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 " -A, --allocation-depth expose the allocation depth\n" 104 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 105 "\n" 106 "General purpose options:\n" 107 " -L, --list list exports available from another NBD server\n" 108 " --object type,id=ID,... define an object such as 'secret' for providing\n" 109 " passwords and/or encryption keys\n" 110 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 111 " --tls-authz=ID use id of an earlier --object to provide\n" 112 " authorization\n" 113 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 114 " specify tracing options\n" 115 " --fork fork off the server process and exit the parent\n" 116 " once the server is running\n" 117 " --pid-file=PATH store the server's process ID in the given file\n" 118 #if HAVE_NBD_DEVICE 119 "\n" 120 "Kernel NBD client support:\n" 121 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 122 " -d, --disconnect disconnect the specified device\n" 123 #endif 124 "\n" 125 "Block device options:\n" 126 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 127 " -r, --read-only export read-only\n" 128 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 129 " file with backing_file=FILE, redirect the write to\n" 130 " the temporary one\n" 131 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 132 " load an internal snapshot inside FILE and export it\n" 133 " as an read-only device, SNAPSHOT_PARAM format is\n" 134 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 135 " '[ID_OR_NAME]'\n" 136 " -n, --nocache disable host cache\n" 137 " --cache=MODE set cache mode (none, writeback, ...)\n" 138 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 139 " --discard=MODE set discard mode (ignore, unmap)\n" 140 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 141 " --image-opts treat FILE as a full set of image options\n" 142 "\n" 143 QEMU_HELP_BOTTOM "\n" 144 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 145 } 146 147 static void version(const char *name) 148 { 149 printf( 150 "%s " QEMU_FULL_VERSION "\n" 151 "Written by Anthony Liguori.\n" 152 "\n" 153 QEMU_COPYRIGHT "\n" 154 "This is free software; see the source for copying conditions. There is NO\n" 155 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 156 , name); 157 } 158 159 #ifdef CONFIG_POSIX 160 /* 161 * The client thread uses SIGTERM to interrupt the server. A signal 162 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 163 */ 164 void qemu_system_killed(int signum, pid_t pid) 165 { 166 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 167 qemu_notify_event(); 168 } 169 #endif /* CONFIG_POSIX */ 170 171 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 172 const char *hostname) 173 { 174 int ret = EXIT_FAILURE; 175 int rc; 176 Error *err = NULL; 177 QIOChannelSocket *sioc; 178 NBDExportInfo *list; 179 int i, j; 180 181 sioc = qio_channel_socket_new(); 182 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 183 error_report_err(err); 184 return EXIT_FAILURE; 185 } 186 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 187 &err); 188 if (rc < 0) { 189 if (err) { 190 error_report_err(err); 191 } 192 goto out; 193 } 194 printf("exports available: %d\n", rc); 195 for (i = 0; i < rc; i++) { 196 printf(" export: '%s'\n", list[i].name); 197 if (list[i].description && *list[i].description) { 198 printf(" description: %s\n", list[i].description); 199 } 200 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 201 static const char *const flag_names[] = { 202 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 203 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 204 [NBD_FLAG_SEND_FUA_BIT] = "fua", 205 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 206 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 207 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 208 [NBD_FLAG_SEND_DF_BIT] = "df", 209 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 210 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 211 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 