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13 daysMerge tag 'docs-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It was a reasonably busy cycle for docs; changes include: - Add the AGENTS.md symbolic link into the top-level directory in the hopes that LLMs will read it and produce better work - The removal of the Assisted-by requirement, as concluded at the Maintainer Summit - A new "testdocs" make target to run the documentation unit tests - Lots of work on the Portuguese, and Chinese translations; there is now maintenance for the traditional Chinese translations as well ...and the usual pile of minor fixes, documentation updates, etc" * tag 'docs-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (125 commits) docs: add AGENTS.md as a symlink to README docs: kernel-parameters: adjust reserve_mem build option docs: kernel-parameters: don't mix cmdline options & build options docs/ja_JP: translate submitting-patches.rst (review and report tags) docs: remove Assisted-by references Revert "docs: landlock: fix ENOMSG condition in create_ruleset kernel-doc" docs: kdoc: parse context_lock_struct() as struct declaration docs: timers: hpet: Document userspace API and ioctl commands docs: timers: hpet: Modernize file references Documentation: sched-preemption: Add a SPDX license identifier docs: ABI: sysfs-driver-xdata: use literal blocks for console commands docs: ABI: sysfs-class-firmware-attributes: use literal blocks for console commands ABI: sysfs-bus-usb: use literal block for console commands docs/ABI: testing: aspeed-uart-routing: use literal block for console commands docs: kernel-parameters: fix a truncated sentence for preempt=lazy sched/doc: add a preemption model overview docs: ABI: TMR manager: use literal blocks for console I/O Documentation/ABI: IFS: use literal blocks for commands ABI: sysfs-bus-pci: use literal blocks for commands docs: translations: pt_BR: add debugging index ...
2026-09-23fs: port ->setattr() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-24-54ccd48e100b@kernel.org Acked-by: Paul Moore <paul@paul-moore.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->getattr() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-23-54ccd48e100b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->create() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-22-54ccd48e100b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->symlink() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-21-54ccd48e100b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->mkdir() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-20-54ccd48e100b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->rename() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-19-54ccd48e100b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->mknod() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-18-54ccd48e100b@kernel.org Acked-by: Paul Moore <paul@paul-moore.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->tmpfile() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-17-54ccd48e100b@kernel.org Acked-by: Paul Moore <paul@paul-moore.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->get_acl() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-16-54ccd48e100b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->fileattr_set() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-14-54ccd48e100b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port xattr to const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-13-54ccd48e100b@kernel.org Acked-by: Paul Moore <paul@paul-moore.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23fs: port ->permission() to pass const mnt_idmapChristian Brauner
Convert to const struct mnt_idmap. A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive. So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. No functional changes. Link: https://patch.msgid.link/20260901-work-idmap-const-v1-12-54ccd48e100b@kernel.org Acked-by: Paul Moore <paul@paul-moore.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Seth Forshee <sforshee@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-07docs: locking: Fix bracketManuel Ebner
Remove needless '(' from code block. Signed-off-by: Manuel Ebner <manuelebnerli@mailbox.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260902143936.703665-4-manuelebnerli@mailbox.org>
2026-08-27Merge tag 'mm-stable-2026-08-26-15-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff" (Lorenzo Stoakes) Index MAP_PRIVATE file-backed folios by their anonymous page offset to resolve confusion around reverse mapping for zeroed and CoW'd file-backed memory. Use this new VMA anonymous page offset tracking to eliminate index conflicts and lay the foundation for scalable CoW performance improvements. - "promote mapped executable folios after first usage for MGLRU" (Baolin Wang) Make MGLRU's protection of mapped executable file folios more reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance. - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen) Fix per-node proactive reclaim interface's ignoring the swappiness parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness() into a single function that checks proactive_swappiness regardless of kernel configuration. - "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance cost" (Usama Arif) Reduce lru_lock contention in the reclaim path by deriving scan-balance costs from vmstat counters rather than lock-acquired producer updates. Read and decay these cost signals on the reclaim side under a dedicated per-lruvec lock, reducing total LRU lock wait time by over 60% without impacting scan throughput. - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky) Fix two low-risk zram bugs which Sashiko spotted in drive-by review. - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's memcg" (Zi Yan) Fix xas_split_alloc() by enabling target folio memcg charging during splits and adding the missing __GFP_ACCOUNT flag for proper XArray node memory accounting. - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick) Replace hardcoded binary names in selftests/mm/.gitignore with a generic pattern-matching rule to automatically ignore generated test files and avoid manual updates when adding new tests. - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon) Make the incompatibility between FLATMEM and NUMA explicit in mm/Kconfig and remove the unused pgdat_page_ext_init() function. - "zram: fix zstd error paths and add parameter validation" (Haoqin Huang) Clean up zram compression backends by removing redundant error cleanup, adding parameter and dictionary validation, auto-prefixing algorithm error logs, and resetting parameters prior to reinitialization. - "zram: fix stale scan bounds after reinitialization" (Longlong Xia) Prevent out-of-bounds slot accesses during concurrent zram resets by moving table scan bound calculations under dev_lock in writeback_store() and read_block_state(). - "add anon mTHP collapse test cases" (Baolin Wang) Extend selftests helper functions to support arbitrary page orders and add new test cases and options for mTHP collapse in khugepaged. - "selftests/mm: Handle unsupported and transient test conditions" (Muhammad Usama Anjum) Update MM selftests to report a SKIP status instead of a failure when required kernel or filesystem features are unsupported, while adding retry logic for transient page migration errors. - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia) Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled and extend shrink_memcg() to support batch writeback for improved writeback efficiency. - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan) Introduce an IOCTL-based binary interface for memory allocation profiling that enables kernel-side filtering before per-CPU counter aggregation. This eliminates the text-parsing overhead of /proc/allocinfo and provides up to a 20x speedup by transferring only filtered allocation data to userspace. - "better block swap batching and a different take on swap_ops v5" (Christoph Hellwig) Refactor block swap I/O to use swap_iocb for batching instead of single-bio requests and rebase the swap_ops interface, achieving faster swap throughput during kernel builds. - "mm: kmemleak: reduce transient false positives by confirming leaks" (Catalin Marinas) Reduce false-positive kmemleak reports by combining two kmemleak enhancements that add a second confirmation scan and a configurable minimum unreferenced scan count module parameter. - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels" (Breno Leitao) Auto-scanning kernels can generate false-positive memory leak reports on single scans, so this patch defaults min_unref_scans to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming scan. - "swap_ops updates" (Christoph Hellwig) Batching I/O for synchronous swap devices causes performance regressions and filesystem-based swap suffers from double-indirection overhead. This series resolves both issues by reintroducing per-folio writes for synchronous swap and allowing filesystems to directly export their own swap_ops. - "mm/khugepaged: several cleanups" (Nico Pache) khugepaged accumulated redundant state-checking patterns and outdated comments following mTHP integration. Introduce dedicated helpers for PTE validation and event counting while refreshing the internal documentation. - "maple_tree: lock checking and clean ups" (Liam Howlett) Syzbot reports incorrectly blame memory management exit paths for locking bugs, maple tree erase operations risk allocation failures without gfp flags and internal documentation lacks clarity. Improve lock error detection, update docs, fix race and allocation edge cases and optimize erase allocations using a fallback to GFP_KERNEL | GFP_NOFAIL. * tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits) selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC memcg: move LRU size accounting on reparenting instead of copying it mm/vmscan: fix comment logic in balance_pgdat maple_tree: add helper mas_make_walkable() maple_tree: avoid extra gap calculation maple_tree: fix argument name in header maple_tree: change two GFP flags in tests maple_tree: document erase and allocations better maple_tree: avoid mas_erase() and mtree_erase() failures maple_tree: document that erase may use GFP_KERNEL for allocations maple_tree: catch race in mas_alloc_cyclic() maple_tree: add bulk parent set helper maple_tree: micro optimisation of mas_wr_store_type() maple_tree: optimise mas_wr_node_store() when not in rcu mode maple_tree: use prefetched value in mas_wr_store_type() maple_tree: clarify comments on mas_nomem() maple_tree: drop MAPLE_ALLOC_SLOTS maple_tree: drop dead code from mas_extend_spanning_null() maple_tree: documentation fix maple_tree: add write lock checking with lockdep sequence numbers ...
2026-08-24mm/swap: move swap_ops into file systems for file system-based swapChristoph Hellwig
Currently swap to and from file systems goes through two indirect calls between the swap ops and the swap_rw method. Reduce this by directly providing the swap_ops from the file system. For this refactor swap_fs_submit into a swap_fs_prepare_rw helper that initializes the iov_iter on the callers stack so that file systems can call it directly, and use that to initialize file system specific ops in the NFS and SMB clients, which then get passed to swap_fs_activate. Link: https://lore.kernel.org/20260723054622.3460249-4-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Chris Li <chrisl@kernel.org> Cc: Baoquan He <baoquan.he@linux.dev> Cc: Kairui Song <kasong@tencent.com> Cc: Kairui Song <ryncsn@gmail.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Steve French <sfrench@samba.org> Cc: Usama Arif <usama.arif@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24mm/swap: remove SWP_FS_OPSChristoph Hellwig
Provide a swap_fs_activate helper that directly sets up swap_fs_ops, and a flag in struct swap_ops to indicate of NOFS swapping is allowed. Link: https://lore.kernel.org/20260713093350.2154226-7-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <baoquan.he@linux.dev> Cc: Barry Song <baohua@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Kairui Song <kasong@tencent.com> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Youngjun Park <youngjun.park@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-31Remove excl arg to ->create inode_operationNeilBrown
The only time that 'false' is passed as the 'excl' arg to the ->create inode_operation is in lookup_open() when ->atomic_open is not provided by the parent directory. *all* directory inode_operations which do not have ->atomic_open completely ignore the 'excl' arg. Therefore we don't need the 'excl' arg. Those few ->create operations which pay attention to the arg are only ever called with a value of 'true'. We remove that arg and change all ->create operations to behave as those thhe arg were 'true'. Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/178290671516.27465.15984496764174914338@noble.neil.brown.name Reviewed-by: Jori Koolstra <jkoolstra@xs4all.nl> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-16Merge tag 'docs-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "Things have calmed down a bit on the docs front, with no earthshaking changes this time around: - Ongoing work on the Japanese and Portuguese translations - Better integration of the MAINTAINERS file into the rendered documents, including a search interface - A seemingly infinite supply of fixes for typos, minor grammatical issues, and related problems that LLMs find with abandon" * tag 'docs-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (93 commits) docs: pt_BR: Translate 3.Early-stage.rst into Portuguese docs: pt_BR: update "Purpose of Defconfigs" section in maintainer-soc.rst Documentation: bug-hunting.rst: fix grammar docs/ja_JP: translate submitting-patches.rst (interleaved-replies) docs: Fix minor grammatical error docs/{it_it,sp_SP,zh_CN,zh_TW}: update references to removed CONFIG_DEBUG_SLAB Documentation: process: fix brackets Documentation: arch: fix brackets docs/dyndbg: explain flags parse 1st docs/dyndbg: update examples \012 to \n docs: kernel-parameters: Fix stale sticore file paths docs: real-time: Fix duplicated sched(7) text docs: kgdb: Fix stale source file paths docs: sonypi: Fix stale header file path docs: kernel-parameters: Remove sa1100ir IrDA parameter iommu: Documentation: rearrange, update kernel-parameters docs: md: fix grammar in speed_limit description docs: changes.rst: restore pahole 1.26 minimum (regressed by sort) Documentation: Fix syntax of kmalloc_objs example in coding style doc docs: pt_BR: update maintainer-handbooks ...
2026-06-04buffer: Remove b_end_ioMatthew Wilcox (Oracle)
This shrinks buffer_head by 8 bytes, letting us pack more buffer heads per slab. With a Debian config, it shrinks from 104 bytes to 96 bytes which is 42 objects per 4KiB page rather than 39, a 7% reduction in the amount of memory used. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://patch.msgid.link/20260528173150.1093780-33-willy@infradead.org Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-05-15docs: locking: Fix stale dquot.c pathCosta Shulyupin
The quota code was moved from fs/dquot.c to fs/quota/dquot.c in commit 884d179dff3a ("quota: Move quota files into separate directory"). Update the reference. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Costa Shulyupin <costa.shul@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260503160221.1594319-2-costa.shul@redhat.com>
2026-03-29NFSD: Enforce timeout on layout recall and integrate lease manager fencingDai Ngo
When a layout conflict triggers a recall, enforcing a timeout is necessary to prevent excessive nfsd threads from being blocked in __break_lease ensuring the server continues servicing incoming requests efficiently. This patch introduces a new function to lease_manager_operations: lm_breaker_timedout: Invoked when a lease recall times out and is about to be disposed of. This function enables the lease manager to inform the caller whether the file_lease should remain on the flc_list or be disposed of. For the NFSD lease manager, this function now handles layout recall timeouts. If the layout type supports fencing and the client has not been fenced, a fence operation is triggered to prevent the client from accessing the block device. While the fencing operation is in progress, the conflicting file_lease remains on the flc_list until fencing is complete. This guarantees that no other clients can access the file, and the client with exclusive access is properly blocked before disposal. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-02-09Merge tag 'vfs-7.0-rc1.namespace' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs mount updates from Christian Brauner: - statmount: accept fd as a parameter Extend struct mnt_id_req with a file descriptor field and a new STATMOUNT_BY_FD flag. When set, statmount() returns mount information for the mount the fd resides on — including detached mounts (unmounted via umount2(MNT_DETACH)). For detached mounts the STATMOUNT_MNT_POINT and STATMOUNT_MNT_NS_ID mask bits are cleared since neither is meaningful. The capability check is skipped for STATMOUNT_BY_FD since holding an fd already implies prior access to the mount and equivalent information is available through fstatfs() and /proc/pid/mountinfo without privilege. Includes comprehensive selftests covering both attached and detached mount cases. - fs: Remove internal old mount API code (1 patch) Now that every in-tree filesystem has been converted to the new mount API, remove all the legacy shim code in fs_context.c that handled unconverted filesystems. This deletes ~280 lines including legacy_init_fs_context(), the legacy_fs_context struct, and associated wrappers. The mount(2) syscall path for userspace remains untouched. Documentation references to the legacy callbacks are cleaned up. - mount: add OPEN_TREE_NAMESPACE to open_tree() Container runtimes currently use CLONE_NEWNS to copy the caller's entire mount namespace — only to then pivot_root() and recursively unmount everything they just copied. With large mount tables and thousands of parallel container launches this creates significant contention on the namespace semaphore. OPEN_TREE_NAMESPACE copies only the specified mount tree (like OPEN_TREE_CLONE) but returns a mount namespace fd instead of a detached mount fd. The new namespace contains the copied tree mounted on top of a clone of the real rootfs. This functions as a combined unshare(CLONE_NEWNS) + pivot_root() in a single syscall. Works with user namespaces: an unshare(CLONE_NEWUSER) followed by OPEN_TREE_NAMESPACE creates a mount namespace owned by the new user namespace. Mount namespace file mounts are excluded from the copy to prevent cycles. Includes ~1000 lines of selftests" * tag 'vfs-7.0-rc1.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: selftests/open_tree: add OPEN_TREE_NAMESPACE tests mount: add OPEN_TREE_NAMESPACE fs: Remove internal old mount API code selftests: statmount: tests for STATMOUNT_BY_FD statmount: accept fd as a parameter statmount: permission check should return EPERM
2026-02-09Merge tag 'vfs-7.0-rc1.nonblocking_timestamps' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs 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
2026-01-12fs: add a ->sync_lazytime methodChristoph Hellwig
Allow the file system to explicitly implement lazytime syncing instead of pigging back on generic inode dirtying. This allows to simplify the XFS implementation and prepares for non-blocking lazytime timestamp updates. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260108141934.2052404-8-hch@lst.de Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-12fs: refactor ->update_time handlingChristoph Hellwig
Pass the type of update (atime vs c/mtime plus version) as an enum instead of a set of flags that caused all kinds of confusion. Because inode_update_timestamps now can't return a modified version of those flags, return the I_DIRTY_* flags needed to persist the update, which is what the main caller in generic_update_time wants anyway, and which is suitable for the other callers that only want to know if an update happened. The whole update_time path keeps the flags argument, which will be used to support non-blocking updates soon even if it is unused, and (the slightly renamed) inode_update_time also gains the possibility to return a negative errno to support this. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260108141934.2052404-6-hch@lst.de Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-12-15filelock: allow lease_managers to dictate what qualifies as a conflictJeff Layton
Requesting a delegation on a file from the userland fcntl() interface currently succeeds when there are conflicting opens present. This is because the lease handling code ignores conflicting opens for FL_LAYOUT and FL_DELEG leases. This was a hack put in place long ago, because nfsd already checks for conflicts in its own way. The kernel needs to perform this check for userland delegations the same way it is done for leases, however. Make this dependent on the lease_manager by adding a new ->lm_open_conflict() lease_manager operation and have generic_add_lease() call that instead of check_conflicting_open(). Morph check_conflicting_open() into a ->lm_open_conflict() op that is only called for userland leases/delegations. Set the ->lm_open_conflict() operations for nfsd to trivial functions that always return 0. Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20251204-dir-deleg-ro-v2-2-22d37f92ce2c@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-12-15fs: Remove internal old mount API codeEric Sandeen
Now that the last in-tree filesystem has been converted to the new mount API, remove all legacy mount API code designed to handle un-converted filesystems, and remove associated documentation as well. (The code to handle the legacy mount(2) syscall from userspace is still in place, of course.) Tested with an allmodconfig build on x86_64, and a sanity check of an old mount(2) syscall mount. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Link: https://patch.msgid.link/20251212174403.2882183-1-sandeen@redhat.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-13block: switch ->getgeo() to struct gendiskAl Viro
Instances are happier that way and it makes more sense anyway - the only part of the result that is related to partition we are given is the start sector, and that has been filled in by the caller. Everything else is a function of the disk. Only one instance (DASD) is ever looking at anything other than bdev->bd_disk and that one is trivial to adjust. Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-07-28Merge tag 'vfs-6.17-rc1.fileattr' of ↵Linus Torvalds
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
2025-07-16fs: change write_begin/write_end interface to take struct kiocb *Taotao Chen
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>
2025-07-04tree-wide: s/struct fileattr/struct file_kattr/gChristian Brauner
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>
2025-04-07fs: Remove aops->writepageMatthew Wilcox (Oracle)
All callers and implementations are now removed, so remove the operation and update the documentation to match. Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org> Link: https://lore.kernel.org/r/20250402150005.2309458-10-willy@infradead.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-27Change inode_operations.mkdir to return struct dentry *NeilBrown
Some filesystems, such as NFS, cifs, ceph, and fuse, do not have complete control of sequencing on the actual filesystem (e.g. on a different server) and may find that the inode created for a mkdir request already exists in the icache and dcache by the time the mkdir request returns. For example, if the filesystem is mounted twice the directory could be visible on the other mount before it is on the original mount, and a pair of name_to_handle_at(), open_by_handle_at() calls could instantiate the directory inode with an IS_ROOT() dentry before the first mkdir returns. This means that the dentry passed to ->mkdir() may not be the one that is associated with the inode after the ->mkdir() completes. Some callers need to interact with the inode after the ->mkdir completes and they currently need to perform a lookup in the (rare) case that the dentry is no longer hashed. This lookup-after-mkdir requires that the directory remains locked to avoid races. Planned future patches to lock the dentry rather than the directory will mean that this lookup cannot be performed atomically with the mkdir. To remove this barrier, this patch changes ->mkdir to return the resulting dentry if it is different from the one passed in. Possible returns are: NULL - the directory was created and no other dentry was used ERR_PTR() - an error occurred non-NULL - this other dentry was spliced in This patch only changes file-systems to return "ERR_PTR(err)" instead of "err" or equivalent transformations. Subsequent patches will make further changes to some file-systems to return a correct dentry. Not all filesystems reliably result in a positive hashed dentry: - NFS, cifs, hostfs will sometimes need to perform a lookup of the name to get inode information. Races could result in this returning something different. Note that this lookup is non-atomic which is what we are trying to avoid. Placing the lookup in filesystem code means it only happens when the filesystem has no other option. - kernfs and tracefs leave the dentry negative and the ->revalidate operation ensures that lookup will be called to correctly populate the dentry. This could be fixed but I don't think it is important to any of the users of vfs_mkdir() which look at the dentry. The recommendation to use d_drop();d_splice_alias() is ugly but fits with current practice. A planned future patch will change this. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250227013949.536172-2-neilb@suse.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-01-279p: fix ->rename_sem exclusionAl Viro
9p wants to be able to build a path from given dentry to fs root and keep it valid over a blocking operation. ->s_vfs_rename_mutex would be a natural candidate, but there are places where we need that and where we have no way to tell if ->s_vfs_rename_mutex is already held deeper in callchain. Moreover, it's only held for cross-directory renames; name changes within the same directory happen without it. Solution: * have d_move() done in ->rename() rather than in its caller * maintain a 9p-private rwsem (per-filesystem) * hold it exclusive over the relevant part of ->rename() * hold it shared over the places where we want the path. That almost works. FS_RENAME_DOES_D_MOVE is enough to put all d_move() and d_exchange() calls under filesystem's control. However, there's also __d_unalias(), which isn't covered by any of that. If ->lookup() hits a directory inode with preexisting dentry elsewhere (due to e.g. rename done on server behind our back), d_splice_alias() called by ->lookup() will move/rename that alias. Add a couple of optional methods, so that __d_unalias() would do if alias->d_op->d_unalias_trylock != NULL if (!alias->d_op->d_unalias_trylock(alias)) fail (resulting in -ESTALE from lookup) __d_move(...) if alias->d_op->d_unalias_unlock != NULL alias->d_unalias_unlock(alias) where it currently does __d_move(). 9p instances do down_write_trylock() and up_write() of ->rename_mutex. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27Pass parent directory inode and expected name to ->d_revalidate()Al Viro
->d_revalidate() often needs to access dentry parent and name; that has to be done carefully, since the locking environment varies from caller to caller. We are not guaranteed that dentry in question will not be moved right under us - not unless the filesystem is such that nothing on it ever gets renamed. It can be dealt with, but that results in boilerplate code that isn't even needed - the callers normally have just found the dentry via dcache lookup and want to verify that it's in the right place; they already have the values of ->d_parent and ->d_name stable. There is a couple of exceptions (overlayfs and, to less extent, ecryptfs), but for the majority of calls that song and dance is not needed at all. It's easier to make ecryptfs and overlayfs find and pass those values if there's a ->d_revalidate() instance to be called, rather than doing that in the instances. This commit only changes the calling conventions; making use of supplied values is left to followups. NOTE: some instances need more than just the parent - things like CIFS may need to build an entire path from filesystem root, so they need more precautions than the usual boilerplate. This series doesn't do anything to that need - these filesystems have to keep their locking mechanisms (rename_lock loops, use of dentry_path_raw(), private rwsem a-la v9fs). One thing to keep in mind when using name is that name->name will normally point into the pathname being resolved; the filename in question occupies name->len bytes starting at name->name, and there is NUL somewhere after it, but it the next byte might very well be '/' rather than '\0'. Do not ignore name->len. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-08-07fs: Convert aops->write_begin to take a folioMatthew Wilcox (Oracle)
Convert all callers from working on a page to working on one page of a folio (support for working on an entire folio can come later). Removes a lot of folio->page->folio conversions. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-08-07fs: Convert aops->write_end to take a folioMatthew Wilcox (Oracle)
Most callers have a folio, and most implementations operate on a folio, so remove the conversion from folio->page->folio to fit through this interface. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-06fs: remove the inode argument to ->d_real() methodAmir Goldstein
The only remaining user of ->d_real() method is d_real_inode(), which passed NULL inode argument to get the real data dentry. There are no longer any users that call ->d_real() with a non-NULL inode argument for getting a detry from a specific underlying layer. Remove the inode argument of the method and replace it with an integer 'type' argument, to allow callers to request the real metadata dentry instead of the real data dentry. All the current users of d_real_inode() (e.g. uprobe) continue to get the real data inode. Caller that need to get the real metadata inode (e.g. IMA/EVM) can use d_inode(d_real(dentry, D_REAL_METADATA)). Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20240202110132.1584111-3-amir73il@gmail.com Tested-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-01-11Merge tag 'pull-rename' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull rename updates from Al Viro: "Fix directory locking scheme on rename This was broken in 6.5; we really can't lock two unrelated directories without holding ->s_vfs_rename_mutex first and in case of same-parent rename of a subdirectory 6.5 ends up doing just that" * tag 'pull-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: rename(): avoid a deadlock in the case of parents having no common ancestor kill lock_two_inodes() rename(): fix the locking of subdirectories f2fs: Avoid reading renamed directory if parent does not change ext4: don't access the source subdirectory content on same-directory rename ext2: Avoid reading renamed directory if parent does not change udf_rename(): only access the child content on cross-directory rename ocfs2: Avoid touching renamed directory if parent does not change reiserfs: Avoid touching renamed directory if parent does not change
2023-12-10fs: convert error_remove_page to error_remove_folioMatthew Wilcox (Oracle)
There were already assertions that we were not passing a tail page to error_remove_page(), so make the compiler enforce that by converting everything to pass and use a folio. Link: https://lkml.kernel.org/r/20231117161447.2461643-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-25rename(): fix the locking of subdirectoriesAl Viro
We should never lock two subdirectories without having taken ->s_vfs_rename_mutex; inode pointer order or not, the "order" proposed in 28eceeda130f "fs: Lock moved directories" is not transitive, with the usual consequences. The rationale for locking renamed subdirectory in all cases was the possibility of race between rename modifying .. in a subdirectory to reflect the new parent and another thread modifying the same subdirectory. For a lot of filesystems that's not a problem, but for some it can lead to trouble (e.g. the case when short directory contents is kept in the inode, but creating a file in it might push it across the size limit and copy its contents into separate data block(s)). However, we need that only in case when the parent does change - otherwise ->rename() doesn't need to do anything with .. entry in the first place. Some instances are lazy and do a tautological update anyway, but it's really not hard to avoid. Amended locking rules for rename(): find the parent(s) of source and target if source and target have the same parent lock the common parent else lock ->s_vfs_rename_mutex lock both parents, in ancestor-first order; if neither is an ancestor of another, lock the parent of source first. find the source and target. if source and target have the same parent if operation is an overwriting rename of a subdirectory lock the target subdirectory else if source is a subdirectory lock the source if target is a subdirectory lock the target lock non-directories involved, in inode pointer order if both source and target are such. That way we are guaranteed that parents are locked (for obvious reasons), that any renamed non-directory is locked (nfsd relies upon that), that any victim is locked (emptiness check needs that, among other things) and subdirectory that changes parent is locked (needed to protect the update of .. entries). We are also guaranteed that any operation locking more than one directory either takes ->s_vfs_rename_mutex or locks a parent followed by its child. Cc: stable@vger.kernel.org Fixes: 28eceeda130f "fs: Lock moved directories" Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-08-30Merge tag 'docs-6.6' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "Documentation work keeps chugging along; this includes: - Work from Carlos Bilbao to integrate rustdoc output into the generated HTML documentation. This took some work to figure out how to do it without slowing the docs build and without creating people who don't have Rust installed, but Carlos got there - Move the loongarch and mips architecture documentation under Documentation/arch/ - Some more maintainer documentation from Jakub ... plus the usual assortment of updates, translations, and fixes" * tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits) Docu: genericirq.rst: fix irq-example input: docs: pxrc: remove reference to phoenix-sim Documentation: serial-console: Fix literal block marker docs/mm: remove references to hmm_mirror ops and clean typos docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add() Documentation: Fix typos Documentation/ABI: Fix typos scripts: kernel-doc: fix macro handling in enums scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN] Documentation: riscv: Update boot image header since EFI stub is supported Documentation: riscv: Add early boot document Documentation: arm: Add bootargs to the table of added DT parameters docs: kernel-parameters: Refer to the correct bitmap function doc: update params of memhp_default_state= docs: Add book to process/kernel-docs.rst docs: sparse: fix invalid link addresses docs: vfs: clean up after the iterate() removal docs: Add a section on surveys to the researcher guidelines docs: move mips under arch docs: move loongarch under arch ...
2023-08-29Merge tag 'mm-stable-2023-08-28-18-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Some swap cleanups from Ma Wupeng ("fix WARN_ON in add_to_avail_list") - Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which reduces the special-case code for handling hugetlb pages in GUP. It also speeds up GUP handling of transparent hugepages. - Peng Zhang provides some maple tree speedups ("Optimize the fast path of mas_store()"). - Sergey Senozhatsky has improved te performance of zsmalloc during compaction (zsmalloc: small compaction improvements"). - Domenico Cerasuolo has developed additional selftest code for zswap ("selftests: cgroup: add zswap test program"). - xu xin has doe some work on KSM's handling of zero pages. These changes are mainly to enable the user to better understand the effectiveness of KSM's treatment of zero pages ("ksm: support tracking KSM-placed zero-pages"). - Jeff Xu has fixes the behaviour of memfd's MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED"). - David Howells has fixed an fscache optimization ("mm, netfs, fscache: Stop read optimisation when folio removed from pagecache"). - Axel Rasmussen has given userfaultfd the ability to simulate memory poisoning ("add UFFDIO_POISON to simulate memory poisoning with UFFD"). - Miaohe Lin has contributed some routine maintenance work on the memory-failure code ("mm: memory-failure: remove unneeded PageHuge() check"). - Peng Zhang has contributed some maintenance work on the maple tree code ("Improve the validation for maple tree and some cleanup"). - Hugh Dickins has optimized the collapsing of shmem or file pages into THPs ("mm: free retracted page table by RCU"). - Jiaqi Yan has a patch series which permits us to use the healthy subpages within a hardware poisoned huge page for general purposes ("Improve hugetlbfs read on HWPOISON hugepages"). - Kemeng Shi has done some maintenance work on the pagetable-check code ("Remove unused parameters in page_table_check"). - More folioification work from Matthew Wilcox ("More filesystem folio conversions for 6.6"), ("Followup folio conversions for zswap"). And from ZhangPeng ("Convert several functions in page_io.c to use a folio"). - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext"). - Baoquan He has converted some architectures to use the GENERIC_IOREMAP ioremap()/iounmap() code ("mm: ioremap: Convert architectures to take GENERIC_IOREMAP way"). - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support batched/deferred tlb shootdown during page reclamation/migration"). - Better maple tree lockdep checking from Liam Howlett ("More strict maple tree lockdep"). Liam also developed some efficiency improvements ("Reduce preallocations for maple tree"). - Cleanup and optimization to the secondary IOMMU TLB