1 /* 2 * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws> 3 * 4 * Network Block Device 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; under version 2 of the License. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include "qemu/osdep.h" 20 #include <getopt.h> 21 #include <libgen.h> 22 #include <pthread.h> 23 24 #include "qemu-common.h" 25 #include "qapi/error.h" 26 #include "qemu/cutils.h" 27 #include "sysemu/block-backend.h" 28 #include "block/block_int.h" 29 #include "block/nbd.h" 30 #include "qemu/main-loop.h" 31 #include "qemu/module.h" 32 #include "qemu/option.h" 33 #include "qemu/error-report.h" 34 #include "qemu/config-file.h" 35 #include "qemu/bswap.h" 36 #include "qemu/log.h" 37 #include "qemu/systemd.h" 38 #include "block/snapshot.h" 39 #include "qapi/qmp/qdict.h" 40 #include "qapi/qmp/qstring.h" 41 #include "qom/object_interfaces.h" 42 #include "io/channel-socket.h" 43 #include "io/net-listener.h" 44 #include "crypto/init.h" 45 #include "trace/control.h" 46 #include "qemu-version.h" 47 48 #ifdef __linux__ 49 #define HAVE_NBD_DEVICE 1 50 #else 51 #define HAVE_NBD_DEVICE 0 52 #endif 53 54 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 55 #define QEMU_NBD_OPT_CACHE 256 56 #define QEMU_NBD_OPT_AIO 257 57 #define QEMU_NBD_OPT_DISCARD 258 58 #define QEMU_NBD_OPT_DETECT_ZEROES 259 59 #define QEMU_NBD_OPT_OBJECT 260 60 #define QEMU_NBD_OPT_TLSCREDS 261 61 #define QEMU_NBD_OPT_IMAGE_OPTS 262 62 #define QEMU_NBD_OPT_FORK 263 63 #define QEMU_NBD_OPT_TLSAUTHZ 264 64 #define QEMU_NBD_OPT_PID_FILE 265 65 66 #define MBR_SIZE 512 67 68 static NBDExport *export; 69 static int verbose; 70 static char *srcpath; 71 static SocketAddress *saddr; 72 static int persistent = 0; 73 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 74 static int shared = 1; 75 static int nb_fds; 76 static QIONetListener *server; 77 static QCryptoTLSCreds *tlscreds; 78 static const char *tlsauthz; 79 80 static void usage(const char *name) 81 { 82 (printf) ( 83 "Usage: %s [OPTIONS] FILE\n" 84 " or: %s -L [OPTIONS]\n" 85 "QEMU Disk Network Block Device Utility\n" 86 "\n" 87 " -h, --help display this help and exit\n" 88 " -V, --version output version information and exit\n" 89 "\n" 90 "Connection properties:\n" 91 " -p, --port=PORT port to listen on (default `%d')\n" 92 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 93 " -k, --socket=PATH path to the unix socket\n" 94 " (default '"SOCKET_PATH"')\n" 95 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 96 " -t, --persistent don't exit on the last connection\n" 97 " -v, --verbose display extra debugging information\n" 98 " -x, --export-name=NAME expose export by name (default is empty string)\n" 99 " -D, --description=TEXT export a human-readable description\n" 100 "\n" 101 "Exposing part of the image:\n" 102 " -o, --offset=OFFSET offset into the image\n" 103 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 104 "\n" 105 "General purpose options:\n" 106 " -L, --list list exports available from another NBD server\n" 107 " --object type,id=ID,... define an object such as 'secret' for providing\n" 108 " passwords and/or encryption keys\n" 109 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 110 " --tls-authz=ID use id of an earlier --object to provide\n" 111 " authorization\n" 112 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 113 " specify tracing options\n" 114 " --fork fork off the server process and exit the parent\n" 115 " once the server is running\n" 116 " --pid-file=PATH store the server's process ID in the given file\n" 117 #if HAVE_NBD_DEVICE 118 "\n" 119 "Kernel NBD client support:\n" 120 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 121 " -d, --disconnect disconnect the specified device\n" 122 #endif 123 "\n" 124 "Block device options:\n" 125 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 126 " -r, --read-only export read-only\n" 127 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 128 " file with backing_file=FILE, redirect the write to\n" 129 " the temporary one\n" 130 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 131 " load an internal snapshot inside FILE and export it\n" 132 " as an read-only device, SNAPSHOT_PARAM format is\n" 133 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 134 " '[ID_OR_NAME]'\n" 135 " -n, --nocache disable host cache\n" 136 " --cache=MODE set cache mode (none, writeback, ...)