Re: [RFC] [PATCH] helper function for retrieving scsi_cmd given host based block layer tag

David C Somayajulu
2006-10-03T22:27:54Z

On Tue, 2006-10-03 at 21:10 +0200, Jens Axboe wrote:
> The content and indentation looks good, but it doesn't apply to the
> current tree. Care to rediff it?
Here it is. Thanks.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: David Somayajulu <david.somayajulu@qlogic.com>
Date: Tue Oct 3 14:52:51 2006 -0700

---

block/ll_rw_blk.c | 7 +------
include/linux/blkdev.h | 8 ++++++++
include/scsi/scsi_tcq.h | 20 ++++++++++++++++++++
3 files changed, 29 insertions(+), 6 deletions(-)

fd6b37cdcd6db09207461f56eeebd377bab49d01
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 83425fb..c847e17 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -840,12 +840,7 @@ EXPORT_SYMBOL(blk_queue_dma_alignment);
**/
struct request *blk_queue_find_tag(request_queue_t *q, int tag)
{
- struct blk_queue_tag *bqt = q->queue_tags;
-
- if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
- return NULL;
-
- return bqt->tag_index[tag];
+ return blk_map_queue_find_tag(q->queue_tags, tag);
}

EXPORT_SYMBOL(blk_queue_find_tag);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 1d79b8d..26f7856 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -769,6 +769,14 @@ extern struct blk_queue_tag *blk_init_ta
extern void blk_free_tags(struct blk_queue_tag *);
extern void blk_congestion_end(int rw);

+static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
+ int tag)
+{
+ if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
+ return NULL;
+ return bqt->tag_index[tag];
+}
+
extern void blk_rq_bio_prep(request_queue_t *, struct request *, struct bio *);
extern int blkdev_issue_flush(struct block_device *, sector_t *);

diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h
index c247a28..cf4c219 100644
--- a/include/scsi/scsi_tcq.h
+++ b/include/scsi/scsi_tcq.h
@@ -144,5 +144,25 @@ static inline int scsi_init_shared_tag_m
return shost->bqt ? 0 : -ENOMEM;
}

+/**
+ * scsi_host_find_tag - find the tagged command by host
+ * @shost: pointer to scsi_host
+ * @tag: tag of the scsi_cmnd
+ *
+ * Notes:
+ * Only works with tags allocated by the generic blk layer.
+ **/
+static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost,
+ int tag)
+{
+ struct request *req;
+
+ if (tag != SCSI_NO_TAG) {
+ req = blk_map_queue_find_tag(shost->bqt, tag);
+ return req ? (struct scsi_cmnd *)req->special : NULL;
+ }
+ return NULL;
+}
+
#endif /* CONFIG_BLOCK */
#endif /* _SCSI_SCSI_TCQ_H */
--