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2026-04-18Merge tag 'ext4_for_linux-7.0-rc1' of ↵Linus Torvalds1-65/+24
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: - Refactor code paths involved with partial block zero-out in prearation for converting ext4 to use iomap for buffered writes - Remove use of d_alloc() from ext4 in preparation for the deprecation of this interface - Replace some J_ASSERTS with a journal abort so we can avoid a kernel panic for a localized file system error - Simplify various code paths in mballoc, move_extent, and fast commit - Fix rare deadlock in jbd2_journal_cancel_revoke() that can be triggered by generic/013 when blocksize < pagesize - Fix memory leak when releasing an extended attribute when its value is stored in an ea_inode - Fix various potential kunit test bugs in fs/ext4/extents.c - Fix potential out-of-bounds access in check_xattr() with a corrupted file system - Make the jbd2_inode dirty range tracking safe for lockless reads - Avoid a WARN_ON when writeback files due to a corrupted file system; we already print an ext4 warning indicatign that data will be lost, so the WARN_ON is not necessary and doesn't add any new information * tag 'ext4_for_linux-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (37 commits) jbd2: fix deadlock in jbd2_journal_cancel_revoke() ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all() ext4: fix possible null-ptr-deref in mbt_kunit_exit() ext4: fix possible null-ptr-deref in extents_kunit_exit() ext4: fix the error handling process in extents_kunit_init). ext4: call deactivate_super() in extents_kunit_exit() ext4: fix miss unlock 'sb->s_umount' in extents_kunit_init() ext4: fix bounds check in check_xattrs() to prevent out-of-bounds access ext4: zero post-EOF partial block before appending write ext4: move pagecache_isize_extended() out of active handle ext4: remove ctime/mtime update from ext4_alloc_file_blocks() ext4: unify SYNC mode checks in fallocate paths ext4: ensure zeroed partial blocks are persisted in SYNC mode ext4: move zero partial block range functions out of active handle ext4: pass allocate range as loff_t to ext4_alloc_file_blocks() ext4: remove handle parameters from zero partial block functions ext4: move ordered data handling out of ext4_block_do_zero_range() ext4: rename ext4_block_zero_page_range() to ext4_block_zero_range() ext4: factor out journalled block zeroing range ext4: rename and extend ext4_block_truncate_page() ...
2026-04-13Merge tag 'vfs-7.1-rc1.kino' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs i_ino updates from Christian Brauner: "For historical reasons, the inode->i_ino field is an unsigned long, which means that it's 32 bits on 32 bit architectures. This has caused a number of filesystems to implement hacks to hash a 64-bit identifier into a 32-bit field, and deprives us of a universal identifier field for an inode. This changes the inode->i_ino field from an unsigned long to a u64. This shouldn't make any material difference on 64-bit hosts, but 32-bit hosts will see struct inode grow by at least 4 bytes. This could have effects on slabcache sizes and field alignment. The bulk of the changes are to format strings and tracepoints, since the kernel itself doesn't care that much about the i_ino field. The first patch changes some vfs function arguments, so check that one out carefully. With this change, we may be able to shrink some inode structures. For instance, struct nfs_inode has a fileid field that holds the 64-bit inode number. With this set of changes, that field could be eliminated. I'd rather leave that sort of cleanups for later just to keep this simple" * tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group() EVM: add comment describing why ino field is still unsigned long vfs: remove externs from fs.h on functions modified by i_ino widening treewide: fix missed i_ino format specifier conversions ext4: fix signed format specifier in ext4_load_inode trace event treewide: change inode->i_ino from unsigned long to u64 nilfs2: widen trace event i_ino fields to u64 f2fs: widen trace event i_ino fields to u64 ext4: widen trace event i_ino fields to u64 zonefs: widen trace event i_ino fields to u64 hugetlbfs: widen trace event i_ino fields to u64 ext2: widen trace event i_ino fields to u64 cachefiles: widen trace event i_ino fields to u64 vfs: widen trace event i_ino fields to u64 net: change sock.sk_ino and sock_i_ino() to u64 audit: widen ino fields to u64 vfs: widen inode hash/lookup functions to u64
2026-04-10ext4: move dcache manipulation out of __ext4_link()NeilBrown1-28/+4
