blk-mq: add blk_mq_requeue_request
This allows to requeue a request that has been accepted by ->queue_rq
earlier. This is needed by the SCSI layer in various error conditions.
The existing internal blk_mq_requeue_request is renamed to
__blk_mq_requeue_request as it is a lower level building block for this
funtionality.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 543bbc0..ee225cc 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -400,7 +400,7 @@
rq->cmd_flags |= REQ_END;
}
-static void blk_mq_requeue_request(struct request *rq)
+static void __blk_mq_requeue_request(struct request *rq)
{
struct request_queue *q = rq->q;
@@ -413,6 +413,20 @@
rq->nr_phys_segments--;
}
+void blk_mq_requeue_request(struct request *rq)
+{
+ struct request_queue *q = rq->q;
+
+ __blk_mq_requeue_request(rq);
+ blk_clear_rq_complete(rq);
+
+ trace_block_rq_requeue(q, rq);
+
+ BUG_ON(blk_queued_rq(rq));
+ blk_mq_insert_request(rq, true, true, false);
+}
+EXPORT_SYMBOL(blk_mq_requeue_request);
+
struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag)
{
return tags->rqs[tag];
@@ -602,7 +616,7 @@
* time
*/
list_add(&rq->queuelist, &rq_list);
- blk_mq_requeue_request(rq);
+ __blk_mq_requeue_request(rq);
break;
default:
pr_err("blk-mq: bad return on queue: %d\n", ret);
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 391377e..ab469d5 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -153,6 +153,8 @@
void blk_mq_end_io(struct request *rq, int error);
void __blk_mq_end_io(struct request *rq, int error);
+void blk_mq_requeue_request(struct request *rq);
+
void blk_mq_complete_request(struct request *rq);
void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx);