def _open_volume(self, passphrase, **kwargs):
        LOG.debug("opening encrypted volume %s", self.dev_path)
        utils.execute('cryptsetup', 'luksOpen', '--key-file=-',
                      self.dev_path, self.dev_name, process_input=passphrase,
                      run_as_root=True, check_exit_code=True)
Opens the LUKS partition on the volume using the specified
dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/volume/encryptors/luks.py/LuksEncryptor._open_volume