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2026-08-20Merge tag 'for-7.3/block-20260819' of ↵Linus Torvalds1-4/+1
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull block updates from Jens Axboe: - NVMe updates via Keith: - Enable Clang context analysis for the nvme host driver, adding context annotations across core, fabrics, rdma, tcp and pci - nvmet reservation state exposed through a new namespace-level debugfs directory, plus ABI documentation for the host sysfs and target configfs interfaces - nvme-tcp host memory disclosure fixes on the read path: reject a read that transferred too few bytes, don't accept C2HData based on blk_rq_payload_bytes() alone, and fix the R2T case for a read command - Parallelize nvme-rdma I/O queue allocation and startup (Surabhi) - Apple nvme fixes and quirks: page aligned admin queue buffers, destroy the admin queue on removal, and various DMA/NVMMU correctness fixes - A large pile of nvmet and host fixes for out-of-bounds reads, refcount/resource leaks, and NULL derefs across auth, zns, passthru, pci-epf, rdma and configfs - Various other fixes and cleanups - MD updates via Yu Kuai: - llbitmap reshape support, the large series wiring exact bitmap mapping and reshape lifecycle through raid5 and raid10, growing the page cache in place, and remapping checkpointed bits as reshape progresses - raid5 fixes for lockless max_nr_stripes and recovery_offset accesses, a reshape deadlock with more failed devices than max degraded, and bitmap batch counter consistency - Atomic write handling for raid1/raid10, and removal of the REQ_NOWAIT support from raid1/10/456 - raid5-ppl use-after-free fix in ppl_do_flush() - A batch of smaller fixes across md core and the bitmap code - s390/dasd ESE full-track write support and the surrounding infrastructure, plus enabling CONTEXT_ANALYSIS for s390/block - RWF_DONTCACHE support for block devices, built on new task-context bio completion infrastructure, and wiring it up for the iomap and buffer dropbehind writeback paths - Async io_uring zone reset all, plus zone management command cleanups allowing REQ_NOWAIT and tightening conventional zone rejection - Block integrity refactoring: lift BIP_CHECK_FLAGS to the shared header, handle nogenerate/noverify properly in fs-integrity, and drop the blk-integrity.h include from bdev.c - Split out a new blk_plug.h header - ublk improvements: add UBLK_F_IO_DESC_SIZE, split request validation from io_desc init, reject non-power-of-2 zone sizes in SET_PARAMS, and a series of hardening fixes around map/unmap and auto buf reg - null_blk cleanups and configfs serialization fixes - nbd queue freeze removal on the setup paths, and a new pre_defined_connections module parameter for pre-created devices - blk-cgroup fixes for the race between policy activation and blkg destruction, and accounting per-cpu stats over possible CPUs across blk-stat, iolatency, iocost and kyber - Various dio fixes: leak on metadata mapping error, validate user space vectors during extraction, and set dma_alignment from the backing file for loop and zloop direct I/O - bio cleanups - Various other fixes and cleanups all over * tag 'for-7.3/block-20260819' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (241 commits) nbd: add pre_defined_connections module parameter for pre-created devices nbd: remove queue freeze for newly created nbd from netlink path nbd: factor out a nbd_genl_foreach_sock nbd: skip queue freeze when setting size at device startup nbd: remove queue freeze in nbd_add_socket nbd: clear queue limits on disconnect nbd: disallow NBD_SET_SOCK on an active device nbd: simplify find_fallback() by removing redundant logic blk-mq: add missing call to srcu_barrier() in blk_mq_free_tag_set() block: mtip32xx: synchronize ioctls with device removal ublk: avoid teardown retry loop on xarray allocation failure null_blk: fix UBSAN shift-out-of-bounds when zone_size is 0 or overflows block: don't include blk-integrity.h in bdev.c xfs: avoid double deferrals for RWF_DONTCACHE writes loop: Fix recently introduced lock inversion block: set QUEUE_FLAG_DYING unconditionally in blk_mark_disk_dead() swim3: Add missing MODULE_DESCRIPTION selftests: ublk: add SET_PARAMS validation test selftests: ublk: add helper for SET_PARAMS ublk: reject non-power-of-2 zone sizes in SET_PARAMS ...
2026-08-17Merge tag 'vfs-7.3-rc1.iomap' of ↵Linus Torvalds1-17/+161
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull iomap updates from Christian Brauner: "The bulk of this is the conversion of iomap to a single ->iomap_next() callback and thus finishing the move to an iterator model. Every iomap operation drove its iteration through a struct iomap_ops holding ->iomap_begin() and ->iomap_end(). iomap_iter() only ever sees those as pointers. That means every step of every iteration is an indirect call. This collapses both into one ->iomap_next() callback that finishes the previous mapping and produces the next one. This lets callers inline the iteration loop and pass its ->iomap_next() as a compile time constant. That means the compiler can turn it into a direct and hence inlineable call. This also allows future callers to express custom logic to drive the iteration forward better. xfs, btrfs, ext4, ext2, erofs, f2fs, gfs2, hpfs, fuse, exfat, zonefs, ntfs, ntfs3 and the block device mapping are all converted. No functional changes are intended. This also adds a simple direct I/O path for small reads. On Gen5 NVMe the __iomap_dio_rw() dominates 4K random reads. The same single-core io_uring poll mode workload reaches ~3.2M IOPS against the raw block device but only ~1.92M through ext4 or XFS. __iomap_dio_rw(), iomap_iter(), iomap_dio_bio_iter() and kfree() were at the top of the profile. The new path is very lightweight if no special behavior is requested. The bio comes from a dedicated bioset and laid out so the whole request is a single cacheline aligned allocation. Completion runs inline. That takes ext4 from 1.92M to 2.19M IOPS in the original workload. fio shows around: - 4% at libaio queue depths of 64 and up - around 5% for io_uring - up to 10% for io_uring poll mode at depth 256 on both ext4 and xfs. A few other patches: - iomap_folio_mark_uptodate() lets a filesystem that writes into the page cache outside the iomap read and write paths keep iomap's internal uptodate bitmap in sync, which fuse needs for server-pushed notify stores before it can enable large folios; - two fixes for iomap_bio_read_folio_range_sync(): a potential crash when device integrity behavior is changed and a missing bio_uninit(). - a folio batch release fix on iomap callback failures - FGP_NOFS is dropped from iomap_get_folio() - documentation fix" * tag 'vfs-7.3-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (29 commits) iomap: iomap_bio_read_folio_range_sync is missing a call to bio_uninit iomap: don't free integrity payload that doesn't exist docs: fix grammatical error in iomap docs exfat: convert iomap ops to ->iomap_next() fuse: convert iomap ops to ->iomap_next() hpfs: convert iomap ops to ->iomap_next() gfs2: convert iomap ops to ->iomap_next() f2fs: convert iomap ops to ->iomap_next() block: convert iomap ops to ->iomap_next() ext2: convert iomap ops to ->iomap_next() zonefs: convert iomap ops to ->iomap_next() erofs: convert iomap ops to ->iomap_next() ext4: convert iomap ops to ->iomap_next() ntfs: convert iomap ops to ->iomap_next() ntfs3: convert iomap ops to ->iomap_next() btrfs: convert iomap ops to ->iomap_next() xfs: convert iomap ops to ->iomap_next() iomap: add ->iomap_next() iomap: use GFP_NOWAIT when application for iomap_dio_simple allocations iomap: decouple simple direct I/O reads from iomap_dio_rw ...
2026-07-31iomap: use BIO_COMPLETE_IN_TASK for dropbehind writebackTal Zussman1-4/+1
Set BIO_COMPLETE_IN_TASK on iomap writeback bios when a dropbehind folio is added. This ensures that bi_end_io runs in task context, where folio_end_dropbehind() can safely invalidate folios. With the bio layer now handling task-context deferral generically, IOMAP_IOEND_DONTCACHE is no longer needed, as XFS no longer needs to route DONTCACHE ioends through its completion workqueue. Remove the flag and its NOMERGE entry. Without the NOMERGE, regular I/Os that get merged with a dropbehind folio will also have their completion deferred to task context. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Tal Zussman <tz2294@columbia.edu> Link: https://patch.msgid.link/20260730-blk-dontcache-v7-3-3e8e6850068d@columbia.edu Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-07-31iomap: add ->iomap_next()Joanne Koong1-0/+9
Have one ->iomap_next() callback instead of ->iomap_begin() and ->iomap_end(). ->iomap_next() finishes the previous mapping if needed, and produces the next mapping. Collapsing to a single callback lets a performance-critical caller inline its iteration loop and pass its ->iomap_next() function as a compile-time constant, so the compiler can devirtualize that callback into a direct call instead of an indirect call through a function pointer. iomap_iter() uses ->iomap_next() when the filesystem provides that callback and otherwise falls back to the ->iomap_begin()/->iomap_end() path, so filesystems can be converted one at a time. Suggested-by: Christoph Hellwig <hch@lst.de> Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20260729192737.3190206-6-joannelkoong@gmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-31iomap: decouple simple direct I/O reads from iomap_dio_rwChristoph Hellwig1-0/+66
The pending iomap_iter_next conversion creates performance issues for the new simple direct I/O read fast path, because it assumes a model where the iterator must be advanced at the end, which the direct I/O read fast path tries to avoid. Side step this by splitting the simple path from iomap_dio_rw, and require the file systems to call into it explicitly, and pass only a ->begin callback. This allows to drop various checks for incompatible features while creating a requirement for the file system to only call the simple path for cases that it can handle. As a side-benefit we can now inline the initial part of the simple direct I/O read fast path and let the compiler convert the indirect call to ->begin into a direct call. Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: Fengnan Chang <changfengnan@bytedance.com> Reviewed-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260729192737.3190206-4-joannelkoong@gmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-31iomap: split iomap_iter() logic into iomap_iter_next()Joanne Koong1-17/+85
In preparation for changing iomap to use an in-iter (->iomap_next()) model, move the iomap_iter() logic out into the new iomap_iter_next() helper function. iomap_iter_next() is added as an inlined helper so it can be called directly by ->iomap_next() implementations where the begin()/end() callbacks can be direct calls. The DEFINE_IOMAP_ITER_NEXT() and DEFINE_IOMAP_ITER_NEXT_END() macros are also provided to generate the boilerplate ->iomap_next() wrapper functions that simply forward to iomap_iter_next() with the appropriate begin/end callbacks. DEFINE_IOMAP_ITER_NEXT() is for the common case where there is no end() callback. DEFINE_IOMAP_ITER_NEXT_END() is for the case where there is an explicit end() callback. No functional change intended. The one would-be behavioral difference is that on the iomap_end() error path (ret < 0 && !advanced), the old code returned with iter.status left as the caller's last value whereas the new code zeroes it, but this is not observable in practice as there are no in-tree callers that read iter.status after the iteration loop. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Fengnan Chang <changfengnan@bytedance.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20260729192737.3190206-3-joannelkoong@gmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-31iomap: add helper to mark folio uptodateJoanne Koong1-0/+1
Add an exported helper iomap_folio_mark_uptodate() to mark a folio as uptodate and update its uptodate bitmap if the folio has iomap state data attached. This is needed because there are some filesystems (eg fuse) that have paths outside of conventional iomap calls that need to mark a folio as uptodate (eg writing server-pushed data directly into the page cache) and need the iomap-internal uptodate bitmap to be in sync with the uptodate state of the folio. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20260707220450.1200943-3-joannelkoong@gmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01iomap: consolidate bio submissionChristoph Hellwig1-0/+2
Add a iomap_bio_submit_read_endio helper factored out of iomap_bio_submit_read to that all ->submit_read implementations for iomap_read_ops that use iomap_bio_read_folio_range can shared the logic. Right now that logic is mostly trivial, but already has a bug for XFS because the XFS version is too trivial: file system integrity validation needs a workqueue context and thus can't happen from the default iomap bi_end_io I/O handler. Unfortunately the iomap refactoring just before fs integrity landed moved code around here and the call go misplaced, meaning it never got called. The PI information still is verified by the block layer, but the offloading is less efficient (and the future userspace interface can't get at it). Fixes: 0b10a370529c ("iomap: support T10 protection information") Cc: stable@vger.kernel.org # v7.1 Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260629121750.3392300-2-hch@lst.de Acked-by: Namjae Jeon <linkinjeon@kernel.org> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-05iomap: introduce iomap_fsverity_write() for writing fsverity metadataAndrey Albershteyn1-0/+3
This is just a wrapper around iomap_file_buffered_write() to create necessary iterator over metadata. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org> Link: https://patch.msgid.link/20260520123722.405752-10-aalbersh@kernel.org Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-05iomap: teach iomap to read files with fsverityAndrey Albershteyn1-0/+2
Obtain fsverity info for folios with file data and fsverity metadata. Filesystem can pass vi down to ioend and then to fsverity for verification. This is different from other filesystems ext4, f2fs, btrfs supporting fsverity, these filesystems don't need fsverity_info for reading fsverity metadata. While reading merkle tree iomap requires fsverity info to synthesize hashes for zeroed data block. fsverity metadata has two kinds of holes - ones in merkle tree and one after fsverity descriptor. Merkle tree holes are blocks full of hashes of zeroed data blocks. These are not stored on the disk but synthesized on the fly. This saves a bit of space for sparse files. Due to this iomap also need to lookup fsverity_info for folios with fsverity metadata. ->vi has a hash of the zeroed data block which will be used to fill the merkle tree block. The hole past descriptor is interpreted as end of metadata region. As we don't have EOF here we use this hole as an indication that rest of the folio is empty. This patch marks rest of the folio beyond fsverity descriptor as uptodate. For file data, fsverity needs to verify consistency of the whole file against the root hash, hashes of holes are included in the merkle tree. Verify them too. Issue reading of fsverity merkle tree on the fsverity inodes. This way metadata will be available at I/O completion time. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org> Link: https://patch.msgid.link/20260520123722.405752-9-aalbersh@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-05iomap: introduce IOMAP_F_FSVERITY and teach writeback to handle fsverityAndrey Albershteyn1-0/+8
This flag indicates that I/O is for fsverity metadata. In the write path skip i_size check and i_size updates as metadata is past EOF. In writeback don't update i_size and continue writeback if even folio is beyond EOF. In read path don't zero fsverity folios, again they are past EOF. The iomap_block_needs_zeroing() is also called from write path. For folios of larger order we don't want to zero out pages in the folio as these could contain other merkle tree blocks. For fsverity, filesystem will request to read PAGE_SIZE memory regions. For data folios, iomap will zero the rest of the folio for anything which is beyond EOF. We don't want this for fsverity folios. Christian Brauner <brauner@kernel.org> says: Changed IOMAP_F_FSVERITY from (1U << 10) to (1U << 11) to avoid colliding with IOMAP_F_ZERO_TAIL, which already uses (1U << 10). Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org> Link: https://patch.msgid.link/20260520123722.405752-8-aalbersh@kernel.org Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-05iomap: introduce IOMAP_F_ZERO_TAIL flagNamjae Jeon1-0/+4
In filesystems that maintain a separate Valid Data Length, such as exFAT and NTFS, a partial write may start at or beyond the current valid_size and extend it. In this case, the region after the previous valid_size but within the same filesystem block is considered unwritten. This patch introduces IOMAP_F_ZERO_TAIL. When this flag is set in iomap, __iomap_write_begin() will zero only the tail portion while preserving any valid data before it in the same block. Without this tail zeroing, stale data in the unwritten portion of the block can remain in the page cache. Subsequent reads can then return incorrect contents from that region. Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Link: https://patch.msgid.link/20260518114705.9601-2-linkinjeon@kernel.org Acked-by: "Darrick J. Wong" <djwong@kernel.org> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-05-11iomap: remove over-strict inline data boundary checkNamjae Jeon1-10/+0
The current iomap_inline_data_valid() check ensures that inline data does not cross a PAGE_SIZE boundary. However, this is an unnecessarily strict constraint. If a filesystem provides a valid iomap::inline_data pointer and iomap::length, we should trust that the caller has mapped sufficient memory for the range, even if it spans across page boundaries. Removing this check allows filesystems to point directly to their internal data structures without forced page-alignment or additional redundant allocations. This remove iomap_inline_data_valid() and its callers in buffered and direct I/O paths. Suggested-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Link: https://patch.msgid.link/20260511141151.6021-1-linkinjeon@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-15Merge tag 'mm-stable-2026-04-13-21-45' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "maple_tree: Replace big node with maple copy" (Liam Howlett) Mainly prepararatory work for ongoing development but it does reduce stack usage and is an improvement. - "mm, swap: swap table phase III: remove swap_map" (Kairui Song) Offers memory savings by removing the static swap_map. It also yields some CPU savings and implements several cleanups. - "mm: memfd_luo: preserve file seals" (Pratyush Yadav) File seal preservation to LUO's memfd code - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan Chen) Additional userspace stats reportng to zswap - "arch, mm: consolidate empty_zero_page" (Mike Rapoport) Some cleanups for our handling of ZERO_PAGE() and zero_pfn - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu Han) A robustness improvement and some cleanups in the kmemleak code - "Improve khugepaged scan logic" (Vernon Yang) Improve khugepaged scan logic and reduce CPU consumption by prioritizing scanning tasks that access memory frequently - "Make KHO Stateless" (Jason Miu) Simplify Kexec Handover by transitioning KHO from an xarray-based metadata tracking system with serialization to a radix tree data structure that can be passed directly to the next kernel - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas Ballasi and Steven Rostedt) Enhance vmscan's tracepointing - "mm: arch/shstk: Common shadow stack mapping helper and VM_NOHUGEPAGE" (Catalin Marinas) Cleanup for the shadow stack code: remove per-arch code in favour of a generic implementation - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin) Fix a WARN() which can be emitted the KHO restores a vmalloc area - "mm: Remove stray references to pagevec" (Tal Zussman) Several cleanups, mainly udpating references to "struct pagevec", which became folio_batch three years ago - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl Shutsemau) Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail pages encode their relationship to the head page - "mm/damon/core: improve DAMOS quota efficiency for core layer filters" (SeongJae Park) Improve two problematic behaviors of DAMOS that makes it less efficient when core layer filters are used - "mm/damon: strictly respect min_nr_regions" (SeongJae Park) Improve DAMON usability by extending the treatment of the min_nr_regions user-settable parameter - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka) The proper fix for a previously hotfixed SMP=n issue. Code simplifications and cleanups ensued - "mm: cleanups around unmapping / zapping" (David Hildenbrand) A bunch of cleanups around unmapping and zapping. Mostly simplifications, code movements, documentation and renaming of zapping functions - "support batched checking of the young flag for MGLRU" (Baolin Wang) Batched checking of the young flag for MGLRU. It's part cleanups; one benchmark shows large performance benefits for arm64 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner) memcg cleanup and robustness improvements - "Allow order zero pages in page reporting" (Yuvraj Sakshith) Enhance free page reporting - it is presently and undesirably order-0 pages when reporting free memory. - "mm: vma flag tweaks" (Lorenzo Stoakes) Cleanup work following from the recent conversion of the VMA flags to a bitmap - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae Park) Add some more developer-facing debug checks into DAMON core - "mm/damon: test and document power-of-2 min_region_sz requirement" (SeongJae Park) An additional DAMON kunit test and makes some adjustments to the addr_unit parameter handling - "mm/damon/core: make passed_sample_intervals comparisons overflow-safe" (SeongJae Park) Fix a hard-to-hit time overflow issue in DAMON core - "mm/damon: improve/fixup/update ratio calculation, test and documentation" (SeongJae Park) A batch of misc/minor improvements and fixups for DAMON - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David Hildenbrand) Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code movement was required. - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky) A somewhat random mix of fixups, recompression cleanups and improvements in the zram code - "mm/damon: support multiple goal-based quota tuning algorithms" (SeongJae Park) Extend DAMOS quotas goal auto-tuning to support multiple tuning algorithms that users can select - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao) Fix the khugpaged sysfs handling so we no longer spam the logs with reams of junk when starting/stopping khugepaged - "mm: improve map count checks" (Lorenzo Stoakes) Provide some cleanups and slight fixes in the mremap, mmap and vma code - "mm/damon: support addr_unit on default monitoring targets for modules" (SeongJae Park) Extend the use of DAMON core's addr_unit tunable - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache) Cleanups to khugepaged and is a base for Nico's planned khugepaged mTHP support - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand) Code movement and cleanups in the memhotplug and sparsemem code - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION" (David Hildenbrand) Rationalize some memhotplug Kconfig support - "change young flag check functions to return bool" (Baolin Wang) Cleanups to change all young flag check functions to return bool - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh Law and SeongJae Park) Fix a few potential DAMON bugs - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo Stoakes) Convert a lot of the existing use of the legacy vm_flags_t data type to the new vma_flags_t type which replaces it. Mainly in the vma code. - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes) Expand the mmap_prepare functionality, which is intended to replace the deprecated f_op->mmap hook which has been the source of bugs and security issues for some time. Cleanups, documentation, extension of mmap_prepare into filesystem drivers - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes) Simplify and clean up zap_huge_pmd(). Additional cleanups around vm_normal_folio_pmd() and the softleaf functionality are performed. * tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm: fix deferred split queue races during migration mm/khugepaged: fix issue with tracking lock mm/huge_memory: add and use has_deposited_pgtable() mm/huge_memory: add and use normal_or_softleaf_folio_pmd() mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio() mm/huge_memory: separate out the folio part of zap_huge_pmd() mm/huge_memory: use mm instead of tlb->mm mm/huge_memory: remove unnecessary sanity checks mm/huge_memory: deduplicate zap deposited table call mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE() mm/huge_memory: add a common exit path to zap_huge_pmd() mm/huge_memory: handle buggy PMD entry in zap_huge_pmd() mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc mm/huge: avoid big else branch in zap_huge_pmd() mm/huge_memory: simplify vma_is_specal_huge() mm: on remap assert that input range within the proposed VMA mm: add mmap_action_map_kernel_pages[_full]() uio: replace deprecated mmap hook with mmap_prepare in uio_info drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare mm: allow handling of stacked mmap_prepare hooks in more drivers ...
2026-04-05folio_batch: rename pagevec.h to folio_batch.hTal Zussman1-1/+1
struct pagevec was removed in commit 1e0877d58b1e ("mm: remove struct pagevec"). Rename include/linux/pagevec.h to reflect reality and update includes tree-wide. Add the new filename to MAINTAINERS explicitly, as it no longer matches the "include/linux/page[-_]*" pattern in MEMORY MANAGEMENT - CORE. Link: https://lkml.kernel.org/r/20260225-pagevec_cleanup-v2-3-716868cc2d11@columbia.edu Signed-off-by: Tal Zussman <tz2294@columbia.edu> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Chris Li <chrisl@kernel.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-10iomap: support T10 protection informationChristoph Hellwig1-0/+7
Add support for generating / verifying protection information in iomap. This is done by hooking into the bio submission and then using the generic PI helpers. Compared to just using the block layer auto PI this extends the protection envelope and also prepares for eventually passing through PI from userspace at least for direct I/O. To generate or verify PI, the file system needs to set the IOMAP_F_INTEGRITY flag on the iomap for the request, and ensure the ioends are used for all integrity I/O. Additionally the file system must defer read I/O completions to user context so that the guard tag validation isn't run from interrupt context. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260223132021.292832-16-hch@lst.de Tested-by: Anuj Gupta <anuj20.g@samsung.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-10iomap: add a bioset pointer to iomap_read_folio_opsChristoph Hellwig1-0/+6
Optionally allocate the bio from the bioset provided in iomap_read_folio_ops. If no bioset is provided, fs_bio_set is still used, which is the standard bioset for file systems. Based on a patch from Goldwyn Rodrigues <rgoldwyn@suse.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260223132021.292832-14-hch@lst.de Tested-by: Anuj Gupta <anuj20.g@samsung.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-10iomap: allow file systems to hook into buffered read bio submissionChristoph Hellwig1-0/+4
File systems such as btrfs have additional operations with bios such as verifying data checksums. Allow file systems to hook into submission of the bio to allow for this processing by replacing the direct submit_bio call in iomap_read_alloc_bio with a call into ->submit_read and exporting iomap_read_alloc_bio. Also add a new field to struct iomap_read_folio_ctx to track the file logic offset of the current read context. Based on a patch from Goldwyn Rodrigues <rgoldwyn@suse.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260223132021.292832-12-hch@lst.de Tested-by: Anuj Gupta <anuj20.g@samsung.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-10iomap: pass the iomap_iter to ->submit_readChristoph Hellwig1-1/+2
This provides additional context for file systems. Rename the fuse instance to match the method name while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260223132021.292832-10-hch@lst.de Tested-by: Anuj Gupta <anuj20.g@samsung.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-09Merge tag 'for-7.0/block-stable-pages-20260206' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull bounce buffer dio for stable pages from Jens Axboe: "This adds support for bounce buffering of dio for stable pages. This was all done by Christoph. In his words: This series tries to address the problem that under I/O pages can be modified during direct I/O, even when the device or file system require stable pages during I/O to calculate checksums, parity or data operations. It does so by adding block layer helpers to bounce buffer an iov_iter into a bio, then wires that up in iomap and ultimately XFS. The reason that the file system even needs to know about it, is because reads need a user context to copy the data back, and the infrastructure to defer ioends to a workqueue currently sits in XFS. I'm going to look into moving that into ioend and enabling it for other file systems. Additionally btrfs already has it's own infrastructure for this, and actually an urgent need to bounce buffer, so this should be useful there and could be wire up easily. In fact the idea comes from patches by Qu that did this in btrfs. This patch fixes all but one xfstests failures on T10 PI capable devices (generic/095 seems to have issues with a mix of mmap and splice still, I'm looking into that separately), and make qemu VMs running Windows, or Linux with swap enabled fine on an XFS file on a device using PI. Performance numbers on my (not exactly state of the art) NVMe PI test setup: Sequential reads using io_uring, QD=16. Bandwidth and CPU usage (usr/sys): | size | zero copy | bounce | +------+--------------------------+--------------------------+ | 4k | 1316MiB/s (12.65/55.40%) | 1081MiB/s (11.76/49.78%) | | 64K | 3370MiB/s ( 5.46/18.20%) | 3365MiB/s ( 4.47/15.68%) | | 1M | 3401MiB/s ( 0.76/23.05%) | 3400MiB/s ( 0.80/09.06%) | +------+--------------------------+--------------------------+ Sequential writes using io_uring, QD=16. Bandwidth and CPU usage (usr/sys): | size | zero copy | bounce | +------+--------------------------+--------------------------+ | 4k | 882MiB/s (11.83/33.88%) | 750MiB/s (10.53/34.08%) | | 64K | 2009MiB/s ( 7.33/15.80%) | 2007MiB/s ( 7.47/24.71%) | | 1M | 1992MiB/s ( 7.26/ 9.13%) | 1992MiB/s ( 9.21/19.11%) | +------+--------------------------+--------------------------+ Note that the 64k read numbers look really odd to me for the baseline zero copy case, but are reproducible over many repeated runs. The bounce read numbers should further improve when moving the PI validation to the file system and removing the double context switch, which I have patches for that will sent out soon" * tag 'for-7.0/block-stable-pages-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: xfs: use bounce buffering direct I/O when the device requires stable pages iomap: add a flag to bounce buffer direct I/O iomap: support ioends for direct reads iomap: rename IOMAP_DIO_DIRTY to IOMAP_DIO_USER_BACKED iomap: free the bio before completing the dio iomap: share code between iomap_dio_bio_end_io and iomap_finish_ioend_direct iomap: split out the per-bio logic from iomap_dio_bio_iter iomap: simplify iomap_dio_bio_iter iomap: fix submission side handling of completion side errors block: add helpers to bounce buffer an iov_iter into bios block: remove bio_release_page iov_iter: extract a iov_iter_extract_bvecs helper from bio code block: open code bio_add_page and fix handling of mismatching P2P ranges block: refactor get_contig_folio_len block: add a BIO_MAX_SIZE constant and use it
2026-02-09Merge tag 'vfs-7.0-rc1.iomap' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs iomap updates from Christian Brauner: - Erofs page cache sharing preliminaries: Plumb a void *private parameter through iomap_read_folio() and iomap_readahead() into iomap_iter->private, matching iomap DIO. Erofs uses this to replace a bogus kmap_to_page() call, as preparatory work for page cache sharing. - Fix for invalid folio access: Fix an invalid folio access when a folio without iomap_folio_state is fully submitted to the IO helper — the helper may call folio_end_read() at any time, so ctx->cur_folio must be invalidated after full submission. * tag 'vfs-7.0-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: iomap: fix invalid folio access after folio_end_read() erofs: hold read context in iomap_iter if needed iomap: stash iomap read ctx in the private field of iomap_iter
2026-01-28iomap: add a flag to bounce buffer direct I/OChristoph Hellwig1-0/+9
Add a new flag that request bounce buffering for direct I/O. This is needed to provide the stable pages requirement requested by devices that need to calculate checksums or parity over the data and allows file systems to properly work with things like T10 protection information. The implementation just calls out to the new bio bounce buffering helpers to allocate a bounce buffer, which is used for I/O and to copy to/from it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Tested-by: Anuj Gupta <anuj20.g@samsung.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-14iomap: stash iomap read ctx in the private field of iomap_iterHongbo Li1-4/+4
It's useful to get filesystem-specific information using the existing private field in the @iomap_iter passed to iomap_{begin,end} for advanced usage for iomap buffered reads, which is much like the current iomap DIO. For example, EROFS needs it to: - implement an efficient page cache sharing feature, since iomap needs to apply to anon inode page cache but we'd like to get the backing inode/fs instead, so filesystem-specific private data is needed to keep such information; - pass in both struct page * and void * for inline data to avoid kmap_to_page() usage (which is bogus). Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Link: https://patch.msgid.link/20260109102856.598531-2-lihongbo22@huawei.com Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-12-15iomap: replace folio_batch allocation with stack allocationBrian Foster1-2/+6
Zhang Yi points out that the dynamic folio_batch allocation in iomap_fill_dirty_folios() is problematic for the ext4 on iomap work that is under development because it doesn't sufficiently handle the allocation failure case (by allowing a retry, for example). We've also seen lockdep (via syzbot) complain recently about the scope of the allocation. The dynamic allocation was initially added for simplicity and to help indicate whether the batch was used or not by the calling fs. To address these issues, put the batch on the stack of iomap_zero_range() and use a flag to control whether the batch should be used in the iomap folio lookup path. This keeps things simple and eliminates allocation issues with lockdep and for ext4 on iomap. While here, also clean up the fill helper signature to be more consistent with the underlying filemap helper. Pass through the return value of the filemap helper (folio count) and update the lookup offset via an out param. Fixes: 395ed1ef0012 ("iomap: optional zero range dirty folio processing") Signed-off-by: Brian Foster <bfoster@redhat.com> Link: https://patch.msgid.link/20251208140548.373411-1-bfoster@redhat.com Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-12iomap: simplify ->read_folio_range() error handling for readsJoanne Koong1-3/+2
Instead of requiring that the caller calls iomap_finish_folio_read() even if the ->read_folio_range() callback returns an error, account for this internally in iomap instead, which makes the interface simpler and makes it match writeback's ->read_folio_range() error handling expectations. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20251111193658.3495942-6-joannelkoong@gmail.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-12iomap: optimize pending async writeback accountingJoanne Koong1-2/+0
Pending writebacks must be accounted for to determine when all requests have completed and writeback on the folio should be ended. Currently this is done by atomically incrementing ifs->write_bytes_pending for every range to be written back. Instead, the number of atomic operations can be minimized by setting ifs->write_bytes_pending to the folio size, internally tracking how many bytes are written back asynchronously, and then after sending off all the requests, decrementing ifs->write_bytes_pending by the number of bytes not written back asynchronously. Now, for N ranges written back, only N + 2 atomic operations are required instead of 2N + 2. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20251111193658.3495942-5-joannelkoong@gmail.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-12docs: document iomap writeback's iomap_finish_folio_write() requirementJoanne Koong1-0/+4
Document that iomap_finish_folio_write() must be called after writeback on the range completes. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://patch.msgid.link/20251111193658.3495942-4-joannelkoong@gmail.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05iomap: add IOMAP_DIO_FSBLOCK_ALIGNED flagQu Wenruo1-0/+8
Btrfs requires all of its bios to be fs block aligned, normally it's totally fine but with the incoming block size larger than page size (bs > ps) support, the requirement is no longer met for direct IOs. Because iomap_dio_bio_iter() calls bio_iov_iter_get_pages(), only requiring alignment to be bdev_logical_block_size(). In the real world that value is either 512 or 4K, on 4K page sized systems it means bio_iov_iter_get_pages() can break the bio at any page boundary, breaking btrfs' requirement for bs > ps cases. To address this problem, introduce a new public iomap dio flag, IOMAP_DIO_FSBLOCK_ALIGNED. When calling __iomap_dio_rw() with that new flag, iomap_dio::flags will inherit that new flag, and iomap_dio_bio_iter() will take fs block size into the calculation of the alignment, and pass the alignment to bio_iov_iter_get_pages(), respecting the fs block size requirement. The initial user of this flag will be btrfs, which needs to calculate the checksum for direct read and thus requires the biovec to be fs block aligned for the incoming bs > ps support. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Pankaj Raghav <p.raghav@samsung.com> [hch: also align pos/len, incorporate the trace flags from Darrick] Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20251031131045.1613229-2-hch@lst.de Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05iomap: optional zero range dirty folio processingBrian Foster1-0/+4
The only way zero range can currently process unwritten mappings with dirty pagecache is to check whether the range is dirty before mapping lookup and then flush when at least one underlying mapping is unwritten. This ordering is required to prevent iomap lookup from racing with folio writeback and reclaim. Since zero range can skip ranges of unwritten mappings that are clean in cache, this operation can be improved by allowing the filesystem to provide a set of dirty folios that require zeroing. In turn, rather than flush or iterate file offsets, zero range can iterate on folios in the batch and advance over clean or uncached ranges in between. Add a folio_batch in struct iomap and provide a helper for filesystems to populate the batch at lookup time. Update the folio lookup path to return the next folio in the batch, if provided, and advance the iter if the folio starts beyond the current offset. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05iomap: make iomap_read_folio() a void returnJoanne Koong1-1/+1
No errors are propagated in iomap_read_folio(). Change iomap_read_folio() to a void return to make this clearer to callers. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05iomap: add caller-provided callbacks for read and readaheadJoanne Koong1-2/+61
Add caller-provided callbacks for read and readahead so that it can be used generically, especially by filesystems that are not block-based. In particular, this: * Modifies the read and readahead interface to take in a struct iomap_read_folio_ctx that is publicly defined as: struct iomap_read_folio_ctx { const struct iomap_read_ops *ops; struct folio *cur_folio; struct readahead_control *rac; void *read_ctx; }; where struct iomap_read_ops is defined as: struct iomap_read_ops { int (*read_folio_range)(const struct iomap_iter *iter, struct iomap_read_folio_ctx *ctx, size_t len); void (*read_submit)(struct iomap_read_folio_ctx *ctx); }; read_folio_range() reads in the folio range and is required by the caller to provide. read_submit() is optional and is used for submitting any pending read requests. * Modifies existing filesystems that use iomap for read and readahead to use the new API, through the new statically inlined helpers iomap_bio_read_folio() and iomap_bio_readahead(). There is no change in functionality for those filesystems. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-20iomap: simplify iomap_iter_advance()Joanne Koong1-4/+2
Most callers of iomap_iter_advance() do not need the remaining length returned. Get rid of the extra iomap_length() call that iomap_iter_advance() does. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: add read_folio_range() handler for buffered writesChristoph Hellwig1-0/+10
Add a read_folio_range() handler for buffered writes that filesystems may pass in if they wish to provide a custom handler for synchronously reading in the contents of a folio. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> [hch: renamed to read_folio_range, pass less arguments] Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-14-hch@lst.de Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: replace iomap_folio_ops with iomap_write_opsChristoph Hellwig1-13/+9
The iomap_folio_ops are only used for buffered writes, including the zero and unshare variants. Rename them to iomap_write_ops to better describe the usage, and pass them through the call chain like the other operation specific methods instead of through the iomap. xfs_iomap_valid grows a IOMAP_HOLE check to keep the existing behavior that never attached the folio_ops to a iomap representing a hole. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-12-hch@lst.de Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: export iomap_writeback_folioChristoph Hellwig1-0/+1
Allow fuse to use iomap_writeback_folio for folio laundering. Note that the caller needs to manually submit the pending writeback context. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-11-hch@lst.de Reviewed-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: add public helpers for uptodate state manipulationJoanne Koong1-0/+5
Add a new iomap_start_folio_write helper to abstract away the write_bytes_pending handling, and export it and the existing iomap_finish_folio_write for non-iomap writeback in fuse. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> [hch: split from a larger patch] Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-7-hch@lst.de Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: hide ioends from the generic writeback codeChristoph Hellwig1-10/+9
Replace the ioend pointer in iomap_writeback_ctx with a void *wb_ctx one to facilitate non-block, non-ioend writeback for use. Rename the submit_ioend method to writeback_submit and make it mandatory so that the generic writeback code stops seeing ioends and bios. Co-developed-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-6-hch@lst.de Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: refactor the writeback interfaceChristoph Hellwig1-11/+10
Replace ->map_blocks with a new ->writeback_range, which differs in the following ways: - it must also queue up the I/O for writeback, that is called into the slightly refactored and extended in scope iomap_add_to_ioend for each region - can handle only a part of the requested region, that is the retry loop for partial mappings moves to the caller - handles cleanup on failures as well, and thus also replaces the discard_folio method only implemented by XFS. This will allow to use the iomap writeback code also for file systems that are not block based like fuse. Co-developed-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-5-hch@lst.de Acked-by: Damien Le Moal <dlemoal@kernel.org> # zonefs Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: pass more arguments using the iomap writeback contextChristoph Hellwig1-3/+3
Add inode and wpc fields to pass the inode and writeback context that are needed in the entire writeback call chain, and let the callers initialize all fields in the writeback context before calling iomap_writepages to simplify the argument passing. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-3-hch@lst.de Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-28iomap: don't lose folio dropbehind state for overwritesJens Axboe1-1/+4
DONTCACHE I/O must have the completion punted to a workqueue, just like what is done for unwritten extents, as the completion needs task context to perform the invalidation of the folio(s). However, if writeback is started off filemap_fdatawrite_range() off generic_sync() and it's an overwrite, then the DONTCACHE marking gets lost as iomap_add_to_ioend() don't look at the folio being added and no further state is passed down to help it know that this is a dropbehind/DONTCACHE write. Check if the folio being added is marked as dropbehind, and set IOMAP_IOEND_DONTCACHE if that is the case. Then XFS can factor this into the decision making of completion context in xfs_submit_ioend(). Additionally include this ioend flag in the NOMERGE flags, to avoid mixing it with unrelated IO. Since this is the 3rd flag that will cause XFS to punt the completion to a workqueue, add a helper so that each one of them can get appropriately commented. This fixes extra page cache being instantiated when the write performed is an overwrite, rather than newly instantiated blocks. Fixes: b2cd5ae693a3 ("iomap: make buffered writes work with RWF_DONTCACHE") Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/5153f6e8-274d-4546-bf55-30a5018e0d03@kernel.dk Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-28iomap: Fix conflicting values of iomap flagsRitesh Harjani (IBM)1-8/+7
IOMAP_F_ATOMIC_BIO mistakenly took the same value as of IOMAP_F_SIZE_CHANGED in patch '370a6de7651b ("iomap: rework IOMAP atomic flags")'. Let's fix this and let's also create some more space for filesystem reported flags to avoid this in future. This patch makes the core iomap flags to start from bit 15, moving downwards. Note that "flags" member within struct iomap is of type u16. Fixes: 370a6de7651b ("iomap: rework IOMAP atomic flags") Signed-off-by: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20250327170119.61045-1-ritesh.list@gmail.com Reviewed-by: John Garry <john.g.garry@oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-20iomap: rework IOMAP atomic flagsJohn Garry1-7/+5
