Add a new blk_rq_dma_map / blk_rq_dma_unmap pair that does away with
the wasteful scatterlist structure. Instead it uses the mapping iterator
to either add segments to the IOVA for IOMMU operations, or just maps
them one by one for the direct mapping. For the IOMMU case instead of
a scatterlist with an entry for each segment, only a single [dma_addr,len]
pair needs to be stored for processing a request, and for the direct
mapping the per-segment allocation shrinks from
[page,offset,len,dma_addr,dma_len] to just [dma_addr,len].
One big difference to the scatterlist API, which could be considered
downside, is that the IOVA collapsing only works when the driver sets
a virt_boundary that matches the IOMMU granule. For NVMe this is done
already so it works perfectly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20250625113531.522027-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To get out of the DMA mapping helpers having to check every segment for
it's P2P status, ensure that bios either contain P2P transfers or non-P2P
transfers, and that a P2P bio only contains ranges from a single device.
This means we do the page zone access in the bio add path where it should
be still page hot, and will only have do the fairly expensive P2P topology
lookup once per bio down in the DMA mapping path, and only for already
marked bios.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20250625113531.522027-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation for fixing device mapper zone write handling, introduce
the inline helper function bio_needs_zone_write_plugging() to test if a
BIO requires handling through zone write plugging using the function
blk_zone_plug_bio(). This function returns true for any write
(op_is_write(bio) == true) operation directed at a zoned block device
using zone write plugging, that is, a block device with a disk that has
a zone write plug hash table.
This helper allows simplifying the check on entry to blk_zone_plug_bio()
and used in to protect calls to it for blk-mq devices and DM devices.
Fixes: f211268ed1 ("dm: Use the block layer zone append emulation")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250625093327.548866-3-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Back in 2015, commit d2be537c3b ("block: bump BLK_DEF_MAX_SECTORS to
2560") increased the default maximum size of a block device I/O to 2560
sectors (1280 KiB) to "accommodate a 10-data-disk stripe write with
chunk size 128k". This choice is rather arbitrary and since then,
improvements to the block layer have software RAID drivers correctly
advertize their stripe width through chunk_sectors and abuses of
BLK_DEF_MAX_SECTORS_CAP by drivers (to set the HW limit rather than the
default user controlled maximum I/O size) have been fixed.
Since many block devices can benefit from a larger value of
BLK_DEF_MAX_SECTORS_CAP, and in particular HDDs, increase this value to
be 4MiB, or 8192 sectors.
And given that BLK_DEF_MAX_SECTORS_CAP is only used in the block layer
and should not be used by drivers directly, move this macro definition
to the block layer internal header file block/blk.h.
Suggested-by: Martin K . Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20250618060045.37593-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.16-20250626' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- Fixes for ublk:
- fix C++ narrowing warnings in the uapi header
- update/improve UBLK_F_SUPPORT_ZERO_COPY comment in uapi header
- fix for the ublk ->queue_rqs() implementation, limiting a batch
to just the specific task AND ring
- ublk_get_data() error handling fix
- sanity check more arguments in ublk_ctrl_add_dev()
- selftest addition
- NVMe pull request via Christoph:
- reset delayed remove_work after reconnect
- fix atomic write size validation
- Fix for a warning introduced in bdev_count_inflight_rw() in this
merge window
* tag 'block-6.16-20250626' of git://git.kernel.dk/linux:
block: fix false warning in bdev_count_inflight_rw()
ublk: sanity check add_dev input for underflow
nvme: fix atomic write size validation
nvme: refactor the atomic write unit detection
nvme: reset delayed remove_work after reconnect
ublk: setup ublk_io correctly in case of ublk_get_data() failure
ublk: update UBLK_F_SUPPORT_ZERO_COPY comment in UAPI header
ublk: fix narrowing warnings in UAPI header
selftests: ublk: don't take same backing file for more than one ublk devices
ublk: build batch from IOs in same io_ring_ctx and io task
block_write_end() looks like it can be used as a ->write_end()
implementation. However, it can't as it does not unlock nor put
the folio. Since it does not use the 'file', 'mapping' nor 'fsdata'
arguments, remove them.
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/20250624132130.1590285-1-willy@infradead.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add support for FALLOC_FL_WRITE_ZEROES, if the block device enables the
unmap write zeroes operation, it will issue a write zeroes command.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/20250619111806.3546162-9-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Only the flags passed to blkdev_issue_zeroout() differ among the two
zeroing branches in blkdev_fallocate(). Therefore, do cleanup by
factoring them out.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/20250619111806.3546162-8-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Currently, disks primarily implement the write zeroes command (aka
REQ_OP_WRITE_ZEROES) through two mechanisms: the first involves
physically writing zeros to the disk media (e.g., HDDs), while the
second performs an unmap operation on the logical blocks, effectively
putting them into a deallocated state (e.g., SSDs). The first method is
generally slow, while the second method is typically very fast.
For example, on certain NVMe SSDs that support NVME_NS_DEAC, submitting
REQ_OP_WRITE_ZEROES requests with the NVME_WZ_DEAC bit can accelerate
the write zeros operation by placing disk blocks into a deallocated
state, which opportunistically avoids writing zeroes to media while
still guaranteeing that subsequent reads from the specified block range
will return zeroed data. This is a best-effort optimization, not a
mandatory requirement, some devices may partially fall back to writing
physical zeroes due to factors such as misalignment or being asked to
clear a block range smaller than the device's internal allocation unit.
Therefore, the speed of this operation is not guaranteed.
It is difficult to determine whether the storage device supports unmap
write zeroes operation. We cannot determine this by only querying
bdev_limits(bdev)->max_write_zeroes_sectors. Therefore, first, add a new
hardware queue limit parameters, max_hw_wzeroes_unmap_sectors, to
indicate whether a device supports this unmap write zeroes operation.
Then, add two new counterpart software queue limits,
max_wzeroes_unmap_sectors and max_user_wzeroes_unmap_sectors, which
allow users to disable this operation if the speed is very slow on some
sepcial devices.
Finally, for the stacked devices cases, initialize these two parameters
to UINT_MAX. This operation should be enabled by both the stacking
driver and all underlying devices.
Thanks to Martin K. Petersen for optimizing the documentation of the
write_zeroes_unmap sysfs interface.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/20250619111806.3546162-2-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Update nearly all generic_file_mmap() and generic_file_readonly_mmap()
callers to use generic_file_mmap_prepare() and
generic_file_readonly_mmap_prepare() respectively.
We update blkdev, 9p, afs, erofs, ext2, nfs, ntfs3, smb, ubifs and vboxsf
file systems this way.
Remaining users we cannot yet update are ecryptfs, fuse and cramfs. The
former two are nested file systems that must support any underlying file
ssytem, and cramfs inserts a mixed mapping which currently requires a VMA.
Once all file systems have been converted to mmap_prepare(), we can then
update nested file systems.
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Link: https://lore.kernel.org/08db85970d89b17a995d2cffae96fb4cc462377f.1750099179.git.lorenzo.stoakes@oracle.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Merge tag 'block-6.16-20250614' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- Fix for a deadlock on queue freeze with zoned writes
- Fix for zoned append emulation
- Two bio folio fixes, for sparsemem and for very large folios
- Fix for a performance regression introduced in 6.13 when plug
insertion was changed
- Fix for NVMe passthrough handling for polled IO
- Document the ublk auto registration feature
- loop lockdep warning fix
* tag 'block-6.16-20250614' of git://git.kernel.dk/linux:
nvme: always punt polled uring_cmd end_io work to task_work
Documentation: ublk: Separate UBLK_F_AUTO_BUF_REG fallback behavior sublists
block: Fix bvec_set_folio() for very large folios
bio: Fix bio_first_folio() for SPARSEMEM without VMEMMAP
block: use plug request list tail for one-shot backmerge attempt
block: don't use submit_bio_noacct_nocheck in blk_zone_wplug_bio_work
block: Clear BIO_EMULATES_ZONE_APPEND flag on BIO completion
ublk: document auto buffer registration(UBLK_F_AUTO_BUF_REG)
loop: move lo_set_size() out of queue freeze
Previously, the block layer stored the requests in the plug list in
LIFO order. For this reason, blk_attempt_plug_merge() would check
just the head entry for a back merge attempt, and abort after that
unless requests for multiple queues existed in the plug list. If more
than one request is present in the plug list, this makes the one-shot
back merging less useful than before, as it'll always fail to find a
quick merge candidate.
Use the tail entry for the one-shot merge attempt, which is the last
added request in the list. If that fails, abort immediately unless
there are multiple queues available. If multiple queues are available,
then scan the list. Ideally the latter scan would be a backwards scan
of the list, but as it currently stands, the plug list is singly linked
and hence this isn't easily feasible.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-block/20250611121626.7252-1-abuehaze@amazon.com/
Reported-by: Hazem Mohamed Abuelfotoh <abuehaze@amazon.com>
Fixes: e70c301fae ("block: don't reorder requests in blk_add_rq_to_plug")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Bios queued up in the zone write plug have already gone through all all
preparation in the submit_bio path, including the freeze protection.
Submitting them through submit_bio_noacct_nocheck duplicates the work
and can can cause deadlocks when freezing a queue with pending bio
write plugs.
Go straight to ->submit_bio or blk_mq_submit_bio to bypass the
superfluous extra freeze protection and checks.
Fixes: 9b1ce7f0c6 ("block: Implement zone append emulation")
Reported-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20250611044416.2351850-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When blk_zone_write_plug_bio_endio() is called for a regular write BIO
used to emulate a zone append operation, that is, a BIO flagged with
BIO_EMULATES_ZONE_APPEND, the BIO operation code is restored to the
original REQ_OP_ZONE_APPEND but the BIO_EMULATES_ZONE_APPEND flag is not
cleared. Clear it to fully return the BIO to its orginal definition.
Fixes: 9b1ce7f0c6 ("block: Implement zone append emulation")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250611005915.89843-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move this API to the canonical timer_*() namespace.
[ tglx: Redone against pre rc1 ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
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Merge tag 'block-6.16-20250606' of git://git.kernel.dk/linux
Pull more block updates from Jens Axboe:
- NVMe pull request via Christoph:
- TCP error handling fix (Shin'ichiro Kawasaki)
- TCP I/O stall handling fixes (Hannes Reinecke)
- fix command limits status code (Keith Busch)
- support vectored buffers also for passthrough (Pavel Begunkov)
- spelling fixes (Yi Zhang)
- MD pull request via Yu:
- fix REQ_RAHEAD and REQ_NOWAIT IO err handling for raid1/10
- fix max_write_behind setting for dm-raid
- some minor cleanups
- Integrity data direction fix and cleanup
- bcache NULL pointer fix
- Fix for loop missing write start/end handling
- Decouple hardware queues and IO threads in ublk
- Slew of ublk selftests additions and updates
* tag 'block-6.16-20250606' of git://git.kernel.dk/linux: (29 commits)
nvme: spelling fixes
nvme-tcp: fix I/O stalls on congested sockets
nvme-tcp: sanitize request list handling
nvme-tcp: remove tag set when second admin queue config fails
nvme: enable vectored registered bufs for passthrough cmds
nvme: fix implicit bool to flags conversion
nvme: fix command limits status code
selftests: ublk: kublk: improve behavior on init failure
block: flip iter directions in blk_rq_integrity_map_user()
block: drop direction param from bio_integrity_copy_user()
selftests: ublk: cover PER_IO_DAEMON in more stress tests
Documentation: ublk: document UBLK_F_PER_IO_DAEMON
selftests: ublk: add stress test for per io daemons
selftests: ublk: add functional test for per io daemons
selftests: ublk: kublk: decouple ublk_queues from ublk server threads
selftests: ublk: kublk: move per-thread data out of ublk_queue
selftests: ublk: kublk: lift queue initialization out of thread
selftests: ublk: kublk: tie sqe allocation to io instead of queue
selftests: ublk: kublk: plumb q_id in io_uring user_data
ublk: have a per-io daemon instead of a per-queue daemon
...
blk_rq_integrity_map_user() creates the ubuf iter with ITER_DEST for
write-direction operations and ITER_SOURCE for read-direction ones.
This is backwards; writes use the user buffer as a source for metadata
and reads use it as a destination. Switch to the rq_data_dir() helper,
which maps writes to ITER_SOURCE (WRITE) and reads to ITER_DEST(READ).
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: fe8f4ca710 ("block: modify bio_integrity_map_user to accept iov_iter as argument")
Link: https://lore.kernel.org/r/20250603184752.1185676-1-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- dm-delay: don't busy-wait in kthread
- dm: use use generic disable_* functions instead of open coding them
- dm: lock queue limits when reading them
- dm-verity: use softirq context only when !need_resched()
- dm-bufio: remove maximum age based eviction
- dm: remove unneeded kvfree from alloc_targets
- dm-flakey: various fixes
- dm-mpath: interface for explicit probing of active paths
- dm: fix BLK_FEAT_ATOMIC_WRITES
- dm: pass through operations on wrapped inline crypto keys
- dm vdo indexer: don't read request structure after enqueuing
- dm-zone: Use bdev_*() helper functions where applicable
- dm-mpath: replace spin_lock_irqsave with spin_lock_irq
- dm-mirror: fix a tiny race condition
- dm-verity: fix a memory leak if some arguments are specified multiple times
- dm-stripe: small code cleanup
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Merge tag 'for-6.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mikulas Patocka:
- better error handling when reloading a table
- use use generic disable_* functions instead of open coding them
- lock queue limits when reading them
- remove unneeded kvfree from alloc_targets
- fix BLK_FEAT_ATOMIC_WRITES
- pass through operations on wrapped inline crypto keys
- dm-verity:
- use softirq context only when !need_resched()
- fix a memory leak if some arguments are specified multiple times
- dm-mpath:
- interface for explicit probing of active paths
- replace spin_lock_irqsave with spin_lock_irq
- dm-delay: don't busy-wait in kthread
- dm-bufio: remove maximum age based eviction
- dm-flakey: various fixes
- vdo indexer: don't read request structure after enqueuing
- dm-zone: Use bdev_*() helper functions where applicable
- dm-mirror: fix a tiny race condition
- dm-stripe: small code cleanup
* tag 'for-6.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (29 commits)
dm-stripe: small code cleanup
dm-verity: fix a memory leak if some arguments are specified multiple times
dm-mirror: fix a tiny race condition
dm-table: check BLK_FEAT_ATOMIC_WRITES inside limits_lock
dm mpath: replace spin_lock_irqsave with spin_lock_irq
dm-mpath: Don't grab work_mutex while probing paths
dm-zone: Use bdev_*() helper functions where applicable
dm vdo indexer: don't read request structure after enqueuing
dm: pass through operations on wrapped inline crypto keys
blk-crypto: export wrapped key functions
dm-table: Set BLK_FEAT_ATOMIC_WRITES for target queue limits
dm mpath: Interface for explicit probing of active paths
dm: Allow .prepare_ioctl to handle ioctls directly
dm-flakey: make corrupting read bios work
dm-flakey: remove useless ERROR_READS check in flakey_end_io
dm-flakey: error all IOs when num_features is absent
dm-flakey: Clean up parsing messages
dm: remove unneeded kvfree from alloc_targets
dm-bufio: remove maximum age based eviction
dm-verity: use softirq context only when !need_resched()
...
direction is determined from bio, which is already passed in. Compute
op_is_write(bio_op(bio)) directly instead of converting it to an iter
direction and back to a bool.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Link: https://lore.kernel.org/r/20250603183133.1178062-1-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- cgroup rstat shared the tracking tree across all controlers with the
rationale being that a cgroup which is using one resource is likely to be
using other resources at the same time (ie. if something is allocating
memory, it's probably consuming CPU cycles). However, this turned out to
not scale very well especially with memcg using rstat for internal
operations which made memcg stat read and flush patterns substantially
different from other controllers. JP Kobryn split the rstat tree per
controller.
- cgroup BPF support was hooking into cgroup init/exit paths directly.
Convert them to use a notifier chain instead so that other usages can be
added easily. The two of the patches which implement this are mislabeled
as belonging to sched_ext instead of cgroup. Sorry.
- Relatively minor cpuset updates.
- Documentation updates.
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Merge tag 'cgroup-for-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
- cgroup rstat shared the tracking tree across all controllers with the
rationale being that a cgroup which is using one resource is likely
to be using other resources at the same time (ie. if something is
allocating memory, it's probably consuming CPU cycles).
However, this turned out to not scale very well especially with memcg
using rstat for internal operations which made memcg stat read and
flush patterns substantially different from other controllers. JP
Kobryn split the rstat tree per controller.
- cgroup BPF support was hooking into cgroup init/exit paths directly.
Convert them to use a notifier chain instead so that other usages can
be added easily. The two of the patches which implement this are
mislabeled as belonging to sched_ext instead of cgroup. Sorry.
- Relatively minor cpuset updates
- Documentation updates
* tag 'cgroup-for-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (23 commits)
sched_ext: Convert cgroup BPF support to use cgroup_lifetime_notifier
sched_ext: Introduce cgroup_lifetime_notifier
cgroup: Minor reorganization of cgroup_create()
cgroup, docs: cpu controller's interaction with various scheduling policies
cgroup, docs: convert space indentation to tab indentation
cgroup: avoid per-cpu allocation of size zero rstat cpu locks
cgroup, docs: be specific about bandwidth control of rt processes
cgroup: document the rstat per-cpu initialization
cgroup: helper for checking rstat participation of css
cgroup: use subsystem-specific rstat locks to avoid contention
cgroup: use separate rstat trees for each subsystem
cgroup: compare css to cgroup::self in helper for distingushing css
cgroup: warn on rstat usage by early init subsystems
cgroup/cpuset: drop useless cpumask_empty() in compute_effective_exclusive_cpumask()
cgroup/rstat: Improve cgroup_rstat_push_children() documentation
cgroup: fix goto ordering in cgroup_init()
cgroup: fix pointer check in css_rstat_init()
cgroup/cpuset: Add warnings to catch inconsistency in exclusive CPUs
cgroup/cpuset: Fix obsolete comment in cpuset_css_offline()
cgroup/cpuset: Always use cpu_active_mask
...
Signed-off-by: Carlos Maiolino <cem@kernel.org>
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Merge tag 'xfs-merge-6.16' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Carlos Maiolino:
- Atomic writes for XFS
- Remove experimental warnings for pNFS, scrub and parent pointers
* tag 'xfs-merge-6.16' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (26 commits)
xfs: add inode to zone caching for data placement
xfs: free the item in xfs_mru_cache_insert on failure
xfs: remove the EXPERIMENTAL warning for pNFS
xfs: remove some EXPERIMENTAL warnings
xfs: Remove deprecated xfs_bufd sysctl parameters
xfs: stop using set_blocksize
xfs: allow sysadmins to specify a maximum atomic write limit at mount time
xfs: update atomic write limits
xfs: add xfs_calc_atomic_write_unit_max()
xfs: add xfs_file_dio_write_atomic()
xfs: commit CoW-based atomic writes atomically
xfs: add large atomic writes checks in xfs_direct_write_iomap_begin()
xfs: add xfs_atomic_write_cow_iomap_begin()
xfs: refine atomic write size check in xfs_file_write_iter()
xfs: refactor xfs_reflink_end_cow_extent()
xfs: allow block allocator to take an alignment hint
xfs: ignore HW which cannot atomic write a single block
xfs: add helpers to compute transaction reservation for finishing intent items
xfs: add helpers to compute log item overhead
xfs: separate out setting buftarg atomic writes limits
...
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Merge tag 'for-6.16/block-20250523' of git://git.kernel.dk/linux
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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Merge tag 'vfs-6.16-rc1.writepage' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull final writepage conversion from Christian Brauner:
"This converts vboxfs from ->writepage() to ->writepages().
This was the last user of the ->writepage() method. So remove
->writepage() completely and all references to it"
* tag 'vfs-6.16-rc1.writepage' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fs: Remove aops->writepage
mm: Remove swap_writepage() and shmem_writepage()
ttm: Call shmem_writeout() from ttm_backup_backup_page()
i915: Use writeback_iter()
shmem: Add shmem_writeout()
writeback: Remove writeback_use_writepage()
migrate: Remove call to ->writepage
vboxsf: Convert to writepages
9p: Add a migrate_folio method
It is possible to eliminate contention between subsystems when
updating/flushing stats by using subsystem-specific locks. Let the existing
rstat locks be dedicated to the cgroup base stats and rename them to
reflect that. Add similar locks to the cgroup_subsys struct for use with
individual subsystems.
Lock initialization is done in the new function ss_rstat_init(ss) which
replaces cgroup_rstat_boot(void). If NULL is passed to this function, the
global base stat locks will be initialized. Otherwise, the subsystem locks
will be initialized.
Change the existing lock helper functions to accept a reference to a css.
Then within these functions, conditionally select the appropriate locks
based on the subsystem affiliation of the given css. Add helper functions
for this selection routine to avoid repeated code.
Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fix to zone block devices to make the maximum segment count match what
the block layer is capable of.
Signed-off-by: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fix from James Bottomley:
"Fix to zone block devices to make the maximum segment count match what
the block layer is capable of"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: sd_zbc: block: Respect bio vector limits for REPORT ZONES buffer
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Merge tag 'block-6.15-20250515' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- NVMe pull request via Christoph:
- fixes for atomic writes (Alan Adamson)
- fixes for polled CQs in nvmet-epf (Damien Le Moal)
- fix for polled CQs in nvme-pci (Keith Busch)
- fix compile on odd configs that need to be forced to inline
(Kees Cook)
- one more quirk (Ilya Guterman)
- Fix for missing allocation of an integrity buffer for some cases
- Fix for a regression with ublk command cancelation
* tag 'block-6.15-20250515' of git://git.kernel.dk/linux:
ublk: fix dead loop when canceling io command
nvme-pci: add NVME_QUIRK_NO_DEEPEST_PS quirk for SOLIDIGM P44 Pro
nvme: all namespaces in a subsystem must adhere to a common atomic write size
nvme: multipath: enable BLK_FEAT_ATOMIC_WRITES for multipathing
nvmet: pci-epf: remove NVMET_PCI_EPF_Q_IS_SQ
nvmet: pci-epf: improve debug message
nvmet: pci-epf: cleanup nvmet_pci_epf_raise_irq()
nvmet: pci-epf: do not fall back to using INTX if not supported
nvmet: pci-epf: clear completion queue IRQ flag on delete
nvme-pci: acquire cq_poll_lock in nvme_poll_irqdisable
nvme-pci: make nvme_pci_npages_prp() __always_inline
block: always allocate integrity buffer when required
blk-mq-dma.c was split from blk-merge.c which has no copyright notice,
but except for some boilerplate code and comments left from the old
version this is all my code, so add my copyright.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250513071433.836797-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While working on the new DMA API I kept getting annoyed how it was placed
right in the middle of the bio splitting code in blk-merge.c.
Split it out into a separate file.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250513071433.836797-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When nr_hw_queues is updated, the elevator needs to be switched to
ensure that we exit elevator and reattach it to ensure that hctx->
sched_tags is correctly allocated for the new hardware queues.
However, elv_update_nr_hw_queues() currently only switches the
elevator if the queue is not registered. This is incorrect, as it
prevents reattaching the elevator after updating nr_hw_queues, which
in turn inhibits allocation of sched_tags.
Fix this by allowing the elevator switch if the queue is registered,
ensuring proper reattachment and resource allocation.
Fixes: 596dce110b ("block: simplify elevator reattachment for updating nr_hw_queues")
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250515134511.548270-1-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If blk-throttle is enabled but blktrace is not, then the compiler will
notice that the following two variables are unused:
../block/blk-throttle.c: In function 'throtl_pending_timer_fn':
../block/blk-throttle.c:1153:30: warning: unused variable 'bio_cnt_w' [-Wunused-variable]
1153 | unsigned int bio_cnt_w = sq_queued(sq, WRITE);
| ^~~~~~~~~
../block/blk-throttle.c:1152:30: warning: unused variable 'bio_cnt_r' [-Wunused-variable]
1152 | unsigned int bio_cnt_r = sq_queued(sq, READ);
| ^~~~~~~~~
Silence that my annotating them with __maybe_unused.
Fixes: 28ad83b774 ("blk-throttle: Split the service queue")
Link: https://lore.kernel.org/all/20250515130830.9671-1-aishwarya.tcv@arm.com/
Reported-by: Aishwarya <aishwarya.tcv@arm.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 9bc1e897a8 ("blk-mq: remove unused queue mapping helpers") makes
the two config options, BLK_MQ_PCI and BLK_MQ_VIRTIO, have no remaining
effect.
Remove the two obsolete config options.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20250514065513.463941-1-lukas.bulwahn@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bvec_try_merge_page currently returns if the added page fragment is
within the same page as the last page in the last current bio_vec.
This information is used by __bio_iov_iter_get_pages so that we always
have a single folio pin per page even when the page is split over
multiple __bio_iov_iter_get_pages calls.
Threading this through the entire lowlevel add page to bio logic is
annoying and inefficient and leads to less code sharing than otherwise
possible. Instead add code to __bio_iov_iter_get_pages that checks if
the bio_vecs did not change and thus a merge into the last segment must
have happened, and if there is an offset into the page for the currently
added fragment, because if yes we must have already had a previous
fragment of the same page in the last bio_vec. While this is still a bit
ugly, it keeps the logic in the one place that needs it and allows for
more code sharing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250512042354.514329-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[BUG]
There has an issue of io delayed dispatch caused by io splitting. Consider
the following scenario:
1) If we set a BPS limit of 1MB/s and restrict the maximum IO size per
dispatch to 4KB, submitting -two- 1MB IO requests results in completion
times of 1s and 2s, which is expected.
2) However, if we additionally set an IOPS limit of 1,000,000/s with the
same BPS limit of 1MB/s, submitting -two- 1MB IO requests again results in
both completing in 2s, even though the IOPS constraint is being met.
[CAUSE]
This issue arises because BPS and IOPS currently share the same queue in
the blkthrotl mechanism:
1) This issue does not occur when only BPS is limited because the split IOs
return false in blk_should_throtl() and do not go through to throtl again.
2) For split IOs, even if they have been tagged with BIO_BPS_THROTTLED,
they still get queued alternately in the same list due to continuous
splitting and reordering. As a result, the two IO requests are both
completed at the 2-second mark, causing an unintended delay.
3) It is not difficult to imagine that in this scenario, if N 1MB IOs are
issued at once, all IOs will eventually complete together in N seconds.
[FIX]
With the queue separation introduced in the previous patches, we now have
separate BPS and IOPS queues. For IOs that have already passed the BPS
limitation, they do not need to re-enter the BPS queue and can directly
placed to the IOPS queue.
Since we have split the queues, when the IOPS queue is previously empty
and a new bio is added to the first qnode->bios_iops list in the
service_queue, we also need to update the disptime. This patch introduces
"THROTL_TG_IOPS_WAS_EMPTY" flag to mark it.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://lore.kernel.org/r/20250506020935.655574-8-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch splits throtl_service_queue->nr_queued into "nr_queued_bps" and
"nr_queued_iops", allowing separate accounting of BPS and IOPS queued bios.
This prepares for future changes that need to check whether the BPS or IOPS
queues are empty.
To facilitate updating the number of IOs in the BPS and IOPS queues, the
addition logic will be moved from throtl_add_bio_tg() to
throtl_qnode_add_bio(), and similarly, the removal logic will be moved from
tg_dispatch_one_bio() to throtl_pop_queued().
And introduce sq_queued() to calculate the total sum of sq->nr_queued.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://lore.kernel.org/r/20250506020935.655574-7-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch splits the single queue into separate bps and iops queues. Now,
an IO request must first pass through the bps queue, then the iops queue,
and finally be dispatched. Due to the queue splitting, we need to modify
the throtl add/peek/pop function.
Additionally, the patch modifies the logic related to tg_dispatch_time().
If bio needs to wait for bps, function directly returns the bps wait time;
otherwise, it charges bps and returns the iops wait time so that bio can be
directly placed into the iops queue afterward. Note that this may lead to
more frequent updates to disptime, but the overhead is negligible for the
slow path.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://lore.kernel.org/r/20250506020935.655574-6-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Subsequent patches will split the single queue into separate bps and iops
queues. To prevent IO that has already passed through the bps queue at a
single tg level from being counted toward bps wait time again, we introduce
"BIO_TG_BPS_THROTTLED" flag. Since throttle and QoS operate at different
levels, we reuse the value as "BIO_QOS_THROTTLED".
We set this flag when charge bps and clear it when charge iops, as the bio
will move to the upper-level tg or be dispatched.
This patch does not involve functional changes.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://lore.kernel.org/r/20250506020935.655574-5-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Split throtl_charge_bio() to facilitate subsequent patches that will
separately charge bps and iops after queue separation.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://lore.kernel.org/r/20250506020935.655574-4-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
tg_dispatch_time() contained both bps and iops throttling logic. We now
split its internal logic into tg_dispatch_bps/iops_time() to improve code
consistency for future separation of the bps and iops queues.
Besides, merge time_before() from caller into throtl_extend_slice() to make
code cleaner.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://lore.kernel.org/r/20250506020935.655574-3-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
tg_may_dispatch() can directly indicate whether bio can be dispatched by
returning the time to wait, without the need for the redundant "wait"
parameter. Remove it and modify the function's return type accordingly.
Since we have determined by the return time whether bio can be dispatched,
rename tg_may_dispatch() to tg_dispatch_time().
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Zizhi Wo <wozizhi@huaweicloud.com>
Link: https://lore.kernel.org/r/20250506020935.655574-2-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull MD changes from Yu Kuai:
- 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.
* tag 'md-6.16-20250513' of https://git.kernel.org/pub/scm/linux/kernel/git/mdraid/linux:
md: clean up accounting for issued sync IO
md: fix is_mddev_idle()
md: add a new api sync_io_depth
md: record dm-raid gendisk in mddev
block: export API to get the number of bdev inflight IO
block: clean up blk_mq_in_flight_rw()
block: WARN if bdev inflight counter is negative
block: reuse part_in_flight_rw for part_in_flight
blk-mq: remove blk_mq_in_flight()
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: b091ac6168 ("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>
In __blk_mq_update_nr_hw_queues(), the current sequence involves:
1. unregistering sysfs/debugfs attributes
2. freeze the queue
3. reallocating the tag set
4. updating the queue map
5. reallocating hardware contexts
6. updating the elevator (which unfreeze the queue again)
7. re-register sysfs/debugfs attributes
If tag set reallocation fails at step 3, the function skips steps 4–6
and proceeds directly to step 7, re-registering the sysfs/debugfs
attributes without unfreezing the queue first. This is incorrect and
can lead to a system hang or lockdep splat, as the queue remains frozen
and is never properly unfrozen.
This patch addresses the issue by explicitly unfreezing the queue before
re-registering the sysfs/debugfs attributes in the event of a tag set
reallocation failure.
Fixes: 9dc7a882ce ("block: move hctx debugfs/sysfs registering out of freezing queue")
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250512092952.135887-1-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Many nvme metadata formats can not strip or generate the metadata on the
controller side. For these formats, a host provided integrity buffer is
mandatory even if it isn't checked.
The block integrity read_verify and write_generate attributes prevent
allocating the metadata buffer, but we need it when the format requires
it, otherwise reads and writes will be rejected by the driver with IO
errors.
Assume the integrity buffer can be offloaded to the controller if the
metadata size is the same as the protection information size. Otherwise
provide an unchecked host buffer when the read verify or write
generation attributes are disabled. This fixes the following nvme
warning:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 371 at drivers/nvme/host/core.c:1036 nvme_setup_rw+0x122/0x210
...
RIP: 0010:nvme_setup_rw+0x122/0x210
...
Call Trace:
<TASK>
nvme_setup_cmd+0x1b4/0x280
nvme_queue_rqs+0xc4/0x1f0 [nvme]
blk_mq_dispatch_queue_requests+0x24a/0x430
blk_mq_flush_plug_list+0x50/0x140
__blk_flush_plug+0xc1/0x100
__submit_bio+0x1c1/0x360
? submit_bio_noacct_nocheck+0x2d6/0x3c0
submit_bio_noacct_nocheck+0x2d6/0x3c0
? submit_bio_noacct+0x47/0x4c0
submit_bio_wait+0x48/0xa0
__blkdev_direct_IO_simple+0xee/0x210
? current_time+0x1d/0x100
? current_time+0x1d/0x100
? __bio_clone+0xb0/0xb0
blkdev_read_iter+0xbb/0x140
vfs_read+0x239/0x310
ksys_read+0x58/0xc0
do_syscall_64+0x6c/0x180
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250509153802.3482493-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- rename part_in_{flight, flight_rw} to bdev_count_{inflight, inflight_rw}
- export bdev_count_inflight, to fix a problem in mdraid that foreground
IO can be starved by background sync IO in later patches
Link: https://lore.kernel.org/linux-raid/20250506124903.2540268-6-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Which means there is a bug for related bio-based disk driver, or blk-mq
for rq-based disk, it's better not to hide the bug.
Link: https://lore.kernel.org/linux-raid/20250506124903.2540268-3-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
After commit 7be835694d ("block: fix that util can be greater than
100%"), it's not used and can be removed.
Link: https://lore.kernel.org/linux-raid/20250506124903.2540268-1-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
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Merge tag 'block-6.15-20250509' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- Fix for a regression in this series for loop and read/write iterator
handling
- zone append block update tweak
- remove a broken IO priority test
- NVMe pull request via Christoph:
- unblock ctrl state transition for firmware update (Daniel
Wagner)
* tag 'block-6.15-20250509' of git://git.kernel.dk/linux:
block: remove test of incorrect io priority level
nvme: unblock ctrl state transition for firmware update
block: only update request sector if needed
loop: Add sanity check for read/write_iter
Ever since commit eca2040972b4("scsi: block: ioprio: Clean up interface
definition"), the macro IOPRIO_PRIO_LEVEL() will mask the level value to
something between 0 and 7 so necessarily, level will always be lower than
IOPRIO_NR_LEVELS(8).
Remove this obsolete check.
Reported-by: Kexin Wei <ys.weikexin@h3c.com>
Cc: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Aaron Lu <ziqianlu@bytedance.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20250508083018.GA769554@bytedance
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When blk_unregister_queue() is called from add_disk() failure path,
there is race in registering/unregistering elevator queue kobject
from the two code paths, because commit 559dc11143 ("block: move
elv_register[unregister]_queue out of elevator_lock") moves elevator
queue register/unregister out of elevator lock.
Fix the race by removing elevator after deleting disk->queue_kobj,
because kobject_del(&disk->queue_kobj) drains in-progress sysfs
show()/store() of all attributes.
Fixes: 559dc11143 ("block: move elv_register[unregister]_queue out of elevator_lock")
Reported-by: Nilay Shroff <nilay@linux.ibm.com>
Suggested-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250508085807.3175112-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_mq_freeze_queue() can't be called on quiesced queue, otherwise it may
never return if there is any queued requests.
Fix it by removing quiesce queue around elevator_set_none() because
elevator_switch() does quiesce queue in case that we need to switch
to none really.
Fixes: 1e44bedbc9 ("block: unifying elevator change")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250508085807.3175112-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
XFS will be able to support large atomic writes (atomic write > 1x block)
in future. This will be achieved by using different operating methods,
depending on the size of the write.
Specifically a new method of operation based in FS atomic extent remapping
will be supported in addition to the current HW offload-based method.
The FS method will generally be appreciably slower performing than the
HW-offload method. However the FS method will be typically able to
contribute to achieving a larger atomic write unit max limit.
XFS will support a hybrid mode, where HW offload method will be used when
possible, i.e. HW offload is used when the length of the write is
supported, and for other times FS-based atomic writes will be used.
As such, there is an atomic write length at which the user may experience
appreciably slower performance.
Advertise this limit in a new statx field, stx_atomic_write_unit_max_opt.
When zero, it means that there is no such performance boundary.
Masks STATX{_ATTR}_WRITE_ATOMIC can be used to get this new field. This is
ok for older kernels which don't support this new field, as they would
report 0 in this field (from zeroing in cp_statx()) already. Furthermore
those older kernels don't support large atomic writes - apart from block
fops, but there would be consistent performance there for atomic writes
in range [unit min, unit max].
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Rewrite bio_map_kern using the new bio_add_* helpers and drop the
kerneldoc comment that is superfluous for an internal helper.
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/20250507120451.4000627-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
That way the bio can be allocated with the right operation already
set and there is no need to pass the separated 'reading' argument.
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/20250507120451.4000627-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove the q argument from blk_rq_map_kern and the internal helpers
called by it as the queue can trivially be derived from the request.
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/20250507120451.4000627-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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>
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>
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>
Export blk_crypto_derive_sw_secret(), blk_crypto_import_key(),
blk_crypto_generate_key(), and blk_crypto_prepare_key() so that they can
be used by device-mapper when passing through wrapped key support.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Use the per-kiocb write stream if provided, or map temperature hints to
write streams (which is a bit questionable, but this shows how it is
done).
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[kbusch: removed statx reporting]
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-6-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Export the granularity that write streams should be discarded with,
as it is essential for making good use of them.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-5-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Drivers with hardware that support write streams need a way to export how
many are available so applications can generically query this.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
[hch: renamed hints to streams, removed stacking]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-4-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add the ability to pass a write stream for placement control in the bio.
The new field fits in an existing hole, so does not change the size of
the struct.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-3-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In case of a ZONE APPEND write, regardless of native ZONE APPEND or the
emulation layer in the zone write plugging code, the sector the data got
written to by the device needs to be updated in the bio.
At the moment, this is done for every native ZONE APPEND write and every
request that is flagged with 'BIO_ZONE_WRITE_PLUGGING'. But thus
superfluously updates the sector for regular writes to a zoned block
device.
Check if a bio is a native ZONE APPEND write or if the bio is flagged as
'BIO_EMULATES_ZONE_APPEND', meaning the block layer's zone write plugging
code handles the ZONE APPEND and translates it into a regular write and
back. Only if one of these two criterion is met, update the sector in the
bio upon completion.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/dea089581cb6b777c1cd1500b38ac0b61df4b2d1.1746530748.git.jth@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In case of a ZONE APPEND write, regardless of native ZONE APPEND or the
emulation layer in the zone write plugging code, the sector the data got
written to by the device needs to be updated in the bio.
At the moment, this is done for every native ZONE APPEND write and every
request that is flagged with 'BIO_ZONE_WRITE_PLUGGING'. But thus
superfluously updates the sector for regular writes to a zoned block
device.
Check if a bio is a native ZONE APPEND write or if the bio is flagged as
'BIO_EMULATES_ZONE_APPEND', meaning the block layer's zone write plugging
code handles the ZONE APPEND and translates it into a regular write and
back. Only if one of these two criterion is met, update the sector in the
bio upon completion.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/dea089581cb6b777c1cd1500b38ac0b61df4b2d1.1746530748.git.jth@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
scheduler's ->exit() is called with queue frozen and elevator lock is held, and
wbt_enable_default() can't be called with queue frozen, otherwise the
following lockdep warning is triggered:
#6 (&q->rq_qos_mutex){+.+.}-{4:4}:
#5 (&eq->sysfs_lock){+.+.}-{4:4}:
#4 (&q->elevator_lock){+.+.}-{4:4}:
#3 (&q->q_usage_counter(io)#3){++++}-{0:0}:
#2 (fs_reclaim){+.+.}-{0:0}:
#1 (&sb->s_type->i_mutex_key#3){+.+.}-{4:4}:
#0 (&q->debugfs_mutex){+.+.}-{4:4}:
Fix the issue by moving wbt_enable_default() out of bfq's exit(), and
call it from elevator_change_done().
Meantime add disk->rqos_state_mutex for covering wbt state change, which
matches the purpose more than ->elevator_lock.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-26-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move hctx cpuhp add/del out of queue freezing for not connecting freeze
lock with cpuhp locks, then lockdep warning can be avoided.
This way is safe because both needn't queue to be frozen and scheduler
switch isn't allowed, with same reason for moving hctx debugfs/sysfs
register out of queue freeze.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-25-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Both blk_mq_map_swqueue() and blk_mq_realloc_hw_ctxs() are called before
the request queue is added to tagset list, so the two won't run concurrently
with blk_mq_update_nr_hw_queues().
When the two functions are only called from queue initialization or
blk_mq_update_nr_hw_queues(), elevator switch can't happen.
So remove ->elevator_lock uses from the two functions.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-24-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move hctx debugfs/sysfs register out of freezing queue in
__blk_mq_update_nr_hw_queues(), so that the following lockdep dependency
can be killed:
#2 (&q->q_usage_counter(io)#16){++++}-{0:0}:
#1 (fs_reclaim){+.+.}-{0:0}:
#0 (&sb->s_type->i_mutex_key#3){+.+.}-{4:4}: //debugfs
And registering/un-registering hctx debugfs/sysfs does not require queue to
be frozen:
- hctx sysfs attributes show() are drained when removing kobject, and
there isn't store() implementation for hctx sysfs attributes
- debugfs entry read() is drained too when removing debugfs directory,
and there isn't write() implementation for hctx debugfs too
- so it is safe to register/unregister hctx sysfs/debugfs without
freezing queue because the cod paths changes nothing, and we just
need to keep hctx live
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-23-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move elv_register[unregister]_queue out of ->elevator_lock & queue freezing,
so we can kill many lockdep warnings.
elv_register[unregister]_queue() is serialized, and just dealing with sysfs/
debugfs things, no need to be done with queue frozen:
- when it is called from adding disk, elevator switch isn't possible
because ->queue_kobj isn't added yet
- when it is called from deleting disk, disable_elv_switch() is
responsible for preventing new elevator switch and draining old
elevator switch.
- when it is called from blk_mq_update_nr_hw_queues(), adding/removing
disk and elevator switch can't be allowed or in-progress
With this change, elevator's ->exit() is called before calling
elv_unregister_queue, then user may call into ->show()/store() of elevator's
sysfs attributes, and we have covered this issue by adding `ELEVATOR_FLAG_DYNG`.
For blk-mq debugfs, hctx->sched_tags is always checked with ->elevator_lock by
debugfs code, meantime hctx->sched_tags is updated with ->elevator_lock, so
there isn't such issue.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-22-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add new helper disable_elv_switch() and new flag QUEUE_FLAG_NO_ELV_SWITCH
for disabling elevator switch before deleting disk:
- originally flag QUEUE_FLAG_REGISTERED is added for preventing elevator
switch during removing disk, but this flag has been used widely for
other purposes, so add one new flag for disabling elevator switch only
- for avoiding deadlock risk, we have to move elevator queue
register/unregister out of elevator lock and queue freeze, which will be
done in next patch. However, this way adds small race window between elevator
switch and deleting ->queue_kobj, in which elevator queue register/unregister
could be run concurrently. The added helper will be used for avoiding the race
in the following patch.
- drain in-progress elevator switch before deleting disk
Suggested-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-21-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Prepare for moving elv_register[unregister]_queue out of elevator_lock
& queue freezing, so we may have to call elv_unregister_queue() after
elevator ->exit() is called, then there is small window for user to
call into ->show()/store(), and user-after-free can be caused.
Fail to show/store elevator sysfs attribute if elevator is dying by
adding one new flag of ELEVATOR_FLAG_DYNG, which is protected by
elevator ->sysfs_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-20-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
elevatore queue's type is assigned since its allocation, and never
get cleared until it is released.
So its ->type is always not NULL, remove the unnecessary check.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-19-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pass elevator_queue reference to elv_register_queue() & elv_unregister_queue().
No functional change, and prepare for moving the two out of elevator
lock & freezing queue, when we need to store the old & new elevator
queue in `struct elv_change_ctx` instance, then both two can co-exist
for short while, so we have to pass the exact elevator_queue instance
to elv_register_queue & unregister_queue.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-18-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Elevator change is one well-define behavior:
- tear down current elevator if it exists
- setup new elevator
It is supposed to cover any case for changing elevator by single
internal API, typically the following cases:
- setup default elevator in add_disk()
- switch to none in del_disk()
- reset elevator in blk_mq_update_nr_hw_queues()
- switch elevator in sysfs `store` elevator attribute
This patch uses elevator_change() to cover all above cases:
- every elevator switch is serialized with each other: add_disk/del_disk/
store elevator is serialized already, blk_mq_update_nr_hw_queues() uses
srcu for syncing with the other three cases
- for both add_disk()/del_disk(), queue freeze works at atomic mode
or has been froze, so the freeze in elevator_change() won't add extra
delay
- `struct elev_change_ctx` instance holds any info for changing elevator
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-17-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add `struct elv_change_ctx` and prepare for unifying elevator change by
elevator_change(). With this way, any input & output parameter can
be provided & observed in top helper.
This way helps to move kobject add/delete & debugfs register/unregister
out of ->elevator_lock & freezing queue.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-16-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move queue freezing & elevator_lock into elevator_change(), and prepare
for using elevator_change() for setting up & tearing down default elevator
too.
Also add lockdep_assert_held() in __elevator_change() because either
read or write lock is required for changing elevator.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-15-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In blk_mq_update_nr_hw_queues(), nr_hw_queues changes and elevator data
depends on it, and elevator has to be reattached, so call elevator_switch()
to force attachment.
Add elv_update_nr_hw_queues() simply for blk_mq_update_nr_hw_queues() to
reattach elevator, since elevator switch isn't likely when running
blk_mq_update_nr_hw_queues(). This way removes the current switch
none and switch back code.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-14-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move blk_queue_registered() check into elv_iosched_store() and prepare
for using elevator_change() for covering any kind of elevator change in
adding/deleting disk and updating nr_hw_queue.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-13-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This removes duplicate code, and keeps the callers tidy.
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-12-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
That makes the function nicely self-contained and can be used
to avoid code duplication.
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-11-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Both adding/deleting disk code are reader of `nr_hw_queues`, so we can't
allow them in-progress when updating nr_hw_queues, kernel panic and
kasan has been reported in [1].
Prevent adding/deleting disk during updating nr_hw_queues by adding
rw_semaphore to tagset, write lock is grabbed in blk_mq_update_nr_hw_queues(),
and read lock is acquired when adding/deleting disk.
Also mark GFP_NOIO allocation scope for adding/deleting disk because
blk_mq_update_nr_hw_queues() is part of some driver's error handler.
This way avoids lot of trouble.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Suggested-by: Nilay Shroff <nilay@linux.ibm.com>
Reported-by: Nilay Shroff <nilay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-block/a5896cdb-a59a-4a37-9f99-20522f5d2987@linux.ibm.com/
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-9-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add helper add_disk_final() for scanning partitions, announcing disk and
handling the last thing for adding disk.
No functional change, and prepare for prevent adding disk from happening
when updating nr_hw_queues.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-8-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
sched debugfs shares same lifetime with scheduler's kobject, and same
lock(elevator lock), so move sched debugfs register/unregister into
elevator_register_queue() and elevator_unregister_queue().
Then we needn't blk_mq_debugfs_register() for us to register sched
debugfs any more.
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-7-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add blk_mq_sched_reg_debugfs()/blk_mq_sched_unreg_debugfs() to clean up
sched init/exit code a bit.
Register & unregister debugfs for sched & sched_hctx order is changed a
bit, but it is safe because sched & sched_hctx is guaranteed to be ready
when exporting via debugfs.
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-6-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use q->elevator with ->elevator_lock held in elv_iosched_show(), since
the local cached elevator reference may become stale after getting
->elevator_lock.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-5-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Both elevator_switch() and elevator_disable() are only called from the
two code paths, in which queue is guaranteed to be frozen.
So don't call freeze queue in the two functions, also add asserts for
queue freeze.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ELEVATOR_FLAG_DISABLE_WBT is only used by BFQ to disallow wbt when BFQ is
in use. The flag is set in BFQ's init(), and cleared in BFQ's exit().
Making it as request queue flag, so that we can avoid to deal with elevator
switch race. Also it isn't graceful to checking one scheduler flag in
wbt_enable_default().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move blk_mq_add_queue_tag_set() after blk_mq_map_swqueue(), and publish
this request queue to tagset after everything is setup.
This way is safe because BLK_MQ_F_TAG_QUEUE_SHARED isn't used by
blk_mq_map_swqueue(), and this flag is mainly checked in fast IO code
path.
Prepare for removing ->elevator_lock from blk_mq_map_swqueue() which
is supposed to be called when elevator switch can't be done.
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reported-by: Nilay Shroff <nilay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-block/567cb7ab-23d6-4cee-a915-c8cdac903ddd@linux.ibm.com/
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now the tg->[bytes/io]_disp type is signed, and calculate_bytes/io_allowed
return type is unsigned. Even if the bps/iops limit is not set to max, the
return value of the function may still exceed INT_MAX or LLONG_MAX, which
can cause overflow in outer variables. In such cases, we can add additional
checks accordingly.
And in throtl_trim_slice(), if the BPS/IOPS limit is set to max, there's
no need to call calculate_bytes/io_allowed(). Introduces the helper
functions throtl_trim_bps/iops to simplifies the process. For cases when
the calculated trim value exceeds INT_MAX (causing an overflow), we reset
tg->[bytes/io]_disp to zero, so return original tg->[bytes/io]_disp because
it is the size that is actually trimmed.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250417132054.2866409-4-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We no longer need carryover_[bytes/ios] in tg, so it is removed. The
related comments about carryover in tg are also merged into
[bytes/io]_disp, and modify other related comments.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250417132054.2866409-3-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In commit 6cc477c368 ("blk-throttle: carry over directly"), the carryover
bytes/ios was be carried to [bytes/io]_disp. However, its update mechanism
has some issues.
In __tg_update_carryover(), we calculate "bytes" and "ios" to represent the
carryover, but the computation when updating [bytes/io]_disp is incorrect.
And if the sq->nr_queued is empty, we may not update tg->[bytes/io]_disp to
0 in tg_update_carryover(). We should set it to 0 in non carryover case.
This patch fixes the issue.
Fixes: 6cc477c368 ("blk-throttle: carry over directly")
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250417132054.2866409-2-wozizhi@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The block layer bounce buffering support is unused now, remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250505081138.3435992-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use writeback_iter instead of the deprecated write_cache_pages wrapper
in blkdev_writepages. This removes an indirect call per folio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20250424082752.1967679-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_mq_flush_plug_list() has a fast path if all requests in the plug
are destined for the same request_queue. It calls ->queue_rqs() with the
whole batch of requests, falling back on ->queue_rq() for any requests
not handled by ->queue_rqs(). However, if the requests are destined for
multiple queues, blk_mq_flush_plug_list() has a slow path that calls
blk_mq_dispatch_list() repeatedly to filter the requests by ctx/hctx.
Each queue's requests are inserted into the hctx's dispatch list under a
spinlock, then __blk_mq_sched_dispatch_requests() takes them out of the
dispatch list (taking the spinlock again), and finally
blk_mq_dispatch_rq_list() calls ->queue_rq() on each request.
Acquiring the hctx spinlock twice and calling ->queue_rq() instead of
->queue_rqs() makes the slow path significantly more expensive. Thus,
batching more requests into a single plug (e.g. io_uring_enter syscall)
can counterintuitively hurt performance by causing the plug to span
multiple queues. We have observed 2-3% of CPU time spent acquiring the
hctx spinlock alone on workloads issuing requests to multiple NVMe
devices in the same io_uring SQE batches.
Add a medium path in blk_mq_flush_plug_list() for plugs that don't have
elevators or come from a schedule, but do span multiple queues. Filter
the requests by queue and call ->queue_rqs()/->queue_rq() on the list of
requests destined to each request_queue.
With this change, we no longer see any CPU time spent in _raw_spin_lock
from blk_mq_flush_plug_list and throughput increases accordingly.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250426011728.4189119-4-csander@purestorage.com
[axboe: fix whitespace damage]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
