linux.git/include/linux/iomap.h, branch v7.3-rc2

Merge tag 'for-7.3/block-20260819' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

2026-08-20T20:55:16+00:00

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
  ...

Merge tag 'vfs-7.3-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-08-17T17:03:55+00:00

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
  ...

iomap: use BIO_COMPLETE_IN_TASK for dropbehind writeback

2026-07-31T15:00:14+00:00

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 
Signed-off-by: Tal Zussman 
Link: https://patch.msgid.link/20260730-blk-dontcache-v7-3-3e8e6850068d@columbia.edu
Signed-off-by: Jens Axboe

iomap: add ->iomap_next()

2026-07-31T10:28:49+00:00

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 
Suggested-by: Matthew Wilcox (Oracle) 
Reviewed-by: "Darrick J. Wong" 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Joanne Koong 
Link: https://patch.msgid.link/20260729192737.3190206-6-joannelkoong@gmail.com
Signed-off-by: Christian Brauner (Amutable)

iomap: decouple simple direct I/O reads from iomap_dio_rw

2026-07-31T10:28:49+00:00

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" 
Reviewed-by: Fengnan Chang 
Reviewed-by: Joanne Koong 
Signed-off-by: Joanne Koong 
Signed-off-by: Christoph Hellwig 
Link: https://patch.msgid.link/20260729192737.3190206-4-joannelkoong@gmail.com
Signed-off-by: Christian Brauner (Amutable)

iomap: split iomap_iter() logic into iomap_iter_next()

2026-07-31T10:28:48+00:00

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 
Reviewed-by: Fengnan Chang 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Joanne Koong 
Link: https://patch.msgid.link/20260729192737.3190206-3-joannelkoong@gmail.com
Signed-off-by: Christian Brauner (Amutable)

iomap: add helper to mark folio uptodate

2026-07-31T10:28:46+00:00

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 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Joanne Koong 
Link: https://patch.msgid.link/20260707220450.1200943-3-joannelkoong@gmail.com
Signed-off-by: Christian Brauner (Amutable)

iomap: consolidate bio submission

2026-07-01T13:26:47+00:00

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 
Link: https://patch.msgid.link/20260629121750.3392300-2-hch@lst.de
Acked-by: Namjae Jeon 
Reviewed-by: "Darrick J. Wong" 
Reviewed-by: Joanne Koong 
Signed-off-by: Christian Brauner (Amutable)

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)