rbd: encapsulate probing for parent devices

Encapsulate the code that probes for an rbd device's parent images
into a new function, rbd_dev_probe_parent().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index b6024a2..c80fc1a 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -4702,11 +4702,49 @@ out_err:
        return ret;
 }
 
-static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
+static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
 {
        struct rbd_device *parent = NULL;
-       struct rbd_spec *parent_spec = NULL;
-       struct rbd_client *rbdc = NULL;
+       struct rbd_spec *parent_spec;
+       struct rbd_client *rbdc;
+       int ret;
+
+       if (!rbd_dev->parent_spec)
+               return 0;
+       /*
+        * We need to pass a reference to the client and the parent
+        * spec when creating the parent rbd_dev.  Images related by
+        * parent/child relationships always share both.
+        */
+       parent_spec = rbd_spec_get(rbd_dev->parent_spec);
+       rbdc = __rbd_get_client(rbd_dev->rbd_client);
+
+       ret = -ENOMEM;
+       parent = rbd_dev_create(rbdc, parent_spec);
+       if (!parent)
+               goto out_err;
+
+       ret = rbd_dev_image_probe(parent);
+       if (ret < 0)
+               goto out_err;
+       rbd_dev->parent = parent;
+
+       return 0;
+out_err:
+       if (parent) {
+               rbd_spec_put(rbd_dev->parent_spec);
+               kfree(rbd_dev->header_name);
+               rbd_dev_destroy(parent);
+       } else {
+               rbd_put_client(rbdc);
+               rbd_spec_put(parent_spec);
+       }
+
+       return ret;
+}
+
+static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
+{
        int ret;
 
        /* no need to lock here, as rbd_dev is not registered yet */
@@ -4747,34 +4785,9 @@ static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
        if (ret)
                goto err_out_disk;
 
-       /*
-        * At this point cleanup in the event of an error is the job
-        * of the sysfs code (initiated by rbd_bus_del_dev()).
-        */
-       /* Probe the parent if there is one */
-
-       if (rbd_dev->parent_spec) {
-               /*
-                * We need to pass a reference to the client and the
-                * parent spec when creating the parent rbd_dev.
-                * Images related by parent/child relationships
-                * always share both.
-                */
-               parent_spec = rbd_spec_get(rbd_dev->parent_spec);
-               rbdc = __rbd_get_client(rbd_dev->rbd_client);
-
-               parent = rbd_dev_create(rbdc, parent_spec);
-               if (!parent) {
-                       ret = -ENOMEM;
-                       goto err_out_spec;
-               }
-               rbdc = NULL;            /* parent now owns reference */
-               parent_spec = NULL;     /* parent now owns reference */
-               ret = rbd_dev_image_probe(parent);
-               if (ret < 0)
-                       goto err_out_parent;
-               rbd_dev->parent = parent;
-       }
+       ret = rbd_dev_probe_parent(rbd_dev);
+       if (ret)
+               goto err_out_bus;
 
        ret = rbd_dev_header_watch_sync(rbd_dev, 1);
        if (ret)
@@ -4791,13 +4804,6 @@ static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
 
        return ret;
 
-err_out_parent:
-       rbd_spec_put(rbd_dev->parent_spec);
-       kfree(rbd_dev->header_name);
-       rbd_dev_destroy(parent);
-err_out_spec:
-       rbd_spec_put(parent_spec);
-       rbd_put_client(rbdc);
 err_out_bus:
        /* this will also clean up rest of rbd_dev stuff */