X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=block%2Fblk-mq-tag.h;h=9eb2cf4f01cb874706d64af87a01e94e0121f7e4;hb=90b0fc26d5dbe21c7a21668320b276af9b2281d7;hp=75893a34237d2eb2b4d07bd21a70cc35948c172a;hpb=473e0bc39bd5d2542e90edc622a65bd49206409d;p=firefly-linux-kernel-4.4.55.git

diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h
index 75893a34237d..9eb2cf4f01cb 100644
--- a/block/blk-mq-tag.h
+++ b/block/blk-mq-tag.h
@@ -89,4 +89,16 @@ static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
 	__blk_mq_tag_idle(hctx);
 }
 
+/*
+ * This helper should only be used for flush request to share tag
+ * with the request cloned from, and both the two requests can't be
+ * in flight at the same time. The caller has to make sure the tag
+ * can't be freed.
+ */
+static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx,
+		unsigned int tag, struct request *rq)
+{
+	hctx->tags->rqs[tag] = rq;
+}
+
 #endif