summaryrefslogtreecommitdiff
path: root/fs/btrfs/defrag.c
AgeCommit message (Collapse)Author
2026-06-08btrfs: move large data folios out of experimental featuresQu Wenruo
This feature was introduced in v6.17 under experimental, and we had several small bugs related to or exposed by that: e9e3b22ddfa7 ("btrfs: fix beyond-EOF write handling") 18de34daa7c6 ("btrfs: truncate ordered extent when skipping writeback past i_size") Otherwise, the feature has been frequently tested by btrfs developers. The latest fix only arrived in v6.19. After three releases, I think it's time to move this feature out of experimental. And since we're here, also remove the comment about the bitmap size limit, which is no longer relevant in the context. It will soon be outdated for the incoming huge folio support. Reviewed-by: Neal Gompa <neal@gompa.dev> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-08btrfs: remove folio checked subpage bitmap trackingQu Wenruo
The folio checked flag is only utilized by the COW fixup mechanism inside btrfs. Since the COW fixup is already removed from non-experimental builds, there is no need to keep the checked subpage bitmap. This will saves us some space for large folios, for example for a single 256K sized large folio on 4K page sized systems: Old bitmap size = 6 * (256K / 4K / 8) = 48 bytes New bitmap size = 5 * (256K / 4K / 8) = 40 bytes This will be more obvious when we're going to support huge folios (order = 9). Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
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>
2026-02-03btrfs: use the btrfs_extent_map_end() helper everywhereFilipe Manana
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: introduce BTRFS_PATH_AUTO_RELEASE() helperQu Wenruo
There are already several bugs with on-stack btrfs_path involved, even it is already a little safer than btrfs_path pointers (only leaks the extent buffers, not the btrfs_path structure itself) - Patch "btrfs: make sure extent and csum paths are always released in scrub_raid56_parity_stripe()" - Patch "btrfs: fix a potential path leak in print_data_reloc_error()" Thus there is a real need to apply auto release for those on-stack paths. Introduces a new macro, BTRFS_PATH_AUTO_RELEASE() which defines one on-stack btrfs_path structure, initialize it all to 0, then call btrfs_release_path() on it when exiting the scope. This applies to current 3 on-stack path usages: - defrag_get_extent() in defrag.c - print_data_reloc_error() in inode.c There is a special case where we want to release the path early before the time consuming iterate_extent_inodes() call, thus that manual early release is kept as is, with an extra comment added. - scrub_radi56_parity_stripe() in scrub.c Signed-off-by: Qu Wenruo <wqu@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 Torvalds
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.guards' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull superblock lock guard updates from Christian Brauner: "This starts the work of introducing guards for superblock related locks. Introduce super_write_guard for scoped superblock write protection. This provides a guard-based alternative to the manual sb_start_write() and sb_end_write() pattern, allowing the compiler to automatically handle the cleanup" * tag 'vfs-6.19-rc1.guards' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: xfs: use super write guard in xfs_file_ioctl() open: use super write guard in do_ftruncate() btrfs: use super write guard in relocating_repair_kthread() ext4: use super write guard in write_mmp_block() btrfs: use super write guard in sb_start_write() btrfs: use super write guard btrfs_run_defrag_inode() btrfs: use super write guard in btrfs_reclaim_bgs_work() fs: add super_write_guard
2025-11-24btrfs: use bool type for btrfs_path members used as booleansFilipe Manana
Many fields of struct btrfs_path are used as booleans but their type is an unsigned int (of one 1 bit width to save space). Change the type to bool keeping the :1 suffix so that they combine with the previous u8 fields in order to save space. This makes the code more clear by using explicit true/false and more in line with the preferred style, preserving the size of the structure. 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>
2025-11-24btrfs: headers cleanup to remove unnecessary local includesQu Wenruo
[BUG] When I tried to remove btrfs_bio::fs_info and use btrfs_bio::inode to grab the fs_info, the header "btrfs_inode.h" is needed to access the full btrfs_inode structure. Then btrfs will fail to compile. [CAUSE] There is a recursive including chain: "bio.h" -> "btrfs_inode.h" -> "extent_map.h" -> "compression.h" -> "bio.h" That recursive including is causing problems for btrfs. [ENHANCEMENT] To reduce the risk of recursive including: - Remove unnecessary local includes from btrfs headers Either the included header is pulled in by other headers, or is completely unnecessary. - Remove btrfs local includes if the header only requires a pointer In that case let the implementing C file to pull the required header. This is especially important for headers like "btrfs_inode.h" which pulls in a lot of other btrfs headers, thus it's a mine field of recursive including. - Remove unnecessary temporary structure definition Either if we have included the header defining the structure, or completely unused. Now including "btrfs_inode.h" inside "bio.h" is completely fine, although "btrfs_inode.h" still includes "extent_map.h", but that header only includes "fs.h", no more chain back to "bio.h". Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-05btrfs: use super write guard btrfs_run_defrag_inode()Christian Brauner
Link: https://patch.msgid.link/20251104-work-guards-v1-3-5108ac78a171@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-31btrfs: Use folio_next_pos()Matthew Wilcox (Oracle)
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>
2025-09-23btrfs: add unlikely annotations to branches leading to EIODavid Sterba
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 Sterba
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>
2025-07-22btrfs: defrag: add flag to force no-compressionDavid Sterba
Currently the defrag ioctl cannot rewrite the extents without compression. Add a new flag for that, as setting compression to 0 (or "no compression") means to do no changes to compression so take what is the current default, like mount options or properties. The defrag setting overrides mount or properties. The compression BTRFS_DEFRAG_DONT_COMPRESS is only used for in-memory operations and does not need to have a fixed value. Mount with zstd:9, copy test file from /usr/bin/ (about 260KB): $ mount -o compress=zstd:9 /dev/vda /mnt $ filefrag -vsb testfile filefrag: -b needs a blocksize option, assuming 1024-byte blocks. Filesystem type is: 9123683e File size of testfile is 297704 (292 blocks of 1024 bytes) ext: logical_offset: physical_offset: length: expected: flags: 0: 0.. 127: 13312.. 13439: 128: encoded 1: 128.. 255: 13364.. 13491: 128: 13440: encoded 2: 256.. 291: 13424.. 13459: 36: 13492: last,encoded,eof testfile: 3 extents found $ compsize testfile Processed 1 file, 3 regular extents (3 refs), 0 inline, 1 fragments. Type Perc Disk Usage Uncompressed Referenced TOTAL 42% 124K 292K 292K zstd 42% 124K 292K 292K Defrag to uncompressed: $ btrfs fi defrag --nocomp testfile $ filefrag -vsb testfile filefrag: -b needs a blocksize option, assuming 1024-byte blocks. Filesystem type is: 9123683e File size of testfile is 297704 (292 blocks of 1024 bytes) ext: logical_offset: physical_offset: length: expected: flags: 0: 0.. 291: 291840.. 292131: 292: last,eof testfile: 1 extent found $ compsize testfile Processed 1 file, 1 regular extents (1 refs), 0 inline, 1 fragments. Type Perc Disk Usage Uncompressed Referenced TOTAL 100% 292K 292K 292K none 100% 292K 292K 292K Compress again with LZO: $ btrfs fi defrag -clzo testfile $ filefrag -vsb testfile filefrag: -b needs a blocksize option, assuming 1024-byte blocks. Filesystem type is: 9123683e File size of testfile is 297704 (292 blocks of 1024 bytes) ext: logical_offset: physical_offset: length: expected: flags: 0: 0.. 127: 13312.. 13439: 128: encoded 1: 128.. 255: 13392.. 13519: 128: 13440: encoded 2: 256.. 291: 13480.. 13515: 36: 13520: last,encoded,eof testfile: 3 extents found $ compsize testfile Processed 1 file, 3 regular extents (3 refs), 0 inline, 1 fragments. Type Perc Disk Usage Uncompressed Referenced TOTAL 64% 188K 292K 292K lzo 64% 188K 292K 292K Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use folio_end() where appropriateDavid Sterba
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: rename variables for locked range in defrag_prepare_one_folio()David Sterba
In preparation to use a helper for folio_pos + folio_size, rename the variables for the locked range so they don't use the 'folio_' prefix. As the locking ranges take inclusive end of the range (hence the "-1") this would be confusing as the folio helpers typically use exclusive end of the range. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use rb_find_add() in btrfs_insert_inode_defrag()Yangtao Li
Use the rb-tree helper so we don't open code the search and insert code. Signed-off-by: Yangtao Li <frank.li@vivo.com> Signed-off-by: Pan Chuang <panchuang@vivo.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: defrag: use list_last_entry() at defrag_collect_targets()Filipe Manana
Instead of using list_entry() against the list's prev entry, use list_last_entry(), which removes the need to know the last member is accessed through the prev list pointer and the naming makes it easier to reason about what we are doing. Reviewed-by: Qu Wenruo <wqu@suse.com> 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>
2025-05-15btrfs: trivial conversion to return bool instead of intDavid Sterba
Old code has a lot of int for bool return values, bool is recommended and done in new code. Convert the trivial cases that do simple 0/false and 1/true. Functions comment are updated if needed. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: enable large data folios support for defragQu Wenruo
Currently we reject large folios for defrag gracefully, but the implementation itself is already mostly large folios compatible. There are several parts of defrag in btrfs: - Extent map checking Aka, defrag_collect_targets(), which prepares a list of target ranges that should be defragged. This part is completely folio unrelated, thus it doesn't care about the folio size. - Target folio preparation Aka, defrag_prepare_one_folio(), which lock and read (if needed) the target folio. Since folio read and lock are already supporting large folios, this part needs only minor changes. - Redirty the target range of the folio This is already done in a way supporting large folios. So it's pretty straightforward to enable large folios for defrag: - Do not reject large folios for experimental builds This affects the large folio check inside defrag_prepare_one_folio(). - Wait for ordered extents of the whole folio in defrag_prepare_one_folio() - Lock the whole extent range for all involved folios in defrag_one_range() - Allow the folios[] array to be partially empty Since we can have large folios, folios[] will not always be full. This affects: * How to allocate folios in defrag_one_range() Now we cannot use page index, but use the end position of the folio as an iterator. * How to free the folios[] array If we hit an empty slot, it means we have large folios and already hit the end of the array. * How to mark the range dirty Instead of use page index directly, we have to go through each folio, and check if the folio covers the defrag target inside defrag_one_locked_target(). Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: rename remaining exported extent map functionsFilipe Manana
Rename all the exported functions from extent_map.h that don't have a 'btrfs_' prefix in their names, so that they are consistent with all the other functions, to make it clear they are btrfs specific functions and to avoid potential name collisions in the future with functions defined elsewhere in the kernel. 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: rename functions to allocate and free extent mapsFilipe Manana
These functions are exported and don't have a 'btrfs_' prefix in their names, which goes against coding style conventions. Rename them to have such prefix, making it clear they are from btrfs and avoiding potential collisions in the future with functions defined elsewhere outside btrfs. 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: rename extent map functions to get block start, end and check if in treeFilipe Manana
These functions are exported and don't have a 'btrfs_' prefix in their names, which goes against coding style conventions. Rename them to have such prefix, making it clear they are from btrfs and avoiding potential collisions in the future with functions defined elsewhere outside btrfs. 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: rename exported extent map compression functionsFilipe Manana
These functions are exported and don't have a 'btrfs_' prefix in their names, which goes against coding style conventions. Rename them to have such prefix, making it clear they are from btrfs and avoiding potential collisions in the future with functions defined elsewhere outside btrfs. 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: rename the functions to count, test and get bit ranges in io treesFilipe Manana
These functions are exported so they should have a 'btrfs_' prefix by convention, to make it clear they are btrfs specific and to avoid collisions with functions from elsewhere in the kernel. So add a 'btrfs_' prefix to their names to make it clear they are from btrfs. 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>
2025-05-15btrfs: rename set_extent_bit() to include a btrfs prefixFilipe Manana
This is an exported function so it should have a 'btrfs_' prefix by convention, to make it clear it's btrfs specific and to avoid collisions with functions from elsewhere in the kernel. So rename it to btrfs_set_extent_bit(). 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>
2025-05-15btrfs: rename the functions to clear bits for an extent rangeFilipe Manana
These functions are exported so they should have a 'btrfs_' prefix by convention, to make it clear they are btrfs specific and to avoid collisions with functions from elsewhere in the kernel. One of them has a double underscore prefix which is also discouraged. So remove double underscore prefix where applicable and add a 'btrfs_' prefix to their name to make it clear they are from btrfs. 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>
2025-05-15btrfs: add btrfs prefix to main lock, try lock and unlock extent functionsFilipe Manana
These functions are exported so they should have a 'btrfs_' prefix by convention, to make it clear they are btrfs specific and to avoid collisions with functions from elsewhere in the kernel. So add a prefix to their name. 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>
2025-05-15btrfs: use rb_entry_safe() where possible to simplify codeDavid Sterba
Simplify conditionally reading an rb_entry(), there's the rb_entry_safe() helper that checks the node pointer for NULL so we don't have to write it explicitly. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-03-18btrfs: make btrfs_iget() return a btrfs inode insteadFilipe Manana
It's an internal function and most of the time the callers are doing a lot of BTRFS_I() calls on the returned VFS inode to get the btrfs inode, so change the return type to struct btrfs_inode instead. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-03-18btrfs: defrag: extend ioctl to accept compression levelsDaniel Vacek
The zstd and zlib compression types support setting compression levels. Enhance the defrag interface to specify the levels as well. For zstd the negative (realtime) levels are also accepted. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Daniel Vacek <neelx@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-03-18btrfs: pass struct btrfs_inode to btrfs_defrag_file()David Sterba
Pass a struct btrfs_inode to btrfs_defrag_file() as it's an internal interface, allowing to remove some use of BTRFS_I. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-10-31btrfs: fix defrag not merging contiguous extents due to merged extent mapsFilipe Manana
When running defrag (manual defrag) against a file that has extents that are contiguous and we already have the respective extent maps loaded and merged, we end up not defragging the range covered by those contiguous extents. This happens when we have an extent map that was the result of merging multiple extent maps for contiguous extents and the length of the merged extent map is greater than or equals to the defrag threshold length. The script below reproduces this scenario: $ cat test.sh #!/bin/bash DEV=/dev/sdi MNT=/mnt/sdi mkfs.btrfs -f $DEV mount $DEV $MNT # Create a 256K file with 4 extents of 64K each. xfs_io -f -c "falloc 0 64K" \ -c "pwrite 0 64K" \ -c "falloc 64K 64K" \ -c "pwrite 64K 64K" \ -c "falloc 128K 64K" \ -c "pwrite 128K 64K" \ -c "falloc 192K 64K" \ -c "pwrite 192K 64K" \ $MNT/foo umount $MNT echo -n "Initial number of file extent items: " btrfs inspect-internal dump-tree -t 5 $DEV | grep EXTENT_DATA | wc -l mount $DEV $MNT # Read the whole file in order to load and merge extent maps. cat $MNT/foo > /dev/null btrfs filesystem defragment -t 128K $MNT/foo umount $MNT echo -n "Number of file extent items after defrag with 128K threshold: " btrfs inspect-internal dump-tree -t 5 $DEV | grep EXTENT_DATA | wc -l mount $DEV $MNT # Read the whole file in order to load and merge extent maps. cat $MNT/foo > /dev/null btrfs filesystem defragment -t 256K $MNT/foo umount $MNT echo -n "Number of file extent items after defrag with 256K threshold: " btrfs inspect-internal dump-tree -t 5 $DEV | grep EXTENT_DATA | wc -l Running it: $ ./test.sh Initial number of file extent items: 4 Number of file extent items after defrag with 128K threshold: 4 Number of file extent items after defrag with 256K threshold: 4 The 4 extents don't get merged because we have an extent map with a size of 256K that is the result of merging the individual extent maps for each of the four 64K extents and at defrag_lookup_extent() we have a value of zero for the generation threshold ('newer_than' argument) since this is a manual defrag. As a consequence we don't call defrag_get_extent() to get an extent map representing a single file extent item in the inode's subvolume tree, so we end up using the merged extent map at defrag_collect_targets() and decide not to defrag. Fix this by updating defrag_lookup_extent() to always discard extent maps that were merged and call defrag_get_extent() regardless of the minimum generation threshold ('newer_than' argument). A test case for fstests will be sent along soon. CC: stable@vger.kernel.org # 6.1+ Fixes: 199257a78bb0 ("btrfs: defrag: don't use merged extent map for their generation check") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-17btrfs: fix use-after-free on rbtree that tracks inodes for auto defragFilipe Manana
When cleaning up defrag inodes at btrfs_cleanup_defrag_inodes(), called during remount and unmount, we are freeing every node from the rbtree that tracks inodes for auto defrag using rbtree_postorder_for_each_entry_safe(), which doesn't modify the tree itself. So once we unlock the lock that protects the rbtree, we have a tree pointing to a root that was freed (and a root pointing to freed nodes, and their children pointing to other freed nodes, and so on). This makes further access to the tree result in a use-after-free with unpredictable results. Fix this by initializing the rbtree to an empty root after the call to rbtree_postorder_for_each_entry_safe() and before unlocking. Fixes: 276940915f23 ("btrfs: clear defragmented inodes using postorder in btrfs_cleanup_defrag_inodes()") Reported-by: syzbot+ad7966ca1f5dd8b001b3@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/000000000000f9aad406223eabff@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>
2024-09-10btrfs: always pass readahead state to defragDavid Sterba
Defrag ioctl passes readahead from the file, but autodefrag does not have a file so the readahead state is allocated when needed. The autodefrag loop in cleaner thread iterates over inodes so we can simply provide an on-stack readahead state and will not need to allocate it in btrfs_defrag_file(). The size is 32 bytes which is acceptable. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: drop transaction parameter from btrfs_add_inode_defrag()David Sterba
There's only one caller inode_should_defrag() that passes NULL to btrfs_add_inode_defrag() so we can drop it an simplify the code. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: return void from btrfs_add_inode_defrag()David Sterba
The potential memory allocation failure is not a fatal error, skipping autodefrag is fine and the caller inode_should_defrag() does not care about the errors. Further writes can attempt to add the inode back to the defragmentation list again. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: clear defragmented inodes using postorder in ↵David Sterba
btrfs_cleanup_defrag_inodes() btrfs_cleanup_defrag_inodes() is not called frequently, only in remount or unmount, but the way it frees the inodes in fs_info->defrag_inodes is inefficient. Each time it needs to locate first node, remove it, potentially rebalance tree until it's done. This allows to do a conditional reschedule. For cleanups the rbtree_postorder_for_each_entry_safe() iterator is convenient but we can't reschedule and restart iteration because some of the tree nodes would be already freed. The cleanup operation is kmem_cache_free() which will likely take the fast path for most objects so rescheduling should not be necessary. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: rename __btrfs_run_defrag_inode() and drop double underscoresDavid Sterba
The function does not follow the pattern where the underscores would be justified, so rename it. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: rename __btrfs_add_inode_defrag() and drop double underscoresDavid Sterba
The function does not follow the pattern where the underscores would be justified, so rename it. Also update the misleading comment, the passed item is not freed, that's what the caller does. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: rename __need_auto_defrag() and drop double underscoresDavid Sterba
The function does not follow the pattern where the underscores would be justified, so rename it. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: constify arguments of compare_inode_defrag()David Sterba
A comparator function does not change its parameters, make them const. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: rename __compare_inode_defrag() and drop double underscoresDavid Sterba
The function does not follow the pattern where the underscores would be justified, so rename it. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: fix data race when accessing the last_trans field of a rootFilipe Manana
KCSAN complains about a data race when accessing the last_trans field of a root: [ 199.553628] BUG: KCSAN: data-race in btrfs_record_root_in_trans [btrfs] / record_root_in_trans [btrfs] [ 199.555186] read to 0x000000008801e308 of 8 bytes by task 2812 on cpu 1: [ 199.555210] btrfs_record_root_in_trans+0x9a/0x128 [btrfs] [ 199.555999] start_transaction+0x154/0xcd8 [btrfs] [ 199.556780] btrfs_join_transaction+0x44/0x60 [btrfs] [ 199.557559] btrfs_dirty_inode+0x9c/0x140 [btrfs] [ 199.558339] btrfs_update_time+0x8c/0xb0 [btrfs] [ 199.559123] touch_atime+0x16c/0x1e0 [ 199.559151] pipe_read+0x6a8/0x7d0 [ 199.559179] vfs_read+0x466/0x498 [ 199.559204] ksys_read+0x108/0x150 [ 199.559230] __s390x_sys_read+0x68/0x88 [ 199.559257] do_syscall+0x1c6/0x210 [ 199.559286] __do_syscall+0xc8/0xf0 [ 199.559318] system_call+0x70/0x98 [ 199.559431] write to 0x000000008801e308 of 8 bytes by task 2808 on cpu 0: [ 199.559464] record_root_in_trans+0x196/0x228 [btrfs] [ 199.560236] btrfs_record_root_in_trans+0xfe/0x128 [btrfs] [ 199.561097] start_transaction+0x154/0xcd8 [btrfs] [ 199.561927] btrfs_join_transaction+0x44/0x60 [btrfs] [ 199.562700] btrfs_dirty_inode+0x9c/0x140 [btrfs] [ 199.563493] btrfs_update_time+0x8c/0xb0 [btrfs] [ 199.564277] file_update_time+0xb8/0xf0 [ 199.564301] pipe_write+0x8ac/0xab8 [ 199.564326] vfs_write+0x33c/0x588 [ 199.564349] ksys_write+0x108/0x150 [ 199.564372] __s390x_sys_write+0x68/0x88 [ 199.564397] do_syscall+0x1c6/0x210 [ 199.564424] __do_syscall+0xc8/0xf0 [ 199.564452] system_call+0x70/0x98 This is because we update and read last_trans concurrently without any type of synchronization. This should be generally harmless and in the worst case it can make us do extra locking (btrfs_record_root_in_trans()) trigger some warnings at ctree.c or do extra work during relocation - this would probably only happen in case of load or store tearing. So fix this by always reading and updating the field using READ_ONCE() and WRITE_ONCE(), this silences KCSAN and prevents load and store tearing. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: remove super block argument from btrfs_iget()Filipe Manana
It's pointless to pass a super block argument to btrfs_iget() because we always pass a root and from it we can get the super block through: root->fs_info->sb So remove the super block argument. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.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>
2024-07-11btrfs: remove extent_map::block_start memberQu Wenruo
The member extent_map::block_start can be calculated from extent_map::disk_bytenr + extent_map::offset for regular extents. And otherwise just extent_map::disk_bytenr. And this is already validated by the validate_extent_map(). Now we can remove the member. However there is a special case in btrfs_create_dio_extent() where we for NOCOW/PREALLOC ordered extents cannot directly use the resulting btrfs_file_extent, as btrfs_split_ordered_extent() cannot handle them yet. So for that call site, we pass file_extent->disk_bytenr + file_extent->num_bytes as disk_bytenr for the ordered extent, and 0 for offset. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: remove extent_map::orig_start memberQu Wenruo
Since we have extent_map::offset, the old extent_map::orig_start is just extent_map::start - extent_map::offset for non-hole/inline extents. And since the new extent_map::offset is already verified by validate_extent_map() while the old orig_start is not, let's just remove the old member from all call sites. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: introduce new members for extent_mapQu Wenruo
Introduce two new members for extent_map: - disk_bytenr - offset Both are matching the members with the same name inside btrfs_file_extent_items. For now this patch only touches those members when: - Reading btrfs_file_extent_items from disk - Inserting new holes - Merging two extent maps With the new disk_bytenr and disk_num_bytes, doing merging would be a little more complex, as we have 3 different cases: * Both extent maps are referring to the same data extents |<----- data extent A ----->| |<- em 1 ->|<- em 2 ->| * Both extent maps are referring to different data extents |<-- data extent A -->|<-- data extent B -->| |<- em 1 ->|<- em 2 ->| * One of the extent maps is referring to a merged and larger data extent that covers both extent maps This is not really valid case other than some selftests. So this test case would be removed. A new helper merge_ondisk_extents() is introduced to handle the above valid cases. To properly assign values for those new members, a new btrfs_file_extent parameter is introduced to all the involved call sites. - For NOCOW writes the btrfs_file_extent would be exposed from can_nocow_file_extent(). - For other writes, the members can be easily calculated As most of them have 0 offset and utilizing the whole on-disk data extent. The exception is encoded write, but thankfully that interface provided offset directly and all other needed info. For now, both the old members (block_start/block_len/orig_start) are co-existing with the new members (disk_bytenr/offset), meanwhile all the critical code is still using the old members only. The cleanup will happen later after all the old and new members are properly validated. There would be some re-ordering for the assignment of the extent_map members, now we follow the new ordering: - start and len Or file_pos and num_bytes for other structures. - disk_bytenr and disk_num_bytes - offset and ram_bytes - compression So expect some seemingly unrelated line movement. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: change root->root_key.objectid to btrfs_root_id()Josef Bacik
A comment from Filipe on one of my previous cleanups brought my attention to a new helper we have for getting the root id of a root, which makes it easier to read in the code. The changes where made with the following Coccinelle semantic patch: // <smpl> @@ expression E,E1; @@ ( E->root_key.objectid = E1 | - E->root_key.objectid + btrfs_root_id(E) ) // </smpl> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor style fixups ] Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-05btrfs: remove SLAB_MEM_SPREAD flag useChengming Zhou
The SLAB_MEM_SPREAD flag used to be implemented in SLAB, which was removed as of v6.8-rc1, so it became a dead flag since the commit 16a1d968358a ("mm/slab: remove mm/slab.c and slab_def.h"). And the series[1] went on to mark it obsolete to avoid confusion for users. Here we can just remove all its users, which has no functional change. [1] https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-1-02f1753e8303@suse.cz/ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>