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 #if HAVE_NBD_DEVICE 159 static void termsig_handler(int signum) 160 { 161 atomic_cmpxchg(&state, RUNNING, TERMINATE); 162 qemu_notify_event(); 163 } 164 #endif /* HAVE_NBD_DEVICE */ 165 166 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 167 const char *hostname) 168 { 169 int ret = EXIT_FAILURE; 170 int rc; 171 Error *err = NULL; 172 QIOChannelSocket *sioc; 173 NBDExportInfo *list; 174 int i, j; 175 176 sioc = qio_channel_socket_new(); 177 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 178 error_report_err(err); 179 return EXIT_FAILURE; 180 } 181 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 182 &err); 183 if (rc < 0) { 184 if (err) { 185 error_report_err(err); 186 } 187 goto out; 188 } 189 printf("exports available: %d\n", rc); 190 for (i = 0; i < rc; i++) { 191 printf(" export: '%s'\n", list[i].name); 192 if (list[i].description && *list[i].description) { 193 printf(" description: %s\n", list[i].description); 194 } 195 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 196 static const char *const flag_names[] = { 197 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 198 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 199 [NBD_FLAG_SEND_FUA_BIT] = "fua", 200 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 201 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 202 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 203 [NBD_FLAG_SEND_DF_BIT] = "df", 204 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 205 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 206 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 207 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 208 }; 209 210 printf(" size: %" PRIu64 "\n", list[i].size); 211 printf(" flags: 0x%x (", list[i].flags); 212 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 213 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 214 printf(" %s", flag_names[bit]); 215 } 216 } 217 printf(" )\n"); 218 } 219 if (list[i].min_block) { 220 printf(" min block: %u\n", list[i].min_block); 221 printf(" opt block: %u\n", list[i].opt_block); 222 printf(" max block: %u\n", list[i].max_block); 223 } 224 if (list[i].n_contexts) { 225 printf(" available meta contexts: %d\n", list[i].n_contexts); 226 for (j = 0; j < list[i].n_contexts; j++) { 227 printf(" %s\n", list[i].contexts[j]); 228 } 229 } 230 } 231 nbd_free_export_list(list, rc); 232 233 ret = EXIT_SUCCESS; 234 out: 235 object_unref(OBJECT(sioc)); 236 return ret; 237 } 238 239 240 #if HAVE_NBD_DEVICE 241 static void *show_parts(void *arg) 242 { 243 char *device = arg; 244 int nbd; 245 246 /* linux just needs an open() to trigger 247 * the partition table update 248 * but remember to load the module with max_part != 0 : 249 * modprobe nbd max_part=63 250 */ 251 nbd = open(device, O_RDWR); 252 if (nbd >= 0) { 253 close(nbd); 254 } 255 return NULL; 256 } 257 258 static void *nbd_client_thread(void *arg) 259 { 260 char *device = arg; 261 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 262 QIOChannelSocket *sioc; 263 int fd; 264 int ret; 265 pthread_t show_parts_thread; 266 Error *local_error = NULL; 267 268 sioc = qio_channel_socket_new(); 269 if (qio_channel_socket_connect_sync(sioc, 270 saddr, 271 &local_error) < 0) { 272 error_report_err(local_error); 273 goto out; 274 } 275 276 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 277 NULL, NULL, NULL, &info, &local_error); 278 if (ret < 0) { 279 if (local_error) { 280 error_report_err(local_error); 281 } 282 goto out_socket; 283 } 284 285 fd = open(device, O_RDWR); 286 if (fd < 0) { 287 /* Linux-only, we can use %m in printf. */ 288 error_report("Failed to open %s: %m", device); 289 goto out_socket; 290 } 291 292 ret = nbd_init(fd, sioc, &info, &local_error); 293 if (ret < 0) { 294 error_report_err(local_error); 295 goto out_fd; 296 } 297 298 /* update partition table */ 299 pthread_create(&show_parts_thread, NULL, show_parts, device); 300 301 if (verbose) { 302 fprintf(stderr, "NBD device %s is now connected to %s\n", 303 device, srcpath); 304 } else { 305 /* Close stderr so that the qemu-nbd process exits. */ 306 dup2(STDOUT_FILENO, STDERR_FILENO); 307 } 308 309 ret = nbd_client(fd); 310 if (ret) { 311 goto out_fd; 312 } 313 close(fd); 314 object_unref(OBJECT(sioc)); 315 g_free(info.name); 316 kill(getpid(), SIGTERM); 317 return (void *) EXIT_SUCCESS; 318 319 out_fd: 320 close(fd); 321 out_socket: 322 object_unref(OBJECT(sioc)); 323 out: 324 g_free(info.name); 325 kill(getpid(), SIGTERM); 326 return (void *) EXIT_FAILURE; 327 } 328 #endif /* HAVE_NBD_DEVICE */ 329 330 static int nbd_can_accept(void) 331 { 332 return state == RUNNING && nb_fds < shared; 333 } 334 335 static void nbd_export_closed(NBDExport *export) 336 { 337 assert(state == TERMINATING); 338 state = TERMINATED; 339 } 340 341 static void nbd_update_server_watch(void); 342 343 static void nbd_client_closed(NBDClient *client, bool negotiated) 344 { 345 nb_fds--; 346 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 347 state = TERMINATE; 348 } 349 nbd_update_server_watch(); 350 nbd_client_put(client); 351 } 352 353 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 354 gpointer opaque) 355 { 356 if (state >= TERMINATE) { 357 return; 358 } 359 360 nb_fds++; 361 nbd_update_server_watch(); 362 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 363 } 364 365 static void nbd_update_server_watch(void) 366 { 367 if (nbd_can_accept()) { 368 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 369 } else { 370 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 371 } 372 } 373 374 375 static SocketAddress *nbd_build_socket_address(const char *sockpath, 376 const char *bindto, 377 const char *port) 378 { 379 SocketAddress *saddr; 380 381 saddr = g_new0(SocketAddress, 1); 382 if (sockpath) { 383 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 384 saddr->u.q_unix.path = g_strdup(sockpath); 385 } else { 386 InetSocketAddress *inet; 387 saddr->type = SOCKET_ADDRESS_TYPE_INET; 388 inet = &saddr->u.inet; 389 inet->host = g_strdup(bindto); 390 if (port) { 391 inet->port = g_strdup(port); 392 } else { 393 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 394 } 395 } 396 397 return saddr; 398 } 399 400 401 static QemuOptsList file_opts = { 402 .name = "file", 403 .implied_opt_name = "file", 404 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 405 .desc = { 406 /* no elements => accept any params */ 407 { /* end of list */ } 408 }, 409 }; 410 411 static QemuOptsList qemu_object_opts = { 412 .name = "object", 413 .implied_opt_name = "qom-type", 414 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 415 .desc = { 416 { } 417 }, 418 }; 419 420 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts) 421 { 422 if (user_creatable_print_help(type, opts)) { 423 exit(0); 424 } 425 return true; 426 } 427 428 429 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 430 Error **errp) 431 { 432 Object *obj; 433 QCryptoTLSCreds *creds; 434 435 obj = object_resolve_path_component( 436 object_get_objects_root(), id); 437 if (!obj) { 438 error_setg(errp, "No TLS credentials with id '%s'", 439 id); 440 return NULL; 441 } 442 creds = (QCryptoTLSCreds *) 443 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 444 if (!creds) { 445 error_setg(errp, "Object with id '%s' is not TLS credentials", 446 id); 447 return NULL; 448 } 449 450 if (list) { 451 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 452 error_setg(errp, 453 "Expecting TLS credentials with a client endpoint"); 454 return NULL; 455 } 456 } else { 457 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 458 error_setg(errp, 459 "Expecting TLS credentials with a server endpoint"); 460 return NULL; 461 } 462 } 463 object_ref(obj); 464 return creds; 465 } 466 467 static void setup_address_and_port(const char **address, const char **port) 468 { 469 if (*address == NULL) { 470 *address = "0.0.0.0"; 471 } 472 473 if (*port == NULL) { 474 *port = stringify(NBD_DEFAULT_PORT); 475 } 476 } 477 478 /* 479 * Check socket parameters compatibility when socket activation is used. 480 */ 481 static const char *socket_activation_validate_opts(const char *device, 482 const char *sockpath, 483 const char *address, 484 const char *port, 485 bool list) 486 { 487 if (device != NULL) { 488 return "NBD device can't be set when using socket activation"; 489 } 490 491 if (sockpath != NULL) { 492 return "Unix socket can't be set when using socket activation"; 493 } 494 495 if (address != NULL) { 496 return "The interface can't be set when using socket activation"; 497 } 498 499 if (port != NULL) { 500 return "TCP port number can't be set when using socket activation"; 501 } 502 503 if (list) { 504 return "List mode is incompatible with socket activation"; 505 } 506 507 return NULL; 508 } 509 510 static void qemu_nbd_shutdown(void) 511 { 512 job_cancel_sync_all(); 513 bdrv_close_all(); 514 } 515 516 int main(int argc, char **argv) 517 { 518 BlockBackend *blk; 519 BlockDriverState *bs; 520 uint64_t dev_offset = 0; 521 bool readonly = false; 522 bool disconnect = false; 523 const char *bindto = NULL; 524 const char *port = NULL; 525 char *sockpath = NULL; 526 char *device = NULL; 527 int64_t fd_size; 528 QemuOpts *sn_opts = NULL; 529 const char *sn_id_or_name = NULL; 530 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:B:L"; 531 struct option lopt[] = { 532 { "help", no_argument, NULL, 'h' }, 533 { "version", no_argument, NULL, 'V' }, 534 { "bind", required_argument, NULL, 'b' }, 535 { "port", required_argument, NULL, 'p' }, 536 { "socket", required_argument, NULL, 'k' }, 537 { "offset", required_argument, NULL, 'o' }, 538 { "read-only", no_argument, NULL, 'r' }, 539 { "bitmap", required_argument, NULL, 'B' }, 540 { "connect", required_argument, NULL, 'c' }, 541 { "disconnect", no_argument, NULL, 'd' }, 542 { "list", no_argument, NULL, 'L' }, 543 { "snapshot", no_argument, NULL, 's' }, 544 { "load-snapshot", required_argument, NULL, 'l' }, 545 { "nocache", no_argument, NULL, 'n' }, 546 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 547 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 548 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 549 { "detect-zeroes", required_argument, NULL, 550 QEMU_NBD_OPT_DETECT_ZEROES }, 551 { "shared", required_argument, NULL, 'e' }, 552 { "format", required_argument, NULL, 'f' }, 553 { "persistent", no_argument, NULL, 't' }, 554 { "verbose", no_argument, NULL, 'v' }, 555 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 556 { "export-name", required_argument, NULL, 'x' }, 557 { "description", required_argument, NULL, 'D' }, 558 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 559 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 560 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 561 { "trace", required_argument, NULL, 'T' }, 562 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 563 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 564 { NULL, 0, NULL, 0 } 565 }; 566 int ch; 567 int opt_ind = 0; 568 int flags = BDRV_O_RDWR; 569 int ret = 0; 570 bool seen_cache = false; 571 bool seen_discard = false; 572 bool seen_aio = false; 573 pthread_t client_thread; 574 const char *fmt = NULL; 575 Error *local_err = NULL; 576 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 577 QDict *options = NULL; 578 const char *export_name = NULL; /* defaults to "" later for server mode */ 579 const char *export_description = NULL; 580 const char *bitmap = NULL; 581 const char *tlscredsid = NULL; 582 bool imageOpts = false; 583 bool writethrough = true; 584 char *trace_file = NULL; 585 bool fork_process = false; 586 bool list = false; 587 int old_stderr = -1; 588 unsigned socket_activation; 589 const char *pid_file_name = NULL; 590 591 #if HAVE_NBD_DEVICE 592 /* The client thread uses SIGTERM to interrupt the server. A signal 593 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 594 */ 595 struct sigaction sa_sigterm; 596 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 597 sa_sigterm.sa_handler = termsig_handler; 598 sigaction(SIGTERM, &sa_sigterm, NULL); 599 #endif /* HAVE_NBD_DEVICE */ 600 601 #ifdef CONFIG_POSIX 602 signal(SIGPIPE, SIG_IGN); 603 #endif 604 605 socket_init(); 606 error_init(argv[0]); 607 module_call_init(MODULE_INIT_TRACE); 608 qcrypto_init(&error_fatal); 609 610 module_call_init(MODULE_INIT_QOM); 611 qemu_add_opts(&qemu_object_opts); 612 qemu_add_opts(&qemu_trace_opts); 613 qemu_init_exec_dir(argv[0]); 614 615 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 616 switch (ch) { 617 case 's': 618 flags |= BDRV_O_SNAPSHOT; 619 break; 620 case 'n': 621 optarg = (char *) "none"; 622 /* fallthrough */ 623 case QEMU_NBD_OPT_CACHE: 624 if (seen_cache) { 625 error_report("-n and --cache can only be specified once"); 626 exit(EXIT_FAILURE); 627 } 628 seen_cache = true; 629 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 630 error_report("Invalid cache mode `%s'", optarg); 631 exit(EXIT_FAILURE); 632 } 633 break; 634 case QEMU_NBD_OPT_AIO: 635 if (seen_aio) { 636 error_report("--aio can only be specified once"); 637 exit(EXIT_FAILURE); 638 } 639 seen_aio = true; 640 if (bdrv_parse_aio(optarg, &flags) < 0) { 641 error_report("Invalid aio mode '%s'", optarg); 642 exit(EXIT_FAILURE); 643 } 644 break; 645 case QEMU_NBD_OPT_DISCARD: 646 if (seen_discard) { 647 error_report("--discard can only be specified once"); 648 exit(EXIT_FAILURE); 649 } 650 seen_discard = true; 651 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 652 error_report("Invalid discard mode `%s'", optarg); 653 exit(EXIT_FAILURE); 654 } 655 break; 656 case QEMU_NBD_OPT_DETECT_ZEROES: 657 detect_zeroes = 658 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 659 optarg, 660 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 661 &local_err); 662 if (local_err) { 663 error_reportf_err(local_err, 664 "Failed to parse detect_zeroes mode: "); 665 exit(EXIT_FAILURE); 666 } 667 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 668 !(flags & BDRV_O_UNMAP)) { 669 error_report("setting detect-zeroes to unmap is not allowed " 670 "without setting discard operation to unmap"); 671 exit(EXIT_FAILURE); 672 } 673 break; 674 case 'b': 675 bindto = optarg; 676 break; 677 case 'p': 678 port = optarg; 679 break; 680 case 'o': 681 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 682 error_report("Invalid offset '%s'", optarg); 683 exit(EXIT_FAILURE); 684 } 685 break; 686 case 'l': 687 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 688 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 689 optarg, false); 690 if (!sn_opts) { 691 error_report("Failed in parsing snapshot param `%s'", 692 optarg); 693 exit(EXIT_FAILURE); 694 } 695 } else { 696 sn_id_or_name = optarg; 697 } 698 /* fall through */ 699 case 'r': 700 readonly = true; 701 flags &= ~BDRV_O_RDWR; 702 break; 703 case 'B': 704 bitmap = optarg; 705 break; 706 case 'k': 707 sockpath = optarg; 708 if (sockpath[0] != '/') { 709 error_report("socket path must be absolute"); 710 exit(EXIT_FAILURE); 711 } 712 break; 713 case 'd': 714 disconnect = true; 715 break; 716 case 'c': 717 device = optarg; 718 break; 719 case 'e': 720 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 721 shared < 1) { 722 error_report("Invalid shared device number '%s'", optarg); 723 exit(EXIT_FAILURE); 724 } 725 break; 726 case 'f': 727 fmt = optarg; 728 break; 729 case 't': 730 persistent = 1; 731 break; 732 case 'x': 733 export_name = optarg; 734 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 735 error_report("export name '%s' too long", export_name); 736 exit(EXIT_FAILURE); 737 } 738 break; 739 case 'D': 740 export_description = optarg; 741 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 742 error_report("export description '%s' too long", 743 export_description); 744 exit(EXIT_FAILURE); 745 } 746 break; 747 case 'v': 748 verbose = 1; 749 break; 750 case 'V': 751 version(argv[0]); 752 exit(0); 753 break; 754 case 'h': 755 usage(argv[0]); 756 exit(0); 757 break; 758 case '?': 759 error_report("Try `%s --help' for more information.", argv[0]); 760 exit(EXIT_FAILURE); 761 case QEMU_NBD_OPT_OBJECT: { 762 QemuOpts *opts; 763 opts = qemu_opts_parse_noisily(&qemu_object_opts, 764 optarg, true); 765 if (!opts) { 766 exit(EXIT_FAILURE); 767 } 768 } break; 769 case QEMU_NBD_OPT_TLSCREDS: 770 tlscredsid = optarg; 771 break; 772 case QEMU_NBD_OPT_IMAGE_OPTS: 773 imageOpts = true; 774 break; 775 case 'T': 776 g_free(trace_file); 777 trace_file = trace_opt_parse(optarg); 778 break; 779 case QEMU_NBD_OPT_TLSAUTHZ: 780 tlsauthz = optarg; 781 break; 782 case QEMU_NBD_OPT_FORK: 783 fork_process = true; 784 break; 785 case 'L': 786 list = true; 787 break; 788 case QEMU_NBD_OPT_PID_FILE: 789 pid_file_name = optarg; 790 break; 791 } 792 } 793 794 if (list) { 795 if (argc != optind) { 796 error_report("List mode is incompatible with a file name"); 797 exit(EXIT_FAILURE); 798 } 799 if (export_name || export_description || dev_offset || 800 device || disconnect || fmt || sn_id_or_name || bitmap || 801 seen_aio || seen_discard || seen_cache) { 802 error_report("List mode is incompatible with per-device settings"); 803 exit(EXIT_FAILURE); 804 } 805 if (fork_process) { 806 error_report("List mode is incompatible with forking"); 807 exit(EXIT_FAILURE); 808 } 809 } else if ((argc - optind) != 1) { 810 error_report("Invalid number of arguments"); 811 error_printf("Try `%s --help' for more information.\n", argv[0]); 812 exit(EXIT_FAILURE); 813 } else if (!export_name) { 814 export_name = ""; 815 } 816 817 qemu_opts_foreach(&qemu_object_opts, 818 user_creatable_add_opts_foreach, 819 qemu_nbd_object_print_help, &error_fatal); 820 821 if (!trace_init_backends()) { 822 exit(1); 823 } 824 trace_init_file(trace_file); 825 qemu_set_log(LOG_TRACE); 826 827 socket_activation = check_socket_activation(); 828 if (socket_activation == 0) { 829 setup_address_and_port(&bindto, &port); 830 } else { 831 /* Using socket activation - check user didn't use -p etc. */ 832 const char *err_msg = socket_activation_validate_opts(device, sockpath, 833 bindto, port, 834 list); 835 if (err_msg != NULL) { 836 error_report("%s", err_msg); 837 exit(EXIT_FAILURE); 838 } 839 840 /* qemu-nbd can only listen on a single socket. */ 841 if (socket_activation > 1) { 842 error_report("qemu-nbd does not support socket activation with %s > 1", 843 "LISTEN_FDS"); 844 exit(EXIT_FAILURE); 845 } 846 } 847 848 if (tlscredsid) { 849 if (sockpath) { 850 error_report("TLS is only supported with IPv4/IPv6"); 851 exit(EXIT_FAILURE); 