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This WARN_ON(ret) is never executed since the previous if statement makes us jump into the 'out_put' label when ret is not zero. The existing transaction abort inside the if statement also gives us a stack trace, so we don't need to move the WARN_ON(ret) into the if statement either. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Remove duplicate inclusion of delayed-inode.h in disk-io.c to clean up redundant code. Signed-off-by: Chen Ni <nichen@iscas.ac.cn> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to pass the maximum between the block group's start offset and BTRFS_SUPER_INFO_OFFSET (64K) since we can't have any block groups allocated in the first megabyte, as that's reserved space. Furthermore, even if we could, the correct thing to do was to pass the block group's start offset anyway - and that's precisely what we do for block groups hat happen to contain a superblock mirror (the range for the super block is never marked as free and it's marked as dirty in the fs_info->excluded_extents io tree). So simplify this and get rid of that maximum expression. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_extent_root() can return a NULL pointer in case the root we are looking for is not in the rb tree that tracks roots. So add checks to every caller that is missing such check to log a message and return an error. The same applies to callers of btrfs_block_group_root(), since it calls btrfs_extent_root(). Reported-by: Chris Mason <clm@meta.com> Link: https://lore.kernel.org/linux-btrfs/20260208161657.3972997-1-clm@meta.com/ Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_csum_root() can return a NULL pointer in case the root we are looking for is not in the rb tree that tracks roots. So add checks to every caller that is missing such check to log a message and return an error. Reported-by: Chris Mason <clm@meta.com> Link: https://lore.kernel.org/linux-btrfs/20260208161657.3972997-1-clm@meta.com/ Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
There is a lengthy comment introduced in commit b3ff8f1 ("btrfs: Don't submit any btree write bio if the fs has errors") and commit c9583ad ("btrfs: avoid double clean up when submit_one_bio() failed"), explaining two things: - Why we don't want to submit metadata write if the fs has errors - Why we re-set @ret to 0 if it's positive However it's no longer uptodate by the following reasons: - We have better checks nowadays Commit 2618849 ("btrfs: ensure no dirty metadata is written back for an fs with errors") has introduced better checks, that if the fs is in an error state, metadata writes will not result in any bio but instead complete immediately. That covers all metadata writes better. - Mentioned incorrect function name The commit c9583ad ("btrfs: avoid double clean up when submit_one_bio() failed") introduced this ret > 0 handling, but at that time the function name submit_extent_page() was already incorrect. It was submit_eb_page() that could return >0 at that time, and submit_extent_page() could only return 0 or <0 for errors, never >0. Later commit b35397d ("btrfs: convert submit_extent_page() to use a folio") changed "submit_extent_page()" to "submit_extent_folio()" in the comment, but it doesn't make any difference since the function name is wrong from day 1. Finally commit 5e121ae ("btrfs: use buffer xarray for extent buffer writeback operations") completely reworked how metadata writeback works, and removed submit_eb_page(), leaving only the wrong function name in the comment. Furthermore the function submit_extent_folio() still exists in the latest code base, but is never utilized for metadata writeback, causing more confusion. Just remove the lengthy comment, and replace the "if (ret > 0)" check with an ASSERT(), since only btrfs_check_meta_write_pointer() can modify @ret and it returns 0 or <0 for errors. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
…ent() We already have btrfs_ordered_extent::inode, thus there is no need to pass a btrfs_inode parameter to btrfs_remove_ordered_extent(). Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
We compared rfer_cmpr against excl_cmpr_sum instead of rfer_cmpr_sum which is confusing. I expect that rfer_cmpr == excl_cmpr in squota, but it is much better to be consistent in case of any surprises or bugs. Reported-by: Chris Mason <clm@meta.com> Link: https://lore.kernel.org/linux-btrfs/cover.1764796022.git.boris@bur.io/T/#mccb231643ffd290b44a010d4419474d280be5537 Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com>
Both functions btrfs_finish_ordered_extent() and btrfs_mark_ordered_io_finished() are accepting an optional folio parameter. That @Folio is passed into can_finish_ordered_extent(), which later will test and clear the ordered flag for the involved range. However I do not think there is any other call site that can clear ordered flags of an page cache folio and can affect can_finish_ordered_extent(). There are limited *_clear_ordered() callers out of can_finish_ordered_extent() function: - btrfs_migrate_folio() This is completely unrelated, it's just migrating the ordered flag to the new folio. - btrfs_cleanup_ordered_extents() We manually clean the ordered flags of all involved folios, then call btrfs_mark_ordered_io_finished() without a @Folio parameter. So it doesn't need and didn't pass a @Folio parameter in the first place. - btrfs_writepage_fixup_worker() This function is going to be removed soon, and we should not hit that function anymore. - btrfs_invalidate_folio() This is the real call site we need to bother with. If we already have a bio running, btrfs_finish_ordered_extent() in end_bbio_data_write() will be executed first, as btrfs_invalidate_folio() will wait for the writeback to finish. Thus if there is a running bio, it will not see the range has ordered flags, and just skip to the next range. If there is no bio running, meaning the ordered extent is created but the folio is not yet submitted. In that case btrfs_invalidate_folio() will manually clear the folio ordered range, but then manually finish the ordered extent with btrfs_dec_test_ordered_pending() without bothering the folio ordered flags. Meaning if the OE range with folio ordered flags will be finished manually without the need to call can_finish_ordered_extent(). This means all can_finish_ordered_extent() call sites should get a range that has folio ordered flag set, thus the old "return false" branch should never be triggered. Now we can: - Remove the @Folio parameter from involved functions * btrfs_mark_ordered_io_finished() * btrfs_finish_ordered_extent() For call sites passing a @Folio into those functions, let them manually clear the ordered flag of involved folios. - Move btrfs_finish_ordered_extent() out of the loop in end_bbio_data_write() We only need to call btrfs_finish_ordered_extent() once per bbio, not per folio. - Add an ASSERT() to make sure all folio ranges have ordered flags It's only for end_bbio_data_write(). And we already have enough safe nets to catch over-accounting of ordered extents. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
[BUG] The following sequence will set the file with nocompress flag: # mkfs.btrfs -f $dev # mount $dev $mnt -o max_inline=4,compress # xfs_io -f -c "pwrite 0 2k" -c sync $mnt/foobar The inode will have NOCOMPRESS flag, even if the content itself (all 0xcd) can still be compressed very well: item 4 key (257 INODE_ITEM 0) itemoff 15879 itemsize 160 generation 9 transid 10 size 2097152 nbytes 1052672 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 257 flags 0x8(NOCOMPRESS) Please note that, this behavior is there even before commit 59615e2 ("btrfs: reject single block sized compression early"). [CAUSE] At compress_file_range(), after btrfs_compress_folios() call, we try making an inlined extent by calling cow_file_range_inline(). But cow_file_range_inline() calls can_cow_file_range_inline() which has more accurate checks on if the range can be inlined. One of the user configurable conditions is the "max_inline=" mount option. If that value is set low (like the example, 4 bytes, which cannot store any header), or the compressed content is just slightly larger than 2K (the default value, meaning a 50% compression ratio), cow_file_range_inline() will return 1 immediately. And since we're here only to try inline the compressed data, the range is no larger than a single fs block. Thus compression is never going to make it a win, we fall back to marking the inode incompressible unavoidably. [FIX] Just add an extra check after inline attempt, so that if the inline attempt failed, do not set the nocompress flag. As there is no way to remove that flag, and the default 50% compression ratio is way too strict for the whole inode. CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
In this function the 'pages' object is never freed in the hopes that it is picked up by btrfs_uring_read_finished() whenever that executes in the future. But that's just the happy path. Along the way previous allocations might have gone wrong, or we might not get -EIOCBQUEUED from btrfs_encoded_read_regular_fill_pages(). In all these cases, we go to a cleanup section that frees all memory allocated by this function without assuming any deferred execution, and this also needs to happen for the 'pages' allocation. Fixes: 34310c4 ("btrfs: add io_uring command for encoded reads (ENCODED_READ ioctl)") Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
When a snapshot is being created, the atomic counter snapshot_force_cow is incremented to force incoming writes to fallback to COW. This is a critical mechanism to protect the consistency of the snapshot being taken. Currently, can_nocow_file_extent() checks this counter only after performing several checks, most notably the expensive cross-reference check via btrfs_cross_ref_exist(). btrfs_cross_ref_exist() releases the path and performs a search in the extent tree or backref cache, which involves btree traversals and locking overhead. Moves the snapshot_force_cow check to the very beginning of can_nocow_file_extent(). This reordering is safe and beneficial because: 1. args->writeback_path is invariant for the duration of the call (set by caller run_delalloc_nocow). 2. is_freespace_inode is a static property of the inode. 3. The state of snapshot_force_cow is driven by the btrfs_mksnapshot() process. Checking it earlier does not change the outcome of the NOCOW decision, but effectively prunes the expensive code path when a fallback to COW is inevitable. By failing fast when a snapshot is pending, we avoid the unnecessary overhead of btrfs_cross_ref_exist() and other extent item checks in the scenario where NOCOW is already known to be impossible. Signed-off-by: Chen Guan Jie <jk.chen1095@gmail.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
…stem When unmounting a filesystem we will try, among many other things, to commit the super block. On a filesystem that was shutdown, though, this will always fail with -EROFS as writes are forbidden on this context; and an error will be reported. Don't commit the super block on this situation, which should be fine as the filesystem is frozen before shutdown and, therefore, it should be at a consistent state. Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
…dir_index() Fix the error message in btrfs_delete_delayed_dir_index() if __btrfs_add_delayed_item() fails: the message says root, inode, index, error, but we're actually passing index, root, inode, error. Fixes: adc1ef5 ("btrfs: add details to error messages at btrfs_delete_delayed_dir_index()") Signed-off-by: Mark Harmstone <mark@harmstone.com> Reviewed-by: Filipe Manana <fdmanana@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>
Currently our qgroup ioctls don't reserve any space, they just do a
transaction join, which does not reserve any space, neither for the quota
tree updates nor for the delayed refs generated when updating the quota
tree. The quota root uses the global block reserve, which is fine most of
the time since we don't expect a lot of updates to the quota root, or to
be too close to -ENOSPC such that other critical metadata updates need to
resort to the global reserve.
However this is not optimal, as not reserving proper space may result in a
transaction abort due to not reserving space for delayed refs and then
abusing the use of the global block reserve.
For example, the following reproducer (which is unlikely to model any
real world use case, but just to illustrate the problem), triggers such a
transaction abort due to -ENOSPC when running delayed refs:
$ cat test.sh
#!/bin/bash
DEV=/dev/nullb0
MNT=/mnt/nullb0
umount $DEV &> /dev/null
# Limit device to 1G so that it's much faster to reproduce the issue.
mkfs.btrfs -f -b 1G $DEV
mount -o commit=600 $DEV $MNT
fallocate -l 800M $MNT/filler
btrfs quota enable $MNT
for ((i = 1; i <= 400000; i++)); do
btrfs qgroup create 1/$i $MNT
done
umount $MNT
When running this, we can see in dmesg/syslog that a transaction abort
happened:
[436.490] BTRFS error (device nullb0): failed to run delayed ref for logical 30408704 num_bytes 16384 type 176 action 1 ref_mod 1: -28
[436.493] ------------[ cut here ]------------
[436.494] BTRFS: Transaction aborted (error -28)
[436.495] WARNING: fs/btrfs/extent-tree.c:2247 at btrfs_run_delayed_refs+0xd9/0x110 [btrfs], CPU#4: umount/2495372
[436.497] Modules linked in: btrfs loop (...)
[436.508] CPU: 4 UID: 0 PID: 2495372 Comm: umount Tainted: G W 6.19.0-rc8-btrfs-next-225+ #1 PREEMPT(full)
[436.510] Tainted: [W]=WARN
[436.511] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
[436.513] RIP: 0010:btrfs_run_delayed_refs+0xdf/0x110 [btrfs]
[436.514] Code: 0f 82 ea (...)
[436.518] RSP: 0018:ffffd511850b7d78 EFLAGS: 00010292
[436.519] RAX: 00000000ffffffe4 RBX: ffff8f120dad37e0 RCX: 0000000002040001
[436.520] RDX: 0000000000000002 RSI: 00000000ffffffe4 RDI: ffffffffc090fd80
[436.522] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffffc04d1867
[436.523] R10: ffff8f18dc1fffa8 R11: 0000000000000003 R12: ffff8f173aa89400
[436.524] R13: 0000000000000000 R14: ffff8f173aa89400 R15: 0000000000000000
[436.526] FS: 00007fe59045d840(0000) GS:ffff8f192e22e000(0000) knlGS:0000000000000000
[436.527] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[436.528] CR2: 00007fe5905ff2b0 CR3: 000000060710a002 CR4: 0000000000370ef0
[436.530] Call Trace:
[436.530] <TASK>
[436.530] btrfs_commit_transaction+0x73/0xc00 [btrfs]
[436.531] ? btrfs_attach_transaction_barrier+0x1e/0x70 [btrfs]
[436.532] sync_filesystem+0x7a/0x90
[436.533] generic_shutdown_super+0x28/0x180
[436.533] kill_anon_super+0x12/0x40
[436.534] btrfs_kill_super+0x12/0x20 [btrfs]
[436.534] deactivate_locked_super+0x2f/0xb0
[436.534] cleanup_mnt+0xea/0x180
[436.535] task_work_run+0x58/0xa0
[436.535] exit_to_user_mode_loop+0xed/0x480
[436.536] ? __x64_sys_umount+0x68/0x80
[436.536] do_syscall_64+0x2a5/0xf20
[436.537] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[436.537] RIP: 0033:0x7fe5906b6217
[436.538] Code: 0d 00 f7 (...)
[436.540] RSP: 002b:00007ffcd87a61f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[436.541] RAX: 0000000000000000 RBX: 00005618b9ecadc8 RCX: 00007fe5906b6217
[436.541] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00005618b9ecb100
[436.542] RBP: 0000000000000000 R08: 00007ffcd87a4fe0 R09: 00000000ffffffff
[436.544] R10: 0000000000000103 R11: 0000000000000246 R12: 00007fe59081626c
[436.544] R13: 00005618b9ecb100 R14: 0000000000000000 R15: 00005618b9ecacc0
[436.545] </TASK>
[436.545] ---[ end trace 0000000000000000 ]---
Fix this by changing the qgroup ioctls to use start transaction instead of
joining so that proper space is reserved for the delayed refs generated
for the updates to the quota root. This way we don't get any transaction
abort.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
…item() Fix the error message in check_dev_extent_item(), when an overlapping stripe is encountered. For dev extents, objectid is the disk number and offset the physical address, so prev_key->objectid should actually be prev_key->offset. (I can't take any credit for this one - this was discovered by Chris and his friend Claude.) Reported-by: Chris Mason <clm@fb.com> Fixes: 008e251 ("btrfs: tree-checker: add dev extent item checks") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Mark Harmstone <mark@harmstone.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Fix a copy-paste error in check_extent_data_ref(): we're printing root as in the message above, we should be printing objectid. Fixes: f333a3c ("btrfs: tree-checker: validate dref root and objectid") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Mark Harmstone <mark@harmstone.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Fix the superblock offset mismatch error message in btrfs_validate_super(): we changed it so that it considers all the superblocks, but the message still assumes we're only looking at the first one. The change from %u to %llu is because we're changing from a constant to a u64. Fixes: 069ec95 ("btrfs: Refactor btrfs_check_super_valid") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Mark Harmstone <mark@harmstone.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Commit b471965 fixed the comparison in scrub_verify_one_metadata to use metadata_uuid rather than fsid, but left the warning as it was. Fix it so it matches what we're doing. Fixes: b471965 ("btrfs: fix replace/scrub failure with metadata_uuid") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Mark Harmstone <mark@harmstone.com> Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to COW the root node of the subvolume we are snaphotting because we then call btrfs_copy_root(), which creates a copy of the root node and sets its generation to the current transaction. So remove this redudant COW right before calling btrfs_copy_root(), saving one extent allocation, memory allocation, copying things, etc, and making the code less confusing. Also rename the extent buffer variable from "old" to "root_eb" since that name no longer makes any sense after removing the unnecessary COW operation. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com>
