static inline ssize_t aio_ret(struct kiocb *req, ssize_t ret)
    {
            switch (ret) {
            case -EIOCBQUEUED:
                    return ret;
            case -ERESTARTSYS:
            case -ERESTARTNOINTR:
            case -ERESTARTNOHAND:
            case -ERESTART_RESTARTBLOCK:
                    /*
                     * There's no easy way to restart the
                     * syscall since other AIO's may be already running.
                     * Just fail this IO with EINTR.
                     */
                    ret = -EINTR;
                    /*FALLTHRU*/
            default:
                    aio_complete(req, ret, 0);
                    return 0;
            }
    }