diff --git a/docs/storage-drivers/filesystem.md b/docs/storage-drivers/filesystem.md
index d7052df1..ab50f0f6 100644
--- a/docs/storage-drivers/filesystem.md
+++ b/docs/storage-drivers/filesystem.md
@@ -10,7 +10,9 @@ An implementation of the `storagedriver.StorageDriver` interface which uses the
 
 * `rootdirectory`: (optional) The absolute path to a root directory tree in which
 to store all registry files. The registry stores all its data here so make sure
-there is adequate space available. Defaults to `/var/lib/registry`.
+there is adequate space available. Defaults to `/var/lib/registry`. If the directory
+does not exist, it will be created honoring [`umask`](http://man7.org/linux/man-pages/man2/umask.2.html)
+bits. If `umask` bits are not set, the resulting permission will be `0777`.
 * `maxthreads`: (optional) The maximum number of simultaneous blocking filesystem
 operations permitted within the registry. Each operation spawns a new thread and
 may cause thread exhaustion issues if many are done in parallel. Defaults to