\n" 137 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 138 " --discard=MODE set discard mode (ignore, unmap)\n" 139 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 140 " --image-opts treat FILE as a full set of image options\n" 141 "\n" 142 QEMU_HELP_BOTTOM "\n" 143 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 144 } 145 146 static void version(const char *name) 147 { 148 printf( 149 "%s " QEMU_FULL_VERSION "\n" 150 "Written by Anthony Liguori.\n" 151 "\n" 152 QEMU_COPYRIGHT "\n" 153 "This is free software; see the source for copying conditions. There is NO\n" 154 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 155 , name); 156 } 157 158 static void termsig_handler(int signum) 159 { 160 atomic_cmpxchg(&state, RUNNING, TERMINATE); 161 qemu_notify_event(); 162 } 163 164 165 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 166 const char *hostname) 167 { 168 int ret = EXIT_FAILURE; 169 int rc; 170 Error *err = NULL; 171 QIOChannelSocket *sioc; 172 NBDExportInfo *list; 173 int i, j; 174 175 sioc = qio_channel_socket_new(); 176 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 177 error_report_err(err); 178 return EXIT_FAILURE; 179 } 180 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 181 &err); 182 if (rc < 0) { 183 if (err) { 184 error_report_err(err); 185 } 186 goto out; 187 } 188 printf("exports available: %d\n", rc); 189 for (i = 0; i < rc; i++) { 190 printf(" export: '%s'\n", list[i].name); 191 if (list[i].description && *list[i].description) { 192 printf(" description: %s\n", list[i].description); 193 } 194 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 195 static const char *const flag_names[] = { 196 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 197 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 198 [NBD_FLAG_SEND_FUA_BIT] = "fua", 199 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 200 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 201 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 202 [NBD_FLAG_SEND_DF_BIT] = "df", 203 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 204 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 205 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 206 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 207 }; 208 209 printf(" size: %" PRIu64 "\n", list[i].size); 210 printf(" flags: 0x%x (", list[i].flags); 211 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 212 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 213 printf(" %s", flag_names[bit]); 214 } 215 } 216 printf(" )\n"); 217 } 218 if (list[i].min_block) { 219 printf(" min block: %u\n", list[i].min_block); 220 printf(" opt block: %u\n", list[i].opt_block); 221 printf(" max block: %u\n", list[i].max_block); 222 } 223 if (list[i].n_contexts) { 224 printf(" available meta contexts: %d\n", list[i].n_contexts); 225 for (j = 0; j < list[i].n_contexts; j++) { 226 printf(" %s\n", list[i].contexts[j]); 227 } 228 } 229 } 230 nbd_free_export_list(list, rc); 231 232 ret = EXIT_SUCCESS; 233 out: 234 object_unref(OBJECT(sioc)); 235 return ret; 236 } 237 238 239 #if HAVE_NBD_DEVICE 240 static void *show_parts(void *arg) 241 { 242 char *device = arg; 243 int nbd; 244 245 /* linux just needs an open() to trigger 246 * the partition table update 247 * but remember to load the module with max_part != 0 : 248 * modprobe nbd max_part=63 249 */ 250 nbd = open(device, O_RDWR); 251 if (nbd >= 0) { 252 close(nbd); 253 } 254 return NULL; 255 } 256 257 static void *nbd_client_thread(void *arg) 258 { 259 char *device = arg; 260 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 261 QIOChannelSocket *sioc; 262 int fd; 263 int ret; 264 pthread_t show_parts_thread; 265 Error *local_error = NULL; 266 267 sioc = qio_channel_socket_new(); 268 if (qio_channel_socket_connect_sync(sioc, 269 saddr, 270 &local_error) < 0) { 271 error_report_err(local_error); 272 goto out; 273 } 274 275 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 276 NULL, NULL, NULL, &info, &local_error); 277 if (ret < 0) { 278 if (local_error) { 279 error_report_err(local_error); 280 } 281 goto out_socket; 282 } 283 284 fd = open(device, O_RDWR); 285 if (fd < 0) { 286 /* Linux-only, we can use %m in printf. */ 287 error_report("Failed to open %s: %m", device); 288 goto out_socket; 289 } 290 291 ret = nbd_init(fd, sioc, &info, &local_error); 292 if (ret < 0) { 293 error_report_err(local_error); 294 goto out_fd; 295 } 296 297 /* update partition table */ 298 pthread_create(&show_parts_thread, NULL, show_parts, device); 299 300 if (verbose) { 301 fprintf(stderr, "NBD device %s is now connected to %s\n", 302 device, srcpath); 303 } else { 304 /* Close stderr so that the qemu-nbd process exits. */ 305 dup2(STDOUT_FILENO, STDERR_FILENO); 306 } 307 308 ret = nbd_client(fd); 309 if (ret) { 310 goto out_fd; 311 } 312 close(fd); 313 object_unref(OBJECT(sioc)); 314 g_free(info.name); 315 kill(getpid(), SIGTERM); 316 return (void *) EXIT_SUCCESS; 317 318 out_fd: 319 close(fd); 320 out_socket: 321 object_unref(OBJECT(sioc)); 322 out: 323 g_free(info.name); 324 kill(getpid(), SIGTERM); 325 return (void *) EXIT_FAILURE; 326 } 327 #endif /* HAVE_NBD_DEVICE */ 328 329 static int nbd_can_accept(void) 330 { 331 return state == RUNNING && nb_fds < shared; 332 } 333 334 static void nbd_export_closed(NBDExport *export) 335 { 336 assert(state == TERMINATING); 337 state = TERMINATED; 338 } 339 340 static void nbd_update_server_watch(void); 341 342 static void nbd_client_closed(NBDClient *client, bool negotiated) 343 { 344 nb_fds--; 345 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 346 state = TERMINATE; 347 } 348 nbd_update_server_watch(); 349 nbd_client_put(client); 350 } 351 352 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 353 gpointer opaque) 354 { 355 if (state >= TERMINATE) { 356 return; 357 } 358 359 nb_fds++; 360 nbd_update_server_watch(); 361 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 362 } 363 364 static void nbd_update_server_watch(void) 365 { 366 if (nbd_can_accept()) { 367 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 368 } else { 369 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 370 } 371 } 372 373 374 static SocketAddress *nbd_build_socket_address(const char *sockpath, 375 const char *bindto, 376 const char *port) 377 { 378 SocketAddress *saddr; 379 380 saddr = g_new0(SocketAddress, 1); 381 if (sockpath) { 382 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 383 saddr->u.q_unix.path = g_strdup(sockpath); 384 } else { 385 InetSocketAddress *inet; 386 saddr->type = SOCKET_ADDRESS_TYPE_INET; 387 inet = &saddr->u.inet; 388 inet->host = g_strdup(bindto); 389 if (port) { 390 inet->port = g_strdup(port); 391 } else { 392 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 393 } 394 } 395 396 return saddr; 397 } 398 399 400 static QemuOptsList file_opts = { 401 .name = "file", 402 .implied_opt_name = "file", 403 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 404 .desc = { 405 /* no elements => accept any params */ 406 { /* end of list */ } 407 }, 408 }; 409 410 static QemuOptsList qemu_object_opts = { 411 .name = "object", 412 .implied_opt_name = "qom-type", 413 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 414 .desc = { 415 { } 416 }, 417 }; 418 419 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts) 420 { 421 if (user_creatable_print_help(type, opts)) { 422 exit(0); 423 } 424 return true; 425 } 426 427 428 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 429 Error **errp) 430 { 431 Object *obj; 432 QCryptoTLSCreds *creds; 433 434 obj = object_resolve_path_component( 435 object_get_objects_root(), id); 436 if (!obj) { 437 error_setg(errp, "No TLS credentials with id '%s'", 438 id); 439 return NULL; 440 } 441 creds = (QCryptoTLSCreds *) 442 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 443 if (!creds) { 444 error_setg(errp, "Object with id '%s' is not TLS credentials", 445 id); 446 return NULL; 447 } 448 449 if (list) { 450 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 451 error_setg(errp, 452 "Expecting TLS credentials with a client endpoint"); 453 return NULL; 454 } 455 } else { 456 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 457 error_setg(errp, 458 "Expecting TLS credentials with a server endpoint"); 459 return NULL; 460 } 461 } 462 object_ref(obj); 463 return creds; 464 } 465 466 static void setup_address_and_port(const char **address, const char **port) 467 { 468 if (*address == NULL) { 469 *address = "0.0.0.0"; 470 } 471 472 if (*port == NULL) { 473 *port = stringify(NBD_DEFAULT_PORT); 474 } 475 } 476 477 /* 478 * Check socket parameters compatibility when socket activation is used. 479 */ 480 static const char *socket_activation_validate_opts(const char *device, 481 const char *sockpath, 482 const char *address, 483 const char *port, 484 bool list) 485 { 486 if (device != NULL) { 487 return "NBD device can't be set when using socket activation"; 488 } 489 490 if (sockpath != NULL) { 491 return "Unix socket can't be set when using socket activation"; 492 } 493 494 if (address != NULL) { 495 return "The interface can't be set when using socket activation"; 496 } 497 498 if (port != NULL) { 499 return "TCP port number can't be set when using socket activation"; 500 } 501 502 if (list) { 503 return "List mode is incompatible with socket activation"; 504 } 505 506 return NULL; 507 } 508 509 static void qemu_nbd_shutdown(void) 510 { 511 job_cancel_sync_all(); 512 bdrv_close_all(); 513 } 514 515 int main(int argc, char **argv) 516 { 517 BlockBackend *blk; 518 BlockDriverState *bs; 519 uint64_t dev_offset = 0; 520 bool readonly = false; 521 bool disconnect = false; 522 const char *bindto = NULL; 523 const char *port = NULL; 524 char *sockpath = NULL; 525 char *device = NULL; 526 int64_t fd_size; 527 QemuOpts *sn_opts = NULL; 528 const char *sn_id_or_name = NULL; 529 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:B:L"; 530 struct option lopt[] = { 531 { "help", no_argument, NULL, 'h' }, 532 { "version", no_argument, NULL, 'V' }, 533 { "bind", required_argument, NULL, 'b' }, 534 { "port", required_argument, NULL, 'p' }, 535 { "socket", required_argument, NULL, 'k' }, 536 { "offset", required_argument, NULL, 'o' }, 537 { "read-only", no_argument, NULL, 'r' }, 538 { "bitmap", required_argument, NULL, 'B' }, 539 { "connect", required_argument, NULL, 'c' }, 540 { "disconnect", no_argument, NULL, 'd' }, 541 { "list", no_argument, NULL, 'L' }, 542 { "snapshot", no_argument, NULL, 's' }, 543 { "load-snapshot", required_argument, NULL, 'l' }, 544 { "nocache", no_argument, NULL, 'n' }, 545 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 546 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 547 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 548 { "detect-zeroes", required_argument, NULL, 549 QEMU_NBD_OPT_DETECT_ZEROES }, 550 { "shared", required_argument, NULL, 'e' }, 551 { "format", required_argument, NULL, 'f' }, 552 { "persistent", no_argument, NULL, 't' }, 553 { "verbose", no_argument, NULL, 'v' }, 554 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 555 { "export-name", required_argument, NULL, 'x' }, 556 { "description", required_argument, NULL, 'D' }, 557 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 558 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 559 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 560 { "trace", required_argument, NULL, 'T' }, 561 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 562 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 563 { NULL, 0, NULL, 0 } 564 }; 565 int ch; 566 int opt_ind = 0; 567 int flags = BDRV_O_RDWR; 568 int ret = 0; 569 bool seen_cache = false; 570 bool seen_discard = false; 571 bool seen_aio = false; 572 pthread_t client_thread; 573 const char *fmt = NULL; 574 Error *local_err = NULL; 575 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 576 QDict *options = NULL; 577 const char *export_name = NULL; /* defaults to "" later for server mode */ 578 const char *export_description = NULL; 579 const char *bitmap = NULL; 580 const char *tlscredsid = NULL; 581 bool imageOpts = false; 582 bool writethrough = true; 583 char *trace_file = NULL; 584 bool fork_process = false; 585 bool list = false; 586 int old_stderr = -1; 587 unsigned socket_activation; 588 const char *pid_file_name = NULL; 589 590 /* The client thread uses SIGTERM to interrupt the server. A signal 591 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 592 */ 593 struct sigaction sa_sigterm; 594 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 595 sa_sigterm.sa_handler = termsig_handler; 596 sigaction(SIGTERM, &sa_sigterm, NULL); 597 598 #ifdef CONFIG_POSIX 599 signal(SIGPIPE, SIG_IGN); 600 #endif 601 602 error_init(argv[0]); 603 module_call_init(MODULE_INIT_TRACE); 604 qcrypto_init(&error_fatal); 605 606 module_call_init(MODULE_INIT_QOM); 607 qemu_add_opts(&qemu_object_opts); 608 qemu_add_opts(&qemu_trace_opts); 609 qemu_init_exec_dir(argv[0]); 610 611 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 612 switch (ch) { 613 case 's': 614 flags |= BDRV_O_SNAPSHOT; 615 break; 616 case 'n': 617 optarg = (char *) "none"; 618 /* fallthrough */ 619 case QEMU_NBD_OPT_CACHE: 620 if (seen_cache) { 621 error_report("-n and --cache can only be specified once"); 622 exit(EXIT_FAILURE); 623 } 624 seen_cache = true; 625 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 626 error_report("Invalid cache mode `%s'", optarg); 627 exit(EXIT_FAILURE); 628 } 629 break; 630 case QEMU_NBD_OPT_AIO: 631 if (seen_aio) { 632 error_report("--aio can only be specified once"); 633 exit(EXIT_FAILURE); 634 } 635 seen_aio = true; 636 if (bdrv_parse_aio(optarg, &flags) < 0) { 637 error_report("Invalid aio mode '%s'", optarg); 638 exit(EXIT_FAILURE); 639 } 640 break; 641 case QEMU_NBD_OPT_DISCARD: 642 if (seen_discard) { 643 error_report("--discard can only be specified once"); 644 exit(EXIT_FAILURE); 645 } 646 seen_discard = true; 647 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 648 error_report("Invalid discard mode `%s'", optarg); 649 exit(EXIT_FAILURE); 650 } 651 break; 652 case QEMU_NBD_OPT_DETECT_ZEROES: 653 detect_zeroes = 654 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 655 optarg, 656 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 657 &local_err); 658 if (local_err) { 659 error_reportf_err(local_err, 660 "Failed to parse detect_zeroes mode: "); 661 exit(EXIT_FAILURE); 662 } 663 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 664 !