1 files changed, 11 insertions, 6 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 041f7b7fa0d6..211ef367345f 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -301,11 +301,12 @@ static struct request *blk_mq_get_request(struct request_queue *q,
         struct elevator_queue *e = q->elevator;
         struct request *rq;
         unsigned int tag;
+        struct blk_mq_ctx *local_ctx = NULL;
 
         blk_queue_enter_live(q);
         data->q = q;
         if (likely(!data->ctx))
-                data->ctx = blk_mq_get_ctx(q);
+                data->ctx = local_ctx = blk_mq_get_ctx(q);
         if (likely(!data->hctx))
                 data->hctx = blk_mq_map_queue(q, data->ctx->cpu);
         if (op & REQ_NOWAIT)
@@ -324,6 +325,10 @@ static struct request *blk_mq_get_request(struct request_queue *q,
 
         tag = blk_mq_get_tag(data);
         if (tag == BLK_MQ_TAG_FAIL) {
+                if (local_ctx) {
+                        blk_mq_put_ctx(local_ctx);
+                        data->ctx = NULL;
+                }
                 blk_queue_exit(q);
                 return NULL;
         }
@@ -356,12 +361,12 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
 
         rq = blk_mq_get_request(q, NULL, op, &alloc_data);
 
-        blk_mq_put_ctx(alloc_data.ctx);
-        blk_queue_exit(q);
-
         if (!rq)
                 return ERR_PTR(-EWOULDBLOCK);
 
+        blk_mq_put_ctx(alloc_data.ctx);
+        blk_queue_exit(q);
+
         rq->__data_len = 0;
         rq->__sector = (sector_t) -1;
         rq->bio = rq->biotail = NULL;
@@ -407,11 +412,11 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
 
         rq = blk_mq_get_request(q, NULL, op, &alloc_data);
 
-        blk_queue_exit(q);
-
         if (!rq)
                 return ERR_PTR(-EWOULDBLOCK);
 
+        blk_queue_exit(q);
+
         return rq;
 }
 EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx);