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 "sysemu/runstate.h" /* for qemu_system_killed() prototype */ 29 #include "block/block_int.h" 30 #include "block/nbd.h" 31 #include "qemu/main-loop.h" 32 #include "qemu/module.h" 33 #include "qemu/option.h" 34 #include "qemu/error-report.h" 35 #include "qemu/config-file.h" 36 #include "qemu/bswap.h" 37 #include "qemu/log.h" 38 #include "qemu/systemd.h" 39 #include "block/snapshot.h" 40 #include "qapi/qmp/qdict.h" 41 #include "qapi/qmp/qstring.h" 42 #include "qom/object_interfaces.h" 43 #include "io/channel-socket.h" 44 #include "io/net-listener.h" 45 #include "crypto/init.h" 46 #include "trace/control.h" 47 #include "qemu-version.h" 48 49 #ifdef __linux__ 50 #define HAVE_NBD_DEVICE 1 51 #else 52 #define HAVE_NBD_DEVICE 0 53 #endif 54 55 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 56 #define QEMU_NBD_OPT_CACHE 256 57 #define QEMU_NBD_OPT_AIO 257 58 #define QEMU_NBD_OPT_DISCARD 258 59 #define QEMU_NBD_OPT_DETECT_ZEROES 259 60 #define QEMU_NBD_OPT_OBJECT 260 61 #define QEMU_NBD_OPT_TLSCREDS 261 62 #define QEMU_NBD_OPT_IMAGE_OPTS 262 63 #define QEMU_NBD_OPT_FORK 263 64 #define QEMU_NBD_OPT_TLSAUTHZ 264 65 #define QEMU_NBD_OPT_PID_FILE 265 66 67 #define MBR_SIZE 512 68 69 static int verbose; 70 static char *srcpath; 71 static SocketAddress *saddr; 72 static int persistent = 0; 73 static enum { RUNNING, TERMINATE, 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 #ifdef CONFIG_POSIX 159 /* 160 * The client thread uses SIGTERM to interrupt the server. A signal 161 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 162 */ 163 void qemu_system_killed(int signum, pid_t pid) 164 { 165 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 166 qemu_notify_event(); 167 } 168 #endif /* CONFIG_POSIX */ 169 170 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 171 const char *hostname) 172 { 173 int ret = EXIT_FAILURE; 174 int rc; 175 Error *err = NULL; 176 QIOChannelSocket *sioc; 177 NBDExportInfo *list; 178 int i, j; 179 180 sioc = qio_channel_socket_new(); 181 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 182 error_report_err(err); 183 return EXIT_FAILURE; 184 } 185 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 186 &err); 187 if (rc < 0) { 188 if (err) { 189 error_report_err(err); 190 } 191 goto out; 192 } 193 printf("exports available: %d\n", rc); 194 for (i = 0; i < rc; i++) { 195 printf(" export: '%s'\n", list[i].name); 196 if (list[i].description && *list[i].description) { 197 printf(" description: %s\n", list[i].description); 198 } 199 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 200 static const char *const flag_names[] = { 201 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 202 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 203 [NBD_FLAG_SEND_FUA_BIT] = "fua", 204 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 205 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 206 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 207 [NBD_FLAG_SEND_DF_BIT] = "df", 208 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 209 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 210 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 211 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 212 }; 213 214 printf(" size: %" PRIu64 "\n", list[i].size); 215 printf(" flags: 0x%x (", list[i].flags); 216 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 217 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 218 printf(" %s", flag_names[bit]); 219 } 220 } 221 printf(" )\n"); 222 } 223 if (list[i].min_block) { 224 printf(" min block: %u\n", list[i].min_block); 225 printf(" opt block: %u\n", list[i].opt_block); 226 printf(" max block: %u\n", list[i].max_block); 227 } 228 if (list[i].n_contexts) { 229 printf(" available meta contexts: %d\n", list[i].n_contexts); 230 for (j = 0; j < list[i].n_contexts; j++) { 231 printf(" %s\n", list[i].contexts[j]); 232 } 233 } 234 } 235 nbd_free_export_list(list, rc); 236 237 ret = EXIT_SUCCESS; 238 out: 239 object_unref(OBJECT(sioc)); 240 return ret; 241 } 242 243 244 #if HAVE_NBD_DEVICE 245 static void *show_parts(void *arg) 246 { 247 char *device = arg; 248 int nbd; 249 250 /* linux just needs an open() to trigger 251 * the partition table update 252 * but remember to load the module with max_part != 0 : 253 * modprobe nbd max_part=63 254 */ 255 nbd = open(device, O_RDWR); 256 if (nbd >= 0) { 257 close(nbd); 258 } 259 return NULL; 260 } 261 262 static void *nbd_client_thread(void *arg) 263 { 264 char *device = arg; 265 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 266 QIOChannelSocket *sioc; 267 int fd; 268 int ret; 269 pthread_t show_parts_thread; 270 Error *local_error = NULL; 271 272 sioc = qio_channel_socket_new(); 273 if (qio_channel_socket_connect_sync(sioc, 274 saddr, 275 &local_error) < 0) { 276 error_report_err(local_error); 277 goto out; 278 } 279 280 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 281 NULL, NULL, NULL, &info, &local_error); 282 if (ret < 0) { 283 if (local_error) { 284 error_report_err(local_error); 285 } 286 goto out_socket; 287 } 288 289 fd = open(device, O_RDWR); 290 if (fd < 0) { 291 /* Linux-only, we can use %m in printf. */ 292 error_report("Failed to open %s: %m", device); 293 goto out_socket; 294 } 295 296 ret = nbd_init(fd, sioc, &info, &local_error); 297 if (ret < 0) { 298 error_report_err(local_error); 299 goto out_fd; 300 } 301 302 /* update partition table */ 303 pthread_create(&show_parts_thread, NULL, show_parts, device); 304 305 if (verbose) { 306 fprintf(stderr, "NBD device %s is now connected to %s\n", 307 device, srcpath); 308 } else { 309 /* Close stderr so that the qemu-nbd process exits. */ 310 dup2(STDOUT_FILENO, STDERR_FILENO); 311 } 312 313 ret = nbd_client(fd); 314 if (ret) { 315 goto out_fd; 316 } 317 close(fd); 318 object_unref(OBJECT(sioc)); 319 g_free(info.name); 320 kill(getpid(), SIGTERM); 321 return (void *) EXIT_SUCCESS; 322 323 out_fd: 324 close(fd); 325 out_socket: 326 object_unref(OBJECT(sioc)); 327 out: 328 g_free(info.name); 329 kill(getpid(), SIGTERM); 330 return (void *) EXIT_FAILURE; 331 } 332 #endif /* HAVE_NBD_DEVICE */ 333 334 static int nbd_can_accept(void) 335 { 336 return state == RUNNING && nb_fds < shared; 337 } 338 339 static void nbd_update_server_watch(void); 340 341 static void nbd_client_closed(NBDClient *client, bool negotiated) 342 { 343 nb_fds--; 344 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 345 state = TERMINATE; 346 } 347 nbd_update_server_watch(); 348 nbd_client_put(client); 349 } 350 351 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 352 gpointer opaque) 353 { 354 if (state >= TERMINATE) { 355 return; 356 } 357 358 nb_fds++; 359 nbd_update_server_watch(); 360 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 361 } 362 363 static void nbd_update_server_watch(void) 364 { 365 if (nbd_can_accept()) { 366 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 367 } else { 368 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 369 } 370 } 371 372 373 static SocketAddress *nbd_build_socket_address(const char *sockpath, 374 const char *bindto, 375 const char *port) 376 { 377 SocketAddress *saddr; 378 379 saddr = g_new0(SocketAddress, 1); 380 if (sockpath) { 381 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 382 saddr->u.q_unix.path = g_strdup(sockpath); 383 } else { 384 InetSocketAddress *inet; 385 saddr->type = SOCKET_ADDRESS_TYPE_INET; 386 inet = &saddr->u.inet; 387 inet->host = g_strdup(bindto); 388 if (port) { 389 inet->port = g_strdup(port); 390 } else { 391 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 392 } 393 } 394 395 return saddr; 396 } 397 398 399 static QemuOptsList file_opts = { 400 .name = "file", 401 .implied_opt_name = "file", 402 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 403 .desc = { 404 /* no elements => accept any params */ 405 { /* end of list */ } 406 }, 407 }; 408 409 static QemuOptsList qemu_object_opts = { 410 .name = "object", 411 .implied_opt_name = "qom-type", 412 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 413 .desc = { 414 { } 415 }, 416 }; 417 418 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts) 419 { 420 if (user_creatable_print_help(type, opts)) { 421 exit(0); 422 } 423 return true; 424 } 425 426 427 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 428 Error **errp) 429 { 430 Object *obj; 431 QCryptoTLSCreds *creds; 432 433 obj = object_resolve_path_component( 434 object_get_objects_root(), id); 435 if (!obj) { 436 error_setg(errp, "No TLS credentials with id '%s'", 437 id); 438 return NULL; 439 } 440 creds = (QCryptoTLSCreds *) 441 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 442 if (!creds) { 443 error_setg(errp, "Object with id '%s' is not TLS credentials", 444 id); 445 return NULL; 446 } 447 448 if (list) { 449 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 450 error_setg(errp, 451 "Expecting TLS credentials with a client endpoint"); 452 return NULL; 453 } 454 } else { 455 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 456 error_setg(errp, 457 "Expecting TLS credentials with a server endpoint"); 458 return NULL; 459 } 460 } 461 object_ref(obj); 462 return creds; 463 } 464 465 static void setup_address_and_port(const char **address, const char **port) 466 { 467 if (*address == NULL) { 468 *address = "0.0.0.0"; 469 } 470 471 if (*port == NULL) { 472 *port = stringify(NBD_DEFAULT_PORT); 473 } 474 } 475 476 /* 477 * Check socket parameters compatibility when socket activation is used. 478 */ 479 static const char *socket_activation_validate_opts(const char *device, 480 const char *sockpath, 481 const char *address, 482 const char *port, 483 bool list) 484 { 485 if (device != NULL) { 486 return "NBD device can't be set when using socket activation"; 487 } 488 489 if (sockpath != NULL) { 490 return "Unix socket can't be set when using socket activation"; 491 } 492 493 if (address != NULL) { 494 return "The interface can't be set when using socket activation"; 495 } 496 497 if (port != NULL) { 498 return "TCP port number can't be set when using socket activation"; 499 } 500 501 if (list) { 502 return "List mode is incompatible with socket activation"; 503 } 504 505 return NULL; 506 } 507 508 static void qemu_nbd_shutdown(void) 509 { 510 job_cancel_sync_all(); 511 bdrv_close_all(); 512 } 513 514 int main(int argc, char **argv) 515 { 516 BlockBackend *blk; 517 BlockDriverState *bs; 518 uint64_t dev_offset = 0; 519 bool readonly = false; 520 bool disconnect = false; 521 const char *bindto = NULL; 522 const char *port = NULL; 523 char *sockpath = NULL; 524 char *device = NULL; 525 QemuOpts *sn_opts = NULL; 526 const char *sn_id_or_name = NULL; 527 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:B:L"; 528 struct option lopt[] = { 529 { "help", no_argument, NULL, 'h' }, 530 { "version", no_argument, NULL, 'V' }, 531 { "bind", required_argument, NULL, 'b' }, 532 { "port", required_argument, NULL, 'p' }, 533 { "socket", required_argument, NULL, 'k' }, 534 { "offset", required_argument, NULL, 'o' }, 535 { "read-only", no_argument, NULL, 'r' }, 536 { "bitmap", required_argument, NULL, 'B' }, 537 { "connect", required_argument, NULL, 'c' }, 538 { "disconnect", no_argument, NULL, 'd' }, 539 { "list", no_argument, NULL, 'L' }, 540 { "snapshot", no_argument, NULL, 's' }, 541 { "load-snapshot", required_argument, NULL, 'l' }, 542 { "nocache", no_argument, NULL, 'n' }, 543 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 544 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 545 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 546 { "detect-zeroes", required_argument, NULL, 547 QEMU_NBD_OPT_DETECT_ZEROES }, 548 { "shared", required_argument, NULL, 'e' }, 549 { "format", required_argument, NULL, 'f' }, 550 { "persistent", no_argument, NULL, 't' }, 551 { "verbose", no_argument, NULL, 'v' }, 552 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 553 { "export-name", required_argument, NULL, 'x' }, 554 { "description", required_argument, NULL, 'D' }, 555 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 556 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 557 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 558 { "trace", required_argument, NULL, 'T' }, 559 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 560 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 561 { NULL, 0, NULL, 0 } 562 }; 563 int ch; 564 int opt_ind = 0; 565 int flags = BDRV_O_RDWR; 566 int ret = 0; 567 bool seen_cache = false; 568 bool seen_discard = false; 569 bool seen_aio = false; 570 pthread_t client_thread; 571 const char *fmt = NULL; 572 Error *local_err = NULL; 573 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 574 QDict *options = NULL; 575 const char *export_name = NULL; /* defaults to "" later for server mode */ 576 const char *export_description = NULL; 577 const char *bitmap = NULL; 578 const char *tlscredsid = NULL; 579 bool imageOpts = false; 580 bool writethrough = true; 581 char *trace_file = NULL; 582 bool fork_process = false; 583 bool list = false; 584 int old_stderr = -1; 585 unsigned socket_activation; 586 const char *pid_file_name = NULL; 587 BlockExportOptions *export_opts; 588 589 #ifdef CONFIG_POSIX 590 os_setup_early_signal_handling(); 591 os_setup_signal_handling(); 592 #endif 593 594 socket_init(); 595 error_init(argv[0]); 596 module_call_init(MODULE_INIT_TRACE); 597 qcrypto_init(&error_fatal); 598 599 module_call_init(MODULE_INIT_QOM); 600 qemu_add_opts(&qemu_object_opts); 601 qemu_add_opts(&qemu_trace_opts); 602 qemu_init_exec_dir(argv[0]); 603 604 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 605 switch (ch) { 606 case 's': 607 flags |= BDRV_O_SNAPSHOT; 608 break; 609 case 'n': 610 optarg = (char *) "none"; 611 /* fallthrough */ 612 case QEMU_NBD_OPT_CACHE: 613 if (seen_cache) { 614 error_report("-n and --cache can only be specified once"); 615 exit(EXIT_FAILURE); 616 } 617 seen_cache = true; 618 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 619 error_report("Invalid cache mode `%s'", optarg); 620 exit(EXIT_FAILURE); 621 } 622 break; 623 case QEMU_NBD_OPT_AIO: 624 if (seen_aio) { 625 error_report("--aio can only be specified once"); 626 exit(EXIT_FAILURE); 627 } 628 seen_aio = true; 629 if (bdrv_parse_aio(optarg, &flags) < 0) { 630 error_report("Invalid aio mode '%s'", optarg); 631 exit(EXIT_FAILURE); 632 } 633 break; 634 case QEMU_NBD_OPT_DISCARD: 635 if (seen_discard) { 636 error_report("--discard can only be specified once"); 637 exit(EXIT_FAILURE); 638 } 639 seen_discard = true; 640 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 641 error_report("Invalid discard mode `%s'", optarg); 642 exit(EXIT_FAILURE); 643 } 644 break; 645 case QEMU_NBD_OPT_DETECT_ZEROES: 646 detect_zeroes = 647 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 648 optarg, 649 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 650 &local_err); 651 if (local_err) { 652 error_reportf_err(local_err, 653 "Failed to parse detect_zeroes mode: "); 654 exit(EXIT_FAILURE); 655 } 656 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 657 !(flags & BDRV_O_UNMAP)) { 658 error_report("setting detect-zeroes to unmap is not allowed " 659 "without setting discard operation to unmap"); 660 exit(EXIT_FAILURE); 661 } 662 break; 663 case 'b': 664 bindto = optarg; 665 break; 666 case 'p': 667 port = optarg; 668 break; 669 case 'o': 670 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 671 error_report("Invalid offset '%s'", optarg); 672 exit(EXIT_FAILURE); 673 } 674 break; 675 case 'l': 676 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 677 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 678 optarg, false); 679 if (!sn_opts) { 680 error_report("Failed in parsing snapshot param `%s'", 681 optarg); 682 exit(EXIT_FAILURE); 683 } 684 } else { 685 sn_id_or_name = optarg; 686 } 687 /* fall through */ 688 case 'r': 689 readonly = true; 690 flags &= ~BDRV_O_RDWR; 691 break; 692 case 'B': 693 bitmap = optarg; 694 break; 695 case 'k': 696 sockpath = optarg; 697 if (sockpath[0] != '/') { 698 error_report("socket path must be absolute"); 699 exit(EXIT_FAILURE); 700 } 701 break; 702 case 'd': 703 disconnect = true; 704 break; 705 case 'c': 706 device = optarg; 707 break; 708 case 'e': 709 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 710 shared < 1) { 711 error_report("Invalid shared device number '%s'", optarg); 712 exit(EXIT_FAILURE); 713 } 714 break; 715 case 'f': 716 fmt = optarg; 717 break; 718 case 't': 719 persistent = 1; 720 break; 721 case 'x': 722 export_name = optarg; 723 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 724 error_report("export name '%s' too long", export_name); 725 exit(EXIT_FAILURE); 726 } 727 break; 728 case 'D': 729 export_description = optarg; 730 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 731 error_report("export description '%s' too long", 732 export_description); 733 exit(EXIT_FAILURE); 734 } 735 break; 736 case 'v': 737 verbose = 1; 738 break; 739 case 'V': 740 version(argv[0]); 741 exit(0); 742 break; 743 case 'h': 744 usage(argv[0]); 745 exit(0); 746 break; 747 case '?': 748 error_report("Try `%s --help' for more information.", argv[0]); 749 exit(EXIT_FAILURE); 750 case QEMU_NBD_OPT_OBJECT: { 751 QemuOpts *opts; 752 opts = qemu_opts_parse_noisily(&qemu_object_opts, 753 optarg, true); 754 if (!opts) { 755 exit(EXIT_FAILURE); 756 } 757 } break; 758 case QEMU_NBD_OPT_TLSCREDS: 759 tlscredsid = optarg; 760 break; 761 case QEMU_NBD_OPT_IMAGE_OPTS: 762 imageOpts = true; 763 break; 764 case 'T': 765 g_free(trace_file); 766 trace_file = trace_opt_parse(optarg); 767 break; 768 case QEMU_NBD_OPT_TLSAUTHZ: 769 tlsauthz = optarg; 770 break; 771 case QEMU_NBD_OPT_FORK: 772 fork_process = true; 773 break; 774 case 'L': 775 list = true; 776 break; 777 case QEMU_NBD_OPT_PID_FILE: 778 pid_file_name = optarg; 779 break; 780 } 781 } 782 783 if (list) { 784 if (argc != optind) { 785 error_report("List mode is incompatible with a file name"); 786 exit(EXIT_FAILURE); 787 } 788 if (export_name || export_description || dev_offset || 789 device || disconnect || fmt || sn_id_or_name || bitmap || 790 seen_aio || seen_discard || seen_cache) { 791 error_report("List mode is incompatible with per-device settings"); 792 exit(EXIT_FAILURE); 793 } 794 if (fork_process) { 795 error_report("List mode is incompatible with forking"); 796 exit(EXIT_FAILURE); 797 } 798 } else if ((argc - optind) != 1) { 799 error_report("Invalid number of arguments"); 800 error_printf("Try `%s --help' for more information.\n", argv[0]); 801 exit(EXIT_FAILURE); 802 } else if (!export_name) { 803 export_name = ""; 804 } 805 806 qemu_opts_foreach(&qemu_object_opts, 807 user_creatable_add_opts_foreach, 808 qemu_nbd_object_print_help, &error_fatal); 809 810 if (!trace_init_backends()) { 811 exit(1); 812 } 813 trace_init_file(trace_file); 814 qemu_set_log(LOG_TRACE); 815 816 socket_activation = check_socket_activation(); 817 if (socket_activation == 0) { 818 setup_address_and_port(&bindto, &port); 819 } else { 820 /* Using socket activation - check user didn't use -p etc. */ 821 const char *err_msg = socket_activation_validate_opts(device, sockpath, 822 bindto, port, 823 list); 824 if (err_msg != NULL) { 825 error_report("%s", err_msg); 826 exit(EXIT_FAILURE); 827 } 828 829 /* qemu-nbd can only listen on a single socket. */ 830 if (socket_activation > 1) { 831 error_report("qemu-nbd does not support socket activation with %s > 1", 832 "LISTEN_FDS"); 833 exit(EXIT_FAILURE); 834 } 835 } 836 837 if (tlscredsid) { 838 if (sockpath) { 839 error_report("TLS is only supported with IPv4/IPv6"); 840 exit(EXIT_FAILURE); 841 } 842 if (device) { 843 error_report("TLS is not supported with a host device"); 844 exit(EXIT_FAILURE); 845 } 846 if (tlsauthz && list) { 847 error_report("TLS authorization is incompatible with export list"); 848 exit(EXIT_FAILURE); 849 } 850 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 851 if (local_err) { 852 error_reportf_err(local_err, "Failed to get TLS creds: "); 853 exit(EXIT_FAILURE); 854 } 855 } else { 856 if (tlsauthz) { 857 error_report("--tls-authz is not permitted without --tls-creds"); 858 exit(EXIT_FAILURE); 859 } 860 } 861 862 if (list) { 863 saddr = nbd_build_socket_address(sockpath, bindto, port); 864 return qemu_nbd_client_list(saddr, tlscreds, bindto); 865 } 866 867 #if !HAVE_NBD_DEVICE 868 if (disconnect || device) { 869 error_report("Kernel /dev/nbdN support not available"); 870 exit(EXIT_FAILURE); 871 } 872 #else /* HAVE_NBD_DEVICE */ 873 if (disconnect) { 874 int nbdfd = open(argv[optind], O_RDWR); 875 if (nbdfd < 0) { 876 error_report("Cannot open %s: %s", argv[optind], 877 strerror(errno)); 878 exit(EXIT_FAILURE); 879 } 880 nbd_disconnect(nbdfd); 881 882 close(nbdfd); 883 884 printf("%s disconnected\n", argv[optind]); 885 886 return 0; 887 } 888 #endif 889 890 if ((device && !verbose) || fork_process) { 891 #ifndef WIN32 892 int stderr_fd[2]; 893 pid_t pid; 894 int ret; 895 896 if (qemu_pipe(stderr_fd) < 0) { 897 error_report("Error setting up communication pipe: %s", 898 strerror(errno)); 899 exit(EXIT_FAILURE); 900 } 901 902 /* Now daemonize, but keep a communication channel open to 903 * print errors and exit with the proper status code. 904 */ 905 pid = fork(); 906 if (pid < 0) { 907 error_report("Failed to fork: %s", strerror(errno)); 908 exit(EXIT_FAILURE); 909 } else if (pid == 0) { 910 close(stderr_fd[0]); 911 912 /* Remember parent's stderr if we will be restoring it. */ 913 if (fork_process) { 914 old_stderr = dup(STDERR_FILENO); 915 } 916 917 ret = qemu_daemon(1, 0); 918 919 /* Temporarily redirect stderr to the parent's pipe... */ 920 dup2(stderr_fd[1], STDERR_FILENO); 921 if (ret < 0) { 922 error_report("Failed to daemonize: %s", strerror(errno)); 923 exit(EXIT_FAILURE); 924 } 925 926 /* ... close the descriptor we inherited and go on. */ 927 close(stderr_fd[1]); 928 } else { 929 bool errors = false; 930 char *buf; 931 932 /* In the parent. Print error messages from the child until 933 * it closes the pipe. 934 */ 935 close(stderr_fd[1]); 936 buf = g_malloc(1024); 937 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 938 errors = true; 939 ret = qemu_write_full(STDERR_FILENO, buf, ret); 940 if (ret < 0) { 941 exit(EXIT_FAILURE); 942 } 943 } 944 if (ret < 0) { 945 error_report("Cannot read from daemon: %s", 946 strerror(errno)); 947 exit(EXIT_FAILURE); 948 } 949 950 /* Usually the daemon should not print any message. 951 * Exit with zero status in that case. 952 */ 953 exit(errors); 954 } 955 #else /* WIN32 */ 956 error_report("Unable to fork into background on Windows hosts"); 957 exit(EXIT_FAILURE); 958 #endif /* WIN32 */ 959 } 960 961 if (device != NULL && sockpath == NULL) { 962 sockpath = g_malloc(128); 963 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 964 } 965 966 server = qio_net_listener_new(); 967 if (socket_activation == 0) { 968 saddr = nbd_build_socket_address(sockpath, bindto, port); 969 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) { 970 object_unref(OBJECT(server)); 971 error_report_err(local_err); 972 exit(EXIT_FAILURE); 973 } 974 } else { 975 size_t i; 976 /* See comment in check_socket_activation above. */ 977 for (i = 0; i < socket_activation; i++) { 978 QIOChannelSocket *sioc; 979 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 980 &local_err); 981 if (sioc == NULL) { 982 object_unref(OBJECT(server)); 983 error_reportf_err(local_err, 984 "Failed to use socket activation: "); 985 exit(EXIT_FAILURE); 986 } 987 qio_net_listener_add(server, sioc); 988 object_unref(OBJECT(sioc)); 989 } 990 } 991 992 if (qemu_init_main_loop(&local_err)) { 993 error_report_err(local_err); 994 exit(EXIT_FAILURE); 995 } 996 bdrv_init(); 997 atexit(qemu_nbd_shutdown); 998 999 srcpath = argv[optind]; 1000 if (imageOpts) { 1001 QemuOpts *opts; 1002 if (fmt) { 1003 error_report("--image-opts and -f are mutually exclusive"); 1004 exit(EXIT_FAILURE); 1005 } 1006 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1007 if (!opts) { 1008 qemu_opts_reset(&file_opts); 1009 exit(EXIT_FAILURE); 1010 } 1011 options = qemu_opts_to_qdict(opts, NULL); 1012 qemu_opts_reset(&file_opts); 1013 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1014 } else { 1015 if (fmt) { 1016 options = qdict_new(); 1017 qdict_put_str(options, "driver", fmt); 1018 } 1019 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1020 } 1021 1022 if (!blk) { 1023 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1024 argv[optind]); 1025 exit(EXIT_FAILURE); 1026 } 1027 bs = blk_bs(blk); 1028 1029 if (dev_offset) { 1030 QDict *raw_opts = qdict_new(); 1031 qdict_put_str(raw_opts, "driver", "raw"); 1032 qdict_put_str(raw_opts, "file", bs->node_name); 1033 qdict_put_int(raw_opts, "offset", dev_offset); 1034 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1035 blk_remove_bs(blk); 1036 blk_insert_bs(blk, bs, &error_fatal); 1037 bdrv_unref(bs); 1038 } 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 1058 nbd_server_is_qemu_nbd(true); 1059 1060 export_opts = g_new(BlockExportOptions, 1); 1061 *export_opts = (BlockExportOptions) { 1062 .type = BLOCK_EXPORT_TYPE_NBD, 1063 .id = g_strdup("qemu-nbd-export"), 1064 .node_name = g_strdup(bdrv_get_node_name(bs)), 1065 .has_writethrough = true, 1066 .writethrough = writethrough, 1067 .has_writable = true, 1068 .writable = !readonly, 1069 .u.nbd = { 1070 .has_name = true, 1071 .name = g_strdup(export_name), 1072 .has_description = !!export_description, 1073 .description = g_strdup(export_description), 1074 .has_bitmap = !!bitmap, 1075 .bitmap = g_strdup(bitmap), 1076 }, 1077 }; 1078 blk_exp_add(export_opts, &error_fatal); 1079 qapi_free_BlockExportOptions(export_opts); 1080 1081 if (device) { 1082 #if HAVE_NBD_DEVICE 1083 int ret; 1084 1085 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1086 if (ret != 0) { 1087 error_report("Failed to create client thread: %s", strerror(ret)); 1088 exit(EXIT_FAILURE); 1089 } 1090 #endif 1091 } else { 1092 /* Shut up GCC warnings. */ 1093 memset(&client_thread, 0, sizeof(client_thread)); 1094 } 1095 1096 nbd_update_server_watch(); 1097 1098 if (pid_file_name) { 1099 qemu_write_pidfile(pid_file_name, &error_fatal); 1100 } 1101 1102 /* now when the initialization is (almost) complete, chdir("/") 1103 * to free any busy filesystems */ 1104 if (chdir("/") < 0) { 1105 error_report("Could not chdir to root directory: %s", 1106 strerror(errno)); 1107 exit(EXIT_FAILURE); 1108 } 1109 1110 if (fork_process) { 1111 dup2(old_stderr, STDERR_FILENO); 1112 close(old_stderr); 1113 } 1114 1115 state = RUNNING; 1116 do { 1117 main_loop_wait(false); 1118 if (state == TERMINATE) { 1119 blk_exp_close_all(); 1120 state = TERMINATED; 1121 } 1122 } while (state != TERMINATED); 1123 1124 blk_unref(blk); 1125 if (sockpath) { 1126 unlink(sockpath); 1127 } 1128 1129 qemu_opts_del(sn_opts); 1130 1131 if (device) { 1132 void *ret; 1133 pthread_join(client_thread, &ret); 1134 exit(ret != NULL); 1135 } else { 1136 exit(EXIT_SUCCESS); 1137 } 1138 } 1139