ceph: provide seperate {inode,file}_operations for snapdir

remove all unsupported operations from {inode,file}_operations.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index f61a741..d0fe2f4 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -82,8 +82,8 @@
 	inode->i_mode = parent->i_mode;
 	inode->i_uid = parent->i_uid;
 	inode->i_gid = parent->i_gid;
-	inode->i_op = &ceph_dir_iops;
-	inode->i_fop = &ceph_dir_fops;
+	inode->i_op = &ceph_snapdir_iops;
+	inode->i_fop = &ceph_snapdir_fops;
 	ci->i_snap_caps = CEPH_CAP_PIN; /* so we can open */
 	ci->i_rbytes = 0;
 	return inode;