rbd: introduce rados block device (rbd), based on libceph

The rados block device (rbd), based on osdblk, creates a block device
that is backed by objects stored in the Ceph distributed object storage
cluster.  Each device consists of a single metadata object and data
striped over many data objects.

The rbd driver supports read-only snapshots.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/net/ceph/debugfs.c b/net/ceph/debugfs.c
index 33d0499..27d4ea31 100644
--- a/net/ceph/debugfs.c
+++ b/net/ceph/debugfs.c
@@ -252,8 +252,7 @@
 {
 }
 
-int ceph_debugfs_client_init(struct ceph_client *client,
-			     int (*module_debugfs_init)(struct ceph_client *))
+int ceph_debugfs_client_init(struct ceph_client *client)
 {
 	return 0;
 }