Beispiel #1
0
int main(int argc, char **argv)
{
    BlockBackend *blk;
    BlockDriverState *bs;
    off_t dev_offset = 0;
    uint32_t nbdflags = 0;
    bool disconnect = false;
    const char *bindto = "0.0.0.0";
    const char *port = NULL;
    char *sockpath = NULL;
    char *device = NULL;
    off_t fd_size;
    QemuOpts *sn_opts = NULL;
    const char *sn_id_or_name = NULL;
    const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:";
    struct option lopt[] = {
        { "help", 0, NULL, 'h' },
        { "version", 0, NULL, 'V' },
        { "bind", 1, NULL, 'b' },
        { "port", 1, NULL, 'p' },
        { "socket", 1, NULL, 'k' },
        { "offset", 1, NULL, 'o' },
        { "read-only", 0, NULL, 'r' },
        { "partition", 1, NULL, 'P' },
        { "connect", 1, NULL, 'c' },
        { "disconnect", 0, NULL, 'd' },
        { "snapshot", 0, NULL, 's' },
        { "load-snapshot", 1, NULL, 'l' },
        { "nocache", 0, NULL, 'n' },
        { "cache", 1, NULL, QEMU_NBD_OPT_CACHE },
        { "aio", 1, NULL, QEMU_NBD_OPT_AIO },
        { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD },
        { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES },
        { "shared", 1, NULL, 'e' },
        { "format", 1, NULL, 'f' },
        { "persistent", 0, NULL, 't' },
        { "verbose", 0, NULL, 'v' },
        { NULL, 0, NULL, 0 }
    };
    int ch;
    int opt_ind = 0;
    char *end;
    int flags = BDRV_O_RDWR;
    int partition = -1;
    int ret = 0;
    int fd;
    bool seen_cache = false;
    bool seen_discard = false;
    bool seen_aio = false;
    pthread_t client_thread;
    const char *fmt = NULL;
    Error *local_err = NULL;
    BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
    QDict *options = NULL;

    /* The client thread uses SIGTERM to interrupt the server.  A signal
     * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
     */
    struct sigaction sa_sigterm;
    memset(&sa_sigterm, 0, sizeof(sa_sigterm));
    sa_sigterm.sa_handler = termsig_handler;
    sigaction(SIGTERM, &sa_sigterm, NULL);
    qemu_init_exec_dir(argv[0]);

