'Extend an existing volume.'

def extend_volume(self, volume, new_size):

    sfaccount = self._get_sfaccount(volume['project_id'])
    params = {'accountID': sfaccount['accountID']}
    sf_vol = self._get_sf_volume(volume['id'], params)
    if (sf_vol is None):
        LOG.error('Volume    ID    %s    was    not    found    on    the    SolidFire    Cluster    while    attempting    extend_volume    operation!', volume['id'])
        raise exception.VolumeNotFound(volume_id=volume['id'])
    params = {'volumeID': sf_vol['volumeID'], 'totalSize': int((new_size * units.Gi))}
    self._issue_api_request('ModifyVolume', params, version='5.0')
