kernel/git/stable/linux.git/fs/btrfs/inode.c, branch master

Merge tag 'for-7.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2026-06-16T06:38:02+00:00

Pull btrfs updates from David Sterba: "The most noticeable change is to enable large folios by default, it's been in testing for a few releases. Related to that is huge folio support (still under experimental config). Otherwise a few ioctl updates, performance improvements and usual fixes and core changes. User visible changes: - enable large folios by default, added in 6.17 (under experimental build), no feature limitations, a big change internally - new ioctl to return raw checksums to userspace (a bit tricky given compression and tail extents), can be used for mkfs and deduplication optimizations - provide stable UUID for e.g. overlayfs and temp_fsid, also reflected in statvfs() field f_fsid, internal dev_t is hashed in to allow cloning - add 32bit compat version of GET_SUBVOL_INFO ioctl - in experimental build, support huge folios (up to 2M) Performance related improvements/changes: - limit bio size to the estimated optimum derived from the queue, this prevents build up of too much data for writeback, which could cause latency spikes (reported improvement 15% on sequential writes) - don't force direct IO to be serialized, forgotten change during mount API port, brings back +60% of throughput - lockless calculation of number of shrinkable extent maps, improve performance with many memcg allocated objects Notable fixes: - in zoned mode, fix a deadlock due to zone reclaim and relocation when space needs to be flushed - don't trim device which is internally not tracked as writeable (e.g. when missing device is being rescanned) - fix deadlock when cloning inline extent and mounted with flushoncommit - fix false IO failures after direct IO falls back to buffered write in some cases Core: - remove COW fixup mechanism completely; detect and fix changes to pages outside of filesystem tracking, guaranteed since 5.8, grace period is over - remove 2K block size support, experimental to test subpage code on x86_64 but now it would block folio changes - tree-checker improvements of: - free-space cache and tree items - root reference and backref items - extent state exceptions in reloc tree - subpage mode updates: - code optimizations, simplify tracking bitmaps - re-enable readahead of compressed extent - extend bitmap size to cover huge folios - add tracepoints related to sync, tree-log and transactions - device stats item tracking unification, remove item if there are no stats recorded, also don't leave stale stats on replaced device - allow extent buffer pages to be allocated as movable, to help page migration - added checks for proper extent buffer release - btrfs.ko code size reduction due to transaction abort call simplifications - several struct size reductions - more auto free conversions - more verbose assertions" * tag 'for-7.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (130 commits) btrfs: fix use-after-free after relocation failure with concurrent COW btrfs: move WARN_ON on unexpected error in __add_tree_block() btrfs: move locking into btrfs_get_reloc_bg_bytenr() btrfs: lzo: reject compressed segment that overflows the compressed input btrfs: retry faulting in the pages after a zero sized short direct write btrfs: fix incorrect buffered IO fallback for append direct writes btrfs: fix false IO failure after falling back to buffered write btrfs: use verbose assertions in backref.c btrfs: print a message when a missing device re-appears btrfs: do not trim a device which is not writeable btrfs: return real error after lookup failure in btrfs_ioctl_default_subvol() btrfs: use mapping shared locking for reading super block btrfs: use lockless read in nr_cached_objects shrinker callback btrfs: switch local indicator variables to bools btrfs: send: pass bool for pending_move and refs_processed parameters btrfs: use shifts for sectorsize and nodesize btrfs: fix deadlock cloning inline extent when using flushoncommit btrfs: allocate eb-attached btree pages as movable btrfs: add 32-bit compat ioctl for BTRFS_IOC_GET_SUBVOL_INFO btrfs: derive f_fsid from on-disk fsid and dev_t ...

Merge tag 'vfs-7.2-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-06-14T21:14:23+00:00

Pull vfs inode updates from Christian Brauner: "This extends the lockless ->i_count handling. iput() could already decrement any value greater than one locklessly but acquiring a reference always required taking inode->i_lock. Now acquiring a reference is lockless as long as the count was already at least 1, i.e., only the 0->1 and 1->0 transitions take the lock. This avoids the lock for the common cases of nfs calling into the inode hash and btrfs using igrab(). Cleanup-wise icount_read_once() is added to line up with inode_state_read_once() and the open-coded ->i_count loads across the tree are converted, and ihold() is relocated and tidied up. On top of that some stale lock ordering annotations are retired from the inode hash code: iunique() no longer takes the hash lock since the inode hash became RCU-searchable and s_inode_list_lock is no longer taken under the hash lock either" * tag 'vfs-7.2-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: retire stale lock ordering annotations from inode hash fs: allow lockless ->i_count bumps as long as it does not transition 0->1 fs: relocate and tidy up ihold() fs: add icount_read_once() and stop open-coding ->i_count loads

btrfs: move locking into btrfs_get_reloc_bg_bytenr()

