rbd: encapsulate new rbd id selection

Move the loop that finds a new unique rbd id to use into
its own helper function.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 19 insertions, 11 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index d8d052d42258..aaa19d8c3670 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -2149,6 +2149,23 @@ static int rbd_init_watch_dev(struct rbd_device *rbd_dev)
         return ret;
 }
 
+/* caller must hold ctl_mutex */
+static int rbd_id_get(void)
+{
+        struct list_head *tmp;
+        int new_id = 0;
+
+        list_for_each(tmp, &rbd_dev_list) {
+                struct rbd_device *rbd_dev;
+
+                rbd_dev = list_entry(tmp, struct rbd_device, node);
+                if (rbd_dev->id >= new_id)
+                        new_id = rbd_dev->id + 1;
+        }
+
+        return new_id;
+}
+
 static ssize_t rbd_add(struct bus_type *bus,
                        const char *buf,
                        size_t count)
@@ -2156,8 +2173,7 @@ static ssize_t rbd_add(struct bus_type *bus,
         struct ceph_osd_client *osdc;
         struct rbd_device *rbd_dev;
         ssize_t rc = -ENOMEM;
-        int irc, new_id = 0;
-        struct list_head *tmp;
+        int irc;
         char *mon_dev_name;
         char *options;
 
@@ -2187,15 +2203,7 @@ static ssize_t rbd_add(struct bus_type *bus,
         /* generate unique id: find highest unique id, add one */
         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 
-        list_for_each(tmp, &rbd_dev_list) {
-                struct rbd_device *rbd_dev;
-
-                rbd_dev = list_entry(tmp, struct rbd_device, node);
-                if (rbd_dev->id >= new_id)
-                        new_id = rbd_dev->id + 1;
-        }
-
-        rbd_dev->id = new_id;
+        rbd_dev->id = rbd_id_get();
 
         /* add to global list */
         list_add_tail(&rbd_dev->node, &rbd_dev_list);