Move volume xml config from QubesVM to Volume

qubes/storage/__init__.py

@@ -71,6 +71,9 @@ class Volume(object):
         self.size = size
         self.volume_type = volume_type
 
+    def __xml__(self):
+        return lxml.etree.Element('volume', **self.config)
+
     @property
     def config(self):
         ''' return config data for serialization to qubes.xml '''

qubes/vm/qubesvm.py

@@ -493,8 +493,7 @@ class QubesVM(qubes.vm.mix.net.NetVMMixin, qubes.vm.BaseVM):
         if hasattr(self, 'volumes'):
             volume_config_node = lxml.etree.Element('volume-config')
             for volume in self.volumes.values():
-                volume_node = lxml.etree.Element('volume', **volume.config)
-                volume_config_node.append(volume_node)
+                volume_config_node.append(volume.__xml__())
 
             element.append(volume_config_node)