diff --git a/Documentation/filesystems/ceph.txt b/Documentation/filesystems/ceph.txt
index d6030aa33376..f5306ee40ea9 100644
--- a/Documentation/filesystems/ceph.txt
+++ b/Documentation/filesystems/ceph.txt
@@ -98,6 +98,10 @@ Mount Options
 	size.
 
   rsize=X
+	Specify the maximum read size in bytes.  By default there is no
+	maximum.
+
+  rasize=X
 	Specify the maximum readahead.
 
   mount_timeout=X