852 } 853 if (device) { 854 error_report("TLS is not supported with a host device"); 855 exit(EXIT_FAILURE); 856 } 857 if (tlsauthz && list) { 858 error_report("TLS authorization is incompatible with export list"); 859 exit(EXIT_FAILURE); 860 } 861 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 862 if (local_err) { 863 error_reportf_err(local_err, "Failed to get TLS creds: "); 864 exit(EXIT_FAILURE); 865 } 866 } else { 867 if (tlsauthz) { 868 error_report("--tls-authz is not permitted without --tls-creds"); 869 exit(EXIT_FAILURE); 870 } 871 } 872 873 if (list) { 874 saddr = nbd_build_socket_address(sockpath, bindto, port); 875 return qemu_nbd_client_list(saddr, tlscreds, bindto); 876 } 877 878 #if !HAVE_NBD_DEVICE 879 if (disconnect || device) { 880 error_report("Kernel /dev/nbdN support not available"); 881 exit(EXIT_FAILURE); 882 } 883 #else /* HAVE_NBD_DEVICE */ 884 if (disconnect) { 885 int nbdfd = open(argv[optind], O_RDWR); 886 if (nbdfd < 0) { 887 error_report("Cannot open %s: %s", argv[optind], 888 strerror(errno)); 889 exit(EXIT_FAILURE); 890 } 891 nbd_disconnect(nbdfd); 892 893 close(nbdfd); 894 895 printf("%s disconnected\n", argv[optind]); 896 897 return 0; 898 } 899 #endif 900 901 if ((device && !verbose) || fork_process) { 902 #ifndef WIN32 903 int stderr_fd[2]; 904 pid_t pid; 905 int ret; 906 907 if (qemu_pipe(stderr_fd) < 0) { 908 error_report("Error setting up communication pipe: %s", 909 strerror(errno)); 910 exit(EXIT_FAILURE); 911 } 912 913 /* Now daemonize, but keep a communication channel open to 914 * print errors and exit with the proper status code. 915 */ 916 pid = fork(); 917 if (pid < 0) { 918 error_report("Failed to fork: %s", strerror(errno)); 919 exit(EXIT_FAILURE); 920 } else if (pid == 0) { 921 close(stderr_fd[0]); 922 923 /* Remember parent's stderr if we will be restoring it. */ 924 if (fork_process) { 925 old_stderr = dup(STDERR_FILENO); 926 } 927 928 ret = qemu_daemon(1, 0); 929 930 /* Temporarily redirect stderr to the parent's pipe... */ 931 dup2(stderr_fd[1], STDERR_FILENO); 932 if (ret < 0) { 933 error_report("Failed to daemonize: %s", strerror(errno)); 934 exit(EXIT_FAILURE); 935 } 936 937 /* ... close the descriptor we inherited and go on. */ 938 close(stderr_fd[1]); 939 } else { 940 bool errors = false; 941 char *buf; 942 943 /* In the parent. Print error messages from the child until 944 * it closes the pipe. 945 */ 946 close(stderr_fd[1]); 947 buf = g_malloc(1024); 948 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 949 errors = true; 950 ret = qemu_write_full(STDERR_FILENO, buf, ret); 951 if (ret < 0) { 952 exit(EXIT_FAILURE); 953 } 954 } 955 if (ret < 0) { 956 error_report("Cannot read from daemon: %s", 957 strerror(errno)); 958 exit(EXIT_FAILURE); 959 } 960 961 /* Usually the daemon should not print any message. 962 * Exit with zero status in that case. 963 */ 964 exit(errors); 965 } 966 #else /* WIN32 */ 967 error_report("Unable to fork into background on Windows hosts"); 968 exit(EXIT_FAILURE); 969 #endif /* WIN32 */ 970 } 971 972 if (device != NULL && sockpath == NULL) { 973 sockpath = g_malloc(128); 974 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 975 } 976 977 server = qio_net_listener_new(); 978 if (socket_activation == 0) { 979 saddr = nbd_build_socket_address(sockpath, bindto, port); 980 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) { 981 object_unref(OBJECT(server)); 982 error_report_err(local_err); 983 exit(EXIT_FAILURE); 984 } 985 } else { 986 size_t i; 987 /* See comment in check_socket_activation above. */ 988 for (i = 0; i < socket_activation; i++) { 989 QIOChannelSocket *sioc; 990 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 991 &local_err); 992 if (sioc == NULL) { 993 object_unref(OBJECT(server)); 994 error_reportf_err(local_err, 995 "Failed to use socket activation: "); 996 exit(EXIT_FAILURE); 997 } 998 qio_net_listener_add(server, sioc); 999 object_unref(OBJECT(sioc)); 1000 } 1001 } 1002 1003 if (qemu_init_main_loop(&local_err)) { 1004 error_report_err(local_err); 1005 exit(EXIT_FAILURE); 1006 } 1007 bdrv_init(); 1008 atexit(qemu_nbd_shutdown); 1009 1010 srcpath = argv[optind]; 1011 if (imageOpts) { 1012 QemuOpts *opts; 1013 if (fmt) { 1014 error_report("--image-opts and -f are mutually exclusive"); 1015 exit(EXIT_FAILURE); 1016 } 1017 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1018 if (!opts) { 1019 qemu_opts_reset(&file_opts); 1020 exit(EXIT_FAILURE); 1021 } 1022 options = qemu_opts_to_qdict(opts, NULL); 1023 qemu_opts_reset(&file_opts); 1024 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1025 } else { 1026 if (fmt) { 1027 options = qdict_new(); 1028 qdict_put_str(options, "driver", fmt); 1029 } 1030 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1031 } 1032 1033 if (!blk) { 1034 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1035 argv[optind]); 1036 exit(EXIT_FAILURE); 1037 } 1038 bs = blk_bs(blk); 1039 1040 blk_set_enable_write_cache(blk, !writethrough); 1041 1042 if (sn_opts) { 1043 ret = bdrv_snapshot_load_tmp(bs, 1044 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1045 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1046 &local_err); 1047 } else if (sn_id_or_name) { 1048 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1049 &local_err); 1050 } 1051 if (ret < 0) { 1052 error_reportf_err(local_err, "Failed to load snapshot: "); 1053 exit(EXIT_FAILURE); 1054 } 1055 1056 bs->detect_zeroes = detect_zeroes; 1057 fd_size = blk_getlength(blk); 1058 if (fd_size < 0) { 1059 error_report("Failed to determine the image length: %s", 1060 strerror(-fd_size)); 1061 exit(EXIT_FAILURE); 1062 } 1063 1064 if (dev_offset >= fd_size) { 1065 error_report("Offset (%" PRIu64 ") has to be smaller than the image " 1066 "size (%" PRId64 ")", dev_offset, fd_size); 1067 exit(EXIT_FAILURE); 1068 } 1069 fd_size -= dev_offset; 1070 1071 export = nbd_export_new(bs, dev_offset, fd_size, export_name, 1072 export_description, bitmap, readonly, shared > 1, 1073 nbd_export_closed, writethrough, NULL, 1074 &error_fatal); 1075 1076 if (device) { 1077 #if HAVE_NBD_DEVICE 1078 int ret; 1079 1080 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1081 if (ret != 0) { 1082 error_report("Failed to create client thread: %s", strerror(ret)); 1083 exit(EXIT_FAILURE); 1084 } 1085 #endif 1086 } else { 1087 /* Shut up GCC warnings. */ 1088 memset(&client_thread, 0, sizeof(client_thread)); 1089 } 1090 1091 nbd_update_server_watch(); 1092 1093 if (pid_file_name) { 1094 qemu_write_pidfile(pid_file_name, &error_fatal); 1095 } 1096 1097 /* now when the initialization is (almost) complete, chdir("/") 1098 * to free any busy filesystems */ 1099 if (chdir("/") < 0) { 1100 error_report("Could not chdir to root directory: %s", 1101 strerror(errno)); 1102 exit(EXIT_FAILURE); 1103 } 1104 1105 if (fork_process) { 1106 dup2(old_stderr, STDERR_FILENO); 1107 close(old_stderr); 1108 } 1109 1110 state = RUNNING; 1111 do { 1112 main_loop_wait(false); 1113 if (state == TERMINATE) { 1114 state = TERMINATING; 1115 nbd_export_close(export); 1116 nbd_export_put(export); 1117 export = NULL; 1118 } 1119 } while (state != TERMINATED); 1120 1121 blk_unref(blk); 1122 if (sockpath) { 1123 unlink(sockpath); 1124 } 1125 1126 qemu_opts_del(sn_opts); 1127 1128 if (device) { 1129 void *ret; 1130 pthread_join(client_thread, &ret); 1131 exit(ret != NULL); 1132 } else { 1133 exit(EXIT_SUCCESS); 1134 } 1135 } 1136