Flag IOMAP_ATOMIC_SW is not really required. The idea of having this flag is that the FS ->iomap_begin callback could check if this flag is set to decide whether to do a SW (FS-based) atomic write. But the FS can set which ->iomap_begin callback it wants when deciding to do a FS-based atomic write. Furthermore, it was thought that IOMAP_ATOMIC_HW is not a proper name, as the block driver can use SW-methods to emulate an atomic write. So change back to IOMAP_ATOMIC. The ->iomap_begin callback needs though to indicate to iomap core that REQ_ATOMIC needs to be set, so add IOMAP_F_ATOMIC_BIO for that. These changes were suggested by Christoph Hellwig and Dave Chinner. Signed-off-by: John Garry <john.g.garry@oracle.com> Link: https://lore.kernel.org/r/20250320120250.4087011-4-john.g.garry@oracle.com Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-06iomap: Support SW-based atomic writesJohn Garry1-1/+7
Currently atomic write support requires dedicated HW support. This imposes a restriction on the filesystem that disk blocks need to be aligned and contiguously mapped to FS blocks to issue atomic writes. XFS has no method to guarantee FS block alignment for regular, non-RT files. As such, atomic writes are currently limited to 1x FS block there. To deal with the scenario that we are issuing an atomic write over misaligned or discontiguous data blocks - and raise the atomic write size limit - support a SW-based software emulated atomic write mode. For XFS, this SW-based atomic writes would use CoW support to issue emulated untorn writes. It is the responsibility of the FS to detect discontiguous atomic writes and switch to IOMAP_DIO_ATOMIC_SW mode and retry the write. Indeed, SW-based atomic writes could be used always when the mounted bdev does not support HW offload, but this strategy is not initially expected to be used. Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: John Garry <john.g.garry@oracle.com> Link: https://lore.kernel.org/r/20250303171120.2837067-6-john.g.garry@oracle.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-06iomap: Rename IOMAP_ATOMIC -> IOMAP_ATOMIC_HWJohn Garry1-1/+1
In future xfs will support a SW-based atomic write, so rename IOMAP_ATOMIC -> IOMAP_ATOMIC_HW to be clear which mode is being used. Also relocate setting of IOMAP_ATOMIC_HW to the write path in __iomap_dio_rw(), to be clear that this flag is only relevant to writes. Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: John Garry <john.g.garry@oracle.com> Link: https://lore.kernel.org/r/20250303171120.2837067-3-john.g.garry@oracle.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-06Merge branch 'vfs-6.15.shared.iomap' of ↵Christian Brauner1-0/+1
gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Bring in iomap changes that xfs relies on. Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-27iomap: make buffered writes work with RWF_DONTCACHEJens Axboe1-0/+1
Add iomap buffered write support for RWF_DONTCACHE. If RWF_DONTCACHE is set for a write, mark the folios being written as uncached. Then writeback completion will drop the pages. The write_iter handler simply kicks off writeback for the pages, and writeback completion will take care of the rest. Signed-off-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20250204184047.356762-2-axboe@kernel.dk Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-26iomap: introduce a full map advance helperBrian Foster1-0/+10
Various iomap_iter_advance() calls advance by the full mapping length and thus have no need for the current length input or post-advance remaining length output from the standard advance function. Add an iomap_iter_advance_full() helper to clean up these cases. Signed-off-by: Brian Foster <bfoster@redhat.com> Link: https://lore.kernel.org/r/20250224144757.237706-13-bfoster@redhat.com Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-26iomap: rename iomap_iter processed field to statusBrian Foster1-4/+3
The iter.processed field name is no longer appropriate now that iomap operations do not return the number of bytes processed. Rename the field to iter.status to reflect that a success or error code is expected. Also change the type to int as there is no longer a need for an s64. This reduces the size of iomap_iter by 8 bytes due to a combination of smaller type and reduction in structure padding. While here, fix up the return types of various _iter() helpers to reflect the type change. Signed-off-by: Brian Foster <bfoster@redhat.com> Link: https://lore.kernel.org/r/20250224144757.237706-12-bfoster@redhat.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-10iomap: support incremental iomap_iter advancesBrian Foster1-2/+6
The current iomap_iter iteration model reads the mapping from the filesystem, processes the subrange of the operation associated with the current mapping, and returns the number of bytes processed back to the iteration code. The latter advances the position and remaining length of the iter in preparation for the next iteration. At the _iter() handler level, this tends to produce a processing loop where the local code pulls the current position and remaining length out of the iter, iterates it locally based on file offset, and then breaks out when the associated range has been fully processed. This works well enough for current handlers, but upcoming enhancements require a bit more flexibility in certain situations. Enhancements for zero range will lead to a situation where the processing loop is no longer a pure ascending offset walk, but rather dictated by pagecache state and folio lookup. Since folio lookup and write preparation occur at different levels, it is more difficult to manage position and length outside of the iter. To provide more flexibility to certain iomap operations, introduce support for incremental iomap_iter advances from within the operation itself. This allows more granular advances for operations that might not use the typical file offset based walk. Note that the semantics for operations that use incremental advances is slightly different than traditional operations. Operations that advance the iter directly are expected to return success or failure (i.e. 0 or negative error code) in iter.processed rather than the number of bytes processed. Signed-off-by: Brian Foster <bfoster@redhat.com> Link: https://lore.kernel.org/r/20250207143253.314068-8-bfoster@redhat.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-10iomap: export iomap_iter_advance() and return remaining lengthBrian Foster1-0/+1
As a final step for generic iter advance, export the helper and update it to return the remaining length of the current iteration after the advance. This will usually be 0 in the iomap_iter() case, but will be useful for the various operations that iterate on their own and will be updated to advance as they progress. Signed-off-by: Brian Foster <bfoster@redhat.com> Link: https://lore.kernel.org/r/20250207143253.314068-7-bfoster@redhat.com Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>