invalidation, from Alistair Popple ("Invalidate secondary IOMMU TLB on permission upgrade"). - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes for arm64"). - Kemeng Shi provides some maintenance work on the compaction code ("Two minor cleanups for compaction"). - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle most file-backed faults under the VMA lock"). - Aneesh Kumar contributes code to use the vmemmap optimization for DAX on ppc64, under some circumstances ("Add support for DAX vmemmap optimization for ppc64"). - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client data in page_ext"), ("minor cleanups to page_ext header"). - Some zswap cleanups from Johannes Weiner ("mm: zswap: three cleanups"). - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan"). - VMA handling cleanups from Kefeng Wang ("mm: convert to vma_is_initial_heap/stack()"). - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes: implement DAMOS tried total bytes file"), ("Extend DAMOS filters for address ranges and DAMON monitoring targets"). - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction"). - Liam Howlett has improved the maple tree node replacement code ("maple_tree: Change replacement strategy"). - ZhangPeng has a general code cleanup - use the K() macro more widely ("cleanup with helper macro K()"). - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for memmap on memory feature on ppc64"). - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list in page_alloc"), ("Two minor cleanups for get pageblock migratetype"). - Vishal Moola introduces a memory descriptor for page table tracking, "struct ptdesc" ("Split ptdesc from struct page"). - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups for vm.memfd_noexec"). - MM include file rationalization from Hugh Dickins ("arch: include asm/cacheflush.h in asm/hugetlb.h"). - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text output"). - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use object_cache instead of kmemleak_initialized"). - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor and _folio_order"). - A VMA locking scalability improvement from Suren Baghdasaryan ("Per-VMA lock support for swap and userfaults"). - pagetable handling cleanups from Matthew Wilcox ("New page table range API"). - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop using page->private on tail pages for THP_SWAP + cleanups"). - Cleanups and speedups to the hugetlb fault handling from Matthew Wilcox ("Change calling convention for ->huge_fault"). - Matthew Wilcox has also done some maintenance work on the MM subsystem documentation ("Improve mm documentation"). * tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (489 commits) maple_tree: shrink struct maple_tree maple_tree: clean up mas_wr_append() secretmem: convert page_is_secretmem() to folio_is_secretmem() nios2: fix flush_dcache_page() for usage from irq context hugetlb: add documentation for vma_kernel_pagesize() mm: add orphaned kernel-doc to the rst files. mm: fix clean_record_shared_mapping_range kernel-doc mm: fix get_mctgt_type() kernel-doc mm: fix kernel-doc warning from tlb_flush_rmaps() mm: remove enum page_entry_size mm: allow ->huge_fault() to be called without the mmap_lock held mm: move PMD_ORDER to pgtable.h mm: remove checks for pte_index memcg: remove duplication detection for mem_cgroup_uncharge_swap mm/huge_memory: work on folio->swap instead of page->private when splitting folio mm/swap: inline folio_set_swap_entry() and folio_swap_entry() mm/swap: use dedicated entry for swap in folio mm/swap: stop using page->private on tail pages for THP_SWAP selftests/mm: fix WARNING comparing pointer to 0 selftests: cgroup: fix test_kmem_memcg_deletion kernel mem check ...
2023-08-28Merge tag 'iomap-6.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull iomap updates from Darrick Wong: "We've got some big changes for this release -- I'm very happy to be landing willy's work to enable large folios for the page cache for general read and write IOs when the fs can make contiguous space allocations, and Ritesh's work to track sub-folio dirty state to eliminate the write amplification problems inherent in using large folios. As a bonus, io_uring can now process write completions in the caller's context instead of bouncing through a workqueue, which should reduce io latency dramatically. IOWs, XFS should see a nice performance bump for both IO paths. Summary: - Make large writes to the page cache fill sparse parts of the cache with large folios, then use large memcpy calls for the large folio. - Track the per-block dirty state of each large folio so that a buffered write to a single byte on a large folio does not result in a (potentially) multi-megabyte writeback IO. - Allow some directio completions to be performed in the initiating task's context instead of punting through a workqueue. This will reduce latency for some io_uring requests" * tag 'iomap-6.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (26 commits) iomap: support IOCB_DIO_CALLER_COMP io_uring/rw: add write support for IOCB_DIO_CALLER_COMP fs: add IOCB flags related to passing back dio completions iomap: add IOMAP_DIO_INLINE_COMP iomap: only set iocb->private for polled bio iomap: treat a write through cache the same as FUA iomap: use an unsigned type for IOMAP_DIO_* defines iomap: cleanup up iomap_dio_bio_end_io() iomap: Add per-block dirty state tracking to improve performance iomap: Allocate ifs in ->write_begin() early iomap: Refactor iomap_write_delalloc_punch() function out iomap: Use iomap_punch_t typedef iomap: Fix possible overflow condition in iomap_write_delalloc_scan iomap: Add some uptodate state handling helpers for ifs state bitmap iomap: Drop ifs argument from iomap_set_range_uptodate() iomap: Rename iomap_page to iomap_folio_state and others iomap: Copy larger chunks from userspace iomap: Create large folios in the buffered write path filemap: Allow __filemap_get_folio to allocate large folios filemap: Add fgf_t typedef ...
2023-08-28Merge tag 'v6.6-vfs.tmpfs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull libfs and tmpfs updates from Christian Brauner: "This cycle saw a lot of work for tmpfs that required changes to the vfs layer. Andrew, Hugh, and I decided to take tmpfs through vfs this cycle. Things will go back to mm next cycle. Features ======== - By far the biggest work is the quota support for tmpfs. New tmpfs quota infrastructure is added to support it and a new QFMT_SHMEM uapi option is exposed. This offers user and group quotas to tmpfs (project quotas will be added later). Similar to other filesystems tmpfs quota are not supported within user namespaces yet. - Add support for user xattrs. While tmpfs already supports security xattrs (security.*) and POSIX ACLs for a long time it lacked support for user xattrs (user.*). With this pull request tmpfs will be able to support a limited number of user xattrs. This is accompanied by a fix (see below) to limit persistent simple xattr allocations. - Add support for stable directory offsets. Currently tmpfs relies on the libfs provided cursor-based mechanism for readdir. This causes issues when a tmpfs filesystem is exported via NFS. NFS clients do not open directories. Instead, each server-side readdir operation opens the directory, reads it, and then closes it. Since the cursor state for that directory is associated with the opened file it is discarded after each readdir operation. Such directory offsets are not just cached by NFS clients but also various userspace libraries based on these clients. As it stands there is no way to invalidate the caches when directory offsets have changed and the whole application depends on unchanging directory offsets. At LSFMM we discussed how to solve this problem and decided to support stable directory offsets. libfs now allows filesystems like tmpfs to use an xarrary to map a directory offset to a dentry. This mechanism is currently only used by tmpfs but can be supported by others as well. Fixes ===== - Change persistent simple xattrs allocations in libfs from GFP_KERNEL to GPF_KERNEL_ACCOUNT so they're subject to memory cgroup limits. Since this is a change to libfs it affects both tmpfs and kernfs. - Correctly verify {g,u}id mount options. A new filesystem context is created via fsopen() which records the namespace that becomes the owning namespace of the superblock when fsconfig(FSCONFIG_CMD_CREATE) is called for filesystems that are mountable in namespaces. However, fsconfig() calls can occur in a namespace different from the namespace where fsopen() has been called. Currently, when fsconfig() is called to set {g,u}id mount options the requested {g,u}id is mapped into a k{g,u}id according to the namespace where fsconfig() was called from. The resulting k{g,u}id is not guaranteed to be resolvable in the namespace of the filesystem (the one that fsopen() was called in). This means it's possible for an unprivileged user to create files owned by any group in a tmpfs mount since it's possible to set the setid bits on the tmpfs directory. The contract for {g,u}id mount options and {g,u}id values in general set from userspace has always been that they are translated according to the caller's idmapping. In so far, tmpfs has been doing the correct thing. But since tmpfs is mountable in unprivileged contexts it is also necessary to verify that the resulting {k,g}uid is representable in the namespace of the superblock to avoid such bugs. The new mount api's cross-namespace delegation abilities are already widely used. Having talked to a bunch of userspace this is the most faithful solution with minimal regression risks" * tag 'v6.6-vfs.tmpfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: tmpfs,xattr: GFP_KERNEL_ACCOUNT for simple xattrs mm: invalidation check mapping before folio_contains tmpfs: trivial support for direct IO tmpfs,xattr: enable limited user extended attributes tmpfs: track free_ispace instead of free_inodes xattr: simple_xattr_set() return old_xattr to be freed tmpfs: verify {g,u}id mount options correctly shmem: move spinlock into shmem_recalc_inode() to fix quota support libfs: Remove parent dentry locking in offset_iterate_dir() libfs: Add a lock class for the offset map's xa_lock shmem: stable directory offsets shmem: Refactor shmem_symlink() libfs: Add directory operations for stable offsets shmem: fix quota lock nesting in huge hole handling shmem: Add default quota limit mount options shmem: quota support shmem: prepare shmem quota infrastructure quota: Check presence of quota operation structures instead of ->quota_read and ->quota_write callbacks shmem: make shmem_get_inode() return ERR_PTR instead of NULL shmem: make shmem_inode_acct_block() return error
2023-08-24mm: allow ->huge_fault() to be called without the mmap_lock heldMatthew Wilcox (Oracle)
Remove the checks for the VMA lock being held, allowing the page fault path to call into the filesystem instead of retrying with the mmap_lock held. This will improve scalability for DAX page faults. Also update the documentation to match (and fix some other changes that have happened recently). Link: https://lkml.kernel.org/r/20230818202335.2739663-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-24mm: convert do_set_pte() to set_pte_range()Yin Fengwei
set_pte_range() allows to setup page table entries for a specific range. It takes advantage of batched rmap update for large folio. It now takes care of calling update_mmu_cache_range(). Link: https://lkml.kernel.org/r/20230802151406.3735276-37-willy@infradead.org Signed-off-by: Yin Fengwei <fengwei.yin@intel.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18docs: vfs: clean up after the iterate() removalJonathan Corbet
Commit 3e3271549670 ("vfs: get rid of old '->iterate' directory operation") removed the iterate() file_operations member, but neglected to clean up the associated documentation. Get rid of the leftovers. Link: https://lore.kernel.org/r/874jl945bv.fsf@meer.lwn.net Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-08-09libfs: Add directory operations for stable offsetsChuck Lever
Create a vector of directory operations in fs/libfs.c that handles directory seeks and readdir via stable offsets instead of the current cursor-based mechanism. For the moment these are unused. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Message-Id: <168814732984.530310.11190772066786107220.stgit@manet.1015granger.net> Signed-off-by: Christian Brauner <brauner@kernel.org>