Support unprivileged ephemeral container using aufs

As the commit 31a882e, an unprivileged container can use aufs.
This patch removes the check for unpriv aufs, and change the path of
xino file as an unprivileged user can mount aufs.

Signed-off-by: KATOH Yasufumi <karma@jazz.email.ne.jp>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>

src/lxc/lxc-start-ephemeral.in

@@ -117,12 +117,6 @@ parser.add_argument("--version", action="version", version=lxc.version)
 
 args = parser.parse_args()
 
-# Basic requirements check
-## We only support privileged containers for now
-if os.geteuid() != 0 and args.union_type != "overlayfs":
-    parser.error(_("Unprivileged containers may only use "
-                   "overlayfs at this time."))
-
 ## Check that -d and CMD aren't used at the same time
 if args.command and args.daemon:
     parser.error(_("You can't use -d and a command at the same time."))
@@ -230,7 +224,7 @@ LXC_NAME="%s"
                          entry[0],
                          entry[1]))
         elif args.union_type == "aufs":
-            xino_path = "%s/lxc/aufs.xino" % get_rundir()
+            xino_path = "/dev/shm/aufs.xino"
             if not os.path.exists(os.path.basename(xino_path)):
                 os.makedirs(os.path.basename(xino_path))