212 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 213 }; 214 215 printf(" size: %" PRIu64 "\n", list[i].size); 216 printf(" flags: 0x%x (", list[i].flags); 217 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 218 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 219 printf(" %s", flag_names[bit]); 220 } 221 } 222 printf(" )\n"); 223 } 224 if (list[i].min_block) { 225 printf(" min block: %u\n", list[i].min_block); 226 printf(" opt block: %u\n", list[i].opt_block); 227 printf(" max block: %u\n", list[i].max_block); 228 } 229 if (list[i].n_contexts) { 230 printf(" available meta contexts: %d\n", list[i].n_contexts); 231 for (j = 0; j < list[i].n_contexts; j++) { 232 printf(" %s\n", list[i].contexts[j]); 233 } 234 } 235 } 236 nbd_free_export_list(list, rc); 237 238 ret = EXIT_SUCCESS; 239 out: 240 object_unref(OBJECT(sioc)); 241 return ret; 242 } 243 244 245 #if HAVE_NBD_DEVICE 246 static void *show_parts(void *arg) 247 { 248 char *device = arg; 249 int nbd; 250 251 /* linux just needs an open() to trigger 252 * the partition table update 253 * but remember to load the module with max_part != 0 : 254 * modprobe nbd max_part=63 255 */ 256 nbd = open(device, O_RDWR); 257 if (nbd >= 0) { 258 close(nbd); 259 } 260 return NULL; 261 } 262 263 static void *nbd_client_thread(void *arg) 264 { 265 char *device = arg; 266 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 267 QIOChannelSocket *sioc; 268 int fd; 269 int ret; 270 pthread_t show_parts_thread; 271 Error *local_error = NULL; 272 273 sioc = qio_channel_socket_new(); 274 if (qio_channel_socket_connect_sync(sioc, 275 saddr, 276 &local_error) < 0) { 277 error_report_err(local_error); 278 goto out; 279 } 280 281 ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 282 NULL, NULL, NULL, &info, &local_error); 283 if (ret < 0) { 284 if (local_error) { 285 error_report_err(local_error); 286 } 287 goto out_socket; 288 } 289 290 fd = open(device, O_RDWR); 291 if (fd < 0) { 292 /* Linux-only, we can use %m in printf. */ 293 error_report("Failed to open %s: %m", device); 294 goto out_socket; 295 } 296 297 ret = nbd_init(fd, sioc, &info, &local_error); 298 if (ret < 0) { 299 error_report_err(local_error); 300 goto out_fd; 301 } 302 303 /* update partition table */ 304 pthread_create(&show_parts_thread, NULL, show_parts, device); 305 306 if (verbose) { 307 fprintf(stderr, "NBD device %s is now connected to %s\n", 308 device, srcpath); 309 } else { 310 /* Close stderr so that the qemu-nbd process exits. */ 311 dup2(STDOUT_FILENO, STDERR_FILENO); 312 } 313 314 ret = nbd_client(fd); 315 if (ret) { 316 goto out_fd; 317 } 318 close(fd); 319 object_unref(OBJECT(sioc)); 320 g_free(info.name); 321 kill(getpid(), SIGTERM); 322 return (void *) EXIT_SUCCESS; 323 324 out_fd: 325 close(fd); 326 out_socket: 327 object_unref(OBJECT(sioc)); 328 out: 329 g_free(info.name); 330 kill(getpid(), SIGTERM); 331 return (void *) EXIT_FAILURE; 332 } 333 #endif /* HAVE_NBD_DEVICE */ 334 335 static int nbd_can_accept(void) 336 { 337 return state == RUNNING && nb_fds < shared; 338 } 339 340 static void nbd_update_server_watch(void); 341 342 static void nbd_client_closed(NBDClient *client, bool negotiated) 343 { 344 nb_fds--; 345 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 346 state = TERMINATE; 347 } 348 nbd_update_server_watch(); 349 nbd_client_put(client); 350 } 351 352 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 353 gpointer opaque) 354 { 355 if (state >= TERMINATE) { 356 return; 357 } 358 359 nb_fds++; 360 nbd_update_server_watch(); 361 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 362 } 363 364 static void nbd_update_server_watch(void) 365 { 366 if (nbd_can_accept()) { 367 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 368 } else { 369 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 370 } 371 } 372 373 374 static SocketAddress *nbd_build_socket_address(const char *sockpath, 375 const char *bindto, 376 const char *port) 377 { 378 SocketAddress *saddr; 379 380 saddr = g_new0(SocketAddress, 1); 381 if (sockpath) { 382 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 383 saddr->u.q_unix.path = g_strdup(sockpath); 384 } else { 385 InetSocketAddress *inet; 386 saddr->type = SOCKET_ADDRESS_TYPE_INET; 387 inet = &saddr->u.inet; 388 inet->host = g_strdup(bindto); 389 if (port) { 390 inet->port = g_strdup(port); 391 } else { 392 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 393 } 394 } 395 396 return saddr; 397 } 398 399 400 static QemuOptsList file_opts = { 401 .name = "file", 402 .implied_opt_name = "file", 403 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 404 .desc = { 405 /* no elements => accept any params */ 406 { /* end of list */ } 407 }, 408 }; 409 410 static QemuOptsList qemu_object_opts = { 411 .name = "object", 412 .implied_opt_name = "qom-type", 413 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 414 .desc = { 415 { } 416 }, 417 }; 418 419 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts) 420 { 421 if (user_creatable_print_help(type, opts)) { 422 exit(0); 423 } 424 return true; 425 } 426 427 428 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 429 Error **errp) 430 { 431 Object *obj; 432 QCryptoTLSCreds *creds; 433 434 obj = object_resolve_path_component( 435 object_get_objects_root(), id); 436 if (!obj) { 437 error_setg(errp, "No TLS credentials with id '%s'", 438 id); 439 return NULL; 440 } 441 creds = (QCryptoTLSCreds *) 442 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 443 if (!creds) { 444 error_setg(errp, "Object with id '%s' is not TLS credentials", 445 id); 446 return NULL; 447 } 448 449 if (list) { 450 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 451 error_setg(errp, 452 "Expecting TLS credentials with a client endpoint"); 453 return NULL; 454 } 455 } else { 456 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 457 error_setg(errp, 458 "Expecting TLS credentials with a server endpoint"); 459 return NULL; 460 } 461 } 462 object_ref(obj); 463 return creds; 464 } 465 466 static void setup_address_and_port(const char **address, const char **port) 467 { 468 if (*address == NULL) { 469 *address = "0.0.0.0"; 470 } 471 472 if (*port == NULL) { 473 *port = stringify(NBD_DEFAULT_PORT); 474 } 475 } 476 477 /* 478 * Check socket parameters compatibility when socket activation is used. 479 */ 480 static const char *socket_activation_validate_opts(const char *device, 481 const char *sockpath, 482 const char *address, 483 const char *port, 484 bool list) 485 { 486 if (device != NULL) { 487 return "NBD device can't be set when using socket activation"; 488 } 489 490 if (sockpath != NULL) { 491 return "Unix socket can't be set when using socket activation"; 492 } 493 494 if (address != NULL) { 495 return "The interface can't be set when using socket activation"; 496 } 497 498 if (port != NULL) { 499 return "TCP port number can't be set when using socket activation"; 500 } 501 502 if (list) { 503 return "List mode is incompatible with socket activation"; 504 } 505 506 return NULL; 507 } 508 509 static void qemu_nbd_shutdown(void) 510 { 511 job_cancel_sync_all(); 512 bdrv_close_all(); 513 } 514 515 int main(int argc, char **argv) 516 { 517 BlockBackend *blk; 518 BlockDriverState *bs; 519 uint64_t dev_offset = 0; 520 bool readonly = false; 521 bool disconnect = false; 522 const char *bindto = NULL; 523 const char *port = NULL; 524 char *sockpath = NULL; 525 char *device = NULL; 526 QemuOpts *sn_opts = NULL; 527 const char *sn_id_or_name = NULL; 528 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 529 struct option lopt[] = { 530 { "help", no_argument, NULL, 'h' }, 531 { "version", no_argument, NULL, 'V' }, 532 { "bind", required_argument, NULL, 'b' }, 533 { "port", required_argument, NULL, 'p' }, 534 { "socket", required_argument, NULL, 'k' }, 535 { "offset", required_argument, NULL, 'o' }, 536 { "read-only", no_argument, NULL, 'r' }, 537 { "allocation-depth", no_argument, NULL, 'A' }, 538 { "bitmap", required_argument, NULL, 'B' }, 539 { "connect", required_argument, NULL, 'c' }, 540 { "disconnect", no_argument, NULL, 'd' }, 541 { "list", no_argument, NULL, 'L' }, 542 { "snapshot", no_argument, NULL, 's' }, 543 { "load-snapshot", required_argument, NULL, 'l' }, 544 { "nocache", no_argument, NULL, 'n' }, 545 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 546 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 547 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 548 { "detect-zeroes", required_argument, NULL, 549 QEMU_NBD_OPT_DETECT_ZEROES }, 550 { "shared", required_argument, NULL, 'e' }, 551 { "format", required_argument, NULL, 'f' }, 552 { "persistent", no_argument, NULL, 't' }, 553 { "verbose", no_argument, NULL, 'v' }, 554 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 555 { "export-name", required_argument, NULL, 'x' }, 556 { "description", required_argument, NULL, 'D' }, 557 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 558 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 559 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 560 { "trace", required_argument, NULL, 'T' }, 561 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 562 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 563 { NULL, 0, NULL, 0 } 564 }; 565 int ch; 566 int opt_ind = 0; 567 int flags = BDRV_O_RDWR; 568 int ret = 0; 569 bool seen_cache = false; 570 bool seen_discard = false; 571 bool seen_aio = false; 572 pthread_t client_thread; 573 const char *fmt = NULL; 574 Error *local_err = NULL; 575 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 576 QDict *options = NULL; 577 const char *export_name = NULL; /* defaults to "" later for server mode */ 578 const char *export_description = NULL; 579 strList *bitmaps = NULL; 580 bool alloc_depth = false; 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 BlockExportOptions *export_opts; 591 592 #ifdef CONFIG_POSIX 593 os_setup_early_signal_handling(); 594 os_setup_signal_handling(); 595 #endif 596 597 socket_init(); 598 error_init(argv[0]); 599 module_call_init(MODULE_INIT_TRACE); 600 qcrypto_init(&error_fatal); 601 602 module_call_init(MODULE_INIT_QOM); 603 qemu_add_opts(&qemu_object_opts); 604 qemu_add_opts(&qemu_trace_opts); 605 qemu_init_exec_dir(argv[0]); 606 607 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 608 switch (ch) { 609 case 's': 610 flags |= BDRV_O_SNAPSHOT; 611 break; 612 case 'n': 613 optarg = (char *) "none"; 614 /* fallthrough */ 615 case QEMU_NBD_OPT_CACHE: 616 if (seen_cache) { 617 error_report("-n and --cache can only be specified once"); 618 exit(EXIT_FAILURE); 619 } 620 seen_cache = true; 621 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 622 error_report("Invalid cache mode `%s'", optarg); 623 exit(EXIT_FAILURE); 624 } 625 break; 626 case QEMU_NBD_OPT_AIO: 627 if (seen_aio) { 628 error_report("--aio can only be specified once"); 629 exit(EXIT_FAILURE); 630 } 631 seen_aio = true; 632 if (bdrv_parse_aio(optarg, &flags) < 0) { 633 error_report("Invalid aio mode '%s'", optarg); 634 exit(EXIT_FAILURE); 635 } 636 break; 637 case QEMU_NBD_OPT_DISCARD: 638 if (seen_discard) { 639 error_report("--discard can only be specified once"); 640 exit(EXIT_FAILURE); 641 } 642 seen_discard = true; 643 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 644 error_report("Invalid discard mode `%s'", optarg); 645 exit(EXIT_FAILURE); 646 } 647 break; 648 case QEMU_NBD_OPT_DETECT_ZEROES: 649 detect_zeroes = 650 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 651 optarg, 652 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 653 &local_err); 654 if (local_err) { 655 error_reportf_err(local_err, 656 "Failed to parse detect_zeroes mode: "); 657 exit(EXIT_FAILURE); 658 } 659 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 660 !(flags & BDRV_O_UNMAP)) { 661 error_report("setting detect-zeroes to unmap is not allowed " 662 "without setting discard operation to unmap"); 663 exit(EXIT_FAILURE); 664 } 665 break; 666 case 'b': 667 bindto = optarg; 668 break; 669 case 'p': 670 port = optarg; 671 break; 672 case 'o': 673 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 674 error_report("Invalid offset '%s'", optarg); 675 exit(EXIT_FAILURE); 676 } 677 break; 678 case 'l': 679 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 680 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 681 optarg, false); 682 if (!sn_opts) { 683 error_report("Failed in parsing snapshot param `%s'", 684 optarg); 685 exit(EXIT_FAILURE); 686 } 687 } else { 688 sn_id_or_name = optarg; 689 } 690 /* fall through */ 691 case 'r': 692 readonly = true; 693 flags &= ~BDRV_O_RDWR; 694 break; 695 case 'A': 696 alloc_depth = true; 697 break; 698 case 'B': 699 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg)); 700 break; 701 case 'k': 702 sockpath = optarg; 703 if (sockpath[0] != '/') { 704 error_report("socket path must be absolute"); 705 exit(EXIT_FAILURE); 706 } 707 break; 708 case 'd': 709 disconnect = true; 710 break; 711 case 'c': 712 device = optarg; 713 break; 714 case 'e': 715 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 716 shared < 1) { 717 error_report("Invalid shared device number '%s'", optarg); 718 exit(EXIT_FAILURE); 719 } 720 break; 721 case 'f': 722 fmt = optarg; 723 break; 724 case 't': 725 persistent = 1; 726 break; 727 case 'x': 728 export_name = optarg; 729 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 730 error_report("export name '%s' too long", export_name); 731 exit(EXIT_FAILURE); 732 } 733 break; 734 case 'D': 735 export_description = optarg; 736 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 737 error_report("export description '%s' too long", 738 export_description); 739 exit(EXIT_FAILURE); 740 } 741 break; 742 case 'v': 743 verbose = 1; 744 break; 745 case 'V': 746 version(argv[0]); 747 exit(0); 748 break; 749 case 'h': 750 usage(argv[0]); 751 exit(0); 752 break; 753 case '?': 754 error_report("Try `%s --help' for more information.", argv[0]); 755 exit(EXIT_FAILURE); 756 case QEMU_NBD_OPT_OBJECT: { 757 QemuOpts *opts; 758 opts = qemu_opts_parse_noisily(&qemu_object_opts, 759 optarg, true); 760 if (!opts) { 761 exit(EXIT_FAILURE); 762 } 763 } break; 764 case QEMU_NBD_OPT_TLSCREDS: 765 tlscredsid = optarg; 766 break; 767 case QEMU_NBD_OPT_IMAGE_OPTS: 768 imageOpts = true; 769 break; 770 case 'T': 771 g_free(trace_file); 772 trace_file = trace_opt_parse(optarg); 773 break; 774 case QEMU_NBD_OPT_TLSAUTHZ: 775 tlsauthz = optarg; 776 break; 777 case QEMU_NBD_OPT_FORK: 778 fork_process = true; 779 break; 780 case 'L': 781 list = true; 782 break; 783 case QEMU_NBD_OPT_PID_FILE: 784 pid_file_name = optarg; 785 break; 786 } 787 } 788 789 if (list) { 790 if (argc != optind) { 791 error_report("List mode is incompatible with a file name"); 792 exit(EXIT_FAILURE); 793 } 794 if (export_name || export_description || dev_offset || 795 device || disconnect || fmt || sn_id_or_name || bitmaps || 796 alloc_depth || seen_aio || seen_discard || seen_cache) { 797 error_report("List mode is incompatible with per-device settings"); 798 exit(EXIT_FAILURE); 799 } 800 if (fork_process) { 801 error_report("List mode is incompatible with forking"); 802 exit(EXIT_FAILURE); 803 } 804 } else if ((argc - optind) != 1) { 805 error_report("Invalid number of arguments"); 806 error_printf("Try `%s --help' for more information.\n", argv[0]); 807 exit(EXIT_FAILURE); 808 } else if (!export_name) { 809 export_name = ""; 810 } 811 812 qemu_opts_foreach(&qemu_object_opts, 813 user_creatable_add_opts_foreach, 814 qemu_nbd_object_print_help, &error_fatal); 815 816 if (!trace_init_backends()) { 817 exit(1); 818 } 819 trace_init_file(trace_file); 820 qemu_set_log(LOG_TRACE); 821 822 socket_activation = check_socket_activation(); 823 if (socket_activation == 0) { 824 setup_address_and_port(&bindto, &port); 825 } else { 826 /* Using socket activation - check user didn't use -p etc. */ 827 const char *err_msg = socket_activation_validate_opts(device, sockpath, 828 bindto, port, 829 list); 830 if (err_msg != NULL) { 831 error_report("%s", err_msg); 832 exit(EXIT_FAILURE); 833 } 834 835 /* qemu-nbd can only listen on a single socket. */ 836 if (socket_activation > 1) { 837 error_report("qemu-nbd does not support socket activation with %s > 1", 838 "LISTEN_FDS"); 839 exit(EXIT_FAILURE); 840 } 841 } 842 843 if (tlscredsid) { 844 if (sockpath) { 845 error_report("TLS is only supported with IPv4/IPv6"); 846 exit(EXIT_FAILURE); 847 } 848 if (device) { 849 error_report("TLS is not supported with a host device"); 850 exit(EXIT_FAILURE); 851 } 852 if (tlsauthz && list) { 853 error_report("TLS authorization is incompatible with export list"); 854 exit(EXIT_FAILURE); 855 } 856 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 857 if (local_err) { 858 error_reportf_err(local_err, "Failed to get TLS creds: "); 859 exit(EXIT_FAILURE); 860 } 861 } else { 862 if (tlsauthz) { 863 error_report("--tls-authz is not permitted without --tls-creds"); 864 exit(EXIT_FAILURE); 865 } 866 } 867 868 if (list) { 869 saddr = nbd_build_socket_address(sockpath, bindto, port); 870 return qemu_nbd_client_list(saddr, tlscreds, bindto); 871 } 872 873 #if !HAVE_NBD_DEVICE 874 if (disconnect || device) { 875 error_report("Kernel /dev/nbdN support not available"); 876 exit(EXIT_FAILURE); 877 } 878 #else /* HAVE_NBD_DEVICE */ 879 if (disconnect) { 880 int nbdfd = open(argv[optind], O_RDWR); 881 if (nbdfd < 0) { 882 error_report("Cannot open %s: %s", argv[optind], 883 strerror(errno)); 884 exit(EXIT_FAILURE); 885 } 886 nbd_disconnect(nbdfd); 887 888 close(nbdfd); 889 890 printf("%s disconnected\n", argv[optind]); 891 892 return 0; 893 } 894 #endif 895 896 if ((device && !verbose) || fork_process) { 897 #ifndef WIN32 898 int stderr_fd[2]; 899 pid_t pid; 900 int ret; 901 902 if (qemu_pipe(stderr_fd) < 0) { 903 error_report("Error setting up communication pipe: %s", 904 strerror(errno)); 905 exit(EXIT_FAILURE); 906 } 907 908 /* Now daemonize, but keep a communication channel open to 909 * print errors and exit with the proper status code. 910 */ 911 pid = fork(); 912 if (pid < 0) { 913 error_report("Failed to fork: %s", strerror(errno)); 914 exit(EXIT_FAILURE); 915 } else if (pid == 0) { 916 close(stderr_fd[0]); 917 918 /* Remember parent's stderr if we will be restoring it. */ 919 if (fork_process) { 920 old_stderr = dup(STDERR_FILENO); 921 } 922 923 ret = qemu_daemon(1, 0); 924 925 /* Temporarily redirect stderr to the parent's pipe... */ 926 dup2(stderr_fd[1], STDERR_FILENO); 927 if (ret < 0) { 928 error_report("Failed to daemonize: %s", strerror(errno)); 929 exit(EXIT_FAILURE); 930 } 931 932 /* ... close the descriptor we inherited and go on. */ 933 close(stderr_fd[1]); 934 } else { 935 bool errors = false; 936 char *buf; 937 938 /* In the parent. Print error messages from the child until 939 * it closes the pipe. 940 */ 941 close(stderr_fd[1]); 942 buf = g_malloc(1024); 943 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 944 errors = true; 945 ret = qemu_write_full(STDERR_FILENO, buf, ret); 946 if (ret < 0) { 947 exit(EXIT_FAILURE); 948 } 949 } 950 if (ret < 0) { 951 error_report("Cannot read from daemon: %s", 952 strerror(errno)); 953 exit(EXIT_FAILURE); 954 } 955 956 /* Usually the daemon should not print any message. 957 * Exit with zero status in that case. 958 */ 959 exit(errors); 960 } 961 #else /* WIN32 */ 962 error_report("Unable to fork into background on Windows hosts"); 963 exit(EXIT_FAILURE); 964 #endif /* WIN32 */ 965 } 966 967 if (device != NULL && sockpath == NULL) { 968 sockpath = g_malloc(128); 969 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 970 } 971 972 server = qio_net_listener_new(); 973 if (socket_activation == 0) { 974 saddr = nbd_build_socket_address(sockpath, bindto, port); 975 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) { 976 object_unref(OBJECT(server)); 977 error_report_err(local_err); 978 exit(EXIT_FAILURE); 979 } 980 } else { 981 size_t i; 982 /* See comment in check_socket_activation above. */ 983 for (i = 0; i < socket_activation; i++) { 984 QIOChannelSocket *sioc; 985 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 986 &local_err); 987 if (sioc == NULL) { 988 object_unref(OBJECT(server)); 989 error_reportf_err(local_err, 990 "Failed to use socket activation: "); 991 exit(EXIT_FAILURE); 992 } 993 