__ext4_link() has two callers. - ext4_link() calls it during normal handling of the link() system call or similar - ext4_fc_replay_link_internal() calls it when replaying the journal at mount time. The former needs changes to dcache - instantiating the dentry to the inode on success. The latter doesn't need or want any dcache manipulation. So move the manipulation out of __ext4_link() and do it in ext4_link() only. This requires: - passing the qname from the dentry explicitly to __ext4_link. The parent dir is already passed. The dentry is still passed in the ext4_link() case purely for use by ext4_fc_track_link(). - passing the inode separately to ext4_fc_track_link() as the dentry will not be instantiated yet. - using __ext4_add_entry() in ext4_link, which doesn't need a dentry. - moving ihold(), d_instantiate(), drop_nlink() and iput() calls out of __ext4_link() into ext4_link(). Note that ext4_inc_count() and drop_nlink() remain in __ext4_link() as both callers need them and they are not related to the dentry. This substantially simplifies ext4_fc_replay_link_internal(), and removes a use of d_alloc() which, it is planned, will be removed. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260320000838.3797494-4-neilb@ownmail.net Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-10ext4: add ext4_fc_eligible()NeilBrown1-29/+14
Testing EXT4_MF_FC_INELIGIBLE is almost always combined with testing ext4_fc_disabled(). The code can be simplified by combining these two in a new ext4_fc_eligible(). In ext4_fc_track_inode() this moves the ext4_fc_disabled() test after ext4_fc_mark_ineligible(), but as that is a non-op when ext4_fc_disabled() is true, this is no no consequence. Note that it is important to still call ext4_fc_mark_ineligible() in ext4_fc_track_inode() even when ext4_fc_eligible() would return true. ext4_fc_mark_ineligible() does not ONLY set the "INELIGIBLE" flag but also updates ->s_fc_ineligible_tid to make sure that the flag remains set until all ineligible transactions have been committed. Reviewed-by: Andreas Dilger <adilger@dilger.ca> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260320000838.3797494-3-neilb@ownmail.net Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-10ext4: prefer IS_ERR_OR_NULL over manual NULL checkPhilipp Hahn1-1/+1
Prefer using IS_ERR_OR_NULL() over using IS_ERR() and a manual NULL check. Change generated with coccinelle. To: "Theodore Ts'o" <tytso@mit.edu> To: Andreas Dilger <adilger.kernel@dilger.ca> Cc: linux-ext4@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Philipp Hahn <phahn-oss@avm.de> Link: https://patch.msgid.link/20260310-b4-is_err_or_null-v1-4-bd63b656022d@avm.de Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09ext4: remove tl argument from ext4_fc_replay_{add,del}_rangeGuoqing Jiang1-6/+4
Since commit a7ba36bc94f2 ("ext4: fix fast commit alignment issues"), both ext4_fc_replay_add_range and ext4_fc_replay_del_range get ex based on 'val' instead of 'tl'. Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20260121063805.19863-1-guoqing.jiang@linux.dev Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09ext4: remove unused i_fc_waitLi Chen1-1/+1
i_fc_wait is only initialized in ext4_fc_init_inode() and never used for waiting or wakeups. Drop it. Signed-off-by: Li Chen <me@linux.beauty> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Link: https://patch.msgid.link/20260120121941.144192-1-me@linux.beauty Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-03-28ext4: fix iloc.bh leak in ext4_fc_replay_inode() error pathsBaokun Li1-5/+8
During code review, Joseph found that ext4_fc_replay_inode() calls ext4_get_fc_inode_loc() to get the inode location, which holds a reference to iloc.bh that must be released via brelse(). However, several error paths jump to the 'out' label without releasing iloc.bh: - ext4_handle_dirty_metadata() failure - sync_dirty_buffer() failure - ext4_mark_inode_used() failure - ext4_iget() failure Fix this by introducing an 'out_brelse' label placed just before the existing 'out' label to ensure iloc.bh is always released. Additionally, make ext4_fc_replay_inode() propagate errors properly instead of always returning 0. Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com> Fixes: 8016e29f4362 ("ext4: fast commit recovery path") Signed-off-by: Baokun Li <libaokun@linux.alibaba.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20260323060836.3452660-1-libaokun@linux.alibaba.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2026-03-28ext4: publish jinode after initializationLi Chen1-2/+2
ext4_inode_attach_jinode() publishes ei->jinode to concurrent users. It used to set ei->jinode before jbd2_journal_init_jbd_inode(), allowing a reader to observe a non-NULL jinode with i_vfs_inode still unset. The fast commit flush path can then pass this jinode to jbd2_wait_inode_data(), which dereferences i_vfs_inode->i_mapping and may crash. Below is the crash I observe: ``` BUG: unable to handle page fault for address: 000000010beb47f4 PGD 110e51067 P4D 110e51067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 1 UID: 0 PID: 4850 Comm: fc_fsync_bench_ Not tainted 6.18.0-00764-g795a690c06a5 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.17.0-2-2 04/01/2014 RIP: 0010:xas_find_marked+0x3d/0x2e0 Code: e0 03 48 83 f8 02 0f 84 f0 01 00 00 48 8b 47 08 48 89 c3 48 39 c6 0f 82 fd 01 00 00 48 85 c9 74 3d 48 83 f9 03 77 63 4c 8b 0f <49> 8b 71 08 48 c7 47 18 00 00 00 00 48 89 f1 83 e1 03 48 83 f9 02 RSP: 0018:ffffbbee806e7bf0 EFLAGS: 00010246 RAX: 000000000010beb4 RBX: 000000000010beb4 RCX: 0000000000000003 RDX: 0000000000000001 RSI: 0000002000300000 RDI: ffffbbee806e7c10 RBP: 0000000000000001 R08: 0000002000300000 R09: 000000010beb47ec R10: ffff9ea494590090 R11: 0000000000000000 R12: 0000002000300000 R13: ffffbbee806e7c90 R14: ffff9ea494513788 R15: ffffbbee806e7c88 FS: 00007fc2f9e3e6c0(0000) GS:ffff9ea6b1444000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000010beb47f4 CR3: 0000000119ac5000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> filemap_get_folios_tag+0x87/0x2a0 __filemap_fdatawait_range+0x5f/0xd0 ? srso_alias_return_thunk+0x5/0xfbef5 ? __schedule+0x3e7/0x10c0 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? preempt_count_sub+0x5f/0x80 ? srso_alias_return_thunk+0x5/0xfbef5 ? cap_safe_nice+0x37/0x70 ? srso_alias_return_thunk+0x5/0xfbef5 ? preempt_count_sub+0x5f/0x80 ? srso_alias_return_thunk+0x5/0xfbef5 filemap_fdatawait_range_keep_errors+0x12/0x40 ext4_fc_commit+0x697/0x8b0 ? ext4_file_write_iter+0x64b/0x950 ? srso_alias_return_thunk+0x5/0xfbef5 ? preempt_count_sub+0x5f/0x80 ? srso_alias_return_thunk+0x5/0xfbef5 ? vfs_write+0x356/0x480 ? srso_alias_return_thunk+0x5/0xfbef5 ? preempt_count_sub+0x5f/0x80 ext4_sync_file+0xf7/0x370 do_fsync+0x3b/0x80 ? syscall_trace_enter+0x108/0x1d0 __x64_sys_fdatasync+0x16/0x20 do_syscall_64+0x62/0x2c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ... ``` Fix this by initializing the jbd2_inode first. Use smp_wmb() and WRITE_ONCE() to publish ei->jinode after initialization. Readers use READ_ONCE() to fetch the pointer. Fixes: a361293f5fede ("jbd2: Fix oops in jbd2_journal_file_inode()") Cc: stable@vger.kernel.org Signed-off-by: Li Chen <me@linux.beauty> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20260225082617.147957-1-me@linux.beauty Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2026-03-06treewide: change inode->i_ino from unsigned long to u64Jeff Layton1-4/+4
On 32-bit architectures, unsigned long is only 32 bits wide, which causes 64-bit inode numbers to be silently truncated. Several filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that exceed 32 bits, and this truncation can lead to inode number collisions and other subtle bugs on 32-bit systems. Change the type of inode->i_ino from unsigned long to u64 to ensure that inode numbers are always represented as 64-bit values regardless of architecture. Update all format specifiers treewide from %lu/%lx to %llu/%llx to match the new type, along with corresponding local variable types. This is the bulk treewide conversion. Earlier patches in this series handled trace events separately to allow trace field reordering for better struct packing on 32-bit. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-20ext4: fast commit: make s_fc_lock reclaim-safeLi Chen1-23/+28
s_fc_lock can be acquired from inode eviction and thus is reclaim unsafe. Since the fast commit path holds s_fc_lock while writing the commit log, allocations under the lock can enter reclaim and invert the lock order with fs_reclaim. Add ext4_fc_lock()/ext4_fc_unlock() helpers which acquire s_fc_lock under memalloc_nofs_save()/restore() context and use them everywhere so allocations under the lock cannot recurse into filesystem reclaim. Fixes: 6593714d67ba ("ext4: hold s_fc_lock while during fast commit") Signed-off-by: Li Chen <me@linux.beauty> Reviewed-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/20260106120621.440126-1-me@linux.beauty Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-01-20ext4: mark move extents fast-commit ineligibleLi Chen1-0/+1
Fast commits only log operations that have dedicated replay support. EXT4_IOC_MOVE_EXT swaps extents between regular files and may copy data, rewriting the affected inodes' block mapping layout without going through the fast commit tracking paths. In practice these operations are rare and usually followed by further updates, but mixing them into a fast commit makes the overall semantics harder to reason about and risks replay gaps if new call sites appear. Teach ext4 to mark the filesystem fast-commit ineligible for the journal transactions used by move_extent_per_page() when EXT4_IOC_MOVE_EXT runs. This forces those transactions to fall back to a full commit, ensuring that these multi-inode extent swaps are captured by the normal journal rather than partially encoded in fast commit TLVs. This change should not affect common workloads but makes online defragmentation safer and easier to reason about under fast commit. Testing: 1. prepare: dd if=/dev/zero of=/root/fc_move.img bs=1M count=0 seek=256 mkfs.ext4 -O fast_commit -F /root/fc_move.img mkdir -p /mnt/fc_move && mount -t ext4 -o loop \ /root/fc_move.img /mnt/fc_move 2. Created two files, ran EXT4_IOC_MOVE_EXT via e4defrag, and checked the ineligible reason statistics: fallocate -l 64M /mnt/fc_move/file1 cp /mnt/fc_move/file1 /mnt/fc_move/file2 e4defrag /mnt/fc_move/file1 cat /proc/fs/ext4/loop0/fc_info shows "Move extents": > 0 and fc stats ineligible > 0. Signed-off-by: Li Chen <me@linux.beauty> Link: https://patch.msgid.link/20251211115146.897420-4-me@linux.beauty Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-01-20ext4: mark fs-verity enable fast-commit ineligibleLi Chen1-0/+1
Fast commits only log operations that have dedicated replay support. Enabling fs-verity builds a Merkle tree and updates inode and orphan state in ways that are not described by the fast commit replay tags. In practice these operations are rare and usually followed by further updates, but mixing them into a fast commit makes the overall semantics harder to reason about and risks replay gaps if new call sites appear. Teach ext4 to mark the filesystem fast-commit ineligible when ext4_end_enable_verity() starts its journal transaction. This forces that transaction to fall back to a full commit, ensuring that the fs-verity enable changes are captured by the normal journal rather than partially encoded in fast commit TLVs. This change should not affect common workloads but makes fs-verity enable safer and easier to reason about under fast commit. Testing: 1. prepare: dd if=/dev/zero of=/root/fc_verity.img bs=1M count=0 seek=128 mkfs.ext4 -O fast_commit,verity -F /root/fc_verity.img mkdir -p /mnt/fc_verity && mount -t ext4 -o loop /root/fc_verity.img /mnt/fc_verity 2. Enabled fs-verity on a file and verified reason accounting: echo "data" > /mnt/fc_verity/verityfile /root/enable_verity /mnt/fc_verity/verityfile sync tail -n 1 /proc/fs/ext4/loop0/fc_info "fs-verity enable": 1 3. Enabled fs-verity on a second file, fsynced it, and checked that the ineligible commit counter is updated too: echo "data2" > /mnt/fc_verity/verityfile2 /root/enable_verity /mnt/fc_verity/verityfile2 /root/fsync_file /mnt/fc_verity/verityfile2 sync /proc/fs/ext4/loop0/fc_info shows "fs-verity enable" incremented and fc stats ineligible increased accordingly. Signed-off-by: Li Chen <me@linux.beauty> Link: https://patch.msgid.link/20251211115146.897420-3-me@linux.beauty Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-01-20ext4: mark inode format migration fast-commit ineligibleLi Chen1-0/+1
Fast commits only log operations that have dedicated replay support. Inode format migration (indirect<->extent layout changes via EXT4_IOC_MIGRATE or toggling EXT4_EXTENTS_FL) rewrites the block mapping representation without going through the fast commit tracking paths. In practice these migrations are rare and usually followed by further updates, but mixing them into a fast commit makes the overall semantics harder to reason about and risks replay gaps if new call sites appear. Teach ext4 to mark the filesystem fast-commit ineligible when ext4_ext_migrate() or ext4_ind_migrate() start their journal transactions. This forces those transactions to fall back to a full commit, ensuring that the entire inode layout change is captured by the normal journal rather than partially encoded in fast commit TLVs. This change should not affect common workloads but makes format migrations safer and easier to reason about under fast commit. Testing: 1. prepare: dd if=/dev/zero of=/root/fc.img bs=1M count=0 seek=128 mkfs.ext4 -O fast_commit -F /root/fc.img mkdir -p /mnt/fc && mount -t ext4 -o loop /root/fc.img /mnt/fc 2. Created a test file and toggled the extents flag to exercise both ext4_ind_migrate() and ext4_ext_migrate(): touch /mnt/fc/migtest chattr -e /mnt/fc/migtest chattr +e /mnt/fc/migtest 3. Verified fast-commit ineligible statistics: tail -n 1 /proc/fs/ext4/loop0/fc_info "Inode format migration": 2 Signed-off-by: Li Chen <me@linux.beauty> Link: https://patch.msgid.link/20251211115146.897420-2-me@linux.beauty 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>
2025-05-20ext4: remove sbi argument from ext4_chksum()Eric Biggers1-5/+5
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>
2025-05-14ext4: prevent stale extent cache entries caused by concurrent I/O writebackZhang Yi1-1/+2
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 Yi1-1/+2
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>
2025-05-09ext4: hold s_fc_lock while during fast commitHarshad Shirwadkar1-31/+13
Leaving s_fc_lock in between during commit in ext4_fc_perform_commit() function leaves room for subtle concurrency bugs where ext4_fc_del() may delete an inode from the fast commit list, leaving list in an inconsistent state. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250508175908.1004880-10-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-09ext4: convert s_fc_lock to mutex typeHarshad Shirwadkar1-30/+30
This allows us to hold s_fc_lock during kmem_cache_* functions, which is needed in the following patch. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250508175908.1004880-9-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-09ext4: temporarily elevate commit thread priorityHarshad Shirwadkar1-0/+13
Unlike JBD2 based full commits, there is no dedicated journal thread for fast commits. Thus to reduce scheduling delays between IO submission and completion, temporarily elevate the committer thread's priority to match the configured priority of the JBD2 journal thread. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250508175908.1004880-8-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-09ext4: update code documentationHarshad Shirwadkar1-17/+31
This patch updates code documentation to reflect the commit path changes made in this series. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> code docs Link: https://patch.msgid.link/20250508175908.1004880-7-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-09ext4: drop i_fc_updates from inode fc infoHarshad Shirwadkar1-68/+0
The new logic introduced in this series does not require tracking number of active handles open on an inode. So, drop it. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20250508175908.1004880-6-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-09ext4: rework fast commit commit pathHarshad Shirwadkar1-74/+125
This patch reworks fast commit's commit path to remove locking the journal for the entire duration of a fast commit. Instead, we only lock the journal while marking all the eligible inodes as "committing". This allows handles to make progress in parallel with the fast commit. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://patch.msgid.link/20250508175908.1004880-5-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-09ext4: for committing inode, make ext4_fc_track_inode waitHarshad Shirwadkar1-0/+35
If the inode that's being requested to track using ext4_fc_track_inode is being committed, then wait until the inode finishes the commit. Also, add calls to ext4_fc_track_inode at the right places. With this patch, now calling ext4_reserve_inode_write() results in inode being tracked for next fast commit. This ensures that by the time ext4_reserve_inode_write() returns, it is ready to be modified and won't be committed until the corresponding handle is open. A subtle lock ordering requirement with i_data_sem (which is documented in the code) requires that ext4_fc_track_inode() be called before grabbing i_data_sem. So, this patch also adds explicit ext4_fc_track_inode() calls in places where i_data_sem grabbed. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://patch.msgid.link/20250508175908.1004880-3-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-05-09ext4: convert i_fc_lock to spinlockHarshad Shirwadkar1-10/+9
Convert ext4_inode_info->i_fc_lock to spinlock to avoid sleeping in invalid contexts. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://patch.msgid.link/20250508175908.1004880-2-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2025-01-28ext4 fast_commit: make use of name_snapshot primitivesAl Viro1-24/+5
... rather than open-coding them. As a bonus, that avoids the pointless work with extra allocations, etc. for long names. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-13ext4: cleanup variable name in ext4_fc_del()Dan Carpenter1-2/+2
The variables "&EXT4_SB(inode->i_sb)->s_fc_lock" and "&sbi->s_fc_lock" are the same lock. This function uses a mix of both, which is a bit unsightly and confuses Smatch. Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://patch.msgid.link/96008557-8ff4-44cc-b5e3-ce242212f1a3@stanley.mountain Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-11-13ext4: simplify if conditionJiapeng Chong1-3/+1
The if condition !A || A && B can be simplified to !A || B. ./fs/ext4/fast_commit.c:362:21-23: WARNING !A || A && B is equivalent to !A || B. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9837 Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20240830071713.40565-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-10-05ext4: use handle to mark fc as ineligible in __track_dentry_update()Luis Henriques (SUSE)1-8/+11
Calling ext4_fc_mark_ineligible() with a NULL handle is racy and may result in a fast-commit being done before the filesystem is effectively marked as ineligible. This patch fixes the calls to this function in __track_dentry_update() by adding an extra parameter to the callback used in ext4_fc_track_template(). Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20240923104909.18342-2-luis.henriques@linux.dev Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2024-09-04ext4: make some fast commit functions reuse extents pathBaokun Li1-4/+7
The ext4_find_extent() can update the extent path so that it does not have to allocate and free the path repeatedly, thus reducing the consumption of memory allocation and freeing in the following functions: ext4_ext_clear_bb ext4_ext_replay_set_iblocks ext4_fc_replay_add_range ext4_fc_set_bitmaps_and_counters No functional changes. Note that ext4_find_extent() does not support error pointers, so in this case set path to NULL first. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Link: https://patch.msgid.link/20240822023545.1994557-25-libaokun@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-09-04ext4: get rid of ppath in ext4_ext_insert_extent()Baokun Li1-4/+4
The use of path and ppath is now very confusing, so to make the code more readable, pass path between functions uniformly, and get rid of ppath. To get rid of the ppath in ext4_ext_insert_extent(), the following is done here: * Free the extents path when an error is encountered. * Its caller needs to update ppath if it uses ppath. * Free path when npath is used, free npath when it is not used. * The got_allocated_blocks label in ext4_ext_map_blocks() does not update err now, so err is updated to 0 if the err returned by ext4_ext_search_right() is greater than 0 and is about to enter got_allocated_blocks. No functional changes. Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Link: https://patch.msgid.link/20240822023545.1994557-15-libaokun@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-08-27ext4: fix incorrect tid assumption in ext4_fc_mark_ineligible()Luis Henriques (SUSE)1-4/+11
Function jbd2_journal_shrink_checkpoint_list() assumes that '0' is not a valid value for transaction IDs, which is incorrect. Furthermore, the sbi->s_fc_ineligible_tid handling also makes the same assumption by being initialised to '0'. Fortunately, the sb flag EXT4_MF_FC_INELIGIBLE can be used to check whether sbi->s_fc_ineligible_tid has been previously set instead of comparing it with '0'. Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20240724161119.13448-5-luis.henriques@linux.dev Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2024-08-27ext4: fix fast commit inode enqueueing during a full journal commitLuis Henriques (SUSE)1-1/+14
When a full journal commit is on-going, any fast commit has to be enqueued into a different queue: FC_Q_STAGING instead of FC_Q_MAIN. This enqueueing is done only once, i.e. if an inode is already queued in a previous fast commit entry it won't be enqueued again. However, if a full commit starts _after_ the inode is enqueued into FC_Q_MAIN, the next fast commit needs to be done into FC_Q_STAGING. And this is not being done in function ext4_fc_track_template(). This patch fixes the issue by re-enqueuing an inode into the STAGING queue during the fast commit clean-up callback when doing a full commit. However, to prevent a race with a fast-commit, the clean-up callback has to be called with the journal locked. This bug was found using fstest generic/047. This test creates several 32k bytes files, sync'ing each of them after it's creation, and then shutting down the filesystem. Some data may be loss in this operation; for example a file may have it's size truncated to zero. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20240717172220.14201-1-luis.henriques@linux.dev Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2024-07-09ext4: don't track ranges in fast_commit if inode has inlined dataLuis Henriques (SUSE)1-0/+6
