Set libvirt device alias for volumes

This makes the libvirt driver set the libvirt device alias on disk
entries for volumes to the volume UUID. Note that libvirt requires
us to prefix the value with "ua-", which this does.

Related to blueprint libvirt-dev-alias

Change-Id: I2f1fe8d1c9d4ca502ec5aca41fd14465994a5305

Author: kk7ds

nova/tests/unit/virt/libvirt/volume/test_volume.py

@@ -338,6 +338,23 @@ def test_libvirt_volume_driver_discard_false(self):
         tree = conf.format_dom()
         self.assertIsNone(tree.find("driver[@discard]"))
 
+    def test_libvirt_volume_alias(self):
+        # Check that the name/alias gets set from the volume_id
+        libvirt_driver = volume.LibvirtVolumeDriver(self.fake_host)
+        connection_info = {
+            'driver_volume_type': 'fake',
+            'data': {
+                'device_path': '/foo',
+                'volume_id': str(uuids.volume),
+            },
+            'serial': 'fake_serial',
+        }
+
+        conf = libvirt_driver.get_config(connection_info, self.disk_info)
+        tree = conf.format_dom()
+        self.assertEqual('ua-%s' % uuids.volume,
+                         tree.find("alias").get('name'))
+
     def test_libvirt_volume_driver_encryption(self):
         fake_secret = FakeSecret()
         fake_host = mock.Mock(spec=host.Host)

nova/virt/libvirt/volume/volume.py

@@ -118,6 +118,7 @@ def get_config(self, connection_info, disk_info):
             conf.shareable = True
 
         volume_id = driver_block_device.get_volume_id(connection_info)
+        conf.alias = vconfig.make_libvirt_device_alias(volume_id)
         volume_secret = None
         if volume_id:
             volume_secret = self.host.find_secret('volume', volume_id)