'clone source volume which should be smaller than target volume.'

def test_create_cloned_volume3(self):

    self.driver = FakeDS8KProxy(self.storage_info, self.logger, self.exception, self)
    self.driver.setup(self.ctxt)
    vol_type = volume_types.create(self.ctxt, 'VOL_TYPE', {})
    location = six.text_type({'vol_hex_id': TEST_VOLUME_ID})
    src_vol = self._create_volume(volume_type_id=vol_type.id, provider_location=location, size=2)
    location = six.text_type({'vol_hex_id': None})
    tgt_vol = self._create_volume(volume_type_id=vol_type.id, provider_location=location)
    self.assertRaises(exception.VolumeDriverException, self.driver.create_cloned_volume, tgt_vol, src_vol)
