Pull iomap updates from Christian Brauner:
- Add the vfs infrastructure required to implement fs-verity support
for XFS with a post-EOF merkle tree: fsverity generates and stores a
zero-block hash, and iomap learns to verify data on buffered reads,
to handle fsverity during writeback via the new IOMAP_F_FSVERITY
flag, and to write fsverity metadata through iomap_fsverity_write().
- Skip the memset of the iomap in iomap_iter() once the iteration is
done. In high-IOPS scenarios (4k randread NVMe polling via io_uring)
the pointless memset wasted memory write bandwidth; this improves
IOPS by about 5% on ext4 and xfs.
- Add balance_dirty_pages_ratelimited() to iomap_zero_iter(), aligning
it with iomap_write_iter(). This prepares for the exFAT iomap
conversion where zeroing beyond valid_size can trigger large-scale
zeroing operations that caused memory pressure without throttling.
- Remove the over-strict inline data boundary check. If a filesystem
provides a valid inline_data pointer and length there is no reason to
require that inline data must not cross a page boundary.
- Don't make REQ_POLLED imply REQ_NOWAIT, matching the earlier
equivalent block layer fix: there are valid cases to poll for I/O
completion without REQ_NOWAIT, and REQ_NOWAIT for file system writes
is currently not supported as writes aren't idempotent.
- Introduce IOMAP_F_ZERO_TAIL for filesystems that maintain a separate
valid data length (exFAT, NTFS). For a write starting at or beyond
valid_size, __iomap_write_begin() now zeroes only the tail portion of
the block while preserving valid data before it, instead of leaving
stale data in the page cache. The flag is also added to the iomap
trace event strings.
* tag 'vfs-7.2-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
iomap: Add IOMAP_F_ZERO_TAIL flag to trace event strings
iomap: introduce iomap_fsverity_write() for writing fsverity metadata
iomap: teach iomap to read files with fsverity
iomap: introduce IOMAP_F_FSVERITY and teach writeback to handle fsverity
fsverity: generate and store zero-block hash
iomap: introduce IOMAP_F_ZERO_TAIL flag
iomap: don't make REQ_POLLED imply REQ_NOWAIT
iomap: remove over-strict inline data boundary check
iomap: add dirty page control to iomap_zero_iter
iomap: avoid memset iomap when iter is done
As described in commit 2bc0576925 ("block: don't make REQ_POLLED imply
REQ_NOWAIT"), which fixed the same issue for the block device node, there
are valid cases to poll for I/O completion without REQ_NOWAIT.
Additionally, sing REQ_NOWAIT for file system writes is currently not
supported as file systems writes are not idempotent and would need a
retry of just the bio and not the entire operation to be fully supported.
Switch iomap to set REQ_POLLED and remove the now unused bio_set_polled
helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260518062917.506483-1-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
When bouncing for block size > PAGE_SIZE file systems that require
file system block size alignment (e.g. zoned XFS), the bio needs to
be big enough to fit an entire block.
Fixes: 8dd5e7c75d ("block: add helpers to bounce buffer an iov_iter into bios")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260507050153.1298375-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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>
Pull fscrypt updates from Eric Biggers:
- Various cleanups for the interface between fs/crypto/ and
filesystems, from Christoph Hellwig
- Simplify and optimize the implementation of v1 key derivation by
using the AES library instead of the crypto_skcipher API
* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux:
fscrypt: use AES library for v1 key derivation
ext4: use a byte granularity cursor in ext4_mpage_readpages
fscrypt: pass a real sector_t to fscrypt_zeroout_range
fscrypt: pass a byte length to fscrypt_zeroout_range
fscrypt: pass a byte offset to fscrypt_zeroout_range
fscrypt: pass a byte length to fscrypt_zeroout_range_inline_crypt
fscrypt: pass a byte offset to fscrypt_zeroout_range_inline_crypt
fscrypt: pass a byte offset to fscrypt_set_bio_crypt_ctx
fscrypt: pass a byte offset to fscrypt_mergeable_bio
fscrypt: pass a byte offset to fscrypt_generate_dun
fscrypt: move fscrypt_set_bio_crypt_ctx_bh to buffer.c
ext4, fscrypt: merge fscrypt_mergeable_bio_bh into io_submit_need_new_bio
ext4: factor out a io_submit_need_new_bio helper
ext4: open code fscrypt_set_bio_crypt_ctx_bh
ext4: initialize the write hint in io_submit_init_bio
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>
Bring in the shared branch with the block layer.