    while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
        switch (ch) {
        case 's':
            flags |= BDRV_O_SNAPSHOT;
            break;
        case 'n':
            optarg = (char *) "none";
            /* fallthrough */
        case QEMU_NBD_OPT_CACHE:
            if (seen_cache) {
                errx(EXIT_FAILURE, "-n and --cache can only be specified once");
            }
            seen_cache = true;
            if (bdrv_parse_cache_flags(optarg, &flags) == -1) {
                errx(EXIT_FAILURE, "Invalid cache mode `%s'", optarg);
            }
            break;
        case QEMU_NBD_OPT_AIO:
            if (seen_aio) {
                errx(EXIT_FAILURE, "--aio can only be specified once");
            }
            seen_aio = true;
            if (!strcmp(optarg, "native")) {
                flags |= BDRV_O_NATIVE_AIO;
            } else if (!strcmp(optarg, "threads")) {
                /* this is the default */
            } else {
               errx(EXIT_FAILURE, "invalid aio mode `%s'", optarg);
            }
            break;
        case QEMU_NBD_OPT_DISCARD:
            if (seen_discard) {
                errx(EXIT_FAILURE, "--discard can only be specified once");
            }
            seen_discard = true;
            if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
                errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg);
            }
            break;
        case QEMU_NBD_OPT_DETECT_ZEROES:
            detect_zeroes =
                qapi_enum_parse(BlockdevDetectZeroesOptions_lookup,
                                optarg,
                                BLOCKDEV_DETECT_ZEROES_OPTIONS_MAX,
                                BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
                                &local_err);
            if (local_err) {
                errx(EXIT_FAILURE, "Failed to parse detect_zeroes mode: %s", 
                     error_get_pretty(local_err));
            }
            if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
                !(flags & BDRV_O_UNMAP)) {
                errx(EXIT_FAILURE, "setting detect-zeroes to unmap is not allowed "
                                   "without setting discard operation to unmap"); 
            }
            break;
        case 'b':
            bindto = optarg;
            break;
        case 'p':
            port = optarg;
            break;
        case 'o':
                dev_offset = strtoll (optarg, &end, 0);
            if (*end) {
                errx(EXIT_FAILURE, "Invalid offset `%s'", optarg);
            }
            if (dev_offset < 0) {
                errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg);
            }
            break;
        case 'l':
            if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
                sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
                                                  optarg, false);
                if (!sn_opts) {
                    errx(EXIT_FAILURE, "Failed in parsing snapshot param `%s'",
                         optarg);
                }
            } else {
                sn_id_or_name = optarg;
            }
            /* fall through */
        case 'r':
            nbdflags |= NBD_FLAG_READ_ONLY;
            flags &= ~BDRV_O_RDWR;
            break;
        case 'P':
            partition = strtol(optarg, &end, 0);
            if (*end) {
                errx(EXIT_FAILURE, "Invalid partition `%s'", optarg);
            }
            if (partition < 1 || partition > 8) {
                errx(EXIT_FAILURE, "Invalid partition %d", partition);
            }
            break;
        case 'k':
            sockpath = optarg;
            if (sockpath[0] != '/') {
                errx(EXIT_FAILURE, "socket path must be absolute\n");
            }
            break;
        case 'd':
            disconnect = true;
            break;
        case 'c':
            device = optarg;
            break;
        case 'e':
            shared = strtol(optarg, &end, 0);
            if (*end) {
                errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg);
            }
            if (shared < 1) {
                errx(EXIT_FAILURE, "Shared device number must be greater than 0\n");
            }
            break;
        case 'f':
            fmt = optarg;
            break;
        case 't':
            persistent = 1;
            break;
        case 'v':
            verbose = 1;
            break;
        case 'V':
            version(argv[0]);
            exit(0);
            break;
        case 'h':
            usage(argv[0]);
            exit(0);
            break;
        case '?':
            errx(EXIT_FAILURE, "Try `%s --help' for more information.",
                 argv[0]);
        }
    }

    if ((argc - optind) != 1) {
        errx(EXIT_FAILURE, "Invalid number of argument.\n"
             "Try `%s --help' for more information.",
             argv[0]);
    }

    if (disconnect) {
        fd = open(argv[optind], O_RDWR);
        if (fd < 0) {
            err(EXIT_FAILURE, "Cannot open %s", argv[optind]);
        }
        nbd_disconnect(fd);

        close(fd);

        printf("%s disconnected\n", argv[optind]);

        return 0;
    }

    if (device && !verbose) {
        int stderr_fd[2];
        pid_t pid;
        int ret;

        if (qemu_pipe(stderr_fd) < 0) {
            err(EXIT_FAILURE, "Error setting up communication pipe");
        }

        /* Now daemonize, but keep a communication channel open to
         * print errors and exit with the proper status code.
         */
        pid = fork();
        if (pid < 0) {
            err(EXIT_FAILURE, "Failed to fork");
        } else if (pid == 0) {
            close(stderr_fd[0]);
            ret = qemu_daemon(1, 0);

            /* Temporarily redirect stderr to the parent's pipe...  */
            dup2(stderr_fd[1], STDERR_FILENO);
            if (ret < 0) {
                err(EXIT_FAILURE, "Failed to daemonize");
            }

            /* ... close the descriptor we inherited and go on.  */
            close(stderr_fd[1]);
        } else {
            bool errors = false;
            char *buf;

            /* In the parent.  Print error messages from the child until
             * it closes the pipe.
             */
            close(stderr_fd[1]);
            buf = g_malloc(1024);
            while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
                errors = true;
                ret = qemu_write_full(STDERR_FILENO, buf, ret);
                if (ret < 0) {
                    exit(EXIT_FAILURE);
                }
            }
            if (ret < 0) {
                err(EXIT_FAILURE, "Cannot read from daemon");
            }

            /* Usually the daemon should not print any message.
             * Exit with zero status in that case.
             */
            exit(errors);
        }
    }

    if (device != NULL && sockpath == NULL) {
        sockpath = g_malloc(128);
        snprintf(sockpath, 128, SOCKET_PATH, basename(device));
    }

    saddr = nbd_build_socket_address(sockpath, bindto, port);

    if (qemu_init_main_loop(&local_err)) {
        error_report_err(local_err);
        exit(EXIT_FAILURE);
    }
    bdrv_init();
    atexit(bdrv_close_all);

    if (fmt) {
        options = qdict_new();
        qdict_put(options, "driver", qstring_from_str(fmt));
    }

    srcpath = argv[optind];
    blk = blk_new_open("hda", srcpath, NULL, options, flags, &local_err);
    if (!blk) {
        errx(EXIT_FAILURE, "Failed to blk_new_open '%s': %s", argv[optind],
             error_get_pretty(local_err));
    }
    bs = blk_bs(blk);

    if (sn_opts) {
        ret = bdrv_snapshot_load_tmp(bs,
                                     qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
                                     qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
                                     &local_err);
    } else if (sn_id_or_name) {
        ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
                                                   &local_err);
    }
    if (ret < 0) {
        errno = -ret;
        err(EXIT_FAILURE,
            "Failed to load snapshot: %s",
            error_get_pretty(local_err));
    }

    bs->detect_zeroes = detect_zeroes;
    fd_size = blk_getlength(blk);
    if (fd_size < 0) {
        errx(EXIT_FAILURE, "Failed to determine the image length: %s",
             strerror(-fd_size));
    }

    if (partition != -1) {
        ret = find_partition(blk, partition, &dev_offset, &fd_size);
        if (ret < 0) {
            errno = -ret;
            err(EXIT_FAILURE, "Could not find partition %d", partition);
        }
    }

    exp = nbd_export_new(blk, dev_offset, fd_size, nbdflags, nbd_export_closed,
                         &local_err);
    if (!exp) {
        errx(EXIT_FAILURE, "%s", error_get_pretty(local_err));
    }

    fd = socket_listen(saddr, &local_err);
    if (fd < 0) {
        error_report_err(local_err);
        return 1;
    }

    if (device) {
        int ret;

        ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
        if (ret != 0) {
            errx(EXIT_FAILURE, "Failed to create client thread: %s",
                 strerror(ret));
        }
    } else {
        /* Shut up GCC warnings.  */
        memset(&client_thread, 0, sizeof(client_thread));
    }

    server_fd = fd;
    nbd_update_server_fd_handler(fd);

    /* now when the initialization is (almost) complete, chdir("/")
     * to free any busy filesystems */
    if (chdir("/") < 0) {
        err(EXIT_FAILURE, "Could not chdir to root directory");
    }

    state = RUNNING;
    do {
        main_loop_wait(false);
        if (state == TERMINATE) {
            state = TERMINATING;
            nbd_export_close(exp);
            nbd_export_put(exp);
            exp = NULL;
        }
    } while (state != TERMINATED);

    blk_unref(blk);
    if (sockpath) {
        unlink(sockpath);
    }

    qemu_opts_del(sn_opts);

