On 5/5/21 2:45 AM, Bart Van Assche wrote:

On 5/3/21 8:03 AM, Hannes Reinecke wrote:

quoted

 struct scsi_cmnd *scsi_get_internal_cmd(struct scsi_device *sdev,
 	unsigned int op, blk_mq_req_flags_t flags)

@@ -2005,6 +2009,10 @@ struct scsi_cmnd *scsi_get_internal_cmd(struct scsi_device *sdev,
 
 	WARN_ON_ONCE(((op & REQ_OP_MASK) != REQ_OP_SCSI_IN) &&
 		     ((op & REQ_OP_MASK) != REQ_OP_SCSI_OUT));
+
+	if (sdev->host->nr_reserved_cmds)
+		flags |= BLK_MQ_REQ_RESERVED;
+
 	rq = blk_mq_alloc_request(sdev->request_queue, op, flags);
 	if (IS_ERR(rq))
 		return NULL;

Can the if-statement be removed such that scsi_get_internal_cmd() fails
if sdev->host->nr_reserved_cmds == 0? I'm concerned that otherwise it
will be very hard to determine which requests are internal and which
ones not from inside a blk_mq_tagset_busy_iter() callback.

Original idea was that one could use scsi_get_internal_cmd() even with
nr_reserved_cmds == 0, but you are right that this will probably just
lead to confusion.

Will be modifying it for the next round.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		        Kernel Storage Architect
hare@suse.de			               +49 911 74053 688
SUSE Software Solutions Germany GmbH, 90409 Nürnberg
GF: F. Imendörffer, HRB 36809 (AG Nürnberg)