def get_data_disk_size(vm_, swap, linode_id):
    '''
    Return the size of of the data disk in MB

    .. versionadded:: 2016.3.0
    '''
    disk_size = get_linode(kwargs={'linode_id': linode_id})['TOTALHD']
    root_disk_size = config.get_cloud_config_value(
        'disk_size', vm_, __opts__, default=disk_size - swap
    )
    return disk_size - root_disk_size - swap