Use the %pg format specifier instead of the stack hungry bdevname
function, and remove handle_bad_sector given that it is not pointless.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220304180105.409765-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Don't use a WARN_ON when printing a potentially user triggered
condition. Also don't print the partno when the block device name
already includes it, and use the %pg specifier to simplify printing
the block device name.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220304180105.409765-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
No more users of REQ_OP_WRITE_SAME or drivers implementing it are left,
so remove the infrastructure.
[mkp: fold in and tweak sysfs reporting fix]
Link: https://lore.kernel.org/r/20220209082828.2629273-8-hch@lst.de
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Various block drivers call blk_set_queue_dying to mark a disk as dead due
to surprise removal events, but since commit 8e141f9eb8 that doesn't
work given that the GD_DEAD flag needs to be set to stop I/O.
Replace the driver calls to blk_set_queue_dying with a new (and properly
documented) blk_mark_disk_dead API, and fold blk_set_queue_dying into the
only remaining caller.
Fixes: 8e141f9eb8 ("block: drain file system I/O on del_gendisk")
Reported-by: Markus Blöchl <markus.bloechl@ipetronik.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20220217075231.1140-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now submit_bio_checks() is only called by submit_bio_noacct(), so merge
it into submit_bio_noacct().
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220216044514.2903784-6-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The bio has been checked already before throttling, so no need to check
it again before dispatching it from throttle queue.
Add a helper of submit_bio_noacct_nocheck() for this purpose.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220216044514.2903784-5-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
submit_bio_checks() won't be called outside of block/blk-core.c any more
since commit 9d497e2941 ("block: don't protect submit_bio_checks by
q_usage_counter"), so mark it as one local helper.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220216044514.2903784-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_crypto_bio_prep() is called for both bio based and blk-mq drivers,
so move it out of blk-mq.c, then we can unify this kind of handling.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220216044514.2903784-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is more clean & readable to check bio when starting to submit it,
instead of just before calling ->submit_bio() or blk_mq_submit_bio().
Also it provides us chance to optimize bio submission without checking
bio.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220216044514.2903784-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Partition include/linux/blk-cgroup.h into two parts: one is public part,
the other is block layer private part.
Suggested by Christoph Hellwig.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220211101149.2368042-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
q->blkg_list is only used by blkcg code, so move it into
blkcg_init_queue.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220211101149.2368042-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Change the user visible return value for BLK_STS_OFFLINE to -ENODEV, which
is more descriptive than existing -EIO.
Signed-off-by: Song Liu <song@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220203192827.1370270-3-song@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, drivers reports BLK_STS_IOERR for devices that are not full
online or being removed. This behavior could cause confusion for users,
as they are not really I/O errors from the device.
Solve this issue with a new state BLK_STS_OFFLINE, which reports "device
offline error" in dmesg instead of "I/O error".
EIO is intentionally kept to not change user visible return value.
Signed-off-by: Song Liu <song@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220203192827.1370270-2-song@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rename blk_flush_plug to __blk_flush_plug and add a wrapper that includes
the NULL check instead of open coding that check everywhere.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220127070549.1377856-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bio_start_io_acct_time() interface is like bio_start_io_acct() that
allows start_time to be passed in. This gives drivers the ability to
defer starting accounting until after IO is issued (but possibily not
entirely due to bio splitting).
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20220128155841.39644-2-snitzer@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit cc9c884dd7 ("block: call submit_bio_checks under q_usage_counter")
uses q_usage_counter to protect submit_bio_checks for avoiding IO after
disk is deleted by del_gendisk().
Turns out the protection isn't necessary, because once
blk_mq_freeze_queue_wait() in del_gendisk() returns:
1) all in-flight IO has been done
2) all new IO will be failed in __bio_queue_enter() because
q_usage_counter is dead, and GD_DEAD is set
3) both disk and request queue instance are safe since caller of
submit_bio() guarantees that the disk can't be closed.
Once submit_bio_checks() needn't the protection of q_usage_counter, we can
move submit_bio_checks before calling blk_mq_submit_bio() and
->submit_bio(). With this change, we needn't to throttle queue with
holding one allocated request, then precise driver tag or request won't be
wasted in throttling. Meantime we can unify the bio check for both bio
based and request based driver.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220104134223.590803-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In case of BLK_MQ_F_BLOCKING, per-hctx srcu is used to protect dispatch
critical area. However, this srcu instance stays at the end of hctx, and
it often takes standalone cacheline, often cold.
Inside srcu_read_lock() and srcu_read_unlock(), WRITE is always done on
the indirect percpu variable which is allocated from heap instead of
being embedded, srcu->srcu_idx is read only in srcu_read_lock(). It
doesn't matter if srcu structure stays in hctx or request queue.
So switch to per-request-queue srcu for protecting dispatch, and this
way simplifies quiesce a lot, not mention quiesce is always done on the
request queue wide.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211203131534.3668411-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The only user of the io_context for IO is BFQ, yet we put the checking
and logic of it into the normal IO path.
Put the creation into blk_mq_sched_assign_ioc(), and have BFQ use that
helper.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
All request based code is in the blk-mq files now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This function is only used by the request completion path. Factor out
a blk_status_to_str to keep blk_errors private in blk-core.c.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_dump_rq_flags deals with a request, so move it to blk-mq.c.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
These are only used for request based I/O, so move them where they are
used.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Keep all the request based code together.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_rq_init deals with a request structure, so move it to blk-mq.c
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Keep all the request based code together.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This function is trivial, and flush_dcache_page is always defined, so
just open code it in the 2.5 callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_rq_err_bytes is only used by the scsi midlayer, so move it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The build warning:
block/blk-core.c:968: warning: Function parameter or member 'iob'
not described in 'bio_poll'.
Fixes: 5a72e899ce ("block: add a struct io_comp_batch argument to fops->iopoll()")
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
KASAN reports a use-after-free report when doing block test:
==================================================================
[10050.967049] BUG: KASAN: use-after-free in
submit_bio_checks+0x1539/0x1550
[10050.977638] Call Trace:
[10050.978190] dump_stack+0x9b/0xce
[10050.979674] print_address_description.constprop.6+0x3e/0x60
[10050.983510] kasan_report.cold.9+0x22/0x3a
[10050.986089] submit_bio_checks+0x1539/0x1550
[10050.989576] submit_bio_noacct+0x83/0xc80
[10050.993714] submit_bio+0xa7/0x330
[10050.994435] mpage_readahead+0x380/0x500
[10050.998009] read_pages+0x1c1/0xbf0
[10051.002057] page_cache_ra_unbounded+0x4c2/0x6f0
[10051.007413] do_page_cache_ra+0xda/0x110
[10051.008207] force_page_cache_ra+0x23d/0x3d0
[10051.009087] page_cache_sync_ra+0xca/0x300
[10051.009970] generic_file_buffered_read+0xbea/0x2130
[10051.012685] generic_file_read_iter+0x315/0x490
[10051.014472] blkdev_read_iter+0x113/0x1b0
[10051.015300] aio_read+0x2ad/0x450
[10051.023786] io_submit_one+0xc8e/0x1d60
[10051.029855] __se_sys_io_submit+0x125/0x350
[10051.033442] do_syscall_64+0x2d/0x40
[10051.034156] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[10051.048733] Allocated by task 18598:
[10051.049482] kasan_save_stack+0x19/0x40
[10051.050263] __kasan_kmalloc.constprop.1+0xc1/0xd0
[10051.051230] kmem_cache_alloc+0x146/0x440
[10051.052060] mempool_alloc+0x125/0x2f0
[10051.052818] bio_alloc_bioset+0x353/0x590
[10051.053658] mpage_alloc+0x3b/0x240
[10051.054382] do_mpage_readpage+0xddf/0x1ef0
[10051.055250] mpage_readahead+0x264/0x500
[10051.056060] read_pages+0x1c1/0xbf0
[10051.056758] page_cache_ra_unbounded+0x4c2/0x6f0
[10051.057702] do_page_cache_ra+0xda/0x110
[10051.058511] force_page_cache_ra+0x23d/0x3d0
[10051.059373] page_cache_sync_ra+0xca/0x300
[10051.060198] generic_file_buffered_read+0xbea/0x2130
[10051.061195] generic_file_read_iter+0x315/0x490
[10051.062189] blkdev_read_iter+0x113/0x1b0
[10051.063015] aio_read+0x2ad/0x450
[10051.063686] io_submit_one+0xc8e/0x1d60
[10051.064467] __se_sys_io_submit+0x125/0x350
[10051.065318] do_syscall_64+0x2d/0x40
[10051.066082] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[10051.067455] Freed by task 13307:
[10051.068136] kasan_save_stack+0x19/0x40
[10051.068931] kasan_set_track+0x1c/0x30
[10051.069726] kasan_set_free_info+0x1b/0x30
[10051.070621] __kasan_slab_free+0x111/0x160
[10051.071480] kmem_cache_free+0x94/0x460
[10051.072256] mempool_free+0xd6/0x320
[10051.072985] bio_free+0xe0/0x130
[10051.073630] bio_put+0xab/0xe0
[10051.074252] bio_endio+0x3a6/0x5d0
[10051.074984] blk_update_request+0x590/0x1370
[10051.075870] scsi_end_request+0x7d/0x400
[10051.076667] scsi_io_completion+0x1aa/0xe50
[10051.077503] scsi_softirq_done+0x11b/0x240
[10051.078344] blk_mq_complete_request+0xd4/0x120
[10051.079275] scsi_mq_done+0xf0/0x200
[10051.080036] virtscsi_vq_done+0xbc/0x150
[10051.080850] vring_interrupt+0x179/0x390
[10051.081650] __handle_irq_event_percpu+0xf7/0x490
[10051.082626] handle_irq_event_percpu+0x7b/0x160
[10051.083527] handle_irq_event+0xcc/0x170
[10051.084297] handle_edge_irq+0x215/0xb20
[10051.085122] asm_call_irq_on_stack+0xf/0x20
[10051.085986] common_interrupt+0xae/0x120
[10051.086830] asm_common_interrupt+0x1e/0x40
==================================================================
Bio will be checked at beginning of submit_bio_noacct(). If bio needs
to be throttled, it will start the timer and stop submit bio directly.
Bio will submit in blk_throtl_dispatch_work_fn() when the timer expires.
But in the current process, if bio is throttled, it will still set bio
issue->value by blkcg_bio_issue_init(). This is redundant and may cause
the above use-after-free.
CPU0 CPU1
submit_bio
submit_bio_noacct
submit_bio_checks
blk_throtl_bio()
<=mod_timer(&sq->pending_timer
blk_throtl_dispatch_work_fn
submit_bio_noacct() <= bio have
throttle tag, will throw directly
and bio issue->value will be set
here
bio_endio()
bio_put()
bio_free() <= free this bio
blkcg_bio_issue_init(bio)
<= bio has been freed and
will lead to UAF
return BLK_QC_T_NONE
Fix this by remove extra blkcg_bio_issue_init.
Fixes: e439bedf6b (blkcg: consolidate bio_issue_init() to be a part of core)
Signed-off-by: Laibin Qiu <qiulaibin@huawei.com>
Link: https://lore.kernel.org/r/20211112093354.3581504-1-qiulaibin@huawei.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-5.16/block-2021-11-09' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- Set of fixes for the batched tag allocation (Ming, me)
- add_disk() error handling fix (Luis)
- Nested queue quiesce fixes (Ming)
- Shared tags init error handling fix (Ye)
- Misc cleanups (Jean, Ming, me)
* tag 'for-5.16/block-2021-11-09' of git://git.kernel.dk/linux-block:
nvme: wait until quiesce is done
scsi: make sure that request queue queiesce and unquiesce balanced
scsi: avoid to quiesce sdev->request_queue two times
blk-mq: add one API for waiting until quiesce is done
blk-mq: don't free tags if the tag_set is used by other device in queue initialztion
block: fix device_add_disk() kobject_create_and_add() error handling
block: ensure cached plug request matches the current queue
block: move queue enter logic into blk_mq_submit_bio()
block: make bio_queue_enter() fast-path available inline
block: split request allocation components into helpers
block: have plug stored requests hold references to the queue
blk-mq: update hctx->nr_active in blk_mq_end_request_batch()
blk-mq: add RQF_ELV debug entry
blk-mq: only try to run plug merge if request has same queue with incoming bio
block: move RQF_ELV setting into allocators
dm: don't stop request queue after the dm device is suspended
block: replace always false argument with 'false'
block: assign correct tag before doing prefetch of request
blk-mq: fix redundant check of !e expression
Retain the old logic for the fops based submit, but for our internal
blk_mq_submit_bio(), move the queue entering logic into the core
function itself.
We need to be a bit careful if going into the scheduler, as a scheduler
or queue mappings can arbitrarily change before we have entered the queue.
Have the bio scheduler mapping do that separately, it's a very cheap
operation compared to actually doing merging locking and lookups.
Reviewed-by: Christoph Hellwig <hch@lst.de>
[axboe: update to check merge post submit_bio_checks() doing remap...]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just a prep patch for shifting the queue enter logic. This moves the
expected fast path inline, and leaves __bio_queue_enter() as an
out-of-line function call. We don't want to inline the latter, as it's
mostly slow path code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Requests that were stored in the cache deliberately didn't hold an enter
reference to the queue, instead we grabbed one every time we pulled a
request out of there. That made for awkward logic on freeing the remainder
of the cached list, if needed, where we had to artificially raise the
queue usage count before each free.
Grab references up front for cached plug requests. That's safer, and also
more efficient.
Fixes: 47c122e35d ("block: pre-allocate requests if plug is started and is a batch")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
These are now pointless wrappers around blk_mq_{alloc,free}_request,
so remove them.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20211025070517.1548584-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_try_enter_queue() already takes rcu_read_lock/unlock, so we can
avoid the second pair in percpu_ref_tryget_live(), use a newly added
percpu_ref_tryget_live_rcu().
As rcu_read_lock/unlock imply barrier()s, it's pretty noticeable,
especially for for !CONFIG_PREEMPT_RCU (default for some distributions),
where __rcu_read_lock/unlock() are not inlined.
3.20% io_uring [kernel.vmlinux] [k] __rcu_read_unlock
3.05% io_uring [kernel.vmlinux] [k] __rcu_read_lock
2.52% io_uring [kernel.vmlinux] [k] __rcu_read_unlock
2.28% io_uring [kernel.vmlinux] [k] __rcu_read_lock
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6b11c67ea495ed9d44f067622d852de4a510ce65.1634822969.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Consolidate the various helpers into a single blk_flush_plug helper that
takes a plk_plug and the from_scheduler bool and switch all callsites to
call it directly. Checks that the plug is non-NULL must be performed by
the caller, something that most already do anyway.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211020144119.142582-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Don't call flush_plug_callbacks if there are no plug callbacks.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211020144119.142582-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
percpu_ref_put() are inlined for performance and bloat the binary, we
don't care about the fail case of blk_try_enter_queue(), so we can
replace it with a call to blk_queue_exit().
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Convert bdev->bd_disk->queue to bdev_get_queue(), which is faster.
Apparently, there are a few such spots in block that got lost during
rebases.
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we have just one queue type in the plug list, then we can extend our
direct issue to cover a full plug list as well. This allows sending a
batch of requests for direct issue, which is more efficient than doing
one-at-a-time kind of issue.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use a singly linked list for the blk_plug. This saves 8 bytes in the
blk_plug struct, and makes for faster list manipulations than doubly
linked lists. As we don't use the doubly linked lists for anything,
singly linked is just fine.
This yields a bump in default (merging enabled) performance from 7.0
to 7.1M IOPS, and ~7.5M IOPS with merging disabled.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
struct io_comp_batch contains a list head and a completion handler, which
will allow completions to more effciently completed batches of IO.
For now, no functional changes in this patch, we just define the
io_comp_batch structure and add the argument to the file_operations iopoll
handler.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For some reason we still have them in blk-core, with the rest of the
request completion being in blk-mq. That causes and out-of-line call
for each completion.
Move them into blk-mq.c instead, where they belong.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have exactly one caller of this, just get rid of adding the useless
function name to the output.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.
Polling for the bio itself leads to a few advantages:
- the cookie construction can made entirely private in blk-mq.c
- the caller does not need to remember the request_queue and cookie
separately and thus sidesteps their lifetime issues
- keeping the device and the cookie inside the bio allows to trivially
support polling BIOs remapping by stacking drivers
- a lot of code to propagate the cookie back up the submission path can
be removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Unlike the RWF_HIPRI userspace ABI which is intentionally kept vague,
the bio flag is specific to the polling implementation, so rename and
document it properly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The caller typically has a good (or even exact) idea of how many requests
it needs to submit. We can make the request/tag allocation a lot more
efficient if we just allocate N requests/tags upfront when we queue the
first bio from the batch.
Provide a new plug start helper that allows the caller to specify how many
IOs are expected. This sets plug->nr_ios, and we can use that for smarter
request allocation. The plug provides a holding spot for requests, and
request allocation will check it before calling into the normal request
allocation path.
The blk_finish_plug() is called, check if there are unused requests and
free them. This should not happen in normal operations. The exception is
if we get merging, then we may be left with requests that need freeing
when done.
This raises the per-core performance on my setup from ~5.8M to ~6.1M
IOPS.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Even if no policies are defined, we spend ~2% of the total IO time
checking. Move the fast path inline.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To be more concise and consistent in naming, rename
blk_mq_sched_free_requests() -> blk_mq_sched_free_rqs().
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/1633429419-228500-7-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is a bit confusing that there is BLKDEV_MAX_RQ and MAX_SCHED_RQ, as
the name BLKDEV_MAX_RQ would imply the max requests always, which it is
not.
Rename to BLKDEV_MAX_RQ to BLKDEV_DEFAULT_RQ, matching its usage - that being
the default number of requests assigned when allocating a request queue.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/1633429419-228500-3-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Make the bad sector information a little more useful by printing
current->comm to identify the caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20210928052755.113016-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Split the integrity/metadata handling definitions out into a new header.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-17-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Instead of delaying draining of file system I/O related items like the
blk-qos queues, the integrity read workqueue and timeouts only when the
request_queue is removed, do that when del_gendisk is called. This is
important for SCSI where the upper level drivers that control the gendisk
are separate entities, and the disk can be freed much earlier than the
request_queue, or can even be unbound without tearing down the queue.
Fixes: edb0872f44 ("block: move the bdi from the request_queue to the gendisk")
Reported-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210929071241.934472-5-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To prepare for fixing a gendisk shutdown race, open code the
blk_queue_enter logic in bio_queue_enter. This also removes the
pointless flags translation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210929071241.934472-4-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Factor out the code to try to get q_usage_counter without blocking into
a separate helper. Both to improve code readability and to prepare for
splitting bio_queue_enter from blk_queue_enter.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210929071241.934472-3-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Ensure all bios check the current values of the queue under freeze
protection, i.e. to make sure the zero capacity set by del_gendisk
is actually seen before dispatching to the driver.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210929071241.934472-2-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'io_uring-bio-cache.5-2021-08-30' of git://git.kernel.dk/linux-block
Pull support for struct bio recycling from Jens Axboe:
"This adds bio recycling support for polled IO, allowing quick reuse of
a bio for high IOPS scenarios via a percpu bio_set list.
It's good for almost a 10% improvement in performance, bumping our
per-core IO limit from ~3.2M IOPS to ~3.5M IOPS"
* tag 'io_uring-bio-cache.5-2021-08-30' of git://git.kernel.dk/linux-block:
bio: improve kerneldoc documentation for bio_alloc_kiocb()
block: provide bio_clear_hipri() helper
block: use the percpu bio cache in __blkdev_direct_IO
io_uring: enable use of bio alloc cache
block: clear BIO_PERCPU_CACHE flag if polling isn't supported
bio: add allocation cache abstraction
fs: add kiocb alloc cache flag
bio: optimize initialization of a bio
Any case that turns off REQ_HIPRI must also clear BIO_PERCPU_CACHE,
as non-polled IO may complete through hard/soft IRQ and hence isn't
safe for our polled bio alloc cache.
Provide a helper that does just that, and use it in the merging code as
well if we split a bio and turn off polling.
Fixes: be863b9e43 ("block: clear BIO_PERCPU_CACHE flag if polling isn't supported")
Reported-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The bio alloc cache relies on the fact that a polled bio will complete
in process context, clear the cacheable flag if we disable polling
for a given bio.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For fixing use-after-free during iterating over requests, we grabbed
request's refcount before calling ->fn in commit 2e315dc07d ("blk-mq:
grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter").
Turns out this way may cause kernel panic when iterating over one flush
request:
1) old flush request's tag is just released, and this tag is reused by
one new request, but ->rqs[] isn't updated yet
2) the flush request can be re-used for submitting one new flush command,
so blk_rq_init() is called at the same time
3) meantime blk_mq_queue_tag_busy_iter() is called, and old flush request
is retrieved from ->rqs[tag]; when blk_mq_put_rq_ref() is called,
flush_rq->end_io may not be updated yet, so NULL pointer dereference
is triggered in blk_mq_put_rq_ref().
Fix the issue by calling refcount_set(&flush_rq->ref, 1) after
flush_rq->end_io is set. So far the only other caller of blk_rq_init() is
scsi_ioctl_reset() in which the request doesn't enter block IO stack and
the request reference count isn't used, so the change is safe.
Fixes: 2e315dc07d ("blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter")
Reported-by: "Blank-Burian, Markus, Dr." <blankburian@uni-muenster.de>
Tested-by: "Blank-Burian, Markus, Dr." <blankburian@uni-muenster.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/20210811142624.618598-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The backing device information only makes sense for file system I/O,
and thus belongs into the gendisk and not the lower level request_queue
structure. Move it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210809141744.1203023-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Don't leak the detaіls of the timer into the block layer, instead
initialize the timer in bdi_alloc and delete it in bdi_unregister.
Note that this means the timer is initialized (but not armed) for
non-block queues as well now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210809141744.1203023-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
On the IO submission path, blk_account_io_start() may interrupt
the system interruption. When the interruption returns, the value
of part->stamp may have been updated by other cores, so the time
value collected before the interruption may be less than part->
stamp. So when this happens, we should do nothing to make io_ticks
more accurate? For kernels less than 5.0, this may cause io_ticks
to become smaller, which in turn may cause abnormal ioutil values.
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/1625521646-1069-1-git-send-email-brookxu.cn@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With the legacy IDE driver gone drivers now use either REQ_OP_DRV_*
or REQ_OP_SCSI_*, so unify the two concepts of passthrough requests
into a single one.
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Although the original intent was to use blk_update_request() in stacking
block drivers only, it is used much more widely today. Reflect this in the
documentation block above this function. See also:
* commit 32fab448e5 ("block: add request update interface").
* commit 2e60e02297 ("block: clean up request completion API").
* commit ed6565e734 ("block: handle partial completions for special
payload requests").
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20210519175226.8853-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_alloc_queue is just an internal helper now, unexport it and remove
it from the public header.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-27-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have already delete block_dump feature in mark_inode_dirty() because
it can be replaced by tracepoints, now we also remove the part in
submit_bio() for the same reason. The part of block dump feature in
submit_bio() dump the write process, write region and sectors on the
target disk into kernel message. it can be replaced by
block_bio_queue tracepoint in submit_bio_checks(), so we do not need
block_dump anymore, remove the whole block_dump feature.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210313030146.2882027-3-yi.zhang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Get rid of all the PFN arithmetics and just use an enum for the two
remaining options, and use PageHighMem for the actual bounce decision.
Add a fast path to entirely avoid the call for the common case of a queue
not using the legacy bouncing code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20210331073001.46776-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Get rid of the wrapper for trace_block_rq_insert() and call the function
directly.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When an already remapped bio is resubmitted (e.g. by blk_queue_split),
bio_check_eod will compare the remapped bi_sector against the size
of the partition, leading to spurious I/O failures.
Skip the EOD check in this case.
Fixes: 309dca309f ("block: store a block_device pointer in struct bio")
Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
q->bio_split is only used by bio_split() for fast cloning bio, and no
need to allocate bvecs, so remove this flag.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Tested-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove the reverse map from a sector to a partition for I/O accounting by
simply using ->bi_bdev.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rework the I/O accounting for bio based drivers to use ->bi_bdev. This
means all drivers can now simply use bio_start_io_acct to start
accounting, and it will take partitions into account automatically. To
end I/O account either bio_end_io_acct can be used if the driver never
remaps I/O to a different device, or bio_end_io_acct_remapped if the
driver did remap the I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no good reason to reassign ->bi_bdev when remapping the
partition-relative block number to the device wide one, as all the
information required by the drivers comes from the gendisk anyway.
Keeping the original ->bi_bdev alive will allow to greatly simplify
the partition-away I/O accounting.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge a few checks for whole devices vs partitions to streamline the
sanity checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device. From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 20bd1d026a ("scsi: sd: Keep disk read-only when re-reading
partition") addressed a long-standing problem with user read-only
policy being overridden as a result of a device-initiated revalidate.
The commit has since been reverted due to a regression that left some
USB devices read-only indefinitely.
To fix the underlying problems with revalidate we need to keep track
of hardware state and user policy separately.
The gendisk has been updated to reflect the current hardware state set
by the device driver. This is done to allow returning the device to
the hardware state once the user clears the BLKROSET flag.
The resulting semantics are as follows:
- If BLKROSET sets a given partition read-only, that partition will
remain read-only even if the underlying storage stack initiates a
revalidate. However, the BLKRRPART ioctl will cause the partition
table to be dropped and any user policy on partitions will be lost.
- If BLKROSET has not been set, both the whole disk device and any
partitions will reflect the current write-protect state of the
underlying device.
Based on a patch from Martin K. Petersen <martin.petersen@oracle.com>.
Reported-by: Oleksii Kurochko <olkuroch@cisco.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201221
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is a load of driver fixes (12 ufs, 1 mpt3sas, 1 cxgbi). The big
core two fixes are for power management ("block: Do not accept any
requests while suspended" and "block: Fix a race in the runtime power
management code") which finally sorts out the resume problems we've
occasionally been having. To make the resume fix, there are seven
necessary precursors which effectively renames REQ_PREEMPT to REQ_PM,
so every "special" request in block is automatically a power
management exempt one. All of the non-PM preempt cases are removed
except for the one in the SCSI Parallel Interface (spi) domain
validation which is a genuine case where we have to run requests at
high priority to validate the bus so this becomes an autopm get/put
protected request.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is a load of driver fixes (12 ufs, 1 mpt3sas, 1 cxgbi).
The big core two fixes are for power management ("block: Do not accept
any requests while suspended" and "block: Fix a race in the runtime
power management code") which finally sorts out the resume problems
we've occasionally been having.
To make the resume fix, there are seven necessary precursors which
effectively renames REQ_PREEMPT to REQ_PM, so every "special" request
in block is automatically a power management exempt one.
All of the non-PM preempt cases are removed except for the one in the
SCSI Parallel Interface (spi) domain validation which is a genuine
case where we have to run requests at high priority to validate the
bus so this becomes an autopm get/put protected request"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (22 commits)
scsi: cxgb4i: Fix TLS dependency
scsi: ufs: Un-inline ufshcd_vops_device_reset function
scsi: ufs: Re-enable WriteBooster after device reset
scsi: ufs-mediatek: Use correct path to fix compile error
scsi: mpt3sas: Signedness bug in _base_get_diag_triggers()
scsi: block: Do not accept any requests while suspended
scsi: block: Remove RQF_PREEMPT and BLK_MQ_REQ_PREEMPT
scsi: core: Only process PM requests if rpm_status != RPM_ACTIVE
scsi: scsi_transport_spi: Set RQF_PM for domain validation commands
scsi: ide: Mark power management requests with RQF_PM instead of RQF_PREEMPT
scsi: ide: Do not set the RQF_PREEMPT flag for sense requests
scsi: block: Introduce BLK_MQ_REQ_PM
scsi: block: Fix a race in the runtime power management code
scsi: ufs-pci: Enable UFSHCD_CAP_RPM_AUTOSUSPEND for Intel controllers
scsi: ufs-pci: Fix recovery from hibernate exit errors for Intel controllers
scsi: ufs-pci: Ensure UFS device is in PowerDown mode for suspend-to-disk ->poweroff()
scsi: ufs-pci: Fix restore from S4 for Intel controllers
scsi: ufs-mediatek: Keep VCC always-on for specific devices
scsi: ufs: Allow regulators being always-on
scsi: ufs: Clear UAC for RPMB after ufshcd resets
...
blk_queue_enter() accepts BLK_MQ_REQ_PM requests independent of the runtime
power management state. Now that SCSI domain validation no longer depends
on this behavior, modify the behavior of blk_queue_enter() as follows:
- Do not accept any requests while suspended.
- Only process power management requests while suspending or resuming.
Submitting BLK_MQ_REQ_PM requests to a device that is runtime suspended
causes runtime-suspended devices not to resume as they should. The request
which should cause a runtime resume instead gets issued directly, without
resuming the device first. Of course the device can't handle it properly,
the I/O fails, and the device remains suspended.
The problem is fixed by checking that the queue's runtime-PM status isn't
RPM_SUSPENDED before allowing a request to be issued, and queuing a
runtime-resume request if it is. In particular, the inline
blk_pm_request_resume() routine is renamed blk_pm_resume_queue() and the
code is unified by merging the surrounding checks into the routine. If the
queue isn't set up for runtime PM, or there currently is no restriction on
allowed requests, the request is allowed. Likewise if the BLK_MQ_REQ_PM
flag is set and the status isn't RPM_SUSPENDED. Otherwise a runtime resume
is queued and the request is blocked until conditions are more suitable.
[ bvanassche: modified commit message and removed Cc: stable because
without the previous patches from this series this patch would break
parallel SCSI domain validation + introduced queue_rpm_status() ]
Link: https://lore.kernel.org/r/20201209052951.16136-9-bvanassche@acm.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Can Guo <cang@codeaurora.org>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-and-tested-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Remove flag RQF_PREEMPT and BLK_MQ_REQ_PREEMPT since these are no longer
used by any kernel code.
Link: https://lore.kernel.org/r/20201209052951.16136-8-bvanassche@acm.org
Cc: Can Guo <cang@codeaurora.org>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Martin Kepplinger <martin.kepplinger@puri.sm>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Introduce the BLK_MQ_REQ_PM flag. This flag makes the request allocation
functions set RQF_PM. This is the first step towards removing
BLK_MQ_REQ_PREEMPT.
Link: https://lore.kernel.org/r/20201209052951.16136-3-bvanassche@acm.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Can Guo <cang@codeaurora.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The request_queue can trivially be derived from the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The block_bio_merge tracepoint class can be reused for most bio-based
tracepoints. For that it just needs to lose the superfluous q and rq
parameters.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use struct block_device to lookup partitions on a disk. This removes
all usage of struct hd_struct from the I/O path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: Chao Yu <yuchao0@huawei.com> [f2fs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allocate hd_struct together with struct block_device to pre-load
the lifetime rule changes in preparation of merging the two structures.
Note that part0 was previously embedded into struct gendisk, but is
a separate allocation now, and already points to the block_device instead
of the hd_struct. The lifetime of struct gendisk is still controlled by
the struct device embedded in the part0 hd_struct.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the policy field to struct block_device and rename it to the
more descriptive bd_read_only. Also turn the field into a bool as it
is used as such.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the make_it_fail flag to struct block_device an turn it into a bool
in preparation of killing struct hd_struct.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the start_sect field to struct block_device in preparation
of killing struct hd_struct.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the dkstats and stamp field to struct block_device in preparation
of killing struct hd_struct.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that the hd_struct always has a block device attached to it, there is
no need for having two size field that just get out of sync.
Additionally the field in hd_struct did not use proper serialization,
possibly allowing for torn writes. By only using the block_device field
this problem also gets fixed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: Chao Yu <yuchao0@huawei.com> [f2fs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A zoned device with limited resources to open or activate zones may
return an error when the host exceeds those limits. The same command may
be successful if retried later, but the host needs to wait for specific
zone states before it should expect a retry to succeed. Have the block
layer provide an appropriate status for these conditions so applications
can distinuguish this error for special handling.
Cc: linux-api@vger.kernel.org
Cc: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
syzbot is reporting unkillable task [1], for the caller is failing to
handle a corrupted filesystem image which attempts to access beyond
the end of the device. While we need to fix the caller, flooding the
console with handle_bad_sector() message is unlikely useful.
[1] https://syzkaller.appspot.com/bug?id=f1f49fb971d7a3e01bd8ab8cff2ff4572ccf3092
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_crypto_rq_bio_prep() assumes its gfp_mask argument always includes
__GFP_DIRECT_RECLAIM, so that the mempool_alloc() will always succeed.
However, blk_crypto_rq_bio_prep() might be called with GFP_ATOMIC via
setup_clone() in drivers/md/dm-rq.c.
This case isn't currently reachable with a bio that actually has an
encryption context. However, it's fragile to rely on this. Just make
blk_crypto_rq_bio_prep() able to fail.
Suggested-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Satya Tangirala <satyat@google.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add QUEUE_FLAG_NOWAIT to allow a block device to advertise support for
REQ_NOWAIT. Bio-based devices may set QUEUE_FLAG_NOWAIT where
applicable.
Update QUEUE_FLAG_MQ_DEFAULT to include QUEUE_FLAG_NOWAIT. Also
update submit_bio_checks() to verify it is set for REQ_NOWAIT bios.
Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just checking SB_I_CGROUPWB for cgroup writeback support is enough.
Either the file system allocates its own bdi (e.g. btrfs), in which case
it is known to support cgroup writeback, or the bdi comes from the block
layer, which always supports cgroup writeback.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Set up a readahead size by default, as very few users have a good
reason to change it. This means code, ecryptfs, and orangefs now
set up the values while they were previously missing it, while ubifs,
mtd and vboxsf manually set it to 0 to avoid readahead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: Richard Weinberger <richard@nod.at> [ubifs, mtd]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
These functions can be used to enable iostat for partitions on devices
like md, bcache.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The per-hctx nr_active value can no longer be used to fairly assign a share
of tag depth per request queue for when using a shared sbitmap, as it does
not consider that the tags are shared tags over all hctx's.
For this case, record the nr_active_requests per request_queue, and make
the judgement based on that value.
Co-developed-with: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Tested-by: Don Brace<don.brace@microsemi.com> #SCSI resv cmds patches used
Tested-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If WRITE_ZERO/WRITE_SAME operation is not supported by the storage,
blk_cloned_rq_check_limits() will return IO error which will cause
device-mapper to fail the paths.
Instead, if the queue limit is set to 0, return BLK_STS_NOTSUPP.
BLK_STS_NOTSUPP will be ignored by device-mapper and will not fail the
paths.
Suggested-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Ritika Srivastava <ritika.srivastava@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's better to move bio merge related functions into blk-merge.c,
which contains all merge related functions.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If a driver leaves the limit settings as the defaults, then we don't
initialize bdi->io_pages. This means that file systems may need to
work around bdi->io_pages == 0, which is somewhat messy.
Initialize the default value just like we do for ->ra_pages.
Cc: stable@vger.kernel.org
Fixes: 9491ae4aad ("mm: don't cap request size based on read-ahead setting")
Reported-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-5.9/io_uring-20200802' of git://git.kernel.dk/linux-block
Pull io_uring updates from Jens Axboe:
"Lots of cleanups in here, hardening the code and/or making it easier
to read and fixing bugs, but a core feature/change too adding support
for real async buffered reads. With the latter in place, we just need
buffered write async support and we're done relying on kthreads for
the fast path. In detail:
- Cleanup how memory accounting is done on ring setup/free (Bijan)
- sq array offset calculation fixup (Dmitry)
- Consistently handle blocking off O_DIRECT submission path (me)
- Support proper async buffered reads, instead of relying on kthread
offload for that. This uses the page waitqueue to drive retries
from task_work, like we handle poll based retry. (me)
- IO completion optimizations (me)
- Fix race with accounting and ring fd install (me)
- Support EPOLLEXCLUSIVE (Jiufei)
- Get rid of the io_kiocb unionizing, made possible by shrinking
other bits (Pavel)
- Completion side cleanups (Pavel)
- Cleanup REQ_F_ flags handling, and kill off many of them (Pavel)
- Request environment grabbing cleanups (Pavel)
- File and socket read/write cleanups (Pavel)
- Improve kiocb_set_rw_flags() (Pavel)
- Tons of fixes and cleanups (Pavel)
- IORING_SQ_NEED_WAKEUP clear fix (Xiaoguang)"
* tag 'for-5.9/io_uring-20200802' of git://git.kernel.dk/linux-block: (127 commits)
io_uring: flip if handling after io_setup_async_rw
fs: optimise kiocb_set_rw_flags()
io_uring: don't touch 'ctx' after installing file descriptor
io_uring: get rid of atomic FAA for cq_timeouts
io_uring: consolidate *_check_overflow accounting
io_uring: fix stalled deferred requests
io_uring: fix racy overflow count reporting
io_uring: deduplicate __io_complete_rw()
io_uring: de-unionise io_kiocb
io-wq: update hash bits
io_uring: fix missing io_queue_linked_timeout()
io_uring: mark ->work uninitialised after cleanup
io_uring: deduplicate io_grab_files() calls
io_uring: don't do opcode prep twice
io_uring: clear IORING_SQ_NEED_WAKEUP after executing task works
io_uring: batch put_task_struct()
tasks: add put_task_struct_many()
io_uring: return locked and pinned page accounting
io_uring: don't miscount pinned memory
io_uring: don't open-code recv kbuf managment
...
If blk_mq_submit_bio flushes the plug list, bios for other disks can
show up on current->bio_list. As that doesn't involve any stacking of
block device it is entirely harmless and we should not warn about
this case.
Fixes: ff93ea0ce7 ("block: shortcut __submit_bio_noacct for blk-mq drivers")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bio_alloc_bioset references current->bio_list[1], so we need to
initialize it for the blk-mq submission path as well.
Fixes: ff93ea0ce7 ("block: shortcut __submit_bio_noacct for blk-mq drivers")
Reported-by: Qian Cai <cai@lca.pw>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that submit_bio_noacct has a decent blk-mq fast path there is no
more need for this bypass.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For blk-mq drivers bios can only be inserted for the same queue. So
bypass the complicated sorting logic in __submit_bio_noacct with
a blk-mq simpler submission helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Split out a __submit_bio_noacct helper for the actual de-recursion
algorithm, and simplify the loop by using a continue when we can't
enter the queue for a bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The make_request_fn is a little weird in that it sits directly in
struct request_queue instead of an operation vector. Replace it with
a block_device_operations method called submit_bio (which describes much
better what it does). Also remove the request_queue argument to it, as
the queue can be derived pretty trivially from the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The variable is only used once, so just open code the bio_sector()
there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
All registers disks must have a valid queue pointer, so don't bother to
log a warning for that case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The "generic_make_request: " prefix has no value, and will soon become
stale.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blkcg_bio_issue_check is a giant inline function that does three entirely
different things. Factor out the blk-cgroup related bio initalization
into a new helper, and the open code the sequence in the only caller,
relying on the fact that all the actual functionality is stubbed out for
non-cgroup builds.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We were only creating the request_queue debugfs_dir only
for make_request block drivers (multiqueue), but never for
request-based block drivers. We did this as we were only
creating non-blktrace additional debugfs files on that directory
for make_request drivers. However, since blktrace *always* creates
that directory anyway, we special-case the use of that directory
on blktrace. Other than this being an eye-sore, this exposes
request-based block drivers to the same debugfs fragile
race that used to exist with make_request block drivers
where if we start adding files onto that directory we can later
run a race with a double removal of dentries on the directory
if we don't deal with this carefully on blktrace.
Instead, just simplify things by always creating the request_queue
debugfs_dir on request_queue registration. Rename the mutex also to
reflect the fact that this is used outside of the blktrace context.
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit dc9edc44de ("block: Fix a blk_exit_rl() regression") merged on
v4.12 moved the work behind blk_release_queue() into a workqueue after a
splat floated around which indicated some work on blk_release_queue()
could sleep in blk_exit_rl(). This splat would be possible when a driver
called blk_put_queue() or blk_cleanup_queue() (which calls blk_put_queue()
as its final call) from an atomic context.
blk_put_queue() decrements the refcount for the request_queue kobject, and
upon reaching 0 blk_release_queue() is called. Although blk_exit_rl() is
now removed through commit db6d995235 ("block: remove request_list code")
on v5.0, we reserve the right to be able to sleep within
blk_release_queue() context.
The last reference for the request_queue must not be called from atomic
context. *When* the last reference to the request_queue reaches 0 varies,
and so let's take the opportunity to document when that is expected to
happen and also document the context of the related calls as best as
possible so we can avoid future issues, and with the hopes that the
synchronous request_queue removal sticks.
We revert back to synchronous request_queue removal because asynchronous
removal creates a regression with expected userspace interaction with
several drivers. An example is when removing the loopback driver, one
uses ioctls from userspace to do so, but upon return and if successful,
one expects the device to be removed. Likewise if one races to add another
device the new one may not be added as it is still being removed. This was
expected behavior before and it now fails as the device is still present
and busy still. Moving to asynchronous request_queue removal could have
broken many scripts which relied on the removal to have been completed if
there was no error. Document this expectation as well so that this
doesn't regress userspace again.
Using asynchronous request_queue removal however has helped us find
other bugs. In the future we can test what could break with this
arrangement by enabling CONFIG_DEBUG_KOBJECT_RELEASE.
While at it, update the docs with the context expectations for the
request_queue / gendisk refcount decrement, and make these
expectations explicit by using might_sleep().
Fixes: dc9edc44de ("block: Fix a blk_exit_rl() regression")
Suggested-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: yu kuai <yukuai3@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Let us clarify the context under which the helpers to increment the
refcount for the gendisk and request_queue can be called under. We
make this explicit on the places where we may sleep with might_sleep().
We don't address the decrement context yet, as that needs some extra
work and fixes, but will be addressed in the next patch.
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This adds documentation for the gendisk / request_queue refcount
helpers.
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Provide a way for the caller to specify that IO should be marked
with REQ_NOWAIT to avoid blocking on allocation.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
"Core block changes that have been queued up for this release:
- Remove dead blk-throttle and blk-wbt code (Guoqing)
- Include pid in blktrace note traces (Jan)
- Don't spew I/O errors on wouldblock termination (me)
- Zone append addition (Johannes, Keith, Damien)
- IO accounting improvements (Konstantin, Christoph)
- blk-mq hardware map update improvements (Ming)
- Scheduler dispatch improvement (Salman)
- Inline block encryption support (Satya)
- Request map fixes and improvements (Weiping)
- blk-iocost tweaks (Tejun)
- Fix for timeout failing with error injection (Keith)
- Queue re-run fixes (Douglas)
- CPU hotplug improvements (Christoph)
- Queue entry/exit improvements (Christoph)
- Move DMA drain handling to the few drivers that use it (Christoph)
- Partition handling cleanups (Christoph)"
* tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block: (127 commits)
block: mark bio_wouldblock_error() bio with BIO_QUIET
blk-wbt: rename __wbt_update_limits to wbt_update_limits
blk-wbt: remove wbt_update_limits
blk-throttle: remove tg_drain_bios
blk-throttle: remove blk_throtl_drain
null_blk: force complete for timeout request
blk-mq: drain I/O when all CPUs in a hctx are offline
blk-mq: add blk_mq_all_tag_iter
blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx
blk-mq: use BLK_MQ_NO_TAG in more places
blk-mq: rename BLK_MQ_TAG_FAIL to BLK_MQ_NO_TAG
blk-mq: move more request initialization to blk_mq_rq_ctx_init
blk-mq: simplify the blk_mq_get_request calling convention
blk-mq: remove the bio argument to ->prepare_request
nvme: force complete cancelled requests
blk-mq: blk-mq: provide forced completion method
block: fix a warning when blkdev.h is included for !CONFIG_BLOCK builds
block: blk-crypto-fallback: remove redundant initialization of variable err
block: reduce part_stat_lock() scope
block: use __this_cpu_add() instead of access by smp_processor_id()
...
Patch series "Change readahead API", v11.
This series adds a readahead address_space operation to replace the
readpages operation. The key difference is that pages are added to the
page cache as they are allocated (and then looked up by the filesystem)
instead of passing them on a list to the readpages operation and having
the filesystem add them to the page cache. It's a net reduction in code
for each implementation, more efficient than walking a list, and solves
the direct-write vs buffered-read problem reported by yu kuai at
http://lkml.kernel.org/r/20200116063601.39201-1-yukuai3@huawei.com
The only unconverted filesystems are those which use fscache. Their
conversion is pending Dave Howells' rewrite which will make the
conversion substantially easier. This should be completed by the end of
the year.
I want to thank the reviewers/testers; Dave Chinner, John Hubbard, Eric
Biggers, Johannes Thumshirn, Dave Sterba, Zi Yan, Christoph Hellwig and
Miklos Szeredi have done a marvellous job of providing constructive
criticism.
These patches pass an xfstests run on ext4, xfs & btrfs with no
regressions that I can tell (some of the tests seem a little flaky
before and remain flaky afterwards).
This patch (of 25):
The readahead code is part of the page cache so should be found in the
pagemap.h file. force_page_cache_readahead is only used within mm, so
move it to mm/internal.h instead. Remove the parameter names where they
add no value, and rename the ones which were actively misleading.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Link: http://lkml.kernel.org/r/20200414150233.24495-1-willy@infradead.org
Link: http://lkml.kernel.org/r/20200414150233.24495-2-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit c58c1f8343.
io_uring does do the right thing for this case, and we're still returning
-EAGAIN to userspace for the cases we don't support. Revert this change
to avoid doing endless spins of resubmits.
Cc: stable@vger.kernel.org # v5.6
Reported-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We only need the stats lock (aka preempt_disable()) for updating the
states, not for looking up or dropping the hd_struct reference.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the non-"new_io" branch of blk_account_io_start() into separate
function. Fix merge accounting for discards (they were counted as write
merges).
The new blk_account_io_merge_bio() doesn't call update_io_ticks() unlike
blk_account_io_start(), as there is no reason for that.
[hch: rebased]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
All callers are in blk-core.c, so move update_io_ticks over.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add two new helpers to simplify I/O accounting for bio based drivers.
Currently these drivers use the generic_start_io_acct and
generic_end_io_acct helpers which have very cumbersome calling
conventions, don't actually return the time they started accounting,
and try to deal with accounting for partitions, which can't happen
for bio based drivers. The new helpers will be used to subsequently
replace uses of the old helpers.
The main API is the bio based wrappes in blkdev.h, but for zram
which wants to account rw_page based I/O lower level routines are
provided as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
part_inc_in_flight and part_dec_in_flight are no-ops for blk-mq queues,
so remove the calls in purely blk-mq callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_mq_make_request currently needs to grab an q_usage_counter
reference when allocating a request. This is because the block layer
grabs one before calling blk_mq_make_request, but also releases it as
soon as blk_mq_make_request returns. Remove the blk_queue_exit call
after blk_mq_make_request returns, and instead let it consume the
reference. This works perfectly fine for the block layer caller, just
device mapper needs an extra reference as the old problem still
persists there. Open code blk_queue_enter_live in device mapper,
as there should be no other callers and this allows better documenting
why we do a non-try get.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We must have some way of letting a storage device driver know what
encryption context it should use for en/decrypting a request. However,
it's the upper layers (like the filesystem/fscrypt) that know about and
manages encryption contexts. As such, when the upper layer submits a bio
to the block layer, and this bio eventually reaches a device driver with
support for inline encryption, the device driver will need to have been
told the encryption context for that bio.
We want to communicate the encryption context from the upper layer to the
storage device along with the bio, when the bio is submitted to the block
layer. To do this, we add a struct bio_crypt_ctx to struct bio, which can
represent an encryption context (note that we can't use the bi_private
field in struct bio to do this because that field does not function to pass
information across layers in the storage stack). We also introduce various
functions to manipulate the bio_crypt_ctx and make the bio/request merging
logic aware of the bio_crypt_ctx.
We also make changes to blk-mq to make it handle bios with encryption
contexts. blk-mq can merge many bios into the same request. These bios need
to have contiguous data unit numbers (the necessary changes to blk-merge
are also made to ensure this) - as such, it suffices to keep the data unit
number of just the first bio, since that's all a storage driver needs to
infer the data unit number to use for each data block in each bio in a
request. blk-mq keeps track of the encryption context to be used for all
the bios in a request with the request's rq_crypt_ctx. When the first bio
is added to an empty request, blk-mq will program the encryption context
of that bio into the request_queue's keyslot manager, and store the
returned keyslot in the request's rq_crypt_ctx. All the functions to
operate on encryption contexts are in blk-crypto.c.
Upper layers only need to call bio_crypt_set_ctx with the encryption key,
algorithm and data_unit_num; they don't have to worry about getting a
keyslot for each encryption context, as blk-mq/blk-crypto handles that.
Blk-crypto also makes it possible for request-based layered devices like
dm-rq to make use of inline encryption hardware by cloning the
rq_crypt_ctx and programming a keyslot in the new request_queue when
necessary.
Note that any user of the block layer can submit bios with an
encryption context, such as filesystems, device-mapper targets, etc.
Signed-off-by: Satya Tangirala <satyat@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_io_schedule() isn't called from performance sensitive code path, and
it is easier to maintain by exporting it as symbol.
Also blk_io_schedule() is only called by CONFIG_BLOCK code, so it is safe
to do this way. Meantime fixes build failure when CONFIG_BLOCK is off.
Cc: Christoph Hellwig <hch@infradead.org>
Fixes: e6249cdd46 ("block: add blk_io_schedule() for avoiding task hung in sync dio")
Reported-by: Satya Tangirala <satyat@google.com>
Tested-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Define REQ_OP_ZONE_APPEND to append-write sectors to a zone of a zoned
block device. This is a no-merge write operation.
A zone append write BIO must:
* Target a zoned block device
* Have a sector position indicating the start sector of the target zone
* The target zone must be a sequential write zone
* The BIO must not cross a zone boundary
* The BIO size must not be split to ensure that a single range of LBAs
is written with a single command.
Implement these checks in generic_make_request_checks() using the
helper function blk_check_zone_append(). To avoid write append BIO
splitting, introduce the new max_zone_append_sectors queue limit
attribute and ensure that a BIO size is always lower than this limit.
Export this new limit through sysfs and check these limits in bio_full().
Also when a LLDD can't dispatch a request to a specific zone, it
will return BLK_STS_ZONE_RESOURCE indicating this request needs to
be delayed, e.g. because the zone it will be dispatched to is still
write-locked. If this happens set the request aside in a local list
to continue trying dispatching requests such as READ requests or a
WRITE/ZONE_APPEND requests targetting other zones. This way we can
still keep a high queue depth without starving other requests even if
one request can't be served due to zone write-locking.
Finally, make sure that the bio sector position indicates the actual
write position as indicated by the device on completion.
Signed-off-by: Keith Busch <kbusch@kernel.org>
[ jth: added zone-append specific add_page and merge_page helpers ]
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
delete_partition() clears the cached last_lookup partition. However the
.last_lookup cache may be overwritten by one IO path after it is cleared
from delete_partition(). Then another IO path may use the cached deleting
partition after hd_struct_free() is called, then use-after-free is triggered
on the cached partition.
Fixes the issue by the following approach:
1) always get the partition's refcount via hd_struct_try_get() before
setting .last_lookup
2) move clearing .last_lookup from delete_partition() to hd_struct_free()
which is the release handle of the partition's percpu-refcount, so that no
IO path can cache deleteing partition via .last_lookup.
It is one candidate approach of Yufen's patch[1] which adds overhead
in fast path by indirect lookup which may introduce one extra cacheline
in IO path. Also this patch relies on percpu-refcount's protection, and
it is easier to understand and verify.
[1] https://lore.kernel.org/linux-block/20200109013551.GB9655@ming.t460p/T/#t
Reported-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hou Tao <houtao1@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The name is only printed for a not registered bdi in writeback. Use the
device name there as is more useful anyway for the unlike case that the
warning triggers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge the _node vs normal version and drop the superflous gfp_t argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a little helper that passes the right nowait flag to blk_queue_enter
based on the bio flag, and terminates the bio with the right error code
if entering the queue fails.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Instead of a convoluted chain just check for REQ_OP_READ directly,
and keep all the memory stall code together in a single unlikely
branch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The current documentation is a little weird, as it doesn't clearly
explain which function to use, and also has the guts of the information
on generic_make_request, which is the internal interface for stacking
drivers.
Fix this up by properly documenting submit_bio, and only documenting
the differences and the use case for generic_make_request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Call blk_mq_make_request when no ->make_request_fn is set. This is
safe now that blk_alloc_queue always sets up the pointer for make_request
based drivers. This avoids an indirect call in the blk-mq driver I/O
fast path, which is rather expensive due to spectre mitigations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
create_io_context just has a single caller, which also happens to not
even use the return value. Just open code it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are only two callers of blk_rq_map_sg/__blk_rq_map_sg that set
the dma_pad value in the queue. Move the handling into those callers
instead of burdening the common code, and move the ->extra_len field
from struct request to struct scsi_cmnd.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