[BUG] When running btrfs/284 with 64K page size and 4K fs block size, the following ASSERT() can be triggered: assertion failed: cb->bbio.bio.bi_iter.bi_size == disk_num_bytes :: 0, in inode.c:9991 ------------[ cut here ]------------ kernel BUG at inode.c:9991! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 5 UID: 0 PID: 6787 Comm: btrfs Tainted: G OE 6.19.0-rc8-custom+ #1 PREEMPT(voluntary) Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 pc : btrfs_do_encoded_write+0x9b0/0x9c0 [btrfs] lr : btrfs_do_encoded_write+0x9b0/0x9c0 [btrfs] Call trace: btrfs_do_encoded_write+0x9b0/0x9c0 [btrfs] (P) btrfs_do_write_iter+0x1d8/0x208 [btrfs] btrfs_ioctl_encoded_write+0x3c8/0x6d0 [btrfs] btrfs_ioctl+0xeb0/0x2b60 [btrfs] __arm64_sys_ioctl+0xac/0x110 invoke_syscall.constprop.0+0x64/0xe8 el0_svc_common.constprop.0+0x40/0xe8 do_el0_svc+0x24/0x38 el0_svc+0x3c/0x1b8 el0t_64_sync_handler+0xa0/0xe8 el0t_64_sync+0x1a4/0x1a8 Code: 91180021 90001080 9111a000 94039d54 (d4210000) ---[ end trace 0000000000000000 ]--- [CAUSE] After commit e1bc83f ("btrfs: get rid of compressed_folios[] usage for encoded writes"), the encoded write is changed to copy the content from the iov into a folio, and queue the folio into the compressed bio. However we always queue the full folio into the compressed bio, which can make the compressed bio larger than the on-disk extent, if the folio size is larger than the fs block size. Although we have an ASSERT() to catch such problem, for kernels without CONFIG_BTRFS_ASSERT, such larger than expected bio will just be submitted, possibly overwrite the next data extent, causing data corruption. [FIX] Instead of blindly queuing the full folio into the compressed bio, only queue the rounded up range, which is the old behavior before that offending commit. This also means we no longer need to zero the tailing range until the folio end (but still to the block boundary), as such range will not be submitted anyway. And since we're here, add a final ASSERT() into btrfs_submit_compressed_write() as the last safenet for kernels with btrfs assertions enabled Fixes: e1bc83f ("btrfs: get rid of compressed_folios[] usage for encoded writes") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com>
[BUG] When running btrfs/284, the following ASSERT() will be triggered with 64K page size and 4K fs block size: assertion failed: folio_test_writeback(folio) :: 0, in subpage.c:476 ------------[ cut here ]------------ kernel BUG at subpage.c:476! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 4 UID: 0 PID: 2313 Comm: kworker/u37:2 Tainted: G OE 6.19.0-rc8-custom+ #185 PREEMPT(voluntary) Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: btrfs-endio simple_end_io_work [btrfs] pc : btrfs_subpage_clear_writeback+0x148/0x160 [btrfs] lr : btrfs_subpage_clear_writeback+0x148/0x160 [btrfs] Call trace: btrfs_subpage_clear_writeback+0x148/0x160 [btrfs] (P) btrfs_folio_clamp_clear_writeback+0xb4/0xd0 [btrfs] end_compressed_writeback+0xe0/0x1e0 [btrfs] end_bbio_compressed_write+0x1e8/0x218 [btrfs] btrfs_bio_end_io+0x108/0x258 [btrfs] simple_end_io_work+0x68/0xa8 [btrfs] process_one_work+0x168/0x3f0 worker_thread+0x25c/0x398 kthread+0x154/0x250 ret_from_fork+0x10/0x20 ---[ end trace 0000000000000000 ]--- [CAUSE] The offending bio is from an encoded write, where the compressed data is directly written as a data extent, without touching the page cache. However the encoded write still utilizes the regular buffered write path for compressed data, by setting the compressed_bio::writeback flag. When that flag is set, at end_bbio_compressed_write() btrfs will go clearing the