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 int verbose; 69 static char *srcpath; 70 static SocketAddress *saddr; 71 static int persistent = 0; 72 static enum { RUNNING, TERMINATE, TERMINATED } state; 73 static int shared = 1; 74 static int nb_fds; 75 static QIONetListener *server; 76 static QCryptoTLSCreds *tlscreds; 77 static const char *tlsauthz; 78 79 static void usage(const char *name) 80 { 81 (printf) ( 82 "Usage: %s [OPTIONS] FILE\n" 83 " or: %s -L [OPTIONS]\n" 84 "QEMU Disk Network Block Device Utility\n" 85 "\n" 86 " -h, --help display this help and exit\n" 87 " -V, --version output version information and exit\n" 88 "\n" 89 "Connection properties:\n" 90 " -p, --port=PORT port to listen on (default `%d')\n" 91 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 92 " -k, --socket=PATH path to the unix socket\n" 93 " (default '"SOCKET_PATH"')\n" 94 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 95 " -t, --persistent don't exit on the last connection\n" 96 " -v, --verbose display extra debugging information\n" 97 " -x, --export-name=NAME expose export by name (default is empty string)\n" 98 " -D, --description=TEXT export a human-readable description\n" 99 "\n" 100 "Exposing part of the image:\n" 101 " -o, --offset=OFFSET offset into the image\n" 102 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 103 "\n" 104 "General purpose options:\n" 105 " -L, --list list exports available from another NBD server\n" 106 " --object type,id=ID,... define an object such as 'secret' for providing\n" 107 " passwords and/or encryption keys\n" 108 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 109 " --tls-authz=ID use id of an earlier --object to provide\n" 110 " authorization\n" 111 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 112 " specify tracing options\n" 113 " --fork fork off the server process and exit the parent\n" 114 " once the server is running\n" 115 " --pid-file=PATH store the server's process ID in the given file\n" 116 #if HAVE_NBD_DEVICE 117 "\n" 118 "Kernel NBD client support:\n" 119 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 120 " -d, --disconnect disconnect the specified device\n" 121 #endif 122 "\n" 123 "Block device options:\n" 124 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 125 " -r, --read-only export read-only\n" 126 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 127 " file with backing_file=FILE, redirect the write to\n" 128 " the temporary one\n" 129 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 130 " load an internal snapshot inside FILE and export it\n" 131 " as an read-only device, SNAPSHOT_PARAM format is\n" 132 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 133 " '[ID_OR_NAME]'\n" 134 " -n, --nocache disable host cache\n" 135 " --cache=MODE set cache mode (none, writeback, ...)\n" 136 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 137 " --discard=MODE set discard mode (ignore, unmap)\n" 138 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 139 " --image-opts treat FILE as a full set of image options\n" 140 "\n" 141 QEMU_HELP_BOTTOM "\n" 142 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 143 } 144 145 static void version(const char *name) 146 { 147 printf( 148 "%s " QEMU_FULL_VERSION "\n" 149 "Written by Anthony Liguori.\n" 150 "\n" 151 QEMU_COPYRIGHT "\n" 152 "This is free software; see the source for copying conditions. There is NO\n" 153 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 154 , name); 155 } 156 157 #ifdef CONFIG_POSIX 158 static void termsig_handler(int signum) 159 { 160 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 161 qemu_notify_event(); 162 } 163 #endif /* CONFIG_POSIX */ 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_update_server_watch(void); 335 336 static void nbd_client_closed(NBDClient *client, bool negotiated) 337 { 338 nb_fds--; 339 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 340 state = TERMINATE; 341 } 342 nbd_update_server_watch(); 343 nbd_client_put(client); 344 } 345 346 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 347 gpointer opaque) 348 { 349 if (state >= TERMINATE) { 350 return; 351 } 352 353 nb_fds++; 354 nbd_update_server_watch(); 355 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 356 } 357 358 static void nbd_update_server_watch(void) 359 { 360 if (nbd_can_accept()) { 361 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 362 } else { 363 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 364 } 365 } 366 367 368 static SocketAddress *nbd_build_socket_address(const char *sockpath, 369 const char *bindto, 370 const char *port) 371 { 372 SocketAddress *saddr; 373 374 saddr = g_new0(SocketAddress, 1); 375 if (sockpath) { 376 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 377 saddr->u.q_unix.path = g_strdup(sockpath); 378 } else { 379 InetSocketAddress *inet; 380 saddr->type = SOCKET_ADDRESS_TYPE_INET; 381 inet = &saddr->u.inet; 382 inet->host = g_strdup(bindto); 383 if (port) { 384 inet->port = g_strdup(port); 385 } else { 386 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 387 } 388 } 389 390 return saddr; 391 } 392 393 394 static QemuOptsList file_opts = { 395 .name = "file", 396 .implied_opt_name = "file", 397 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 398 .desc = { 399 /* no elements => accept any params */ 400 { /* end of list */ } 401 }, 402 }; 403 404 static QemuOptsList qemu_object_opts = { 405 .name = "object", 406 .implied_opt_name = "qom-type", 407 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 408 .desc = { 409 { } 410 }, 411 }; 412 413 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts) 414 { 415 if (user_creatable_print_help(type, opts)) { 416 exit(0); 417 } 418 return true; 419 } 420 421 422 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 423 Error **errp) 424 { 425 Object *obj; 426 QCryptoTLSCreds *creds; 427 428 obj = object_resolve_path_component( 429 object_get_objects_root(), id); 430 if (!obj) { 431 error_setg(errp, "No TLS credentials with id '%s'", 432 id); 433 return NULL; 434 } 435 creds = (QCryptoTLSCreds *) 436 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 437 if (!creds) { 438 error_setg(errp, "Object with id '%s' is not TLS credentials", 439 id); 440 return NULL; 441 } 442 443 if (list) { 444 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 445 error_setg(errp, 446 "Expecting TLS credentials with a client endpoint"); 447 return NULL; 448 } 449 } else { 450 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 451 error_setg(errp, 452 "Expecting TLS credentials with a server endpoint"); 453 return NULL; 454 } 455 } 456 object_ref(obj); 457 return creds; 458 } 459 460 static void setup_address_and_port(const char **address, const char **port) 461 { 462 if (*address == NULL) { 463 *address = "0.0.0.0"; 464 } 465 466 if (*port == NULL) { 467 *port = stringify(NBD_DEFAULT_PORT); 468 } 469 } 470 471 /* 472 * Check socket parameters compatibility when socket activation is used. 473 */ 474 static const char *socket_activation_validate_opts(const char *device, 475 const char *sockpath, 476 const char *address, 477 const char *port, 478 bool list) 479 { 480 if (device != NULL) { 481 return "NBD device can't be set when using socket activation"; 482 } 483 484 if (sockpath != NULL) { 485 return "Unix socket can't be set when using socket activation"; 486 } 487 488 if (address != NULL) { 489 return "The interface can't be set when using socket activation"; 490 } 491 492 if (port != NULL) { 493 return "TCP port number can't be set when using socket activation"; 494 } 495 496 if (list) { 497 return "List mode is incompatible with socket activation"; 498 } 499 500 return NULL; 501 } 502 503 static void qemu_nbd_shutdown(void) 504 { 505 job_cancel_sync_all(); 506 bdrv_close_all(); 507 } 508 509 int main(int argc, char **argv) 510 { 511 BlockBackend *blk; 512 BlockDriverState *bs; 513 uint64_t dev_offset = 0; 514 bool readonly = false; 515 bool disconnect = false; 516 const char *bindto = NULL; 517 const char *port = NULL; 518 char *sockpath = NULL; 519 char *device = NULL; 520 QemuOpts *sn_opts = NULL; 521 const char *sn_id_or_name = NULL; 522 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:B:L"; 523 struct option lopt[] = { 524 { "help", no_argument, NULL, 'h' }, 525 { "version", no_argument, NULL, 'V' }, 526 { "bind", required_argument, NULL, 'b' }, 527 { "port", required_argument, NULL, 'p' }, 528 { "socket", required_argument, NULL, 'k' }, 529 { "offset", required_argument, NULL, 'o' }, 530 { "read-only", no_argument, NULL, 'r' }, 531 { "bitmap", required_argument, NULL, 'B' }, 532 { "connect", required_argument, NULL, 'c' }, 533 { "disconnect", no_argument, NULL, 'd' }, 534 { "list", no_argument, NULL, 'L' }, 535 { "snapshot", no_argument, NULL, 's' }, 536 { "load-snapshot", required_argument, NULL, 'l' }, 537 { "nocache", no_argument, NULL, 'n' }, 538 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 539 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 540 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 541 { "detect-zeroes", required_argument, NULL, 542 QEMU_NBD_OPT_DETECT_ZEROES }, 543 { "shared", required_argument, NULL, 'e' }, 544 { "format", required_argument, NULL, 'f' }, 545 { "persistent", no_argument, NULL, 't' }, 546 { "verbose", no_argument, NULL, 'v' }, 547 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 548 { "export-name", required_argument, NULL, 'x' }, 549 { "description", required_argument, NULL, 'D' }, 550 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 551 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 552 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 553 { "trace", required_argument, NULL, 'T' }, 554 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 555 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 556 { NULL, 0, NULL, 0 } 557 }; 558 int ch; 559 int opt_ind = 0; 560 int flags = BDRV_O_RDWR; 561 int ret = 0; 562 bool seen_cache = false; 563 bool seen_discard = false; 564 bool seen_aio = false; 565 pthread_t client_thread; 566 const char *fmt = NULL; 567 Error *local_err = NULL; 568 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 569 QDict *options = NULL; 570 const char *export_name = NULL; /* defaults to "" later for server mode */ 571 const char *export_description = NULL; 572 const char *bitmap = NULL; 573 const char *tlscredsid = NULL; 574 bool imageOpts = false; 575 bool writethrough = true; 576 char *trace_file = NULL; 577 bool fork_process = false; 578 bool list = false; 579 int old_stderr = -1; 580 unsigned socket_activation; 581 const char *pid_file_name = NULL; 582 BlockExportOptions *export_opts; 583 584 #ifdef CONFIG_POSIX 585 /* 586 * Exit gracefully on various signals, which includes SIGTERM used 587 * by 'qemu-nbd -v -c'. 588 */ 589 struct sigaction sa_sigterm; 590 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 591 sa_sigterm.sa_handler = termsig_handler; 592 sigaction(SIGTERM, &sa_sigterm, NULL); 593 sigaction(SIGINT, &sa_sigterm, NULL); 594 sigaction(SIGHUP, &sa_sigterm, NULL); 595 596 signal(SIGPIPE, SIG_IGN); 597 #endif 598 599 socket_init(); 600 error_init(argv[0]); 601 module_call_init(MODULE_INIT_TRACE); 602 qcrypto_init(&error_fatal); 603 604 module_call_init(MODULE_INIT_QOM); 605 qemu_add_opts(&qemu_object_opts); 606 qemu_add_opts(&qemu_trace_opts); 607 qemu_init_exec_dir(argv[0]); 608 609 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 610 switch (ch) { 611 case 's': 612 flags |= BDRV_O_SNAPSHOT; 613 break; 614 case 'n': 615 optarg = (char *) "none"; 616 /* fallthrough */ 617 case QEMU_NBD_OPT_CACHE: 618 if (seen_cache) { 619 error_report("-n and --cache can only be specified once"); 620 exit(EXIT_FAILURE); 621 } 622 seen_cache = true; 623 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 624 error_report("Invalid cache mode `%s'", optarg); 625 exit(EXIT_FAILURE); 626 } 627 break; 628 case QEMU_NBD_OPT_AIO: 629 if (seen_aio) { 630 error_report("--aio can only be specified once"); 631 exit(EXIT_FAILURE); 632 } 633 seen_aio = true; 634 if (bdrv_parse_aio(optarg, &flags) < 0) { 635 error_report("Invalid aio mode '%s'", optarg); 636 exit(EXIT_FAILURE); 637 } 638 break; 639 case QEMU_NBD_OPT_DISCARD: 640 if (seen_discard) { 641 error_report("--discard can only be specified once"); 642 exit(EXIT_FAILURE); 643 } 644 seen_discard = true; 645 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 646 error_report("Invalid discard mode `%s'", optarg); 647 exit(EXIT_FAILURE); 648 } 649 break; 650 case QEMU_NBD_OPT_DETECT_ZEROES: 651 detect_zeroes = 652 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 653 optarg, 654 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 655 &local_err); 656 if (local_err) { 657 error_reportf_err(local_err, 658 "Failed to parse detect_zeroes mode: "); 659 exit(EXIT_FAILURE); 660 } 661 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 662 !(flags & BDRV_O_UNMAP)) { 663 error_report("setting detect-zeroes to unmap is not allowed " 664 "without setting discard operation to unmap"); 665 exit(EXIT_FAILURE); 666 } 667 break; 668 case 'b': 669 bindto = optarg; 670 break; 671 case 'p': 672 port = optarg; 673 break; 674 case 'o': 675 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 676 error_report("Invalid offset '%s'", optarg); 677 exit(EXIT_FAILURE); 678 } 679 break; 680 case 'l': 681 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 682 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 683 optarg, false); 684 if (!sn_opts) { 685 error_report("Failed in parsing snapshot param `%s'", 686 optarg); 687 exit(EXIT_FAILURE); 688 } 689 } else { 690 sn_id_or_name = optarg; 691 } 692 /* fall through */ 693 case 'r': 694 readonly = true; 695 flags &= ~BDRV_O_RDWR; 696 break; 697 case 'B': 698 bitmap = optarg; 699 break; 700 case 'k': 701 sockpath = optarg; 702 if (sockpath[0] != '/') { 703 error_report("socket path must be absolute"); 704 exit(EXIT_FAILURE); 705 } 706 break; 707 case 'd': 708 disconnect = true; 709 break; 710 case 'c': 711 device = optarg; 712 break; 713 case 'e': 714 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 715 shared < 1) { 716 error_report("Invalid shared device number '%s'", optarg); 717 exit(EXIT_FAILURE); 718 } 719 break; 720 case 'f': 721 fmt = optarg; 722 break; 723 case 't': 724 persistent = 1; 725 break; 726 case 'x': 727 export_name = optarg; 728 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 729 error_report("export name '%s' too long", export_name); 730 exit(EXIT_FAILURE); 731 } 732 break; 733 case 'D': 734 export_description = optarg; 735 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 736 error_report("export description '%s' too long", 737 export_description); 738 exit(EXIT_FAILURE); 739 } 740 break; 741 case 'v': 742 verbose = 1; 743 break; 744 case 'V': 745 version(argv[0]); 746 exit(0); 747 break; 748 case 'h': 749 usage(argv[0]); 750 exit(0); 751 break; 752 case '?': 753 error_report("Try `%s --help' for more information.", argv[0]); 754 exit(EXIT_FAILURE); 755 case QEMU_NBD_OPT_OBJECT: { 756 QemuOpts *opts; 757 opts = qemu_opts_parse_noisily(&qemu_object_opts, 758 optarg, true); 759 if (!opts) { 760 exit(EXIT_FAILURE); 761 } 762 } break; 763 case QEMU_NBD_OPT_TLSCREDS: 764 tlscredsid = optarg; 765 break; 766 case QEMU_NBD_OPT_IMAGE_OPTS: 767 imageOpts = true; 768 break; 769 case 'T': 770 g_free(trace_file); 771 trace_file = trace_opt_parse(optarg); 772 break; 773 case QEMU_NBD_OPT_TLSAUTHZ: 774 tlsauthz = optarg; 775 break; 776 case QEMU_NBD_OPT_FORK: 777 fork_process = true; 778 break; 779 case 'L': 780 list = true; 781 break; 782 case QEMU_NBD_OPT_PID_FILE: 783 pid_file_name = optarg; 784 break; 785 } 786 } 787 788 if (list) { 789 if (argc != optind) { 790 error_report("List mode is incompatible with a file name"); 791 exit(EXIT_FAILURE); 792 } 793 if (export_name || export_description || dev_offset || 794 device || disconnect || fmt || sn_id_or_name || bitmap || 795 seen_aio || seen_discard || seen_cache) { 796 error_report("List mode is incompatible with per-device settings"); 797 exit(EXIT_FAILURE); 798 } 799 if (fork_process) { 800 error_report("List mode is incompatible with forking"); 801 exit(EXIT_FAILURE); 802 } 803 } else if ((argc - optind) != 1) { 804 error_report("Invalid number of arguments"); 805 error_printf("Try `%s --help' for more information.\n", argv[0]); 806 exit(EXIT_FAILURE); 807 } else if (!export_name) { 808 export_name = ""; 809 } 810 811 qemu_opts_foreach(&qemu_object_opts, 812 user_creatable_add_opts_foreach, 813 qemu_nbd_object_print_help, &error_fatal); 814 815 if (!trace_init_backends()) { 816 exit(1); 817 } 818 trace_init_file(trace_file); 819 qemu_set_log(LOG_TRACE); 820 821 socket_activation = check_socket_activation(); 822 if (socket_activation == 0) { 823 setup_address_and_port(&bindto, &port); 824 } else { 825 /* Using socket activation - check user didn't use -p etc. */ 826 const char *err_msg = socket_activation_validate_opts(device, sockpath, 827 bindto, port, 828 list); 829 if (err_msg != NULL) { 830 error_report("%s", err_msg); 831 exit(EXIT_FAILURE); 832 } 833 834 /* qemu-nbd can only listen on a single socket. */ 835 if (socket_activation > 1) { 836 error_report("qemu-nbd does not support socket activation with %s > 1", 837 "LISTEN_FDS"); 838 exit(EXIT_FAILURE); 839 } 840 } 841 842 if (tlscredsid) { 843 if (sockpath) { 844 error_report("TLS is only supported with IPv4/IPv6"); 845 exit(EXIT_FAILURE); 846 } 847 if (device) { 848 error_report("TLS is not supported with a host device"); 849 exit(EXIT_FAILURE); 850 } 851 if (tlsauthz && list) { 852 error_report("TLS authorization is incompatible with export list"); 853 exit(EXIT_FAILURE); 854 } 855 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 856 if (local_err) { 857 error_reportf_err(local_err, "Failed to get TLS creds: "); 858 exit(EXIT_FAILURE); 859 } 860 } else { 861 if (tlsauthz) { 862 error_report("--tls-authz is not permitted without --tls-creds"); 863 exit(EXIT_FAILURE); 864 } 865 } 866 867 if (list) { 868 saddr = nbd_build_socket_address(sockpath, bindto, port); 869 return qemu_nbd_client_list(saddr, tlscreds, bindto); 870 } 871 872 #if !HAVE_NBD_DEVICE 873 if (disconnect || device) { 874 error_report("Kernel /dev/nbdN support not available"); 875 exit(EXIT_FAILURE); 876 } 877 #else /* HAVE_NBD_DEVICE */ 878 if (disconnect) { 879 int nbdfd = open(argv[optind], O_RDWR); 880 if (nbdfd < 0) { 881 error_report("Cannot open %s: %s", argv[optind], 882 strerror(errno)); 883 exit(EXIT_FAILURE); 884 } 885 nbd_disconnect(nbdfd); 886 887 close(nbdfd); 888 889 printf("%s disconnected\n", argv[optind]); 890 891 return 0; 892 } 893 #endif 894 895 if ((device && !verbose) || fork_process) { 896 #ifndef WIN32 897 int stderr_fd[2]; 898 pid_t pid; 899 int ret; 900 901 if (qemu_pipe(stderr_fd) < 0) { 902 error_report("Error setting up communication pipe: %s", 903 strerror(errno)); 904 exit(EXIT_FAILURE); 905 } 906 907 /* Now daemonize, but keep a communication channel open to 908 * print errors and exit with the proper status code. 909 */ 910 pid = fork(); 911 if (pid < 0) { 912 error_report("Failed to fork: %s", strerror(errno)); 913 exit(EXIT_FAILURE); 914 } else if (pid == 0) { 915 close(stderr_fd[0]); 916 917 /* Remember parent's stderr if we will be restoring it. */ 918 if (fork_process) { 919 old_stderr = dup(STDERR_FILENO); 920 } 921 922 ret = qemu_daemon(1, 0); 923 924 /* Temporarily redirect stderr to the parent's pipe... */ 925 dup2(stderr_fd[1], STDERR_FILENO); 926 if (ret < 0) { 927 error_report("Failed to daemonize: %s", strerror(errno)); 928 exit(EXIT_FAILURE); 929 } 930 931 /* ... close the descriptor we inherited and go on. */ 932 close(stderr_fd[1]); 933 } else { 934 bool errors = false; 935 char *buf; 936 937 /* In the parent. Print error messages from the child until 938 * it closes the pipe. 939 */ 940 close(stderr_fd[1]); 941 buf = g_malloc(1024); 942 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 943 errors = true; 944 ret = qemu_write_full(STDERR_FILENO, buf, ret); 945 if (ret < 0) { 946 exit(EXIT_FAILURE); 947 } 948 } 949 if (ret < 0) { 950 error_report("Cannot read from daemon: %s", 951 strerror(errno)); 952 exit(EXIT_FAILURE); 953 } 954 955 /* Usually the daemon should not print any message. 956 * Exit with zero status in that case. 957 */ 958 exit(errors); 959 } 960 #else /* WIN32 */ 961 error_report("Unable to fork into background on Windows hosts"); 962 exit(EXIT_FAILURE); 963 #endif /* WIN32 */ 964 } 965 966 if (device != NULL && sockpath == NULL) { 967 sockpath = g_malloc(128); 968 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 969 } 970 971 server = qio_net_listener_new(); 972 if (socket_activation == 0) { 973 saddr = nbd_build_socket_address(sockpath, bindto, port); 974 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) { 975 object_unref(OBJECT(server)); 976 error_report_err(local_err); 977 exit(EXIT_FAILURE); 978 } 979 } else { 980 size_t i; 981 /* See comment in check_socket_activation above. */ 982 for (i = 0; i < socket_activation; i++) { 983 QIOChannelSocket *sioc; 984 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 985 &local_err); 986 if (sioc == NULL) { 987 object_unref(OBJECT(server)); 988 error_reportf_err(local_err, 989 "Failed to use socket activation: "); 990 exit(EXIT_FAILURE); 991 } 992 qio_net_listener_add(server, sioc); 993 object_unref(OBJECT(sioc)); 994 } 995 } 996 997 if (qemu_init_main_loop(&local_err)) { 998 error_report_err(local_err); 999 exit(EXIT_FAILURE); 1000 } 1001 bdrv_init(); 1002 atexit(qemu_nbd_shutdown); 1003 1004 srcpath = argv[optind]; 1005 if (imageOpts) { 1006 QemuOpts *opts; 1007 if (fmt) { 1008 error_report("--image-opts