'Returns a BaseDiskFile instance for an object based on the object\'s
partition, path parts and policy.
:param device: name of target device
:param partition: partition on device in which the object lives
:param account: account name for the object
:param container: container name for the object
:param obj: object name for the object
:param policy: the StoragePolicy instance'

def get_diskfile(self, device, partition, account, container, obj, policy, **kwargs):

    dev_path = self.get_dev_path(device)
    if (not dev_path):
        raise DiskFileDeviceUnavailable()
    return self.diskfile_cls(self, dev_path, partition, account, container, obj, policy=policy, use_splice=self.use_splice, pipe_size=self.pipe_size, use_linkat=self.use_linkat, **kwargs)