    if (device) {
        void *ret;
        pthread_join(client_thread, &ret);
        exit(ret != NULL);
    } else {
        exit(EXIT_SUCCESS);
    }
}
Beispiel #2
0
int main(int argc, char **argv)
{
    BlockBackend *blk;
    BlockDriverState *bs;
    off_t dev_offset = 0;
    uint16_t nbdflags = 0;
    bool disconnect = false;
    const char *bindto = NULL;
    const char *port = NULL;
    char *sockpath = NULL;
    char *device = NULL;
    off_t fd_size;
    QemuOpts *sn_opts = NULL;
    const char *sn_id_or_name = NULL;
    const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:";
    struct option lopt[] = {
        { "help", no_argument, NULL, 'h' },
        { "version", no_argument, NULL, 'V' },
        { "bind", required_argument, NULL, 'b' },
        { "port", required_argument, NULL, 'p' },
        { "socket", required_argument, NULL, 'k' },
        { "offset", required_argument, NULL, 'o' },
        { "read-only", no_argument, NULL, 'r' },
        { "partition", required_argument, NULL, 'P' },
        { "connect", required_argument, NULL, 'c' },
        { "disconnect", no_argument, NULL, 'd' },
        { "snapshot", no_argument, NULL, 's' },
        { "load-snapshot", required_argument, NULL, 'l' },
        { "nocache", no_argument, NULL, 'n' },
        { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE },
        { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO },
        { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD },
        { "detect-zeroes", required_argument, NULL,
          QEMU_NBD_OPT_DETECT_ZEROES },
        { "shared", required_argument, NULL, 'e' },
        { "format", required_argument, NULL, 'f' },
        { "persistent", no_argument, NULL, 't' },
        { "verbose", no_argument, NULL, 'v' },
        { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT },
        { "export-name", required_argument, NULL, 'x' },
        { "description", required_argument, NULL, 'D' },
        { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
        { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
        { "trace", required_argument, NULL, 'T' },
        { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK },
        { NULL, 0, NULL, 0 }
    };
    int ch;
    int opt_ind = 0;
    char *end;
    int flags = BDRV_O_RDWR;
    int partition = -1;
    int ret = 0;
    bool seen_cache = false;
    bool seen_discard = false;
    bool seen_aio = false;
    pthread_t client_thread;
    const char *fmt = NULL;
    Error *local_err = NULL;
    BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
    QDict *options = NULL;
    const char *export_name = NULL;
    const char *export_description = NULL;
    const char *tlscredsid = NULL;
    bool imageOpts = false;
    bool writethrough = true;
    char *trace_file = NULL;
    bool fork_process = false;
    int old_stderr = -1;
    unsigned socket_activation;

    /* The client thread uses SIGTERM to interrupt the server.  A signal
     * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
     */
    struct sigaction sa_sigterm;
    memset(&sa_sigterm, 0, sizeof(sa_sigterm));
    sa_sigterm.sa_handler = termsig_handler;
    sigaction(SIGTERM, &sa_sigterm, NULL);

#ifdef CONFIG_POSIX
    signal(SIGPIPE, SIG_IGN);
#endif

    module_call_init(MODULE_INIT_TRACE);
    qcrypto_init(&error_fatal);

    module_call_init(MODULE_INIT_QOM);
    qemu_add_opts(&qemu_object_opts);
    qemu_add_opts(&qemu_trace_opts);
    qemu_init_exec_dir(argv[0]);

    while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
        switch (ch) {
        case 's':
            flags |= BDRV_O_SNAPSHOT;
            break;
        case 'n':
            optarg = (char *) "none";
            /* fallthrough */
        case QEMU_NBD_OPT_CACHE:
            if (seen_cache) {
                error_report("-n and --cache can only be specified once");
                exit(EXIT_FAILURE);
            }
            seen_cache = true;
            if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) {
                error_report("Invalid cache mode `%s'", optarg);
                exit(EXIT_FAILURE);
            }
            break;
        case QEMU_NBD_OPT_AIO:
            if (seen_aio) {
                error_report("--aio can only be specified once");
                exit(EXIT_FAILURE);
            }
            seen_aio = true;
            if (!strcmp(optarg, "native")) {
                flags |= BDRV_O_NATIVE_AIO;
            } else if (!strcmp(optarg, "threads")) {
                /* this is the default */
            } else {
               error_report("invalid aio mode `%s'", optarg);
               exit(EXIT_FAILURE);
            }
            break;
        case QEMU_NBD_OPT_DISCARD:
            if (seen_discard) {
                error_report("--discard can only be specified once");
                exit(EXIT_FAILURE);
            }
            seen_discard = true;
            if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
                error_report("Invalid discard mode `%s'", optarg);
                exit(EXIT_FAILURE);
            }
            break;
        case QEMU_NBD_OPT_DETECT_ZEROES:
            detect_zeroes =
                qapi_enum_parse(BlockdevDetectZeroesOptions_lookup,
                                optarg,
                                BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX,
                                BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
                                &local_err);
            if (local_err) {
                error_reportf_err(local_err,
                                  "Failed to parse detect_zeroes mode: ");
                exit(EXIT_FAILURE);
            }
            if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
                !(flags & BDRV_O_UNMAP)) {
                error_report("setting detect-zeroes to unmap is not allowed "
                             "without setting discard operation to unmap");
                exit(EXIT_FAILURE);
            }
            break;
        case 'b':
            bindto = optarg;
            break;
        case 'p':
            port = optarg;
            break;
        case 'o':
                dev_offset = strtoll (optarg, &end, 0);
            if (*end) {
                error_report("Invalid offset `%s'", optarg);
                exit(EXIT_FAILURE);
            }
            if (dev_offset < 0) {
                error_report("Offset must be positive `%s'", optarg);
                exit(EXIT_FAILURE);
            }
            break;
        case 'l':
            if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
                sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
                                                  optarg, false);
                if (!sn_opts) {
                    error_report("Failed in parsing snapshot param `%s'",
                                 optarg);
                    exit(EXIT_FAILURE);
                }
            } else {
                sn_id_or_name = optarg;
            }
            /* fall through */
        case 'r':
            nbdflags |= NBD_FLAG_READ_ONLY;
            flags &= ~BDRV_O_RDWR;
            break;
        case 'P':
            partition = strtol(optarg, &end, 0);
            if (*end) {
                error_report("Invalid partition `%s'", optarg);
                exit(EXIT_FAILURE);
            }
            if (partition < 1 || partition > 8) {
                error_report("Invalid partition %d", partition);
                exit(EXIT_FAILURE);
            }
            break;
        case 'k':
            sockpath = optarg;
            if (sockpath[0] != '/') {
                error_report("socket path must be absolute");
                exit(EXIT_FAILURE);
            }
            break;
        case 'd':
            disconnect = true;
            break;
        case 'c':
            device = optarg;
            break;
        case 'e':
            shared = strtol(optarg, &end, 0);
            if (*end) {
                error_report("Invalid shared device number '%s'", optarg);
                exit(EXIT_FAILURE);
            }
            if (shared < 1) {
                error_report("Shared device number must be greater than 0");
                exit(EXIT_FAILURE);
            }
            break;
        case 'f':
            fmt = optarg;
            break;
        case 't':
            persistent = 1;
            break;
        case 'x':
            export_name = optarg;
            break;
        case 'D':
            export_description = optarg;
            break;
        case 'v':
            verbose = 1;
            break;
        case 'V':
            version(argv[0]);
            exit(0);
            break;
        case 'h':
            usage(argv[0]);
            exit(0);
            break;
        case '?':
            error_report("Try `%s --help' for more information.", argv[0]);
            exit(EXIT_FAILURE);
        case QEMU_NBD_OPT_OBJECT: {
            QemuOpts *opts;
            opts = qemu_opts_parse_noisily(&qemu_object_opts,
                                           optarg, true);
            if (!opts) {
                exit(EXIT_FAILURE);
            }
        }   break;
        case QEMU_NBD_OPT_TLSCREDS:
            tlscredsid = optarg;
            break;
        case QEMU_NBD_OPT_IMAGE_OPTS:
            imageOpts = true;
            break;
        case 'T':
            g_free(trace_file);
            trace_file = trace_opt_parse(optarg);
            break;
        case QEMU_NBD_OPT_FORK:
            fork_process = true;
            break;
        }
    }

    if ((argc - optind) != 1) {
        error_report("Invalid number of arguments");
        error_printf("Try `%s --help' for more information.\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    if (qemu_opts_foreach(&qemu_object_opts,
                          user_creatable_add_opts_foreach,
                          NULL, NULL)) {
        exit(EXIT_FAILURE);
    }

