linux.git/block, branch v4.16

Merge tag 'for-linus-20180302' of git://git.kernel.dk/linux-block

2018-03-02T17:35:36+00:00

Pull block fixes from Jens Axboe:
 "A collection of fixes for this series. This is a little larger than
  usual at this time, but that's mainly because I was out on vacation
  last week. Nothing in here is major in any way, it's just two weeks of
  fixes. This contains:

   - NVMe pull from Keith, with a set of fixes from the usual suspects.

   - mq-deadline zone unlock fix from Damien, fixing an issue with the
     SMR zone locking added for 4.16.

   - two bcache fixes sent in by Michael, with changes from Coly and
     Tang.

   - comment typo fix from Eric for blktrace.

   - return-value error handling fix for nbd, from Gustavo.

   - fix a direct-io case where we don't defer to a completion handler,
     making us sleep from IRQ device completion. From Jan.

   - a small series from Jan fixing up holes around handling of bdev
     references.

   - small set of regression fixes from Jiufei, mostly fixing problems
     around the gendisk pointer -> partition index change.

   - regression fix from Ming, fixing a boundary issue with the discard
     page cache invalidation.

   - two-patch series from Ming, fixing both a core blk-mq-sched and
     kyber issue around token freeing on a requeue condition"

* tag 'for-linus-20180302' of git://git.kernel.dk/linux-block: (24 commits)
  block: fix a typo
  block: display the correct diskname for bio
  block: fix the count of PGPGOUT for WRITE_SAME
  mq-deadline: Make sure to always unlock zones
  nvmet: fix PSDT field check in command format
  nvme-multipath: fix sysfs dangerously created links
  nbd: fix return value in error handling path
  bcache: fix kcrashes with fio in RAID5 backend dev
  bcache: correct flash only vols (check all uuids)
  blktrace_api.h: fix comment for struct blk_user_trace_setup
  blockdev: Avoid two active bdev inodes for one device
  genhd: Fix BUG in blkdev_open()
  genhd: Fix use after free in __blkdev_get()
  genhd: Add helper put_disk_and_module()
  genhd: Rename get_disk() to get_disk_and_module()
  genhd: Fix leaked module reference for NVME devices
  direct-io: Fix sleep in atomic due to sync AIO
  nvme-pci: Fix nvme queue cleanup if IRQ setup fails
  block: kyber: fix domain token leak during requeue
  blk-mq: don't call io sched's .requeue_request when requeueing rq to ->dispatch
  ...

block: display the correct diskname for bio

2018-03-01T15:41:25+00:00

bio_devname use __bdevname to display the device name, and can
only show the major and minor of the part0,
Fix this by using disk_name to display the correct name.

Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index")
Reviewed-by: Omar Sandoval 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jiufei Xue 
Signed-off-by: Jens Axboe

block: fix the count of PGPGOUT for WRITE_SAME

2018-03-01T15:41:23+00:00

The vm counters is counted in sectors, so we should do the conversation
in submit_bio.

Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index")
Cc: stable@vger.kernel.org
Reviewed-by: Omar Sandoval 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jiufei Xue 
Signed-off-by: Jens Axboe

mq-deadline: Make sure to always unlock zones

2018-03-01T15:39:24+00:00

In case of a failed write request (all retries failed) and when using
libata, the SCSI error handler calls scsi_finish_command(). In the
case of blk-mq this means that scsi_mq_done() does not get called,
that blk_mq_complete_request() does not get called and also that the
mq-deadline .completed_request() method is not called. This results in
the target zone of the failed write request being left in a locked
state, preventing that any new write requests are issued to the same
zone.

Fix this by replacing the .completed_request() method with the
.finish_request() method as this method is always called whether or
not a request completes successfully. Since the .finish_request()
method is only called by the blk-mq core if a .prepare_request()
method exists, add a dummy .prepare_request() method.

Fixes: 5700f69178e9 ("mq-deadline: Introduce zone locking support")
Cc: Hannes Reinecke 
Reviewed-by: Ming Lei 
Signed-off-by: Damien Le Moal 
[ bvanassche: edited patch description ]
Signed-off-by: Bart Van Assche 
Signed-off-by: Jens Axboe

genhd: Fix BUG in blkdev_open()

2018-02-26T16:48:42+00:00

When two blkdev_open() calls for a partition race with device removal
and recreation, we can hit BUG_ON(!bd_may_claim(bdev, whole, holder)) in
blkdev_open(). The race can happen as follows:

CPU0				CPU1			CPU2
							del_gendisk()
							  bdev_unhash_inode(part1);

blkdev_open(part1, O_EXCL)	blkdev_open(part1, O_EXCL)
  bdev = bd_acquire()		  bdev = bd_acquire()
  blkdev_get(bdev)
    bd_start_claiming(bdev)
      - finds old inode 'whole'
      bd_prepare_to_claim() -> 0
							  bdev_unhash_inode(whole);
							
							
				  blkdev_get(bdev);
				    bd_start_claiming(bdev)
				      - finds new inode 'whole'
				      bd_prepare_to_claim()
					- this also succeeds as we have
					  different 'whole' here...
					- bad things happen now as we
					  have two exclusive openers of
					  the same bdev

The problem here is that block device opens can see various intermediate
states while gendisk is shutting down and then being recreated.

We fix the problem by introducing new lookup_sem in gendisk that
synchronizes gendisk deletion with get_gendisk() and furthermore by
making sure that get_gendisk() does not return gendisk that is being (or
has been) deleted. This makes sure that once we ever manage to look up
newly created bdev inode, we are also guaranteed that following
get_gendisk() will either return failure (and we fail open) or it
returns gendisk for the new device and following bdget_disk() will
return new bdev inode (i.e., blkdev_open() follows the path as if it is
completely run after new device is created).

Reported-and-analyzed-by: Hou Tao 
Tested-by: Hou Tao 
Signed-off-by: Jan Kara 
Signed-off-by: Jens Axboe

genhd: Add helper put_disk_and_module()

2018-02-26T16:48:42+00:00

Add a proper counterpart to get_disk_and_module() -
put_disk_and_module(). Currently it is opencoded in several places.

Signed-off-by: Jan Kara 
Signed-off-by: Jens Axboe

genhd: Rename get_disk() to get_disk_and_module()

2018-02-26T16:48:42+00:00

Rename get_disk() to get_disk_and_module() to make sure what the
function does. It's not a great name but at least it is now clear that
put_disk() is not it's counterpart.

Signed-off-by: Jan Kara 
Signed-off-by: Jens Axboe

genhd: Fix leaked module reference for NVME devices

2018-02-26T16:48:42+00:00

Commit 8ddcd653257c "block: introduce GENHD_FL_HIDDEN" added handling of
hidden devices to get_gendisk() but forgot to drop module reference
which is also acquired by get_disk(). Drop the reference as necessary.

Arguably the function naming here is misleading as put_disk() is *not*
the counterpart of get_disk() but let's fix that in the follow up
commit since that will be more intrusive.

Fixes: 8ddcd653257c18a669fcb75ee42c37054908e0d6
CC: Christoph Hellwig 
Signed-off-by: Jan Kara 
Signed-off-by: Jens Axboe

block: kyber: fix domain token leak during requeue

2018-02-24T22:55:54+00:00

When requeuing request, the domain token should have been freed
before re-inserting the request to io scheduler. Otherwise, the
assigned domain token will be leaked, and IO hang can be caused.

Cc: Paolo Valente 
Cc: Omar Sandoval 
Cc: stable@vger.kernel.org
Reviewed-by: Bart Van Assche 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe

blk-mq: don't call io sched's .requeue_request when requeueing rq to ->dispatch

2018-02-24T22:55:54+00:00

__blk_mq_requeue_request() covers two cases:

- one is that the requeued request is added to hctx->dispatch, such as
blk_mq_dispatch_rq_list()

- another case is that the request is requeued to io scheduler, such as
blk_mq_requeue_request().

We should call io sched's .requeue_request callback only for the 2nd
case.

Cc: Paolo Valente 
Cc: Omar Sandoval 
Fixes: bd166ef183c2 ("blk-mq-sched: add framework for MQ capable IO schedulers")
Cc: stable@vger.kernel.org
Reviewed-by: Bart Van Assche 
Acked-by: Paolo Valente 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe