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2026-05-16btrfs: mark file extent range dirty after converting prealloc extentsRobbie Ko1-3/+8
When writing into a preallocated extent, ordered extent completion calls btrfs_mark_extent_written() to convert the file extent item from the BTRFS_FILE_EXTENT_PREALLOC type to the BTRFS_FILE_EXTENT_REG type. If the preallocated extent was created beyond i_size with fallocate keep-size, and the inode is evicted and loaded again before the write, the inode's file_extent_tree is initialized only up to i_size. The beyond i_size prealloc extent is therefore not tracked there. After a write into that extent extends i_size, btrfs_mark_extent_written() updates the file extent item, but the corresponding range is not marked dirty in the inode's file_extent_tree. This can leave disk_i_size stale when the filesystem does not use the no-holes feature, so after remount the file size can go back to the old value. The following reproducer triggers the problem: $ cat test.sh #!/bin/bash DEV=/dev/sdi MNT=/mnt/sdi mkfs.btrfs -f -O ^no-holes $DEV mount $DEV $MNT touch $MNT/file fallocate -n -l 2M $MNT/file umount $MNT mount $DEV $MNT dd if=/dev/zero of=$MNT/file bs=1M count=1 conv=notrunc ls -lh $MNT/file umount $MNT mount $DEV $MNT ls -lh $MNT/file umount $MNT Running the reproducer gives the following result: $ ./test.sh (...) 1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.000596024 s, 1.8 GB/s -rw-rw-r-- 1 root root 1.0M May 8 16:34 /mnt/sdi/file -rw-rw-r-- 1 root root 0 May 8 16:34 /mnt/sdi/file Fix this by marking the written range dirty in the inode's file_extent_tree after successfully converting the prealloc extent to a regular extent. Fixes: 9ddc959e802b ("btrfs: use the file extent tree infrastructure") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Robbie Ko <robbieko@synology.com> [ Minor change log updates ] Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-04-07btrfs: tag as unlikely if statements that check for fs in error stateFilipe Manana1-1/+1
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 <asj@kernel.org> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-04-07btrfs: pass literal booleans to functions that take boolean argumentsFilipe Manana1-2/+2
We have several functions with parameters defined as booleans but then we have callers passing integers, 0 or 1, instead of false and true. While this isn't a bug since 0 and 1 are converted to false and true, it is odd and less readable. Change the callers to pass true and false literals instead. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds1-2/+2
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook1-2/+2
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 <kees@kernel.org>
2026-02-09Merge tag 'for-6.20-tag' of ↵Linus Torvalds1-31/+29
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "User visible changes, feature updates: - when using block size > page size, enable direct IO - fallback to buffered IO if the data profile has duplication, workaround to avoid checksum mismatches on block group profiles with redundancy, real direct IO is possible on single or RAID0 - redo export of zoned statistics, moved from sysfs to /proc/pid/mountstats due to size limitations of the former Experimental features: - remove offload checksum tunable, intended to find best way to do it but since we've switched to offload to thread for everything we don't need it anymore - initial support for remap-tree feature, a translation layer of logical block addresses that allow changes without moving/rewriting blocks to do eg. relocation, or other changes that require COW Notable fixes: - automatic removal of accidentally leftover chunks when free-space-tree is enabled since mkfs.btrfs v6.16.1 - zoned mode: - do not try to append to conventional zones when RAID is mixing zoned and conventional drives - fixup write pointers when mixing zoned and conventional on DUP/RAID* profiles - when using squota, relax deletion rules for qgroups with 0 members to allow easier recovery from accounting bugs, also add more checks to detect bad accounting - fix periodic reclaim scanning, properly check boundary conditions not to trigger it unexpectedly or miss the time to run it - trim: - continue after first error - change reporting to the first detected error - add more cancellation points - reduce contention of big device lock that can block other operations when there's lots of trimmed space - when chunk allocation is forced (needs experimental build) fix transaction abort when unexpected space layout is detected Core: - switch to crypto library API for checksumming, removed module dependencies, pointer indirections, etc. - error handling improvements - adjust how and where transaction commit or abort are done and are maybe not necessary - minor compression optimization to skip single block ranges - improve how compression folios are handled - new and updated selftests - cleanups, refactoring: - auto-freeing and other automatic variable cleanup conversion - structure size optimizations - condition annotations" * tag 'for-6.20-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (137 commits) btrfs: get rid of compressed_bio::compressed_folios[] btrfs: get rid of compressed_folios[] usage for encoded writes btrfs: get rid of compressed_folios[] usage for compressed read btrfs: remove the old btrfs_compress_folios() infrastructure btrfs: switch to btrfs_compress_bio() interface for compressed writes btrfs: introduce btrfs_compress_bio() helper btrfs: zlib: introduce zlib_compress_bio() helper btrfs: zstd: introduce zstd_compress_bio() helper btrfs: lzo: introduce lzo_compress_bio() helper btrfs: zoned: factor out the zone loading part into a testable function btrfs: add cleanup function for btrfs_free_chunk_map btrfs: tests: add cleanup functions for test specific functions btrfs: raid56: fix memory leak of btrfs_raid_bio::stripe_uptodate_bitmap btrfs: tests: add unit tests for pending extent walking functions btrfs: fix EEXIST abort due to non-consecutive gaps in chunk allocation btrfs: fix transaction commit blocking during trim of unallocated space btrfs: handle user interrupt properly in btrfs_trim_fs() btrfs: preserve first error in btrfs_trim_fs() btrfs: continue trimming remaining devices on failure btrfs: do not BUG_ON() in btrfs_remove_block_group() ...
2026-02-03btrfs: remove out label in btrfs_mark_extent_written()Filipe Manana1-15/+15
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 <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-02-03btrfs: use the btrfs_extent_map_end() helper everywhereFilipe Manana1-4/+5
We have a helper to calculate an extent map'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 <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@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>
2026-02-03btrfs: move unlikely checks around btrfs_is_shutdown() into the helperFilipe Manana1-6/+6
Instead of surrounding every caller of btrfs_is_shutdown() with unlikely, move the unlikely into the helper itself, like we do in other places in btrfs and is common in the kernel outside btrfs too. Also make the fs_info argument of btrfs_is_shutdown() const. On a x86_84 box using gcc 14.2.0-19 from Debian, this resulted in a slight reduction of the module's text size. Before: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1939044 172568 15592 2127204 207564 fs/btrfs/btrfs.ko After: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1938876 172568 15592 2127036 2074bc fs/btrfs/btrfs.ko Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-02-03btrfs: merge setting ret and return retDavid Sterba1-2/+1
In many places we have pattern: ret = ...; return ret; This can be simplified to a direct return, removing 'ret' if not otherwise needed. The places in self tests are not converted so we can add more test cases without changing surrounding code (extent-map-tests.c:test_case_4()). Signed-off-by: David Sterba <dsterba@suse.com>
2026-02-03btrfs: remove dead assignment in prepare_one_folio()Massimiliano Pellizzer1-4/+2
In prepare_one_folio(), ret is initialized to 0 at declaration, and in an error path we assign ret = 0 before jumping to the again label to retry the operation. However, ret is immediately overwritten by ret = set_folio_extent_mapped(folio) after the again label. Both assignments are never observed by any code path, therefore they can be safely removed. Signed-off-by: Massimiliano Pellizzer <mpellizzer.dev@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-01-12btrfs: add setlease file operationJeff Layton1-0/+2
Add the setlease file_operation to btrfs_file_operations and btrfs_dir_file_operations, pointing to generic_setlease. A future patch will change the default behavior to reject lease attempts with -EINVAL when there is no setlease file operation defined. Add generic_setlease to retain the ability to set leases on this filesystem. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260108-setlease-6-20-v1-3-ea4dec9b67fa@kernel.org Acked-by: David Sterba <dsterba@suse.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-12-16Merge tag 'for-6.19-rc1-tag' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - fix missing btrfs_path release after printing a relocation error message - fix extent changeset leak on mmap write after failure to reserve metadata - fix fs devices list structure freeing, it could be potentially leaked under some circumstances - tree log fixes: - fix incremental directory logging where inodes for new dentries were incorrectly skipped - don't log conflicting inode if it's a directory moved in the current transaction - regression fixes: - fix incorrect btrfs_path freeing when it's auto-cleaned - revert commit simplifying preallocation of temporary structures in qgroup functions, some cases were not handled properly * tag 'for-6.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix changeset leak on mmap write after failure to reserve metadata btrfs: fix memory leak of fs_devices in degraded seed device path btrfs: fix a potential path leak in print_data_reloc_error() Revert "btrfs: add ASSERTs on prealloc in qgroup functions" btrfs: do not skip logging new dentries when logging a new name btrfs: don't log conflicting inode if it's a dir moved in the current transaction btrfs: tests: fix double btrfs_path free in remove_extent_ref()
2025-12-12btrfs: fix changeset leak on mmap write after failure to reserve metadataFilipe Manana1-1/+2
