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(tag);
32	if (hwq < shost->tag_set.nr_hw_queues) {
33		req = blk_mq_tag_to_rq(shost->tag_set.tags[hwq],
34					blk_mq_unique_tag_to_tag(tag));
35	}
36
37	if (!req || !blk_mq_request_started(req))
38		return NULL;
39	return blk_mq_rq_to_pdu(req);
40}
41
42#endif /* CONFIG_BLOCK */
43#endif /* _SCSI_SCSI_TCQ_H */
44