summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--block/blk-mq.c16
-rw-r--r--include/linux/blk-mq.h10
2 files changed, 26 insertions, 0 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 2a1a653a8054..d8534107bb6f 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1259,6 +1259,14 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
if (!list_empty(list)) {
bool needs_restart;
+ /*
+ * If we didn't flush the entire list, we could have told
+ * the driver there was more coming, but that turned out to
+ * be a lie.
+ */
+ if (q->mq_ops->commit_rqs)
+ q->mq_ops->commit_rqs(hctx);
+
spin_lock(&hctx->lock);
list_splice_init(list, &hctx->dispatch);
spin_unlock(&hctx->lock);
@@ -1865,6 +1873,14 @@ void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
blk_mq_end_request(rq, ret);
}
}
+
+ /*
+ * If we didn't flush the entire list, we could have told
+ * the driver there was more coming, but that turned out to
+ * be a lie.
+ */
+ if (!list_empty(list) && hctx->queue->mq_ops->commit_rqs)
+ hctx->queue->mq_ops->commit_rqs(hctx);
}
static void blk_add_rq_to_plug(struct blk_plug *plug, struct request *rq)
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index b8de11e0603b..467f1dd21ccf 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -117,6 +117,7 @@ struct blk_mq_queue_data {
typedef blk_status_t (queue_rq_fn)(struct blk_mq_hw_ctx *,
const struct blk_mq_queue_data *);
+typedef void (commit_rqs_fn)(struct blk_mq_hw_ctx *);
/* takes rq->cmd_flags as input, returns a hardware type index */
typedef int (rq_flags_to_type_fn)(struct request_queue *, unsigned int);
typedef bool (get_budget_fn)(struct blk_mq_hw_ctx *);
@@ -145,6 +146,15 @@ struct blk_mq_ops {
queue_rq_fn *queue_rq;
/*
+ * If a driver uses bd->last to judge when to submit requests to
+ * hardware, it must define this function. In case of errors that
+ * make us stop issuing further requests, this hook serves the
+ * purpose of kicking the hardware (which the last request otherwise
+ * would have done).
+ */
+ commit_rqs_fn *commit_rqs;
+
+ /*
* Return a queue map type for the given request/bio flags
*/
rq_flags_to_type_fn *rq_flags_to_type;