kernel/linux.git/include/linux/iomap.h, branch v7.2-rc1

iomap: introduce iomap_fsverity_write() for writing fsverity metadata

2026-06-05T11:36:22+00:00

This is just a wrapper around iomap_file_buffered_write() to create necessary iterator over metadata. Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Andrey Albershteyn Link: https://patch.msgid.link/20260520123722.405752-10-aalbersh@kernel.org Reviewed-by: "Darrick J. Wong" Signed-off-by: Christian Brauner (Amutable)

iomap: teach iomap to read files with fsverity

2026-06-05T11:36:22+00:00

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 Reviewed-by: Christoph Hellwig Signed-off-by: Andrey Albershteyn Link: https://patch.msgid.link/20260520123722.405752-9-aalbersh@kernel.org Signed-off-by: Christian Brauner (Amutable)

iomap: introduce IOMAP_F_FSVERITY and teach writeback to handle fsverity

2026-06-05T11:36:22+00:00

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 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 Link: https://patch.msgid.link/20260520123722.405752-8-aalbersh@kernel.org Reviewed-by: "Darrick J. Wong" Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner (Amutable)

iomap: introduce IOMAP_F_ZERO_TAIL flag

2026-06-05T08:30:00+00:00

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 Signed-off-by: Namjae Jeon Link: https://patch.msgid.link/20260518114705.9601-2-linkinjeon@kernel.org Acked-by: "Darrick J. Wong" Reviewed-by: "Darrick J. Wong" Signed-off-by: Christian Brauner (Amutable)

iomap: remove over-strict inline data boundary check

2026-05-11T14:56:53+00:00

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 Reviewed-by: Christoph Hellwig Reviewed-by: Gao Xiang Signed-off-by: Namjae Jeon Link: https://patch.msgid.link/20260511141151.6021-1-linkinjeon@kernel.org Signed-off-by: Christian Brauner

Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-04-15T19:59:16+00:00

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 ...

folio_batch: rename pagevec.h to folio_batch.h

2026-04-05T20:53:07+00:00

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 Acked-by: David Hildenbrand (Arm) Reviewed-by: Jan Kara Acked-by: Zi Yan Reviewed-by: Lorenzo Stoakes (Oracle) Cc: Chris Li Cc: Christian Brauner Cc: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton

iomap: support T10 protection information

2026-03-10T09:29:17+00:00

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 Link: https://patch.msgid.link/20260223132021.292832-16-hch@lst.de Tested-by: Anuj Gupta Reviewed-by: "Darrick J. Wong" Signed-off-by: Christian Brauner

iomap: add a bioset pointer to iomap_read_folio_ops

2026-03-10T09:29:03+00:00

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 . Signed-off-by: Christoph Hellwig Link: https://patch.msgid.link/20260223132021.292832-14-hch@lst.de Tested-by: Anuj Gupta Reviewed-by: "Darrick J. Wong" Signed-off-by: Christian Brauner

iomap: allow file systems to hook into buffered read bio submission

2026-03-10T09:29:03+00:00

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 . Signed-off-by: Christoph Hellwig Link: https://patch.msgid.link/20260223132021.292832-12-hch@lst.de Tested-by: Anuj Gupta Reviewed-by: "Darrick J. Wong" Signed-off-by: Christian Brauner