GPFS: Handle unsupported operations with an exception

This patch adds a support to fail the unsupported CG operations
for GPFS driver with GPFSDriverUnsupportedOperation exception.

Change-Id: Icd5a693ac75eca0f55cc3ecb014feb192e9e84d7
Closes-bug: #1691526

cinder/exception.py

@@ -1389,3 +1389,8 @@ class ErrorInHyperScaleVersion(VolumeDriverException):
 
 class ErrorInParsingArguments(VolumeDriverException):
     message = _("Error in parsing message arguments : Invalid Payload")
+
+
+# GPFS driver
+class GPFSDriverUnsupportedOperation(VolumeBackendAPIException):
+    message = _("GPFS driver unsupported operation: %(msg)s")

cinder/tests/unit/volume/drivers/test_gpfs.py

@@ -1647,6 +1647,19 @@ class GPFSDriverTestCase(test.TestCase):
         self.assertRaises(exception.VolumeBackendAPIException,
                           self.driver.delete_consistencygroup, ctxt, group, [])
 
+    def test_update_consistencygroup(self):
+        ctxt = self.context
+        group = self._fake_group()
+        self.assertRaises(exception.GPFSDriverUnsupportedOperation,
+                          self.driver.update_consistencygroup, ctxt, group)
+
+    def test_create_consisgroup_from_src(self):
+        ctxt = self.context
+        group = self._fake_group()
+        self.assertRaises(exception.GPFSDriverUnsupportedOperation,
+                          self.driver.create_consistencygroup_from_src,
+                          ctxt, group, [])
+
     @mock.patch('cinder.volume.drivers.ibm.gpfs.GPFSDriver.create_snapshot')
     def test_create_cgsnapshot(self, mock_create_snap):
         ctxt = self.context

cinder/volume/drivers/ibm/gpfs.py

@@ -1240,6 +1240,20 @@ class GPFSDriver(driver.CloneableImageVD,
 
         return model_update, snapshots_model_update
 
+    def update_consistencygroup(self, context, group,
+                                add_volumes=None, remove_volumes=None):
+        msg = _('Updating a consistency group is not supported.')
+        LOG.error(msg)
+        raise exception.GPFSDriverUnsupportedOperation(msg=msg)
+
+    def create_consistencygroup_from_src(self, context, group, volumes,
+                                         cgsnapshot=None, snapshots=None,
+                                         source_cg=None, source_vols=None):
+        msg = _('Creating a consistency group from any source consistency'
+                'group or consistency group snapshot is not supported.')
+        LOG.error(msg)
+        raise exception.GPFSDriverUnsupportedOperation(msg=msg)
+
 
 @interface.volumedriver
 class GPFSRemoteDriver(GPFSDriver, san.SanDriver):