2026-06-09T16:22:47+00:00

It does not make sense for the single caller to have the responsability to lock the relocation mutex before calling the function and then have the function to assert the lock is held. As this is a function in relocation.c, move the locking details into it. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Signed-off-by: David Sterba

btrfs: fix false IO failure after falling back to buffered write

2026-06-09T16:22:46+00:00

[BUG] The test case generic/362 will fail with "nodatasum" mount option (*): MOUNT_OPTIONS -- -o nodatasum /dev/mapper/test-scratch1 /mnt/scratch generic/362 0s ... - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad) --- tests/generic/362.out 2024-08-24 15:31:37.200000000 +0930 +++ /home/adam/xfstests/results//generic/362.out.bad 2026-05-27 10:21:17.574771567 +0930 @@ -1,2 +1,3 @@ QA output created by 362 +First write failed: Input/output error Silence is golden ... *: If the test case has been executed before with default data checksum, the failure will not reproduce. Need the following fix to make it reliably reproducible: https://lore.kernel.org/linux-btrfs/20260528111659.87113-1-wqu@suse.com/ [CAUSE] Inside __iomap_dio_rw(), the -EFAULT/-ENOTBLK error is not directly returned. Thus we never got an error pointer from __iomap_dio_rw(). The call chain looks like this: btrfs_direct_write() |- btrfs_dio_write() |- __iomap_dio_rw() | |- iomap_iter() | | |- btrfs_dio_iomap_begin() | | Now an ordered extent is allocated for the 4K write. | | | |- iomi.status = iomap_dio_iter() | | Where iomap_dio_iter() returned -EFAULT. | | | |- ret = iomap_iter() | | |- btrfs_dio_iomap_end() | | | |- btrfs_finish_ordered_extent(uptodate = false) | | | | |- can_finish_ordered_extent() | | | | |- btrfs_mark_ordered_extent_error() | | | | |- mapping_set_error() | | | | Now the address space is marked error. | | | | return -ENOTBLK | | |- return -ENOTBLK | |- if (ret == -ENOTBLK) { ret = 0; } | Now the return value is reset to 0. | Thus no error pointer will be returned. | |- ret = iomap_dio_complete() | Since no byte is submitted, @ret is 0. | |- Fallback to buffered IO | And the buffered write finished without error | |- filemap_fdatawait_range() |- filemap_check_errors() The previous error is recorded, thus an error is returned However the buffered write is properly submitted and finished, the error is from the btrfs_finish_ordered_extent() call with @uptodate = false. [FIX] When a short dio write happened, any range that is submitted will have btrfs_extract_ordered_extent() to be called, thus the submitted range will always have an OE just covering the submitted range. The remaining OE range is never submitted, thus they should be treated as truncated, not an error. So that we can properly reclaim and not insert an unnecessary file extent item, without marking the mapping as error. Extract a helper, btrfs_mark_ordered_extent_truncated(), and utilize that helper to mark the direct IO ordered extent as truncated, so it won't cause failure for the later buffered fallback. [REASON FOR NO FIXES TAG] The bug itself is pretty old, at commit f85781fb505e ("btrfs: switch to iomap for direct IO") we're already passing @uptodate=false finishing the OE. But at that time OE with IOERR won't call mapping_set_error(), so it's not exposed. Later commit d61bec08b904 ("btrfs: mark ordered extent and inode with error if we fail to finish") finally exposed the bug, but that commit is doing a correct job, not the root cause. Anyway the bug is very old, dating back to 5.1x days, thus only CC to stable. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov Signed-off-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: switch local indicator variables to bools

2026-06-09T16:22:46+00:00

For all local indicator variables do simple switch to bool, done on all files. Signed-off-by: David Sterba