and -f are mutually exclusive"); 1009 exit(EXIT_FAILURE); 1010 } 1011 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1012 if (!opts) { 1013 qemu_opts_reset(&file_opts); 1014 exit(EXIT_FAILURE); 1015 } 1016 options = qemu_opts_to_qdict(opts, NULL); 1017 qemu_opts_reset(&file_opts); 1018 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1019 } else { 1020 if (fmt) { 1021 options = qdict_new(); 1022 qdict_put_str(options, "driver", fmt); 1023 } 1024 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1025 } 1026 1027 if (!blk) { 1028 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1029 argv[optind]); 1030 exit(EXIT_FAILURE); 1031 } 1032 bs = blk_bs(blk); 1033 1034 if (dev_offset) { 1035 QDict *raw_opts = qdict_new(); 1036 qdict_put_str(raw_opts, "driver", "raw"); 1037 qdict_put_str(raw_opts, "file", bs->node_name); 1038 qdict_put_int(raw_opts, "offset", dev_offset); 1039 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1040 blk_remove_bs(blk); 1041 blk_insert_bs(blk, bs, &error_fatal); 1042 bdrv_unref(bs); 1043 } 1044 1045 blk_set_enable_write_cache(blk, !writethrough); 1046 1047 if (sn_opts) { 1048 ret = bdrv_snapshot_load_tmp(bs, 1049 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1050 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1051 &local_err); 1052 } else if (sn_id_or_name) { 1053 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1054 &local_err); 1055 } 1056 if (ret < 0) { 1057 error_reportf_err(local_err, "Failed to load snapshot: "); 1058 exit(EXIT_FAILURE); 1059 } 1060 1061 bs->detect_zeroes = detect_zeroes; 1062 1063 nbd_server_is_qemu_nbd(true); 1064 1065 export_opts = g_new(BlockExportOptions, 1); 1066 *export_opts = (BlockExportOptions) { 1067 .type = BLOCK_EXPORT_TYPE_NBD, 1068 .id = g_strdup("qemu-nbd-export"), 1069 .node_name = g_strdup(bdrv_get_node_name(bs)), 1070 .has_writethrough = true, 1071 .writethrough = writethrough, 1072 .has_writable = true, 1073 .writable = !readonly, 1074 .u.nbd = { 1075 .has_name = true, 1076 .name = g_strdup(export_name), 1077 .has_description = !!export_description, 1078 .description = g_strdup(export_description), 1079 .has_bitmap = !!bitmap, 1080 .bitmap = g_strdup(bitmap), 1081 }, 1082 }; 1083 blk_exp_add(export_opts, &error_fatal); 1084 qapi_free_BlockExportOptions(export_opts); 1085 1086 if (device) { 1087 #if HAVE_NBD_DEVICE 1088 int ret; 1089 1090 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1091 if (ret != 0) { 1092 error_report("Failed to create client thread: %s", strerror(ret)); 1093 exit(EXIT_FAILURE); 1094 } 1095 #endif 1096 } else { 1097 /* Shut up GCC warnings. */ 1098 memset(&client_thread, 0, sizeof(client_thread)); 1099 } 1100 1101 nbd_update_server_watch(); 1102 1103 if (pid_file_name) { 1104 qemu_write_pidfile(pid_file_name, &error_fatal); 1105 } 1106 1107 /* now when the initialization is (almost) complete, chdir("/") 1108 * to free any busy filesystems */ 1109 if (chdir("/") < 0) { 1110 error_report("Could not chdir to root directory: %s", 1111 strerror(errno)); 1112 exit(EXIT_FAILURE); 1113 } 1114 1115 if (fork_process) { 1116 dup2(old_stderr, STDERR_FILENO); 1117 close(old_stderr); 1118 } 1119 1120 state = RUNNING; 1121 do { 1122 main_loop_wait(false); 1123 if (state == TERMINATE) { 1124 blk_exp_close_all(); 1125 state = TERMINATED; 1126 } 1127 } while (state != TERMINATED); 1128 1129 blk_unref(blk); 1130 if (sockpath) { 1131 unlink(sockpath); 1132 } 1133 1134 qemu_opts_del(sn_opts); 1135 1136 if (device) { 1137 void *ret; 1138 pthread_join(client_thread, &ret); 1139 exit(ret != NULL); 1140 } else { 1141 exit(EXIT_SUCCESS); 1142 } 1143 } 1144