kernel/linux.git/fs/inode.c, branch v7.0.11

fs: fix forced iversion increment on lazytime timestamp updates

2026-06-01T15:54:37+00:00

[ Upstream commit 834e98acb748025c04fed3cac9c8954454f4b520 ] When updating timestamps with lazytime enabled, if only I_DIRTY_TIME is set (pure lazytime update), inode_maybe_inc_iversion() should not be forced to increment i_version. The force parameter should only be true when actual data or metadata changes require an iversion bump. The current code uses "!!dirty" which evaluates to true whenever dirty has any bits set, including the I_DIRTY_TIME bit alone. This forces an iversion increment on every lazytime timestamp update, which then sets I_DIRTY_SYNC, triggering expensive log flushes on subsequent fdatasync calls. Andres reported this issue when he noticed a perf regression[1]. Fix this by using "dirty != I_DIRTY_TIME" as the force parameter. This passes false for pure lazytime updates (allowing the I_VERSION_QUERIED optimization to work), while still forcing the increment when dirty contains other flags indicating real changes that require iversion updates. [1] https://lore.kernel.org/linux-xfs/7ys6erh3nnyeerv2nybyfvp7dmaknuxrlxv74wx56ocdothkc6@ekfiadtkfn2r/ Fixes: 85c871a02b03 ("fs: add support for non-blocking timestamp updates") Signed-off-by: Pankaj Raghav Link: https://patch.msgid.link/20260511111918.1793689-1-p.raghav@samsung.com Reviewed-by: Jeff Layton Reviewed-by: Christoph Hellwig Reviewed-by: Carlos Maiolino Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

Merge tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fsverity/linux

2026-02-12T18:41:34+00:00

Pull fsverity updates from Eric Biggers: "fsverity cleanups, speedup, and memory usage optimization from Christoph Hellwig: - Move some logic into common code - Fix btrfs to reject truncates of fsverity files - Improve the readahead implementation - Store each inode's fsverity_info in a hash table instead of using a pointer in the filesystem-specific part of the inode. This optimizes for memory usage in the usual case where most files don't have fsverity enabled. - Look up the fsverity_info fewer times during verification, to amortize the hash table overhead" * tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fsverity/linux: fsverity: remove inode from fsverity_verification_ctx fsverity: use a hashtable to find the fsverity_info btrfs: consolidate fsverity_info lookup f2fs: consolidate fsverity_info lookup ext4: consolidate fsverity_info lookup fs: consolidate fsverity_info lookup in buffer.c fsverity: push out fsverity_info lookup fsverity: deconstify the inode pointer in struct fsverity_info fsverity: kick off hash readahead at data I/O submission time ext4: move ->read_folio and ->readahead to readpage.c readahead: push invalidate_lock out of page_cache_ra_unbounded fsverity: don't issue readahead for non-ENOENT errors from __filemap_get_folio fsverity: start consolidating pagecache code fsverity: pass struct file to ->write_merkle_tree_block f2fs: don't build the fsverity work handler for !CONFIG_FS_VERITY ext4: don't build the fsverity work handler for !CONFIG_FS_VERITY fs,fsverity: clear out fsverity_info from common code fs,fsverity: reject size changes on fsverity files in setattr_prepare

Merge tag 'vfs-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-02-09T23:13:05+00:00

