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

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: tag as unlikely if statements that check for fs in error state

2026-04-07T17:41:42+00:00

Having the filesystem in an error state, meaning we had a transaction abort, is unexpected. Mark every check for the error state with the unlikely annotation to convey that and to allow the compiler to generate better code. On x86_64, using gcc 14.2.0-19 from Debian, resulted in a slightly reduced object size and better code. Before: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 2008598 175912 15592 2200102 219226 fs/btrfs/btrfs.ko After: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 2008450 175912 15592 2199954 219192 fs/btrfs/btrfs.ko Reviewed-by: Anand Jain Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: introduce a common helper to calculate the size of a bio

2026-04-07T16:55:59+00:00

We have several call sites doing the same work to calculate the size of a bio: struct bio_vec *bvec; u32 bio_size = 0; int i; bio_for_each_bvec_all(bvec, bio, i) bio_size += bvec->bv_len; We can use a common helper instead of open-coding it everywhere. This also allows us to constify the @bio_size variables used in all the call sites. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge tag 'for-7.0-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2026-03-03T17:08:00+00:00

Pull btrfs fixes from David Sterba: "One-liner or short fixes for minor/moderate problems reported recently: - fixes or level adjustments of error messages - fix leaked transaction handles after aborted transactions, when using the remap tree feature - fix a few leaked chunk maps after errors - fix leaked page array in io_uring encoded read if an error occurs and the 'finished' is not called - fix double release of reserved extents when doing a range COW - don't commit super block when the filesystem is in shutdown state - fix squota accounting condition when checking members vs parent usage - other error handling fixes" * tag 'for-7.0-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: check block group lookup in remove_range_from_remap_tree() btrfs: fix transaction handle leaks in btrfs_last_identity_remap_gone() btrfs: fix chunk map leak in btrfs_map_block() after btrfs_translate_remap() btrfs: fix chunk map leak in btrfs_map_block() after btrfs_chunk_map_num_copies() btrfs: fix compat mask in error messages in btrfs_check_features() btrfs: print correct subvol num if active swapfile prevents deletion btrfs: fix warning in scrub_verify_one_metadata() btrfs: fix objectid value in error message in check_extent_data_ref() btrfs: fix incorrect key offset in error message in check_dev_extent_item() btrfs: fix error message order of parameters in btrfs_delete_delayed_dir_index() btrfs: don't commit the super block when unmounting a shutdown filesystem btrfs: free pages on error in btrfs_uring_read_extent() btrfs: fix referenced/exclusive check in squota_check_parent_usage() btrfs: remove pointless WARN_ON() in cache_save_setup() btrfs: convert log messages to error level in btrfs_replay_log() btrfs: remove btrfs_handle_fs_error() after failure to recover log trees btrfs: remove redundant warning message in btrfs_check_uuid_tree() btrfs: change warning messages to error level in open_ctree() btrfs: fix a double release on reserved extents in cow_one_range() btrfs: handle discard errors in in btrfs_finish_extent_commit()

btrfs: fix warning in scrub_verify_one_metadata()

2026-02-26T14:03:28+00:00

Commit b471965fdb2d ("btrfs: fix replace/scrub failure with metadata_uuid") 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: b471965fdb2d ("btrfs: fix replace/scrub failure with metadata_uuid") Reviewed-by: Qu Wenruo Signed-off-by: Mark Harmstone Reviewed-by: David Sterba Signed-off-by: David Sterba

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22T16:26:33+00:00

Conversion performed via this Coccinelle script: // SPDX-License-Identifier: GPL-2.0-only // Options: --include-headers-for-types --all-includes --include-headers --keep-comments virtual patch @gfp depends on patch && !(file in "tools") && !(file in "samples")@ identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex, kzalloc_obj,kzalloc_objs,kzalloc_flex, kvmalloc_obj,kvmalloc_objs,kvmalloc_flex, kvzalloc_obj,kvzalloc_objs,kvzalloc_flex}; @@ ALLOC(... - , GFP_KERNEL ) $ make coccicheck MODE=patch COCCI=gfp.cocci Build and boot tested x86_64 with Fedora 42's GCC and Clang: Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01 Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01 Signed-off-by: Kees Cook Signed-off-by: Linus Torvalds

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

btrfs: remove out label in scrub_find_fill_first_stripe()

2026-02-03T06:56:22+00:00

There is no point in having the label since all it does is return the value in the 'ret' variable. Instead make every goto return directly and remove the label. Reviewed-by: Johannes Thumshirn Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: use the btrfs_block_group_end() helper everywhere

2026-02-03T06:54:36+00:00

We have a helper to calculate a block group's exclusive end offset, but we only use it in some places. Update every site that open codes the calculation to use the helper. Reviewed-by: Johannes Thumshirn Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba