diff options
| author | Ming Lei | 2021-11-09 15:11:42 +0800 |
|---|---|---|
| committer | Jens Axboe | 2021-11-09 08:14:27 -0700 |
| commit | d2b9f12b0f7cf95c43f5fd4a18688d958d39e423 (patch) | |
| tree | e9d3011d2181c8e700e39ae51bb5bafdf2f0ec63 /drivers | |
| parent | 9ef4d0209cbadb63656a7aa29fde49c27ab2b9bf (diff) | |
scsi: avoid to quiesce sdev->request_queue two times
For fixing queue quiesce race between driver and block layer(elevator
switch, update nr_requests, ...), we need to support concurrent quiesce
and unquiesce, which requires the two to be balanced.
blk_mq_quiesce_queue() calls blk_mq_quiesce_queue_nowait() for updating
quiesce depth and marking the flag, then scsi_internal_device_block() calls
blk_mq_quiesce_queue_nowait() two times actually.
Fix the double quiesce and keep quiesce and unquiesce balanced.
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Fixes: e70feb8b3e68 ("blk-mq: support concurrent queue quiesce/unquiesce")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20211109071144.181581-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 29 |
1 files changed, 14 insertions, 15 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 30f7d0b4eb73..51fcd46be265 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2630,6 +2630,14 @@ scsi_target_resume(struct scsi_target *starget) } EXPORT_SYMBOL(scsi_target_resume); +static int __scsi_internal_device_block_nowait(struct scsi_device *sdev) +{ + if (scsi_device_set_state(sdev, SDEV_BLOCK)) + return scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); + + return 0; +} + /** * scsi_internal_device_block_nowait - try to transition to the SDEV_BLOCK state * @sdev: device to block @@ -2646,24 +2654,16 @@ EXPORT_SYMBOL(scsi_target_resume); */ int scsi_internal_device_block_nowait(struct scsi_device *sdev) { - struct request_queue *q = sdev->request_queue; - int err = 0; - - err = scsi_device_set_state(sdev, SDEV_BLOCK); - if (err) { - err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); - - if (err) - return err; - } + int ret = __scsi_internal_device_block_nowait(sdev); /* * The device has transitioned to SDEV_BLOCK. Stop the * block layer from calling the midlayer with this device's * request queue. */ - blk_mq_quiesce_queue_nowait(q); - return 0; + if (!ret) + blk_mq_quiesce_queue_nowait(sdev->request_queue); + return ret; } EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait); @@ -2684,13 +2684,12 @@ EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait); */ static int scsi_internal_device_block(struct scsi_device *sdev) { - struct request_queue *q = sdev->request_queue; int err; mutex_lock(&sdev->state_mutex); - err = scsi_internal_device_block_nowait(sdev); + err = __scsi_internal_device_block_nowait(sdev); if (err == 0) - blk_mq_quiesce_queue(q); + blk_mq_quiesce_queue(sdev->request_queue); mutex_unlock(&sdev->state_mutex); return err; |