Pull misc vfs updates from Christian Brauner: "This contains a mix of VFS cleanups, performance improvements, API fixes, documentation, and a deprecation notice. Scalability and performance: - Rework pid allocation to only take pidmap_lock once instead of twice during alloc_pid(), improving thread creation/teardown throughput by 10-16% depending on false-sharing luck. Pad the namespace refcount to reduce false-sharing - Track file lock presence via a flag in ->i_opflags instead of reading ->i_flctx, avoiding false-sharing with ->i_readcount on open/close hot paths. Measured 4-16% improvement on 24-core open-in-a-loop benchmarks - Use a consume fence in locks_inode_context() to match the store-release/load-consume idiom, eliminating a hardware fence on some architectures - Annotate cdev_lock with __cacheline_aligned_in_smp to prevent false-sharing - Remove a redundant DCACHE_MANAGED_DENTRY check in __follow_mount_rcu() that never fires since the caller already verifies it, eliminating a 100% mispredicted branch - Fix a 100% mispredicted likely() in devcgroup_inode_permission() that became wrong after a prior code reorder Bug fixes and correctness: - Make insert_inode_locked() wait for inode destruction instead of skipping, fixing a corner case where two matching inodes could exist in the hash - Move f_mode initialization before file_ref_init() in alloc_file() to respect the SLAB_TYPESAFE_BY_RCU ordering contract - Add a WARN_ON_ONCE guard in try_to_free_buffers() for folios with no buffers attached, preventing a null pointer dereference when AS_RELEASE_ALWAYS is set but no release_folio op exists - Fix select restart_block to store end_time as timespec64, avoiding truncation of tv_sec on 32-bit architectures - Make dump_inode() use get_kernel_nofault() to safely access inode and superblock fields, matching the dump_mapping() pattern API modernization: - Make posix_acl_to_xattr() allocate the buffer internally since every single caller was doing it anyway. Reduces boilerplate and unnecessary error checking across ~15 filesystems - Replace deprecated simple_strtoul() with kstrtoul() for the ihash_entries, dhash_entries, mhash_entries, and mphash_entries boot parameters, adding proper error handling - Convert chardev code to use guard(mutex) and __free(kfree) cleanup patterns - Replace min_t() with min() or umin() in VFS code to avoid silently truncating unsigned long to unsigned int - Gate LOOKUP_RCU assertions behind CONFIG_DEBUG_VFS since callers already check the flag Deprecation: - Begin deprecating legacy BSD process accounting (acct(2)). The interface has numerous footguns and better alternatives exist (eBPF) Documentation: - Fix and complete kernel-doc for struct export_operations, removing duplicated documentation between ReST and source - Fix kernel-doc warnings for __start_dirop() and ilookup5_nowait() Testing: - Add a kunit test for initramfs cpio handling of entries with filesize > PATH_MAX Misc: - Add missing include in fs_struct.c" * tag 'vfs-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits) posix_acl: make posix_acl_to_xattr() alloc the buffer fs: make insert_inode_locked() wait for inode destruction initramfs_test: kunit test for cpio.filesize > PATH_MAX fs: improve dump_inode() to safely access inode fields fs: add for 'init_fs' docs: exportfs: Use source code struct documentation fs: move initializing f_mode before file_ref_init() exportfs: Complete kernel-doc for struct export_operations exportfs: Mark struct export_operations functions at kernel-doc exportfs: Fix kernel-doc output for get_name() acct(2): begin the deprecation of legacy BSD process accounting device_cgroup: remove branch hint after code refactor VFS: fix __start_dirop() kernel-doc warnings fs: Describe @isnew parameter in ilookup5_nowait() fs/namei: Remove redundant DCACHE_MANAGED_DENTRY check in __follow_mount_rcu fs: only assert on LOOKUP_RCU when built with CONFIG_DEBUG_VFS select: store end_time as timespec64 in restart block chardev: Switch to guard(mutex) and __free(kfree) namespace: Replace simple_strtoul with kstrtoul to parse boot params dcache: Replace simple_strtoul with kstrtoul in set_dhash_entries ...

