Commit f906a6a0 ("blk-mq: improve tag waiting setup for non-shared
tags") mark restart for unshared tags for improvement. At that time,
tags is only shared betweens queues and we can check if tags is shared
by test BLK_MQ_F_TAG_SHARED.
Afterwards, commit 32bc15af ("blk-mq: Facilitate a shared sbitmap per
tagset") enabled tags share betweens hctxs inside a queue. We only
mark restart for shared hctxs inside a queue and may cause io hung if
there is no tag currently allocated by hctxs going to be marked restart.
Wait on sbitmap_queue instead of mark restart for shared hctxs case to
fix this.

Fixes: 32bc15af ("blk-mq: Facilitate a shared sbitmap per tagset")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

For shared queues case, we will only wait on bitmap_tags if we fail to get
driver tag. However, rq could be from breserved_tags, then two problems
will occur:
1. io hung if no tag is currently allocated from bitmap_tags.
2. unnecessary wakeup when tag is freed to bitmap_tags while no tag is
freed to breserved_tags.
Wait on the bitmap which rq from to fix this.

Fixes: f906a6a0 ("blk-mq: improve tag waiting setup for non-shared tags")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Commit 97889f9a ("blk-mq: remove synchronize_rcu() from
blk_mq_del_queue_tag_set()") remove handle of TAG_SHARED in restart,
then shared_hctx_restart counted for how many hardware queues are marked
for restart is removed too.
Remove the stale comment that we still count hardware queues need restart.

Fixes: 97889f9a ("blk-mq: remove synchronize_rcu() from blk_mq_del_queue_tag_set()")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Commit 1f5bd336 ("blk-mq: add blk_mq_alloc_request_hctx") add
blk_mq_alloc_request_hctx to send commands to a specific queue. If
BLK_MQ_REQ_NOWAIT is not set in tag allocation, we may change to different
hctx after sleep and get tag from unexpected hctx. So BLK_MQ_REQ_NOWAIT
must be set in flags for blk_mq_alloc_request_hctx.
After commit 600c3b0c ("blk-mq: open code __blk_mq_alloc_request in
blk_mq_alloc_request_hctx"), blk_mq_alloc_request_hctx return -EINVAL
if both BLK_MQ_REQ_NOWAIT and BLK_MQ_REQ_RESERVED are not set instead of
if BLK_MQ_REQ_NOWAIT is not set. So if BLK_MQ_REQ_NOWAIT is not set and
BLK_MQ_REQ_RESERVED is set, blk_mq_alloc_request_hctx could alloc tag
from unexpected hctx. I guess what we need here is that return -EINVAL
if either BLK_MQ_REQ_NOWAIT or BLK_MQ_REQ_RESERVED is not set.

Currently both BLK_MQ_REQ_NOWAIT and BLK_MQ_REQ_RESERVED will be set if
specific hctx is needed in nvme_auth_submit, nvmf_connect_io_queue
and nvmf_connect_admin_queue. Fix the potential BLK_MQ_REQ_NOWAIT missed
case in future.

Fixes: 600c3b0c ("blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The capability attribute was added in 2017 to expose the kernel internal
GENHD_FL_MEDIA_CHANGE_NOTIFY to userspace without ever adding a value to
an UAPI header, and without ever setting it in any driver until it was
finally removed in Linux 5.7.

Deprecate the file and always return 0 instead of exposing the other
internal and frequently renumbered other gendisk flags.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230203150209.3199115-1-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

new_blkg can be NULL if the caller didn't pass in a pre-allocated blkg.
Don't try to free it in that case.

Fixes: 27b642b0 ("blk-cgroup: simplify blkg freeing from initialization failure paths")
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230206150201.3438972-1-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-24-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-23-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-22-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-21-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230203150634.3199647-20-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-19-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230203150634.3199647-18-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page and bvec_set_folio helpers to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230203150634.3199647-17-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-16-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230203150634.3199647-15-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Link: https://lore.kernel.org/r/20230203150634.3199647-14-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230203150634.3199647-13-hch@lst.deReviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_folio helper to initialize a bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-12-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-11-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_virt helper to initialize the special_vec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-10-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize the copy up bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-9-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_virt helper to initialize the special_vec.
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/20230203150634.3199647-8-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
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/20230203150634.3199647-7-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-6-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Add a helper for setting up the special_bvec instead of open coding it
in three place, and use the new bvec_set_page helper to initialize
special_vec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-5-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

A small wrapper around bvec_set_page for callers that have a virtual
address.
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/20230203150634.3199647-4-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

A smaller wrapper around bvec_set_page that takes a folio instead.
There are only two potential users for this in the tree, but the number
will grow in the future.
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/20230203150634.3199647-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Add a helper to initialize a bvec based of a page pointer.  This will help
removing various open code bvec initializations.
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/20230203150634.3199647-2-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

cgroup information only makes sense on a live gendisk that allows
file system I/O (which includes the raw block device).  So move over
the cgroup related members.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-20-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Pass a gendisk to blkg_lookup and use that to find the match as part
of phasing out usage of the request_queue in the blk-cgroup code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-19-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

No need to the request_queue here, pass a gendisk and extract the
node ids from that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-18-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Prepare for storing the blkcg information in the gendisk instead of
the request_queue.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-17-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

This is what about half of the users already want, and it's only going to
grow more.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-16-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

These op vectors are constant, so mark them const.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-15-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Switch to passing a gendisk, and make rq_qos_add initialize all required
fields and drop the not required q argument from rq_qos_del.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-14-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

These two functions are rather larger and not in a fast path, so move
them out of line.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-13-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

wbt_queue_depth_changed just updates a field and calls another function.
Open code it in wbt_init, so that the local queue variable can be used
instead of the one stored in the rq_qos.  This will allow delaying that
rq_qos->queue assignment in a subsequent patch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-12-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

A large part of blk-wbt.h is only used in blk-wbt.c, so move it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-11-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Pass a gendisk to wbt_init to prepare for phasing out usage of the
request_queue in the blk-cgroup code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-10-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>