rbd: introduce rbd_dev_header_info()

A wrapper around rbd_dev_v{1,2}_header_info() to reduce duplication.
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Alex Elder <elder@linaro.org>

drivers/block/rbd.c

@@ -514,7 +514,7 @@ static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
 
 static int rbd_dev_refresh(struct rbd_device *rbd_dev);
 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
-static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev);
+static int rbd_dev_header_info(struct rbd_device *rbd_dev);
 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
 					u64 snap_id);
 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
@@ -3506,13 +3506,10 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev)
 	u64 mapping_size;
 	int ret;
 
-	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
 	down_write(&rbd_dev->header_rwsem);
 	mapping_size = rbd_dev->mapping.size;
-	if (rbd_dev->image_format == 1)
-		ret = rbd_dev_v1_header_info(rbd_dev);
-	else
-		ret = rbd_dev_v2_header_info(rbd_dev);
+
+	ret = rbd_dev_header_info(rbd_dev);
 
 	/* If it's a mapped snapshot, validate its EXISTS flag */
 
@@ -4501,6 +4498,16 @@ static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
 	return ret;
 }
 
+static int rbd_dev_header_info(struct rbd_device *rbd_dev)
+{
+	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+
+	if (rbd_dev->image_format == 1)
+		return rbd_dev_v1_header_info(rbd_dev);
+
+	return rbd_dev_v2_header_info(rbd_dev);
+}
+
 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
 {
 	struct device *dev;
@@ -5149,10 +5156,7 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping)
 			goto out_header_name;
 	}
 
-	if (rbd_dev->image_format == 1)
-		ret = rbd_dev_v1_header_info(rbd_dev);
-	else
-		ret = rbd_dev_v2_header_info(rbd_dev);
+	ret = rbd_dev_header_info(rbd_dev);
 	if (ret)
 		goto err_out_watch;