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8 daysMerge tag 'ext4_for_linus-6.19-rc1' of ↵Linus Torvalds21-684/+725
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "New features and improvements for the ext4 file system: - Optimize online defragmentation by using folios instead of individual buffer heads - Improve error codes stored in the superblock when the journal aborts - Minor cleanups and clarifications in ext4_map_blocks() - Add documentation of the casefold and encrypt flags - Add support for file systems with a blocksize greater than the pagesize - Improve performance by enabling the caching the fact that an inode does not have a Posix ACL Various Bug Fixes: - Fix false positive complaints from smatch - Fix error code which is returned by ext4fs_dirhash() when Siphash is used without the encryption key - Fix races when writing to inline data files which could trigger a BUG - Fix potential NULL dereference when there is an corrupt file system with an extended attribute value stored in a inode - Fix false positive lockdep report when syzbot uses ext4 and ocfs2 together - Fix false positive reported by DEPT by adjusting lock annotation - Avoid a potential BUG_ON in jbd2 when a file system is massively corrupted - Fix a WARN_ON when superblock is corrupted with a non-NULL terminated mount options field - Add check if the userspace passes in a non-NULL terminated mount options field to EXT4_IOC_SET_TUNE_SB_PARAM - Fix a potential journal checksum failure whena file system is copied while it is mounted read-only - Fix a potential potential orphan file tracking error which only showed on 32-bit systems - Fix assertion checks in mballoc (which have to be explicitly enbled by manually enabling AGGRESSIVE_CHECKS and recompiling) - Avoid complaining about overly large orphan files created by mke2fs with with file systems with a 64k block size" * tag 'ext4_for_linus-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (58 commits) ext4: mark inodes without acls in __ext4_iget() ext4: enable block size larger than page size ext4: add checks for large folio incompatibilities when BS > PS ext4: support verifying data from large folios with fs-verity ext4: make data=journal support large block size ext4: support large block size in __ext4_block_zero_page_range() ext4: support large block size in mpage_prepare_extent_to_map() ext4: support large block size in mpage_map_and_submit_buffers() ext4: support large block size in ext4_block_write_begin() ext4: support large block size in ext4_mpage_readpages() ext4: rename 'page' references to 'folio' in multi-block allocator ext4: prepare buddy cache inode for BS > PS with large folios ext4: support large block size in ext4_mb_init_cache() ext4: support large block size in ext4_mb_get_buddy_page_lock() ext4: support large block size in ext4_mb_load_buddy_gfp() ext4: add EXT4_LBLK_TO_PG and EXT4_PG_TO_LBLK for block/page conversion ext4: add EXT4_LBLK_TO_B macro for logical block to bytes conversion ext4: support large block size in ext4_readdir() ext4: support large block size in ext4_calculate_overhead() ext4: introduce s_min_folio_order for future BS > PS support ...
10 daysMerge tag 'vfs-6.19-rc1.guards' of ↵Linus Torvalds1-6/+2
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
11 daysMerge tag 'vfs-6.19-rc1.folio' of ↵Linus Torvalds1-5/+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()
11 daysMerge tag 'vfs-6.19-rc1.writeback' of ↵Linus Torvalds1-4/+1
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull writeback updates from Christian Brauner: "Features: - Allow file systems to increase the minimum writeback chunk size. The relatively low minimal writeback size of 4MiB means that written back inodes on rotational media are switched a lot. Besides introducing additional seeks, this also can lead to extreme file fragmentation on zoned devices when a lot of files are cached relative to the available writeback bandwidth. This adds a superblock field that allows the file system to override the default size, and sets it to the zone size for zoned XFS. - Add logging for slow writeback when it exceeds sysctl_hung_task_timeout_secs. This helps identify tasks waiting for a long time and pinpoint potential issues. Recording the starting jiffies is also useful when debugging a crashed vmcore. - Wake up waiting tasks when finishing the writeback of a chunk Cleanups: - filemap_* writeback interface cleanups. Adding filemap_fdatawrite_wbc ended up being a mistake, as all but the original btrfs caller should be using better high level interfaces instead. This series removes all these low-level interfaces, switches btrfs to a more specific interface, and cleans up other too low-level interfaces. With this the writeback_control that is passed to the writeback code is only initialized in three places. - Remove __filemap_fdatawrite, __filemap_fdatawrite_range, and filemap_fdatawrite_wbc - Add filemap_flush_nr helper for btrfs - Push struct writeback_control into start_delalloc_inodes in btrfs - Rename filemap_fdatawrite_range_kick to filemap_flush_range - Stop opencoding filemap_fdatawrite_range in 9p, ocfs2, and mm - Make wbc_to_tag() inline and use it in fs" * tag 'vfs-6.19-rc1.writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: Make wbc_to_tag() inline and use it in fs. xfs: set s_min_writeback_pages for zoned file systems writeback: allow the file system to override MIN_WRITEBACK_PAGES writeback: cleanup writeback_chunk_size mm: rename filemap_fdatawrite_range_kick to filemap_flush_range mm: remove __filemap_fdatawrite_range mm: remove filemap_fdatawrite_wbc mm: remove __filemap_fdatawrite mm,btrfs: add a filemap_flush_nr helper btrfs: push struct writeback_control into start_delalloc_inodes btrfs: use the local tmp_inode variable in start_delalloc_inodes ocfs2: don't opencode filemap_fdatawrite_range in ocfs2_journal_submit_inode_data_buffers 9p: don't opencode filemap_fdatawrite_range in v9fs_mmap_vm_close mm: don't opencode filemap_fdatawrite_range in filemap_invalidate_inode writeback: Add logging for slow writeback (exceeds sysctl_hung_task_timeout_secs) writeback: Wake up waiting tasks when finishing the writeback of a chunk.
11 daysMerge tag 'vfs-6.19-rc1.inode' of ↵Linus Torvalds2-9/+8
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs inode updates from Christian Brauner: "Features: - Hide inode->i_state behind accessors. Open-coded accesses prevent asserting they are done correctly. One obvious aspect is locking, but significantly more can be checked. For example it can be detected when the code is clearing flags which are already missing, or is setting flags when it is illegal (e.g., I_FREEING when ->i_count > 0) - Provide accessors for ->i_state, converts all filesystems using coccinelle and manual conversions (btrfs, ceph, smb, f2fs, gfs2, overlayfs, nilfs2, xfs), and makes plain ->i_state access fail to compile - Rework I_NEW handling to operate without fences, simplifying the code after the accessor infrastructure is in place Cleanups: - Move wait_on_inode() from writeback.h to fs.h - Spell out fenced ->i_state accesses with explicit smp_wmb/smp_rmb for clarity - Cosmetic fixes to LRU handling - Push list presence check into inode_io_list_del() - Touch up predicts in __d_lookup_rcu() - ocfs2: retire ocfs2_drop_inode() and I_WILL_FREE usage - Assert on ->i_count in iput_final() - Assert ->i_lock held in __iget() Fixes: - Add missing fences to I_NEW handling" * tag 'vfs-6.19-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (22 commits) dcache: touch up predicts in __d_lookup_rcu() fs: push list presence check into inode_io_list_del() fs: cosmetic fixes to lru handling fs: rework I_NEW handling to operate without fences fs: make plain ->i_state access fail to compile xfs: use the new ->i_state accessors nilfs2: use the new ->i_state accessors overlayfs: use the new ->i_state accessors gfs2: use the new ->i_state accessors f2fs: use the new ->i_state accessors smb: use the new ->i_state accessors ceph: use the new ->i_state accessors btrfs: use the new ->i_state accessors Manual conversion to use ->i_state accessors of all places not covered by coccinelle Coccinelle-based conversion to use ->i_state accessors fs: provide accessors for ->i_state fs: spell out fenced ->i_state accesses with explicit smp_wmb/smp_rmb fs: move wait_on_inode() from writeback.h to fs.h fs: add missing fences to I_NEW handling ocfs2: retire ocfs2_drop_inode() and I_WILL_FREE usage ...
13 daysext4: mark inodes without acls in __ext4_iget()Jan Kara1-1/+3
Mark inodes without acls with cache_no_acl() in __ext4_iget() so that path lookup can run in RCU mode from the start. This is interesting in particular for the case where the file owner does the lookup because in that case end up constantly hitting the slow path otherwise. We drop out from the fast path (because ACL state is unknown) but never end up calling check_acl() to cache ACL state. The problem was originally analyzed by Linus and fix tested by Matheusz, I'm just putting it into mergeable form :). Link: https://lore.kernel.org/all/CAHk-=whSzc75TLLPWskV0xuaHR4tpWBr=LduqhcCFr4kCmme_w@mail.gmail.com Reported-by: Mateusz Guzik <mjguzik@gmail.com> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Message-ID: <20251125101340.24276-2-jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: enable block size larger than page sizeBaokun Li2-1/+8
Since block device (See commit 3c20917120ce ("block/bdev: enable large folio support for large logical block sizes")) and page cache (See commit ab95d23bab220ef8 ("filemap: allocate mapping_min_order folios in the page cache")) has the ability to have a minimum order when allocating folio, and ext4 has supported large folio in commit 7ac67301e82f ("ext4: enable large folio for regular file"), now add support for block_size > PAGE_SIZE in ext4. set_blocksize() -> bdev_validate_blocksize() already validates the block size, so ext4_load_super() does not need to perform additional checks. Here we only need to add the FS_LBS bit to fs_flags. In addition, block sizes larger than the page size are currently supported only when CONFIG_TRANSPARENT_HUGEPAGE is enabled. To make this explicit, a blocksize_gt_pagesize entry has been added under /sys/fs/ext4/feature/, indicating whether bs > ps is supported. This allows mke2fs to check the interface and determine whether a warning should be issued when formatting a filesystem with block size larger than the page size. Suggested-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Pankaj Raghav <p.raghav@samsung.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-25-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: add checks for large folio incompatibilities when BS > PSBaokun Li3-29/+52
Supporting a block size greater than the page size (BS > PS) requires support for large folios. However, several features (e.g., encrypt) do not yet support large folios. To prevent conflicts, this patch adds checks at mount time to prohibit these features from being used when BS > PS. Since these features cannot be changed on remount, there is no need to check on remount. This patch adds s_max_folio_order, initialized during mount according to filesystem features and mount options. If s_max_folio_order is 0, large folios are disabled. With this in place, ext4_set_inode_mapping_order() can be simplified by checking s_max_folio_order, avoiding redundant checks. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-24-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support verifying data from large folios with fs-verityBaokun Li1-2/+0
Eric Biggers already added support for verifying data from large folios several years ago in commit 5d0f0e57ed90 ("fsverity: support verifying data from large folios"). With ext4 now supporting large block sizes, the fs-verity tests `kvm-xfstests -c ext4/64k -g verity -x encrypt` pass without issues. Therefore, remove the restriction and allow large folios to be enabled together with fs-verity. Cc: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-23-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: make data=journal support large block sizeBaokun Li2-16/+20
Currently, ext4_set_inode_mapping_order() does not set max folio order for files with the data journalling flag. For files that already have large folios enabled, ext4_inode_journal_mode() ignores the data journalling flag once max folio order is set. This is not because data journalling cannot work with large folios, but because credit estimates will go through the roof if there are too many blocks per folio. Since the real constraint is blocks-per-folio, to support data=journal under LBS, we now set max folio order to be equal to min folio order for files with the journalling flag. When LBS is disabled, the max folio order remains unset as before. Therefore, before ext4_change_inode_journal_flag() switches the journalling mode, we call truncate_pagecache() to drop all page cache for that inode, and filemap_write_and_wait() is called unconditionally. After that, once the journalling mode has been switched, we can safely reset the inode mapping order, and the mapping_large_folio_support() check in ext4_inode_journal_mode() can be removed. Suggested-by: Jan Kara <jack@suse.cz> Suggested-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-22-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in __ext4_block_zero_page_range()Zhihao Cheng1-1/+1
Use the EXT4_PG_TO_LBLK() macro to convert folio indexes to blocks to avoid negative left shifts after supporting blocksize greater than PAGE_SIZE. Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-21-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in mpage_prepare_extent_to_map()Baokun Li1-4/+2
Use the EXT4_PG_TO_LBLK/EXT4_LBLK_TO_PG macros to complete the conversion between folio indexes and blocks to avoid negative left/right shifts after supporting blocksize greater than PAGE_SIZE. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-20-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in mpage_map_and_submit_buffers()Baokun Li1-4/+3
Use the EXT4_PG_TO_LBLK/EXT4_LBLK_TO_PG macros to complete the conversion between folio indexes and blocks to avoid negative left/right shifts after supporting blocksize greater than PAGE_SIZE. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-19-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in ext4_block_write_begin()Baokun Li1-4/+3
Use the EXT4_PG_TO_LBLK() macro to convert folio indexes to blocks to avoid negative left shifts after supporting blocksize greater than PAGE_SIZE. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-18-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in ext4_mpage_readpages()Baokun Li1-5/+2
Use the EXT4_PG_TO_LBLK() macro to convert folio indexes to blocks to avoid negative left shifts after supporting blocksize greater than PAGE_SIZE. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-17-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: rename 'page' references to 'folio' in multi-block allocatorZhihao Cheng1-11/+11
The ext4 multi-block allocator now fully supports folio objects. Update all variable names, function names, and comments to replace legacy 'page' terminology with 'folio', improving clarity and consistency. No functional changes. Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-16-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: prepare buddy cache inode for BS > PS with large foliosBaokun Li1-0/+2
We use EXT4_BAD_INO for the buddy cache inode number. This inode is not accessed via __ext4_new_inode() or __ext4_iget(), meaning ext4_set_inode_mapping_order() is not called to set its folio order range. However, future block size greater than page size support requires this inode to support large folios, and the buddy cache code already handles BS > PS. Therefore, ext4_set_inode_mapping_order() is now explicitly called for this specific inode to set its folio order range. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-15-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in ext4_mb_init_cache()Baokun Li1-24/+20
Currently, ext4_mb_init_cache() uses blocks_per_page to calculate the folio index and offset. However, when blocksize is larger than PAGE_SIZE, blocks_per_page becomes zero, leading to a potential division-by-zero bug. Since we now have the folio, we know its exact size. This allows us to convert {blocks, groups}_per_page to {blocks, groups}_per_folio, thus supporting block sizes greater than page size. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-14-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in ext4_mb_get_buddy_page_lock()Baokun Li1-20/+22
Currently, ext4_mb_get_buddy_page_lock() uses blocks_per_page to calculate folio index and offset. However, when blocksize is larger than PAGE_SIZE, blocks_per_page becomes zero, leading to a potential division-by-zero bug. To support BS > PS, use bytes to compute folio index and offset within folio to get rid of blocks_per_page. Also, since ext4_mb_get_buddy_page_lock() already fully supports folio, rename it to ext4_mb_get_buddy_folio_lock(). Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-13-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in ext4_mb_load_buddy_gfp()Baokun Li1-11/+16
Currently, ext4_mb_load_buddy_gfp() uses blocks_per_page to calculate the folio index and offset. However, when blocksize is larger than PAGE_SIZE, blocks_per_page becomes zero, leading to a potential division-by-zero bug. To support BS > PS, use bytes to compute folio index and offset within folio to get rid of blocks_per_page. Also, if buddy and bitmap land in the same folio, we get that folio’s ref instead of looking it up again before updating the buddy. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-12-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: add EXT4_LBLK_TO_PG and EXT4_PG_TO_LBLK for block/page conversionBaokun Li1-0/+6
As BS > PS support is coming, all block number to page index (and vice-versa) conversions must now go via bytes. Added EXT4_LBLK_TO_PG() and EXT4_PG_TO_LBLK() macros to simplify these conversions and handle both BS <= PS and BS > PS scenarios cleanly. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-11-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: add EXT4_LBLK_TO_B macro for logical block to bytes conversionBaokun Li5-18/+15
No functional changes. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-10-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in ext4_readdir()Baokun Li1-4/+4
In ext4_readdir(), page_cache_sync_readahead() is used to readahead mapped physical blocks. With LBS support, this can lead to a negative right shift. To fix this, the page index is now calculated by first converting the physical block number (pblk) to a file position (pos) before converting it to a page index. Also, the correct number of pages to readahead is now passed. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Pankaj Raghav <p.raghav@samsung.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-9-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: support large block size in ext4_calculate_overhead()Baokun Li1-3/+3
ext4_calculate_overhead() used a single page for its bitmap buffer, which worked fine when PAGE_SIZE >= block size. However, with block size greater than page size (BS > PS) support, the bitmap can exceed a single page. To address this, we now use kvmalloc() to allocate memory of the filesystem block size, to properly support BS > PS. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-8-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: introduce s_min_folio_order for future BS > PS supportBaokun Li3-6/+10
This commit introduces the s_min_folio_order field to the ext4_sb_info structure. This field will store the minimum folio order required by the current filesystem, laying groundwork for future support of block sizes greater than PAGE_SIZE. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Pankaj Raghav <p.raghav@samsung.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-7-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: enable DIOREAD_NOLOCK by default for BS > PS as wellBaokun Li1-2/+1
The dioread_nolock related processes already support large folio, so dioread_nolock is enabled by default regardless of whether the blocksize is less than, equal to, or greater than PAGE_SIZE. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-6-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: make ext4_punch_hole() support large block sizeBaokun Li1-3/+3
When preparing for bs > ps support, clean up unnecessary PAGE_SIZE references in ext4_punch_hole(). Previously, when a hole extended beyond i_size, we aligned the hole end upwards to PAGE_SIZE to handle partial folio invalidation. Now that truncate_inode_pages_range() already handles partial folio invalidation correctly, this alignment is no longer required. However, to save pointless tail block zeroing, we still keep rounding up to the block size here. In addition, as Honza pointed out, when the hole end equals i_size, it should also be rounded up to the block size. This patch fixes that as well. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-5-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: remove PAGE_SIZE checks for rec_len conversionBaokun Li1-12/+0
Previously, ext4_rec_len_(to|from)_disk only performed complex rec_len conversions when PAGE_SIZE >= 65536 to reduce complexity. However, we are soon to support file system block sizes greater than page size, which makes these conditional checks unnecessary. Thus, these checks are now removed. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-4-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: remove page offset calculation in ext4_block_truncate_page()Baokun Li1-3/+2
For bs <= ps scenarios, calculating the offset within the block is sufficient. For bs > ps, an initial page offset calculation can lead to incorrect behavior. Thus this redundant calculation has been removed. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-3-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
13 daysext4: remove page offset calculation in ext4_block_zero_page_range()Zhihao Cheng1-2/+1
For bs <= ps scenarios, calculating the offset within the block is sufficient. For bs > ps, an initial page offset calculation can lead to incorrect behavior. Thus this redundant calculation has been removed. Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-2-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26ext4: align max orphan file size with e2fsprogs limitBaokun Li1-1/+3
Kernel commit 0a6ce20c1564 ("ext4: verify orphan file size is not too big") limits the maximum supported orphan file size to 8 << 20. However, in e2fsprogs, the orphan file size is set to 32–512 filesystem blocks when creating a filesystem. With 64k block size, formatting an ext4 fs >32G gives an orphan file bigger than the kernel allows, so mount prints an error and fails: EXT4-fs (vdb): orphan file too big: 8650752 EXT4-fs (vdb): mount failed To prevent this issue and allow previously created 64KB filesystems to mount, we updates the maximum allowed orphan file size in the kernel to 512 filesystem blocks. Fixes: 0a6ce20c1564 ("ext4: verify orphan file size is not too big") Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251120134233.2994147-1-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-11-26fs/ext4: fix typo in commentHaodong Tian1-1/+1
Correct 'metdata' -> 'metadata' in comment. Signed-off-by: Haodong Tian <tianhd25@mails.tsinghua.edu.cn> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Message-ID: <20251112155916.3007639-1-tianhd25@mails.tsinghua.edu.cn> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26ext4: correct the comments place for EXT4_EXT_MAY_ZEROOUTYang Erkun1-4/+4
Move the comments just before we set EXT4_EXT_MAY_ZEROOUT in ext4_split_convert_extents. Signed-off-by: Yang Erkun <yangerkun@huawei.com> Message-ID: <20251112084538.1658232-4-yangerkun@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26ext4: cleanup for ext4_map_blocksYang Erkun1-7/+9
Retval from ext4_map_create_blocks means we really create some blocks, cannot happened with m_flags without EXT4_MAP_UNWRITTEN and EXT4_MAP_MAPPED. Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Message-ID: <20251112084538.1658232-3-yangerkun@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26ext4: rename EXT4_GET_BLOCKS_PRE_IOYang Erkun3-15/+24
This flag has been generalized to split an unwritten extent when we do dio or dioread_nolock writeback, or to avoid merge new extents which was created by extents split. Update some related comments too. Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Message-ID: <20251112084538.1658232-2-yangerkun@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26ext4: improve integrity checking in __mb_check_buddy by enhancing order-0 ↵Yongjian Sun1-17/+32
validation When the MB_CHECK_ASSERT macro is enabled, we found that the current validation logic in __mb_check_buddy has a gap in detecting certain invalid buddy states, particularly related to order-0 (bitmap) bits. The original logic consists of three steps: 1. Validates higher-order buddies: if a higher-order bit is set, at most one of the two corresponding lower-order bits may be free; if a higher-order bit is clear, both lower-order bits must be allocated (and their bitmap bits must be 0). 2. For any set bit in order-0, ensures all corresponding higher-order bits are not free. 3. Verifies that all preallocated blocks (pa) in the group have pa_pstart within bounds and their bitmap bits marked as allocated. However, this approach fails to properly validate cases where order-0 bits are incorrectly cleared (0), allowing some invalid configurations to pass: corrupt integral order 3 1 1 order 2 1 1 1 1 order 1 1 1 1 1 1 1 1 1 order 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Here we get two adjacent free blocks at order-0 with inconsistent higher-order state, and the right one shows the correct scenario. The root cause is insufficient validation of order-0 zero bits. To fix this and improve completeness without significant performance cost, we refine the logic: 1. Maintain the top-down higher-order validation, but we no longer check the cases where the higher-order bit is 0, as this case will be covered in step 2. 2. Enhance order-0 checking by examining pairs of bits: - If either bit in a pair is set (1), all corresponding higher-order bits must not be free. - If both bits are clear (0), then exactly one of the corresponding higher-order bits must be free 3. Keep the preallocation (pa) validation unchanged. This change closes the validation gap, ensuring illegal buddy states involving order-0 are correctly detected, while removing redundant checks and maintaining efficiency. Fixes: c9de560ded61f ("ext4: Add multi block allocator for ext4") Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Yongjian Sun <sunyongjian1@huawei.com> Reviewed-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251106060614.631382-3-sunyongjian@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26ext4: fix incorrect group number assertion in mb_check_buddyYongjian Sun1-0/+2
When the MB_CHECK_ASSERT macro is enabled, an assertion failure can occur in __mb_check_buddy when checking preallocated blocks (pa) in a block group: Assertion failure in mb_free_blocks() : "groupnr == e4b->bd_group" This happens when a pa at the very end of a block group (e.g., pa_pstart=32765, pa_len=3 in a group of 32768 blocks) becomes exhausted - its pa_pstart is advanced by pa_len to 32768, which lies in the next block group. If this exhausted pa (with pa_len == 0) is still in the bb_prealloc_list during the buddy check, the assertion incorrectly flags it as belonging to the wrong group. A possible sequence is as follows: ext4_mb_new_blocks ext4_mb_release_context pa->pa_pstart += EXT4_C2B(sbi, ac->ac_b_ex.fe_len) pa->pa_len -= ac->ac_b_ex.fe_len __mb_check_buddy for each pa in group ext4_get_group_no_and_offset MB_CHECK_ASSERT(groupnr == e4b->bd_group) To fix this, we modify the check to skip block group validation for exhausted preallocations (where pa_len == 0). Such entries are in a transitional state and will be removed from the list soon, so they should not trigger an assertion. This change prevents the false positive while maintaining the integrity of the checks for active allocations. Fixes: c9de560ded61f ("ext4: Add multi block allocator for ext4") Signed-off-by: Yongjian Sun <sunyongjian1@huawei.com> Reviewed-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251106060614.631382-2-sunyongjian@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-11-26ext4: add i_data_sem protection in ext4_destroy_inline_data_nolock()Alexey Nepomnyashih1-1/+6
Fix a race between inline data destruction and block mapping. The function ext4_destroy_inline_data_nolock() changes the inode data layout by clearing EXT4_INODE_INLINE_DATA and setting EXT4_INODE_EXTENTS. At the same time, another thread may execute ext4_map_blocks(), which tests EXT4_INODE_EXTENTS to decide whether to call ext4_ext_map_blocks() or ext4_ind_map_blocks(). Without i_data_sem protection, ext4_ind_map_blocks() may receive inode with EXT4_INODE_EXTENTS flag and triggering assert. kernel BUG at fs/ext4/indirect.c:546! EXT4-fs (loop2): unmounting filesystem. invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:ext4_ind_map_blocks.cold+0x2b/0x5a fs/ext4/indirect.c:546 Call Trace: <TASK> ext4_map_blocks+0xb9b/0x16f0 fs/ext4/inode.c:681 _ext4_get_block+0x242/0x590 fs/ext4/inode.c:822 ext4_block_write_begin+0x48b/0x12c0 fs/ext4/inode.c:1124 ext4_write_begin+0x598/0xef0 fs/ext4/inode.c:1255 ext4_da_write_begin+0x21e/0x9c0 fs/ext4/inode.c:3000 generic_perform_write+0x259/0x5d0 mm/filemap.c:3846 ext4_buffered_write_iter+0x15b/0x470 fs/ext4/file.c:285 ext4_file_write_iter+0x8e0/0x17f0 fs/ext4/file.c:679 call_write_iter include/linux/fs.h:2271 [inline] do_iter_readv_writev+0x212/0x3c0 fs/read_write.c:735 do_iter_write+0x186/0x710 fs/read_write.c:861 vfs_iter_write+0x70/0xa0 fs/read_write.c:902 iter_file_splice_write+0x73b/0xc90 fs/splice.c:685 do_splice_from fs/splice.c:763 [inline] direct_splice_actor+0x10f/0x170 fs/splice.c:950 splice_direct_to_actor+0x33a/0xa10 fs/splice.c:896 do_splice_direct+0x1a9/0x280 fs/splice.c:1002 do_sendfile+0xb13/0x12c0 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1323 [inline] __se_sys_sendfile64 fs/read_write.c:1309 [inline] __x64_sys_sendfile64+0x1cf/0x210 fs/read_write.c:1309 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 Fixes: c755e251357a ("ext4: fix deadlock between inline_data and ext4_expand_extra_isize_ea()") Cc: stable@vger.kernel.org # v4.11+ Signed-off-by: Alexey Nepomnyashih <sdl@nppct.ru> Message-ID: <20251104093326.697381-1-sdl@nppct.ru> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26ext4: clear i_state_flags when alloc inodeHaibo Chen3-2/+1
i_state_flags used on 32-bit archs, need to clear this flag when alloc inode. Find this issue when umount ext4, sometimes track the inode as orphan accidently, cause ext4 mesg dump. Fixes: acf943e9768e ("ext4: fix checks for orphan inodes") Signed-off-by: Haibo Chen <haibo.chen@nxp.com> Reviewed-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251104-ext4-v1-1-73691a0800f9@nxp.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-11-26ext4: check if mount_opts is NUL-terminated in ext4_ioctl_set_tune_sb()Fedor Pchelkin1-0/+4
params.mount_opts may come as potentially non-NUL-term string. Userspace is expected to pass a NUL-term string. Add an extra check to ensure this holds true. Note that further code utilizes strscpy_pad() so this is just for proper informing the user of incorrect data being provided. Found by Linux Verification Center (linuxtesting.org). Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Reviewed-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251101160430.222297-2-pchelkin@ispras.ru> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-11-26ext4: fix string copying in parse_apply_sb_mount_options()Fedor Pchelkin1-2/+3
strscpy_pad() can't be used to copy a non-NUL-term string into a NUL-term string of possibly bigger size. Commit 0efc5990bca5 ("string.h: Introduce memtostr() and memtostr_pad()") provides additional information in that regard. So if this happens, the following warning is observed: strnlen: detected buffer overflow: 65 byte read of buffer size 64 WARNING: CPU: 0 PID: 28655 at lib/string_helpers.c:1032 __fortify_report+0x96/0xc0 lib/string_helpers.c:1032 Modules linked in: CPU: 0 UID: 0 PID: 28655 Comm: syz-executor.3 Not tainted 6.12.54-syzkaller-00144-g5f0270f1ba00 #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:__fortify_report+0x96/0xc0 lib/string_helpers.c:1032 Call Trace: <TASK> __fortify_panic+0x1f/0x30 lib/string_helpers.c:1039 strnlen include/linux/fortify-string.h:235 [inline] sized_strscpy include/linux/fortify-string.h:309 [inline] parse_apply_sb_mount_options fs/ext4/super.c:2504 [inline] __ext4_fill_super fs/ext4/super.c:5261 [inline] ext4_fill_super+0x3c35/0xad00 fs/ext4/super.c:5706 get_tree_bdev_flags+0x387/0x620 fs/super.c:1636 vfs_get_tree+0x93/0x380 fs/super.c:1814 do_new_mount fs/namespace.c:3553 [inline] path_mount+0x6ae/0x1f70 fs/namespace.c:3880 do_mount fs/namespace.c:3893 [inline] __do_sys_mount fs/namespace.c:4103 [inline] __se_sys_mount fs/namespace.c:4080 [inline] __x64_sys_mount+0x280/0x300 fs/namespace.c:4080 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x64/0x140 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e Since userspace is expected to provide s_mount_opts field to be at most 63 characters long with the ending byte being NUL-term, use a 64-byte buffer which matches the size of s_mount_opts, so that strscpy_pad() does its job properly. Return with error if the user still managed to provide a non-NUL-term string here. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 8ecb790ea8c3 ("ext4: avoid potential buffer over-read in parse_apply_sb_mount_options()") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Reviewed-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251101160430.222297-1-pchelkin@ispras.ru> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-26jbd2: store more accurate errno in superblock when possibleWengang Wang1-2/+2
When jbd2_journal_abort() is called, the provided error code is stored in the journal superblock. Some existing calls hard-code -EIO even when the actual failure is not I/O related. This patch updates those calls to pass more accurate error codes, allowing the superblock to record the true cause of failure. This helps improve diagnostics and debugging clarity when analyzing journal aborts. Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Message-ID: <20251031210501.7337-1-wen.gang.wang@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-25fs: push list presence check into inode_io_list_del()Mateusz Guzik1-2/+1
For consistency with sb routines. ext4 is the only consumer outside of evict(). Damage-controlling it is outside of the scope of this cleanup. Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://patch.msgid.link/20251103230911.516866-1-mjguzik@gmail.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-13ext4: xattr: fix null pointer deref in ext4_raw_inode()Karina Yankevich1-1/+5
If ext4_get_inode_loc() fails (e.g. if it returns -EFSCORRUPTED), iloc.bh will remain set to NULL. Since ext4_xattr_inode_dec_ref_all() lacks error checking, this will lead to a null pointer dereference in ext4_raw_inode(), called right after ext4_get_inode_loc(). Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: c8e008b60492 ("ext4: ignore xattrs past end") Cc: stable@kernel.org Signed-off-by: Karina Yankevich <k.yankevich@omp.ru> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> Reviewed-by: Baokun Li <libaokun1@huawei.com> Message-ID: <20251022093253.3546296-1-k.yankevich@omp.ru> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-13ext4: refresh inline data size before write operationsDeepanshu Kartikey1-1/+6
The cached ei->i_inline_size can become stale between the initial size check and when ext4_update_inline_data()/ext4_create_inline_data() use it. Although ext4_get_max_inline_size() reads the correct value at the time of the check, concurrent xattr operations can modify i_inline_size before ext4_write_lock_xattr() is acquired. This causes ext4_update_inline_data() and ext4_create_inline_data() to work with stale capacity values, leading to a BUG_ON() crash in ext4_write_inline_data(): kernel BUG at fs/ext4/inline.c:1331! BUG_ON(pos + len > EXT4_I(inode)->i_inline_size); The race window: 1. ext4_get_max_inline_size() reads i_inline_size = 60 (correct) 2. Size check passes for 50-byte write 3. [Another thread adds xattr, i_inline_size changes to 40] 4. ext4_write_lock_xattr() acquires lock 5. ext4_update_inline_data() uses stale i_inline_size = 60 6. Attempts to write 50 bytes but only 40 bytes actually available 7. BUG_ON() triggers Fix this by recalculating i_inline_size via ext4_find_inline_data_nolock() immediately after acquiring xattr_sem. This ensures ext4_update_inline_data() and ext4_create_inline_data() work with current values that are protected from concurrent modifications. This is similar to commit a54c4613dac1 ("ext4: fix race writing to an inline_data file while its xattrs are changing") which fixed i_inline_off staleness. This patch addresses the related i_inline_size staleness issue. Reported-by: syzbot+f3185be57d7e8dda32b8@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=f3185be57d7e8dda32b8 Cc: stable@kernel.org Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com> Message-ID: <20251020060936.474314-1-kartikey406@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: add two trace points for moving extentsZhang Yi1-2/+12
To facilitate tracking the length, type, and outcome of the move extent, add a trace point at both the entry and exit of mext_move_extent(). Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-13-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: add large folios support for moving extentsZhang Yi1-17/+10
Pass the moving extent length into mext_folio_double_lock() so that it can acquire a higher-order folio if the length exceeds PAGE_SIZE. This can speed up extent moving when the extent is larger than one page. Additionally, remove the unnecessary comments from mext_folio_double_lock(). Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-12-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: switch to using the new extent movement methodZhang Yi1-344/+51
Now that we have mext_move_extent(), we can switch to this new interface and deprecate move_extent_per_page(). First, after acquiring the i_rwsem, we can directly use ext4_map_blocks() to obtain a contiguous extent from the original inode as the extent to be moved. It can and it's safe to get mapping information from the extent status tree without needing to access the ondisk extent tree, because ext4_move_extent() will check the sequence cookie under the folio lock. Then, after populating the mext_data structure, we call ext4_move_extent() to move the extent. Finally, the length of the extent will be adjusted in mext.orig_map.m_len and the actual length moved is returned through m_len. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-11-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: introduce mext_move_extent()Zhang Yi1-0/+224
When moving extents, the current move_extent_per_page() process can only move extents of length PAGE_SIZE at a time, which is highly inefficient, especially when the fragmentation of the file is not particularly severe, this will result in a large number of unnecessary extent split and merge operations. Moreover, since the ext4 file system now supports large folios, using PAGE_SIZE as the processing unit is no longer practical. Therefore, introduce a new move extents method, mext_move_extent(). It moves one extent of the origin inode at a time, but not exceeding the size of a folio. The parameters for the move are passed through the new mext_data data structure, which includes the origin inode, donor inode, the mapping extent of the origin inode to be moved, and the starting offset of the donor inode. The move process is similar to move_extent_per_page() and can be categorized into three types: MEXT_SKIP_EXTENT, MEXT_MOVE_EXTENT, and MEXT_COPY_DATA. MEXT_SKIP_EXTENT indicates that the corresponding area of the donor file is a hole, meaning no actual space is allocated, so the move is skipped. MEXT_MOVE_EXTENT indicates that the corresponding areas of both the origin and donor files are unwritten, so no data needs to be copied; only the extents are swapped. MEXT_COPY_DATA indicates that the corresponding areas of both the origin and donor files contain data, so data must be copied. The data copying is performed in three steps: first, the data from the original location is read into the page cache; then, the extents are swapped, and the page cache is rebuilt to reflect the index of the physical blocks; finally, the dirty page cache is marked and written back to ensure that the data is written to disk before the metadata is persisted. One important point to note is that the folio lock and i_data_sem are held only during the moving process. Therefore, before moving an extent, it is necessary to check whether the sequence cookie of the area to be moved has changed while holding the folio lock. If a change is detected, it indicates that concurrent write-back operations may have occurred during this period, and the type of the extent to be moved can no longer be considered reliable. For example, it may have changed from unwritten to written. In such cases, return -ESTALE, and the calling function should reacquire the move extent of the original file and retry the movement. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-10-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: rename mext_page_mkuptodate() to mext_folio_mkuptodate()Zhang Yi1-2/+2
mext_page_mkuptodate() no longer works on a single page, so rename it to mext_folio_mkuptodate(). Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-9-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: refactor mext_check_arguments()Zhang Yi1-54/+43
When moving extents, mext_check_validity() performs some basic file system and file checks. However, some essential checks need to be performed after acquiring the i_rwsem are still scattered in mext_check_arguments(). Move those checks into mext_check_validity() and make it executes entirely under the i_rwsem to make the checks clearer. Furthermore, rename mext_check_arguments() to mext_check_adjust_range(), as it only performs checks and length adjustments on the move extent range. Finally, also change the print message for the non-existent file check to be consistent with other unsupported checks. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-8-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: add mext_check_validity() to do basic checkZhang Yi2-47/+65
Currently, the basic validation checks during the move extent operation are scattered across __ext4_ioctl() and ext4_move_extents(), which makes the code somewhat disorganized. Introduce a new helper, mext_check_validity(), to handle these checks. This change involves only code relocation without any logical modifications. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-7-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: use EXT4_B_TO_LBLK() in mext_check_arguments()Zhang Yi1-6/+3
Switch to using EXT4_B_TO_LBLK() to calculate the EOF position of the origin and donor inodes, instead of using open-coded calculations. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-6-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: pass out extent seq counter when mapping blocksZhang Yi2-8/+17
When creating or querying mapping blocks using the ext4_map_blocks() and ext4_map_{query|create}_blocks() helpers, also pass out the extent sequence number of the block mapping info through the ext4_map_blocks structure. This sequence number can later serve as a valid cookie within iomap infrastructure and the move extents procedure. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-5-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: make ext4_es_lookup_extent() pass out the extent seq counterZhang Yi4-8/+10
When querying extents in the extent status tree, we should hold the data_sem if we want to obtain the sequence number as a valid cookie simultaneously. However, currently, ext4_map_blocks() calls ext4_es_lookup_extent() without holding data_sem. Therefore, we should acquire i_es_lock instead, which also ensures that the sequence cookie and the extent remain consistent. Consequently, make ext4_es_lookup_extent() to pass out the sequence number when necessary. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-4-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: introduce seq counter for the extent status entryZhang Yi3-4/+24
In the iomap_write_iter(), the iomap buffered write frame does not hold any locks between querying the inode extent mapping info and performing page cache writes. As a result, the extent mapping can be changed due to concurrent I/O in flight. Similarly, in the iomap_writepage_map(), the write-back process faces a similar problem: concurrent changes can invalidate the extent mapping before the I/O is submitted. Therefore, both of these processes must recheck the mapping info after acquiring the folio lock. To address this, similar to XFS, we propose introducing an extent sequence number to serve as a validity cookie for the extent. After commit 24b7a2331fcd ("ext4: clairfy the rules for modifying extents"), we can ensure the extent information should always be processed through the extent status tree, and the extent status tree is always uptodate under i_rwsem or invalidate_lock or folio lock, so it's safe to introduce this sequence number. The sequence number will be increased whenever the extent status tree changes, preparing for the buffered write iomap conversion. Besides, this mechanism is also applicable for the moving extents case. In move_extent_per_page(), it also needs to reacquire data_sem and check the mapping info again under the folio lock. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-3-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: correct the checking of quota files before moving extentsZhang Yi1-1/+1
The move extent operation should return -EOPNOTSUPP if any of the inodes is a quota inode, rather than requiring both to be quota inodes. Fixes: 02749a4c2082 ("ext4: add ext4_is_quota_file()") Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20251013015128.499308-2-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06fs: ext4: fix uninitialized symbolsRanganath V N2-6/+6
Fix the issue detected by the smatch tool. fs/ext4/inode.c:3583 ext4_map_blocks_atomic_write_slow() error: uninitialized symbol 'next_pblk'. fs/ext4/namei.c:1776 ext4_lookup() error: uninitialized symbol 'de'. fs/ext4/namei.c:1829 ext4_get_parent() error: uninitialized symbol 'de'. fs/ext4/namei.c:3162 ext4_rmdir() error: uninitialized symbol 'de'. fs/ext4/namei.c:3242 __ext4_unlink() error: uninitialized symbol 'de'. fs/ext4/namei.c:3697 ext4_find_delete_entry() error: uninitialized symbol 'de'. These changes enhance code clarity, address static analysis tool errors. Signed-off-by: Ranganath V N <vnranganath.20@gmail.com> Message-ID: <20251011063830.47485-1-vnranganath.20@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-06ext4: make error code in __ext4fs_dirhash() consistent.Julian Sun1-1/+1
Currently __ext4fs_dirhash() returns -1 (-EPERM) if fscrypt doesn't have encryption key, which may confuse users. Make the error code here consistent with existing error code. Signed-off-by: Julian Sun <sunjunchao@bytedance.com> Message-ID: <20251010095257.3008275-1-sunjunchao@bytedance.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-11-05ext4: use super write guard in write_mmp_block()Christian Brauner1-6/+2
Link: https://patch.msgid.link/20251104-work-guards-v1-5-5108ac78a171@kernel.org Acked-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-31ext4: Use folio_next_pos()Matthew Wilcox (Oracle)1-5/+5
