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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
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git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
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
...
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Add helpers to implement bounce buffering of data into a bio to implement
direct I/O for cases where direct user access is not possible because
stable in-flight data is required. These are intended to be used as
easily as bio_iov_iter_get_pages for the zero-copy path.
The write side is trivial and just copies data into the bounce buffer.
The read side is a lot more complex because it needs to perform the copy
from the completion context, and without preserving the iov_iter through
the call chain. It steals a trick from the integrity data user interface
and uses the first vector in the bio for the bounce buffer data that is
fed to the block I/O stack, and uses the others to record the user
buffer fragments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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There are no more callers of this function after commit f6b2d8b134b2413
("btrfs: track the next file offset in struct btrfs_bio_ctrl"), so
remove the function.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Add a helper to allow an existing bio to be resubmitted without
having to re-add the payload.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
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We'll need bio_flagged() earlier in bio.h for later patches, move it
together with all related helpers, and mark the bio_flagged()'s bio
argument as const.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The blk-mq dma iterator has an optimization for requests that align to
the device's iommu merge boundary. This boundary may be larger than the
device's virtual boundary, but the code had been depending on that queue
limit to know ahead of time if the request is guaranteed to align to
that optimization.
Rather than rely on that queue limit, which many devices may not report,
save the lowest set bit of any boundary gap between each segment in the
bio while checking the segments. The request stores the value for
merging and quickly checking per io if the request can use iova
optimizations.
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>
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Now that the bio_iov_iter_get_pages is free again, use it instead of
the more complicated now. Also drop the unused export.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Switch the only caller to bio_iov_iter_get_pages, and explain why it does
not have any alignment requirements.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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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>
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We're already iterating every segment, so check these for a valid IO
lengths at the same time. Individual segment lengths will not be checked
on passthrough commands. The read/write command segments must be sized
to the dma alignment.
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>
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Bios are embedded into other structures, and at least spare is unhappy
about embedding structures with variable sized arrays. There's no
real need to the array anyway, we can replace it with a helper pointing
to the memory just behind the bio, and with the previous cleanups there
is very few site doing anything special with it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Just a simpler wrapper around bio_init for callers that want to
initialize a bio with inline bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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It is possible for physically contiguous folios to have discontiguous
struct pages if SPARSEMEM is enabled and SPARSEMEM_VMEMMAP is not.
This is correctly handled by folio_page_idx(), so remove this open-coded
implementation.
Fixes: 640d1930bef4 (block: Add bio_for_each_folio_all())
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20250612144126.2849931-1-willy@infradead.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Pull block updates from Jens Axboe:
- ublk updates:
- Add support for updating the size of a ublk instance
- Zero-copy improvements
- Auto-registering of buffers for zero-copy
- Series simplifying and improving GET_DATA and request lookup
- Series adding quiesce support
- Lots of selftests additions
- Various cleanups
- NVMe updates via Christoph:
- add per-node DMA pools and use them for PRP/SGL allocations
(Caleb Sander Mateos, Keith Busch)
- nvme-fcloop refcounting fixes (Daniel Wagner)
- support delayed removal of the multipath node and optionally
support the multipath node for private namespaces (Nilay Shroff)
- support shared CQs in the PCI endpoint target code (Wilfred
Mallawa)
- support admin-queue only authentication (Hannes Reinecke)
- use the crc32c library instead of the crypto API (Eric Biggers)
- misc cleanups (Christoph Hellwig, Marcelo Moreira, Hannes
Reinecke, Leon Romanovsky, Gustavo A. R. Silva)
- MD updates via Yu:
- Fix that normal IO can be starved by sync IO, found by mkfs on
newly created large raid5, with some clean up patches for bdev
inflight counters
- Clean up brd, getting rid of atomic kmaps and bvec poking
- Add loop driver specifically for zoned IO testing
- Eliminate blk-rq-qos calls with a static key, if not enabled
- Improve hctx locking for when a plug has IO for multiple queues
pending
- Remove block layer bouncing support, which in turn means we can
remove the per-node bounce stat as well
- Improve blk-throttle support
- Improve delay support for blk-throttle
- Improve brd discard support
- Unify IO scheduler switching. This should also fix a bunch of lockdep
warnings we've been seeing, after enabling lockdep support for queue
freezing/unfreezeing
- Add support for block write streams via FDP (flexible data placement)
on NVMe
- Add a bunch of block helpers, facilitating the removal of a bunch of
duplicated boilerplate code
- Remove obsolete BLK_MQ pci and virtio Kconfig options
- Add atomic/untorn write support to blktrace
- Various little cleanups and fixes
* tag 'for-6.16/block-20250523' of git://git.kernel.dk/linux: (186 commits)
selftests: ublk: add test for UBLK_F_QUIESCE
ublk: add feature UBLK_F_QUIESCE
selftests: ublk: add test case for UBLK_U_CMD_UPDATE_SIZE
traceevent/block: Add REQ_ATOMIC flag to block trace events
ublk: run auto buf unregisgering in same io_ring_ctx with registering
io_uring: add helper io_uring_cmd_ctx_handle()
ublk: remove io argument from ublk_auto_buf_reg_fallback()
ublk: handle ublk_set_auto_buf_reg() failure correctly in ublk_fetch()
selftests: ublk: add test for covering UBLK_AUTO_BUF_REG_FALLBACK
selftests: ublk: support UBLK_F_AUTO_BUF_REG
ublk: support UBLK_AUTO_BUF_REG_FALLBACK
ublk: register buffer to local io_uring with provided buf index via UBLK_F_AUTO_BUF_REG
ublk: prepare for supporting to register request buffer automatically
ublk: convert to refcount_t
selftests: ublk: make IO & device removal test more stressful
nvme: rename nvme_mpath_shutdown_disk to nvme_mpath_remove_disk
nvme: introduce multipath_always_on module param
nvme-multipath: introduce delayed removal of the multipath head node
nvme-pci: derive and better document max segments limits
nvme-pci: use struct_size for allocation struct nvme_dev
...
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The REPORT ZONES buffer size is currently limited by the HBA's maximum
segment count to ensure the buffer can be mapped. However, the block
layer further limits the number of iovec entries to 1024 when allocating
a bio.
To avoid allocation of buffers too large to be mapped, further restrict
the maximum buffer size to BIO_MAX_INLINE_VECS.
Replace the UIO_MAXIOV symbolic name with the more contextually
appropriate BIO_MAX_INLINE_VECS.
Fixes: b091ac616846 ("sd_zbc: Fix report zones buffer allocation")
Cc: stable@vger.kernel.org
Signed-off-by: Steve Siwinski <ssiwinski@atto.com>
Link: https://lore.kernel.org/r/20250508200122.243129-1-ssiwinski@atto.com
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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Add a helper to add a vmalloc region to a bio, abstracting away the
vmalloc addresses from the underlying pages and another one wrapping
it for the simple case where all data fits into a single bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250507120451.4000627-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Add a helper to check how many bio_vecs are needed to add a kernel
virtual address range to a bio, accounting for the always contiguous
direct mapping and vmalloc mappings that usually need a bio_vec
per page sized chunk.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250507120451.4000627-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Add a helper to perform synchronous I/O on a kernel direct map range.
Currently this is implemented in various places in usually not very
efficient ways, so provide a generic helper instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250507120451.4000627-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Add a helper to add a directly mapped kernel virtual address to a
bio so that callers don't have to convert to pages or folios.
For now only the _nofail variant is provided as that is what all the
obvious callers want.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250507120451.4000627-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Many of the fields in struct bio_integrity_payload are only needed for
the default integrity buffer in the block layer, and the variable
sized array at the end of the structure makes it very hard to embed
into caller allocated structures.
Reduce struct bio_integrity_payload to the minimal structure needed in
common code and create two separate containing structures for the
automatically generated payload and the caller allocated payload.
The latter is a simple wrapper for struct bio_integrity_payload and
the bvecs, while the former contains the additional fields moved out
of struct bio_integrity_payload.
Always use a dedicated mempool for automatic integrity metadata
instead of depending on bio_set that is submitter controlled and thus
often doesn't have the mempool initialized and stop using mempools for
the submitter buffers as they aren't in the NOIO I/O submission path
where we need to guarantee forward progress.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250225154449.422989-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Lift bio_split_rw_at into blk_rq_append_bio so that it validates the
hardware limits. With this all passthrough callers can simply add
bio_add_page to build the bio and delay checking for exceeding of limits
to this point instead of doing it for each page.
