[PATCH 02/24] scsi: add scsi_{get,put}_reserved_cmd()

[Hannes Reinecke]

Add helper functions to retrieve SCSI commands from the reserved
tag pool.

Signed-off-by: Hannes Reinecke <h...@suse.com>
---
 include/scsi/scsi_tcq.h | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h
index 6053d46e794e..227f3bd4e974 100644
--- a/include/scsi/scsi_tcq.h
+++ b/include/scsi/scsi_tcq.h
@@ -39,5 +39,27 @@ static inline struct scsi_cmnd *scsi_host_find_tag(struct 
Scsi_Host *shost,
        return blk_mq_rq_to_pdu(req);
 }
 
+static inline struct scsi_cmnd *scsi_get_reserved_cmd(struct scsi_device *sdev)
+{
+       struct request *rq;
+       struct scsi_cmnd *scmd;
+
+       rq = blk_mq_alloc_request(sdev->request_queue,
+                                 REQ_OP_SCSI_OUT | REQ_NOWAIT,
+                                 BLK_MQ_REQ_RESERVED);
+       if (IS_ERR(rq))
+               return NULL;
+       scmd = blk_mq_rq_to_pdu(rq);
+       scmd->request = rq;
+       return scmd;
+}
+
+static inline void scsi_put_reserved_cmd(struct scsi_cmnd *scmd)
+{
+       struct request *rq = blk_mq_rq_from_pdu(scmd);
+
+       blk_mq_free_request(rq);
+}
+
 #endif /* CONFIG_BLOCK */
 #endif /* _SCSI_SCSI_TCQ_H */
-- 
2.16.4