[PATCH 3/5] null_blk: create a helper for mem-backed ops

[Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>]

This patch creates a helper for handling requests when null_blk is
memory backed in the null_handle_cmd().

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>
---
 drivers/block/null_blk_main.c | 35 +++++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c
index 80c30bcf024f..e75d187c7393 100644
--- a/drivers/block/null_blk_main.c
+++ b/drivers/block/null_blk_main.c
@@ -1194,10 +1194,29 @@ static inline blk_status_t null_handle_badblocks(struct nullb_cmd *cmd)
 	return sts;
 }
 
+static inline int nullb_handle_memory_backed(struct nullb_cmd *cmd)
+{
+	struct nullb_device *dev = cmd->nq->dev;
+
+	if (!dev->memory_backed)
+		return 0;
+
+	if (dev->queue_mode == NULL_Q_BIO) {
+		if (bio_op(cmd->bio) == REQ_OP_FLUSH)
+			return null_handle_flush(dev->nullb);
+
+		return null_handle_bio(cmd);
+	}
+
+	if (req_op(cmd->rq) == REQ_OP_FLUSH)
+		return null_handle_flush(dev->nullb);
+
+	return null_handle_rq(cmd);
+}
+
 static blk_status_t null_handle_cmd(struct nullb_cmd *cmd)
 {
 	struct nullb_device *dev = cmd->nq->dev;
-	struct nullb *nullb = dev->nullb;
 	blk_status_t sts;
 	int err = 0;
 
@@ -1209,19 +1228,7 @@ static blk_status_t null_handle_cmd(struct nullb_cmd *cmd)
 	if (sts != BLK_STS_OK)
 		goto out;
 
-	if (dev->memory_backed) {
-		if (dev->queue_mode == NULL_Q_BIO) {
-			if (bio_op(cmd->bio) == REQ_OP_FLUSH)
-				err = null_handle_flush(nullb);
-			else
-				err = null_handle_bio(cmd);
-		} else {
-			if (req_op(cmd->rq) == REQ_OP_FLUSH)
-				err = null_handle_flush(nullb);
-			else
-				err = null_handle_rq(cmd);
-		}
-	}
+	err = nullb_handle_memory_backed(cmd);
 	cmd->error = errno_to_blk_status(err);
 
 	if (!cmd->error && dev->zoned) {
-- 
2.21.0