If the call to btrfs_delalloc_reserve_metadata() fails we jump to the 'out_noreserve' label and there we never free the extent_changeset allocated by the previous call to btrfs_check_data_free_space() (if qgroups are enabled). Fix this by calling extent_changeset_free() under the 'out_noreserve' label. Fixes: 6599716de2d6 ("btrfs: fix -ENOSPC mmap write failure on NOCOW files/extents") Reported-by: syzbot+2f8aa76e6acc9fce6638@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/693a635a.a70a0220.33cd7b.0029.GAE@google.com/ Reviewed-by: Qu Wenruo <wqu@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>
2025-12-03Merge tag 'for-6.19-tag' of ↵Linus Torvalds1-6/+27
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "Features: - shutdown ioctl support (needs CONFIG_BTRFS_EXPERIMENTAL for now): - set filesystem state as being shut down (also named going down in other filesystems), where all active operations return EIO and this cannot be changed until unmount - pending operations are attempted to be finished but error messages may still show up depending on where exactly the shutdown happened - scrub (and device replace) vs suspend/hibernate: - a running scrub will prevent suspend, which can be annoying as suspend is an immediate request and scrub is not critical - filesystem freezing before suspend was not sufficient as the problem was in process freezing - behaviour change: on suspend scrub and device replace are cancelled, where scrub can record the last state and continue from there; the device replace has to be restarted from the beginning - zone stats exported in sysfs, from the perspective of the filesystem this includes active, reclaimable, relocation etc zones Performance: - improvements when processing space reservation tickets by optimizing locking and shrinking critical sections, cumulative improvements in lockstat numbers show +15% Notable fixes: - use vmalloc fallback when allocating bios as high order allocations can happen with wide checksums (like sha256) - scrub will always track the last position of progress so it's not starting from zero after an error Core: - under experimental config, checksum calculations are offloaded to process context, simplifies locking and allows to remove compression write worker kthread(s): - speed improvement in direct IO throughput with buffered IO fallback is +15% when not offloaded but this is more related to internal crypto subsystem improvements - this will be probably default in the future removing the sysfs tunable - (experimental) block size > page size updates: - support more operations when not using large folios (encoded read/write and send) - raid56 - more preparations for fscrypt support Other: - more conversions to auto-cleaned variables - parameter cleanups and removals - extended warning fixes - improved printing of structured values like keys - lots of other cleanups and refactoring" * tag 'for-6.19-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (147 commits) btrfs: remove unnecessary inode key in btrfs_log_all_parents() btrfs: remove redundant zero/NULL initializations in btrfs_alloc_root() btrfs: remaining BTRFS_PATH_AUTO_FREE conversions btrfs: send: do not allocate memory for xattr data when checking it exists btrfs: send: add unlikely to all unexpected overflow checks btrfs: reduce arguments to btrfs_del_inode_ref_in_log() btrfs: remove root argument from btrfs_del_dir_entries_in_log() btrfs: use test_and_set_bit() in btrfs_delayed_delete_inode_ref() btrfs: don't search back for dir inode item in INO_LOOKUP_USER btrfs: don't rewrite ret from inode_permission btrfs: add orig_logical to btrfs_bio for encryption btrfs: disable verity on encrypted inodes btrfs: disable various operations on encrypted inodes btrfs: remove redundant level reset in btrfs_del_items() btrfs: simplify leaf traversal after path release in btrfs_next_old_leaf() btrfs: optimize balance_level() path reference handling btrfs: factor out root promotion logic into promote_child_to_root() btrfs: raid56: remove the "_step" infix btrfs: raid56: enable bs > ps support btrfs: raid56: prepare finish_parity_scrub() to support bs > ps cases ...
2025-12-01Merge tag 'vfs-6.19-rc1.folio' of ↵Linus Torvalds1-4/+5
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull folio updates from Christian Brauner: "Add a new folio_next_pos() helper function that returns the file position of the first byte after the current folio. This is a common operation in filesystems when needing to know the end of the current folio. The helper is lifted from btrfs which already had its own version, and is now used across multiple filesystems and subsystems: - btrfs - buffer - ext4 - f2fs - gfs2 - iomap - netfs - xfs - mm This fixes a long-standing bug in ocfs2 on 32-bit systems with files larger than 2GiB. Presumably this is not a common configuration, but the fix is backported anyway. The other filesystems did not have bugs, they were just mildly inefficient. This also introduce uoff_t as the unsigned version of loff_t. A recent commit inadvertently changed a comparison from being unsigned (on 64-bit systems) to being signed (which it had always been on 32-bit systems), leading to sporadic fstests failures. Generally file sizes are restricted to being a signed integer, but in places where -1 is passed to indicate "up to the end of the file", it is convenient to have an unsigned type to ensure comparisons are always unsigned regardless of architecture" * tag 'vfs-6.19-rc1.folio' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: Add uoff_t mm: Use folio_next_pos() xfs: Use folio_next_pos() netfs: Use folio_next_pos() iomap: Use folio_next_pos() gfs2: Use folio_next_pos() f2fs: Use folio_next_pos() ext4: Use folio_next_pos() buffer: Use folio_next_pos() btrfs: Use folio_next_pos() filemap: Add folio_next_pos()
2025-11-24btrfs: introduce a new shutdown stateQu Wenruo1-1/+24
A new fs state EMERGENCY_SHUTDOWN is introduced, which is btrfs' equivalent of XFS_IOC_GOINGDOWN or EXT4_IOC_SHUTDOWN, after entering emergency shutdown state, all operations will return errors (-EIO), and can not be bring back to normal state until unmouont. The new state will reject the following file operations: - read_iter() - write_iter() - mmap() - open() - remap_file_range() - uring_cmd() - splice_read() This requires a small wrapper to do the extra shutdown check, then call the regular filemap_splice_read() function This should reject most of the file operations on a shutdown btrfs. And for the existing dirty folios, extra shutdown checks are introduced to the following functions: - run_delalloc_nocow() - run_delalloc_compressed() - cow_file_range() So that dirty ranges will still be properly cleaned without being submitted. Finally the shutdown state will also set the fs error, so that no new transaction will be committed, protecting the metadata from any possible further corruption. And when the fs entered shutdown mode for the first time, a critical level kernel message will show up to indicate the incident. That message will be important for end users as rejected delalloc ranges will output error messages, hopefully that shutdown message and the fact that all fs operations are returning error will prevent end users from getting too confused about the delalloc error messages. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <asj@kernel.org> Tested-by: Anand Jain <asj@kernel.org> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-24btrfs: use end_pos variable where needed in btrfs_dirty_folio()Filipe Manana1-4/+3
We have a couple places doing the computation "pos + write_bytes" when we already have it in the local variable "end_pos". Change then to use the variable instead and make source code smaller. Also make the variable const since it's not supposed to change. This also has a very slight reduction in the module size. Before: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1915990 161647 15592 2093229 1ff0ad fs/btrfs/btrfs.ko After: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1915974 161647 15592 2093213 1ff09d fs/btrfs/btrfs.ko Reviewed-by: Qu Wenruo <wqu@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>
2025-10-31btrfs: Use folio_next_pos()Matthew Wilcox (Oracle)1-4/+5
btrfs defined its own variant of folio_next_pos() called folio_end(). This is an ambiguous name as 'end' might be exclusive or inclusive. Switch to the new folio_next_pos(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://patch.msgid.link/20251024170822.1427218-3-willy@infradead.org Acked-by: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: David Sterba <dsterba@suse.com> Cc: linux-btrfs@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-30btrfs: mark dirty extent range for out of bound prealloc extentsaustinchang1-0/+10
In btrfs_fallocate(), when the allocated range overlaps with a prealloc extent and the extent starts after i_size, the range doesn't get marked dirty in file_extent_tree. This results in persisting an incorrect disk_i_size for the inode when not using the no-holes feature. This is reproducible since commit 41a2ee75aab0 ("btrfs: introduce per-inode file extent tree"), then became hidden since commit 3d7db6e8bd22 ("btrfs: don't allocate file extent tree for non regular files") and then visible again after commit 8679d2687c35 ("btrfs: initialize inode::file_extent_tree after i_mode has been set"), which fixes the previous commit. The following reproducer triggers the problem: $ cat test.sh MNT=/mnt/test DEV=/dev/vdb mkdir -p $MNT mkfs.btrfs -f -O ^no-holes $DEV mount $DEV $MNT touch $MNT/file1 fallocate -n -o 1M -l 2M $MNT/file1 umount $MNT mount $DEV $MNT len=$((1 * 1024 * 1024)) fallocate -o 1M -l $len $MNT/file1 du --bytes $MNT/file1 umount $MNT mount $DEV $MNT du --bytes $MNT/file1 umount $MNT Running the reproducer gives the following result: $ ./test.sh (...) 2097152 /mnt/test/file1 1048576 /mnt/test/file1 The difference is exactly 1048576 as we assigned. Fix by adding a call to btrfs_inode_set_file_extent_range() in btrfs_fallocate_update_isize(). Fixes: 41a2ee75aab0 ("btrfs: introduce per-inode file extent tree") Signed-off-by: austinchang <austinchang@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-09-23btrfs: add unlikely annotations to branches leading to transaction abortDavid Sterba1-22/+21
The unlikely() annotation is a static prediction hint that compiler may use to reorder code out of hot path. We use it elsewhere (namely tree-checker.c) for error branches that almost never happen. Transaction abort is one such error, the btrfs_abort_transaction() inlines code to check the state and print a warning, this ought to be out of the hot path. The most common pattern is when transaction abort is called after checking a return value and the control flow leads to a quick return. In other cases it may not be necessary to add unlikely() e.g. when the function returns anyway or the control flow is not changed noticeably. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-09-23btrfs: add unlikely annotations to branches leading to EIODavid Sterba1-1/+1
The unlikely() annotation is a static prediction hint that compiler may use to reorder code out of hot path. We use it elsewhere (namely tree-checker.c) for error branches that almost never happen, where EIO is one of them. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-09-23btrfs: fix typos in comments and stringsDavid Sterba1-2/+2
Annual typo fixing pass. Strangely codespell found only about 30% of what is in this patch, the rest was done manually using text spellchecker with a custom dictionary of acceptable terms. Reviewed-by: Neal Gompa <neal@gompa.dev> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-28Merge tag 'vfs-6.17-rc1.mmap_prepare' of ↵Linus Torvalds1-3/+4
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull mmap_prepare updates from Christian Brauner: "Last cycle we introduce f_op->mmap_prepare() in c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback"). This is preferred to the existing f_op->mmap() hook as it does require a VMA to be established yet, thus allowing the mmap logic to invoke this hook far, far earlier, prior to inserting a VMA into the virtual address space, or performing any other heavy handed operations. This allows for much simpler unwinding on error, and for there to be a single attempt at merging a VMA rather than having to possibly reattempt a merge based on potentially altered VMA state. Far more importantly, it prevents inappropriate manipulation of incompletely initialised VMA state, which is something that has been the cause of bugs and complexity in the past. The intent is to gradually deprecate f_op->mmap, and in that vein this series coverts the majority of file systems to using f_op->mmap_prepare. Prerequisite steps are taken - firstly ensuring all checks for mmap capabilities use the file_has_valid_mmap_hooks() helper rather than directly checking for f_op->mmap (which is now not a valid check) and secondly updating daxdev_mapping_supported() to not require a VMA parameter to allow ext4 and xfs to be converted. Commit bb666b7c2707 ("mm: add mmap_prepare() compatibility layer for nested file systems") handles the nasty edge-case of nested file systems like overlayfs, which introduces a compatibility shim to allow f_op->mmap_prepare() to be invoked from an f_op->mmap() callback. This allows for nested filesystems to continue to function correctly with all file systems regardless of which callback is used. Once we finally convert all file systems, this shim can be removed. As a result, ecryptfs, fuse, and overlayfs remain unaltered so they can nest all other file systems. We additionally do not update resctl - as this requires an update to remap_pfn_range() (or an alternative to it) which we defer to a later series, equally we do not update cramfs which needs a mixed mapping insertion with the same issue, nor do we update procfs, hugetlbfs, syfs or kernfs all of which require VMAs for internal state and hooks. We shall return to all of these later" * tag 'vfs-6.17-rc1.mmap_prepare' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: doc: update porting, vfs documentation to describe mmap_prepare() fs: replace mmap hook with .mmap_prepare for simple mappings fs: convert most other generic_file_*mmap() users to .mmap_prepare() fs: convert simple use of generic_file_*_mmap() to .mmap_prepare() mm/filemap: introduce generic_file_*_mmap_prepare() helpers fs/xfs: transition from deprecated .mmap hook to .mmap_prepare fs/ext4: transition from deprecated .mmap hook to .mmap_prepare fs/dax: make it possible to check dev dax support without a VMA fs: consistently use can_mmap_file() helper mm/nommu: use file_has_valid_mmap_hooks() helper mm: rename call_mmap/mmap_prepare to vfs_mmap/mmap_prepare
2025-07-22btrfs: make btrfs_check_nocow_lock() check more than one extentFilipe Manana1-9/+30
Currently btrfs_check_nocow_lock() stops at the first extent it finds and that extent may be smaller than the target range we want to NOCOW into. But we can have multiple consecutive extents which we can NOCOW into, so by stopping at the first one we find we just make the caller do more work by splitting the write into multiple ones, or in the case of mmap writes with large folios we fail with -ENOSPC in case the folio's range is covered by more than one extent (the fallback to NOCOW for mmap writes in case there's no available data space to reserve/allocate was recently added by the patch "btrfs: fix -ENOSPC mmap write failure on NOCOW files/extents"). Improve on this by checking for multiple consecutive extents. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-22btrfs: update function comment for btrfs_check_nocow_lock()Filipe Manana1-1/+3
The documentation for the @nowait parameter is missing, so add it. The @nowait parameter was added in commit 80f9d24130e4 ("btrfs: make btrfs_check_nocow_lock nowait compatible"), which forgot to update the function comment. 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>
2025-07-22btrfs: use btrfs_inode local variable at btrfs_page_mkwrite()Filipe Manana1-34/+30
Most of the time we want to use the btrfs_inode, so change the local inode variable to be a btrfs_inode instead of a VFS inode, reducing verbosity by eliminating a lot of BTRFS_I() calls. Reviewed-by: Qu Wenruo <wqu@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>
2025-07-22btrfs: use variable for io_tree when clearing range in btrfs_page_mkwrite()Filipe Manana1-1/+1
We have the inode's io_tree already stored in a local variable, so use it instead of grabbing it again in the call to btrfs_clear_extent_bit(). Reviewed-by: Qu Wenruo <wqu@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>
2025-07-22btrfs: fix -ENOSPC mmap write failure on NOCOW files/extentsFilipe Manana1-8/+51
If we attempt a mmap write into a NOCOW file or a prealloc extent when there is no more available data space (or unallocated space to allocate a new data block group) and we can do a NOCOW write (there are no reflinks for the target extent or snapshots), we always fail due to -ENOSPC, unlike for the regular buffered write and direct IO paths where we check that we can do a NOCOW write in case we can't reserve data space. Simple reproducer: $ cat test.sh #!/bin/bash DEV=/dev/sdi MNT=/mnt/sdi umount $DEV &> /dev/null mkfs.btrfs -f -b $((512 * 1024 * 1024)) $DEV mount $DEV $MNT touch $MNT/foobar # Make it a NOCOW file. chattr +C $MNT/foobar # Add initial data to file. xfs_io -c "pwrite -S 0xab 0 1M" $MNT/foobar # Fill all the remaining data space and unallocated space with data. dd if=/dev/zero of=$MNT/filler bs=4K &> /dev/null # Overwrite the file with a mmap write. Should succeed. xfs_io -c "mmap -w 0 1M" \ -c "mwrite -S 0xcd 0 1M" \ -c "munmap" \ $MNT/foobar # Unmount, mount again and verify the new data was persisted. umount $MNT mount $DEV $MNT od -A d -t x1 $MNT/foobar umount $MNT Running this: $ ./test.sh (...) wrote 1048576/1048576 bytes at offset 0 1 MiB, 256 ops; 0.0008 sec (1.188 GiB/sec and 311435.5231 ops/sec) ./test.sh: line 24: 234865 Bus error xfs_io -c "mmap -w 0 1M" -c "mwrite -S 0xcd 0 1M" -c "munmap" $MNT/foobar 0000000 ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab * 1048576 Fix this by not failing in case we can't allocate data space and we can NOCOW into the target extent - reserving only metadata space in this case. After this change the test passes: $ ./test.sh (...) wrote 1048576/1048576 bytes at offset 0 1 MiB, 256 ops; 0.0007 sec (1.262 GiB/sec and 330749.3540 ops/sec) 0000000 cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd * 1048576 A test case for fstests will be added soon. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use pgoff_t for page index variablesDavid Sterba1-1/+1
