Poll for completions if the request's hctx is a polling type.

Signed-off-by: Keith Busch <kbusch@kernel.org>
---
 block/blk-exec.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/block/blk-exec.c b/block/blk-exec.c
index beae70a0e5e5..b960ad187ba5 100644
--- a/block/blk-exec.c
+++ b/block/blk-exec.c

@@ -63,6 +63,11 @@ void blk_execute_rq_nowait(struct gendisk *bd_disk, struct request *rq,
 }
 EXPORT_SYMBOL_GPL(blk_execute_rq_nowait);

+static bool blk_rq_is_poll(struct request *rq)
+{
+       return rq->mq_hctx && rq->mq_hctx->type == HCTX_TYPE_POLL;
+}
+
 /**
  * blk_execute_rq - insert a request into queue for execution
  * @bd_disk:   matching gendisk

@@ -83,7 +88,12 @@ void blk_execute_rq(struct gendisk *bd_disk, struct request *rq, int at_head)

        /* Prevent hang_check timer from firing at us during very long I/O */
        hang_check = sysctl_hung_task_timeout_secs;
-       if (hang_check)
+       if (blk_rq_is_poll(rq)) {
+               do {
+                       blk_poll(rq->q, request_to_qc_t(rq->mq_hctx, rq), true);
+                       cond_resched();
+               } while (!completion_done(&wait));
+       } else if (hang_check)
                while (!wait_for_completion_io_timeout(&wait, hang_check * (HZ/2)));
        else
                wait_for_completion_io(&wait);
--