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 static inline struct scsi_cmnd *scsi_mq_find_tag(struct Scsi_Host *shost, 14 int unique_tag) 15 { 16 u16 hwq = blk_mq_unique_tag_to_hwq(unique_tag); 17 struct request *req = NULL; 18 19 if (hwq < shost->tag_set.nr_hw_queues) 20 req = blk_mq_tag_to_rq(shost->tag_set.tags[hwq], 21 blk_mq_unique_tag_to_tag(unique_tag)); 22 return req ? (struct scsi_cmnd *)req->special : NULL; 23 } 24 25 /** 26 * scsi_find_tag - find a tagged command by device 27 * @SDpnt: pointer to the ScSI device 28 * @tag: tag generated by blk_mq_unique_tag() 29 * 30 * Notes: 31 * Only works with tags allocated by the generic blk layer. 32 **/ 33 static inline struct scsi_cmnd *scsi_find_tag(struct scsi_device *sdev, int tag) 34 { 35 struct request *req; 36 37 if (tag != SCSI_NO_TAG) { 38 if (shost_use_blk_mq(sdev->host)) 39 return scsi_mq_find_tag(sdev->host, tag); 40 41 req = blk_queue_find_tag(sdev->request_queue, tag); 42 return req ? (struct scsi_cmnd *)req->special : NULL; 43 } 44 45 /* single command, look in space */ 46 return sdev->current_cmnd; 47 } 48 49 50 /** 51 * scsi_init_shared_tag_map - create a shared tag map 52 * @shost: the host to share the tag map among all devices 53 * @depth: the total depth of the map 54 */ 55 static inline int scsi_init_shared_tag_map(struct Scsi_Host *shost, int depth) 56 { 57 /* 58 * We always have a shared tag map around when using blk-mq. 59 */ 60 if (shost_use_blk_mq(shost)) 61 return 0; 62 63 /* 64 * If the shared tag map isn't already initialized, do it now. 65 * This saves callers from having to check ->bqt when setting up 66 * devices on the shared host (for libata) 67 */ 68 if (!shost->bqt) { 69 shost->bqt = blk_init_tags(depth); 70 if (!shost->bqt) 71 return -ENOMEM; 72 } 73 74 return 0; 75 } 76 77 /** 78 * scsi_host_find_tag - find the tagged command by host 79 * @shost: pointer to scsi_host 80 * @tag: tag generated by blk_mq_unique_tag() 81 * 82 * Notes: 83 * Only works with tags allocated by the generic blk layer. 84 **/ 85 static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost, 86 int tag) 87 { 88 struct request *req; 89 90 if (tag != SCSI_NO_TAG) { 91 if (shost_use_blk_mq(shost)) 92 return scsi_mq_find_tag(shost, tag); 93 req = blk_map_queue_find_tag(shost->bqt, tag); 94 return req ? (struct scsi_cmnd *)req->special : NULL; 95 } 96 return NULL; 97 } 98 99 #endif /* CONFIG_BLOCK */ 100 #endif /* _SCSI_SCSI_TCQ_H */ 101