This is one instruction more efficient than open-coding folio_pos() + folio_size(). It's the equivalent of (x + y) << z rather than x << z + y << z. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://patch.msgid.link/20251024170822.1427218-5-willy@infradead.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: linux-ext4@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-29fs: Make wbc_to_tag() inline and use it in fs.Julian Sun1-4/+1
The logic in wbc_to_tag() is widely used in file systems, so modify this function to be inline and use it in file systems. This patch has only passed compilation tests, but it should be fine. Signed-off-by: Julian Sun <sunjunchao@bytedance.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-20Manual conversion to use ->i_state accessors of all places not covered by ↵Mateusz Guzik2-7/+7
coccinelle Nothing to look at apart from iput_final(). Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-15Merge tag 'ext4_for_linus-6.18-rc2' of ↵Linus Torvalds3-4/+19
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 bug fixes from Ted Ts'o: - Fix regression caused by removing CONFIG_EXT3_FS when testing some very old defconfigs - Avoid a BUG_ON when opening a file on a maliciously corrupted file system - Avoid mm warnings when freeing a very large orphan file metadata - Avoid a theoretical races between metadata writeback and checkpoints (it's very hard to hit in practice, since the race requires that the writeback take a very long time) * tag 'ext4_for_linus-6.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: Use CONFIG_EXT4_FS instead of CONFIG_EXT3_FS in all of the defconfigs ext4: free orphan info with kvfree ext4: detect invalid INLINE_DATA + EXTENTS flag combination ext4, doc: fix and improve directory hash tree description ext4: wait for ongoing I/O to complete before freeing blocks jbd2: ensure that all ongoing I/O complete before freeing blocks
2025-10-10ext4: free orphan info with kvfreeJan Kara1-2/+2
Orphan info is now getting allocated with kvmalloc_array(). Free it with kvfree() instead of kfree() to avoid complaints from mm. Reported-by: Chris Mason <clm@meta.com> Fixes: 0a6ce20c1564 ("ext4: verify orphan file size is not too big") Cc: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Message-ID: <20251007134936.7291-2-jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-10-10ext4: detect invalid INLINE_DATA + EXTENTS flag combinationDeepanshu Kartikey1-0/+8
syzbot reported a BUG_ON in ext4_es_cache_extent() when opening a verity file on a corrupted ext4 filesystem mounted without a journal. The issue is that the filesystem has an inode with both the INLINE_DATA and EXTENTS flags set: EXT4-fs error (device loop0): ext4_cache_extents:545: inode #15: comm syz.0.17: corrupted extent tree: lblk 0 < prev 66 Investigation revealed that the inode has both flags set: DEBUG: inode 15 - flag=1, i_inline_off=164, has_inline=1, extents_flag=1 This is an invalid combination since an inode should have either: - INLINE_DATA: data stored directly in the inode - EXTENTS: data stored in extent-mapped blocks Having both flags causes ext4_has_inline_data() to return true, skipping extent tree validation in __ext4_iget(). The unvalidated out-of-order extents then trigger a BUG_ON in ext4_es_cache_extent() due to integer underflow when calculating hole sizes. Fix this by detecting this invalid flag combination early in ext4_iget() and rejecting the corrupted inode. Cc: stable@kernel.org Reported-and-tested-by: syzbot+038b7bf43423e132b308@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=038b7bf43423e132b308 Suggested-by: Zhang Yi <yi.zhang@huawei.com> Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Message-ID: <20250930112810.315095-1-kartikey406@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-10-10ext4: wait for ongoing I/O to complete before freeing blocksZhang Yi1-2/+9
When freeing metadata blocks in nojournal mode, ext4_forget() calls bforget() to clear the dirty flag on the buffer_head and remvoe associated mappings. This is acceptable if the metadata has not yet begun to be written back. However, if the write-back has already started but is not yet completed, ext4_forget() will have no effect. Subsequently, ext4_mb_clear_bb() will immediately return the block to the mb allocator. This block can then be reallocated immediately, potentially causing an data corruption issue. Fix this by clearing the buffer's dirty flag and waiting for the ongoing I/O to complete, ensuring that no further writes to stale data will occur. Fixes: 16e08b14a455 ("ext4: cleanup clean_bdev_aliases() calls") Cc: stable@kernel.org Reported-by: Gao Xiang <hsiangkao@linux.alibaba.com> Closes: https://lore.kernel.org/linux-ext4/a9417096-9549-4441-9878-b1955b899b4e@huaweicloud.com/ Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20250916093337.3161016-3-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-10-03Merge tag 'ext4_for_linus-6.18-rc1' of ↵Linus Torvalds14-117/+413
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "New ext4 features: - Add support so tune2fs can modify/update the superblock using an ioctl, without needing write access to the block device - Add support for 32-bit reserved uid's and gid's Bug fixes: - Fix potential warnings and other failures caused by corrupted / fuzzed file systems - Fail unaligned direct I/O write with EINVAL instead of silently falling back to buffered I/O - Correectly handle fsmap queries for metadata mappings - Avoid journal stalls caused by writeback throttling - Add some missing GFP_NOFAIL flags to avoid potential deadlocks under extremem memory pressure Cleanups: - Remove obsolete EXT3 Kconfigs" * tag 'ext4_for_linus-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix checks for orphan inodes ext4: validate ea_ino and size in check_xattrs ext4: guard against EA inode refcount underflow in xattr update ext4: implemet new ioctls to set and get superblock parameters ext4: add support for 32-bit default reserved uid and gid values ext4: avoid potential buffer over-read in parse_apply_sb_mount_options() ext4: fix an off-by-one issue during moving extents ext4: increase i_disksize to offset + len in ext4_update_disksize_before_punch() ext4: verify orphan file size is not too big ext4: fail unaligned direct IO write with EINVAL ext4: correctly handle queries for metadata mappings ext4: increase IO priority of fastcommit ext4: remove obsolete EXT3 config options jbd2: increase IO priority of checkpoint ext4: fix potential null deref in ext4_mb_init() ext4: add ext4_sb_bread_nofail() helper function for ext4_free_branches() ext4: replace min/max nesting with clamp() fs: ext4: change GFP_KERNEL to GFP_NOFS to avoid deadlock
2025-09-29Merge tag 'vfs-6.18-rc1.workqueue' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs workqueue updates from Christian Brauner: "This contains various workqueue changes affecting the filesystem layer. Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This replaces the use of system_wq and system_unbound_wq. system_wq is a per-CPU workqueue which isn't very obvious from the name and system_unbound_wq is to be used when locality is not required. So this renames system_wq to system_percpu_wq, and system_unbound_wq to system_dfl_wq. This also adds a new WQ_PERCPU flag to allow the fs subsystem users to explicitly request the use of per-CPU behavior. Both WQ_UNBOUND and WQ_PERCPU flags coexist for one release cycle to allow callers to transition their calls. WQ_UNBOUND will be removed in a next release cycle" * tag 'vfs-6.18-rc1.workqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: WQ_PERCPU added to alloc_workqueue users fs: replace use of system_wq with system_percpu_wq fs: replace use of system_unbound_wq with system_dfl_wq
2025-09-29Merge tag 'vfs-6.18-rc1.inode' of ↵Linus Torvalds5-2/+20
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs inode updates from Christian Brauner: "This contains a series I originally wrote and that Eric brought over the finish line. It moves out the i_crypt_info and i_verity_info pointers out of 'struct inode' and into the fs-specific part of the inode. So now the few filesytems that actually make use of this pay the price in their own private inode storage instead of forcing it upon every user of struct inode. The pointer for the crypt and verity info is simply found by storing an offset to its address in struct fsverity_operations and struct fscrypt_operations. This shrinks struct inode by 16 bytes. I hope to move a lot more out of it in the future so that struct inode becomes really just about very core stuff that we need, much like struct dentry and struct file, instead of the dumping ground it has become over the years. On top of this are a various changes associated with the ongoing inode lifetime handling rework that multiple people are pushing forward: - Stop accessing inode->i_count directly in f2fs and gfs2. They simply should use the __iget() and iput() helpers - Make the i_state flags an enum - Rework the iput() logic Currently, if we are the last iput, and we have the I_DIRTY_TIME bit set, we will grab a reference on the inode again and then mark it dirty and then redo the put. This is to make sure we delay the time update for as long as possible We can rework this logic to simply dec i_count if it is not 1, and if it is do the time update while still holding the i_count reference Then we can replace the atomic_dec_and_lock with locking the ->i_lock and doing atomic_dec_and_test, since we did the atomic_add_unless above - Add an icount_read() helper and convert everyone that accesses inode->i_count directly for this purpose to use the helper - Expand dump_inode() to dump more information about an inode helping in debugging - Add some might_sleep() annotations to iput() and associated helpers" * tag 'vfs-6.18-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: add might_sleep() annotation to iput() and more fs: expand dump_inode() inode: fix whitespace issues fs: add an icount_read helper fs: rework iput logic fs: make the i_state flags an enum fs: stop accessing ->i_count directly in f2fs and gfs2 fsverity: check IS_VERITY() in fsverity_cleanup_inode() fs: remove inode::i_verity_info btrfs: move verity info pointer to fs-specific part of inode f2fs: move verity info pointer to fs-specific part of inode ext4: move verity info pointer to fs-specific part of inode fsverity: add support for info in fs-specific part of inode fs: remove inode::i_crypt_info ceph: move crypt info pointer to fs-specific part of inode ubifs: move crypt info pointer to fs-specific part of inode f2fs: move crypt info pointer to fs-specific part of inode ext4: move crypt info pointer to fs-specific part of inode fscrypt: add support for info in fs-specific part of inode fscrypt: replace raw loads of info pointer with helper function
2025-09-29Merge tag 'vfs-6.18-rc1.misc' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull misc vfs updates from Christian Brauner: "This contains the usual selections of misc updates for this cycle. Features: - Add "initramfs_options" parameter to set initramfs mount options. This allows to add specific mount options to the rootfs to e.g., limit the memory size - Add RWF_NOSIGNAL flag for pwritev2() Add RWF_NOSIGNAL flag for pwritev2. This flag prevents the SIGPIPE signal from being raised when writing on disconnected pipes or sockets. The flag is handled directly by the pipe filesystem and converted to the existing MSG_NOSIGNAL flag for sockets - Allow to pass pid namespace as procfs mount option Ever since the introduction of pid namespaces, procfs has had very implicit behaviour surrounding them (the pidns used by a procfs mount is auto-selected based on the mounting process's active pidns, and the pidns itself is basically hidden once the mount has been constructed) This implicit behaviour has historically meant that userspace was required to do some special dances in order to configure the pidns of a procfs mount as desired. Examples include: * In order to bypass the mnt_too_revealing() check, Kubernetes creates a procfs mount from an empty pidns so that user namespaced containers can be nested (without this, the nested containers would fail to mount procfs) But this requires forking off a helper process because you cannot just one-shot this using mount(2) * Container runtimes in general need to fork into a container before configuring its mounts, which can lead to security issues in the case of shared-pidns containers (a privileged process in the pidns can interact with your container runtime process) While SUID_DUMP_DISABLE and user namespaces make this less of an issue, the strict need for this due to a minor uAPI wart is kind of unfortunate Things would be much easier if there was a way for userspace to just specify the pidns they want. So this pull request contains changes to implement a new "pidns" argument which can be set using fsconfig(2): fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd); fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0); or classic mount(2) / mount(8): // mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid"); Cleanups: - Remove the last references to EXPORT_OP_ASYNC_LOCK - Make file_remove_privs_flags() static - Remove redundant __GFP_NOWARN when GFP_NOWAIT is used - Use try_cmpxchg() in start_dir_add() - Use try_cmpxchg() in sb_init_done_wq() - Replace offsetof() with struct_size() in ioctl_file_dedupe_range() - Remove vfs_ioctl() export - Replace rwlock() with spinlock in epoll code as rwlock causes priority inversion on preempt rt kernels - Make ns_entries in fs/proc/namespaces const - Use a switch() statement() in init_special_inode() just like we do in may_open() - Use struct_size() in dir_add() in the initramfs code - Use str_plural() in rd_load_image() - Replace strcpy() with strscpy() in find_link() - Rename generic_delete_inode() to inode_just_drop() and generic_drop_inode() to inode_generic_drop() - Remove unused arguments from fcntl_{g,s}et_rw_hint() Fixes: - Document @name parameter for name_contains_dotdot() helper - Fix spelling mistake - Always return zero from replace_fd() instead of the file descriptor number - Limit the size for copy_file_range() in compat mode to prevent a signed overflow - Fix debugfs mount options not being applied - Verify the inode mode when loading it from disk in minixfs - Verify the inode mode when loading it from disk in cramfs - Don't trigger automounts with RESOLVE_NO_XDEV If openat2() was called with RESOLVE_NO_XDEV it didn't traverse through automounts, but could still trigger them - Add FL_RECLAIM flag to show_fl_flags() macro so it appears in tracepoints - Fix unused variable warning in rd_load_image() on s390 - Make INITRAMFS_PRESERVE_MTIME depend on BLK_DEV_INITRD - Use ns_capable_noaudit() when determining net sysctl permissions - Don't call path_put() under namespace semaphore in listmount() and statmount()" * tag 'vfs-6.18-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (38 commits) fcntl: trim arguments listmount: don't call path_put() under namespace semaphore statmount: don't call path_put() under namespace semaphore pid: use ns_capable_noaudit() when determining net sysctl permissions fs: rename generic_delete_inode() and generic_drop_inode() init: INITRAMFS_PRESERVE_MTIME should depend on BLK_DEV_INITRD initramfs: Replace strcpy() with strscpy() in find_link() initrd: Use str_plural() in rd_load_image() initramfs: Use struct_size() helper to improve dir_add() initrd: Fix unused variable warning in rd_load_image() on s390 fs: use the switch statement in init_special_inode() fs/proc/namespaces: make ns_entries const filelock: add FL_RECLAIM to show_fl_flags() macro eventpoll: Replace rwlock with spinlock selftests/proc: add tests for new pidns APIs procfs: add "pidns" mount option pidns: move is-ancestor logic to helper openat2: don't trigger automounts with RESOLVE_NO_XDEV namei: move cross-device check to __traverse_mounts namei: remove LOOKUP_NO_XDEV check from handle_mounts ...
2025-09-26ext4: fix checks for orphan inodesJan Kara5-9/+15
When orphan file feature is enabled, inode can be tracked as orphan either in the standard orphan list or in the orphan file. The first can be tested by checking ei->i_orphan list head, the second is recorded by EXT4_STATE_ORPHAN_FILE inode state flag. There are several places where we want to check whether inode is tracked as orphan and only some of them properly check for both possibilities. Luckily the consequences are mostly minor, the worst that can happen is that we track an inode as orphan although we don't need to and e2fsck then complains (resulting in occasional ext4/307 xfstest failures). Fix the problem by introducing a helper for checking whether an inode is tracked as orphan and use it in appropriate places. Fixes: 4a79a98c7b19 ("ext4: Improve scalability of ext4 orphan file handling") Cc: stable@kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Message-ID: <20250925123038.20264-2-jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: validate ea_ino and size in check_xattrsDeepanshu Kartikey1-0/+4
During xattr block validation, check_xattrs() processes xattr entries without validating that entries claiming to use EA inodes have non-zero sizes. Corrupted filesystems may contain xattr entries where e_value_size is zero but e_value_inum is non-zero, indicating invalid xattr data. Add validation in check_xattrs() to detect this corruption pattern early and return -EFSCORRUPTED, preventing invalid xattr entries from causing issues throughout the ext4 codebase. Cc: stable@kernel.org Suggested-by: Theodore Ts'o <tytso@mit.edu> Reported-by: syzbot+4c9d23743a2409b80293@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=4c9d23743a2409b80293 Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Message-ID: <20250923133245.1091761-1-kartikey406@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: guard against EA inode refcount underflow in xattr updateAhmet Eray Karadag1-7/+8
syzkaller found a path where ext4_xattr_inode_update_ref() reads an EA inode refcount that is already <= 0 and then applies ref_change (often -1). That lets the refcount underflow and we proceed with a bogus value, triggering errors like: EXT4-fs error: EA inode <n> ref underflow: ref_count=-1 ref_change=-1 EXT4-fs warning: ea_inode dec ref err=-117 Make the invariant explicit: if the current refcount is non-positive, treat this as on-disk corruption, emit ext4_error_inode(), and fail the operation with -EFSCORRUPTED instead of updating the refcount. Delete the WARN_ONCE() as negative refcounts are now impossible; keep error reporting in ext4_error_inode(). This prevents the underflow and the follow-on orphan/cleanup churn. Reported-by: syzbot+0be4f339a8218d2a5bb1@syzkaller.appspotmail.com Fixes: https://syzbot.org/bug?extid=0be4f339a8218d2a5bb1 Cc: stable@kernel.org Co-developed-by: Albin Babu Varghese <albinbabuvarghese20@gmail.com> Signed-off-by: Albin Babu Varghese <albinbabuvarghese20@gmail.com> Signed-off-by: Ahmet Eray Karadag <eraykrdg1@gmail.com> Message-ID: <20250920021342.45575-1-eraykrdg1@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: implemet new ioctls to set and get superblock parametersTheodore Ts'o1-7/+305
Implement the EXT4_IOC_GET_TUNE_SB_PARAM and EXT4_IOC_SET_TUNE_SB_PARAM ioctls, which allow certains superblock parameters to be set while the file system is mounted, without needing write access to the block device. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Message-ID: <20250916-tune2fs-v2-3-d594dc7486f0@mit.edu> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: add support for 32-bit default reserved uid and gid valuesTheodore Ts'o2-5/+19
Support for specifying the default user id and group id that is allowed to use the reserved block space was added way back when Linux only supported 16-bit uid's and gid's. (Yeah, that long ago.) It's not a commonly used feature, but let's add support for 32-bit user and group id's. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Message-ID: <20250916-tune2fs-v2-2-d594dc7486f0@mit.edu> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: avoid potential buffer over-read in parse_apply_sb_mount_options()Theodore Ts'o1-12/+5
Unlike other strings in the ext4 superblock, we rely on tune2fs to make sure s_mount_opts is NUL terminated. Harden parse_apply_sb_mount_options() by treating s_mount_opts as a potential __nonstring. Cc: stable@vger.kernel.org Fixes: 8b67f04ab9de ("ext4: Add mount options in superblock") Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Message-ID: <20250916-tune2fs-v2-1-d594dc7486f0@mit.edu> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: fix an off-by-one issue during moving extentsZhang Yi1-1/+1
During the movement of a written extent, mext_page_mkuptodate() is called to read data in the range [from, to) into the page cache and to update the corresponding buffers. Therefore, we should not wait on any buffer whose start offset is >= 'to'. Otherwise, it will return -EIO and fail the extents movement. $ for i in `seq 3 -1 0`; \ do xfs_io -fs -c "pwrite -b 1024 $((i * 1024)) 1024" /mnt/foo; \ done $ umount /mnt && mount /dev/pmem1s /mnt # drop cache $ e4defrag /mnt/foo e4defrag 1.47.0 (5-Feb-2023) ext4 defragmentation for /mnt/foo [1/1]/mnt/foo: 0% [ NG ] Success: [0/1] Cc: stable@kernel.org Fixes: a40759fb16ae ("ext4: remove array of buffer_heads from mext_page_mkuptodate()") Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20250912105841.1886799-1-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: increase i_disksize to offset + len in ext4_update_disksize_before_punch()Yongjian Sun1-2/+8
After running a stress test combined with fault injection, we performed fsck -a followed by fsck -fn on the filesystem image. During the second pass, fsck -fn reported: Inode 131512, end of extent exceeds allowed value (logical block 405, physical block 1180540, len 2) This inode was not in the orphan list. Analysis revealed the following call chain that leads to the inconsistency: ext4_da_write_end() //does not update i_disksize ext4_punch_hole() //truncate folio, keep size ext4_page_mkwrite() ext4_block_page_mkwrite() ext4_block_write_begin() ext4_get_block() //insert written extent without update i_disksize journal commit echo 1 > /sys/block/xxx/device/delete da-write path updates i_size but does not update i_disksize. Then ext4_punch_hole truncates the da-folio yet still leaves i_disksize unchanged(in the ext4_update_disksize_before_punch function, the condition offset + len < size is met). Then ext4_page_mkwrite sees ext4_nonda_switch return 1 and takes the nodioread_nolock path, the folio about to be written has just been punched out, and it’s offset sits beyond the current i_disksize. This may result in a written extent being inserted, but again does not update i_disksize. If the journal gets committed and then the block device is yanked, we might run into this. It should be noted that replacing ext4_punch_hole with ext4_zero_range in the call sequence may also trigger this issue, as neither will update i_disksize under these circumstances. To fix this, we can modify ext4_update_disksize_before_punch to increase i_disksize to min(i_size, offset + len) when both i_size and (offset + len) are greater than i_disksize. Cc: stable@kernel.org Signed-off-by: Yongjian Sun <sunyongjian1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Message-ID: <20250911133024.1841027-1-sunyongjian@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: verify orphan file size is not too bigJan Kara1-1/+12
In principle orphan file can be arbitrarily large. However orphan replay needs to traverse it all and we also pin all its buffers in memory. Thus filesystems with absurdly large orphan files can lead to big amounts of memory consumed. Limit orphan file size to a sane value and also use kvmalloc() for allocating array of block descriptor structures to avoid large order allocations for sane but large orphan files. Reported-by: syzbot+0b92850d68d9b12934f5@syzkaller.appspotmail.com Fixes: 02f310fcf47f ("ext4: Speedup ext4 orphan inode handling") Cc: stable@kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Message-ID: <20250909112206.10459-2-jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-26ext4: fail unaligned direct IO write with EINVALJan Kara1-35/+0
Commit bc264fea0f6f ("iomap: support incremental iomap_iter advances") changed the error handling logic in iomap_iter(). Previously any error from iomap_dio_bio_iter() got propagated to userspace, after this commit if ->iomap_end returns error, it gets propagated to userspace instead of an error from iomap_dio_bio_iter(). This results in unaligned writes to ext4 to silently fallback to buffered IO instead of erroring out. Now returning ENOTBLK for DIO writes from ext4_iomap_end() seems unnecessary these days. It is enough to return ENOTBLK from ext4_iomap_begin() when we don't support DIO write for that particular file offset (due to hole). Fixes: bc264fea0f6f ("iomap: support incremental iomap_iter advances") Cc: stable@kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Message-ID: <20250901112739.32484-2-jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-25ext4: correctly handle queries for metadata mappingsOjaswin Mujoo1-5/+9
Currently, our handling of metadata is _ambiguous_ in some scenarios, that is, we end up returning unknown if the range only covers the mapping partially. For example, in the following case: $ xfs_io -c fsmap -d 0: 254:16 [0..7]: static fs metadata 8 1: 254:16 [8..15]: special 102:1 8 2: 254:16 [16..5127]: special 102:2 5112 3: 254:16 [5128..5255]: special 102:3 128 4: 254:16 [5256..5383]: special 102:4 128 5: 254:16 [5384..70919]: inodes 65536 6: 254:16 [70920..70967]: unknown 48 ... $ xfs_io -c fsmap -d 24 33 0: 254:16 [24..39]: unknown 16 <--- incomplete reporting $ xfs_io -c fsmap -d 24 33 (With patch) 0: 254:16 [16..5127]: special 102:2 5112 This is because earlier in ext4_getfsmap_meta_helper, we end up ignoring any extent that starts before our queried range, but overlaps it. While the man page [1] is a bit ambiguous on this, this fix makes the output make more sense since we are anyways returning an "unknown" extent. This is also consistent to how XFS does it: $ xfs_io -c fsmap -d ... 6: 254:16 [104..127]: free space 24 7: 254:16 [128..191]: inodes 64 ... $ xfs_io -c fsmap -d 137 150 0: 254:16 [128..191]: inodes 64 <-- full extent returned [1] https://man7.org/linux/man-pages/man2/ioctl_getfsmap.2.html Reported-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Cc: stable@kernel.org Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <023f37e35ee280cd9baac0296cbadcbe10995cab.1757058211.git.ojaswin@linux.ibm.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-25ext4: increase IO priority of fastcommitJulian Sun1-1/+1
The following code paths may result in high latency or even task hangs: 1. fastcommit io is throttled by wbt. 2. jbd2_fc_wait_bufs() might wait for a long time while JBD2_FAST_COMMIT_ONGOING is set in journal->flags, and then jbd2_journal_commit_transaction() waits for the JBD2_FAST_COMMIT_ONGOING bit for a long time while holding the write lock of j_state_lock. 3. start_this_handle() waits for read lock of j_state_lock which results in high latency or task hang. Given the fact that ext4_fc_commit() already modifies the current process' IO priority to match that of the jbd2 thread, it should be reasonable to match jbd2's IO submission flags as well. Suggested-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Julian Sun <sunjunchao@bytedance.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Message-ID: <20250827121812.1477634-1-sunjunchao@bytedance.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-25ext4: remove obsolete EXT3 config optionsLukas Bulwahn1-27/+0
In June 2015, commit c290ea01abb7 ("fs: Remove ext3 filesystem driver") removed the historic ext3 filesystem support as ext3 partitions are fully supported with the ext4 filesystem support. To simplify updating the kernel build configuration, which had only EXT3 support but not EXT4 support enabled, the three config options EXT3_{FS,FS_POSIX_ACL,FS_SECURITY} were kept, instead of immediately removing them. The three options just enable the corresponding EXT4 counterparts when configs from older kernel versions are used to build on later kernel versions. This ensures that the kernels from those kernel build configurations would then continue to have EXT4 enabled for supporting booting from ext3 and ext4 file systems, to avoid potential unexpected surprises. Given that the kernel build configuration has no backwards-compatibility guarantee and this transition phase for such build configurations has been in place for a decade, we can reasonably expect all such users to have transitioned to use the EXT4 config options in their config files at this point in time. With that in mind, the three EXT3 config options are obsolete by now. Remove the obsolete EXT3 config options. Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-25ext4: fix potential null deref in ext4_mb_init()Baokun Li1-0/+10
In ext4_mb_init(), ext4_mb_avg_fragment_size_destroy() may be called when sbi->s_mb_avg_fragment_size remains uninitialized (e.g., if groupinfo slab cache allocation fails). Since ext4_mb_avg_fragment_size_destroy() lacks null pointer checking, this leads to a null pointer dereference. ================================================================== EXT4-fs: no memory for groupinfo slab cache BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: Oops: 0002 [#1] SMP PTI CPU:2 UID: 0 PID: 87 Comm:mount Not tainted 6.17.0-rc2 #1134 PREEMPT(none) RIP: 0010:_raw_spin_lock_irqsave+0x1b/0x40 Call Trace: <TASK> xa_destroy+0x61/0x130 ext4_mb_init+0x483/0x540 __ext4_fill_super+0x116d/0x17b0 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 do_new_mount+0x197/0x300 __x64_sys_mount+0x116/0x150 do_syscall_64+0x50/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== Therefore, add necessary null check to ext4_mb_avg_fragment_size_destroy() to prevent this issue. The same fix is also applied to ext4_mb_largest_free_orders_destroy(). Reported-by: syzbot+1713b1aa266195b916c2@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=1713b1aa266195b916c2 Cc: stable@kernel.org Fixes: f7eaacbb4e54 ("ext4: convert free groups order lists to xarrays") Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-25ext4: add ext4_sb_bread_nofail() helper function for ext4_free_branches()Baokun Li3-1/+12
The implicit __GFP_NOFAIL flag in ext4_sb_bread() was removed in commit 8a83ac54940d ("ext4: call bdev_getblk() from sb_getblk_gfp()"), meaning the function can now fail under memory pressure. Most callers of ext4_sb_bread() propagate the error to userspace and do not remount the filesystem read-only. However, ext4_free_branches() handles ext4_sb_bread() failure by remounting the filesystem read-only. This implies that an ext3 filesystem (mounted via the ext4 driver) could be forcibly remounted read-only due to a transient page allocation failure, which is unacceptable. To mitigate this, introduce a new helper function, ext4_sb_bread_nofail(), which explicitly uses __GFP_NOFAIL, and use it in ext4_free_branches(). Fixes: 8a83ac54940d ("ext4: call bdev_getblk() from sb_getblk_gfp()") Cc: stable@kernel.org Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-25ext4: replace min/max nesting with clamp()Xichao Zhao1-3/+3
The clamp() macro explicitly expresses the intent of constraining a value within bounds.Therefore, replacing max(min(a,b),c) with clamp(val, lo, hi) can improve code readability. Signed-off-by: Xichao Zhao <zhao.xichao@vivo.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-25fs: ext4: change GFP_KERNEL to GFP_NOFS to avoid deadlockchuguangqing1-1/+1
The parent function ext4_xattr_inode_lookup_create already uses GFP_NOFS for memory alloction, so the function ext4_xattr_inode_cache_find should use same gfp_flag. Signed-off-by: chuguangqing <chuguangqing@inspur.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-09-19fs: replace use of system_unbound_wq with system_dfl_wqMarco Crivellari1-1/+1
Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. system_unbound_wq should be the default workqueue so as not to enforce locality constraints for random work whenever it's not required. Adding system_dfl_wq to encourage its use when unbound work should be used. The old system_unbound_wq will be kept for a few release cycles. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Marco Crivellari <marco.crivellari@suse.com> Link: https://lore.kernel.org/20250916082906.77439-2-marco.crivellari@suse.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-15fs: rename generic_delete_inode() and generic_drop_inode()Mateusz Guzik1-1/+1
generic_delete_inode() is rather misleading for what the routine is doing. inode_just_drop() should be much clearer. The new naming is inconsistent with generic_drop_inode(), so rename that one as well with inode_ as the suffix. No functional changes. Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-01fs: add an icount_read helperJosef Bacik1-2/+2
Instead of doing direct access to ->i_count, add a helper to handle this. This will make it easier to convert i_count to a refcount later. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Link: https://lore.kernel.org/9bc62a84c6b9d6337781203f60837bd98fbc4a96.1756222464.git.josef@toxicpanda.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-21ext4: move verity info pointer to fs-specific part of inodeEric Biggers3-0/+9
Move the fsverity_info pointer into the filesystem-specific part of the inode by adding the field ext4_inode_info::i_verity_info and configuring fsverity_operations::inode_info_offs accordingly. This is a prerequisite for a later commit that removes inode::i_verity_info, saving memory and improving cache efficiency on filesystems that don't support fsverity. Co-developed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Link: https://lore.kernel.org/20250810075706.172910-10-ebiggers@kernel.org Acked-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-21ext4: move crypt info pointer to fs-specific part of inodeEric Biggers3-0/+9
Move the fscrypt_inode_info pointer into the filesystem-specific part of the inode by adding the field ext4_inode_info::i_crypt_info and configuring fscrypt_operations::inode_info_offs accordingly. This is a prerequisite for a later commit that removes inode::i_crypt_info, saving memory and improving cache efficiency with filesystems that don't support fscrypt. Co-developed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Link: https://lore.kernel.org/20250810075706.172910-4-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-18Merge tag 'ext4_for_linus-6.17-rc3' of ↵Linus Torvalds7-18/+36
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: - Fix fast commit checks for file systems with ea_inode enabled - Don't drop the i_version mount option on a remount - Fix FIEMAP reporting when there are holes in a bigalloc file system - Don't fail when mounting read-only when there are inodes in the orphan file - Fix hole length overflow for indirect mapped files on file systems with an 8k or 16k block file system * tag 'ext4_for_linus-6.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: jbd2: prevent softlockup in jbd2_log_do_checkpoint() ext4: fix incorrect function name in comment ext4: use kmalloc_array() for array space allocation ext4: fix hole length calculation overflow in non-extent inodes ext4: don't try to clear the orphan_present feature block device is r/o ext4: fix reserved gdt blocks handling in fsmap ext4: fix fsmap end of range reporting with bigalloc ext4: remove redundant __GFP_NOWARN ext4: fix unused variable warning in ext4_init_new_dir ext4: remove useless if check ext4: check fast symlink for ea_inode correctly ext4: preserve SB_I_VERSION on remount ext4: show the default enabled i_version option
2025-08-13ext4: fix incorrect function name in commentBaolin Liu1-1/+1
Since commit 6b730a405037 “ext4: hoist ext4_block_write_begin and replace the __block_write_begin”, the comment should be updated accordingly from "__block_write_begin" to "ext4_block_write_begin". Fixes: 6b730a405037 (“ext4: hoist ext4_block_write_begin and replace...") Signed-off-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://patch.msgid.link/20250812021709.1120716-1-liubaolin12138@163.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: use kmalloc_array() for array space allocationLiao Yuanhong1-2/+3
Replace kmalloc(size * sizeof) with kmalloc_array() for safer memory allocation and overflow prevention. Cc: stable@kernel.org Signed-off-by: Liao Yuanhong <liaoyuanhong@vivo.com> Link: https://patch.msgid.link/20250811125816.570142-1-liaoyuanhong@vivo.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: fix hole length calculation overflow in non-extent inodesZhang Yi1-2/+2
In a filesystem with a block size larger than 4KB, the hole length calculation for a non-extent inode in ext4_ind_map_blocks() can easily exceed INT_MAX. Then it could return a zero length hole and trigger the following waring and infinite in the iomap infrastructure. ------------[ cut here ]------------ WARNING: CPU: 3 PID: 434101 at fs/iomap/iter.c:34 iomap_iter_done+0x148/0x190 CPU: 3 UID: 0 PID: 434101 Comm: fsstress Not tainted 6.16.0-rc7+ #128 PREEMPT(voluntary) Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : iomap_iter_done+0x148/0x190 lr : iomap_iter+0x174/0x230 sp : ffff8000880af740 x29: ffff8000880af740 x28: ffff0000db8e6840 x27: 0000000000000000 x26: 0000000000000000 x25: ffff8000880af830 x24: 0000004000000000 x23: 0000000000000002 x22: 000001bfdbfa8000 x21: ffffa6a41c002e48 x20: 0000000000000001 x19: ffff8000880af808 x18: 0000000000000000 x17: 0000000000000000 x16: ffffa6a495ee6cd0 x15: 0000000000000000 x14: 00000000000003d4 x13: 00000000fa83b2da x12: 0000b236fc95f18c x11: ffffa6a4978b9c08 x10: 0000000000001da0 x9 : ffffa6a41c1a2a44 x8 : ffff8000880af5c8 x7 : 0000000001000000 x6 : 0000000000000000 x5 : 0000000000000004 x4 : 000001bfdbfa8000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000004004030000 x0 : 0000000000000000 Call trace: iomap_iter_done+0x148/0x190 (P) iomap_iter+0x174/0x230 iomap_fiemap+0x154/0x1d8 ext4_fiemap+0x110/0x140 [ext4] do_vfs_ioctl+0x4b8/0xbc0 __arm64_sys_ioctl+0x8c/0x120 invoke_syscall+0x6c/0x100 el0_svc_common.constprop.0+0x48/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x38/0x120 el0t_64_sync_handler+0x10c/0x138 el0t_64_sync+0x198/0x1a0 ---[ end trace 0000000000000000 ]--- Cc: stable@kernel.org Fixes: facab4d9711e ("ext4: return hole from ext4_map_blocks()") Reported-by: Qu Wenruo <wqu@suse.com> Closes: https://lore.kernel.org/linux-ext4/9b650a52-9672-4604-a765-bb6be55d1e4a@gmx.com/ Tested-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250811064532.1788289-1-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: don't try to clear the orphan_present feature block device is r/oTheodore Ts'o1-0/+2
When the file system is frozen in preparation for taking an LVM snapshot, the journal is checkpointed and if the orphan_file feature is enabled, and the orphan file is empty, we clear the orphan_present feature flag. But if there are pending inodes that need to be removed the orphan_present feature flag can't be cleared. The problem comes if the block device is read-only. In that case, we can't process the orphan inode list, so it is skipped in ext4_orphan_cleanup(). But then in ext4_mark_recovery_complete(), this results in the ext4 error "Orphan file not empty on read-only fs" firing and the file system mount is aborted. Fix this by clearing the needs_recovery flag in the block device is read-only. We do this after the call to ext4_load_and_init-journal() since there are some error checks need to be done in case the journal needs to be replayed and the block device is read-only, or if the block device containing the externa journal is read-only, etc. Cc: stable@kernel.org Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1108271 Cc: stable@vger.kernel.org Fixes: 02f310fcf47f ("ext4: Speedup ext4 orphan inode handling") Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: fix reserved gdt blocks handling in fsmapOjaswin Mujoo1-0/+8
In some cases like small FSes with no meta_bg and where the resize doesn't need extra gdt blocks as it can fit in the current one, s_reserved_gdt_blocks is set as 0, which causes fsmap to emit a 0 length entry, which is incorrect. $ mkfs.ext4 -b 65536 -O bigalloc /dev/sda 5G $ mount /dev/sda /mnt/scratch $ xfs_io -c "fsmap -d" /mnt/scartch 0: 253:48 [0..127]: static fs metadata 128 1: 253:48 [128..255]: special 102:1 128 2: 253:48 [256..255]: special 102:2 0 <---- 0 len entry 3: 253:48 [256..383]: special 102:3 128 Fix this by adding a check for this case. Cc: stable@kernel.org Fixes: 0c9ec4beecac ("ext4: support GETFSMAP ioctls") Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://patch.msgid.link/08781b796453a5770112aa96ad14c864fbf31935.1754377641.git.ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: fix fsmap end of range reporting with bigallocOjaswin Mujoo1-3/+12
With bigalloc enabled, the logic to report last extent has a bug since we try to use cluster units instead of block units. This can cause an issue where extra incorrect entries might be returned back to the user. This was flagged by generic/365 with 64k bs and -O bigalloc. ** Details of issue ** The issue was noticed on 5G 64k blocksize FS with -O bigalloc which has only 1 bg. $ xfs_io -c "fsmap -d" /mnt/scratch 0: 253:48 [0..127]: static fs metadata 128 /* sb */ 1: 253:48 [128..255]: special 102:1 128 /* gdt */ 3: 253:48 [256..383]: special 102:3 128 /* block bitmap */ 4: 253:48 [384..2303]: unknown 1920 /* flex bg empty space */ 5: 253:48 [2304..2431]: special 102:4 128 /* inode bitmap */ 6: 253:48 [2432..4351]: unknown 1920 /* flex bg empty space */ 7: 253:48 [4352..6911]: inodes 2560 8: 253:48 [6912..538623]: unknown 531712 9: 253:48 [538624..10485759]: free space 9947136 The issue can be seen with: $ xfs_io -c "fsmap -d 0 3" /mnt/scratch 0: 253:48 [0..127]: static fs metadata 128 1: 253:48 [384..2047]: unknown 1664 Only the first entry was expected to be returned but we get 2. This is because: ext4_getfsmap_datadev() first_cluster, last_cluster = 0 ... info->gfi_last = true; ext4_getfsmap_datadev_helper(sb, end_ag, last_cluster + 1, 0, info); fsb = C2B(1) = 16 fslen = 0 ... /* Merge in any relevant extents from the meta_list */ list_for_each_entry_safe(p, tmp, &info->gfi_meta_list, fmr_list) { ... // since fsb = 16, considers all metadata which starts before 16 blockno iter 1: error = ext4_getfsmap_helper(sb, info, p); // p = sb (0,1), nop info->gfi_next_fsblk = 1 iter 2: error = ext4_getfsmap_helper(sb, info, p); // p = gdt (1,2), nop info->gfi_next_fsblk = 2 iter 3: error = ext4_getfsmap_helper(sb, info, p); // p = blk bitmap (2,3), nop info->gfi_next_fsblk = 3 iter 4: error = ext4_getfsmap_helper(sb, info, p); // p = ino bitmap (18,19) if (rec_blk > info->gfi_next_fsblk) { // (18 > 3) // emits an extra entry ** BUG ** } } Fix this by directly calling ext4_getfsmap_datadev() with a dummy record that has fmr_physical set to (end_fsb + 1) instead of last_cluster + 1. By using the block instead of cluster we get the correct behavior. Replacing ext4_getfsmap_datadev_helper() with ext4_getfsmap_helper() is okay since the gfi_lastfree and metadata checks in ext4_getfsmap_datadev_helper() are anyways redundant when we only want to emit the last allocated block of the range, as we have already taken care of emitting metadata and any last free blocks. Cc: stable@kernel.org Reported-by: Disha Goel <disgoel@linux.ibm.com> Fixes: 4a622e4d477b ("ext4: fix FS_IOC_GETFSMAP handling") Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://patch.msgid.link/e7472c8535c9c5ec10f425f495366864ea12c9da.1754377641.git.ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: remove redundant __GFP_NOWARNQianfeng Rong2-2/+2
GFP_NOWAIT already includes __GFP_NOWARN, so let's remove the redundant __GFP_NOWARN. Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com> Link: https://patch.msgid.link/20250803102243.623705-4-rongqianfeng@vivo.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: fix unused variable warning in ext4_init_new_dirTheodore Ts'o1-2/+0
Cc: stable@kernel.org Fixes: 90f097b1403f ("ext4: refactor the inline directory conversion and...") Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: remove useless if checkAntonio Quartulli1-2/+0
This if branch is only jumping to 'out' which is defined just after the branch itself. Hence this is if-check is a no-op and can be removed. Address-Coverity-ID: 1647981 ("Incorrect expression (IDENTICAL_BRANCHES)") Signed-off-by: Antonio Quartulli <antonio@mandelbit.com> Link: https://patch.msgid.link/20250721200902.1071-1-antonio@mandelbit.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: check fast symlink for ea_inode correctlyAndreas Dilger1-1/+1
The check for a fast symlink in the presence of only an external xattr inode is incorrect. If a fast symlink does not have an xattr block (i_file_acl == 0), but does have an external xattr inode that increases inode i_blocks, then the check for a fast symlink will incorrectly fail and __ext4_iget()->ext4_ind_check_inode() will report the inode is corrupt when it "validates" i_data[] on the next read: # ln -s foo /mnt/tmp/bar # setfattr -h -n trusted.test \ -v "$(yes | head -n 4000)" /mnt/tmp/bar # umount /mnt/tmp # mount /mnt/tmp # ls -l /mnt/tmp ls: cannot access '/mnt/tmp/bar': Structure needs cleaning total 4 ? l?????????? ? ? ? ? ? bar # dmesg | tail -1 EXT4-fs error (device dm-8): __ext4_iget:5098: inode #24578: block 7303014: comm ls: invalid block (note that "block 7303014" = 0x6f6f66 = "foo" in LE order). ext4_inode_is_fast_symlink() should check the superblock EXT4_FEATURE_INCOMPAT_EA_INODE feature flag, not the inode EXT4_EA_INODE_FL, since the latter is only set on the xattr inode itself, and not on the inode that uses this xattr. Cc: stable@vger.kernel.org Fixes: fc82228a5e38 ("ext4: support fast symlinks from ext3 file systems") Signed-off-by: Andreas Dilger <adilger@whamcloud.com> Reviewed-by: Li Dongyang <dongyangli@ddn.com> Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com> Reviewed-by: Oleg Drokin <green@whamcloud.com> Reviewed-on: https://review.whamcloud.com/59879 Lustre-bug-id: https://jira.whamcloud.com/browse/LU-19121 Link: https://patch.msgid.link/20250717063709.757077-1-adilger@dilger.ca Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: preserve SB_I_VERSION on remountBaokun Li1-3/+3
IMA testing revealed that after an ext4 remount, file accesses triggered full measurements even without modifications, instead of skipping as expected when i_version is unchanged. Debugging showed `SB_I_VERSION` was cleared in reconfigure_super() during remount due to commit 1ff20307393e ("ext4: unconditionally enable the i_version counter") removing the fix from commit 960e0ab63b2e ("ext4: fix i_version handling on remount"). To rectify this, `SB_I_VERSION` is always set for `fc->sb_flags` in ext4_init_fs_context(), instead of `sb->s_flags` in __ext4_fill_super(), ensuring it persists across all mounts. Cc: stable@kernel.org Fixes: 1ff20307393e ("ext4: unconditionally enable the i_version counter") Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250703073903.6952-2-libaokun@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-08-12ext4: show the default enabled i_version optionBaokun Li1-0/+2
Display `i_version` in `/proc/fs/ext4/sdx/options`, even though it's default enabled. This aids users managing multi-version scenarios and simplifies debugging. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250703073903.6952-1-libaokun@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-31Merge tag 'mm-stable-2025-07-30-15-25' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "As usual, many cleanups. The below blurbiage describes 42 patchsets. 21 of those are partially or fully cleanup work. "cleans up", "cleanup", "maintainability", "rationalizes", etc. I never knew the MM code was so dirty. "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes) addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for merging with existing adjacent VMAs. "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park) adds a new kernel module which simplifies the setup and usage of DAMON in production environments. "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig) is a cleanup to the writeback code which removes a couple of pointers from struct writeback_control. "drivers/base/node.c: optimization and cleanups" (Donet Tom) contains largely uncorrelated cleanups to the NUMA node setup and management code. "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman) does some maintenance work on the userfaultfd code. "Readahead tweaks for larger folios" (Ryan Roberts) implements some tuneups for pagecache readahead when it is reading into order>0 folios. "selftests/mm: Tweaks to the cow test" (Mark Brown) provides some cleanups and consistency improvements to the selftests code. "Optimize mremap() for large folios" (Dev Jain) does that. A 37% reduction in execution time was measured in a memset+mremap+munmap microbenchmark. "Remove zero_user()" (Matthew Wilcox) expunges zero_user() in favor of the more modern memzero_page(). "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand) addresses some warts which David noticed in the huge page code. These were not known to be causing any issues at this time. "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park) provides some cleanup and consolidation work in DAMON. "use vm_flags_t consistently" (Lorenzo Stoakes) uses vm_flags_t in places where we were inappropriately using other types. "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy) increases the reliability of large page allocation in the memfd code. "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple) removes several now-unneeded PFN_* flags. "mm/damon: decouple sysfs from core" (SeongJae Park) implememnts some cleanup and maintainability work in the DAMON sysfs layer. "madvise cleanup" (Lorenzo Stoakes) does quite a lot of cleanup/maintenance work in the madvise() code. "madvise anon_name cleanups" (Vlastimil Babka) provides additional cleanups on top or Lorenzo's effort. "Implement numa node notifier" (Oscar Salvador) creates a standalone notifier for NUMA node memory state changes. Previously these were lumped under the more general memory on/offline notifier. "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan) cleans up the pageblock isolation code and fixes a potential issue which doesn't seem to cause any problems in practice. "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park) adds additional drgn- and python-based DAMON selftests which are more comprehensive than the existing selftest suite. "Misc rework on hugetlb faulting path" (Oscar Salvador) fixes a rather obscure deadlock in the hugetlb fault code and follows that fix with a series of cleanups. "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport) rationalizes and cleans up the highmem-specific code in the CMA allocator. "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand) provides cleanups and future-preparedness to the migration code. "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park) adds some tracepoints to some DAMON auto-tuning code. "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park) does that. "mm/damon: misc cleanups" (SeongJae Park) also does what it claims. "mm: folio_pte_batch() improvements" (David Hildenbrand) cleans up the large folio PTE batching code. "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park) facilitates dynamic alteration of DAMON's inter-node allocation policy. "Remove unmap_and_put_page()" (Vishal Moola) provides a couple of page->folio conversions. "mm: per-node proactive reclaim" (Davidlohr Bueso) implements a per-node control of proactive reclaim - beyond the current memcg-based implementation. "mm/damon: remove damon_callback" (SeongJae Park) replaces the damon_callback interface with a more general and powerful damon_call()+damos_walk() interface. "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes) implements a number of mremap cleanups (of course) in preparation for adding new mremap() functionality: newly permit the remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It still excludes some specialized situations where this cannot be performed reliably. "drop hugetlb_free_pgd_range()" (Anthony Yznaga) switches some sparc hugetlb code over to the generic version and removes the thus-unneeded hugetlb_free_pgd_range(). "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park) augments the present userspace-requested update of DAMON sysfs monitoring files. Automatic update is now provided, along with a tunable to control the update interval. "Some randome fixes and cleanups to swapfile" (Kemeng Shi) does what is claims. "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand) provides (and uses) a means by which debug-style functions can grab a copy of a pageframe and inspect it locklessly without tripping over the races inherent in operating on the live pageframe directly. "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan) addresses the large contention issues which can be triggered by reads from that procfs file. Latencies are reduced by more than half in some situations. The series also introduces several new selftests for the /proc/pid/maps interface. "__folio_split() clean up" (Zi Yan) cleans up __folio_split()! "Optimize mprotect() for large folios" (Dev Jain) provides some quite large (>3x) speedups to mprotect() when dealing with large folios. "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian) does some cleanup work in the selftests code. "tools/testing: expand mremap testing" (Lorenzo Stoakes) extends the mremap() selftest in several ways, including adding more checking of Lorenzo's recently added "permit mremap() move of multiple VMAs" feature. "selftests/damon/sysfs.py: test all parameters" (SeongJae Park) extends the DAMON sysfs interface selftest so that it tests all possible user-requested parameters. Rather than the present minimal subset" * tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits) MAINTAINERS: add missing headers to mempory policy & migration section MAINTAINERS: add missing file to cgroup section MAINTAINERS: add MM MISC section, add missing files to MISC and CORE MAINTAINERS: add missing zsmalloc file MAINTAINERS: add missing files to page alloc section MAINTAINERS: add missing shrinker files MAINTAINERS: move memremap.[ch] to hotplug section MAINTAINERS: add missing mm_slot.h file THP section MAINTAINERS: add missing interval_tree.c to memory mapping section MAINTAINERS: add missing percpu-internal.h file to per-cpu section mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info() selftests/damon: introduce _common.sh to host shared function selftests/damon/sysfs.py: test runtime reduction of DAMON parameters selftests/damon/sysfs.py: test non-default parameters runtime commit selftests/damon/sysfs.py: generalize DAMON context commit assertion selftests/damon/sysfs.py: generalize monitoring attributes commit assertion selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion selftests/damon/sysfs.py: test DAMOS filters commitment selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion selftests/damon/sysfs.py: test DAMOS destinations commitment ...
2025-07-31Merge tag 'ext4_for_linus_6.17-rc1' of ↵Linus Torvalds14-681/+861
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Major ext4 changes for 6.17: - Better scalability for ext4 block allocation - Fix insufficient credits when writing back large folios Miscellaneous bug fixes, especially when handling exteded attriutes, inline data, and fast commit" * tag 'ext4_for_linus_6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (39 commits) ext4: do not BUG when INLINE_DATA_FL lacks system.data xattr ext4: implement linear-like traversal across order xarrays ext4: refactor choose group to scan group ext4: convert free groups order lists to xarrays ext4: factor out ext4_mb_scan_group() ext4: factor out ext4_mb_might_prefetch() ext4: factor out __ext4_mb_scan_group() ext4: fix largest free orders lists corruption on mb_optimize_scan switch ext4: fix zombie groups in average fragment size lists ext4: merge freed extent with existing extents before insertion ext4: convert sbi->s_mb_free_pending to atomic_t ext4: fix typo in CR_GOAL_LEN_SLOW comment ext4: get rid of some obsolete EXT4_MB_HINT flags ext4: utilize multiple global goals to reduce contention ext4: remove unnecessary s_md_lock on update s_mb_last_group ext4: remove unnecessary s_mb_last_start ext4: separate stream goal hits from s_bal_goals for better tracking ext4: add ext4_try_lock_group() to skip busy groups ext4: initialize superblock fields in the kballoc-test.c kunit tests ext4: refactor the inline directory conversion and new directory codepaths ...
2025-07-28Merge tag 'vfs-6.17-rc1.fileattr' of ↵Linus Torvalds2-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull fileattr updates from Christian Brauner: "This introduces the new file_getattr() and file_setattr() system calls after lengthy discussions. Both system calls serve as successors and extensible companions to the FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR system calls which have started to show their age in addition to being named in a way that makes it easy to conflate them with extended attribute related operations. These syscalls allow userspace to set filesystem inode attributes on special files. One of the usage examples is the XFS quota projects. XFS has project quotas which could be attached to a directory. All new inodes in these directories inherit project ID set on parent directory. The project is created from userspace by opening and calling FS_IOC_FSSETXATTR on each inode. This is not possible for special files such as FIFO, SOCK, BLK etc. Therefore, some inodes are left with empty project ID. Those inodes then are not shown in the quota accounting but still exist in the directory. This is not critical but in the case when special files are created in the directory with already existing project quota, these new inodes inherit extended attributes. This creates a mix of special files with and without attributes. Moreover, special files with attributes don't have a possibility to become clear or change the attributes. This, in turn, prevents userspace from re-creating quota project on these existing files. In addition, these new system calls allow the implementation of additional attributes that we couldn't or didn't want to fit into the legacy ioctls anymore" * tag 'vfs-6.17-rc1.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: tighten a sanity check in file_attr_to_fileattr() tree-wide: s/struct fileattr/struct file_kattr/g fs: introduce file_getattr and file_setattr syscalls fs: prepare for extending file_get/setattr() fs: make vfs_fileattr_[get|set] return -EOPNOTSUPP selinux: implement inode_file_[g|s]etattr hooks lsm: introduce new hooks for setting/getting inode fsxattr fs: split fileattr related helpers into separate file
2025-07-28Merge tag 'vfs-6.17-rc1.mmap_prepare' of ↵Linus Torvalds1-6/+7
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
2025-07-28Merge tag 'vfs-6.17-rc1.fallocate' of ↵Linus Torvalds1-11/+55
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull fallocate updates from Christian Brauner: "fallocate() currently supports creating preallocated files efficiently. However, on most filesystems fallocate() will preallocate blocks in an unwriten state even if FALLOC_FL_ZERO_RANGE is specified. The extent state must later be converted to a written state when the user writes data into this range, which can trigger numerous metadata changes and journal I/O. This may leads to significant write amplification and performance degradation in synchronous write mode. At the moment, the only method to avoid this is to create an empty file and write zero data into it (for example, using 'dd' with a large block size). However, this method is slow and consumes a considerable amount of disk bandwidth. Now that more and more flash-based storage devices are available it is possible to efficiently write zeros to SSDs using the unmap write zeroes command if the devices do not write physical zeroes to the media. For example, if SCSI SSDs support the UMMAP bit or NVMe SSDs support the DEAC bit[1], the write zeroes command does not write actual data to the device, instead, NVMe converts the zeroed range to a deallocated state, which works fast and consumes almost no disk write bandwidth. This series implements the BLK_FEAT_WRITE_ZEROES_UNMAP feature and BLK_FLAG_WRITE_ZEROES_UNMAP_DISABLED flag for SCSI, NVMe and device-mapper drivers, and add the FALLOC_FL_WRITE_ZEROES and STATX_ATTR_WRITE_ZEROES_UNMAP support for ext4 and raw bdev devices. fallocate() is subsequently extended with the FALLOC_FL_WRITE_ZEROES flag. FALLOC_FL_WRITE_ZEROES zeroes a specified file range in such a way that subsequent writes to that range do not require further changes to the file mapping metadata. This flag is beneficial for subsequent pure overwriting within this range, as it can save on block allocation and, consequently, significant metadata changes" * tag 'vfs-6.17-rc1.fallocate' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: ext4: add FALLOC_FL_WRITE_ZEROES support block: add FALLOC_FL_WRITE_ZEROES support block: factor out common part in blkdev_fallocate() fs: introduce FALLOC_FL_WRITE_ZEROES to fallocate dm: clear unmap write zeroes limits when disabling write zeroes scsi: sd: set max_hw_wzeroes_unmap_sectors if device supports SD_ZERO_*_UNMAP nvmet: set WZDS and DRB if device enables unmap write zeroes operation nvme: set max_hw_wzeroes_unmap_sectors if device supports DEAC bit block: introduce max_{hw|user}_wzeroes_unmap_sectors to queue limits
2025-07-25ext4: do not BUG when INLINE_DATA_FL lacks system.data xattrTheodore Ts'o1-3/+16
A syzbot fuzzed image triggered a BUG_ON in ext4_update_inline_data() when an inode had the INLINE_DATA_FL flag set but was missing the system.data extended attribute. Since this can happen due to a maiciouly fuzzed file system, we shouldn't BUG, but rather, report it as a corrupted file system. Add similar replacements of BUG_ON with EXT4_ERROR_INODE() ii ext4_create_inline_data() and ext4_inline_data_truncate(). Reported-by: syzbot+544248a761451c0df72f@syzkaller.appspotmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: implement linear-like traversal across order xarraysBaokun Li1-21/+47
Although we now perform ordered traversal within an xarray, this is currently limited to a single xarray. However, we have multiple such xarrays, which prevents us from guaranteeing a linear-like traversal where all groups on the right are visited before all groups on the left. For example, suppose we have 128 block groups, with a target group of 64, a target length corresponding to an order of 1, and available free groups of 16 (order 1) and group 65 (order 8): For linear traversal, when no suitable free block is found in group 64, it will search in the next block group until group 127, then start searching from 0 up to block group 63. It ensures continuous forward traversal, which is consistent with the unidirectional rotation behavior of HDD platters. Additionally, the block group lock contention during freeing block is unavoidable. The goal increasing from 0 to 64 indicates that previously scanned groups (which had no suitable free space and are likely to free blocks later) and skipped groups (which are currently in use) have newly freed some used blocks. If we allocate blocks in these groups, the probability of competing with other processes increases. For non-linear traversal, we first traverse all groups in order_1. If only group 16 has free space in this list, we first traverse [63, 128), then traverse [0, 64) to find the available group 16, and then allocate blocks in group 16. Therefore, it cannot guarantee continuous traversal in one direction, thus increasing the probability of contention. So refactor ext4_mb_scan_groups_xarray() to ext4_mb_scan_groups_xa_range() to only traverse a fixed range of groups, and move the logic for handling wrap around to the caller. The caller first iterates through all xarrays in the range [start, ngroups) and then through the range [0, start). This approach simulates a linear scan, which reduces contention between freeing blocks and allocating blocks. Assume we have the following groups, where "|" denotes the xarray traversal start position: order_1_groups: AB | CD order_2_groups: EF | GH Traversal order: Before: C > D > A > B > G > H > E > F After: C > D > G > H > A > B > E > F Performance test data follows: |CPU: Kunpeng 920 | P80 | P1 | |Memory: 512GB |------------------------|-------------------------| |960GB SSD (0.5GB/s)| base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 19555 | 20049 (+2.5%) | 315636 | 316724 (-0.3%) | |mb_optimize_scan=1 | 15496 | 19342 (+24.8%) | 323569 | 328324 (+1.4%) | |CPU: AMD 9654 * 2 | P96 | P1 | |Memory: 1536GB |------------------------|-------------------------| |960GB SSD (1GB/s) | base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 53192 | 52125 (-2.0%) | 212678 | 215136 (+1.1%) | |mb_optimize_scan=1 | 37636 | 50331 (+33.7%) | 214189 | 209431 (-2.2%) | Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-18-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: refactor choose group to scan groupBaokun Li3-174/+131
This commit converts the `choose group` logic to `scan group` using previously prepared helper functions. This allows us to leverage xarrays for ordered non-linear traversal, thereby mitigating the "bouncing" issue inherent in the `choose group` mechanism. This also decouples linear and non-linear traversals, leading to cleaner and more readable code. Key changes: * ext4_mb_choose_next_group() is refactored to ext4_mb_scan_groups(). * Replaced ext4_mb_good_group() with ext4_mb_scan_group() in non-linear traversals, and related functions now return error codes instead of group info. * Added ext4_mb_scan_groups_linear() for performing linear scans starting from a specific group for a set number of times. * Linear scans now execute up to sbi->s_mb_max_linear_groups times, so ac_groups_linear_remaining is removed as it's no longer used. * ac->ac_criteria is now used directly instead of passing cr around. Also, ac->ac_criteria is incremented directly after groups scan fails for the corresponding criteria. * Since we're now directly scanning groups instead of finding a good group then scanning, the following variables and flags are no longer needed, s_bal_cX_groups_considered is sufficient. s_bal_p2_aligned_bad_suggestions s_bal_goal_fast_bad_suggestions s_bal_best_avail_bad_suggestions EXT4_MB_CR_POWER2_ALIGNED_OPTIMIZED EXT4_MB_CR_GOAL_LEN_FAST_OPTIMIZED EXT4_MB_CR_BEST_AVAIL_LEN_OPTIMIZED Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-17-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: convert free groups order lists to xarraysBaokun Li3-126/+140
While traversing the list, holding a spin_lock prevents load_buddy, making direct use of ext4_try_lock_group impossible. This can lead to a bouncing scenario where spin_is_locked(grp_A) succeeds, but ext4_try_lock_group() fails, forcing the list traversal to repeatedly restart from grp_A. In contrast, linear traversal directly uses ext4_try_lock_group(), avoiding this bouncing. Therefore, we need a lockless, ordered traversal to achieve linear-like efficiency. Therefore, this commit converts both average fragment size lists and largest free order lists into ordered xarrays. In an xarray, the index represents the block group number and the value holds the block group information; a non-empty value indicates the block group's presence. While insertion and deletion complexity remain O(1), lookup complexity changes from O(1) to O(nlogn), which may slightly reduce single-threaded performance. Additionally, xarray insertions might fail, potentially due to memory allocation issues. However, since we have linear traversal as a fallback, this isn't a major problem. Therefore, we've only added a warning message for insertion failures here. A helper function ext4_mb_find_good_group_xarray() is added to find good groups in the specified xarray starting at the specified position start, and when it reaches ngroups-1, it wraps around to 0 and then to start-1. This ensures an ordered traversal within the xarray. Performance test results are as follows: Single-process operations on an empty disk show negligible impact, while multi-process workloads demonstrate a noticeable performance gain. |CPU: Kunpeng 920 | P80 | P1 | |Memory: 512GB |------------------------|-------------------------| |960GB SSD (0.5GB/s)| base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 20097 | 19555 (-2.6%) | 316141 | 315636 (-0.2%) | |mb_optimize_scan=1 | 13318 | 15496 (+16.3%) | 325273 | 323569 (-0.5%) | |CPU: AMD 9654 * 2 | P96 | P1 | |Memory: 1536GB |------------------------|-------------------------| |960GB SSD (1GB/s) | base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 53603 | 53192 (-0.7%) | 214243 | 212678 (-0.7%) | |mb_optimize_scan=1 | 20887 | 37636 (+80.1%) | 213632 | 214189 (+0.2%) | [ Applied spelling fixes per discussion on the ext4-list see thread referened in the Link tag. --tytso] Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-16-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: factor out ext4_mb_scan_group()Baokun Li2-44/+51
Extract ext4_mb_scan_group() to make the code clearer and to prepare for the later conversion of 'choose group' to 'scan groups'. No functional changes. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-15-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: factor out ext4_mb_might_prefetch()Baokun Li2-24/+42
Extract ext4_mb_might_prefetch() to make the code clearer and to prepare for the later conversion of 'choose group' to 'scan groups'. No functional changes. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-14-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: factor out __ext4_mb_scan_group()Baokun Li2-18/+29
Extract __ext4_mb_scan_group() to make the code clearer and to prepare for the later conversion of 'choose group' to 'scan groups'. No functional changes. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-13-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: fix largest free orders lists corruption on mb_optimize_scan switchBaokun Li1-19/+14
The grp->bb_largest_free_order is updated regardless of whether mb_optimize_scan is enabled. This can lead to inconsistencies between grp->bb_largest_free_order and the actual s_mb_largest_free_orders list index when mb_optimize_scan is repeatedly enabled and disabled via remount. For example, if mb_optimize_scan is initially enabled, largest free order is 3, and the group is in s_mb_largest_free_orders[3]. Then, mb_optimize_scan is disabled via remount, block allocations occur, updating largest free order to 2. Finally, mb_optimize_scan is re-enabled via remount, more block allocations update largest free order to 1. At this point, the group would be removed from s_mb_largest_free_orders[3] under the protection of s_mb_largest_free_orders_locks[2]. This lock mismatch can lead to list corruption. To fix this, whenever grp->bb_largest_free_order changes, we now always attempt to remove the group from its old order list. However, we only insert the group into the new order list if `mb_optimize_scan` is enabled. This approach helps prevent lock inconsistencies and ensures the data in the order lists remains reliable. Fixes: 196e402adf2e ("ext4: improve cr 0 / cr 1 group scanning") CC: stable@vger.kernel.org Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-12-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: fix zombie groups in average fragment size listsBaokun Li1-18/+18
Groups with no free blocks shouldn't be in any average fragment size list. However, when all blocks in a group are allocated(i.e., bb_fragments or bb_free is 0), we currently skip updating the average fragment size, which means the group isn't removed from its previous s_mb_avg_fragment_size[old] list. This created "zombie" groups that were always skipped during traversal as they couldn't satisfy any block allocation requests, negatively impacting traversal efficiency. Therefore, when a group becomes completely full, bb_avg_fragment_size_order is now set to -1. If the old order was not -1, a removal operation is performed; if the new order is not -1, an insertion is performed. Fixes: 196e402adf2e ("ext4: improve cr 0 / cr 1 group scanning") CC: stable@vger.kernel.org Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-11-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: merge freed extent with existing extents before insertionBaokun Li1-37/+76
Attempt to merge ext4_free_data with already inserted free extents prior to adding new ones. This strategy drastically cuts down the number of times locks are held. For example, if prev, new, and next extents are all mergeable, the existing code (before this patch) requires acquiring the s_md_lock three times: prev merge into new and free prev // hold lock next merge into new and free next // hold lock insert new // hold lock After the patch, it only needs to be acquired once: new merge into next and free new // no lock next merge into prev and free next // hold lock Performance test data follows: Test: Running will-it-scale/fallocate2 on CPU-bound containers. Observation: Average fallocate operations per container per second. |CPU: Kunpeng 920 | P80 | P1 | |Memory: 512GB |------------------------|-------------------------| |960GB SSD (0.5GB/s)| base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 20043 | 20097 (+0.2%) | 314331 | 316141 (+0.5%) | |mb_optimize_scan=1 | 7290 | 13318 (+87.4%) | 324226 | 325273 (+0.3%) | |CPU: AMD 9654 * 2 | P96 | P1 | |Memory: 1536GB |------------------------|-------------------------| |960GB SSD (1GB/s) | base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 54999 | 53603 (-2.5%) | 214380 | 214243 (-0.06%)| |mb_optimize_scan=1 | 13497 | 20887 (+54.6%) | 216276 | 213632 (-1.2%) | Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-10-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: convert sbi->s_mb_free_pending to atomic_tBaokun Li3-8/+5
Previously, s_md_lock was used to protect s_mb_free_pending during modifications, while smp_mb() ensured fresh reads, so s_md_lock just guarantees the atomicity of s_mb_free_pending. Thus we optimized it by converting s_mb_free_pending into an atomic variable, thereby eliminating s_md_lock and minimizing lock contention. This also prepares for future lockless merging of free extents. Following this modification, s_md_lock is exclusively responsible for managing insertions and deletions within s_freed_data_list, along with operations involving list_splice. Performance test data follows: Test: Running will-it-scale/fallocate2 on CPU-bound containers. Observation: Average fallocate operations per container per second. |CPU: Kunpeng 920 | P80 | P1 | |Memory: 512GB |------------------------|-------------------------| |960GB SSD (0.5GB/s)| base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 19628 | 20043 (+2.1%) | 320885 | 314331 (-2.0%) | |mb_optimize_scan=1 | 7129 | 7290 (+2.2%) | 321275 | 324226 (+0.9%) | |CPU: AMD 9654 * 2 | P96 | P1 | |Memory: 1536GB |------------------------|-------------------------| |960GB SSD (1GB/s) | base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 53760 | 54999 (+2.3%) | 213145 | 214380 (+0.5%) | |mb_optimize_scan=1 | 12716 | 13497 (+6.1%) | 215262 | 216276 (+0.4%) | Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-9-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: fix typo in CR_GOAL_LEN_SLOW commentBaokun Li1-1/+1
Remove the superfluous "find_". Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-8-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: get rid of some obsolete EXT4_MB_HINT flagsBaokun Li1-6/+0
Since nobody has used these EXT4_MB_HINT flags for ages, let's remove them. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-7-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: utilize multiple global goals to reduce contentionBaokun Li2-6/+27
When allocating data blocks, if the first try (goal allocation) fails and stream allocation is on, it tries a global goal starting from the last group we used (s_mb_last_group). This helps cluster large files together to reduce free space fragmentation, and the data block contiguity also accelerates write-back to disk. However, when multiple processes allocate blocks, having just one global goal means they all fight over the same group. This drastically lowers the chances of extents merging and leads to much worse file fragmentation. To mitigate this multi-process contention, we now employ multiple global goals, with the number of goals being the minimum between the number of possible CPUs and one-quarter of the filesystem's total block group count. To ensure a consistent goal for each inode, we select the corresponding goal by taking the inode number modulo the total number of goals. Performance test data follows: Test: Running will-it-scale/fallocate2 on CPU-bound containers. Observation: Average fallocate operations per container per second. |CPU: Kunpeng 920 | P80 | P1 | |Memory: 512GB |------------------------|-------------------------| |960GB SSD (0.5GB/s)| base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 9636 | 19628 (+103%) | 337597 | 320885 (-4.9%) | |mb_optimize_scan=1 | 4834 | 7129 (+47.4%) | 341440 | 321275 (-5.9%) | |CPU: AMD 9654 * 2 | P96 | P1 | |Memory: 1536GB |------------------------|-------------------------| |960GB SSD (1GB/s) | base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 22341 | 53760 (+140%) | 219707 | 213145 (-2.9%) | |mb_optimize_scan=1 | 9177 | 12716 (+38.5%) | 215732 | 215262 (+0.2%) | Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-6-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: remove unnecessary s_md_lock on update s_mb_last_groupBaokun Li2-10/+4
After we optimized the block group lock, we found another lock contention issue when running will-it-scale/fallocate2 with multiple processes. The fallocate's block allocation and the truncate's block release were fighting over the s_md_lock. The problem is, this lock protects totally different things in those two processes: the list of freed data blocks (s_freed_data_list) when releasing, and where to start looking for new blocks (mb_last_group) when allocating. Now we only need to track s_mb_last_group and no longer need to track s_mb_last_start, so we don't need the s_md_lock lock to ensure that the two are consistent. Since s_mb_last_group is merely a hint and doesn't require strong synchronization, READ_ONCE/WRITE_ONCE is sufficient. Besides, the s_mb_last_group data type only requires ext4_group_t (i.e., unsigned int), rendering unsigned long superfluous. Performance test data follows: Test: Running will-it-scale/fallocate2 on CPU-bound containers. Observation: Average fallocate operations per container per second. |CPU: Kunpeng 920 | P80 | P1 | |Memory: 512GB |------------------------|-------------------------| |960GB SSD (0.5GB/s)| base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 4821 | 9636 (+99.8%) | 314065 | 337597 (+7.4%) | |mb_optimize_scan=1 | 4784 | 4834 (+1.04%) | 316344 | 341440 (+7.9%) | |CPU: AMD 9654 * 2 | P96 | P1 | |Memory: 1536GB |------------------------|-------------------------| |960GB SSD (1GB/s) | base | patched | base | patched | |-------------------|-------|----------------|--------|----------------| |mb_optimize_scan=0 | 15371 | 22341 (+45.3%) | 205851 | 219707 (+6.7%) | |mb_optimize_scan=1 | 6101 | 9177 (+50.4%) | 207373 | 215732 (+4.0%) | Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-5-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: remove unnecessary s_mb_last_startBaokun Li2-2/+0
Since stream allocation does not use ac->ac_f_ex.fe_start, it is set to -1 by default, so the no longer needed sbi->s_mb_last_start is removed. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-4-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: separate stream goal hits from s_bal_goals for better trackingBaokun Li2-2/+10
In ext4_mb_regular_allocator(), after the call to ext4_mb_find_by_goal() fails to achieve the inode goal, allocation continues with the stream allocation global goal. Currently, hits for both are combined in sbi->s_bal_goals, hindering accurate optimization. This commit separates global goal hits into sbi->s_bal_stream_goals. Since stream allocation doesn't use ac->ac_g_ex.fe_start, set fe_start to -1. This prevents stream allocations from being counted in s_bal_goals. Also clear EXT4_MB_HINT_TRY_GOAL to avoid calling ext4_mb_find_by_goal again. After adding `stream_goal_hits`, `/proc/fs/ext4/sdx/mb_stats` will show: mballoc: reqs: 840347 success: 750992 groups_scanned: 1230506 cr_p2_aligned_stats: hits: 21531 groups_considered: 411664 extents_scanned: 21531 useless_loops: 0 bad_suggestions: 6 cr_goal_fast_stats: hits: 111222 groups_considered: 1806728 extents_scanned: 467908 useless_loops: 0 bad_suggestions: 13 cr_best_avail_stats: hits: 36267 groups_considered: 1817631 extents_scanned: 156143 useless_loops: 0 bad_suggestions: 204 cr_goal_slow_stats: hits: 106396 groups_considered: 5671710 extents_scanned: 22540056 useless_loops: 123747 cr_any_free_stats: hits: 138071 groups_considered: 724692 extents_scanned: 23615593 useless_loops: 585 extents_scanned: 46804261 goal_hits: 1307 stream_goal_hits: 236317 len_goal_hits: 155549 2^n_hits: 21531 breaks: 225096 lost: 35062 buddies_generated: 40/40 buddies_time_used: 48004 preallocated: 5962467 discarded: 4847560 Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-3-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: add ext4_try_lock_group() to skip busy groupsBaokun Li2-12/+30
When ext4 allocates blocks, we used to just go through the block groups one by one to find a good one. But when there are tons of block groups (like hundreds of thousands or even millions) and not many have free space (meaning they're mostly full), it takes a really long time to check them all, and performance gets bad. So, we added the "mb_optimize_scan" mount option (which is on by default now). It keeps track of some group lists, so when we need a free block, we can just grab a likely group from the right list. This saves time and makes block allocation much faster. But when multiple processes or containers are doing similar things, like constantly allocating 8k blocks, they all try to use the same block group in the same list. Even just two processes doing this can cut the IOPS in half. For example, one container might do 300,000 IOPS, but if you run two at the same time, the total is only 150,000. Since we can already look at block groups in a non-linear way, the first and last groups in the same list are basically the same for finding a block right now. Therefore, add an ext4_try_lock_group() helper function to skip the current group when it is locked by another process, thereby avoiding contention with other processes. This helps ext4 make better use of having multiple block groups. Also, to make sure we don't skip all the groups that have free space when allocating blocks, we won't try to skip busy groups anymore when ac_criteria is CR_ANY_FREE. Performance test data follows: Test: Running will-it-scale/fallocate2 on CPU-bound containers. Observation: Average fallocate operations per container per second. |CPU: Kunpeng 920 | P80 | |Memory: 512GB |-------------------------| |960GB SSD (0.5GB/s)| base | patched | |-------------------|-------|-----------------| |mb_optimize_scan=0 | 2667 | 4821 (+80.7%) | |mb_optimize_scan=1 | 2643 | 4784 (+81.0%) | |CPU: AMD 9654 * 2 | P96 | |Memory: 1536GB |-------------------------| |960GB SSD (1GB/s) | base | patched | |-------------------|-------|-----------------| |mb_optimize_scan=0 | 3450 | 15371 (+345%) | |mb_optimize_scan=1 | 3209 | 6101 (+90.0%) | Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250714130327.1830534-2-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-25ext4: initialize superblock fields in the kballoc-test.c kunit testsZhang Yi1-0/+9
Various changes in the "ext4: better scalability for ext4 block allocation" patch series have resulted in kunit test failures, most notably in the test_new_blocks_simple and the test_mb_mark_used tests. The root cause of these failures is that various in-memory ext4 data structures were not getting initialized, and while previous versions of the functions exercised by the unit tests didn't use these structure members, this was arguably a test bug. Since one of the patches in the block allocation scalability patches is a fix which is has a cc:stable tag, this commit also has a cc:stable tag. CC: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250714130327.1830534-1-libaokun1@huawei.com Link: https://patch.msgid.link/20250725021550.3177573-1-yi.zhang@huaweicloud.com Link: https://patch.msgid.link/20250725021654.3188798-1-yi.zhang@huaweicloud.com Reported-by: Guenter Roeck <linux@roeck-us.net> Closes: https://lore.kernel.org/linux-ext4/b0635ad0-7ebf-4152-a69b-58e7e87d5085@roeck-us.net/ Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-17ext4: refactor the inline directory conversion and new directory codepathsTheodore Ts'o3-77/+48
There was a lot of common code in the codepaths used to convert an inline directory and to creaet a new directory. To address this, rename ext4_init_dot_dotdot() to ext4_init_dirblock() and then move common code into that function. This reduces the lines of code count in fs/ext4/inline.c and fs/ext4/namei.c, as well as reducing the size of their object files. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Link: https://patch.msgid.link/20250712181249.434530-3-tytso@mit.edu Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-17ext4: use memcpy() instead of strcpy()Theodore Ts'o2-4/+4
The strcpy() function is considered dangerous and eeeevil by people who are using sophisticated code analysis tools such as "grep". This is true even when a quick inspection would show that the source is a constant string ("." or "..") and the destination is a fixed array which is guaranteed to have enough space. Make the "grep" code analysis tool happy by using memcpy() isstead of strcpy(). :-) Signed-off-by: Theodore Ts'o <tytso@mit.edu> Link: https://patch.msgid.link/20250712181249.434530-2-tytso@mit.edu Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-17ext4: replace strcmp with direct comparison for '.' and '..'Theodore Ts'o1-4/+7
In a discussion over a proposed patch, "ext4: replace strcpy() with '.' assignment"[1], I had asserted that directory entries in ext4 were not NUL terminated, and hence it was safe to replace strcpy() with a direct assignment. As it turns out, this was incorrect. It's true for all all directory entries *except* for '.' and '..' where the kernel was using strcmp() and where e2fsck actually checks and offers to fix things if '.' and '..' are not NUL terminated. [1] https://lore.kernel.org/r/202505191316.JJMnPobO-lkp@intel.com We can't change this without breaking old kernel versions, but in the spirit of "be liberal in what you receive", use direct comparison of de->name_len and de->name[0,1] instead of strcmp(). This has the side benefit of reducing the compiled text size by 96 bytes on x86_64. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Link: https://patch.msgid.link/20250712181249.434530-1-tytso@mit.edu Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-17ext4: Make sure BH_New bit is cleared in ->write_end handlerJan Kara2-1/+4
Currently we clear BH_New bit in case of error and also in the standard ext4_write_end() handler (in block_commit_write()). However ext4_journalled_write_end() misses this clearing and thus we are leaving stale BH_New bits behind. Generally ext4_block_write_begin() clears these bits before any harm can be done but in case blocksize < pagesize and we hit some error when processing a page with these stale bits, we'll try to zero buffers with these stale BH_New bits and jbd2 will complain (as buffers were not prepared for writing in this transaction). Fix the problem by clearing BH_New bits in ext4_journalled_write_end() and WARN if ext4_block_write_begin() sees stale BH_New bits. Reported-by: Baolin Liu <liubaolin12138@163.com> Reported-by: Zhi Long <longzhi@sangfor.com.cn> Fixes: 3910b513fcdf ("ext4: persist the new uptodate buffers in ext4_journalled_zero_new_buffers") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250709084831.23876-2-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-17ext4: fix inode use after free in ext4_end_io_rsv_work()Baokun Li1-8/+8
In ext4_io_end_defer_completion(), check if io_end->list_vec is empty to avoid adding an io_end that requires no conversion to the i_rsv_conversion_list, which in turn prevents starting an unnecessary worker. An ext4_emergency_state() check is also added to avoid attempting to abort the journal in an emergency state. Additionally, ext4_put_io_end_defer() is refactored to call ext4_io_end_defer_completion() directly instead of being open-coded. This also prevents starting an unnecessary worker when EXT4_IO_END_FAILED is set but data_err=abort is not enabled. This ensures that the check in ext4_put_io_end_defer() is consistent with the check in ext4_end_bio(). Otherwise, we might add an io_end to the i_rsv_conversion_list and then call ext4_finish_bio(), after which the inode could be freed before ext4_end_io_rsv_work() is called, triggering a use-after-free issue. Fixes: ce51afb8cc5e ("ext4: abort journal on data writeback failure if in data_err=abort mode") Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250708111504.3208660-1-libaokun@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-17ext4: Refactor breaking condition for xattr_find_entry()I Hsin Cheng1-1/+1
Refactor the condition for breaking the loop within xattr_find_entry(). Elimate the usage of "<=" and take condition shortcut when "!cmp" is true. Originally, the condition was "(cmp <= 0 && (sorted || cmp == 0))", which means after it knows "cmp <= 0" is true, it has to check the value of "sorted" and "cmp". The checking of "cmp" here would be redundant since it has already checked it. Observing from the logic, when "cmp == 0" the branch is going to be true, no need to check "cmp == 0" again, so we only need to take shortcut when "cmp == 0", on the other hand, we'll check "sorted" when "cmp < 0". The refactor can shrink the generated code size by 44 bytes. Numerous instructions can be saved thus should also benefit execution efficiency as well. $ ./scripts/bloat-o-meter vmlinux_old vmlinux_new add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-44 (-44) Function old new delta xattr_find_entry 300 256 -44 Total: Before=22989434, After=22989390, chg -0.00% The test is done on kernel version 6.16 with x86_64 defconfig and gcc 13.3.0. Signed-off-by: I Hsin Cheng <richard120310@gmail.com> Link: https://patch.msgid.link/20250708020013.175728-1-richard120310@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-16ext4: support uncached buffered I/OTaotao Chen2-10/+5
Set FOP_DONTCACHE in ext4_file_operations to declare support for uncached buffered I/O. To handle this flag, update ext4_write_begin() and ext4_da_write_begin() to use write_begin_get_folio(), which encapsulates FGP_DONTCACHE logic based on iocb->ki_flags. Part of a series refactoring address_space_operations write_begin and write_end callbacks to use struct kiocb for passing write context and flags. Signed-off-by: Taotao Chen <chentaotao@didiglobal.com> Link: https://lore.kernel.org/20250716093559.217344-6-chentaotao@didiglobal.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-16fs: change write_begin/write_end interface to take struct kiocb *Taotao Chen1-8/+10
Change the address_space_operations callbacks write_begin() and write_end() to take struct kiocb * as the first argument instead of struct file *. Update all affected function prototypes, implementations, call sites, and related documentation across VFS, filesystems, and block layer. Part of a series refactoring address_space_operations write_begin and write_end callbacks to use struct kiocb for passing write context and flags. Signed-off-by: Taotao Chen <chentaotao@didiglobal.com> Link: https://lore.kernel.org/20250716093559.217344-4-chentaotao@didiglobal.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14ext4: limit the maximum folio orderZhang Yi3-6/+21
In environments with a page size of 64KB, the maximum size of a folio can reach up to 128MB. Consequently, during the write-back of folios, the 'rsv_blocks' will be overestimated to 1,577, which can make pressure on the journal space where the journal is small. This can easily exceed the limit of a single transaction. Besides, an excessively large folio is meaningless and will instead increase the overhead of traversing the bhs within the folio. Therefore, limit the maximum order of a folio to 2048 filesystem blocks. Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Reported-by: Joseph Qi <jiangqi903@gmail.com> Closes: https://lore.kernel.org/linux-ext4/CA+G9fYsyYQ3ZL4xaSg1-Tt5Evto7Zd+hgNWZEa9cQLbahA1+xg@mail.gmail.com/ Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-12-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: fix insufficient credits calculation in ext4_meta_trans_blocks()Zhang Yi1-2/+2
The calculation of journal credits in ext4_meta_trans_blocks() should include pextents, as each extent separately may be allocated from a different group and thus need to update different bitmap and group descriptor block. Fixes: 0e32d8617012 ("ext4: correct the journal credits calculations of allocating blocks") Reported-by: Jan Kara <jack@suse.cz> Closes: https://lore.kernel.org/linux-ext4/nhxfuu53wyacsrq7xqgxvgzcggyscu2tbabginahcygvmc45hy@t4fvmyeky33e/ Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250707140814.542883-11-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: replace ext4_writepage_trans_blocks()Zhang Yi6-27/+25
After ext4 supports large folios, the semantics of reserving credits in pages is no longer applicable. In most scenarios, reserving credits in extents is sufficient. Therefore, introduce ext4_chunk_trans_extent() to replace ext4_writepage_trans_blocks(). move_extent_per_page() is the only remaining location where we are still processing extents in pages. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-10-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: reserved credits for one extent during the folio writebackZhang Yi1-17/+8
After ext4 supports large folios, reserving journal credits for one maximum-ordered folio based on the worst case cenario during the writeback process can easily exceed the maximum transaction credits. Additionally, reserving journal credits for one page is also no longer appropriate. Currently, the folio writeback process can either extend the journal credits or initiate a new transaction if the currently reserved journal credits are insufficient. Therefore, it can be modified to reserve credits for only one extent at the outset. In most cases involving continuous mapping, these credits are generally adequate, and we may only need to perform some basic credit expansion. However, in extreme cases where the block size and folio size differ significantly, or when the folios are sufficiently discontinuous, it may be necessary to restart a new transaction and resubmit the folios. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-9-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: correct the reserved credits for extent conversionZhang Yi1-3/+3
Now, we reserve journal credits for converting extents in only one page to written state when the I/O operation is complete. This is insufficient when large folio is enabled. Fix this by reserving credits for converting up to one extent per block in the largest 2MB folio, this calculation should only involve extents index and leaf blocks, so it should not estimate too many credits. Fixes: 7ac67301e82f ("ext4: enable large folio for regular file") Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250707140814.542883-8-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: enhance tracepoints during the folios writebackZhang Yi1-1/+4