Any conversion of offsets in the logical or the physical mapping space of the pages is done by a shift and the target type should be pgoff_t (type of struct page::index). Fix the locations where it's still unsigned long. Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use folio_next_index() helper in check_range_has_page()Qianfeng Rong1-1/+1
Simplify code pattern of 'folio->index + folio_nr_pages(folio)' by using the existing helper folio_next_index(). Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use folio_end() where appropriateDavid Sterba1-5/+4
Simplify folio_pos() + folio_size() and use the new helper. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use on-stack variable for block reserve in btrfs_replace_file_extents()David Sterba1-17/+12
We can avoid potential memory allocation failure in btrfs_replace_file_extents() as the block reserve lifetime is limited to the scope of the function. This requires +48 bytes on stack. Signed-off-by: David Sterba <dsterba@suse.com>
2025-06-19fs: replace mmap hook with .mmap_prepare for simple mappingsLorenzo Stoakes1-3/+4
Since commit c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback"), the f_op->mmap() hook has been deprecated in favour of f_op->mmap_prepare(). This callback is invoked in the mmap() logic far earlier, so error handling can be performed more safely without complicated and bug-prone state unwinding required should an error arise. This hook also avoids passing a pointer to a not-yet-correctly-established VMA avoiding any issues with referencing this data structure. It rather provides a pointer to the new struct vm_area_desc descriptor type which contains all required state and allows easy setting of required parameters without any consideration needing to be paid to locking or reference counts. Note that nested filesystems like overlayfs are compatible with an .mmap_prepare() callback since commit bb666b7c2707 ("mm: add mmap_prepare() compatibility layer for nested file systems"). In this patch we apply this change to file systems with relatively simple mmap() hook logic - exfat, ceph, f2fs, bcachefs, zonefs, btrfs, ocfs2, orangefs, nilfs2, romfs, ramfs and aio. Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Link: https://lore.kernel.org/f528ac4f35b9378931bd800920fee53fc0c5c74d.1750099179.git.lorenzo.stoakes@oracle.com Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-15btrfs: use a single variable to track return value at btrfs_page_mkwrite()Filipe Manana1-21/+16
We have two variables to track return values, ret and ret2, with types vm_fault_t (an unsigned int type) and int, which makes it a bit confusing and harder to keep track. So use a single variable, of type int, and under the 'out' label return vmf_error(ret) in case ret contains an error, otherwise return VM_FAULT_NOPAGE. This is equivalent to what we had before and it's simpler. Reviewed-by: Qu Wenruo <wqu@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>
2025-05-15btrfs: don't return VM_FAULT_SIGBUS on failure to set delalloc for mmap writeFilipe Manana1-1/+1
If the call to btrfs_set_extent_delalloc() fails we are always returning VM_FAULT_SIGBUS, which is odd since the error means "bad access" and the most likely cause for btrfs_set_extent_delalloc() is -ENOMEM, which should be translated to VM_FAULT_OOM. Instead of returning VM_FAULT_SIGBUS return vmf_error(ret2), which gives us a more appropriate return value, and we use that everywhere else too. Reviewed-by: Qu Wenruo <wqu@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>
2025-05-15btrfs: simplify early error checking in btrfs_page_mkwrite()Filipe Manana1-8/+7
We have this entangled error checks early at btrfs_page_mkwrite(): 1) Try to reserve delalloc space by calling btrfs_delalloc_reserve_space() and storing the return value in the ret2 variable; 2) If the reservation succeed, call file_update_time() and store the return value in ret2 and also set the local variable 'reserved' to true (1); 3) Then do an error check on ret2 to see if any of the previous calls failed and if so, jump either to the 'out' label or to the 'out_noreserve' label, depending on whether 'reserved' is true or not. This is unnecessarily complex. Instead change this to a simpler and more straightforward approach: 1) Call btrfs_delalloc_reserve_space(), if that returns an error jump to the 'out_noreserve' label; 2) The call file_update_time() and if that returns an error jump to the 'out' label. Like this there's less nested if statements, no need to use a local variable to track if space was reserved and if statements are used only to check errors. Also move the call to extent_changeset_free() out of the 'out_noreserve' label and under the 'out' label since the changeset is allocated only if the call to reserve delalloc space succeeded. Reviewed-by: Qu Wenruo <wqu@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>
2025-05-15btrfs: pass true to btrfs_delalloc_release_space() at btrfs_page_mkwrite()Filipe Manana1-1/+1
In the last call to btrfs_delalloc_release_space() where the value of the variable 'ret' is never zero, we pass the expression 'ret != 0' as the value for the argument 'qgroup_free', which always evaluates to true. Make this less confusing and more clear by explicitly passing true instead. Reviewed-by: Qu Wenruo <wqu@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>
2025-05-15btrfs: fix wrong start offset for delalloc space release during mmap writeFilipe Manana1-1/+1
If we're doing a mmap write against a folio that has i_size somewhere in the middle and we have multiple sectors in the folio, we may have to release excess space previously reserved, for the range going from the rounded up (to sector size) i_size to the folio's end offset. We are calculating the right amount to release and passing it to btrfs_delalloc_release_space(), but we are passing the wrong start offset of that range - we're passing the folio's start offset instead of the end offset, plus 1, of the range for which we keep the reservation. This may result in releasing more space then we should and eventually trigger an underflow of the data space_info's bytes_may_use counter. So fix this by passing the start offset as 'end + 1' instead of 'page_start' to btrfs_delalloc_release_space(). Fixes: d0b7da88f640 ("Btrfs: btrfs_page_mkwrite: Reserve space in sectorsized units") Reviewed-by: Qu Wenruo <wqu@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>
2025-05-15btrfs: simplify error return logic when getting folio at prepare_one_folio()Filipe Manana1-7/+3
There's no need to have special logic to return -EAGAIN in case the call to __filemap_get_folio() fails, because when FGP_NOWAIT is passed to __filemap_get_folio() it returns ERR_PTR(-EAGAIN) if it needs to do something that would imply blocking. The reason we have this logic is from the days before we migrated to the folio interface, when we called pagecache_get_page() which would return NULL instead of an error pointer. So remove this special casing and always return the error that the call to __filemap_get_folio() returned. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@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>
2025-05-15btrfs: handle unaligned EOF truncation correctly for subpage casesQu Wenruo1-16/+17
[BUG] The following fsx sequence will fail on btrfs with 64K page size and 4K fs block size: #fsx -d -e 1 -N 4 $mnt/junk -S 36386 READ BAD DATA: offset = 0xe9ba, size = 0x6dd5, fname = /mnt/btrfs/junk OFFSET GOOD BAD RANGE 0xe9ba 0x0000 0x03ac 0x0 operation# (mod 256) for the bad data may be 3 ... LOG DUMP (4 total operations): 1( 1 mod 256): WRITE 0x6c62 thru 0x1147d (0xa81c bytes) HOLE ***WWWW 2( 2 mod 256): TRUNCATE DOWN from 0x1147e to 0x5448 ******WWWW 3( 3 mod 256): ZERO 0x1c7aa thru 0x28fe2 (0xc839 bytes) 4( 4 mod 256): MAPREAD 0xe9ba thru 0x1578e (0x6dd5 bytes) ***RRRR*** [CAUSE] Only 2 operations are really involved in this case: 3 pollute_eof 0x5448 thru 0xffff (0xabb8 bytes) 3 zero from 0x1c7aa to 0x28fe3, (0xc839 bytes) 4 mapread 0xe9ba thru 0x1578e (0x6dd5 bytes) At operation 3, fsx pollutes beyond EOF, that is done by mmap() and write into that mmap() range beyond EOF. Such write will fill the range beyond EOF, but it will never reach disk as ranges beyond EOF will not be marked dirty nor uptodate. Then we zero_range for [0x1c7aa, 0x28fe3], and since the range is beyond our isize (which was 0x5448), we should zero out any range beyond EOF (0x5448). During btrfs_zero_range(), we call btrfs_truncate_block() to dirty the unaligned head block. But that function only really zeroes out the block at [0x5000, 0x5fff], it doesn't bother any range other that that block, since those ranges will not be marked dirty nor written back. So the range [0x6000, 0xffff] is still polluted, and later mapread() will return the poisoned value. [FIX] Enhance btrfs_truncate_block() by: - Pass a @start/@end pair to indicate the full truncation range This is to handle the following truncation case: Page size is 64K, fs block size is 4K, truncate range is [6K, 60K] 0 32K 64K | |///////////////////////////////////| | 6K 60K The range is not aligned for its head block, so we need to call btrfs_trun