(flags & BDRV_O_UNMAP)) { 665 error_report("setting detect-zeroes to unmap is not allowed " 666 "without setting discard operation to unmap"); 667 exit(EXIT_FAILURE); 668 } 669 break; 670 case 'b': 671 bindto = optarg; 672 break; 673 case 'p': 674 port = optarg; 675 break; 676 case 'o': 677 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 678 error_report("Invalid offset '%s'", optarg); 679 exit(EXIT_FAILURE); 680 } 681 break; 682 case 'l': 683 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 684 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 685 optarg, false); 686 if (!sn_opts) { 687 error_report("Failed in parsing snapshot param `%s'", 688 optarg); 689 exit(EXIT_FAILURE); 690 } 691 } else { 692 sn_id_or_name = optarg; 693 } 694 /* fall through */ 695 case 'r': 696 readonly = true; 697 flags &= ~BDRV_O_RDWR; 698 break; 699 case 'B': 700 bitmap = optarg; 701 break; 702 case 'k': 703 sockpath = optarg; 704 if (sockpath[0] != '/') { 705 error_report("socket path must be absolute"); 706 exit(EXIT_FAILURE); 707 } 708 break; 709 case 'd': 710 disconnect = true; 711 break; 712 case 'c': 713 device = optarg; 714 break; 715 case 'e': 716 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 717 shared < 1) { 718 error_report("Invalid shared device number '%s'", optarg); 719 exit(EXIT_FAILURE); 720 } 721 break; 722 case 'f': 723 fmt = optarg; 724 break; 725 case 't': 726 persistent = 1; 727 break; 728 case 'x': 729 export_name = optarg; 730 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 731 error_report("export name '%s' too long", export_name); 732 exit(EXIT_FAILURE); 733 } 734 break; 735 case 'D': 736 export_description = optarg; 737 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 738 error_report("export description '%s' too long", 739 export_description); 740 exit(EXIT_FAILURE); 741 } 742 break; 743 case 'v': 744 verbose = 1; 745 break; 746 case 'V': 747 version(argv[0]); 748 exit(0); 749 break; 750 case 'h': 751 usage(argv[0]); 752 exit(0); 753 break; 754 case '?': 755 error_report("Try `%s --help' for more information.", argv[0]); 756 exit(EXIT_FAILURE); 757 case QEMU_NBD_OPT_OBJECT: { 758 QemuOpts *opts; 759 opts = qemu_opts_parse_noisily(&qemu_object_opts, 760 optarg, true); 761 if (!opts) { 762 exit(EXIT_FAILURE); 763 } 764 } break; 765 case QEMU_NBD_OPT_TLSCREDS: 766 tlscredsid = optarg; 767 break; 768 case QEMU_NBD_OPT_IMAGE_OPTS: 769 imageOpts = true; 770 break; 771 case 'T': 772 g_free(trace_file); 773 trace_file = trace_opt_parse(optarg); 774 break; 775 case QEMU_NBD_OPT_TLSAUTHZ: 776 tlsauthz = optarg; 777 break; 778 case QEMU_NBD_OPT_FORK: 779 fork_process = true; 780 break; 781 case 'L': 782 list = true; 783 break; 784 case QEMU_NBD_OPT_PID_FILE: 785 pid_file_name = optarg; 786 break; 787 } 788 } 789 790 if (list) { 791 if (argc != optind) { 792 error_report("List mode is incompatible with a file name"); 793 exit(EXIT_FAILURE); 794 } 795 if (export_name || export_description || dev_offset || 796 device || disconnect || fmt || sn_id_or_name || bitmap || 797 seen_aio || seen_discard || seen_cache) { 798 error_report("List mode is incompatible with per-device settings"); 799 exit(EXIT_FAILURE); 800 } 801 if (fork_process) { 802 error_report("List mode is incompatible with forking"); 803 exit(EXIT_FAILURE); 804 } 805 } else if ((argc - optind) != 1) { 806 error_report("Invalid number of arguments"); 807 error_printf("Try `%s --help' for more information.\n", argv[0]); 808 exit(EXIT_FAILURE); 809 } else if (!export_name) { 810 export_name = ""; 811 } 812 813 qemu_opts_foreach(&qemu_object_opts, 814 user_creatable_add_opts_foreach, 815 qemu_nbd_object_print_help, &error_fatal); 816 817 if (!trace_init_backends()) { 818 exit(1); 819 } 820 trace_init_file(trace_file); 821 qemu_set_log(LOG_TRACE); 822 823 socket_activation = check_socket_activation(); 824 if (socket_activation == 0) { 825 setup_address_and_port(&bindto, &port); 826 } else { 827 /* Using socket activation - check user didn't use -p etc. */ 828 const char *err_msg = socket_activation_validate_opts(device, sockpath, 829 bindto, port, 830 list); 831 if (err_msg != NULL) { 832 error_report("%s", err_msg); 833 exit(EXIT_FAILURE); 834 } 835 836 /* qemu-nbd can only listen on a single socket. */ 837 if (socket_activation > 1) { 838 error_report("qemu-nbd does not support socket activation with %s > 1", 839 "LISTEN_FDS"); 840 exit(EXIT_FAILURE); 841 } 842 } 843 844 if (tlscredsid) { 845 if (sockpath) { 846 error_report("TLS is only supported with IPv4/IPv6"); 847 exit(EXIT_FAILURE); 848 } 849 if (device) { 850 error_report("TLS is not supported with a host device"); 851 exit(EXIT_FAILURE); 852 } 853 if (tlsauthz && list) { 854 error_report("TLS authorization is incompatible with export list"); 855 exit(EXIT_FAILURE); 856 } 857 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 858 if (local_err) { 859 error_reportf_err(local_err, "Failed to get TLS creds: "); 860 exit(EXIT_FAILURE); 861 } 862 } else { 863 if (tlsauthz) { 864 error_report("--tls-authz is not permitted without --tls-creds"); 865 exit(EXIT_FAILURE); 866 } 867 } 868 869 if (list) { 870 saddr = nbd_build_socket_address(sockpath, bindto, port); 871 return qemu_nbd_client_list(saddr, tlscreds, bindto); 872 } 873 874 #if !HAVE_NBD_DEVICE 875 if (disconnect || device) { 876 error_report("Kernel /dev/nbdN support not available"); 877 exit(EXIT_FAILURE); 878 } 879 #else /* HAVE_NBD_DEVICE */ 880 if (disconnect) { 881 int nbdfd = open(argv[optind], O_RDWR); 882 if (nbdfd < 0) { 883 error_report("Cannot open %s: %s", argv[optind], 884 strerror(errno)); 885 exit(EXIT_FAILURE); 886 } 887 nbd_disconnect(nbdfd); 888 889 close(nbdfd); 890 891 printf("%s disconnected\n", argv[optind]); 892 893 return 0; 894 } 895 #endif 896 897 if ((device && !verbose) || fork_process) { 898 int stderr_fd[2]; 899 pid_t pid; 900 int ret; 901 902 if (qemu_pipe(stderr_fd) < 0) { 903 error_report("Error setting up communication pipe: %s", 904 strerror(errno)); 905 exit(EXIT_FAILURE); 906 } 907 908 /* Now daemonize, but keep a communication channel open to 909 * print errors and exit with the proper status code. 910 */ 911 pid = fork(); 912 if (pid < 0) { 913 error_report("Failed to fork: %s", strerror(errno)); 914 exit(EXIT_FAILURE); 915 } else if (pid == 0) { 916 close(stderr_fd[0]); 917 918 /* Remember parent's stderr if we will be restoring it. */ 919 if (fork_process) { 920 old_stderr = dup(STDERR_FILENO); 921 } 922 923 ret = qemu_daemon(1, 0); 924 925 /* Temporarily redirect stderr to the parent's pipe... */ 926 dup2(stderr_fd[1], STDERR_FILENO); 927 if (ret < 0) { 928 error_report("Failed to daemonize: %s", strerror(errno)); 929 exit(EXIT_FAILURE); 930 } 931 932 /* ... close the descriptor we inherited and go on. */ 933 close(stderr_fd[1]); 934 } else { 935 bool errors = false; 936 char *buf; 937 938 /* In the parent. Print error messages from the child until 939 * it closes the pipe. 940 */ 941 close(stderr_fd[1]); 942 buf = g_malloc(1024); 943 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 944 errors = true; 945 ret = qemu_write_full(STDERR_FILENO, buf, ret); 946 if (ret < 0) { 947 exit(EXIT_FAILURE); 948 } 949 } 950 if (ret < 0) { 951 error_report("Cannot read from daemon: %s", 952 strerror(errno)); 953 exit(EXIT_FAILURE); 954 } 955 956 /* Usually the daemon should not print any message. 957 * Exit with zero status in that case. 958 */ 959 exit(errors); 960 } 961 } 962 963 if (device != NULL && sockpath == NULL) { 964 sockpath = g_malloc(128); 965 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 966 } 967 968 server = qio_net_listener_new(); 969 if (socket_activation == 0) { 970 saddr = nbd_build_socket_address(sockpath, bindto, port); 971 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) { 972 object_unref(OBJECT(server)); 973 error_report_err(local_err); 974 exit(EXIT_FAILURE); 975 } 976 } else { 977 size_t i; 978 /* See comment in check_socket_activation above. */ 979 for (i = 0; i < socket_activation; i++) { 980 QIOChannelSocket *sioc; 981 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 982 &local_err); 983 if (sioc == NULL) { 984 object_unref(OBJECT(server)); 985 error_reportf_err(local_err, 986 "Failed to use socket activation: "); 987 exit(EXIT_FAILURE); 988 } 989 qio_net_listener_add(server, sioc); 990 object_unref(OBJECT(sioc)); 991 } 992 } 993 994 if (qemu_init_main_loop(&local_err)) { 995 error_report_err(local_err); 996 exit(EXIT_FAILURE); 997 } 998 bdrv_init(); 999 atexit(qemu_nbd_shutdown); 1000 1001 srcpath = argv[optind]; 1002 if (imageOpts) { 1003 QemuOpts *opts; 1004 if (fmt) { 1005 error_report("--image-opts and -f are mutually exclusive"); 1006 exit(EXIT_FAILURE); 1007 } 1008 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1009 if (!opts) { 1010 qemu_opts_reset(&file_opts); 1011 exit(EXIT_FAILURE); 1012 } 1013 options = qemu_opts_to_qdict(opts, NULL); 1014 qemu_opts_reset(&file_opts); 1015 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1016 } else { 1017 if (fmt) { 1018 options = qdict_new(); 1019 qdict_put_str(options, "driver", fmt); 1020 } 1021 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1022 } 1023 1024 if (!blk) { 1025 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1026 argv[optind]); 1027 exit(EXIT_FAILURE); 1028 } 1029 bs = blk_bs(blk); 1030 1031 blk_set_enable_write_cache(blk, !writethrough); 1032 1033 if (sn_opts) { 1034 ret = bdrv_snapshot_load_tmp(bs, 1035 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1036 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1037 &local_err); 1038 } else if (sn_id_or_name) { 1039 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1040 &local_err); 1041 } 1042 if (ret < 0) { 1043 error_reportf_err(local_err, "Failed to load snapshot: "); 1044 exit(EXIT_FAILURE); 1045 } 1046 1047 bs->detect_zeroes = detect_zeroes; 1048 fd_size = blk_getlength(blk); 1049 if (fd_size < 0) { 1050 error_report("Failed to determine the image length: %s", 1051 strerror(-fd_size)); 1052 exit(EXIT_FAILURE); 1053 } 1054 1055 if (dev_offset >= fd_size) { 1056 error_report("Offset (%" PRIu64 ") has to be smaller than the image " 1057 "size (%" PRId64 ")", dev_offset, fd_size); 1058 exit(EXIT_FAILURE); 1059 } 1060 fd_size -= dev_offset; 1061 1062 export = nbd_export_new(bs, dev_offset, fd_size, export_name, 1063 export_description, bitmap, readonly, shared > 1, 1064 nbd_export_closed, writethrough, NULL, 1065 &error_fatal); 1066 1067 if (device) { 1068 #if HAVE_NBD_DEVICE 1069 int ret; 1070 1071 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1072 if (ret != 0) { 1073 error_report("Failed to create client thread: %s", strerror(ret)); 1074 exit(EXIT_FAILURE); 1075 } 1076 #endif 1077 } else { 1078 /* Shut up GCC warnings. */ 1079 memset(&client_thread, 0, sizeof(client_thread)); 1080 } 1081 1082 nbd_update_server_watch(); 1083 1084 if (pid_file_name) { 1085 qemu_write_pidfile(pid_file_name, &error_fatal); 1086 } 1087 1088 /* now when the initialization is (almost) complete, chdir("/") 1089 * to free any busy filesystems */ 1090 if (chdir("/") < 0) { 1091 error_report("Could not chdir to root directory: %s", 1092 strerror(errno)); 1093 exit(EXIT_FAILURE); 1094 } 1095 1096 if (fork_process) { 1097 dup2(old_stderr, STDERR_FILENO); 1098 close(old_stderr); 1099 } 1100 1101 state = RUNNING; 1102 do { 1103 main_loop_wait(false); 1104 if (state == TERMINATE) { 1105 state = TERMINATING; 1106 nbd_export_close(export); 1107 nbd_export_put(export); 1108 export = NULL; 1109 } 1110 } while (state != TERMINATED); 1111 1112 blk_unref(blk); 1113 if (sockpath) { 1114 unlink(sockpath); 1115 } 1116 1117 qemu_opts_del(sn_opts); 1118 1119 if (device) { 1120 void *ret; 1121 pthread_join(client_thread, &ret); 1122 exit(ret != NULL); 1123 } else { 1124 exit(EXIT_SUCCESS); 1125 } 1126 } 1127