Merge "Huawei: Check the real size before extend volume"

cinder/tests/unit/test_huawei_drivers.py

@@ -2006,8 +2006,25 @@ class HuaweiISCSIDriverTestCase(test.TestCase):
         data = self.driver.get_volume_stats()
         self.assertEqual('2.0.5', data['driver_version'])
 
-    def test_extend_volume(self):
+    @mock.patch.object(rest_client.RestClient, 'get_lun_info',
+                       return_value={"CAPACITY": 6291456})
+    @mock.patch.object(rest_client.RestClient, 'extend_lun')
+    def test_extend_volume_size_equal(self, mock_extend, mock_lun_info):
         self.driver.extend_volume(test_volume, 3)
+        self.assertEqual(0, mock_extend.call_count)
+
+    @mock.patch.object(rest_client.RestClient, 'get_lun_info',
+                       return_value={"CAPACITY": 5291456})
+    @mock.patch.object(rest_client.RestClient, 'extend_lun')
+    def test_extend_volume_success(self, mock_extend, mock_lun_info):
+        self.driver.extend_volume(test_volume, 3)
+        self.assertEqual(1, mock_extend.call_count)
+
+    @mock.patch.object(rest_client.RestClient, 'get_lun_info',
+                       return_value={"CAPACITY": 7291456})
+    def test_extend_volume_fail(self, mock_lun_info):
+        self.assertRaises(exception.VolumeBackendAPIException,
+                          self.driver.extend_volume, test_volume, 3)
 
     def test_login_fail(self):
         self.driver.client.test_fail = True

cinder/volume/drivers/huawei/huawei_driver.py

@@ -691,8 +691,26 @@ class HuaweiBaseDriver(driver.VolumeDriver):
             LOG.error(msg)
             raise exception.VolumeBackendAPIException(data=msg)
 
-        old_size = huawei_utils.get_volume_size(volume)
+        lun_info = self.client.get_lun_info(lun_id)
+        old_size = int(lun_info.get('CAPACITY'))
+
         new_size = int(new_size) * units.Gi / 512
+
+        if new_size == old_size:
+            LOG.info(_LI("New size is equal to the real size from backend"
+                         " storage, no need to extend."
+                         " realsize: %(oldsize)s, newsize: %(newsize)s."),
+                     {'oldsize': old_size,
+                      'newsize': new_size})
+            return
+        if new_size < old_size:
+            msg = (_("New size should be bigger than the real size from "
+                     "backend storage."
+                     " realsize: %(oldsize)s, newsize: %(newsize)s."),
+                   {'oldsize': old_size,
+                    'newsize': new_size})
+            LOG.error(msg)
+            raise exception.VolumeBackendAPIException(data=msg)
         volume_name = huawei_utils.encode_name(volume['id'])
 
         LOG.info(_LI(