LXR linux/include/scsi/scsi

   1#ifndef _SCSI_SCSI_TCQ_H
   2#define _SCSI_SCSI_TCQ_H
   3
   4#include <linux/blkdev.h>
   5#include <scsi/scsi_cmnd.h>
   6#include <scsi/scsi_device.h>
   7#include <scsi/scsi_host.h>
   8
   9#define SCSI_NO_TAG     (-1)    /* identify no tag in use */
  10
  11
  12#ifdef CONFIG_BLOCK
  13/**
  14 * scsi_host_find_tag - find the tagged command by host
  15 * @shost:      pointer to scsi_host
  16 * @tag:        tag
  17 *
  18 * Note: for devices using multiple hardware queues tag must have been
  19 * generated by blk_mq_unique_tag().
  20 **/
  21static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost,
  22                int tag)
  23{
  24        struct request *req = NULL;
  25
  26        if (tag == SCSI_NO_TAG)
  27                return NULL;
  28
  29        if (shost_use_blk_mq(shost)) {
  30                u16 hwq = blk_mq_unique_tag_to_hwq(tag);
  31
  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        } else {
  37                req = blk_map_queue_find_tag(shost->bqt, tag);
  38        }
  39
  40        if (!req)
  41                return NULL;
  42        return req->special;
  43}
  44
  45#endif /* CONFIG_BLOCK */
  46#endif /* _SCSI_SCSI_TCQ_H */
  47