writeback flag of the folios in the page cache. However for bs < ps cases, the subpage helper has one extra check to make sure the folio has a writeback flag set in the first place. But since it's an encoded write, we never go through page cache, thus the folio has no writeback flag and triggers the ASSERT(). [FIX] Do not set compressed_bio::writeback flag for encoded writes, and change the ASSERT() in btrfs_submit_compressed_write() to make sure that flag is not set. Fixes: e1bc83f ("btrfs: get rid of compressed_folios[] usage for encoded writes") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com>
[BUG] When running btrfs/284 with 64K page size and 4K fs block size, it crashes with the following ASSERT() triggered: assertion failed: folio_size(fi.folio) == blocksize :: 0, in fs/btrfs/zstd.c:603 ------------[ cut here ]------------ kernel BUG at fs/btrfs/zstd.c:603! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 2 UID: 0 PID: 1183 Comm: kworker/u35:4 Not tainted 6.19.0-rc8-custom+ #185 PREEMPT(voluntary) Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: btrfs-endio simple_end_io_work [btrfs] pc : zstd_decompress_bio+0x4f0/0x508 [btrfs] lr : zstd_decompress_bio+0x4f0/0x508 [btrfs] Call trace: zstd_decompress_bio+0x4f0/0x508 [btrfs] (P) end_bbio_compressed_read+0x260/0x2c0 [btrfs] btrfs_bio_end_io+0xc4/0x258 [btrfs] btrfs_check_read_bio+0x424/0x7e0 [btrfs] simple_end_io_work+0x40/0xa8 [btrfs] process_one_work+0x168/0x3f0 worker_thread+0x25c/0x398 kthread+0x154/0x250 ret_from_fork+0x10/0x20 ---[ end trace 0000000000000000 ]--- [CAUSE] Commit 1914b94 ("btrfs: zstd: use folio_iter to handle zstd_decompress_bio()") added the ASSERT() to make sure the folio size matches the fs block size. But the check is completely wrong, the original intention is to make sure for bs > ps cases, we always got a large folio that covers a full fs block. However for bs < ps cases, a folio can never be smaller than page size, and the ASSERT() gets triggered immediately. [FIX] Check the folio size against @min_folio_size instead, which will never be smaller than PAGE_SIZE, and still cover bs > ps cases. Fixes: 1914b94 ("btrfs: zstd: use folio_iter to handle zstd_decompress_bio()") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com>
[BUG] When running btrfs/284 with 64K page size and 4K fs block size, it crashes with the following ASSERT() triggered: BTRFS info (device dm-3): use lzo compression, level 1 assertion failed: folio_size(fi.folio) == sectorsize :: 0, in lzo.c:450 ------------[ cut here ]------------ kernel BUG at lzo.c:450! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 4 UID: 0 PID: 329 Comm: kworker/u37:2 Tainted: G OE 6.19.0-rc8-custom+ #185 PREEMPT(voluntary) Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: btrfs-endio simple_end_io_work [btrfs] pc : lzo_decompress_bio+0x61c/0x630 [btrfs] lr : lzo_decompress_bio+0x61c/0x630 [btrfs] Call trace: lzo_decompress_bio+0x61c/0x630 [btrfs] (P) end_bbio_compressed_read+0x2a8/0x2c0 [btrfs] btrfs_bio_end_io+0xc4/0x258 [btrfs] btrfs_check_read_bio+0x424/0x7e0 [btrfs] simple_end_io_work+0x40/0xa8 [btrfs] process_one_work+0x168/0x3f0 worker_thread+0x25c/0x398 kthread+0x154/0x250 ret_from_fork+0x10/0x20 Code: 912a2021 b0000e00 91246000 940244e9 (d4210000) ---[ end trace 0000000000000000 ]--- [CAUSE] Commit 37cc07c ("btrfs: lzo: use folio_iter to handle lzo_decompress_bio()") added the ASSERT() to make sure the folio size matches the fs block size. But the check is completely wrong, the original intention is to make sure for bs > ps cases, we always got a large folio that covers a full fs block. However for bs < ps cases, a folio can never be smaller than page size, and the ASSERT() gets triggered immediately. [FIX] Check the folio size against @min_folio_size instead, which will never be smaller than PAGE_SIZE, and still cover bs > ps cases. Fixes: 37cc07c ("btrfs: lzo: use folio_iter to handle lzo_decompress_bio()") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com>
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