1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _SCSI_SCSI_TCQ_H
3#define _SCSI_SCSI_TCQ_H
4
5#include <linux/blkdev.h>
6#include <scsi/scsi_cmnd.h>
7#include <scsi/scsi_device.h>
8#include <scsi/scsi_host.h>
9
10#define SCSI_NO_TAG (-1) /* identify no tag in use */
11
12
13#ifdef CONFIG_BLOCK
14/**
15 * scsi_host_find_tag - find the tagged command by host
16 * @shost: pointer to scsi_host
17 * @tag: tag
18 *
19 * Note: for devices using multiple hardware queues tag must have been
20 * generated by blk_mq_unique_tag().
21 **/
22static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost,
23 int tag)
24{
25 struct request *req = NULL;
26 u16 hwq;
27
28 if (tag == SCSI_NO_TAG)
29 return NULL;
30
31 hwq = blk_mq_unique_tag_to_hwq(unique_tag: tag);
32 if (hwq < shost->tag_set.nr_hw_queues) {
33 req = blk_mq_tag_to_rq(tags: shost->tag_set.tags[hwq],
34 tag: blk_mq_unique_tag_to_tag(unique_tag: tag));
35 }
36
37 if (!req || !blk_mq_request_started(rq: req))
38 return NULL;
39 return blk_mq_rq_to_pdu(rq: req);
40}
41
42#endif /* CONFIG_BLOCK */
43#endif /* _SCSI_SCSI_TCQ_H */
44