After mpage_map_and_submit_extent() supports restarting handle if credits are insufficient during allocating blocks, it is more likely to exit the current mapping iteration and continue to process the current processing partially mapped folio again. The existing tracepoints are not sufficient to track this situation, so enhance the tracepoints to track the writeback position and the return value before and after submitting the folios. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-7-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: restart handle if credits are insufficient during allocating blocksZhang Yi1-5/+36
After large folios are supported on ext4, writing back a sufficiently large and discontinuous folio may consume a significant number of journal credits, placing considerable strain on the journal. For example, in a 20GB filesystem with 1K block size and 1MB journal size, writing back a 2MB folio could require thousands of credits in the worst-case scenario (when each block is discontinuous and distributed across different block groups), potentially exceeding the journal size. This issue can also occur in ext4_write_begin() and ext4_page_mkwrite() when delalloc is not enabled. Fix this by ensuring that there are sufficient journal credits before allocating an extent in mpage_map_one_extent() and ext4_block_write_begin(). If there are not enough credits, return -EAGAIN, exit the current mapping loop, restart a new handle and a new transaction, and allocating blocks on this folio again in the next iteration. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-6-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: refactor the block allocation process of ext4_page_mkwrite()Zhang Yi1-45/+50
The block allocation process and error handling in ext4_page_mkwrite() is complex now. Refactor it by introducing a new helper function, ext4_block_page_mkwrite(). It will call ext4_block_write_begin() to allocate blocks instead of directly calling block_page_mkwrite(). Preparing to implement retry logic in a subsequent patch to address situations where the reserved journal credits are insufficient. Additionally, this modification will help prevent potential deadlocks that may occur when waiting for folio writeback while holding the transaction handle. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-5-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: fix stale data if it bail out of the extents mapping loopZhang Yi1-1/+50
During the process of writing back folios, if mpage_map_and_submit_extent() exits the extent mapping loop due to an ENOSPC or ENOMEM error, it may result in stale data or filesystem inconsistency in environments where the block size is smaller than the folio size. When mapping a discontinuous folio in mpage_map_and_submit_extent(), some buffers may have already be mapped. If we exit the mapping loop prematurely, the folio data within the mapped range will not be written back, and the file's disk size will not be updated. Once the transaction that includes this range of extents is committed, this can lead to stale data or filesystem inconsistency. Fix this by submitting the current processing partially mapped folio. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-4-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: move the calculation of wbc->nr_to_write to mpage_folio_done()Zhang Yi1-2/+1
mpage_folio_done() should be a more appropriate place than mpage_submit_folio() for updating the wbc->nr_to_write after we have submitted a fully mapped folio. Preparing to make mpage_submit_folio() allows to submit partially mapped folio that is still under processing. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250707140814.542883-3-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-13ext4: process folios writeback in bytesZhang Yi1-34/+36
Since ext4 supports large folios, processing writebacks in pages is no longer appropriate, it can be modified to process writebacks in bytes. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250707140814.542883-2-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-12ext4: remove unused EXT_STATS macro from ext4_extents.hBaolin Liu1-7/+0
The EXT_STATS macro in fs/ext4/ext4_extents.h has been defined but never used in the codebase since its introduction. This patch removes it. Analysis: 1. No references found in fs/ext4/ or other kernel code. 2. No impact on compilation or functionality. 3. Git history shows it was never utilized. Signed-off-by: Baolin Liu <liubaolin@kylinos.cn> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250527053805.1550912-1-liubaolin12138@163.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-11ext4: remove unnecessary duplicate check in ext4_map_blocks()Dan Carpenter1-2/+1
The previous lines ensure that EXT4_GET_BLOCKS_QUERY_LAST_IN_LEAF is set so remove this duplicate check. Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/aDCdjUhpzxB64vkD@stanley.mountain Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-10ext4: remove duplicate check for EXT4_FC_REPLAYJinliang Zheng1-2/+1
EXT4_FC_REPLAY will be checked in ext4_es_lookup_extent(). If it is set, ext4_es_lookup_extent() will return 0. Remove the repeated check for EXT4_FC_REPLAY in ext4_map_blocks() to simplify the code. Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250429111722.294975-1-alexjlzheng@tencent.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-07-09mm: remove callers of pfn_t functionalityAlistair Popple1-1/+1
All PFN_* pfn_t flags have been removed. Therefore there is no longer a need for the pfn_t type and all uses can be replaced with normal pfns. Link: https://lkml.kernel.org/r/bbedfa576c9822f8032494efbe43544628698b1f.1750323463.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <balbirs@nvidia.com> Cc: Björn Töpel <bjorn@kernel.org> Cc: Björn Töpel <bjorn@rivosinc.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Inki Dae <m.szyprowski@samsung.com> Cc: John Groves <john@groves.net> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-04tree-wide: s/struct fileattr/struct file_kattr/gChristian Brauner2-4/+4
Now that we expose struct file_attr as our uapi struct rename all the internal struct to struct file_kattr to clearly communicate that it is a kernel internal struct. This is similar to struct mount_{k}attr and others. Link: https://lore.kernel.org/20250703-restlaufzeit-baurecht-9ed44552b481@brauner Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-06-24fs: Remove three arguments from block_write_end()Matthew Wilcox (Oracle)1-3/+2
block_write_end() looks like it can be used as a ->write_end() implementation. However, it can't as it does not unlock nor put the folio. Since it does not use the 'file', 'mapping' nor 'fsdata' arguments, remove them. Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org> Link: https://lore.kernel.org/20250624132130.1590285-1-willy@infradead.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-06-23ext4: add FALLOC_FL_WRITE_ZEROES supportZhang Yi1-11/+55
Add support for FALLOC_FL_WRITE_ZEROES if the underlying device enable the unmap write zeroes operation. This first allocates blocks as unwritten, then issues a zero command outside of the running journal handle, and finally converts them to a written state. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://lore.kernel.org/20250619111806.3546162-10-yi.zhang@huaweicloud.com Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-06-17fs/ext4: transition from deprecated .mmap hook to .mmap_prepareLorenzo Stoakes1-6/+7
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"). Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Link: https://lore.kernel.org/5abfe526032a6698fd1bcd074a74165cda7ea57c.1750099179.git.lorenzo.stoakes@oracle.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-06-17fs/dax: make it possible to check dev dax support without a VMALorenzo Stoakes1-1/+1
This is a prerequisite for adapting those filesystems to use the .mmap_prepare() hook for mmap()'ing which invoke this check as this hook does not have access to a VMA pointer. To effect this, change the signature of daxdev_mapping_supported() and update its callers (ext4 and xfs mmap()'ing hook code). Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Link: https://lore.kernel.org/b09de1e8544384074165d92d048e80058d971286.1750099179.git.lorenzo.stoakes@oracle.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-06-08treewide, timers: Rename from_timer() to timer_container_of()timers-cleanups-2025-06-08Ingo Molnar1-1/+1
Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-05-28Merge tag 'ext4_for_linus-6.16-rc1' of ↵Linus Torvalds20-449/+1040
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "New ext4 features and performance improvements: - Fast commit performance improvements - Multi-fsblock atomic write support for bigalloc file systems - Large folio support for regular files This last can result in really stupendous performance for the right workloads. For example, see [1] where the Kernel Test Robot reported over 37% improvement on a large sequential I/O workload. There are also the usual bug fixes and cleanups. Of note are cleanups of the extent status tree to fix potential races that could result in the extent status tree getting corrupted under heavy simultaneous allocation and deallocation to a single file" Link: https://lore.kernel.org/all/202505161418.ec0d753f-lkp@intel.com/ [1] * tag 'ext4_for_linus-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (52 commits) ext4: Add a WARN_ON_ONCE for querying LAST_IN_LEAF instead ext4: Simplify flags in ext4_map_query_blocks() ext4: Rename and document EXT4_EX_FILTER to EXT4_EX_QUERY_FILTER ext4: Simplify last in leaf check in ext4_map_query_blocks ext4: Unwritten to written conversion requires EXT4_EX_NOCACHE ext4: only dirty folios when data journaling regular files ext4: Add atomic block write documentation ext4: Enable support for ext4 multi-fsblock atomic write using bigalloc ext4: Add multi-fsblock atomic write support with bigalloc ext4: Add support for EXT4_GET_BLOCKS_QUERY_LEAF_BLOCKS ext4: Make ext4_meta_trans_blocks() non-static for later use ext4: Check if inode uses extents in ext4_inode_can_atomic_write() ext4: Document an edge case for overwrites jbd2: remove journal_t argument from jbd2_superblock_csum() jbd2: remove journal_t argument from jbd2_chksum() ext4: remove sb argument from ext4_superblock_csum() ext4: remove sbi argument from ext4_chksum() ext4: enable large folio for regular file ext4: make online defragmentation support large folios ext4: make the writeback path support large folios ...
2025-05-26Merge tag 'xfs-merge-6.16' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds1-1/+1
Pull xfs updates from Carlos Maiolino: - Atomic writes for XFS - Remove experimental warnings for pNFS, scrub and parent pointers * tag 'xfs-merge-6.16' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (26 commits) xfs: add inode to zone caching for data placement xfs: free the item in xfs_mru_cache_insert on failure xfs: remove the EXPERIMENTAL warning for pNFS xfs: remove some EXPERIMENTAL warnings xfs: Remove deprecated xfs_bufd sysctl parameters xfs: stop using set_blocksize xfs: allow sysadmins to specify a maximum atomic write limit at mount time xfs: update atomic write limits xfs: add xfs_calc_atomic_write_unit_max() xfs: add xfs_file_dio_write_atomic() xfs: commit CoW-based atomic writes atomically xfs: add large atomic writes checks in xfs_direct_write_iomap_begin() xfs: add xfs_atomic_write_cow_iomap_begin() xfs: refine atomic write size check in xfs_file_write_iter() xfs: refactor xfs_reflink_end_cow_extent() xfs: allow block allocator to take an alignment hint xfs: ignore HW which cannot atomic write a single block xfs: add helpers to compute transaction reservation for finishing intent items xfs: add helpers to compute log item overhead xfs: separate out setting buftarg atomic writes limits ...
2025-05-20ext4: Add a WARN_ON_ONCE for querying LAST_IN_LEAF insteadRitesh Harjani (IBM)1-1/+3
We added the documentation in ext4_map_blocks() for usage of EXT4_GET_BLOCKS_QUERY_LAST_IN_LEAF flag. But It's better to add a WARN_ON_ONCE in case if anyone tries using this flag with CREATE to avoid a random issue later. Since depth can change with CREATE and it needs to be re-calculated before using it in there. Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Link: https://patch.msgid.link/ee6e82a224c50b432df9ce1ce3333c50182d8473.1747677758.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Simplify flags in ext4_map_query_blocks()Ritesh Harjani (IBM)2-4/+3
Now that we have EXT4_EX_QUERY_FILTER mask, let's use that to simplify the filtering of flags for passing to ext4_ext_map_blocks() in ext4_map_query_blocks() function. This allows us to kill the query_flags local variable which is not needed anymore. Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/4ae735e83e6f43341e53e2d289e59156a8360134.1747677758.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Rename and document EXT4_EX_FILTER to EXT4_EX_QUERY_FILTERRitesh Harjani (IBM)2-2/+7
Rename EXT4_EX_FILTER to EXT4_EX_QUERY_FILTER to better describe its purpose as a filter mask used specifically in ext4_map_query_blocks(). Add a comment explaining that this macro is used to filter flags needed when querying the on-disk extent tree. We will later use EXT4_EX_QUERY_FILTER mask to add another EXT4_GET_BLOCKS_QUERY needed to lookup in on-disk extent tree. Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/51f05d0ba286372eb8693af95bd4b10194b53141.1747677758.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Simplify last in leaf check in ext4_map_query_blocksRitesh Harjani (IBM)1-2/+1
This simplifies the check for last in leaf in ext4_map_query_blocks() and fixes this cocci warning. cocci warnings: (new ones prefixed by >>) >> fs/ext4/inode.c:573:49-51: WARNING !A || A && B is equivalent to !A || B Fixes: 5bb12b1837c0 ("ext4: Add support for EXT4_GET_BLOCKS_QUERY_LEAF_BLOCKS") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202505191524.auftmOwK-lkp@intel.com/ Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Link: https://patch.msgid.link/5fd5c806218c83f603c578c95997cf7f6da29d74.1747677758.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Unwritten to written conversion requires EXT4_EX_NOCACHERitesh Harjani (IBM)1-1/+1
This fixes the atomic write patch series after it was rebased on top of extent status cache cleanup series i.e. 'commit 402e38e6b71f57 ("ext4: prevent stale extent cache entries caused by concurrent I/O writeback")' After the above series, EXT4_GET_BLOCKS_IO_CONVERT_EXT flag which has EXT4_GET_BLOCKS_IO_SUBMIT flag set, requires that the io submit context of any kind should pass EXT4_EX_NOCACHE to avoid caching unncecessary extents in the extent status cache. This patch fixes that by adding the EXT4_EX_NOCACHE flag in ext4_convert_unwritten_extents_atomic() for unwritten to written conversion calls to ext4_map_blocks(). Fixes: b86629c2b299 ("ext4: Add multi-fsblock atomic write support with bigalloc") Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Link: https://patch.msgid.link/ea0ad9378ff6d31d73f4e53f87548e3a20817689.1747677758.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: only dirty folios when data journaling regular filesBrian Foster1-1/+6
fstest generic/388 occasionally reproduces a crash that looks as follows: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: <TASK> ext4_block_zero_page_range+0x30c/0x380 [ext4] ext4_truncate+0x436/0x440 [ext4] ext4_process_orphan+0x5d/0x110 [ext4] ext4_orphan_cleanup+0x124/0x4f0 [ext4] ext4_fill_super+0x262d/0x3110 [ext4] get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x26/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4ed/0x6b0 do_syscall_64+0x82/0x170 ... This occurs when processing a symlink inode from the orphan list. The partial block zeroing code in the truncate path calls ext4_dirty_journalled_data() -> folio_mark_dirty(). The latter calls mapping->a_ops->dirty_folio(), but symlink inodes are not assigned an a_ops vector in ext4, hence the crash. To avoid this problem, update the ext4_dirty_journalled_data() helper to only mark the folio dirty on regular files (for which a_ops is assigned). This also matches the journaling logic in the ext4_symlink() creation path, where ext4_handle_dirty_metadata() is called directly. Fixes: d84c9ebdac1e ("ext4: Mark pages with journalled data dirty") Signed-off-by: Brian Foster <bfoster@redhat.com> Link: https://patch.msgid.link/20250516173800.175577-1-bfoster@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org
2025-05-20ext4: Enable support for ext4 multi-fsblock atomic write using bigallocRitesh Harjani (IBM)1-2/+5
Last couple of patches added the needed support for multi-fsblock atomic writes using bigalloc. This patch ensures that filesystem advertizes the needed atomic write unit min and max values for enabling multi-fsblock atomic write support with bigalloc. Acked-by: Darrick J. Wong <djwong@kernel.org> Co-developed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/5e45d7ed24499024b9079436ba6698dae5298e29.1747337952.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Add multi-fsblock atomic write support with bigallocRitesh Harjani (IBM)4-5/+299
EXT4 supports bigalloc feature which allows the FS to work in size of clusters (group of blocks) rather than individual blocks. This patch adds atomic write support for bigalloc so that systems with bs = ps can also create FS using - mkfs.ext4 -F -O bigalloc -b 4096 -C 16384 <dev> With bigalloc ext4 can support multi-fsblock atomic writes. We will have to adjust ext4's atomic write unit max value to cluster size. This can then support atomic write of size anywhere between [blocksize, clustersize]. This patch adds the required changes to enable multi-fsblock atomic write support using bigalloc in the next patch. In this patch for block allocation: we first query the underlying region of the requested range by calling ext4_map_blocks() call. Here are the various cases which we then handle depending upon the underlying mapping type: 1. If the underlying region for the entire requested range is a mapped extent, then we don't call ext4_map_blocks() to allocate anything. We don't need to even start the jbd2 txn in this case. 2. For an append write case, we create a mapped extent. 3. If the underlying region is entirely a hole, then we create an unwritten extent for the requested range. 4. If the underlying region is a large unwritten extent, then we split the extent into 2 unwritten extent of required size. 5. If the underlying region has any type of mixed mapping, then we call ext4_map_blocks() in a loop to zero out the unwritten and the hole regions within the requested range. This then provide a single mapped extent type mapping for the requested range. Note: We invoke ext4_map_blocks() in a loop with the EXT4_GET_BLOCKS_ZERO flag only when the underlying extent mapping of the requested range is not entirely a hole, an unwritten extent, or a fully mapped extent. That is, if the underlying region contains a mix of hole(s), unwritten extent(s), and mapped extent(s), we use this loop to ensure that all the short mappings are zeroed out. This guarantees that the entire requested range becomes a single, uniformly mapped extent. It is ok to do so because we know this is being done on a bigalloc enabled filesystem where the block bitmap represents the entire cluster unit. Note having a single contiguous underlying region of type mapped, unwrittn or hole is not a problem. But the reason to avoid writing on top of mixed mapping region is because, atomic writes requires all or nothing should get written for the userspace pwritev2 request. So if at any point in time during the write if a crash or a sudden poweroff occurs, the region undergoing atomic write should read either complete old data or complete new data. But it should never have a mix of both old and new data. So, we first convert any mixed mapping region to a single contiguous mapped extent before any data gets written to it. This is because normally FS will only convert unwritten extents to written at the end of the write in ->end_io() call. And if we allow the writes over a mixed mapping and if a sudden power off happens in between, we will end up reading mix of new data (over mapped extents) and old data (over unwritten extents), because unwritten to written conversion never went through. So to avoid this and to avoid writes getting torned due to mixed mapping, we first allocate a single contiguous block mapping and then do the write. Acked-by: Darrick J. Wong <djwong@kernel.org> Co-developed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/c4965ac3407cbc773f0bc954d0966d9696f5038a.1747337952.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Add support for EXT4_GET_BLOCKS_QUERY_LEAF_BLOCKSRitesh Harjani (IBM)3-8/+112
There can be a case where there are contiguous extents on the adjacent leaf nodes of on-disk extent trees. So when someone tries to write to this contiguous range, ext4_map_blocks() call will split by returning 1 extent at a time if this is not already cached in extent_status tree cache (where if these extents when cached can get merged since they are contiguous). This is fine for a normal write however in case of atomic writes, it can't afford to break the write into two. Now this is also something that will only happen in the slow write case where we call ext4_map_blocks() for each of these extents spread across different leaf nodes. However, there is no guarantee that these extent status cache cannot be reclaimed before the last call to ext4_map_blocks() in ext4_map_blocks_atomic_write_slow(). Hence this patch adds support of EXT4_GET_BLOCKS_QUERY_LEAF_BLOCKS. This flag checks if the requested range can be fully found in extent status cache and return. If not, it looks up in on-disk extent tree via ext4_map_query_blocks(). If the found extent is the last entry in the leaf node, then it goes and queries the next lblk to see if there is an adjacent contiguous extent in the adjacent leaf node of the on-disk extent tree. Even though there can be a case where there are multiple adjacent extent entries spread across multiple leaf nodes. But we only read an adjacent leaf block i.e. in total of 2 extent entries spread across 2 leaf nodes. The reason for this is that we are mostly only going to support atomic writes with upto 64KB or maybe max upto 1MB of atomic write support. Acked-by: Darrick J. Wong <djwong@kernel.org> Co-developed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/6bb563e661f5fbd80e266a9e6ce6e29178f555f6.1747337952.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Make ext4_meta_trans_blocks() non-static for later useRitesh Harjani (IBM)2-5/+3
Let's make ext4_meta_trans_blocks() non-static for use in later functions during ->end_io conversion for atomic writes. We will need this function to estimate journal credits for a special case. Instead of adding another wrapper around it, let's make this non-static. Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/23ce80d4286f792831ce99d13558182ee228fedb.1747337952.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Check if inode uses extents in ext4_inode_can_atomic_write()Ritesh Harjani (IBM)1-1/+3
EXT4 only supports doing atomic write on inodes which uses extents, so add a check in ext4_inode_can_atomic_write() which gets called during open. Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/86bb502c979398a736ab371d8f35f6866a477f6c.1747337952.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: Document an edge case for overwritesRitesh Harjani (IBM)1-0/+4
ext4_iomap_overwrite_begin() clears the flag for IOMAP_WRITE before calling ext4_iomap_begin(). Document this above ext4_map_blocks() call as it is easy to miss it when focusing on write paths alone. Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/fd50ba05440042dff77d555e463a620a79f8d0e9.1747337952.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: remove sb argument from ext4_superblock_csum()Eric Biggers4-10/+8
Since ext4_superblock_csum() no longer uses its sb argument, remove it. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250513053809.699974-3-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: remove sbi argument from ext4_chksum()Eric Biggers12-55/+45
Since ext4_chksum() no longer uses its sbi argument, remove it. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250513053809.699974-2-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: enable large folio for regular fileZhang Yi4-1/+26
Besides fsverity, fscrypt, and the data=journal mode, ext4 now supports large folios for regular files. Enable this feature by default. However, since we cannot change the folio order limitation of mappings on active inodes, setting the journal=data mode via ioctl on an active inode will not take immediate effect in non-delalloc mode. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-9-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: make online defragmentation support large foliosZhang Yi1-7/+4
move_extent_per_page() currently assumes that each folio is the size of PAGE_SIZE and only copies data for one page. ext4_move_extents() should call move_extent_per_page() for each page. To support larger folios, simply modify the calculations for the block start and end offsets within the folio based on the provided range of 'data_offset_in_page' and 'block_len_in_page'. This function will continue to handle PAGE_SIZE of data at a time and will not convert this function to manage an entire folio. Additionally, we use the source folio to copy data, so it doesn't matter if the source and dest folios are different in size. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-8-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: make the writeback path support large foliosZhang Yi1-3/+3
In mpage_map_and_submit_buffers(), the 'lblk' is now aligned to PAGE_SIZE. Convert it to be aligned to folio size. Additionally, modify the wbc->nr_to_write update to reduce the number of pages in a single folio, ensuring that the entire writeback path can support large folios. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-7-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: correct the journal credits calculations of allocating blocksZhang Yi2-8/+7
The journal credits calculation in ext4_ext_index_trans_blocks() is currently inadequate. It only multiplies the depth of the extents tree and doesn't account for the blocks that may be required for adding the leaf extents themselves. After enabling large folios, we can easily run out of handle credits, triggering a warning in jbd2_journal_dirty_metadata() on filesystems with a 1KB block size. This occurs because we may need more extents when iterating through each large folio in ext4_do_writepages()->mpage_map_and_submit_extent(). Therefore, we should modify ext4_ext_index_trans_blocks() to include a count of the leaf extents in the worst case as well. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-6-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4/jbd2: convert jbd2_journal_blocks_per_page() to support large folioZhang Yi2-5/+5
jbd2_journal_blocks_per_page() returns the number of blocks in a single page. Rename it to jbd2_journal_blocks_per_folio() and make it returns the number of blocks in the largest folio, preparing for the calculation of journal credits blocks when allocating blocks within a large folio in the writeback path. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-5-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: make __ext4_block_zero_page_range() support large folioZhang Yi1-4/+3
The partial block zero range helper __ext4_block_zero_page_range() currently only supports folios of PAGE_SIZE in size. The calculations for the start block and the offset within a folio for the given range are incorrect. Modify the implementation to use offset_in_folio() instead of directly masking PAGE_SIZE - 1, which will be able to support for large folios. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-4-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: make regular file's buffered write path support large foliosZhang Yi1-10/+21
The current buffered write path in ext4 can only allocate and handle folios of PAGE_SIZE size. To support larger folios, modify ext4_da_write_begin() and ext4_write_begin() to allocate higher-order folios, and trim the write length if it exceeds the folio size. Additionally, in ext4_da_do_write_end(), use offset_in_folio() instead of PAGE_SIZE. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-3-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: make ext4_mpage_readpages() support large foliosZhang Yi1-11/+17
ext4_mpage_readpages() currently assumes that each folio is the size of PAGE_SIZE. Modify it to atomically calculate the number of blocks per folio and iterate through the blocks in each folio, which would allow for support of larger folios. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250512063319.3539411-2-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: ensure i_size is smaller than maxbytesZhang Yi1-1/+2
The inode i_size cannot be larger than maxbytes, check it while loading inode from the disk. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250506012009.3896990-4-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-05-20ext4: factor out ext4_get_maxbytes()Zhang Yi3-12/+9
There are several locations that get the correct maxbytes value based on the inode's block type. It would be beneficial to extract a common helper function to make the code more clear. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250506012009.3896990-3-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-05-20ext4: fix incorrect punch max_endZhang Yi1-3/+9
For the extents based inodes, the maxbytes should be sb->s_maxbytes instead of sbi->s_bitmap_maxbytes. Additionally, for the calculation of max_end, the -sb->s_blocksize operation is necessary only for indirect-block based inodes. Correct the maxbytes and max_end value to correct the behavior of punch hole. Fixes: 2da376228a24 ("ext4: limit length to bitmap_maxbytes - blocksize in punch_hole") Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250506012009.3896990-2-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-05-20ext4: fix out of bounds punch offsetZhang Yi1-1/+1
Punching a hole with a start offset that exceeds max_end is not permitted and will result in a negative length in the truncate_inode_partial_folio() function while truncating the page cache, potentially leading to undesirable consequences. A simple reproducer: truncate -s 9895604649994 /mnt/foo xfs_io -c "pwrite 8796093022208 4096" /mnt/foo xfs_io -c "fpunch 8796093022213 25769803777" /mnt/foo kernel BUG at include/linux/highmem.h:275! Oops: invalid opcode: 0000 [#1] SMP PTI CPU: 3 UID: 0 PID: 710 Comm: xfs_io Not tainted 6.15.0-rc3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:zero_user_segments.constprop.0+0xd7/0x110 RSP: 0018:ffffc90001cf3b38 EFLAGS: 00010287 RAX: 0000000000000005 RBX: ffffea0001485e40 RCX: 0000000000001000 RDX: 000000000040b000 RSI: 0000000000000005 RDI: 000000000040b000 RBP: 000000000040affb R08: ffff888000000000 R09: ffffea0000000000 R10: 0000000000000003 R11: 00000000fffc7fc5 R12: 0000000000000005 R13: 000000000040affb R14: ffffea0001485e40 R15: ffff888031cd3000 FS: 00007f4f63d0b780(0000) GS:ffff8880d337d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000001ae0b038 CR3: 00000000536aa000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> truncate_inode_partial_folio+0x3dd/0x620 truncate_inode_pages_range+0x226/0x720 ? bdev_getblk+0x52/0x3e0 ? ext4_get_group_desc+0x78/0x150 ? crc32c_arch+0xfd/0x180 ? __ext4_get_inode_loc+0x18c/0x840 ? ext4_inode_csum+0x117/0x160 ? jbd2_journal_dirty_metadata+0x61/0x390 ? __ext4_handle_dirty_metadata+0xa0/0x2b0 ? kmem_cache_free+0x90/0x5a0 ? jbd2_journal_stop+0x1d5/0x550 ? __ext4_journal_stop+0x49/0x100 truncate_pagecache_range+0x50/0x80 ext4_truncate_page_cache_block_range+0x57/0x3a0 ext4_punch_hole+0x1fe/0x670 ext4_fallocate+0x792/0x17d0 ? __count_memcg_events+0x175/0x2a0 vfs_fallocate+0x121/0x560 ksys_fallocate+0x51/0xc0 __x64_sys_fallocate+0x24/0x40 x64_sys_call+0x18d2/0x4170 do_syscall_64+0xa7/0x220 entry_SYSCALL_64_after_hwframe+0x76/0x7e Fix this by filtering out cases where the punching start offset exceeds max_end. Fixes: 982bf37da09d ("ext4: refactor ext4_punch_hole()") Reported-by: Liebes Wang <wanghaichi0403@gmail.com> Closes: https://lore.kernel.org/linux-ext4/ac3a58f6-e686-488b-a9ee-fc041024e43d@huawei.com/ Tested-by: Liebes Wang <wanghaichi0403@gmail.com> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250506012009.3896990-1-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-05-20ext4: use writeback_iter in ext4_journalled_submit_inode_data_buffersChristoph Hellwig1-24/+22
Use writeback_iter directly instead of write_cache_pages for a nicer code structure and less indirect calls. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250505091604.3449879-1-hch@lst.de Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-20ext4: fix calculation of credits for extent tree modificationJan Kara1-5/+6
Luis and David are reporting that after running generic/750 test for 90+ hours on 2k ext4 filesystem, they are able to trigger a warning in jbd2_journal_dirty_metadata() complaining that there are not enough credits in the running transaction started in ext4_do_writepages(). Indeed the code in ext4_do_writepages() is racy and the extent tree can change between the time we compute credits necessary for extent tree computation and the time we actually modify the extent tree. Thus it may happen that the number of credits actually needed is higher. Modify ext4_ext_index_trans_blocks() to count with the worst case of maximum tree depth. This can reduce the possible number of writers that can operate in the system in parallel (because the credit estimates now won't fit in one transaction) but for reasonably sized journals this shouldn't really be an issue. So just go with a safe and simple fix. Link: https://lore.kernel.org/all/20250415013641.f2ppw6wov4kn4wq2@offworld Reported-by: Davidlohr Bueso <dave@stgolabs.net> Reported-by: Luis Chamberlain <mcgrof@kernel.org> Tested-by: kdevops@lists.linux.dev Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250429175535.23125-2-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2025-05-16ext4: avoid -Wformat-security warningArnd Bergmann1-1/+1
check_igot_inode() prints a variable string, which causes a harmless warning with 'make W=1': fs/ext4/inode.c:4763:45: error: format string is not a string literal (potentially insecure) [-Werror,-Wformat-security] 4763 | ext4_error_inode(inode, function, line, 0, err_str); Use a trivial "%s" format string instead. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250423164354.2780635-1-arnd@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-15ext4: clairfy the rules for modifying extentsZhang Yi1-2/+33
Add a comment at the beginning of extents_status.c to clarify the rules for loading, mapping, modifying, and removing extents and blocks. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-10-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-15ext4: check env when mapping and modifying extentsZhang Yi2-3/+16
Add ext4_check_map_extents_env() to the places where loading extents, mapping blocks, removing blocks, and modifying extents, excluding the I/O writeback context. This function will verify whether the locking mechanisms in place are adequate. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-9-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-14ext4: introduce ext4_check_map_extents_env() debug helperZhang Yi2-0/+27
Loading and modifying the extents tree and extent status tree without holding the inode's i_rwsem or the mapping's invalidate_lock is not permitted, except during the I/O writeback. Add a new debug helper ext4_check_map_extents_env(), it will verify whether the extent loading/modifying context is safe. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-8-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-14ext4: factor out is_special_ino()Zhang Yi2-6/+12
Factor out the helper is_special_ino() to facilitate the checking of special inodes in the subsequent patches. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-7-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-14ext4: prevent stale extent cache entries caused by concurrent get es_cacheZhang Yi2-1/+9
The EXT4_IOC_GET_ES_CACHE and EXT4_IOC_PRECACHE_EXTENTS currently invokes ext4_ext_precache() to preload the extent cache without holding the inode's i_rwsem. This can result in stale extent cache entries when competing with operations such as ext4_collapse_range() which calls ext4_ext_remove_space() or ext4_ext_shift_extents(). The problem arises when ext4_ext_remove_space() temporarily releases i_data_sem due to insufficient journal credits. During this interval, a concurrent EXT4_IOC_GET_ES_CACHE or EXT4_IOC_PRECACHE_EXTENTS may cache extent entries that are about to be deleted. As a result, these cached entries become stale and inconsistent with the actual extents. Loading the extents cache without holding the inode's i_rwsem or the mapping's invalidate_lock is not permitted besides during the writeback. Fix this by holding the i_rwsem during EXT4_IOC_GET_ES_CACHE and EXT4_IOC_PRECACHE_EXTENTS. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-6-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-14ext4: prevent stale extent cache entries caused by concurrent fiemapZhang Yi1-6/+11
The ext4_fiemap() currently invokes ext4_ext_precache() and iomap_fiemap() to preload the extent cache and query mapping information without holding the inode's i_rwsem. This can result in stale extent cache entries when competing with operations such as ext4_collapse_range() which calls ext4_ext_remove_space() or ext4_ext_shift_extents(). The problem arises when ext4_ext_remove_space() temporarily releases i_data_sem due to insufficient journal credits. During this interval, a concurrent ext4_fiemap() may cache extent entries that are about to be deleted. As a result, these cached entries become stale and inconsistent with the actual extents. Loading the extents cache without holding the inode's i_rwsem or the mapping's invalidate_lock is not permitted besides during the writeback. Fix this by holding the i_rwsem in ext4_fiemap(). Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-5-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-14ext4: prevent stale extent cache entries caused by concurrent I/O writebackZhang Yi4-12/+32
Currently, in the I/O writeback path, ext4_map_blocks() may attempt to cache additional unrelated extents in the extent status tree without holding the inode's i_rwsem and the mapping's invalidate_lock. This can lead to stale extent status entries remaining in certain scenarios, potentially causing data corruption. For example, when performing a collapse range in ext4_collapse_range(), it clears the extent cache and dirty pages before removing blocks and shifting extents. It also holds the i_data_sem during these two operations. However, both ext4_ext_remove_space() and ext4_ext_shift_extents() may briefly release the i_data_sem if journal credits are insufficient (ext4_datasem_ensure_credits()). If another writeback process writes dirty pages from other regions during this interval, it may cache extents that are about to be modified. Unless ext4_collapse_range() explicitly clears the extent cache again, these cached entries can become stale and inconsistent with the actual extents. 0 a n b c m | | | | | | [www][wwwwww][wwwwwwww]...[wwwww][wwww]... | | N M Assume that block a is dirty. The collapse range operation is removing data from n to m and drops i_data_sem immediately after removing the extent from b to c. At the same time, a concurrent writeback begins to write back block a; it will reloads the extent from [n, b) into the extent status tree since it does not hold the i_rwsem or the invalidate_lock. After the collapse range operation, it left the stale extent [n, b), which points logical block n to N, but the actual physical block of n should be M. Similarly, both ext4_insert_range() and ext4_truncate() have the same problem. ext4_punch_hole() survived since it re-add a hole extent entry after removing space since commit 9f1118223aa0 ("ext4: add a hole extent entry in cache after punch"). In most cases, during dirty page writeback, the block mapping information is likely to be found in the extent cache, making it less necessary to search for physical extents. Consequently, loading unrelated extent caches during writeback appears to be ineffective. Therefore, fix this by adds EXT4_EX_NOCACHE in the writeback path to prevent caching of unrelated extents, eliminating this potential source of corruption. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-4-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-14ext4: generalize EXT4_GET_BLOCKS_IO_SUBMIT flag usageZhang Yi2-6/+10
Currently, the EXT4_GET_BLOCKS_IO_SUBMIT flag is only used during data writeback to indicate that in ordered mode, the journal commit thread should skip re-submitting data and simply wait for I/O completion. To prepare for later patches that need to detect I/O submission context in ext4_map_blocks(), generalizes the meaning of EXT4_GET_BLOCKS_IO_SUBMIT. This flag will be set during: 1) data I/O writeback, 2) I/O completion extents conversion, 3) journal performing commit in fast_commit. This change doesn't affect current usage of this flag and provides a clear way to identify I/O submission context. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-3-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-14ext4: ext4: unify EXT4_EX_NOCACHE|NOFAIL flags in ext4_ext_remove_space()Zhang Yi1-9/+10
When removing space, we should use EXT4_EX_NOCACHE because we don't need to cache extents, and we should also use EXT4_EX_NOFAIL to prevent metadata inconsistencies that may arise from memory allocation failures. While ext4_ext_remove_space() already uses these two flags in most places, they are missing in ext4_ext_search_right() and read_extent_tree_block() calls. Unify the flags to ensure consistent behavior throughout the extent removal process. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20250423085257.122685-2-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-13ext4: inline: fix len overflow in ext4_prepare_inline_dataThadeu Lima de Souza Cascardo1-1/+1
When running the following code on an ext4 filesystem with inline_data feature enabled, it will lead to the bug below. fd = open("file1", O_RDWR | O_CREAT | O_TRUNC, 0666); ftruncate(fd, 30); pwrite(fd, "a", 1, (1UL << 40) + 5UL); That happens because write_begin will succeed as when ext4_generic_write_inline_data calls ext4_prepare_inline_data, pos + len will be truncated, leading to ext4_prepare_inline_data parameter to be 6 instead of 0x10000000006. Then, later when write_end is called, we hit: BUG_ON(pos + len > EXT4_I(inode)->i_inline_size); at ext4_write_inline_data. Fix it by using a loff_t type for the len parameter in ext4_prepare_inline_data instead of an unsigned int. [ 44.545164] ------------[ cut here ]------------ [ 44.545530] kernel BUG at fs/ext4/inline.c:240! [ 44.545834] Oops: invalid opcode: 0000 [#1] SMP NOPTI [ 44.546172] CPU: 3 UID: 0 PID: 343 Comm: test Not tainted 6.15.0-rc2-00003-g9080916f4863 #45 PREEMPT(full) 112853fcebfdb93254270a7959841d2c6aa2c8bb [ 44.546523] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 44.546523] RIP: 0010:ext4_write_inline_data+0xfe/0x100 [ 44.546523] Code: 3c 0e 48 83 c7 48 48 89 de 5b 41 5c 41 5d 41 5e 41 5f 5d e9 e4 fa 43 01 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 0f 0b <0f> 0b 0f 1f 44 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 20 49 [ 44.546523] RSP: 0018:ffffb342008b79a8 EFLAGS: 00010216 [ 44.546523] RAX: 0000000000000001 RBX: ffff9329c579c000 RCX: 0000010000000006 [ 44.546523] RDX: 000000000000003c RSI: ffffb342008b79f0 RDI: ffff9329c158e738 [ 44.546523] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 [ 44.546523] R10: 00007ffffffff000 R11: ffffffff9bd0d910 R12: 0000006210000000 [ 44.546523] R13: fffffc7e4015e700 R14: 0000010000000005 R15: ffff9329c158e738 [ 44.546523] FS: 00007f4299934740(0000) GS:ffff932a60179000(0000) knlGS:0000000000000000 [ 44.546523] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 44.546523] CR2: 00007f4299a1ec90 CR3: 0000000002886002 CR4: 0000000000770eb0 [ 44.546523] PKRU: 55555554 [ 44.546523] Call Trace: [ 44.546523] <TASK> [ 44.546523] ext4_write_inline_data_end+0x126/0x2d0 [ 44.546523] generic_perform_write+0x17e/0x270 [ 44.546523] ext4_buffered_write_iter+0xc8/0x170 [ 44.546523] vfs_write+0x2be/0x3e0 [ 44.546523] __x64_sys_pwrite64+0x6d/0xc0 [ 44.546523] do_syscall_64+0x6a/0xf0 [ 44.546523] ? __wake_up+0x89/0xb0 [ 44.546523] ? xas_find+0x72/0x1c0 [ 44.546523] ? next_uptodate_folio+0x317/0x330 [ 44.546523] ? set_pte_range+0x1a6/0x270 [ 44.546523] ? filemap_map_pages+0x6ee/0x840 [ 44.546523] ? ext4_setattr+0x2fa/0x750 [ 44.546523] ? do_pte_missing+0x128/0xf70 [ 44.546523] ? security_inode_post_setattr+0x3e/0xd0 [ 44.546523] ? ___pte_offset_map+0x19/0x100 [ 44.546523] ? handle_mm_fault+0x721/0xa10 [ 44.546523] ? do_user_addr_fault+0x197/0x730 [ 44.546523] ? do_syscall_64+0x76/0xf0 [ 44.546523] ? arch_exit_to_user_mode_prepare+0x1e/0x60 [ 44.546523] ? irqentry_exit_to_user_mode+0x79/0x90 [ 44.546523] entry_SYSCALL_64_after_hwframe+0x55/0x5d [ 44.546523] RIP: 0033:0x7f42999c6687 [ 44.546523] Code: 48 89 fa 4c 89 df e8 58 b3 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff [ 44.546523] RSP: 002b:00007ffeae4a7930 EFLAGS: 00000202 ORIG_RAX: 0000000000000012 [ 44.546523] RAX: ffffffffffffffda RBX: 00007f4299934740 RCX: 00007f42999c6687 [ 44.546523] RDX: 0000000000000001 RSI: 000055ea6149200f RDI: 0000000000000003 [ 44.546523] RBP: 00007ffeae4a79a0 R08: 0000000000000000 R09: 0000000000000000 [ 44.546523] R10: 0000010000000005 R11: 0000000000000202 R12: 0000000000000000 [ 44.546523] R13: 00007ffeae4a7ac8 R14: 00007f4299b86000 R15: 000055ea61493dd8 [ 44.546523] </TASK> [ 44.546523] Modules linked in: [ 44.568501] ---[ end trace 0000000000000000 ]--- [ 44.568889] RIP: 0010:ext4_write_inline_data+0xfe/0x100 [ 44.569328] Code: 3c 0e 48 83 c7 48 48 89 de 5b 41 5c 41 5d 41 5e 41 5f 5d e9 e4 fa 43 01 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 0f 0b <0f> 0b 0f 1f 44 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 20 49 [ 44.570931] RSP: 0018:ffffb342008b79a8 EFLAGS: 00010216 [ 44.571356] RAX: 0000000000000001 RBX: ffff9329c579c000 RCX: 0000010000000006 [ 44.571959] RDX: 000000000000003c RSI: ffffb342008b79f0 RDI: ffff9329c158e738 [ 44.572571] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 [ 44.573148] R10: 00007ffffffff000 R11: ffffffff9bd0d910 R12: 0000006210000000 [ 44.573748] R13: fffffc7e4015e700 R14: 0000010000000005 R15: ffff9329c158e738 [ 44.574335] FS: 00007f4299934740(0000) GS:ffff932a60179000(0000) knlGS:0000000000000000 [ 44.575027] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 44.575520] CR2: 00007f4299a1ec90 CR3: 0000000002886002 CR4: 0000000000770eb0 [ 44.576112] PKRU: 55555554 [ 44.576338] Kernel panic - not syncing: Fatal exception [ 44.576517] Kernel Offset: 0x1a600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) Reported-by: syzbot+fe2a25dae02a207717a0@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=fe2a25dae02a207717a0 Fixes: f19d5870cbf7 ("ext4: add normal write support for inline data") Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com> Cc: stable@vger.kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://patch.msgid.link/20250415-ext4-prepare-inline-overflow-v1-1-f4c13d900967@igalia.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>