include/scsi/scsi_tcq.h

   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  **/
  22 static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost,
  23                 int tag)
  24 {
  25         struct request *req = NULL;
  26
  27         if (tag == SCSI_NO_TAG)
  28                 return NULL;
  29
  30         if (shost_use_blk_mq(shost)) {
  31                 u16 hwq = blk_mq_unique_tag_to_hwq(tag);
  32
  33                 if (hwq < shost->tag_set.nr_hw_queues) {
  34                         req = blk_mq_tag_to_rq(shost->tag_set.tags[hwq],
  35                                 blk_mq_unique_tag_to_tag(tag));
  36                 }
  37         } else {
  38                 req = blk_map_queue_find_tag(shost->bqt, tag);
  39         }
  40
  41         if (!req)
  42                 return NULL;
  43         return blk_mq_rq_to_pdu(req);
  44 }
  45
  46 #endif /* CONFIG_BLOCK */
  47 #endif /* _SCSI_SCSI_TCQ_H */