diff --git a/core/storage/xen.py b/core/storage/xen.py
index cdc52355..d2e1ebde 100644
--- a/core/storage/xen.py
+++ b/core/storage/xen.py
@@ -65,31 +65,31 @@ class XenStorage(QubesVmStorage):
         self.volatile_img = os.path.join(vmdir, 'volatile.img')
 
     def root_dev_config(self):
-        if self.vm.is_template() and \
-                os.path.exists(os.path.join(self.vmdir, "root-cow.img")):
+        if self.vm.is_template() and self.rootcow_img:
             return self.format_disk_dev(
-                    "{dir}/root.img:{dir}/root-cow.img".format(
-                        dir=self.vmdir),
+                    "{root}:{rootcow}".format(
+                        root=self.root_img, rootcow=self.rootcow_img),
                     "block-origin", self.root_dev, True)
         elif self.vm.template and not self.vm.template.storage.rootcow_img:
             # HVM template-based VM - template doesn't have own
             # root-cow.img, only one device-mapper layer
             return self.format_disk_dev(
-                    "{tpldir}/root.img:{vmdir}/volatile.img".format(
-                        tpldir=self.vm.template.dir_path,
-                        vmdir=self.vmdir),
+                    "{root}:{volatile}".format(
+                        root=self.vm.template.storage.root_img,
+                        volatile=self.volatile_img),
                     "block-snapshot", self.root_dev, True)
         elif self.vm.template:
             # any other template-based VM - two device-mapper layers: one
             # in dom0 (here) from root+root-cow, and another one from
             # this+volatile.img
             return self.format_disk_dev(
-                    "{dir}/root.img:{dir}/root-cow.img".format(
-                        dir=self.vm.template.dir_path),
+                    "{root}:{rootcow}".format(
+                        root=self.root_img,
+                        rootcow=self.vm.template.storage.rootcow_img),
                     "block-snapshot", self.root_dev, False)
         else:
             return self.format_disk_dev(
-                    "{dir}/root.img".format(dir=self.vmdir),
+                    "{root}".format(root=self.root_img),
                     None, self.root_dev, True)
 
     def private_dev_config(self):