* 'for-7.1/block-integrity' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
block: pass a maxlen argument to bio_iov_iter_bounce
block: add fs_bio_integrity helpers
block: make max_integrity_io_size public
block: prepare generation / verification helpers for fs usage
block: add a bdev_has_integrity_csum helper
block: factor out a bio_integrity_setup_default helper
block: factor out a bio_integrity_action helper
Signed-off-by: Christian Brauner <brauner@kernel.org>
Allow the file system to limit the size processed in a single
bounce operation. This is needed when generating integrity data
so that the size of a single integrity segment can't overflow.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Tested-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
iomap's directio implementation has two magic errno codes that it uses
to signal callers -- ENOTBLK tells the filesystem that it should retry
a write with the pagecache; and EAGAIN tells the caller that pagecache
flushing or invalidation failed and that it should try again.
Neither of these indicate data loss, so let's not report them.
Fixes: a9d573ee88 ("iomap: report file I/O errors to the VFS")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://patch.msgid.link/20260224154637.GD2390381@frogsfrogsfrogs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
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
Pull block updates from Jens Axboe:
- Support for batch request processing for ublk, improving the
efficiency of the kernel/ublk server communication. This can yield
nice 7-12% performance improvements
- Support for integrity data for ublk
- Various other ublk improvements and additions, including a ton of
selftests additions and updated
- Move the handling of blk-crypto software fallback from below the
block layer to above it. This reduces the complexity of dealing with
bio splitting
- Series fixing a number of potential deadlocks in blk-mq related to
the queue usage counter and writeback throttling and rq-qos debugfs
handling
- Add an async_depth queue attribute, to resolve a performance
regression that's been around for a qhilw related to the scheduler
depth handling
- Only use task_work for IOPOLL completions on NVMe, if it is necessary
to do so. An earlier fix for an issue resulted in all these
completions being punted to task_work, to guarantee that completions
were only run for a given io_uring ring when it was local to that
ring. With the new changes, we can detect if it's necessary to use
task_work or not, and avoid it if possible.
- rnbd fixes:
- Fix refcount underflow in device unmap path
- Handle PREFLUSH and NOUNMAP flags properly in protocol
- Fix server-side bi_size for special IOs
- Zero response buffer before use
- Fix trace format for flags
- Add .release to rnbd_dev_ktype
- MD pull requests via Yu Kuai
- Fix raid5_run() to return error when log_init() fails
- Fix IO hang with degraded array with llbitmap
- Fix percpu_ref not resurrected on suspend timeout in llbitmap
- Fix GPF in write_page caused by resize race
- Fix NULL pointer dereference in process_metadata_update
- Fix hang when stopping arrays with metadata through dm-raid
- Fix any_working flag handling in raid10_sync_request
- Refactor sync/recovery code path, improve error handling for
badblocks, and remove unused recovery_disabled field
- Consolidate mddev boolean fields into mddev_flags
- Use mempool to allocate stripe_request_ctx and make sure
max_sectors is not less than io_opt in raid5
- Fix return value of mddev_trylock
- Fix memory leak in raid1_run()
- Add Li Nan as mdraid reviewer
- Move phys_vec definitions to the kernel types, mostly in preparation
for some VFIO and RDMA changes
- Improve the speed for secure erase for some devices
- Various little rust updates
- Various other minor fixes, improvements, and cleanups
* tag 'for-7.0/block-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (162 commits)
blk-mq: ABI/sysfs-block: fix docs build warnings
selftests: ublk: organize test directories by test ID
block: decouple secure erase size limit from discard size limit
block: remove redundant kill_bdev() call in set_blocksize()
blk-mq: add documentation for new queue attribute async_dpeth
block, bfq: convert to use request_queue->async_depth
mq-deadline: covert to use request_queue->async_depth
kyber: covert to use request_queue->async_depth
blk-mq: add a new queue sysfs attribute async_depth
blk-mq: factor out a helper blk_mq_limit_depth()
blk-mq-sched: unify elevators checking for async requests
block: convert nr_requests to unsigned int
block: don't use strcpy to copy blockdev name
blk-mq-debugfs: warn about possible deadlock
blk-mq-debugfs: add missing debugfs_mutex in blk_mq_debugfs_register_hctxs()
blk-mq-debugfs: remove blk_mq_debugfs_unregister_rqos()
blk-mq-debugfs: make blk_mq_debugfs_register_rqos() static
blk-rq-qos: fix possible debugfs_mutex deadlock
blk-mq-debugfs: factor out a helper to register debugfs for all rq_qos
blk-wbt: fix possible deadlock to nest pcpu_alloc_mutex under q_usage_counter
...
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>
Match the more descriptive iov_iter terminology instead of encoding
what we do with them for reads only.
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>
There are good arguments for processing the user completions ASAP vs.
freeing resources ASAP, but freeing the bio first here removes potential
use after free hazards when checking flags, and will simplify the
upcoming bounce buffer support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Tested-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use iov_iter_count to check if we need to continue as that just reads
a field in the iov_iter, and only use bio_iov_vecs_to_alloc to calculate
the actual number of vectors to allocate for the bio.
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>
The "if (dio->error)" in iomap_dio_bio_iter exists to stop submitting
more bios when a completion already return an error. Commit cfe057f7db
("iomap_dio_actor(): fix iov_iter bugs") made it revert the iov by
"copied", which is very wrong given that we've already consumed that
range and submitted a bio for it.
Fixes: cfe057f7db ("iomap_dio_actor(): fix iov_iter bugs")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a blk_crypto_submit_bio helper that either submits the bio when
it is not encrypted or inline encryption is provided, but otherwise
handles the encryption before going down into the low-level driver.
This reduces the risk from bio reordering and keeps memory allocation
as high up in the stack as possible.
Note that if the submitter knows that inline enctryption is known to
be supported by the underyling driver, it can still use plain
submit_bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull misc vfs updates from Christian Brauner:
"Features:
- Cheaper MAY_EXEC handling for path lookup. This elides MAY_WRITE
permission checks during path lookup and adds the
IOP_FASTPERM_MAY_EXEC flag so filesystems like btrfs can avoid
expensive permission work.
- Hide dentry_cache behind runtime const machinery.
- Add German Maglione as virtiofs co-maintainer.
Cleanups:
- Tidy up and inline step_into() and walk_component() for improved
code generation.
- Re-enable IOCB_NOWAIT writes to files. This refactors file
timestamp update logic, fixing a layering bypass in btrfs when
updating timestamps on device files and improving FMODE_NOCMTIME
handling in VFS now that nfsd started using it.
- Path lookup optimizations extracting slowpaths into dedicated
routines and adding branch prediction hints for mntput_no_expire(),
fd_install(), lookup_slow(), and various other hot paths.
- Enable clang's -fms-extensions flag, requiring a JFS rename to
avoid conflicts.
- Remove spurious exports in fs/file_attr.c.
- Stop duplicating union pipe_index declaration. This depends on the
shared kbuild branch that brings in -fms-extensions support which
is merged into this branch.
- Use MD5 library instead of crypto_shash in ecryptfs.
- Use largest_zero_folio() in iomap_dio_zero().
- Replace simple_strtol/strtoul with kstrtoint/kstrtouint in init and
initrd code.
- Various typo fixes.
Fixes:
- Fix emergency sync for btrfs. Btrfs requires an explicit sync_fs()
call with wait == 1 to commit super blocks. The emergency sync path
never passed this, leaving btrfs data uncommitted during emergency
sync.
- Use local kmap in watch_queue's post_one_notification().
- Add hint prints in sb_set_blocksize() for LBS dependency on THP"
* tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits)
MAINTAINERS: add German Maglione as virtiofs co-maintainer
fs: inline step_into() and walk_component()
fs: tidy up step_into() & friends before inlining
orangefs: use inode_update_timestamps directly
btrfs: fix the comment on btrfs_update_time
btrfs: use vfs_utimes to update file timestamps
fs: export vfs_utimes
fs: lift the FMODE_NOCMTIME check into file_update_time_flags
fs: refactor file timestamp update logic
include/linux/fs.h: trivial fix: regualr -> regular
fs/splice.c: trivial fix: pipes -> pipe's
fs: mark lookup_slow() as noinline
fs: add predicts based on nd->depth
fs: move mntput_no_expire() slowpath into a dedicated routine
fs: remove spurious exports in fs/file_attr.c
watch_queue: Use local kmap in post_one_notification()
fs: touch up predicts in path lookup
fs: move fd_install() slowpath into a dedicated routine and provide commentary
fs: hide dentry_cache behind runtime const machinery
fs: touch predicts in do_dentry_open()
...
Replace IOMAP_DIO_INLINE_COMP with a flag to indicate that the
completion should be offloaded. This removes a tiny bit of boilerplate
code, but more importantly just makes the code easier to follow as this
new flag gets set most of the time and only cleared in one place, while
it was the inverse for the old version.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251113170633.1453259-6-hch@lst.de
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Completions for pure overwrites don't need to be deferred to a workqueue
as there is no work to be done, or at least no work that needs a user
context. Set the IOMAP_DIO_INLINE_COMP by default for writes like we
already do for reads, and the clear it for all the cases that actually
do need a user context for completions to update the inode size or
record updates to the logical to physical mapping.
I've audited all users of the ->end_io callback, and they only require
user context for I/O that involves unwritten extents, COW, size
extensions, or error handling and all those are still run from workqueue
context.
This restores the behavior of the old pre-iomap direct I/O code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251113170633.1453259-5-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
The way how iomap_dio_can_use_fua and the caller is structured is
a bit confusing, as the main guarding condition is hidden in the
helper, and the secondary conditions are split between caller and
callee.
Refactor the code, so that iomap_dio_bio_iter itself tracks if a write
might need metadata updates based on the iomap type and flags, and
then have a condition based on that to use the FUA flag.
Note that this also moves the REQ_OP_WRITE assignment to the end of
the branch to improve readability a bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20251113170633.1453259-4-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
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>
iomap_dio_zero() uses a custom allocated memory of zeroes for padding
zeroes. This was a temporary solution until there was a way to request a
zero folio that was greater than the PAGE_SIZE.
Use largest_zero_folio() function instead of using the custom allocated
memory of zeroes. There is no guarantee from largest_zero_folio()
function that it will always return a PMD sized folio. Adapt the code so
that it can also work if largest_zero_folio() returns a ZERO_PAGE.
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
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>
Pull block updates from Jens Axboe:
- NVMe pull request via Keith:
- FC target fixes (Daniel)
- Authentication fixes and updates (Martin, Chris)
- Admin controller handling (Kamaljit)
- Target lockdep assertions (Max)
- Keep-alive updates for discovery (Alastair)
- Suspend quirk (Georg)
- MD pull request via Yu:
- Add support for a lockless bitmap.
A key feature for the new bitmap are that the IO fastpath is
lockless. If a user issues lots of write IO to the same bitmap
bit in a short time, only the first write has additional overhead
to update bitmap bit, no additional overhead for the following
writes.
By supporting only resync or recover written data, means in the
case creating new array or replacing with a new disk, there is no
need to do a full disk resync/recovery.
- Switch ->getgeo() and ->bios_param() to using struct gendisk rather
than struct block_device.
- Rust block changes via Andreas. This series adds configuration via
configfs and remote completion to the rnull driver. The series also
includes a set of changes to the rust block device driver API: a few
cleanup patches, and a few features supporting the rnull changes.
The series removes the raw buffer formatting logic from
`kernel::block` and improves the logic available in `kernel::string`
to support the same use as the removed logic.
- floppy arch cleanups
- Reduce the number of dereferencing needed for ublk commands
- Restrict supported sockets for nbd. Mostly done to eliminate a class
of issues perpetually reported by syzbot, by using nonsensical socket
setups.
- A few s390 dasd block fixes
- Fix a few issues around atomic writes
- Improve DMA interation for integrity requests
- Improve how iovecs are treated with regards to O_DIRECT aligment
constraints.
We used to require each segment to adhere to the constraints, now
only the request as a whole needs to.
- Clean up and improve p2p support, enabling use of p2p for metadata
payloads
- Improve locking of request lookup, using SRCU where appropriate
- Use page references properly for brd, avoiding very long RCU sections
- Fix ordering of recursively submitted IOs
- Clean up and improve updating nr_requests for a live device
- Various fixes and cleanups
* tag 'for-6.18/block-20250929' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (164 commits)
s390/dasd: enforce dma_alignment to ensure proper buffer validation
s390/dasd: Return BLK_STS_INVAL for EINVAL from do_dasd_request
ublk: remove redundant zone op check in ublk_setup_iod()
nvme: Use non zero KATO for persistent discovery connections
nvmet: add safety check for subsys lock
nvme-core: use nvme_is_io_ctrl() for I/O controller check
nvme-core: do ioccsz/iorcsz validation only for I/O controllers
nvme-core: add method to check for an I/O controller
blk-cgroup: fix possible deadlock while configuring policy
blk-mq: fix null-ptr-deref in blk_mq_free_tags() from error path
blk-mq: Fix more tag iteration function documentation
selftests: ublk: fix behavior when fio is not installed
ublk: don't access ublk_queue in ublk_unmap_io()
ublk: pass ublk_io to __ublk_complete_rq()
ublk: don't access ublk_queue in ublk_need_complete_req()
ublk: don't access ublk_queue in ublk_check_commit_and_fetch()
ublk: don't pass ublk_queue to ublk_fetch()
ublk: don't access ublk_queue in ublk_config_io_buf()
ublk: don't access ublk_queue in ublk_check_fetch_buf()
ublk: pass q_id and tag to __ublk_check_and_get_req()
...
Pull vfs iomap updates from Christian Brauner:
"This contains minor fixes and cleanups to the iomap code.
Nothing really stands out here"
* tag 'vfs-6.18-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
iomap: error out on file IO when there is no inline_data buffer
iomap: trace iomap_zero_iter zeroing activities
The block layer checks all the segments for validity later, so no need
for an early check. Just reduce it to a simple position and total length
check, and defer the more invasive segment checks to the block layer.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The block layer tries to align bio vectors to the block device's logical
block size. Some cases don't have a block device, or we may need to
align to something larger, which we can't derive it from the queue
limits. Have the caller specify what they want, or allow any length
alignment if nothing was specified. Since the most common use case
relies on the block device's limits, a helper function is provided.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit d279c80e0b ("iomap: inline iomap_dio_bio_opflags()") has broken
the logic in iomap_dio_bio_iter() in a way that when the device does
support FUA (or has no writeback cache) and the direct IO happens to
freshly allocated or unwritten extents, we will *not* issue fsync after
completing direct IO O_SYNC / O_DSYNC write because the
IOMAP_DIO_WRITE_THROUGH flag stays mistakenly set. Fix the problem by
clearing IOMAP_DIO_WRITE_THROUGH whenever we do not perform FUA write as
it was originally intended.
CC: John Garry <john.g.garry@oracle.com>
CC: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Fixes: d279c80e0b ("iomap: inline iomap_dio_bio_opflags()")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/20250730102840.20470-2-jack@suse.cz
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull vfs iomap updates from Christian Brauner:
- Allow the filesystem to submit the writeback bios.
- Allow the filsystem to track completions on a per-bio bases
instead of the entire I/O.
- Change writeback_ops so that ->submit_bio can be done by the
filesystem.
- A new ANON_WRITE flag for writes that don't have a block number
assigned to them at the iomap level leaving the filesystem to do
that work in the submission handler.
- Incremental iterator advance
The folio_batch support for zero range where the filesystem provides
a batch of folios to process that might not be logically continguous
requires more flexibility than the current offset based iteration
currently offers.
Update all iomap operations to advance the iterator within the
operation and thus remove the need to advance from the core iomap
iterator.
- Make buffered writes work with RWF_DONTCACHE
If RWF_DONTCACHE is set for a write, mark the folios being written as
uncached. On writeback completion the pages will be dropped.
- Introduce infrastructure for large atomic writes
This will eventually be used by xfs and ext4.
* tag 'vfs-6.15-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (42 commits)
iomap: rework IOMAP atomic flags
iomap: comment on atomic write checks in iomap_dio_bio_iter()
iomap: inline iomap_dio_bio_opflags()
iomap: fix inline data on buffered read
iomap: Lift blocksize restriction on atomic writes
iomap: Support SW-based atomic writes
iomap: Rename IOMAP_ATOMIC -> IOMAP_ATOMIC_HW
xfs: flag as supporting FOP_DONTCACHE
iomap: make buffered writes work with RWF_DONTCACHE
iomap: introduce a full map advance helper
iomap: rename iomap_iter processed field to status
iomap: remove unnecessary advance from iomap_iter()
dax: advance the iomap_iter on pte and pmd faults
dax: advance the iomap_iter on dedupe range
dax: advance the iomap_iter on unshare range
dax: advance the iomap_iter on zero range
dax: push advance down into dax_iomap_iter() for read and write
dax: advance the iomap_iter in the read/write path
iomap: convert misc simple ops to incremental advance
iomap: advance the iter on direct I/O
...
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>
Filesystems like ext4 can submit writes in multiples of blocksizes.
But we still can't allow the writes to be split. Hence let's check if
the iomap_length() is same as iter->len or not.
It is the role of the FS to ensure that a single mapping may be created
for an atomic write. The FS will also continue to check size and alignment
legality.
Signed-off-by: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
jpg: Tweak commit message
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20250303171120.2837067-7-john.g.garry@oracle.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
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>
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>