qio_net_listener_add(server, sioc); 994 object_unref(OBJECT(sioc)); 995 } 996 } 997 998 if (qemu_init_main_loop(&local_err)) { 999 error_report_err(local_err); 1000 exit(EXIT_FAILURE); 1001 } 1002 bdrv_init(); 1003 atexit(qemu_nbd_shutdown); 1004 1005 srcpath = argv[optind]; 1006 if (imageOpts) { 1007 QemuOpts *opts; 1008 if (fmt) { 1009 error_report("--image-opts and -f are mutually exclusive"); 1010 exit(EXIT_FAILURE); 1011 } 1012 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1013 if (!opts) { 1014 qemu_opts_reset(&file_opts); 1015 exit(EXIT_FAILURE); 1016 } 1017 options = qemu_opts_to_qdict(opts, NULL); 1018 qemu_opts_reset(&file_opts); 1019 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1020 } else { 1021 if (fmt) { 1022 options = qdict_new(); 1023 qdict_put_str(options, "driver", fmt); 1024 } 1025 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1026 } 1027 1028 if (!blk) { 1029 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1030 argv[optind]); 1031 exit(EXIT_FAILURE); 1032 } 1033 bs = blk_bs(blk); 1034 1035 if (dev_offset) { 1036 QDict *raw_opts = qdict_new(); 1037 qdict_put_str(raw_opts, "driver", "raw"); 1038 qdict_put_str(raw_opts, "file", bs->node_name); 1039 qdict_put_int(raw_opts, "offset", dev_offset); 1040 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1041 blk_remove_bs(blk); 1042 blk_insert_bs(blk, bs, &error_fatal); 1043 bdrv_unref(bs); 1044 } 1045 1046 blk_set_enable_write_cache(blk, !writethrough); 1047 1048 if (sn_opts) { 1049 ret = bdrv_snapshot_load_tmp(bs, 1050 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1051 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1052 &local_err); 1053 } else if (sn_id_or_name) { 1054 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1055 &local_err); 1056 } 1057 if (ret < 0) { 1058 error_reportf_err(local_err, "Failed to load snapshot: "); 1059 exit(EXIT_FAILURE); 1060 } 1061 1062 bs->detect_zeroes = detect_zeroes; 1063 1064 nbd_server_is_qemu_nbd(true); 1065 1066 export_opts = g_new(BlockExportOptions, 1); 1067 *export_opts = (BlockExportOptions) { 1068 .type = BLOCK_EXPORT_TYPE_NBD, 1069 .id = g_strdup("qemu-nbd-export"), 1070 .node_name = g_strdup(bdrv_get_node_name(bs)), 1071 .has_writethrough = true, 1072 .writethrough = writethrough, 1073 .has_writable = true, 1074 .writable = !readonly, 1075 .u.nbd = { 1076 .has_name = true, 1077 .name = g_strdup(export_name), 1078 .has_description = !!export_description, 1079 .description = g_strdup(export_description), 1080 .has_bitmaps = !!bitmaps, 1081 .bitmaps = bitmaps, 1082 .has_allocation_depth = alloc_depth, 1083 .allocation_depth = alloc_depth, 1084 }, 1085 }; 1086 blk_exp_add(export_opts, &error_fatal); 1087 qapi_free_BlockExportOptions(export_opts); 1088 1089 if (device) { 1090 #if HAVE_NBD_DEVICE 1091 int ret; 1092 1093 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1094 if (ret != 0) { 1095 error_report("Failed to create client thread: %s", strerror(ret)); 1096 exit(EXIT_FAILURE); 1097 } 1098 #endif 1099 } else { 1100 /* Shut up GCC warnings. */ 1101 memset(&client_thread, 0, sizeof(client_thread)); 1102 } 1103 1104 nbd_update_server_watch(); 1105 1106 if (pid_file_name) { 1107 qemu_write_pidfile(pid_file_name, &error_fatal); 1108 } 1109 1110 /* now when the initialization is (almost) complete, chdir("/") 1111 * to free any busy filesystems */ 1112 if (chdir("/") < 0) { 1113 error_report("Could not chdir to root directory: %s", 1114 strerror(errno)); 1115 exit(EXIT_FAILURE); 1116 } 1117 1118 if (fork_process) { 1119 dup2(old_stderr, STDERR_FILENO); 1120 close(old_stderr); 1121 } 1122 1123 state = RUNNING; 1124 do { 1125 main_loop_wait(false); 1126 if (state == TERMINATE) { 1127 blk_exp_close_all(); 1128 state = TERMINATED; 1129 } 1130 } while (state != TERMINATED); 1131 1132 blk_unref(blk); 1133 if (sockpath) { 1134 unlink(sockpath); 1135 } 1136 1137 qemu_opts_del(sn_opts); 1138 1139 if (device) { 1140 void *ret; 1141 pthread_join(client_thread, &ret); 1142 exit(ret != NULL); 1143 } else { 1144 exit(EXIT_SUCCESS); 1145 } 1146 } 1147