[PATCH 3/5] rbd: define rbd_dev_unparent()

[Alex Elder <elder@inktank.com>]

Define rbd_dev_unparent() to encapsulate cleaning up parent data
structures from a layered rbd image.

Signed-off-by: Alex Elder <elder@inktank.com>
---
 drivers/block/rbd.c |   22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index ac3f4e7..607c536 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1835,6 +1835,17 @@ static void rbd_obj_request_destroy(struct kref
*kref)
 	kmem_cache_free(rbd_obj_request_cache, obj_request);
 }

+/* It's OK to call this for a device with no parent */
+
+static void rbd_spec_put(struct rbd_spec *spec);
+static void rbd_dev_unparent(struct rbd_device *rbd_dev)
+{
+	rbd_dev_remove_parent(rbd_dev);
+	rbd_spec_put(rbd_dev->parent_spec);
+	rbd_dev->parent_spec = NULL;
+	rbd_dev->parent_overlap = 0;
+}
+
 /*
  * Caller is responsible for filling in the list of object requests
  * that comprises the image request, and the Linux request pointer
@@ -4062,9 +4073,7 @@ out_err:
 	rbd_dev->mapping.size = 0;
 	rbd_dev->header.image_size = 0;
 	rbd_dev->header.obj_order = 0;
-	rbd_dev->parent_overlap = 0;
-	rbd_spec_put(rbd_dev->parent_spec);
-	rbd_dev->parent_spec = NULL;
+	rbd_dev_unparent(rbd_dev);
 	rbd_dev->header.stripe_count = 0;
 	rbd_dev->header.stripe_unit = 0;
 	rbd_dev->header.features = 0;
@@ -4492,10 +4501,7 @@ static void rbd_dev_unprobe(struct rbd_device
*rbd_dev)
 {
 	struct rbd_image_header	*header;

-	rbd_dev_remove_parent(rbd_dev);
-	rbd_spec_put(rbd_dev->parent_spec);
-	rbd_dev->parent_spec = NULL;
-	rbd_dev->parent_overlap = 0;
+	rbd_dev_unparent(rbd_dev);

 	/* Free dynamic fields from the header, then zero it out */

@@ -4571,7 +4577,7 @@ static int rbd_dev_probe_parent(struct rbd_device
*rbd_dev)
 	return 0;
 out_err:
 	if (parent) {
-		rbd_spec_put(rbd_dev->parent_spec);
+		rbd_dev_unparent(rbd_dev);
 		kfree(rbd_dev->header_name);
 		rbd_dev_destroy(parent);
 	} else {
-- 
1.7.9.5