Avoid that it can take 200 ms too long to wait for requests to
finish. Note: blk_mq_freeze_queue() uses a wait queue to wait
for ongoing requests to finish.
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Cc: Ming Lei <ming.lei@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxxx>
Cc: Johannes Thumshirn <jthumshirn@xxxxxxx>
---
drivers/scsi/scsi_lib.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 62f905b22821..e0bef5c9dd14 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2927,21 +2927,25 @@ static void scsi_wait_for_queuecommand(struct scsi_device *sdev)
int
scsi_device_quiesce(struct scsi_device *sdev)
{
+ struct request_queue *q = sdev->request_queue;
+ bool freeze;
int err;
mutex_lock(&sdev->state_mutex);
+ /*
+ * Do not attempt to freeze the queue of an already quiesced device
+ * because that could result in a deadlock.
+ */
+ freeze = sdev->sdev_state == SDEV_RUNNING;
+ if (freeze)
+ blk_mq_freeze_queue(q);
err = scsi_device_set_state(sdev, SDEV_QUIESCE);
mutex_unlock(&sdev->state_mutex);
- if (err)
- return err;
+ if (freeze)
+ blk_mq_unfreeze_queue(q);
- scsi_run_queue(sdev->request_queue);
- while (atomic_read(&sdev->device_busy)) {
- msleep_interruptible(200);
- scsi_run_queue(sdev->request_queue);
- }
- return 0;
+ return err;
}
EXPORT_SYMBOL(scsi_device_quiesce);
--
2.14.1
