Use only one hyphen in kernel-doc notation between the function name
and its short description.
The is the documented kerenl-doc format. It also fixes the HTML
presentation to be consistent with other functions.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Link: https://lore.kernel.org/r/20221201070331.25685-1-rdunlap@infradead.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no iocg_pd_init function. The pd_alloc_fn function pointer of
iocost policy is set with ioc_pd_init. Just correct it.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-6-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we trace vtime_base_rate instead of vtime_rate, there is nowhere
which accesses now->vrate except function ioc_now using now->vrate locally.
Just remove it.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-5-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since commit ac33e91e2d ("blk-iocost: implement vtime loss
compensation") rename original vtime_rate to vtime_base_rate
and current vtime_rate is original vtime_rate with compensation.
The current rate showed in tracepoint is mixed with vtime_rate
and vtime_base_rate:
1) In function ioc_adjust_base_vrate, the first trace_iocost_ioc_vrate_adj
shows vtime_rate, the second trace_iocost_ioc_vrate_adj shows
vtime_base_rate.
2) In function iocg_activate shows vtime_rate by calling
TRACE_IOCG_PATH(iocg_activate...
3) In function ioc_check_iocgs shows vtime_rate by calling
TRACE_IOCG_PATH(iocg_idle...
Trace vtime_base_rate instead of vtime_rate as:
1) Before commit ac33e91e2d ("blk-iocost: implement vtime loss
compensation"), the traced rate is without compensation, so still
show rate without compensation.
2) The vtime_base_rate is more stable while vtime_rate heavily depends on
excess budeget on current period which may change abruptly in next period.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-4-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since commit ac33e91e2daca("blk-iocost: implement vtime loss compensation")
split vtime_rate into vtime_rate and vtime_base_rate, we need reset both
vtime_base_rate and vtime_rate when device parameters are refreshed.
If vtime_base_rate is no reset here, vtime_rate will be overwritten with
old vtime_base_rate soon in ioc_refresh_vrate.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-3-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since commit 10c70d95c0 ("block: remove the bd_openers checks in
blk_drop_partitions") we allow rereading of partition table although
there are users of the block device. This has an undesirable consequence
that e.g. if sda and sdb are assembled to a RAID1 device md0 with
partitions, BLKRRPART ioctl on sda will rescan partition table and
create sda1 device. This partition device under a raid device confuses
some programs (such as libstorage-ng used for initial partitioning for
distribution installation) leading to failures.
Fix the problem refusing to rescan partitions if there is another user
that has the block device exclusively open.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20221130135344.2ul4cyfstfs3znxg@quack3
Fixes: 10c70d95c0 ("block: remove the bd_openers checks in blk_drop_partitions")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221130175653.24299-1-jack@suse.cz
[axboe: fold in followup fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ida_simple[get|remove] are deprecated, and are just wrappers to
ida_[alloc_range|free]. Replace ida_simple[get|remove] with their
corresponding counterparts.
No functional changes.
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://lore.kernel.org/r/20221130123001.25473-1-p.raghav@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We can't just say that the last reference release may block, as any
reference dropped could be the last one. So move the might_sleep() from
blk_free_queue to blk_put_queue and update the documentation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The kobject embedded into the request_queue is used for the queue
directory in sysfs, but that is a child of the gendisks directory and is
intimately tied to it. Move this kobject to the gendisk and use a
refcount_t in the request_queue for the actual request_queue refcounting
that is completely unrelated to the device model.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_register_queue fails to handle errors from blk_mq_sysfs_register,
leaks various resources on errors and accidentally sets queue refs percpu
refcount to percpu mode on kobject_add failure. Fix all that by
properly unwinding on errors.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Split the debugfs removal from blk_unregister_queue into a helper so that
the it can be reused for blk_register_queue error handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Prepare for changes to the block layer sysfs handling by passing the
readily available gendisk to blk_crypto_sysfs_{,un}register.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042637.1009333-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- support some passthrough commands without CAP_SYS_ADMIN
(Kanchan Joshi)
- refactor PCIe probing and reset (Christoph Hellwig)
- various fabrics authentication fixes and improvements (Sagi Grimberg)
- avoid fallback to sequential scan due to transient issues
(Uday Shankar)
- implement support for the DEAC bit in Write Zeroes (Christoph Hellwig)
- allow overriding the IEEE OUI and firmware revision in configfs for
nvmet (Aleksandr Miloserdov)
- force reconnect when number of queue changes in nvmet (Daniel Wagner)
- minor fixes and improvements (Uros Bizjak, Joel Granados,
Sagi Grimberg, Christoph Hellwig, Christophe JAILLET)
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Merge tag 'nvme-6.2-2022-11-29' of git://git.infradead.org/nvme into for-6.2/block
Pull NVMe updates from Christoph:
"nvme updates for Linux 6.2
- support some passthrough commands without CAP_SYS_ADMIN
(Kanchan Joshi)
- refactor PCIe probing and reset (Christoph Hellwig)
- various fabrics authentication fixes and improvements (Sagi Grimberg)
- avoid fallback to sequential scan due to transient issues
(Uday Shankar)
- implement support for the DEAC bit in Write Zeroes (Christoph Hellwig)
- allow overriding the IEEE OUI and firmware revision in configfs for
nvmet (Aleksandr Miloserdov)
- force reconnect when number of queue changes in nvmet (Daniel Wagner)
- minor fixes and improvements (Uros Bizjak, Joel Granados,
Sagi Grimberg, Christoph Hellwig, Christophe JAILLET)"
* tag 'nvme-6.2-2022-11-29' of git://git.infradead.org/nvme: (45 commits)
nvmet: expose firmware revision to configfs
nvmet: expose IEEE OUI to configfs
nvme: rename the queue quiescing helpers
nvmet: fix a memory leak in nvmet_auth_set_key
nvme: return err on nvme_init_non_mdts_limits fail
nvme: avoid fallback to sequential scan due to transient issues
nvme-rdma: stop auth work after tearing down queues in error recovery
nvme-tcp: stop auth work after tearing down queues in error recovery
nvme-auth: have dhchap_auth_work wait for queues auth to complete
nvme-auth: remove redundant auth_work flush
nvme-auth: convert dhchap_auth_list to an array
nvme-auth: check chap ctrl_key once constructed
nvme-auth: no need to reset chap contexts on re-authentication
nvme-auth: remove redundant deallocations
nvme-auth: clear sensitive info right after authentication completes
nvme-auth: guarantee dhchap buffers under memory pressure
nvme-auth: don't keep long lived 4k dhchap buffer
nvme-auth: remove redundant if statement
nvme-auth: don't override ctrl keys before validation
nvme-auth: don't ignore key generation failures when initializing ctrl keys
...
Rename deadline_is_seq_writes() to deadline_is_seq_write() (remove the
"s" plural) to more correctly reflect the fact that this function tests
a single request, not multiple requests.
Fixes: 015d02f485 ("block: mq-deadline: Do not break sequential write streams to zoned HDDs")
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20221126025550.967914-2-damien.lemoal@opensource.wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A submitter workqueue is dynamically allocated by init_submitter()
called by drbd_create_device(), we should destroy it when this
device is not needed or destroyed.
Fixes: 113fef9e20 ("drbd: prepare to queue write requests on a submit worker")
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Link: https://lore.kernel.org/r/20221124015817.2729789-3-bobo.shaobowang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This revert c2258ffc56 ("drbd: poison free'd device, resource and
connection structs"), add memset is odd here for debugging, there are
some methods to accurately show what happened, such as kdump.
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Link: https://lore.kernel.org/r/20221124015817.2729789-2-bobo.shaobowang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
mq-deadline ensures an in order dispatching of write requests to zoned
block devices using a per zone lock (a bit). This implies that for any
purely sequential write workload, the drive is exercised most of the
time at a maximum queue depth of one.
However, when such sequential write workload crosses a zone boundary
(when sequentially writing multiple contiguous zones), zone write
locking may prevent the last write to one zone to be issued (as the
previous write is still being executed) but allow the first write to the
following zone to be issued (as that zone is not yet being writen and
not locked). This result in an out of order delivery of the sequential
write commands to the device every time a zone boundary is crossed.
While such behavior does not break the sequential write constraint of
zoned block devices (and does not generate any write error), some zoned
hard-disks react badly to seeing these out of order writes, resulting in
lower write throughput.
This problem can be addressed by always dispatching the first request
of a stream of sequential write requests, regardless of the zones
targeted by these sequential writes. To do so, the function
deadline_skip_seq_writes() is introduced and used in
deadline_next_request() to select the next write command to issue if the
target device is an HDD (blk_queue_nonrot() being false).
deadline_fifo_request() is modified using the new
deadline_earlier_request() and deadline_is_seq_write() helpers to ignore
requests in the fifo list that have a preceding request in lba order
that is sequential.
With this fix, a sequential write workload executed with the following
fio command:
fio --name=seq-write --filename=/dev/sda --zonemode=zbd --direct=1 \
--size=68719476736 --ioengine=libaio --iodepth=32 --rw=write \
--bs=65536
results in an increase from 225 MB/s to 250 MB/s of the write throughput
of an SMR HDD (11% increase).
Cc: <stable@vger.kernel.org>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20221124021208.242541-3-damien.lemoal@opensource.wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
dd_finish_request() tests if the per prio fifo_list is not empty to
determine if request dispatching must be restarted for handling blocked
write requests to zoned devices with a call to
blk_mq_sched_mark_restart_hctx(). While simple, this implementation has
2 problems:
1) Only the priority level of the completed request is considered.
However, writes to a zone may be blocked due to other writes to the
same zone using a different priority level. While this is unlikely to
happen in practice, as writing a zone with different IO priorirites
does not make sense, nothing in the code prevents this from
happening.
2) The use of list_empty() is dangerous as dd_finish_request() does not
take dd->lock and may run concurrently with the insert and dispatch
code.
Fix these 2 problems by testing the write fifo list of all priority
levels using the new helper dd_has_write_work(), and by testing each
fifo list using list_empty_careful().
Fixes: c807ab520f ("block/mq-deadline: Add I/O priority support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20221124021208.242541-2-damien.lemoal@opensource.wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allow the compiler to verify consistency of function declarations and
function definitions. This patch fixes the following sparse errors:
block/blk-crypto-profile.c:241:14: error: no previous prototype for ‘blk_crypto_get_keyslot’ [-Werror=missing-prototypes]
241 | blk_status_t blk_crypto_get_keyslot(struct blk_crypto_profile *profile,
| ^~~~~~~~~~~~~~~~~~~~~~
block/blk-crypto-profile.c:318:6: error: no previous prototype for ‘blk_crypto_put_keyslot’ [-Werror=missing-prototypes]
318 | void blk_crypto_put_keyslot(struct blk_crypto_keyslot *slot)
| ^~~~~~~~~~~~~~~~~~~~~~
block/blk-crypto-profile.c:344:6: error: no previous prototype for ‘__blk_crypto_cfg_supported’ [-Werror=missing-prototypes]
344 | bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
block/blk-crypto-profile.c:373:5: error: no previous prototype for ‘__blk_crypto_evict_key’ [-Werror=missing-prototypes]
373 | int __blk_crypto_evict_key(struct blk_crypto_profile *profile,
| ^~~~~~~~~~~~~~~~~~~~~~
Cc: Eric Biggers <ebiggers@google.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221123172923.434339-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
DRBD currently has a mix of GPL-2.0 and GPL-2.0-or-later SPDX license
identifiers. We have decided to stick with GPL 2.0 only, so consistently
use that identifier.
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20221122134301.69258-5-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Or, depending on the way locking is implemented at the call sites,
some updates could be lost (has not been observed).
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20221122134301.69258-2-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The commit ee9d55210c ("blk-mq: simplify blk_mq_realloc_tag_set_tags")
cleaned up the function blk_mq_realloc_tag_set_tags. After this change,
the function does not update nr_hw_queues of struct blk_mq_tag_set when
new nr_hw_queues value is smaller than original. This results in failure
of queue number change of block devices. To avoid the failure, add the
missing nr_hw_queues update.
Fixes: ee9d55210c ("blk-mq: simplify blk_mq_realloc_tag_set_tags")
Reported-by: Chaitanya Kulkarni <chaitanyak@nvidia.com>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/linux-block/20221118140640.featvt3fxktfquwh@shindev/
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221122084917.2034220-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_crypto_get_keyslot, blk_crypto_put_keyslot, __blk_crypto_evict_key
and __blk_crypto_cfg_supported are only used internally by the
blk-crypto code, so move the out of blk-crypto-profile.h, which is
included by drivers that supply blk-crypto functionality.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042944.1009870-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a blk_crypto_config_supported_natively helper that wraps
__blk_crypto_cfg_supported to retrieve the crypto_profile from the
request queue. With this fscrypt can stop including
blk-crypto-profile.h and rely on the public consumer interface in
blk-crypto.h.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042944.1009870-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Switch all public blk-crypto interfaces to use struct block_device
arguments to specify the device they operate on instead of th
request_queue, which is a block layer implementation detail.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042944.1009870-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allow user to set currently active firmware revision
Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
Reviewed-by: Dmitriy Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Aleksandr Miloserdov <a.miloserdov@yadro.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Allow user to set OUI for the controller vendor.
Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
Reviewed-by: Dmitriy Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Aleksandr Miloserdov <a.miloserdov@yadro.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Naming the nvme helpers that wrap the block quiesce functionality
_start/_stop is rather confusing. Switch to using the quiesce naming
used by the block layer instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
As noted by Michal, the blkg_iostat_set's in the lockless list
hold reference to blkg's to protect against their removal. Those
blkg's hold reference to blkcg. When a cgroup is being destroyed,
cgroup_rstat_flush() is only called at css_release_work_fn() which is
called when the blkcg reference count reaches 0. This circular dependency
will prevent blkcg from being freed until some other events cause
cgroup_rstat_flush() to be called to flush out the pending blkcg stats.
To prevent this delayed blkcg removal, add a new cgroup_rstat_css_flush()
function to flush stats for a given css and cpu and call it at the blkgs
destruction path, blkcg_destroy_blkgs(), whenever there are still some
pending stats to be flushed. This will ensure that blkcg reference
count can reach 0 ASAP.
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221105005902.407297-4-longman@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For a system with many CPUs and block devices, the time to do
blkcg_rstat_flush() from cgroup_rstat_flush() can be rather long. It
can be especially problematic as interrupt is disabled during the flush.
It was reported that it might take seconds to complete in some extreme
cases leading to hard lockup messages.
As it is likely that not all the percpu blkg_iostat_set's has been
updated since the last flush, those stale blkg_iostat_set's don't need
to be flushed in this case. This patch optimizes blkcg_rstat_flush()
by keeping a lockless list of recently updated blkg_iostat_set's in a
newly added percpu blkcg->lhead pointer.
The blkg_iostat_set is added to a lockless list on the update side
in blk_cgroup_bio_start(). It is removed from the lockless list when
flushed in blkcg_rstat_flush(). Due to racing, it is possible that
blk_iostat_set's in the lockless list may have no new IO stats to be
flushed, but that is OK.
To protect against destruction of blkg, a percpu reference is gotten
when putting into the lockless list and put back when removed.
When booting up an instrumented test kernel with this patch on a
2-socket 96-thread system with cgroup v2, out of the 2051 calls to
cgroup_rstat_flush() after bootup, 1788 of the calls were exited
immediately because of empty lockless list. After an all-cpu kernel
build, the ratio became 6295424/6340513. That was more than 99%.
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221105005902.407297-3-longman@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For blkcg_css_alloc(), the only error that will be returned is -ENOMEM.
Simplify error handling code by returning this error directly instead
of setting an intermediate "ret" variable.
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221105005902.407297-2-longman@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We hold a reference to the holder kobject for each bd_holder_disk,
so to make the code a bit more robust, use a reference to it instead
of the block_device. As long as no one clears ->bd_holder_dir in
before freeing the disk, this isn't strictly required, but it does
make the code more clear and more robust.
Orignally-From: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221115141054.1051801-10-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, the caller of bd_link_disk_holer() get 'bdev' by
blkdev_get_by_dev(), which will look up 'bdev' by inode number 'dev'.
Howerver, it's possible that del_gendisk() can be called currently, and
'bd_holder_dir' can be freed before bd_link_disk_holer() access it, thus
use after free is triggered.
t1: t2:
bdev = blkdev_get_by_dev
del_gendisk
kobject_put(bd_holder_dir)
kobject_free()
bd_link_disk_holder
Fix the problem by checking disk is still live and grabbing a reference
to 'bd_holder_dir' first in bd_link_disk_holder().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221115141054.1051801-9-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that dm has been fixed to track of holder registrations before
add_disk, the somewhat buggy block layer code can be safely removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20221115141054.1051801-8-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