btrfs: allocate eb-attached btree pages as movable

2026-06-09T16:22:45+00:00

Extent buffer pages allocated by alloc_extent_buffer() are attached to btree_inode->i_mapping (the buffer_tree path), reach the LRU, and are served by the btree_migrate_folio aops in fs/btrfs/disk-io.c. They are migratable in practice once their owning extent buffer hits refs == 1, which happens naturally. The buddy allocator classifies them by GFP, however, and bare GFP_NOFS lands them in MIGRATE_UNMOVABLE pageblocks. The result: every btree_inode page we read in pins an unmovable pageblock from the page-superblock allocator's perspective, even though the page itself can be moved. Have each caller of btrfs_alloc_page_array, btrfs_alloc_folio_array, and alloc_eb_folio_array pass in the full GFP mask directly, instead of having the functions calculate it from boolean flags. The alloc_extent_buffer call site passes GFP_NOFS | __GFP_NOFAIL | __GFP_MOVABLE. All other call sites pass plain GFP_NOFS. Three categories of caller stay on bare GFP_NOFS, deliberately: - alloc_dummy_extent_buffer / btrfs_clone_extent_buffer: the resulting eb is EXTENT_BUFFER_UNMAPPED, folio->mapping stays NULL, the folios never enter LRU, never get migrate_folio aops. Tagging them __GFP_MOVABLE would violate the page allocator's migrability contract and they would defeat compaction in MOVABLE pageblocks where isolate_migratepages_block skips non-LRU non-movable_ops pages outright. - btrfs_alloc_page_array callers in fs/btrfs/raid56.c (stripe pages), fs/btrfs/inode.c (encoded reads), fs/btrfs/ioctl.c (io_uring encoded reads), fs/btrfs/relocation.c (relocation buffers): same contract violation. raid56 stripe_pages additionally persist in the stripe cache (RBIO_CACHE_SIZE=1024) well beyond a single I/O, so they are not transient enough to hand-wave the contract. - btrfs_alloc_folio_array caller in fs/btrfs/scrub.c (stripe folios): same -- stripe->folios[] are private buffers freed via folio_put in release_scrub_stripe. This change targets the dominant fragmentation source observed on the page-superblock series: ~28 GB of btree_inode pages parked across many tainted superpageblocks on a 250 GB test system with btrfs root, preventing 1 GiB hugepage allocation from those regions. With the movable hint, those pages now land in MOVABLE pageblocks where the existing background defragger drains them through the standard PB_has_movable gate, no LRU-sample fallback needed. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Rik van Riel Signed-off-by: David Sterba

btrfs: annotate lockless read of defrag_bytes in should_nocow()

2026-06-09T16:22:44+00:00

should_nocow() reads inode->defrag_bytes without holding inode->lock, while btrfs_set_delalloc_extent() and btrfs_clear_delalloc_extent() update it under that spinlock. This is a data race. The read is a quick check used to decide whether to fall back to COW for a NOCOW inode: if defrag_bytes is non-zero and the range is tagged EXTENT_DEFRAG, we force COW so that defragmentation can rewrite the extent. Reading a stale value is harmless because: - A missed increment may skip COW once, but the defrag pass will redo the extent later. - A stale non-zero may force an unnecessary COW, which is a minor efficiency loss, not a correctness issue. On 64-bit platforms an aligned u64 load is naturally atomic so tearing cannot happen. On 32-bit platforms u64 may tear, but we only test for zero vs non-zero, so the heuristic stays correct regardless. Use data_race() annotation. Fixes: 47059d930f0e ("Btrfs: make defragment work with nodatacow option") Signed-off-by: Cen Zhang [ Use data_race() instead of READ_ONCXE() ] Signed-off-by: David Sterba

btrfs: use bvec_phys() in compressed_bio_last_folio()

2026-06-09T16:22:44+00:00

This is open-coded bvec_phys(), also remove direct use of bv_page. Reviewed-by: Qu Wenruo Reviewed-by: Boris Burkov Tested-by: Boris Burkov Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: David Sterba

btrfs: remove folio ordered flag and subpage bitmap

2026-06-08T13:53:32+00:00

Btrfs has an internal flag/subpage bitmap called ordered, which is to indicate that a block has corresponding ordered extent covering it. However this requires extra synchronization between the inode ordered tree, and the folio flag/subpage bitmap, not to mention we need to maintain the extra folio flag with subpage bitmap. As a step to align btrfs_folio_state more closely to iomap_folio_state, remove the btrfs specific ordered flag/bitmap. This will also save us 64 bytes for the bitmap of a huge folio. Since we're here, also update the ASCII graph of the bitmap, as there are only 3 sub-bitmaps now, show all sub-bitmaps directly. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: remove folio_test_ordered() usage

2026-06-08T13:53:32+00:00

This involves: - The ASSERT() inside end_bbio_data_write() It's only an ASSERT() and it has never been triggered as far as I know. - btrfs_migrate_folio() Since all folio_test_ordered() usage will be removed, there is no need to copy the folio ordered flag. - The ASSERT() inside btrfs_invalidate_folio() This one has its usefulness as it indeed caught some bugs during development. But that's the last user and will not be worth the folio flag or the subpage bitmap. This will allow btrfs to finally remove the ordered flags. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba