skd_main: don't use req->special

Add a retries field to the internal request structure instead, which gets
set to zero on the first submission.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nullb: remove leftover legacy request code

null_softirq_done_fn is only used for the blk-mq path, so remove the
other branch.  Also rename the function to better match the method name.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fnic: fix fnic_scsi_host_{start,end}_tag

The way these functions abuse ->special to try to store the dummy
request looks completely broken, given that it actually stores the
original scsi command.

Instead switch to ->host_scribble and store the actual dummy command.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove set but not used variable 'et'

Fixes gcc '-Wunused-but-set-variable' warning:

block/blk-ioc.c: In function 'put_io_context_active':
block/blk-ioc.c:174:24: warning:
 variable 'et' set but not used [-Wunused-but-set-variable]

It not used any more after commit
a1ce35fa4985 ("block: remove dead elevator code")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove the BLKPREP_* values.

Unused now.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: return blk_status_t from device handler ->prep_fn

Remove the last use of the old BLKPREP_* values, which get converted
to BLK_STS_* later anyway.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: return blk_status_t from scsi_init_io and ->init_command

Replace the old BLKPREP_* values with the BLK_STS_ ones that they are
converted to later anyway.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: clean up error handling in scsi_init_io

There is no need to call scsi_mq_free_sgtables until we have actually
allocated sgtables.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: push blk_status_t up into scsi_setup_{fs,scsi}_cmnd

This just moves the prep_to_mq calls up in preparation of further removal
of BLKPREP_* usage.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: simplify scsi_prep_state_check

Return a blk_status_t directly, and make the code a little more compact
by handling the fast path in the caller.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ide: cleanup ->prep_rq calling convention

The return value is just used as a binary yes/no decision, so switch
it to a bool instead of the old BLKPREP_* values returned as an int.

Also clean up a few related comments.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove req->timeout_list

Unused now that the legacy request path is gone.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xxx: use for_each_sg

Use the proper helper instead of manually iterating the scatterlist,
which is broken in the presence of chained S/G lists.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: don't use req->special

Instead create add to the icmd into struct mtip_cmd which can be unioned
with the scatterlist used for the normal I/O path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: remove mtip_get_int_command

Merging this function into the only callers makes the code flow easier.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: remove mtip_init_cmd_header

There isn't much need for this helper - we can just calculate the offset
for the command header once late in the submission path and fill out
the ctba and ctbau fields there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: add missing endianess annotations on struct smart_attr

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: remove __force_bit2int

There is no good excuse not to use proper __le16/32 types.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: return a blk_status_t from mtip_send_trim

This allows for better error propagation and simpler code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: merge mtip_submit_request into mtip_queue_rq

Factor out a new is_stopped helper that matches the existing
is_se_active helper, and merge the trivial amount of remaining code
into the only caller.  This also allows better error handling by
returning a BLK_STS_* directly instead of explicitly calling
blk_mq_end_request, and moving blk_mq_start_request closer to the
actual issue to hardware.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mtip32xx: move the blk_rq_map_sg call to mtip_hw_submit_io

We have all arguments at hand in mtip_hw_submit_io, so keep the
rq to sg mapping close to the dma_map_sg call.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

sx8: use a per-host tag_set

The current sx8 code spends a lot of effort dealing with the fact that
tags are per-host, but there might be multiple queues.  Now that the
driver has been converted to blk-mq it can take care of the blk-mq
tag_set concept that has been designed just for that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

sx8: cleanup queue and disk allocation / freeing

Make the disk/queue alloc and free helpers per-port by moving the
trivial loops into the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq-tag: document tag iteration helper return value

Document the fact that the strategy function passed in can
control whether to continue iterating or not.

Suggested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: provide a helper to check if a queue is busy

Returns true if the queue currently has requests pending,
false if not.

DM can use this to replace the atomic_inc/dec they do per device
to see if a device is busy.

Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq-tag: change busy_iter_fn to return whether to continue or not

We have this functionality in sbitmap, but we don't export it in
blk-mq for users of the tags busy iteration. This can be useful
for stopping the iteration, if the caller doesn't need to find
more requests.

Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Get rid of 'nested' acquisition of loop_ctl_mutex

The nested acquisition of loop_ctl_mutex (->lo_ctl_mutex back then) has
been introduced by commit f028f3b2f987e "loop: fix circular locking in
loop_clr_fd()" to fix lockdep complains about bd_mutex being acquired
after lo_ctl_mutex during partition rereading. Now that these are
properly fixed, let's stop fooling lockdep.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Avoid circular locking dependency between loop_ctl_mutex and bd_mutex

Code in loop_change_fd() drops reference to the old file (and also the
new file in a failure case) under loop_ctl_mutex. Similarly to a
situation in loop_set_fd() this can create a circular locking dependency
if this was the last reference holding the file open. Delay dropping of
the file reference until we have released loop_ctl_mutex.

Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Fix deadlock when calling blkdev_reread_part()

Calling blkdev_reread_part() under loop_ctl_mutex causes lockdep to
complain about circular lock dependency between bdev->bd_mutex and
lo->lo_ctl_mutex. The problem is that on loop device open or close
lo_open() and lo_release() get called with bdev->bd_mutex held and they
need to acquire loop_ctl_mutex. OTOH when loop_reread_partitions() is
called with loop_ctl_mutex held, it will call blkdev_reread_part() which
acquires bdev->bd_mutex. See syzbot report for details [1].

Move call to blkdev_reread_part() in __loop_clr_fd() from under
loop_ctl_mutex to finish fixing of the lockdep warning and the possible
deadlock.

[1] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d1588

Reported-by: syzbot <syzbot+4684a000d5abdade83fac55b1e7d1f935ef1936e@syzkaller.appspotmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Move loop_reread_partitions() out of loop_ctl_mutex

Calling loop_reread_partitions() under loop_ctl_mutex causes lockdep to
complain about circular lock dependency between bdev->bd_mutex and
lo->lo_ctl_mutex. The problem is that on loop device open or close
lo_open() and lo_release() get called with bdev->bd_mutex held and they
need to acquire loop_ctl_mutex. OTOH when loop_reread_partitions() is
called with loop_ctl_mutex held, it will call blkdev_reread_part() which
acquires bdev->bd_mutex. See syzbot report for details [1].

Move all calls of loop_rescan_partitions() out of loop_ctl_mutex to
avoid lockdep warning and fix deadlock possibility.

[1] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d1588

Reported-by: syzbot <syzbot+4684a000d5abdade83fac55b1e7d1f935ef1936e@syzkaller.appspotmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Move special partition reread handling in loop_clr_fd()

The call of __blkdev_reread_part() from loop_reread_partition() happens
only when we need to invalidate partitions from loop_release(). Thus
move a detection for this into loop_clr_fd() and simplify
loop_reread_partition().

This makes loop_reread_partition() safe to use without loop_ctl_mutex
because we use only lo->lo_number and lo->lo_file_name in case of error
for reporting purposes (thus possibly reporting outdate information is
not a big deal) and we are safe from 'lo' going away under us by
elevated lo->lo_refcnt.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Push loop_ctl_mutex down to loop_change_fd()

Push loop_ctl_mutex down to loop_change_fd(). We will need this to be
able to call loop_reread_partitions() without loop_ctl_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Push loop_ctl_mutex down to loop_set_fd()

Push lo_ctl_mutex down to loop_set_fd(). We will need this to be able to
call loop_reread_partitions() without lo_ctl_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Push loop_ctl_mutex down to loop_set_status()

Push loop_ctl_mutex down to loop_set_status(). We will need this to be
able to call loop_reread_partitions() without loop_ctl_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Push loop_ctl_mutex down to loop_get_status()

Push loop_ctl_mutex down to loop_get_status() to avoid the unusual
convention that the function gets called with loop_ctl_mutex held and
releases it.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Push loop_ctl_mutex down into loop_clr_fd()

loop_clr_fd() has a weird locking convention that is expects
loop_ctl_mutex held, releases it on success and keeps it on failure.
Untangle the mess by moving locking of loop_ctl_mutex into
loop_clr_fd().

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Split setting of lo_state from loop_clr_fd

Move setting of lo_state to Lo_rundown out into the callers. That will
allow us to unlock loop_ctl_mutex while the loop device is protected
from other changes by its special state.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Push lo_ctl_mutex down into individual ioctls

Push acquisition of lo_ctl_mutex down into individual ioctl handling
branches. This is a preparatory step for pushing the lock down into
individual ioctl handling functions so that they can release the lock as
they need it. We also factor out some simple ioctl handlers that will
not need any special handling to reduce unnecessary code duplication.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Get rid of loop_index_mutex

Now that loop_ctl_mutex is global, just get rid of loop_index_mutex as
there is no good reason to keep these two separate and it just
complicates the locking.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

loop: Fold __loop_release into loop_release

__loop_release() has a single call site. Fold it there. This is
currently not a huge win but it will make following replacement of
loop_index_mutex more obvious.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/loop: Use global lock for ioctl() operation.

syzbot is reporting NULL pointer dereference [1] which is caused by
race condition between ioctl(loop_fd, LOOP_CLR_FD, 0) versus
ioctl(other_loop_fd, LOOP_SET_FD, loop_fd) due to traversing other
loop devices at loop_validate_file() without holding corresponding
lo->lo_ctl_mutex locks.

Since ioctl() request on loop devices is not frequent operation, we don't
need fine grained locking. Let's use global lock in order to allow safe
traversal at loop_validate_file().

Note that syzbot is also reporting circular locking dependency between
bdev->bd_mutex and lo->lo_ctl_mutex [2] which is caused by calling
blkdev_reread_part() with lock held. This patch does not address it.

[1] https://syzkaller.appspot.com/bug?id=f3cfe26e785d85f9ee259f385515291d21bd80a3
[2] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d15889

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+bf89c128e05dd6c62523@syzkaller.appspotmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/loop: Don't grab "struct file" for vfs_getattr() operation.

vfs_getattr() needs "struct path" rather than "struct file".
Let's use path_get()/path_put() rather than get_file()/fput().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ms_block: remove unused pointer 'set'

Pointer 'set' is declared but not used, remove it. Cleans up warning:

warning: unused variable ‘set’ [-Wunused-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

sunvdc: fix compiler warning

Stephen reports:

After merging the block tree, today's linux-next build (sparc64 defconfig)
produced this warning:

/home/sfr/next/next/drivers/block/sunvdc.c: In function 'init_queue':
/home/sfr/next/next/drivers/block/sunvdc.c:788:6: warning: unused variable 'ret' [-Wunused-variable]
  int ret;
      ^~~

Kill the unused variable.

Fixes: fa182a1fa97d ("sunvdc: convert to blk-mq")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add separate poll queue map

Adds support for defining a variable number of poll queues, currently
configurable with the 'poll_queues' module parameter. Defaults to
a single poll queue.

And now we finally have poll support without triggering interrupts!

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: add REQ_HIPRI and inherit it from IOCB_HIPRI

We use IOCB_HIPRI to poll for IO in the caller instead of scheduling.
This information is not available for (or after) IO submission. The
driver may make different queue choices based on the type of IO, so
make the fact that we will poll for this IO known to the lower layers
as well.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: utilize two queue maps, one for reads and one for writes

NVMe does round-robin between queues by default, which means that
sharing a queue map for both reads and writes can be problematic
in terms of read servicing. It's much easier to flood the queue
with writes and reduce the read servicing.

Implement two queue maps, one for reads and one for writes. The
write queue count is configurable through the 'write_queues'
parameter.

By default, we retain the previous behavior of having a single
queue set, shared between reads and writes. Setting 'write_queues'
to a non-zero value will create two queue sets, one for reads and
one for writes, the latter using the configurable number of
queues (hardware queue counts permitting).

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: initial support for multiple queue maps

Add a queue offset to the tag map. This enables users to map
iteratively, for each queue map type they support.

Bump maximum number of supported maps to 2, we're now fully
able to support more than 1 map.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: improve plug list sorting

Currently we only look at the software queue, but with support
for multiple maps, we should also look at the hardware queue.
This is important since we'll flush out the request list if
either the software queue or hardware queue don't match.

This sorts by software queue first, then hardware queue if
that differs. Finally we sort by request location like before.
This minimizes the flush points per plug list.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: cleanup and improve list insertion

It's somewhat strange to have a list insertion function that
relies on the fact that the caller has mapped things correctly.
Pass in the hardware queue directly for insertion, which makes
for a much cleaner interface and implementation.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: cache request hardware queue mapping

We call blk_mq_map_queue() a lot, at least two times for each
request per IO, sometimes more. Since we now have an indirect
call as well in that function. cache the mapping so we don't
have to re-call blk_mq_map_queue() for the same request
multiple times.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: separate number of hardware queues from nr_cpu_ids

With multiple maps, nr_cpu_ids is no longer the maximum number of
hardware queues we support on a given devices. The initializer of
the tag_set can have set ->nr_hw_queues larger than the available
number of CPUs, since we can exceed that with multiple queue maps.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: support multiple hctx maps

Add support for the tag set carrying multiple queue maps, and
for the driver to inform blk-mq how many it wishes to support
through setting set->nr_maps.

This adds an mq_ops helper for drivers that support more than 1
map, mq_ops->rq_flags_to_type(). The function takes request/bio
flags and CPU, and returns a queue map index for that. We then
use the type information in blk_mq_map_queue() to index the map
set.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: add 'type' attribute to the sysfs hctx directory

It can be useful for a user to verify what type a given hardware
queue is, expose this information in sysfs.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: allow software queue to map to multiple hardware queues

The mapping used to be dependent on just the CPU location, but
now it's a tuple of (type, cpu) instead. This is a prep patch
for allowing a single software queue to map to multiple hardware
queues. No functional changes in this patch.

This changes the software queue count to an unsigned short
to save a bit of space. We can still support 64K-1 CPUs,
which should be enough. Add a check to catch a wrap.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: pass in request/bio flags to queue mapping

Prep patch for being able to place request based not just on
CPU location, but also on the type of request.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: provide dummy blk_mq_map_queue_type() helper

Doesn't do anything right now, but it's needed as a prep patch
to get the interfaces right.

While in there, correct the blk_mq_map_queue() CPU type to an unsigned
int.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: abstract out queue map

This is in preparation for allowing multiple sets of maps per
queue, if so desired.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: kill q->mq_map

It's just a pointer to set->mq_map, use that instead. Move the
assignment a bit earlier, so we always know it's valid.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Merge branch 'irq/for-block' of git://git./linux/kernel/git/tip/tip into for-4.21/block

Pull in the irq affinity commits, that are staged through Thomas's
tree.

* 'irq/for-block' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/affinity: Add support for allocating interrupt sets
  genirq/affinity: Pass first vector to __irq_build_affinity_masks()
  genirq/affinity: Move two stage affinity spreading into a helper function
  genirq/affinity: Spread IRQs to all available NUMA nodes

block: kill request ->cpu member

This was used for completion placement for the legacy path,
but for mq we have rq->mq_ctx->cpu for that. Add a helper
to get the request CPU assignment, as the mq_ctx type is
private to blk-mq.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: get rid of q->softirq_done_fn()

With the legacy path gone, all we do is funnel it through the
mq_ops->complete() operation.

Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: get rid of blk_queued_rq()

No point in hiding what this does, just open code it in the
one spot where we are still using it.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-merge: kill dead queue lock held check

This is dead code, any queue reaching this part has mq_ops
attached.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove req_no_special_merge() from merging code

It'll always be false at this point, just remove it.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: kill request slab cache

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove request_list code

It's now dead code, nobody uses it.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

bsg: move bsg-lib parts outside of request queue

Get rid of the special bsg job fn and timeout handler, move them
into a private bsg_set instead.

Mostly from Christoph, with fixes for error handling and cleanups.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: kill legacy parts of timeout handling

The only user of legacy timing now is BSG, which is invoked
from the mq timeout handler. Kill the legacy code, and rename
the q->rq_timed_out_fn to q->bsg_job_timeout_fn.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove __blk_put_request()

Now there's no difference between blk_put_request() and
__blk_put_request() anymore, get rid of the underscore version and
convert the few callers.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: get rid of MQ scheduler ops union

This is a remnant of when we had ops for both SQ and MQ
schedulers. Now it's just MQ, so get rid of the union.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove dead elevator code

This removes a bunch of core and elevator related code. On the core
front, we remove anything related to queue running, draining,
initialization, plugging, and congestions. We also kill anything
related to request allocation, merging, retrieval, and completion.

Remove any checking for single queue IO schedulers, as they no
longer exist. This means we can also delete a bunch of code related
to request issue, adding, completion, etc - and all the SQ related
ops and helpers.

Also kill the load_default_modules(), as all that did was provide
for a way to load the default single queue elevator.

Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove legacy IO schedulers

Retain the deadline documentation, as that carries over to mq-deadline
as well.

Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: cleanup kick/queued handling

Now that blk_flush_queue_rq() always returns false, we can
remove that return value. That bubbles through the stack,
allowing us to remove a bunch of state tracking around it.

Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove non mq parts from the flush code

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove legacy rq tagging

It's now unused, kill it.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-cgroup: remove legacy queue bypassing

We only support mq devices now.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-wbt: kill check for legacy queue type

Everything is blk-mq at this point, so it doesn't make any sense
to have this option available as it does nothing.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove blk_complete_request()

It's now unused.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

bsg: convert to use blk-mq

Requires a few changes to the FC transport class as well.

Cc: linux-scsi@vger.kernel.org
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Tested-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

bsg: provide bsg_remove_queue() helper

All drivers do unregister + cleanup, provide a helper for that.

Cc: linux-scsi@vger.kernel.org
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

bsg: pass in desired timeout handler

This will ease in the conversion to blk-mq, where we can't set
a timeout handler after queue init.

Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: linux-scsi@vger.kernel.org
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

dasd: remove dead code

Since e443343e509a we haven't had a request_fn attached to
this driver, hence any code inside an if (q->request_fn) is
unreachable.

Fixes: e443343e509a ("s390/dasd: blk-mq conversion")
[sth: Keep and fix the dasd_info->chanq_len counter.]
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove q->lld_busy_fn()

Nobody is using the legacy path for blk_lld_busy() anymore, remove
it.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: kill off the legacy IO path

This removes the legacy (non-mq) IO path for SCSI.

Cc: linux-scsi@vger.kernel.org
Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: provide mq_ops->busy() hook

Only the SCSI legacy path provides a way to check if target is
currently busy, provide the same for the MQ path.

Cc: linux-scsi@vger.kernel.org
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: provide mq_ops->busy() hook

We'll hook into this from blk_lld_busy(), allowing blk-mq to also
return whether or not a given queue currently has requests in
progress.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: remove legacy check in queue blk_freeze_queue()

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: remove the request_list usage

We don't do anything with it, that's just the legacy path.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ide: convert to blk-mq

ide-disk and ide-cd tested as working just fine, ide-tape and
ide-floppy haven't. But the latter don't require changes, so they
should work without issue.

Add helper function to insert a request from a work queue, since we
cannot invoke the blk-mq request insertion from IRQ context.

Cc: David Miller <davem@davemloft.net>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mspro_block: convert to blk-mq

Straight forward conversion, there's room for improvement.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ms_block: convert to blk-mq

Straight forward conversion, room for optimization in how everything
is punted to a work queue. Also looks plenty racy all over the map,
with the state changes. I fixed a bunch of them up while doing the
conversion, but there are surely more.

Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

sunvdc: convert to blk-mq

Convert from the old request_fn style driver to blk-mq.

Cc: David Miller <davem@davemloft.net>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

null_blk: Add conventional zone configuration for zoned support

Allow the creation of conventional zones by adding the zone_nr_conv
configuration attribute. This new attribute is used only for zoned devices
and indicates the number of conventional zones to create. The default value
is 0. Since host-managed zoned block devices must always have at least one
sequential zone, if the value of zone_nr_conv is larger than or equal to
the total number of zones of the device nr_zones, zone_nr_conv is
automatically changed to nr_zones - 1.

Reviewed-by: Matias Bjorling <matias.bjorling@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Masato Suzuki <masato.suzuki@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Merge tag 'hwmon-for-v4.20-rc2' of git://git./linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - Remove bogus __init annotations in ibmpowernv driver

 - Fix double-free in error handling of __hwmon_device_register()

* tag 'hwmon-for-v4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (ibmpowernv) Remove bogus __init annotations
  hwmon: (core) Fix double-free in __hwmon_device_register()

Merge tag 'armsoc-fixes' of git://git./linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Olof Johansson:
 "A few more fixes that have come in, and one revert of a previous fix.

  I was a bit too trigger happy to enable PREEMPT on multi_v7_defconfig,
  and it ended up regressing at least BeagleBone XM boards. While we get
  that debugged for next merge window, let's disable it again.

  Beyond that:

   - Stratix change to fix multicast filtering

   - Minor DT fixes for Renesas and i.MX

   - Ethernet fix for a Renesas board (switching main interfaces)

   - Ethernet phy regulator fix for i.MX6SX"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  arm64: dts: stratix10: fix multicast filtering
  ARM: defconfig: Disable PREEMPT again on  multi_v7
  arm64: dts: renesas: condor: switch from EtherAVB to GEther
  dt-bindings: arm: Fix RZ/G2E part number
  arm64: dts: renesas: r8a7795: add missing dma-names on hscif2
  ARM: dts: imx6sx-sdb: Fix enet phy regulator
  ARM: dts: fsl: Fix improperly quoted stdout-path values
  ARM: dts: imx6sll: fix typo for fsl,imx6sll-i2c node

Merge branch 'for-linus' of git://git./linux/kernel/git/hid/hid

Pull HID fixes from Jiri Kosina:

 - hid.git is moving towards group maintainership (where group is myself
   and Benjamin Tissoires), therefore this pull request updates
   MAINTAINERS accordingly

 - fix for hid-asus config dependency from Arnd Bergmann

 - two device-specific quirks for i2c-hid from Julian Sax and Kai-Heng
   Feng

 - other few small assorted fixes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
  HID: fix up .raw_event() documentation
  HID: asus: fix build warning wiht CONFIG_ASUS_WMI disabled
  HID: i2c-hid: add Direkt-Tek DTLAPY133-1 to descriptor override
  HID: moving to group maintainership model
  HID: alps: allow incoming reports when only the trackstick is opened
  Revert "HID: add NOGET quirk for Eaton Ellipse MAX UPS"
  HID: i2c-hid: Add a small delay after sleep command for Raydium touchpanel
  HID: hiddev: fix potential Spectre v1

Merge tag 'stratix10_dts_fix_for_v4.20' of git://git./linux/kernel/git/dinguyen/linux into fixes

ARM: dts: stratix10: fix multicast filtering

On Stratix 10, the EMAC has 256 hash buckets for multicast filtering. This
needs to be specified in DTS, otherwise the stmmac driver defaults to 64
buckets and initializes the filter incorrectly. As a result, e.g. valid
IPv6 multicast traffic ends up being dropped.

* tag 'stratix10_dts_fix_for_v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux:
  arm64: dts: stratix10: fix multicast filtering

Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'renesas-fixes-for-v4.20' of https://git./linux/kernel/git/horms/renesas into fixes

Renesas ARM Based SoC Fixes for v4.20

* R-Car V3H (r8a77980) based Condor board
  - Switch from EtherAVB to GEther to match offical boards

* RZ/G2E (ra8774c0) SoC: correct documentation of part number

* R-Car H3 (r8a7795) SoC: reinstate all DMA channels on HSCIF2

* tag 'renesas-fixes-for-v4.20' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
  arm64: dts: renesas: condor: switch from EtherAVB to GEther
  dt-bindings: arm: Fix RZ/G2E part number
  arm64: dts: renesas: r8a7795: add missing dma-names on hscif2

Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'trace-v4.20-rc1' of git://git./linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Masami found a slight bug in his code where he transposed the
  arguments of a call to strpbrk.

  The reason this wasn't detected in our tests is that the only way this
  would transpire is when a kprobe event with a symbol offset is
  attached to a function that belongs to a module that isn't loaded yet.
  When the kprobe trace event is added, the offset would be truncated
  after it was parsed, and when the module is loaded, it would use the
  symbol without the offset (as the nul character added by the parsing
  would not be replaced with the original character)"

* tag 'trace-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/kprobes: Fix strpbrk() argument order