Commit Graph

933173 Commits

Author SHA1 Message Date
Randy Dunlap
d958e343bd block: blk-timeout: delete duplicated word
Drop the repeated word "request".
Change to the correct kernel-doc notation for function name separtor.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-31 16:29:47 -06:00
Randy Dunlap
c4aecaa256 block: blk-mq-sched: delete duplicated word
Drop the repeated word "to".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-31 16:29:47 -06:00
Randy Dunlap
70f15a4fd9 block: blk-mq: delete duplicated word
Drop the repeated word "the".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-31 16:29:47 -06:00
Randy Dunlap
0d20dcc277 block: genhd: delete duplicated words
Drop the repeated word "to" in multiple places.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-31 16:29:47 -06:00
Randy Dunlap
5b8f65e1f9 block: elevator: delete duplicated word and fix typos
Drop the repeated word "the".
Fix typos of "features" and "specified".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-31 16:29:47 -06:00
Randy Dunlap
3cf1488917 block: bio: delete duplicated words
Drop the repeated words "a" and "the".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-31 16:29:47 -06:00
Randy Dunlap
f06678af91 block: bfq-iosched: fix duplicated word
Change "at at" to "at a".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-31 16:29:47 -06:00
Chengming Zhou
1bf6ece573 iocost_monitor: start from the oldest usage index
iocg usage_idx is the latest usage index, we should start from the
oldest usage index to show the consecutive NR_USAGE_SLOTS usages.

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-30 11:45:29 -06:00
Chengming Zhou
d9012a59db iocost: Fix check condition of iocg abs_vdebt
We shouldn't skip iocg when its abs_vdebt is not zero.

Fixes: 0b80f9866e ("iocost: protect iocg->abs_vdebt with iocg->waitq.lock")
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-30 11:45:12 -06:00
Daniel Wagner
0516c2f6ae block: Remove callback typedefs for blk_mq_ops
No need to define typedefs for the callbacks, because there is not a
single user except blk_mq_ops.

Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-28 10:22:19 -06:00
Daniel Wagner
08c875cbf4 block: Use non _rcu version of list functions for tag_set_list
tag_set_list is only accessed under the tag_set_lock lock. There is
no need for using the _rcu list functions.

The _rcu list function were introduced to allow read access to the
tag_set_list protected under RCU, see 705cda97ee ("blk-mq: Make it
safe to use RCU to iterate over blk_mq_tag_set.tag_list") and
05b7941394 ("Revert "blk-mq: don't handle TAG_SHARED in restart"").
Those changes got reverted later but the cleanup commit missed a
couple of places to undo the changes.

Fixes: 97889f9ac2 ("blk-mq: remove synchronize_rcu() from blk_mq_del_queue_tag_set()"
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-28 09:37:09 -06:00
Boris Burkov
ef45fe470e blk-cgroup: show global disk stats in root cgroup io.stat
In order to improve consistency and usability in cgroup stat accounting,
we would like to support the root cgroup's io.stat.

Since the root cgroup has processes doing io even if the system has no
explicitly created cgroups, we need to be careful to avoid overhead in
that case.  For that reason, the rstat algorithms don't handle the root
cgroup, so just turning the file on wouldn't give correct statistics.

To get around this, we simulate flushing the iostat struct by filling it
out directly from global disk stats. The result is a root cgroup io.stat
file consistent with both /proc/diskstats and io.stat.

Note that in order to collect the disk stats, we needed to iterate over
devices. To facilitate that, we had to change the linkage of a disk_type
to external so that it can be used from blk-cgroup.c to iterate over
disks.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Boris Burkov <boris@bur.io>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-17 20:18:00 -06:00
Boris Burkov
cd1fc4b98f blk-cgroup: make iostat functions visible to stat printing
Previously, the code which printed io.stat only needed access to the
generic rstat flushing code, but since we plan to write some more
specific code for preparing root cgroup stats, we need to manipulate
iostat structs directly. Since declaring static functions ahead does not
seem like common practice in this file, simply move the iostat functions
up. We only plan to use blkg_iostat_set, but it seems better to keep them
all together.

Signed-off-by: Boris Burkov <boris@bur.io>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-17 20:17:59 -06:00
Coly Li
9b15d109a6 block: improve discard bio alignment in __blkdev_issue_discard()
This patch improves discard bio split for address and size alignment in
__blkdev_issue_discard(). The aligned discard bio may help underlying
device controller to perform better discard and internal garbage
collection, and avoid unnecessary internal fragment.

Current discard bio split algorithm in __blkdev_issue_discard() may have
non-discarded fregment on device even the discard bio LBA and size are
both aligned to device's discard granularity size.

Here is the example steps on how to reproduce the above problem.
- On a VMWare ESXi 6.5 update3 installation, create a 51GB virtual disk
  with thin mode and give it to a Linux virtual machine.
- Inside the Linux virtual machine, if the 50GB virtual disk shows up as
  /dev/sdb, fill data into the first 50GB by,
        # dd if=/dev/zero of=/dev/sdb bs=4096 count=13107200
- Discard the 50GB range from offset 0 on /dev/sdb,
        # blkdiscard /dev/sdb -o 0 -l 53687091200
- Observe the underlying mapping status of the device
        # sg_get_lba_status /dev/sdb -m 1048 --lba=0
  descriptor LBA: 0x0000000000000000  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000000000800  blocks: 16773120  deallocated
  descriptor LBA: 0x0000000000fff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000001000000  blocks: 8386560  deallocated
  descriptor LBA: 0x00000000017ff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000001800000  blocks: 8386560  deallocated
  descriptor LBA: 0x0000000001fff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000002000000  blocks: 8386560  deallocated
  descriptor LBA: 0x00000000027ff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000002800000  blocks: 8386560  deallocated
  descriptor LBA: 0x0000000002fff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000003000000  blocks: 8386560  deallocated
  descriptor LBA: 0x00000000037ff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000003800000  blocks: 8386560  deallocated
  descriptor LBA: 0x0000000003fff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000004000000  blocks: 8386560  deallocated
  descriptor LBA: 0x00000000047ff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000004800000  blocks: 8386560  deallocated
  descriptor LBA: 0x0000000004fff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000005000000  blocks: 8386560  deallocated
  descriptor LBA: 0x00000000057ff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000005800000  blocks: 8386560  deallocated
  descriptor LBA: 0x0000000005fff800  blocks: 2048  mapped (or unknown)
  descriptor LBA: 0x0000000006000000  blocks: 6291456  deallocated
  descriptor LBA: 0x0000000006600000  blocks: 0  deallocated

Although the discard bio starts at LBA 0 and has 50<<30 bytes size which
are perfect aligned to the discard granularity, from the above list
these are many 1MB (2048 sectors) internal fragments exist unexpectedly.

The problem is in __blkdev_issue_discard(), an improper algorithm causes
an improper bio size which is not aligned.

 25 int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
 26                 sector_t nr_sects, gfp_t gfp_mask, int flags,
 27                 struct bio **biop)
 28 {
 29         struct request_queue *q = bdev_get_queue(bdev);
   [snipped]
 56
 57         while (nr_sects) {
 58                 sector_t req_sects = min_t(sector_t, nr_sects,
 59                                 bio_allowed_max_sectors(q));
 60
 61                 WARN_ON_ONCE((req_sects << 9) > UINT_MAX);
 62
 63                 bio = blk_next_bio(bio, 0, gfp_mask);
 64                 bio->bi_iter.bi_sector = sector;
 65                 bio_set_dev(bio, bdev);
 66                 bio_set_op_attrs(bio, op, 0);
 67
 68                 bio->bi_iter.bi_size = req_sects << 9;
 69                 sector += req_sects;
 70                 nr_sects -= req_sects;
   [snipped]
 79         }
 80
 81         *biop = bio;
 82         return 0;
 83 }
 84 EXPORT_SYMBOL(__blkdev_issue_discard);

At line 58-59, to discard a 50GB range, req_sects is set as return value
of bio_allowed_max_sectors(q), which is 8388607 sectors. In the above
case, the discard granularity is 2048 sectors, although the start LBA
and discard length are aligned to discard granularity, req_sects never
has chance to be aligned to discard granularity. This is why there are
some still-mapped 2048 sectors fragment in every 4 or 8 GB range.

If req_sects at line 58 is set to a value aligned to discard_granularity
and close to UNIT_MAX, then all consequent split bios inside device
driver are (almostly) aligned to discard_granularity of the device
queue. The 2048 sectors still-mapped fragment will disappear.

This patch introduces bio_aligned_discard_max_sectors() to return the
the value which is aligned to q->limits.discard_granularity and closest
to UINT_MAX. Then this patch replaces bio_allowed_max_sectors() with
this new routine to decide a more proper split bio length.

But we still need to handle the situation when discard start LBA is not
aligned to q->limits.discard_granularity, otherwise even the length is
aligned, current code may still leave 2048 fragment around every 4GB
range. Therefore, to calculate req_sects, firstly the start LBA of
discard range is checked (including partition offset), if it is not
aligned to discard granularity, the first split location should make
sure following bio has bi_sector aligned to discard granularity. Then
there won't be still-mapped fragment in the middle of the discard range.

The above is how this patch improves discard bio alignment in
__blkdev_issue_discard(). Now with this patch, after discard with same
command line mentiond previously, sg_get_lba_status returns,
descriptor LBA: 0x0000000000000000  blocks: 106954752  deallocated
descriptor LBA: 0x0000000006600000  blocks: 0  deallocated

We an see there is no 2048 sectors segment anymore, everything is clean.

Reported-and-tested-by: Acshai Manoj <acshai.manoj@microfocus.com>
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Enzo Matsumiya <ematsumiya@suse.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-17 07:15:10 -06:00
Coly Li
ecdef9f459 block: change REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL to be odd numbers
Currently REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL are defined as
even numbers 6 and 8, such zone reset bios are treated as READ bios by
bio_data_dir(), which is obviously misleading.

The macro bio_data_dir() is defined in include/linux/bio.h as,
 55 #define bio_data_dir(bio) \
 56         (op_is_write(bio_op(bio)) ? WRITE : READ)

And op_is_write() is defined in include/linux/blk_types.h as,
397 static inline bool op_is_write(unsigned int op)
398 {
399         return (op & 1);
400 }

The convention of op_is_write() is when there is data transfer then the
op code should be odd number, and treat as a write op. bio_data_dir()
treats all bio direction as READ if op_is_write() reports false, and
WRITE if op_is_write() reports true.

Because REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL are even numbers,
although they don't transfer data but reporting them as READ bio by
bio_data_dir() is misleading and might be wrong. Because these two
commands will reset the writer pointers of the resetting zones, and all
content after the reset write pointer will be invalid and unaccessible,
obviously they are not READ bios in any means.

This patch changes REQ_OP_ZONE_RESET from 6 to 15, and changes
REQ_OP_ZONE_RESET_ALL from 8 to 17. Now bios with these two op code
can be treated as WRITE by bio_data_dir(). Although they don't transfer
data, now we keep them consistent with REQ_OP_DISCARD and
REQ_OP_WRITE_ZEROES with the ituition that they change on-media content
and should be WRITE request.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jens Axboe <axboe@fb.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Shaun Tancheff <shaun.tancheff@seagate.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-17 07:15:10 -06:00
Yufen Yu
b5718d6c00 block: defer flush request no matter whether we have elevator
Commit 7520872c0c ("block: don't defer flushes on blk-mq + scheduling")
tried to fix deadlock for cycled wait between flush requests and data
request into flush_data_in_flight. The former holded all driver tags
and wait for data request completion, but the latter can not complete
for waiting free driver tags.

After commit 923218f616 ("blk-mq: don't allocate driver tag upfront
for flush rq"), flush requests will not get driver tag before queuing
into flush queue.

* With elevator, flush request just get sched_tags before inserting
  flush queue. It will not get driver tag until issue them to driver.
  data request on list fq->flush_data_in_flight will complete in
  the end.

* Without elevator, each flush request will get a driver tag when
  allocate request. Then data request on fq->flush_data_in_flight
  don't worry about lacking driver tag.

In both of these cases, cycled wait cannot be true. So we may allow
to defer flush request.

Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-17 07:14:28 -06:00
Wei Yongjun
943c4d9074 block: make blk_timeout_init() static
The sparse tool complains as follows:

block/blk-timeout.c:93:12: warning:
 symbol 'blk_timeout_init' was not declared. Should it be static?

Function blk_timeout_init() is not used outside of blk-timeout.c, so
mark it static.

Fixes: 9054650fac ("block: relax jiffies rounding for timeouts")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-17 07:13:42 -06:00
John Ogness
ab96bbab46 block: remove retry loop in ioc_release_fn()
The reverse-order double lock dance in ioc_release_fn() is using a
retry loop. This is a problem on PREEMPT_RT because it could preempt
the task that would release q->queue_lock and thus live lock in the
retry loop.

RCU is already managing the freeing of the request queue and icq. If
the trylock fails, use RCU to guarantee that the request queue and
icq are not freed and re-acquire the locks in the correct order,
allowing forward progress.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-16 10:22:15 -06:00
John Ogness
a43f085f87 block: remove unnecessary ioc nested locking
The legacy CFQ IO scheduler could call put_io_context() in its exit_icq()
elevator callback. This led to a lockdep warning, which was fixed in
commit d8c66c5d59 ("block: fix lockdep warning on io_context release
put_io_context()") by using a nested subclass for the ioc spinlock.
However, with commit f382fb0bce ("block: remove legacy IO schedulers")
the CFQ IO scheduler no longer exists.

The BFQ IO scheduler also implements the exit_icq() elevator callback but
does not call put_io_context().

The nested subclass for the ioc spinlock is no longer needed. Since it
existed as an exception and no longer applies, remove the nested subclass
usage.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-16 10:22:15 -06:00
Christoph Hellwig
5b642d8b9f block: integrate bd_start_claiming into __blkdev_get
bd_start_claiming duplicates a lot of the work done in __blkdev_get.
Integrate the two functions to avoid the duplicate work, and to do the
right thing for the md -ERESTARTSYS corner case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-16 09:35:44 -06:00
Christoph Hellwig
ecbe6bc000 block: use bd_prepare_to_claim directly in the loop driver
The arcane magic in bd_start_claiming is only needed to be able to claim
a block_device that hasn't been fully set up.  Switch the loop driver
that claims from the ioctl path with a fully set up struct block_device
to just use the much simpler bd_prepare_to_claim directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-16 09:35:44 -06:00
Christoph Hellwig
58e46ed9cc block: refactor bd_start_claiming
Move the locking and assignment of bd_claiming from bd_start_claiming to
bd_prepare_to_claim.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-16 09:35:44 -06:00
Christoph Hellwig
c5638ab417 block: simplify the restart case in __blkdev_get
Insted of duplicating all the cleanup logic jump to the code that cleans
up anyway, and restart after that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-16 09:35:44 -06:00
Jens Axboe
e791ee6885 Revert "blk-rq-qos: remove redundant finish_wait to rq_qos_wait."
This reverts commit 826f2f48da.

Qian Cai reports that this commit causes stalls with swap. Revert until
the reason can be figured out.

Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-15 09:33:37 -06:00
Ming Lei
d0f0f1b4c5 block: always remove partitions from blk_drop_partitions()
In theory, when GENHD_FL_NO_PART_SCAN is set, no partitions can be created
on one disk. However, ioctl(BLKPG, BLKPG_ADD_PARTITION) doesn't check
GENHD_FL_NO_PART_SCAN, so partitions still can be added even though
GENHD_FL_NO_PART_SCAN is set.

So far blk_drop_partitions() only removes partitions when disk_part_scan_enabled()
return true. This way can make ghost partition on loop device after changing/clearing
FD in case that PARTSCAN is disabled, such as partitions can be added
via 'parted' on loop disk even though GENHD_FL_NO_PART_SCAN is set.

Fix this issue by always removing partitions in blk_drop_partitions(), and
this way is correct because the current code supposes that no partitions
can be added in case of GENHD_FL_NO_PART_SCAN.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-15 09:23:42 -06:00
Jens Axboe
9054650fac block: relax jiffies rounding for timeouts
In doing high IOPS testing, blk-mq is generally pretty well optimized.
There are a few things that stuck out as using more CPU than what is
really warranted, and one thing is the round_jiffies_up() that we do
twice for each request. That accounts for about 0.8% of the CPU in
my testing.

We can make this cheaper by avoiding an integer division, by just adding
a rough HZ mask that we can AND with instead. The timeouts are only on a
second granularity already, we don't have to be that accurate here and
this patch barely changes that. All we care about is nice grouping.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-15 09:23:35 -06:00
Baolin Wang
87890092ee blk-mq: remove redundant validation in __blk_mq_end_request()
We've already validated the 'q->elevator' before calling
->ops.completed_request() in blk_mq_sched_completed_request(), thus no
need to validate rq->internal_tag again. Rmove it.

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-10 07:58:33 -06:00
Baolin Wang
106e71c512 blk-mq: Remove unnecessary local variable
Remove unnecessary local variable 'ret' in blk_mq_dispatch_hctx_list().

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-10 07:58:09 -06:00
Christoph Hellwig
21cf866145 writeback: remove bdi->congested_fn
Except for pktdvd, the only places setting congested bits are file
systems that allocate their own backing_dev_info structures.  And
pktdvd is a deprecated driver that isn't useful in stack setup
either.  So remove the dead congested_fn stacking infrastructure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>
[axboe: fixup unused variables in bcache/request.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 17:20:46 -06:00
Christoph Hellwig
8c911f3d4c writeback: remove struct bdi_writeback_congested
We never set any congested bits in the group writeback instances of it.
And for the simpler bdi-wide case a simple scalar field is all that
that is needed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 17:05:53 -06:00
Christoph Hellwig
492d76b215 writeback: remove {set,clear}_wb_congested
Just merge them into their only callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 17:05:53 -06:00
Christoph Hellwig
d5c6983845 drbd: remove a bogus bdi_rw_congested call
bdi_rw_congested returns congestion state, so calling it without
looking at the return value doesn't make much sense.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 17:05:53 -06:00
Christoph Hellwig
9eb994ec54 mmc: remove the call to check_disk_change
The mmc driver doesn't support event notifications, which means
that check_disk_change is a no-op.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:20:01 -06:00
Christoph Hellwig
3d3a6a2088 xtensa/simdisk: remove the call to check_disk_change
The simdisk driver doesn't support event notifications, which means
that check_disk_change is a no-op.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:20:01 -06:00
Christoph Hellwig
13ab64880e isofs: remove a stale comment
check_disk_change isn't for consumers of the block layer, so remove
the comment mentioning it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:20:01 -06:00
Christoph Hellwig
9a3ffbbc65 block: remove flush_disk
flush_disk has only two callers, so open code it there.  That also helps
clarifying the error message for the particular case, and allows to remove
setting bd_invalidated in check_disk_size_change, which will be cleared
again instantly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:20:01 -06:00
Christoph Hellwig
8c22eb3a77 cdrom: remove the unused cdrom_media_changed function
As well as the ->media_changed method.  All these are left over from
before the drivers were switched over to the check_events scheme.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:20:01 -06:00
Christoph Hellwig
a564e23f0f md: switch to ->check_events for media change notifications
md is the last driver using the legacy media_changed method.  Switch
it over to (not so) new ->clear_events approach, which also removes the
need for the ->revalidate_disk method.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[axboe: remove unused 'bdops' variable in disk_clear_events()]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:19:47 -06:00
Ming Lei
568f270065 blk-mq: centralise related handling into blk_mq_get_driver_tag
Move .nr_active update and request assignment into blk_mq_get_driver_tag(),
all are good to do during getting driver tag.

Meantime blk-flush related code is simplified and flush request needn't
to update the request table manually any more.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:06:42 -06:00
Ming Lei
7bf137298c blk-mq: streamline handling of q->mq_ops->queue_rq result
Current handling of q->mq_ops->queue_rq result is a bit ugly:

- two branches which needs to 'continue' have to check if the
dispatch local list is empty, otherwise one bad request may
be retrieved via 'rq = list_first_entry(list, struct request, queuelist);'

- the branch of 'if (unlikely(ret != BLK_STS_OK))' isn't easy
to follow, since it is actually one error branch.

Streamline this handling, so the code becomes more readable, meantime
potential kernel oops can be avoided in case that the last request in
local dispatch list is failed.

Fixes: fc17b6534e ("blk-mq: switch ->queue_rq return value to blk_status_t")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 16:04:39 -06:00
Christoph Hellwig
0e6e255e7a block: remove a bogus warning in __submit_bio_noacct_mq
If blk_mq_submit_bio flushes the plug list, bios for other disks can
show up on current->bio_list.  As that doesn't involve any stacking of
block device it is entirely harmless and we should not warn about
this case.

Fixes: ff93ea0ce7 ("block: shortcut __submit_bio_noacct for blk-mq drivers")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-07 11:45:59 -06:00
Christoph Hellwig
7c792f33c1 block: initialize current->bio_list[1] in __submit_bio_noacct_mq
bio_alloc_bioset references current->bio_list[1], so we need to
initialize it for the blk-mq submission path as well.

Fixes: ff93ea0ce7 ("block: shortcut __submit_bio_noacct for blk-mq drivers")
Reported-by: Qian Cai <cai@lca.pw>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-02 13:34:30 -06:00
Jens Axboe
4e2f62e566 Revert "blk-mq: put driver tag when this request is completed"
This reverts commits the following commits:

	37f4a24c24
	723bf178f1
	36a3df5a45

The last one is the culprit, but we have to go a bit deeper to get this
to revert cleanly. There's been a report that this breaks some MMC
setups [1], and also causes an issue with swap [2]. Until this can be
figured out, revert the offending commits.

[1] https://lore.kernel.org/linux-block/57fb09b1-54ba-f3aa-f82c-d709b0e6b281@samsung.com/
[2] https://lore.kernel.org/linux-block/20200702043721.GA1087@lca.pw/

Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 22:58:32 -06:00
Jens Axboe
b53ac8b891 dm: remove unused variable
Since merging the commit identified in Fixes below, we trigger this
compile time warning:

drivers/md/dm.c: In function ‘__map_bio’:
drivers/md/dm.c:1296:24: warning: unused variable ‘md’ [-Wunused-variable]
 1296 |  struct mapped_device *md = io->md;
       |                        ^~

Remove the 'md' variable.

Fixes: 5a6c35f9af ("block: remove direct_make_request")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 15:45:19 -06:00
John Garry
6bf0eb5504 sbitmap: Consider cleared bits in sbitmap_bitmap_show()
sbitmap works by maintaining separate bitmaps of set and cleared bits.
The set bits are cleared in a batch, to save the burden of continuously
locking the "word" map to unset.

sbitmap_bitmap_show() only shows the set bits (in "word"), which is not
too much use, so mask out the cleared bits.

Fixes: ea86ea2cdc ("sbitmap: ammortize cost of clearing bits")
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 10:53:00 -06:00
Christoph Hellwig
1008fe6dc3 block: remove the all_bdevs list
Instead just iterate over the inodes for the block device superblock.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 08:08:25 -06:00
Christoph Hellwig
47b5e00322 block: remove the unused bd_private field from struct block_device
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 08:08:23 -06:00
Christoph Hellwig
e556f6ba10 block: remove the bd_queue field from struct block_device
Just use bd_disk->queue instead.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 08:08:20 -06:00
Christoph Hellwig
6b7b181b67 block: remove the bd_block_size field from struct block_device
We can trivially calculate the block size from the inodes i_blkbits
variable.  Use that instead of keeping two redundant copies of the
information in slightly different formats.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 08:08:17 -06:00
Christoph Hellwig
5ff9f19231 block: simplify set_init_blocksize
The loop to increase the initial block size doesn't really make any
sense, as the AND operation won't match for powers of two if it didn't
for the initial block size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 08:08:17 -06:00