static int posix_aio_init(void) { struct sigaction act; PosixAioState *s; int fds[2]; struct qemu_paioinit ai; if (posix_aio_state) return 0; s = qemu_malloc(sizeof(PosixAioState)); sigfillset(&act.sa_mask); act.sa_flags = 0; /* do not restart syscalls to interrupt select() */ act.sa_handler = aio_signal_handler; sigaction(SIGUSR2, &act, NULL); s->first_aio = NULL; if (pipe(fds) == -1) { fprintf(stderr, "failed to create pipe\n"); return -errno; } s->rfd = fds[0]; s->wfd = fds[1]; fcntl(s->rfd, F_SETFL, O_NONBLOCK); fcntl(s->wfd, F_SETFL, O_NONBLOCK); qemu_aio_set_fd_handler(s->rfd, posix_aio_read, NULL, posix_aio_flush, s); memset(&ai, 0, sizeof(ai)); ai.aio_threads = 64; ai.aio_num = 64; qemu_paio_init(&ai); posix_aio_state = s; return 0; }