Merge tag 'vfs-7.0-rc1.nonblocking_timestamps' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-02-09T19:25:01+00:00

Pull vfs timestamp updates from Christian Brauner: "This contains the changes to support non-blocking timestamp updates. Since commit 66fa3cedf16a ("fs: Add async write file modification handling") file_update_time_flags() unconditionally returns -EAGAIN when any timestamp needs updating and IOCB_NOWAIT is set. This makes non-blocking direct writes impossible on file systems with granular enough timestamps, which in practice means all of them. This reworks the timestamp update path to propagate IOCB_NOWAIT through ->update_time so that file systems which can update timestamps without blocking are no longer penalized. With that groundwork in place, the core change passes IOCB_NOWAIT into ->update_time and returns -EAGAIN only when the file system indicates it would block. XFS implements non-blocking timestamp updates by using the new ->sync_lazytime and open-coding generic_update_time without the S_NOWAIT check, since the lazytime path through the generic helpers can never block in XFS" * tag 'vfs-7.0-rc1.nonblocking_timestamps' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: xfs: enable non-blocking timestamp updates xfs: implement ->sync_lazytime fs: refactor file_update_time_flags fs: add support for non-blocking timestamp updates fs: add a ->sync_lazytime method fs: factor out a sync_lazytime helper fs: refactor ->update_time handling fat: cleanup the flags for fat_truncate_time nfs: split nfs_update_timestamps fs: allow error returns from generic_update_time fs: remove inode_update_time

fs,fsverity: clear out fsverity_info from common code

2026-01-29T17:39:41+00:00

Free the fsverity_info directly in clear_inode instead of requiring file systems to handle it. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: "Darrick J. Wong" Acked-by: David Sterba # btrfs Link: https://lore.kernel.org/r/20260128152630.627409-3-hch@lst.de Signed-off-by: Eric Biggers

fs: make insert_inode_locked() wait for inode destruction

2026-01-14T16:05:35+00:00

This is the only routine which instead skipped instead of waiting. The current behavior is arguably a bug as it results in a corner case where the inode hash can have *two* matching inodes, one of which is on its way out. Ironing out this difference is an incremental step towards sanitizing the API. Signed-off-by: Mateusz Guzik Link: https://patch.msgid.link/20260114094717.236202-1-mjguzik@gmail.com Signed-off-by: Christian Brauner

fs: improve dump_inode() to safely access inode fields

2026-01-14T15:50:38+00:00

Use get_kernel_nofault() to safely access inode and related structures (superblock, file_system_type) to avoid crashing when the inode pointer is invalid. This allows the same pattern as dump_mapping(). Note: The original access method for i_state and i_count is preserved, as get_kernel_nofault() is unnecessary once the inode structure is verified accessible. Reviewed-by: Jan Kara Signed-off-by: Yuto Ohnuki Link: https://patch.msgid.link/20260112181443.81286-1-ytohnuki@amazon.com Reviewed-by: Mateusz Guzik Signed-off-by: Christian Brauner

fs: refactor file_update_time_flags

2026-01-12T13:01:33+00:00

Split all the inode timestamp flags into a helper. This not only makes the code a bit more readable, but also optimizes away the further checks as soon as know we need an update. Signed-off-by: Christoph Hellwig Link: https://patch.msgid.link/20260108141934.2052404-10-hch@lst.de Reviewed-by: Jan Kara Reviewed-by: Jeff Layton Signed-off-by: Christian Brauner

fs: add support for non-blocking timestamp updates

2026-01-12T13:01:33+00:00

Currently file_update_time_flags unconditionally returns -EAGAIN if any timestamp needs to be updated and IOCB_NOWAIT is passed. This makes non-blocking direct writes impossible on file systems with granular enough timestamps. Pass IOCB_NOWAIT to ->update_time and return -EAGAIN if it could block. Signed-off-by: Christoph Hellwig Link: https://patch.msgid.link/20260108141934.2052404-9-hch@lst.de Reviewed-by: Jan Kara Reviewed-by: Jeff Layton Signed-off-by: Christian Brauner

fs: factor out a sync_lazytime helper

2026-01-12T13:01:33+00:00

Centralize how we synchronize a lazytime update into the actual on-disk timestamp into a single helper. Signed-off-by: Christoph Hellwig Link: https://patch.msgid.link/20260108141934.2052404-7-hch@lst.de Reviewed-by: Jan Kara Reviewed-by: Chaitanya Kulkarni Reviewed-by: Jeff Layton Signed-off-by: Christian Brauner