    if (!trace_init_backends()) {
        exit(1);
    }
    trace_init_file(trace_file);
    qemu_set_log(LOG_TRACE);

    socket_activation = check_socket_activation();
    if (socket_activation == 0) {
        setup_address_and_port(&bindto, &port);
    } else {
        /* Using socket activation - check user didn't use -p etc. */
        const char *err_msg = socket_activation_validate_opts(device, sockpath,
                                                              bindto, port);
        if (err_msg != NULL) {
            error_report("%s", err_msg);
            exit(EXIT_FAILURE);
        }

        /* qemu-nbd can only listen on a single socket.  */
        if (socket_activation > 1) {
            error_report("qemu-nbd does not support socket activation with %s > 1",
                         "LISTEN_FDS");
            exit(EXIT_FAILURE);
        }
    }

    if (tlscredsid) {
        if (sockpath) {
            error_report("TLS is only supported with IPv4/IPv6");
            exit(EXIT_FAILURE);
        }
        if (device) {
            error_report("TLS is not supported with a host device");
            exit(EXIT_FAILURE);
        }
        if (!export_name) {
            /* Set the default NBD protocol export name, since
             * we *must* use new style protocol for TLS */
            export_name = "";
        }
        tlscreds = nbd_get_tls_creds(tlscredsid, &local_err);
        if (local_err) {
            error_report("Failed to get TLS creds %s",
                         error_get_pretty(local_err));
            exit(EXIT_FAILURE);
        }
    }

    if (disconnect) {
        int nbdfd = open(argv[optind], O_RDWR);
        if (nbdfd < 0) {
            error_report("Cannot open %s: %s", argv[optind],
                         strerror(errno));
            exit(EXIT_FAILURE);
        }
        nbd_disconnect(nbdfd);

        close(nbdfd);

        printf("%s disconnected\n", argv[optind]);

        return 0;
    }

    if ((device && !verbose) || fork_process) {
        int stderr_fd[2];
        pid_t pid;
        int ret;

        if (qemu_pipe(stderr_fd) < 0) {
            error_report("Error setting up communication pipe: %s",
                         strerror(errno));
            exit(EXIT_FAILURE);
        }

        /* Now daemonize, but keep a communication channel open to
         * print errors and exit with the proper status code.
         */
        pid = fork();
        if (pid < 0) {
            error_report("Failed to fork: %s", strerror(errno));
            exit(EXIT_FAILURE);
        } else if (pid == 0) {
            close(stderr_fd[0]);
            ret = qemu_daemon(1, 0);

            /* Temporarily redirect stderr to the parent's pipe...  */
            old_stderr = dup(STDERR_FILENO);
            dup2(stderr_fd[1], STDERR_FILENO);
            if (ret < 0) {
                error_report("Failed to daemonize: %s", strerror(errno));
                exit(EXIT_FAILURE);
            }

            /* ... close the descriptor we inherited and go on.  */
            close(stderr_fd[1]);
        } else {
            bool errors = false;
            char *buf;

            /* In the parent.  Print error messages from the child until
             * it closes the pipe.
             */
            close(stderr_fd[1]);
            buf = g_malloc(1024);
            while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
                errors = true;
                ret = qemu_write_full(STDERR_FILENO, buf, ret);
                if (ret < 0) {
                    exit(EXIT_FAILURE);
                }
            }
            if (ret < 0) {
                error_report("Cannot read from daemon: %s",
                             strerror(errno));
                exit(EXIT_FAILURE);
            }

            /* Usually the daemon should not print any message.
             * Exit with zero status in that case.
             */
            exit(errors);
        }
    }

    if (device != NULL && sockpath == NULL) {
        sockpath = g_malloc(128);
        snprintf(sockpath, 128, SOCKET_PATH, basename(device));
    }

    if (socket_activation == 0) {
        server_ioc = qio_channel_socket_new();
        saddr = nbd_build_socket_address(sockpath, bindto, port);
        if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) {
            object_unref(OBJECT(server_ioc));
            error_report_err(local_err);
            return 1;
        }
    } else {
        /* See comment in check_socket_activation above. */
        assert(socket_activation == 1);
        server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD,
                                               &local_err);
        if (server_ioc == NULL) {
            error_report("Failed to use socket activation: %s",
                         error_get_pretty(local_err));
            exit(EXIT_FAILURE);
        }
    }

    if (qemu_init_main_loop(&local_err)) {
        error_report_err(local_err);
        exit(EXIT_FAILURE);
    }
    bdrv_init();
    atexit(bdrv_close_all);

    srcpath = argv[optind];
    if (imageOpts) {
        QemuOpts *opts;
        if (fmt) {
            error_report("--image-opts and -f are mutually exclusive");
            exit(EXIT_FAILURE);
        }
        opts = qemu_opts_parse_noisily(&file_opts, srcpath, true);
        if (!opts) {
            qemu_opts_reset(&file_opts);
            exit(EXIT_FAILURE);
        }
        options = qemu_opts_to_qdict(opts, NULL);
        qemu_opts_reset(&file_opts);
        blk = blk_new_open(NULL, NULL, options, flags, &local_err);
    } else {
        if (fmt) {
            options = qdict_new();
            qdict_put_str(options, "driver", fmt);
        }
        blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
    }

    if (!blk) {
        error_reportf_err(local_err, "Failed to blk_new_open '%s': ",
                          argv[optind]);
        exit(EXIT_FAILURE);
    }
    bs = blk_bs(blk);

    blk_set_enable_write_cache(blk, !writethrough);

    if (sn_opts) {
        ret = bdrv_snapshot_load_tmp(bs,
                                     qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
                                     qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
                                     &local_err);
    } else if (sn_id_or_name) {
        ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name,
                                                   &local_err);
    }
    if (ret < 0) {
        error_reportf_err(local_err, "Failed to load snapshot: ");
        exit(EXIT_FAILURE);
    }

    bs->detect_zeroes = detect_zeroes;
    fd_size = blk_getlength(blk);
    if (fd_size < 0) {
        error_report("Failed to determine the image length: %s",
                     strerror(-fd_size));
        exit(EXIT_FAILURE);
    }

    if (dev_offset >= fd_size) {
        error_report("Offset (%lld) has to be smaller than the image size "
                     "(%lld)",
                     (long long int)dev_offset, (long long int)fd_size);
        exit(EXIT_FAILURE);
    }
    fd_size -= dev_offset;

    if (partition != -1) {
        ret = find_partition(blk, partition, &dev_offset, &fd_size);
        if (ret < 0) {
            error_report("Could not find partition %d: %s", partition,
                         strerror(-ret));
            exit(EXIT_FAILURE);
        }
    }

    exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed,
                         writethrough, NULL, &local_err);
    if (!exp) {
        error_report_err(local_err);
        exit(EXIT_FAILURE);
    }
    if (export_name) {
        nbd_export_set_name(exp, export_name);
        nbd_export_set_description(exp, export_description);
        newproto = true;
    } else if (export_description) {
        error_report("Export description requires an export name");
        exit(EXIT_FAILURE);
    }

    if (device) {
        int ret;

        ret = pthread_create(&client_thread, NULL, nbd_client_thread, device);
        if (ret != 0) {
            error_report("Failed to create client thread: %s", strerror(ret));
            exit(EXIT_FAILURE);
        }
    } else {
        /* Shut up GCC warnings.  */
        memset(&client_thread, 0, sizeof(client_thread));
    }

    nbd_update_server_watch();