When fast-commit needs to track ranges, it has to handle inodes that have inlined data in a different way because ext4_fc_write_inode_data(), in the actual commit path, will attempt to map the required blocks for the range. However, inodes that have inlined data will have it's data stored in inode->i_block and, eventually, in the extended attribute space. Unfortunately, because fast commit doesn't currently support extended attributes, the solution is to mark this commit as ineligible. Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1039883 Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev> Tested-by: Ben Hutchings <benh@debian.org> Fixes: 9725958bb75c ("ext4: fast commit may miss tracking unwritten range during ftruncate") Link: https://patch.msgid.link/20240618144312.17786-1-luis.henriques@linux.dev Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2024-07-09ext4: fix possible tid_t sequence overflowsLuis Henriques (SUSE)1-4/+4
In the fast commit code there are a few places where tid_t variables are being compared without taking into account the fact that these sequence numbers may wrap. Fix this issue by using the helper functions tid_gt() and tid_geq(). Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://patch.msgid.link/20240529092030.9557-3-luis.henriques@linux.dev Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-10-06ext4: make state in ext4_mb_mark_bb to be boolKemeng Shi1-4/+4
As state could only be either 0 or 1, just make it bool. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230928160407.142069-2-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-02-09ext4: use ext4_fc_tl_mem in fast-commit replay pathEric Biggers1-18/+26
To avoid 'sparse' warnings about missing endianness conversions, don't store native endianness values into struct ext4_fc_tl. Instead, use a separate struct type, ext4_fc_tl_mem. Fixes: dcc5827484d6 ("ext4: factor out ext4_fc_get_tl()") Cc: Ye Bin <yebin10@huawei.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20221217050212.150665-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09jbd2: switch jbd2_submit_inode_data() to use fs-provided hook for data writeoutJan Kara1-1/+1
jbd2_submit_inode_data() hardcoded use of jbd2_journal_submit_inode_data_buffers() for submission of data pages. Make it use j_submit_inode_data_buffers hook instead. This effectively switches ext4 fastcommits to use ext4_writepages() for data writeout instead of generic_writepages(). Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20221207112722.22220-9-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09ext4: simplify fast-commit CRC calculationEric Biggers1-38/+16
Instead of checksumming each field as it is added to the block, just checksum each block before it is written. This is simpler, and also much more efficient. Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221106224841.279231-8-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09ext4: fix off-by-one errors in fast-commit block fillingEric Biggers1-33/+33
Due to several different off-by-one errors, or perhaps due to a late change in design that wasn't fully reflected in the code that was actually merged, there are several very strange constraints on how fast-commit blocks are filled with tlv entries: - tlvs must start at least 10 bytes before the end of the block, even though the minimum tlv length is 8. Otherwise, the replay code will ignore them. (BUG: ext4_fc_reserve_space() could violate this requirement if called with a len of blocksize - 9 or blocksize - 8. Fortunately, this doesn't seem to happen currently.) - tlvs must end at least 1 byte before the end of the block. Otherwise the replay code will consider them to be invalid. This quirk contributed to a bug (fixed by an earlier commit) where uninitialized memory was being leaked to disk in the last byte of blocks. Also, strangely these constraints don't apply to the replay code in e2fsprogs, which will accept any tlvs in the blocks (with no bounds checks at all, but that is a separate issue...). Given that this all seems to be a bug, let's fix it by just filling blocks with tlv entries in the natural way. Note that old kernels will be unable to replay fast-commit journals created by kernels that have this commit. Fixes: aa75f4d3daae ("ext4: main fast-commit commit path") Cc: <stable@vger.kernel.org> # v5.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221106224841.279231-7-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09ext4: fix unaligned memory access in ext4_fc_reserve_space()Eric Biggers1-18/+21
As is done elsewhere in the file, build the struct ext4_fc_tl on the stack and memcpy() it into the buffer, rather than directly writing it to a potentially-unaligned location in the buffer. Fixes: aa75f4d3daae ("ext4: main fast-commit commit path") Cc: <stable@vger.kernel.org> # v5.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221106224841.279231-6-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09ext4: add missing validation of fast-commit record lengthsEric Biggers1-19/+19
Validate the inode and filename lengths in fast-commit journal records so that a malicious fast-commit journal cannot cause a crash by having invalid values for these. Also validate EXT4_FC_TAG_DEL_RANGE. Fixes: aa75f4d3daae ("ext4: main fast-commit commit path") Cc: <stable@vger.kernel.org> # v5.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221106224841.279231-5-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09ext4: fix leaking uninitialized memory in fast-commit journalEric Biggers1-0/+5
When space at the end of fast-commit journal blocks is unused, make sure to zero it out so that uninitialized memory is not leaked to disk. Fixes: aa75f4d3daae ("ext4: main fast-commit commit path") Cc: <stable@vger.kernel.org> # v5.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221106224841.279231-4-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09ext4: don't set up encryption key during jbd2 transactionEric Biggers1-1/+1
Commit a80f7fcf1867 ("ext4: fixup ext4_fc_track_* functions' signature") extended the scope of the transaction in ext4_unlink() too far, making it include the call to ext4_find_entry(). However, ext4_find_entry() can deadlock when called from within a transaction because it may need to set up the directory's encryption key. Fix this by restoring the transaction to its original scope. Reported-by: syzbot+1a748d0007eeac3ab079@syzkaller.appspotmail.com Fixes: a80f7fcf1867 ("ext4: fixup ext4_fc_track_* functions' signature") Cc: <stable@vger.kernel.org> # v5.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221106224841.279231-3-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-12-09ext4: disable fast-commit of encrypted dir operationsEric Biggers1-16/+25
fast-commit of create, link, and unlink operations in encrypted directories is completely broken because the unencrypted filenames are being written to the fast-commit journal instead of the encrypted filenames. These operations can't be replayed, as encryption keys aren't present at journal replay time. It is also an information leak. Until if/when we can get this working properly, make encrypted directory operations ineligible for fast-commit. Note that fast-commit operations on encrypted regular files continue to be allowed, as they seem to work. Fixes: aa75f4d3daae ("ext4: main fast-commit commit path") Cc: <stable@vger.kernel.org> # v5.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221106224841.279231-2-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-11-06ext4: fix fortify warning in fs/ext4/fast_commit.c:1551Theodore Ts'o1-2/+3
With the new fortify string system, rework the memcpy to avoid this warning: memcpy: detected field-spanning write (size 60) of single field "&raw_inode->i_generation" at fs/ext4/fast_commit.c:1551 (size 4) Cc: stable@kernel.org Fixes: 54d9469bc515 ("fortify: Add run-time WARN for cross-field memcpy()") Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-10-01ext4: fix potential out of bound read in ext4_fc_replay_scan()Ye Bin1-2/+36
For scan loop must ensure that at least EXT4_FC_TAG_BASE_LEN space. If remain space less than EXT4_FC_TAG_BASE_LEN which will lead to out of bound read when mounting corrupt file system image. ADD_RANGE/HEAD/TAIL is needed to add extra check when do journal scan, as this three tags will read data during scan, tag length couldn't less than data length which will read. Cc: stable@kernel.org Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20220924075233.2315259-4-yebin10@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-10-01ext4: factor out ext4_fc_get_tl()Ye Bin1-21/+25
Factor out ext4_fc_get_tl() to fill 'tl' with host byte order. Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20220924075233.2315259-3-yebin10@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-10-01ext4: introduce EXT4_FC_TAG_BASE_LEN helperYe Bin1-26/+28
Introduce EXT4_FC_TAG_BASE_LEN helper for calculate length of struct ext4_fc_tl. Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20220924075233.2315259-2-yebin10@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>