While this looks like adding a new expensive loop over all bio_vecs,
blk_rq_append_bio is already doing that just to counter the number of
segments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20250103073417.459715-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Since commit 43b62ce3ff0a ("block: move bio io prio to a new field"), macro
bio_set_prio() does nothing but set bio->bi_ioprio. All other places just
set bio->bi_ioprio directly, so replace bio_set_prio() remaining
callsites with setting bio->bi_ioprio directly and delete that macro.
Signed-off-by: John Garry <john.g.garry@oracle.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20241202111957.2311683-3-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Since commit 43b62ce3ff0a ("block: move bio io prio to a new field"), macro
bio_prio() does nothing but return the value in bio->bi_ioprio. Most other
places just read bio->bi_ioprio directly, so replace bi_ioprio() callsites
with reading bio->bi_ioprio directly and delete that macro.
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20241202111957.2311683-2-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Make bio_iov_bvec_set() accept a pointer to const iov_iter, which means
that we can drop the undesirable casting to struct iov_iter pointer in
blk_rq_map_user_bvec().
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241202115727.2320401-1-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Make bio_is_zone_append globally available, because file systems need
to use to check for a zone append bio in their end_io handlers to deal
with the block layer emulation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20241104062647.91160-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This is only used by the nvmet zns passthrough code, which can trivially
just use bio_add_pc_page and do the sanity check for the max zone append
limit itself.
All future zoned file systems should follow the btrfs lead and let the
upper layers fill up bios unlimited by hardware constraints and split
them to the limits in the I/O submission handler.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20241030051859.280923-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The current setup with bio_may_exceed_limit and __bio_split_to_limits
is a bit of a mess.
Change it so that __bio_split_to_limits does all the work and is just
a variant of bio_split_to_limits that returns nr_segs. This is done
by inlining it and instead have the various bio_split_* helpers directly
submit the potentially split bios.
To support btrfs, the rw version has a lower level helper split out
that just returns the offset to split. This turns out to nicely clean
up the btrfs flow as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>
Link: https://lore.kernel.org/r/20240826173820.1690925-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Split struct bio_integrity_payload and the related prototypes out of
bio.h into a separate bio-integrity.h header so that it is only pulled
in by the few places that need it.
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: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240702151047.1746127-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The user mapped intergity is copied back and unpinned by
bio_integrity_free which is a low-level routine. Do it via the submitter
rather than doing it in the low-level block layer code, to split the
submitter side from the consumer side of the bio.
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20240610111144.14647-1-anuj20.g@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Factor out a helper from __blkdev_issue_discard that chews off as much as
possible from a discard range and allocates a bio for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240506042027.2289826-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This is basically blk_next_bio just with the bio allocation moved
to the caller to allow for more flexible bio handling in the caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240506042027.2289826-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This is a simple combination of bio_list_merge + bio_list_init
similar to list_splice_init. While it only saves a single
line in a callers, it makes the move all bios from one list to
another and reinitialize the original pattern a lot more obvious
in the callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Sakai <msakai@redhat.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240328084147.2954434-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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If the bio contains no data, bio_first_folio() calls page_folio() on a
NULL pointer and oopses. Move the test that we've reached the end of
the bio from bio_next_folio() to bio_first_folio().
Reported-by: syzbot+8b23309d5788a79d3eea@syzkaller.appspotmail.com
Reported-by: syzbot+004c1e0fced2b4bc3dcc@syzkaller.appspotmail.com
Fixes: 640d1930bef4 ("block: Add bio_for_each_folio_all()")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240116212959.3413014-1-willy@infradead.org
[axboe: add unlikely() to error case]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Passthrough commands that utilize metadata currently need to bounce the
user space buffer through the kernel. Add support for mapping user space
directly so that we can avoid this costly overhead. This is similar to
how the normal bio data payload utilizes user addresses with
bio_map_user_iov().
If the user address can't directly be used for reason, like too many
segments or address unalignement, fallback to a copy of the user vec
while keeping the user address pinned for the IO duration so that it
can safely be copied on completion in any process context.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20231130215309.2923568-2-kbusch@meta.com
[axboe: fold in fix from Kanchan Joshi]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Pull block updates from Jens Axboe:
"Pretty quiet round for this release. This contains:
- Add support for zoned storage to ublk (Andreas, Ming)
- Series improving performance for drivers that mark themselves as
needing a blocking context for issue (Bart)
- Cleanup the flush logic (Chengming)
- sed opal keyring support (Greg)
- Fixes and improvements to the integrity support (Jinyoung)
- Add some exports for bcachefs that we can hopefully delete again in
the future (Kent)
- deadline throttling fix (Zhiguo)
- Series allowing building the kernel without buffer_head support
(Christoph)
- Sanitize the bio page adding flow (Christoph)
- Write back cache fixes (Christoph)
- MD updates via Song:
- Fix perf regression for raid0 large sequential writes (Jan)
- Fix split bio iostat for raid0 (David)
- Various raid1 fixes (Heinz, Xueshi)
- raid6test build fixes (WANG)
- Deprecate bitmap file support (Christoph)
- Fix deadlock with md sync thread (Yu)
- Refactor md io accounting (Yu)
- Various non-urgent fixes (Li, Yu, Jack)
- Various fixes and cleanups (Arnd, Azeem, Chengming, Damien, Li,
Ming, Nitesh, Ruan, Tejun, Thomas, Xu)"
* tag 'for-6.6/block-2023-08-28' of git://git.kernel.dk/linux: (113 commits)
block: use strscpy() to instead of strncpy()
block: sed-opal: keyring support for SED keys
block: sed-opal: Implement IOC_OPAL_REVERT_LSP
block: sed-opal: Implement IOC_OPAL_DISCOVERY
blk-mq: prealloc tags when increase tagset nr_hw_queues
blk-mq: delete redundant tagset map update when fallback
blk-mq: fix tags leak when shrink nr_hw_queues
ublk: zoned: support REQ_OP_ZONE_RESET_ALL
md: raid0: account for split bio in iostat accounting
md/raid0: Fix performance regression for large sequential writes
md/raid0: Factor out helper for mapping and submitting a bio
md raid1: allow writebehind to work on any leg device set WriteMostly
md/raid1: hold the barrier until handle_read_error() finishes
md/raid1: free the r1bio before waiting for blocked rdev
md/raid1: call free_r1bio() before allow_barrier() in raid_end_bio_io()
blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init
drivers/rnbd: restore sysfs interface to rnbd-client
md/raid5-cache: fix null-ptr-deref for r5l_flush_stripe_to_raid()
raid6: test: only check for Altivec if building on powerpc hosts
raid6: test: make sure all intermediate and artifact files are .gitignored
...
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git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- Some swap cleanups from Ma Wupeng ("fix WARN_ON in
add_to_avail_list")
- Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which
reduces the special-case code for handling hugetlb pages in GUP. It
also speeds up GUP handling of transparent hugepages.
- Peng Zhang provides some maple tree speedups ("Optimize the fast path
of mas_store()").
- Sergey Senozhatsky has improved te performance of zsmalloc during
compaction (zsmalloc: small compaction improvements").
- Domenico Cerasuolo has developed additional selftest code for zswap
("selftests: cgroup: add zswap test program").
- xu xin has doe some work on KSM's handling of zero pages. These
changes are mainly to enable the user to better understand the
effectiveness of KSM's treatment of zero pages ("ksm: support
tracking KSM-placed zero-pages").
- Jeff Xu has fixes the behaviour of memfd's
MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl
MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED").
- David Howells has fixed an fscache optimization ("mm, netfs, fscache:
Stop read optimisation when folio removed from pagecache").
- Axel Rasmussen has given userfaultfd the ability to simulate memory
poisoning ("add UFFDIO_POISON to simulate memory poisoning with
UFFD").
- Miaohe Lin has contributed some routine maintenance work on the
memory-failure code ("mm: memory-failure: remove unneeded PageHuge()
check").
- Peng Zhang has contributed some maintenance work on the maple tree
code ("Improve the validation for maple tree and some cleanup").
- Hugh Dickins has optimized the collapsing of shmem or file pages into
THPs ("mm: free retracted page table by RCU").
- Jiaqi Yan has a patch series which permits us to use the healthy
subpages within a hardware poisoned huge page for general purposes
("Improve hugetlbfs read on HWPOISON hugepages").
- Kemeng Shi has done some maintenance work on the pagetable-check code
("Remove unused parameters in page_table_check").
- More folioification work from Matthew Wilcox ("More filesystem folio
conversions for 6.6"), ("Followup folio conversions for zswap"). And
from ZhangPeng ("Convert several functions in page_io.c to use a
folio").
- page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext").
- Baoquan He has converted some architectures to use the
GENERIC_IOREMAP ioremap()/iounmap() code ("mm: ioremap: Convert
architectures to take GENERIC_IOREMAP way").
- Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support
batched/deferred tlb shootdown during page reclamation/migration").
- Better maple tree lockdep checking from Liam Howlett ("More strict
maple tree lockdep"). Liam also developed some efficiency
improvements ("Reduce preallocations for maple tree").
- Cleanup and optimization to the secondary IOMMU TLB invalidation,
from Alistair Popple ("Invalidate secondary IOMMU TLB on permission
upgrade").
- Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes
for arm64").
- Kemeng Shi provides some maintenance work on the compaction code
("Two minor cleanups for compaction").
- Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle
most file-backed faults under the VMA lock").
- Aneesh Kumar contributes code to use the vmemmap optimization for DAX
on ppc64, under some circumstances ("Add support for DAX vmemmap
optimization for ppc64").
- page-ext cleanups from Kemeng Shi ("add page_ext_data to get client
data in page_ext"), ("minor cleanups to page_ext header").
- Some zswap cleanups from Johannes Weiner ("mm: zswap: three
cleanups").
- kmsan cleanups from ZhangPeng ("minor cleanups for kmsan").
- VMA handling cleanups from Kefeng Wang ("mm: convert to
vma_is_initial_heap/stack()").
- DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes:
implement DAMOS tried total bytes file"), ("Extend DAMOS filters for
address ranges and DAMON monitoring targets").
- Compaction work from Kemeng Shi ("Fixes and cleanups to compaction").
- Liam Howlett has improved the maple tree node replacement code
("maple_tree: Change replacement strategy").
- ZhangPeng has a general code cleanup - use the K() macro more widely
("cleanup with helper macro K()").
- Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for
memmap on memory feature on ppc64").
- pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list
in page_alloc"), ("Two minor cleanups for get pageblock
migratetype").
- Vishal Moola introduces a memory descriptor for page table tracking,
"struct ptdesc" ("Split ptdesc from struct page").
- memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups
for vm.memfd_noexec").
- MM include file rationalization from Hugh Dickins ("arch: include
asm/cacheflush.h in asm/hugetlb.h").
- THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text
output").
- kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use
object_cache instead of kmemleak_initialized").
- More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor
and _folio_order").
- A VMA locking scalability improvement from Suren Baghdasaryan
("Per-VMA lock support for swap and userfaults").
- pagetable handling cleanups from Matthew Wilcox ("New page table
range API").
- A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop
using page->private on tail pages for THP_SWAP + cleanups").
- Cleanups and speedups to the hugetlb fault handling from Matthew
Wilcox ("Change calling convention for ->huge_fault").
- Matthew Wilcox has also done some maintenance work on the MM
subsystem documentation ("Improve mm documentation").
* tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (489 commits)
maple_tree: shrink struct maple_tree
maple_tree: clean up mas_wr_append()
secretmem: convert page_is_secretmem() to folio_is_secretmem()
nios2: fix flush_dcache_page() for usage from irq context
hugetlb: add documentation for vma_kernel_pagesize()
mm: add orphaned kernel-doc to the rst files.
mm: fix clean_record_shared_mapping_range kernel-doc
mm: fix get_mctgt_type() kernel-doc
mm: fix kernel-doc warning from tlb_flush_rmaps()
mm: remove enum page_entry_size
mm: allow ->huge_fault() to be called without the mmap_lock held
mm: move PMD_ORDER to pgtable.h
mm: remove checks for pte_index
memcg: remove duplication detection for mem_cgroup_uncharge_swap
mm/huge_memory: work on folio->swap instead of page->private when splitting folio
mm/swap: inline folio_set_swap_entry() and folio_swap_entry()
mm/swap: use dedicated entry for swap in folio
mm/swap: stop using page->private on tail pages for THP_SWAP
selftests/mm: fix WARNING comparing pointer to 0
selftests: cgroup: fix test_kmem_memcg_deletion kernel mem check
...
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Introduce bio_first_folio_all() to return a folio, which makes it easier
to use.
Link: https://lkml.kernel.org/r/20230721034451.16412-4-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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This reverts 6f822e1b5d9dda3d20e87365de138046e3baa03a - this helper is
used by bcachefs.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Link: https://lore.kernel.org/r/20230813182636.2966159-4-kent.overstreet@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Normally these two flags do go together, as the issuer of polled IO
generally cannot wait for resources that will get freed as part of IO
completion. This is because that very task is the one that will complete
the request and free those resources, hence that would introduce a
deadlock.
But it is possible to have someone else issue the polled IO, eg via
io_uring if the request is punted to io-wq. For that case, it's fine to
have the task block on IO submission, as it is not the same task that
will be completing the IO.
It's completely up to the caller to ask for both polled and nowait IO
separately! If we don't allow polled IO where IOCB_NOWAIT isn't set in
the kiocb, then we can run into repeated -EAGAIN submissions and not
make any progress.
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Now that all block direct I/O helpers use page pinning, this flag is
unused.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230614140341.521331-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Now that all callers of bio_add_folio() check the return value, mark it as
__must_check.
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/381360a45ac3684120cfbe1e07685e9c36256e47.1685532726.git.johannes.thumshirn@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Just like for bio_add_pages() add a no-fail variant for bio_add_folio().
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/924dff4077812804398ef84128fb920507fa4be1.1685532726.git.johannes.thumshirn@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
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Now that all users of bio_add_page check for the return value, mark
bio_add_page as __must_check.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/7ae4a902e08fe2e90c012ee07aeb35d4aae28373.1685532726.git.johannes.thumshirn@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Add BIO_PAGE_PINNED to indicate that the pages in a bio are pinned
(FOLL_PIN) and that the pin will need removing.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Jan Kara <jack@suse.cz>
cc: Matthew Wilcox <willy@infradead.org>
cc: Logan Gunthorpe <logang@deltatee.com>
cc: linux-block@vger.kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230522205744.2825689-5-dhowells@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Replace BIO_NO_PAGE_REF with a BIO_PAGE_REFFED flag that has the inverted
meaning is only set when a page reference has been acquired that needs to
be released by bio_release_pages().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Jan Kara <jack@suse.cz>
cc: Matthew Wilcox <willy@infradead.org>
cc: Logan Gunthorpe <logang@deltatee.com>
cc: linux-block@vger.kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230522205744.2825689-4-dhowells@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Fix bio_flagged() so that multiple instances of it, such as:
if (bio_flagged(bio, BIO_PAGE_REFFED) ||
bio_flagged(bio, BIO_PAGE_PINNED))
can be combined by the gcc optimiser into a single test in assembly
(arguably, this is a compiler optimisation issue[1]).
The missed optimisation stems from bio_flagged() comparing the result of
the bitwise-AND to zero. This results in an out-of-line bio_release_page()
being compiled to something like:
<+0>: mov 0x14(%rdi),%eax
<+3>: test $0x1,%al
<+5>: jne 0xffffffff816dac53 <bio_release_pages+11>
<+7>: test $0x2,%al
<+9>: je 0xffffffff816dac5c <bio_release_pages+20>
<+11>: movzbl %sil,%esi
<+15>: jmp 0xffffffff816daba1 <__bio_release_pages>
<+20>: jmp 0xffffffff81d0b800 <__x86_return_thunk>
However, the test is superfluous as the return type is bool. Removing it
results in:
<+0>: testb $0x3,0x14(%rdi)
<+4>: je 0xffffffff816e4af4 <bio_release_pages+15>
<+6>: movzbl %sil,%esi
<+10>: jmp 0xffffffff816dab7c <__bio_release_pages>
<+15>: jmp 0xffffffff81d0b7c0 <__x86_return_thunk>
instead.
Also, the MOVZBL instruction looks unnecessary[2] - I think it's just
're-booling' the mark_dirty parameter.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: linux-block@vger.kernel.org
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108370 [1]
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108371 [2]
Link: https://lore.kernel.org/r/167391056756.2311931.356007731815807265.stgit@warthog.procyon.org.uk/ # v6
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230522205744.2825689-3-dhowells@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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REQ_CGROUP_PUNT is a bit annoying as it is hard to follow and adds
a branch to the bio submission hot path. To fix this, export
blkcg_punt_bio_submit and let btrfs call it directly. Add a new
REQ_FS_PRIVATE flag for btrfs to indicate to it's own low-level
bio submission code that a punt to the cgroup submission helper
is required.
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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bio_split_rw can be used by file systems to split and incoming write
bio into multiple bios fitting the hardware limit for use as ZONE_APPEND
bios. Export it for initial use in btrfs.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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This reverts commit db1c7d77976775483a8ef240b4c705f113e13ea1.
We're reinstating the pktcdvd driver, which needs this API.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
