When a disk has been marked dead, don't print warnings for I/O errors
as they are very much expected.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220323163815.1526998-1-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

kernel ulong and compat_ulong_t may not be same width. Use type directly
to eliminate mismatches.

This would result in truncation rather than EFBIG for 32bit mode for
large disks.
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NKhazhismel Kumykov <khazhy@google.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220414224056.2875681-1-khazhy@google.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Unit of bio->bi_iter.bi_size is bytes, but unit of offset/size
is sector.

Fix the above issue in checking offset/size in bio_trim().

Fixes: e83502ca ("block: fix argument type of bio_trim()")
Cc: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220414084443.1736850-1-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

cppcheck returns this warning
[block/blk-wbt.h:104] -> [block/blk-wbt.c:592]:
  (warning) Function 'wbt_track' argument order different:
  declaration 'rq, flags, ' definition 'rqos, rq, bio'

In commit c1c80384 ("block: remove external dependency on wbt_flags")
wbt_track was removed for the real declaration, its stub should
have been as well.
Signed-off-by: NTom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20220331185458.3427454-1-trix@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: NJakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220331091218.641532-1-jakobkoschel@gmail.com
[axboe: move lookup to where return value is checked]
Signed-off-by: NJens Axboe <axboe@kernel.dk>

ida_alloc_range(..., min, max, ...) returns values from min to max,
inclusive.

So, NR_EXT_DEVT is a valid idx returned by blk_alloc_ext_minor().

This is an issue because in device_add_disk(), this value is used in:
   ddev->devt = MKDEV(disk->major, disk->first_minor);
and NR_EXT_DEVT is '(1 << MINORBITS)'.

So, should 'disk->first_minor' be NR_EXT_DEVT, it would overflow.

Fixes: 22ae8ce8 ("block: simplify bdev/disk lookup in blkdev_get")
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: NJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/cc17199798312406b90834e433d2cefe8266823d.1648306232.git.christophe.jaillet@wanadoo.frSigned-off-by: NJens Axboe <axboe@kernel.dk>

PF_EXITING tasks were silently ignored before the below commits.
Continue doing so. Otherwise python-psutil tests fail:
  ERROR: psutil.tests.test_process.TestProcess.test_zombie_process
  ----------------------------------------------------------------------
  Traceback (most recent call last):
    File "/home/abuild/rpmbuild/BUILD/psutil-5.9.0/build/lib.linux-x86_64-3.9/psutil/_pslinux.py", line 1661, in wrapper
      return fun(self, *args, **kwargs)
    File "/home/abuild/rpmbuild/BUILD/psutil-5.9.0/build/lib.linux-x86_64-3.9/psutil/_pslinux.py", line 2133, in ionice_set
      return cext.proc_ioprio_set(self.pid, ioclass, value)
  ProcessLookupError: [Errno 3] No such process

  During handling of the above exception, another exception occurred:

  Traceback (most recent call last):
    File "/home/abuild/rpmbuild/BUILD/psutil-5.9.0/psutil/tests/test_process.py", line 1313, in test_zombie_process
      succeed_or_zombie_p_exc(fun)
    File "/home/abuild/rpmbuild/BUILD/psutil-5.9.0/psutil/tests/test_process.py", line 1288, in succeed_or_zombie_p_exc
      return fun()
    File "/home/abuild/rpmbuild/BUILD/psutil-5.9.0/build/lib.linux-x86_64-3.9/psutil/__init__.py", line 792, in ionice
      return self._proc.ionice_set(ioclass, value)
    File "/home/abuild/rpmbuild/BUILD/psutil-5.9.0/build/lib.linux-x86_64-3.9/psutil/_pslinux.py", line 1665, in wrapper
      raise NoSuchProcess(self.pid, self._name)
  psutil.NoSuchProcess: process no longer exists (pid=2057)

Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Fixes: 5fc11eeb (block: open code create_task_io_context in set_task_ioprio)
Fixes: a957b612 (block: fix error in handling dead task for ioprio setting)
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Reviewed-by: NJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220328085928.7899-1-jslaby@suse.czSigned-off-by: NJens Axboe <axboe@kernel.dk>

blkg_free() can currently be called in atomic context, either spin lock is
held, or run in rcu callback. Meantime either request queue's release
handler or ->pd_free_fn can sleep.

Fix the issue by scheduling a work function for freeing blkcg_gq the
instance.

[  148.553894] BUG: sleeping function called from invalid context at block/blk-sysfs.c:767
[  148.557381] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/13
[  148.560741] preempt_count: 101, expected: 0
[  148.562577] RCU nest depth: 0, expected: 0
[  148.564379] 1 lock held by swapper/13/0:
[  148.566127]  #0: ffffffff82615f80 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x0/0x1b
[  148.569640] Preemption disabled at:
[  148.569642] [<ffffffff8123f9c3>] ___slab_alloc+0x554/0x661
[  148.573559] CPU: 13 PID: 0 Comm: swapper/13 Kdump: loaded Not tainted 5.17.0_up+ #110
[  148.576834] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-1.fc33 04/01/2014
[  148.579768] Call Trace:
[  148.580567]  <IRQ>
[  148.581262]  dump_stack_lvl+0x56/0x7c
[  148.582367]  ? ___slab_alloc+0x554/0x661
[  148.583526]  __might_resched+0x1af/0x1c8
[  148.584678]  blk_release_queue+0x24/0x109
[  148.585861]  kobject_cleanup+0xc9/0xfe
[  148.586979]  blkg_free+0x46/0x63
[  148.587962]  rcu_do_batch+0x1c5/0x3db
[  148.589057]  rcu_core+0x14a/0x184
[  148.590065]  __do_softirq+0x14d/0x2c7
[  148.591167]  __irq_exit_rcu+0x7a/0xd4
[  148.592264]  sysvec_apic_timer_interrupt+0x82/0xa5
[  148.593649]  </IRQ>
[  148.594354]  <TASK>
[  148.595058]  asm_sysvec_apic_timer_interrupt+0x12/0x20

Cc: Tejun Heo <tj@kernel.org>
Fixes: 0a9a25ca ("block: let blkcg_gq grab request queue's refcnt")
Reported-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/linux-block/20220322093322.GA27283@lst.de/Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220323011308.2010380-1-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

The inode allocation is supposed to use alloc_inode_sb(), so convert
kmem_cache_alloc() of all filesystems to alloc_inode_sb().

Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.comSigned-off-by: NMuchun Song <songmuchun@bytedance.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>		[ext4]
Acked-by: NRoman Gushchin <roman.gushchin@linux.dev>
Cc: Alex Shi <alexs@kernel.org>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Fam Zheng <fam.zheng@bytedance.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kari Argillander <kari.argillander@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

bfq_get_queue() expects a "bool" for the third arg, so pass "false"
rather than "BLK_RW_ASYNC" which will soon be removed.

Link: https://lkml.kernel.org/r/164549983746.9187.7949730109246767909.stgit@noble.brownSigned-off-by: NNeilBrown <neilb@suse.de>
Acked-by: NJens Axboe <axboe@kernel.dk>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Throttled bios can't be issued after del_gendisk() is done, thus
it's better to cancel them immediately rather than waiting for
throttle is done.

For example, if user thread is throttled with low bps while it's
issuing large io, and the device is deleted. The user thread will
wait for a long time for io to return.
Signed-off-by: NYu Kuai <yukuai3@huawei.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220318130144.1066064-4-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

In the whole lifetime of blkcg_gq instance, ->q will be referred, such
as, ->pd_free_fn() is called in blkg_free, and throtl_pd_free() still
may touch the request queue via &tg->service_queue.pending_timer which
is handled by throtl_pending_timer_fn(), so it is reasonable to grab
request queue's refcnt by blkcg_gq instance.

Previously blkcg_exit_queue() is called from blk_release_queue, and it
is hard to avoid the use-after-free. But recently commit 1059699f ("block:
move blkcg initialization/destroy into disk allocation/release handler")
is merged to for-5.18/block, it becomes simple to fix the issue by simply
grabbing request queue's refcnt.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220318130144.1066064-3-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

In throtl_pending_timer_fn(), request queue is retrieved from throttle
data. And tg's pending timer is deleted synchronously when releasing the
associated blkg, at that time, throttle data may have been freed since
commit 1059699f ("block: move blkcg initialization/destroy into disk
allocation/release handler") moves freeing q->td to disk_release() from
blk_release_queue(). So use-after-free on q->td in throtl_pending_timer_fn
can be triggered.

Fixes the issue by:

- do nothing in case that disk is released, when there isn't any bio to
  dispatch

- retrieve request queue from blkg instead of throttle data for
non top-level pending timer.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220318130144.1066064-2-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

When IO requests are made continuously and the target block device
handles requests faster than request arrival, the request dispatch loop
keeps on repeating to dispatch the arriving requests very long time,
more than a minute. Since the loop runs as a workqueue worker task, the
very long loop duration triggers workqueue watchdog timeout and BUG [1].

To avoid the very long loop duration, break the loop periodically. When
opportunity to dispatch requests still exists, check need_resched(). If
need_resched() returns true, the dispatch loop already consumed its time
slice, then reschedule the dispatch work and break the loop. With heavy
IO load, need_resched() does not return true for 20~30 seconds. To cover
such case, check time spent in the dispatch loop with jiffies. If more
than 1 second is spent, reschedule the dispatch work and break the loop.

[1]

[  609.691437] BUG: workqueue lockup - pool cpus=10 node=1 flags=0x0 nice=-20 stuck for 35s!
[  609.701820] Showing busy workqueues and worker pools:
[  609.707915] workqueue events: flags=0x0
[  609.712615]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2
[  609.712626]     pending: drm_fb_helper_damage_work [drm_kms_helper]
[  609.712687] workqueue events_freezable: flags=0x4
[  609.732943]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2
[  609.732952]     pending: pci_pme_list_scan
[  609.732968] workqueue events_power_efficient: flags=0x80
[  609.751947]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2
[  609.751955]     pending: neigh_managed_work
[  609.752018] workqueue kblockd: flags=0x18
[  609.769480]   pwq 21: cpus=10 node=1 flags=0x0 nice=-20 active=3/256 refcnt=4
[  609.769488]     in-flight: 1020:blk_mq_run_work_fn
[  609.769498]     pending: blk_mq_timeout_work, blk_mq_run_work_fn
[  609.769744] pool 21: cpus=10 node=1 flags=0x0 nice=-20 hung=35s workers=2 idle: 67
[  639.899730] BUG: workqueue lockup - pool cpus=10 node=1 flags=0x0 nice=-20 stuck for 66s!
[  639.909513] Showing busy workqueues and worker pools:
[  639.915404] workqueue events: flags=0x0
[  639.920197]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2
[  639.920215]     pending: drm_fb_helper_damage_work [drm_kms_helper]
[  639.920365] workqueue kblockd: flags=0x18
[  639.939932]   pwq 21: cpus=10 node=1 flags=0x0 nice=-20 active=3/256 refcnt=4
[  639.939942]     in-flight: 1020:blk_mq_run_work_fn
[  639.939955]     pending: blk_mq_timeout_work, blk_mq_run_work_fn
[  639.940212] pool 21: cpus=10 node=1 flags=0x0 nice=-20 hung=66s workers=2 idle: 67

Fixes: 6e6fcbc2 ("blk-mq: support batching dispatch in case of io")
Signed-off-by: NShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.10+
Link: https://lore.kernel.org/linux-block/20220310091649.zypaem5lkyfadymg@shindev/
Link: https://lore.kernel.org/r/20220318022641.133484-1-shinichiro.kawasaki@wdc.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Convert all callers; mostly this is just changing the aops to point
at it, but a few implementations need a little more work.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: NDamien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: NDamien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs

There is a spelling mistake in a bfq_log_bfqq message. Fix it.
Signed-off-by: NColin Ian King <colin.i.king@gmail.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220315221539.2959167-1-colin.i.king@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Remove special-casing of a NULL invalidatepage, since there is no
more block_invalidatepage.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: NDamien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: NDamien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs

blk-iocost and iolatency are cgroup aware rq-qos policies but they didn't
disable merges across different cgroups. This obviously can lead to
accounting and control errors but more importantly to priority inversions -
e.g. an IO which belongs to a higher priority cgroup or IO class may end up
getting throttled incorrectly because it gets merged to an IO issued from a
low priority cgroup.

Fix it by adding blk_cgroup_mergeable() which is called from merge paths and
rejects cross-cgroup and cross-issue_as_root merges.
Signed-off-by: NTejun Heo <tj@kernel.org>
Fixes: d7067512 ("block: introduce blk-iolatency io controller")
Cc: stable@vger.kernel.org # v4.19+
Cc: Josef Bacik <jbacik@fb.com>
Link: https://lore.kernel.org/r/Yi/eE/6zFNyWJ+qd@slm.duckdns.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

a647a524 ("block: don't call rq_qos_ops->done_bio if the bio isn't
tracked") made bio_endio() skip rq_qos_done_bio() if BIO_TRACKED is not set.
While this fixed a potential oops, it also broke blk-iocost by skipping the
done_bio callback for merged bios.

Before, whether a bio goes through rq_qos_throttle() or rq_qos_merge(),
rq_qos_done_bio() would be called on the bio on completion with BIO_TRACKED
distinguishing the former from the latter. rq_qos_done_bio() is not called
for bios which wenth through rq_qos_merge(). This royally confuses
blk-iocost as the merged bios never finish and are considered perpetually
in-flight.

One reliably reproducible failure mode is an intermediate cgroup geting
stuck active preventing its children from being activated due to the
leaf-only rule, leading to loss of control. The following is from
resctl-bench protection scenario which emulates isolating a web server like
workload from a memory bomb run on an iocost configuration which should
yield a reasonable level of protection.

  # cat /sys/block/nvme2n1/device/model
  Samsung SSD 970 PRO 512GB
  # cat /sys/fs/cgroup/io.cost.model
  259:0 ctrl=user model=linear rbps=834913556 rseqiops=93622 rrandiops=102913 wbps=618985353 wseqiops=72325 wrandiops=71025
  # cat /sys/fs/cgroup/io.cost.qos
  259:0 enable=1 ctrl=user rpct=95.00 rlat=18776 wpct=95.00 wlat=8897 min=60.00 max=100.00
  # resctl-bench -m 29.6G -r out.json run protection::scenario=mem-hog,loops=1
  ...
  Memory Hog Summary
  ==================

  IO Latency: R p50=242u:336u/2.5m p90=794u:1.4m/7.5m p99=2.7m:8.0m/62.5m max=8.0m:36.4m/350m
              W p50=221u:323u/1.5m p90=709u:1.2m/5.5m p99=1.5m:2.5m/9.5m max=6.9m:35.9m/350m

  Isolation and Request Latency Impact Distributions:

                min   p01   p05   p10   p25   p50   p75   p90   p95   p99   max  mean stdev
  isol%       15.90 15.90 15.90 40.05 57.24 59.07 60.01 74.63 74.63 90.35 90.35 58.12 15.82
  lat-imp%        0     0     0     0     0  4.55 14.68 15.54 233.5 548.1 548.1 53.88 143.6

  Result: isol=58.12:15.82% lat_imp=53.88%:143.6 work_csv=100.0% missing=3.96%

The isolation result of 58.12% is close to what this device would show
without any IO control.

Fix it by introducing a new flag BIO_QOS_MERGED to mark merged bios and
calling rq_qos_done_bio() on them too. For consistency and clarity, rename
BIO_TRACKED to BIO_QOS_THROTTLED. The flag checks are moved into
rq_qos_done_bio() so that it's next to the code paths that set the flags.

With the patch applied, the above same benchmark shows:

  # resctl-bench -m 29.6G -r out.json run protection::scenario=mem-hog,loops=1
  ...
  Memory Hog Summary
  ==================

  IO Latency: R p50=123u:84.4u/985u p90=322u:256u/2.5m p99=1.6m:1.4m/9.5m max=11.1m:36.0m/350m
              W p50=429u:274u/995u p90=1.7m:1.3m/4.5m p99=3.4m:2.7m/11.5m max=7.9m:5.9m/26.5m

  Isolation and Request Latency Impact Distributions:

                min   p01   p05   p10   p25   p50   p75   p90   p95   p99   max  mean stdev
  isol%       84.91 84.91 89.51 90.73 92.31 94.49 96.36 98.04 98.71 100.0 100.0 94.42  2.81
  lat-imp%        0     0     0     0     0  2.81  5.73 11.11 13.92 17.53 22.61  4.10  4.68

  Result: isol=94.42:2.81% lat_imp=4.10%:4.68 work_csv=58.34% missing=0%
Signed-off-by: NTejun Heo <tj@kernel.org>
Fixes: a647a524 ("block: don't call rq_qos_ops->done_bio if the bio isn't tracked")
Cc: stable@vger.kernel.org # v5.15+
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/Yi7rdrzQEHjJLGKB@slm.duckdns.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

blkcg_init_queue() may add rq qos structures to request queue, previously
blk_cleanup_queue() calls rq_qos_exit() to release them, but commit
8e141f9e ("block: drain file system I/O on del_gendisk")
moves rq_qos_exit() into del_gendisk(), so memory leak is caused
because queues may not have disk, such as un-present scsi luns, nvme
admin queue, ...

Fixes the issue by adding rq_qos_exit() to blk_cleanup_queue() back.

BTW, v5.18 won't need this patch any more since we move
blkcg_init_queue()/blkcg_exit_queue() into disk allocation/release
handler, and patches have been in for-5.18/block.

Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Fixes: 8e141f9e ("block: drain file system I/O on del_gendisk")
Reported-by: syzbot+b42749a851a47a0f581b@syzkaller.appspotmail.com
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220314043018.177141-1-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

We used to sort the plug list if we had multiple queues before dispatching
requests to the IO scheduler. This usually isn't needed, but for certain
workloads that interleave requests to disks, it's a less efficient to
process the plug list one-by-one if everything is interleaved.

Don't sort the list, but skip through it and flush out entries that have
the same target at the same time.

Fixes: df87eb0f ("block: get rid of plug list sorting")
Reported-and-tested-by: NSong Liu <song@kernel.org>
Reviewed-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Song reports that a RAID rebuild workload runs much slower recently,
and it is seeing a lot less merging than it did previously. The reason
is that a previous commit reduced the amount of work we do for plug
merging. RAID rebuild interleaves requests between disks, so a last-entry
check in plug merging always misses a merge opportunity since we always
find a different disk than what we are looking for.

Modify the logic such that it's still a one-hit cache, but ensure that
we check enough to find the right target before giving up.

Fixes: d38a9c04 ("block: only check previous entry for plug merge attempt")
Reported-and-tested-by: NSong Liu <song@kernel.org>
Reviewed-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h.
While doing that rename tracehook_notify_resume to resume_user_mode_work.

Update all of the places that included tracehook.h for these functions to
include resume_user_mode.h instead.

Update all of the callers of tracehook_notify_resume to call
resume_user_mode_work.
Reviewed-by: NKees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.comSigned-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Prepare for supporting IO polling for bio-based driver.

Add ->poll_bio callback so that bio-based driver can provide their own
logic for polling bio.

Also fix ->submit_bio_bio typo in comment block above
__submit_bio_noacct.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

Keep all teardown of file system I/O related functionality in one place.
There can't be file system I/O in disk_release(), so it is safe to move
rq_qos_exit() there.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220308055200.735835-15-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Move the calls to ioc_clear_queue and blk_mq_sched_free_rqs into
elevator_exit.  Except for one call where we know we can't have io_cq
structures yet these always go together, and that extra call in an
error path is harmless.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220308055200.735835-14-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

There can't be file system I/O in disk_release(), so move the call to
blk_exit_queue() there, preparing to have the teardown of file system I/O
only functionality in one place, when the gendisk that is needed for it
is torn down.

We still need to freeze queue here since the request is freed after the
bio is completed and passthrough request rely on scheduler tags as well.

The disk can be released before or after queue is cleaned up, and we have
to free the scheduler request pool before blk_cleanup_queue returns,
while the static request pool has to be freed before exiting the
I/O scheduler.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
[hch: rebased, updated the commit log]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220308055200.735835-13-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

After blk_cleanup_queue() returns, disk may not be released yet, so
probably bio may still be submitted and ->q_usage_counter may be
touched, so far this way seems safe, but not good from API's viewpoint.

Move the release q_usage_counter into blk_queue_release().
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220308055200.735835-12-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

The queue's top debugfs dir is removed from blk_release_queue(), so all
hctx's debugfs dirs are removed from there. Given blk_mq_exit_queue()
is only called from blk_cleanup_queue(), it isn't necessary to remove
hctx debugfs from blk_mq_exit_queue().

So remove it from blk_mq_exit_queue().
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220308055200.735835-11-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

blkcg works on FS bio level, so it is reasonable to make both blkcg and
gendisk sharing same lifetime. Meantime there won't be any FS IO when
releasing disk, so safe to move blkcg initialization/destroy into disk
allocation/release handler

Long term, we can move blkcg into gendisk completely.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220308055200.735835-10-hch@lst.de
[axboe: fixup missing blk-cgroup.h include]
Signed-off-by: NJens Axboe <axboe@kernel.dk>

To simplify further changes allow for double calling blk_mq_free_rqs on
a queue.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
[hch: split out from a larger patch]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220308055200.735835-3-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

I/O accounting buckets I/O into the read/write/discard categories into
which passthrough I/O does not fit at all.  It also accounts to the
block_device, which may not even exist for passthrough I/O.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220308055200.735835-2-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

First code becomes more clean by switching to xarray from plain array.

Second use-after-free on q->queue_hw_ctx can be fixed because
queue_for_each_hw_ctx() may be run when updating nr_hw_queues is
in-progress. With this patch, q->hctx_table is defined as xarray, and
this structure will share same lifetime with request queue, so
queue_for_each_hw_ctx() can use q->hctx_table to lookup hctx reliably.
Reported-by: NYu Kuai <yukuai3@huawei.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220308073219.91173-7-ming.lei@redhat.com
[axboe: fix blk_mq_hw_ctx forward declaration]
Signed-off-by: NJens Axboe <axboe@kernel.dk>

It is inevitable to cause use-after-free on q->queue_hw_ctx between
queue_for_each_hw_ctx() and blk_mq_update_nr_hw_queues(). And converting
to xarray can fix the uaf, meantime code gets cleaner.

Prepare for converting q->queue_hctx_ctx into xarray, one thing is that
xa_for_each() can only accept 'unsigned long' as index, so changes type
of hctx index of queue_for_each_hw_ctx() into 'unsigned long'.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220308073219.91173-6-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

queue map can be changed when updating nr_hw_queues, so we need to
reconfigure queue's poll capability. Add one helper for doing this job.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220308073219.91173-4-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

blk_mq_alloc_and_init_hctx() has already taken reuse into account, so
no need to do it outside, then we can simplify blk_mq_realloc_hw_ctxs().
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220308073219.91173-3-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

The current code always uses default queue map and hw queue index
for figuring out the numa node for hw queue, this way isn't correct
because blk-mq supports three queue maps, and the correct queue map
should be used for the specified hw queue.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220308073219.91173-2-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

A crash [1] happened to be triggered in conjunction with commit
2d52c58b ("block, bfq: honor already-setup queue merges"). The
latter was then reverted by commit ebc69e89 ("Revert "block, bfq:
honor already-setup queue merges""). Yet, the reverted commit was not
the one introducing the bug. In fact, it actually triggered a UAF
introduced by a different commit, and now fixed by commit d29bd414
("block, bfq: reset last_bfqq_created on group change").

So, there is no point in keeping commit 2d52c58b ("block, bfq:
honor already-setup queue merges") out. This commit restores it.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=214503Reported-by: NHolger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: NPaolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20211125181510.15004-1-paolo.valente@linaro.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

Commit 9d497e29 ("block: don't protect submit_bio_checks by
q_usage_counter") moved blk_mq_attempt_bio_merge and rq_qos_throttle
calls out of q_usage_counter protection. However, these functions require
q_usage_counter protection. The blk_mq_attempt_bio_merge call without
the protection resulted in blktests block/005 failure with KASAN null-
ptr-deref or use-after-free at bio merge. The rq_qos_throttle call
without the protection caused kernel hang at qos throttle.

To fix the failures, move the blk_mq_attempt_bio_merge and
rq_qos_throttle calls back to q_usage_counter protection.

Fixes: 9d497e29 ("block: don't protect submit_bio_checks by q_usage_counter")
Signed-off-by: NShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/20220308080915.3473689-1-shinichiro.kawasaki@wdc.comReviewed-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The NVMe specification defines new data integrity formats beyond the
t10 tuple. Add support for the specification defined CRC64 formats,
assuming the reference tag does not need to be split with the "storage
tag".

Cc: Hannes Reinecke <hare@suse.de>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220303201312.3255347-8-kbusch@kernel.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>