nsfs: add ioctl to get a parent namespace
Pid and user namepaces are hierarchical. There is no way to discover
parent-child relationships.
In a future we will use this interface to dump and restore nested
namespaces.
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 0ef683a..a58a219 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -1034,6 +1034,7 @@
.put = userns_put,
.install = userns_install,
.owner = userns_owner,
+ .get_parent = ns_get_owner,
};
static __init int user_namespaces_init(void)