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scsi: core: use blk_mq_requeue_request in __scsi_queue_insert

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In scsi core, __scsi_queue_insert should just put request back on the
queue and retry using the same command as before. However, for blk-mq,
scsi_mq_requeue_cmd is employed here which will unprepare the
request. To align with the semantics of __scsi_queue_insert, use
blk_mq_requeue_request with kick_requeue_list == true and put the
reference of scsi_device.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Jianchao Wang 2018-03-03 09:54:09 +08:00 committed by Martin K. Petersen
parent 61b142afb2
commit 2f793a27d5
1 changed files with 13 additions and 1 deletions
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14
drivers/scsi/scsi_lib.c
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@ -191,7 +191,19 @@ static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy)
*/
cmd->result = 0;
if (q->mq_ops) {
scsi_mq_requeue_cmd(cmd);
/*
* Before a SCSI command is dispatched,
* get_device(&sdev->sdev_gendev) is called and the host,
* target and device busy counters are increased. Since
* requeuing a request causes these actions to be repeated and
* since scsi_device_unbusy() has already been called,
* put_device(&device->sdev_gendev) must still be called. Call
* put_device() after blk_mq_requeue_request() to avoid that
* removal of the SCSI device can start before requeueing has
* happened.
*/
blk_mq_requeue_request(cmd->request, true);
put_device(&device->sdev_gendev);
return;
}
spin_lock_irqsave(q->queue_lock, flags);