    /* now when the initialization is (almost) complete, chdir("/")
     * to free any busy filesystems */
    if (chdir("/") < 0) {
        error_report("Could not chdir to root directory: %s",
                     strerror(errno));
        exit(EXIT_FAILURE);
    }

    if (fork_process) {
        dup2(old_stderr, STDERR_FILENO);
        close(old_stderr);
    }

    state = RUNNING;
    do {
        main_loop_wait(false);
        if (state == TERMINATE) {
            state = TERMINATING;
            nbd_export_close(exp);
            nbd_export_put(exp);
            exp = NULL;
        }
    } while (state != TERMINATED);

    blk_unref(blk);
    if (sockpath) {
        unlink(sockpath);
    }

    qemu_opts_del(sn_opts);

    if (device) {
        void *ret;
        pthread_join(client_thread, &ret);
        exit(ret != NULL);
    } else {
        exit(EXIT_SUCCESS);
    }
}
Beispiel #3
0
int main(int argc, char **argv)
{
    int readonly = 0;
    int growable = 0;
    const char *sopt = "hVc:d:rsnmgkt:T:";
    const struct option lopt[] = {
        { "help", 0, NULL, 'h' },
        { "version", 0, NULL, 'V' },
        { "offset", 1, NULL, 'o' },
        { "cmd", 1, NULL, 'c' },
        { "read-only", 0, NULL, 'r' },
        { "snapshot", 0, NULL, 's' },
        { "nocache", 0, NULL, 'n' },
        { "misalign", 0, NULL, 'm' },
        { "growable", 0, NULL, 'g' },
        { "native-aio", 0, NULL, 'k' },
        { "discard", 1, NULL, 'd' },
        { "cache", 1, NULL, 't' },
        { "trace", 1, NULL, 'T' },
        { NULL, 0, NULL, 0 }
    };
    int c;
    int opt_index = 0;
    int flags = BDRV_O_UNMAP;

#ifdef CONFIG_POSIX
    signal(SIGPIPE, SIG_IGN);
#endif

    progname = basename(argv[0]);
    qemu_init_exec_dir(argv[0]);

    while ((c = getopt_long(argc, argv, sopt, lopt, &opt_index)) != -1) {
        switch (c) {
        case 's':
            flags |= BDRV_O_SNAPSHOT;
            break;
        case 'n':
            flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
            break;
        case 'd':
            if (bdrv_parse_discard_flags(optarg, &flags) < 0) {
                error_report("Invalid discard option: %s", optarg);
                exit(1);
            }
            break;
        case 'c':
            add_user_command(optarg);
            break;
        case 'r':
            readonly = 1;
            break;
        case 'm':
            qemuio_misalign = true;
            break;
        case 'g':
            growable = 1;
            break;
        case 'k':
            flags |= BDRV_O_NATIVE_AIO;
            break;
        case 't':
            if (bdrv_parse_cache_flags(optarg, &flags) < 0) {
                error_report("Invalid cache option: %s", optarg);
                exit(1);
            }
            break;
        case 'T':
            if (!trace_backend_init(optarg, NULL)) {
                exit(1); /* error message will have been printed */
            }
            break;
        case 'V':
            printf("%s version %s\n", progname, QEMU_VERSION);
            exit(0);
        case 'h':
            usage(progname);
            exit(0);
        default:
            usage(progname);
            exit(1);
        }
    }

    if ((argc - optind) > 1) {
        usage(progname);
        exit(1);
    }

    qemu_init_main_loop();
    bdrv_init();

    /* initialize commands */
    qemuio_add_command(&quit_cmd);
    qemuio_add_command(&open_cmd);
    qemuio_add_command(&close_cmd);

    if (isatty(STDIN_FILENO)) {
        readline_state = readline_init(readline_printf_func,
                                       readline_flush_func,
                                       NULL,
                                       readline_completion_func);
        qemu_set_tty_echo(STDIN_FILENO, false);
        atexit(reenable_tty_echo);
    }

    /* open the device */
    if (!readonly) {
        flags |= BDRV_O_RDWR;
    }

    if ((argc - optind) == 1) {
        openfile(argv[optind], flags, growable, NULL);
    }
    command_loop();

    /*
     * Make sure all outstanding requests complete before the program exits.
     */
    bdrv_drain_all();

    if (qemuio_bs) {
        bdrv_unref(qemuio_bs);
    }
    g_free(readline_state);
    return 0;
}