != *offset" that results in the condition being evaluated to true. When this happens we got the following in dmesg/syslog: [72383.415114] BTRFS: device fsid 32b95b69-0ea9-496a-9f02-3f5a56dc9322 devid 1 transid 1432 /dev/sdb scanned by mount (3816007) [72383.417837] BTRFS info (device sdb): disk space caching is enabled [72383.418536] BTRFS info (device sdb): has skinny extents [72383.423846] BTRFS info (device sdb): start tree-log replay [72383.426416] BTRFS warning (device sdb): block group 30408704 has wrong amount of free space [72383.427686] BTRFS warning (device sdb): failed to load free space cache for block group 30408704, rebuilding it now [72383.454291] BTRFS: error (device sdb) in btrfs_recover_log_trees:6203: errno=-22 unknown (Failed to pin buffers while recovering log root tree.) [72383.456725] BTRFS: error (device sdb) in btrfs_replay_log:2253: errno=-22 unknown (Failed to recover log tree) [72383.460241] BTRFS error (device sdb): open_ctree failed We also mark the range for the extent buffer in the excluded extents io tree. That is fine when the space cache is valid on disk and we can load it, in which case it causes no problems. However, for the case where we need to rebuild the space cache, because it is either invalid or it is missing, having the extent buffer range marked in the excluded extents io tree leads to a -EINVAL failure from the call to btrfs_remove_free_space(), resulting in the log replay and mount to fail. This is because by having the range marked in the excluded extents io tree, the caching thread ends up never adding the range of the extent buffer as free space in the block group since the calls to add_new_free_space(), called from load_extent_tree_free(), filter out any ranges that are marked as excluded extents. So fix this by making sure that during log replay we wait for the caching task to finish completely when we need to rebuild a space cache, and also drop the need to mark the extent buffer range in the excluded extents io tree, as well as clearing ranges from that tree at btrfs_finish_extent_commit(). This started to happen with some frequency on large filesystems having block groups with a lot of fragmentation since the recent commit e747853cae3ae3 ("btrfs: load free space cache asynchronously"), but in fact the issue has been there for years, it was just much less likely to happen. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-01-25btrfs: fix lockdep warning due to seqcount_mutex on 32bit archSu Yue
This effectively reverts commit d5c8238849e7 ("btrfs: convert data_seqcount to seqcount_mutex_t"). While running fstests on 32 bits test box, many tests failed because of warnings in dmesg. One of those warnings (btrfs/003): [66.441317] WARNING: CPU: 6 PID: 9251 at include/linux/seqlock.h:279 btrfs_remove_chunk+0x58b/0x7b0 [btrfs] [66.441446] CPU: 6 PID: 9251 Comm: btrfs Tainted: G O 5.11.0-rc4-custom+ #5 [66.441449] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.14.0-1 04/01/2014 [66.441451] EIP: btrfs_remove_chunk+0x58b/0x7b0 [btrfs] [66.441472] EAX: 00000000 EBX: 00000001 ECX: c576070c EDX: c6b15803 [66.441475] ESI: 10000000 EDI: 00000000 EBP: c56fbcfc ESP: c56fbc70 [66.441477] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010246 [66.441481] CR0: 80050033 CR2: 05c8da20 CR3: 04b20000 CR4: 00350ed0 [66.441485] Call Trace: [66.441510] btrfs_relocate_chunk+0xb1/0x100 [btrfs] [66.441529] ? btrfs_lookup_block_group+0x17/0x20 [btrfs] [66.441562] btrfs_balance+0x8ed/0x13b0 [btrfs] [66.441586] ? btrfs_ioctl_balance+0x333/0x3c0 [btrfs] [66.441619] ? __this_cpu_preempt_check+0xf/0x11 [66.441643] btrfs_ioctl_balance+0x333/0x3c0 [btrfs] [66.441664] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [66.441683] btrfs_ioctl+0x414/0x2ae0 [btrfs] [66.441700] ? __lock_acquire+0x35f/0x2650 [66.441717] ? lockdep_hardirqs_on+0x87/0x120 [66.441720] ? lockdep_hardirqs_on_prepare+0xd0/0x1e0 [66.441724] ? call_rcu+0x2d3/0x530 [66.441731] ? __might_fault+0x41/0x90 [66.441736] ? kvm_sched_clock_read+0x15/0x50 [66.441740] ? sched_clock+0x8/0x10 [66.441745] ? sched_clock_cpu+0x13/0x180 [66.441750] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [66.441750] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [66.441768] __ia32_sys_ioctl+0x165/0x8a0 [66.441773] ? __this_cpu_preempt_check+0xf/0x11 [66.441785] ? __might_fault+0x89/0x90 [66.441791] __do_fast_syscall_32+0x54/0x80 [66.441796] do_fast_syscall_32+0x32/0x70 [66.441801] do_SYSENTER_32+0x15/0x20 [66.441805] entry_SYSENTER_32+0x9f/0xf2 [66.441808] EIP: 0xab7b5549 [66.441814] EAX: ffffffda EBX: 00000003 ECX: c4009420 EDX: bfa91f5c [66.441816] ESI: 00000003 EDI: 00000001 EBP: 00000000 ESP: bfa91e98 [66.441818] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00000292 [66.441833] irq event stamp: 42579 [66.441835] hardirqs last enabled at (42585): [<c60eb065>] console_unlock+0x495/0x590 [66.441838] hardirqs last disabled at (42590): [<c60eafd5>] console_unlock+0x405/0x590 [66.441840] softirqs last enabled at (41698): [<c601b76c>] call_on_stack+0x1c/0x60 [66.441843] softirqs last disabled at (41681): [<c601b76c>] call_on_stack+0x1c/0x60 ======================================================================== btrfs_remove_chunk+0x58b/0x7b0: __seqprop_mutex_assert at linux/./include/linux/seqlock.h:279 (inlined by) btrfs_device_set_bytes_used at linux/fs/btrfs/volumes.h:212 (inlined by) btrfs_remove_chunk at linux/fs/btrfs/volumes.c:2994 ======================================================================== The warning is produced by lockdep_assert_held() in __seqprop_mutex_assert() if CONFIG_LOCKDEP is enabled. And "olumes.c:2994 is btrfs_device_set_bytes_used() with mutex lock fs_info->chunk_mutex held already. After adding some debug prints, the cause was found that many __alloc_device() are called with NULL @fs_info (during scanning ioctl). Inside the function, btrfs_device_data_ordered_init() is expanded to seqcount_mutex_init(). In this scenario, its second parameter info->chunk_mutex is &NULL->chunk_mutex which equals to offsetof(struct btrfs_fs_info, chunk_mutex) unexpectedly. Thus, seqcount_mutex_init() is called in wrong way. And later btrfs_device_get/set helpers trigger lockdep warnings. The device and filesystem object lifetimes are different and we'd have to synchronize initialization of the btrfs_device::data_seqcount with the fs_info, possibly using some additional synchronization. It would still not prevent concurrent access to the seqcount lock when it's used for read and initialization. Commit d5c8238849e7 ("btrfs: convert data_seqcount to seqcount_mutex_t") does not mention a particular problem being fixed so revert should not cause any harm and we'll get the lockdep warning fixed. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=210139 Reported-by: Erhard F <erhard_f@mailbox.org> Fixes: d5c8238849e7 ("btrfs: convert data_seqcount to seqcount_mutex_t") CC: stable@vger.kernel.org # 5.10 CC: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Su Yue <l@damenly.su> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-01-25btrfs: fix possible free space tree corruption with online conversionJosef Bacik
While running btrfs/011 in a loop I would often ASSERT() while trying to add a new free space entry that already existed, or get an EEXIST while adding a new block to the extent tree, which is another indication of double allocation. This occurs because when we do the free space tree population, we create the new root and then populate the tree and commit the transaction. The problem is when you create a new root, the root node and commit root node are the same. During this initial transaction commit we will run all of the delayed refs that were paused during the free space tree generation, and thus begin to cache block groups. While caching block groups the caching thread will be reading from the main root for the free space tree, so as we make allocations we'll be changing the free space tree, which can cause us to add the same range twice which results in either the ASSERT(ret != -EEXIST); in __btrfs_add_free_space, or in a variety of different errors when running delayed refs because of a double allocation. Fix this by marking the fs_info as unsafe to load the free space tree, and fall back on the old slow method. We could be smarter than this, for example caching the block group while we're populating the free space tree, but since this is a serious problem I've opted for the simplest solution. CC: stable@vger.kernel.org # 4.9+ Fixes: a5ed91828518 ("Btrfs: implement the free space B-tree") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>