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 "qapi/error.h" 25 #include "qemu/cutils.h" 26 #include "sysemu/block-backend.h" 27 #include "block/block_int.h" 28 #include "block/nbd.h" 29 #include "qemu/main-loop.h" 30 #include "qemu/option.h" 31 #include "qemu/error-report.h" 32 #include "qemu/config-file.h" 33 #include "qemu/bswap.h" 34 #include "qemu/log.h" 35 #include "qemu/systemd.h" 36 #include "block/snapshot.h" 37 #include "qapi/qmp/qdict.h" 38 #include "qapi/qmp/qstring.h" 39 #include "qom/object_interfaces.h" 40 #include "io/channel-socket.h" 41 #include "io/net-listener.h" 42 #include "crypto/init.h" 43 #include "trace/control.h" 44 #include "qemu-version.h" 45 46 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 47 #define QEMU_NBD_OPT_CACHE 256 48 #define QEMU_NBD_OPT_AIO 257 49 #define QEMU_NBD_OPT_DISCARD 258 50 #define QEMU_NBD_OPT_DETECT_ZEROES 259 51 #define QEMU_NBD_OPT_OBJECT 260 52 #define QEMU_NBD_OPT_TLSCREDS 261 53 #define QEMU_NBD_OPT_IMAGE_OPTS 262 54 #define QEMU_NBD_OPT_FORK 263 55 56 #define MBR_SIZE 512 57 58 static NBDExport *exp; 59 static bool newproto; 60 static int verbose; 61 static char *srcpath; 62 static SocketAddress *saddr; 63 static int persistent = 0; 64 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 65 static int shared = 1; 66 static int nb_fds; 67 static QIONetListener *server; 68 static QCryptoTLSCreds *tlscreds; 69 70 static void usage(const char *name) 71 { 72 (printf) ( 73 "Usage: %s [OPTIONS] FILE\n" 74 "QEMU Disk Network Block Device Server\n" 75 "\n" 76 " -h, --help display this help and exit\n" 77 " -V, --version output version information and exit\n" 78 "\n" 79 "Connection properties:\n" 80 " -p, --port=PORT port to listen on (default `%d')\n" 81 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 82 " -k, --socket=PATH path to the unix socket\n" 83 " (default '"SOCKET_PATH"')\n" 84 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 85 " -t, --persistent don't exit on the last connection\n" 86 " -v, --verbose display extra debugging information\n" 87 " -x, --export-name=NAME expose export by name\n" 88 " -D, --description=TEXT with -x, also export a human-readable description\n" 89 "\n" 90 "Exposing part of the image:\n" 91 " -o, --offset=OFFSET offset into the image\n" 92 " -P, --partition=NUM only expose partition NUM\n" 93 "\n" 94 "General purpose options:\n" 95 " --object type,id=ID,... define an object such as 'secret' for providing\n" 96 " passwords and/or encryption keys\n" 97 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 98 " specify tracing options\n" 99 " --fork fork off the server process and exit the parent\n" 100 " once the server is running\n" 101 #ifdef __linux__ 102 "Kernel NBD client support:\n" 103 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 104 " -d, --disconnect disconnect the specified device\n" 105 "\n" 106 #endif 107 "\n" 108 "Block device options:\n" 109 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 110 " -r, --read-only export read-only\n" 111 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 112 " file with backing_file=FILE, redirect the write to\n" 113 " the temporary one\n" 114 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 115 " load an internal snapshot inside FILE and export it\n" 116 " as an read-only device, SNAPSHOT_PARAM format is\n" 117 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 118 " '[ID_OR_NAME]'\n" 119 " -n, --nocache disable host cache\n" 120 " --cache=MODE set cache mode (none, writeback, ...)\n" 121 " --aio=MODE set AIO mode (native or threads)\n" 122 " --discard=MODE set discard mode (ignore, unmap)\n" 123 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 124 " --image-opts treat FILE as a full set of image options\n" 125 "\n" 126 QEMU_HELP_BOTTOM "\n" 127 , name, NBD_DEFAULT_PORT, "DEVICE"); 128 } 129 130 static void version(const char *name) 131 { 132 printf( 133 "%s " QEMU_VERSION QEMU_PKGVERSION "\n" 134 "Written by Anthony Liguori.\n" 135 "\n" 136 QEMU_COPYRIGHT "\n" 137 "This is free software; see the source for copying conditions. There is NO\n" 138 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 139 , name); 140 } 141 142 struct partition_record 143 { 144 uint8_t bootable; 145 uint8_t start_head; 146 uint32_t start_cylinder; 147 uint8_t start_sector; 148 uint8_t system; 149 uint8_t end_head; 150 uint8_t end_cylinder; 151 uint8_t end_sector; 152 uint32_t start_sector_abs; 153 uint32_t nb_sectors_abs; 154 }; 155 156 static void read_partition(uint8_t *p, struct partition_record *r) 157 { 158 r->bootable = p[0]; 159 r->start_head = p[1]; 160 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 161 r->start_sector = p[2] & 0x3f; 162 r->system = p[4]; 163 r->end_head = p[5]; 164 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 165 r->end_sector = p[6] & 0x3f; 166 167 r->start_sector_abs = ldl_le_p(p + 8); 168 r->nb_sectors_abs = ldl_le_p(p + 12); 169 } 170 171 static int find_partition(BlockBackend *blk, int partition, 172 off_t *offset, off_t *size) 173 { 174 struct partition_record mbr[4]; 175 uint8_t data[MBR_SIZE]; 176 int i; 177 int ext_partnum = 4; 178 int ret; 179 180 ret = blk_pread(blk, 0, data, sizeof(data)); 181 if (ret < 0) { 182 error_report("error while reading: %s", strerror(-ret)); 183 exit(EXIT_FAILURE); 184 } 185 186 if (data[510] != 0x55 || data[511] != 0xaa) { 187 return -EINVAL; 188 } 189 190 for (i = 0; i < 4; i++) { 191 read_partition(&data[446 + 16 * i], &mbr[i]); 192 193 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 194 continue; 195 } 196 197 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 198 struct partition_record ext[4]; 199 uint8_t data1[MBR_SIZE]; 200 int j; 201 202 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, 203 data1, sizeof(data1)); 204 if (ret < 0) { 205 error_report("error while reading: %s", strerror(-ret)); 206 exit(EXIT_FAILURE); 207 } 208 209 for (j = 0; j < 4; j++) { 210 read_partition(&data1[446 + 16 * j], &ext[j]); 211 if (!ext[j].system || !ext[j].nb_sectors_abs) { 212 continue; 213 } 214 215 if ((ext_partnum + j + 1) == partition) { 216 *offset = (uint64_t)ext[j].start_sector_abs << 9; 217 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 218 return 0; 219 } 220 } 221 ext_partnum += 4; 222 } else if ((i + 1) == partition) { 223 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 224 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 225 return 0; 226 } 227 } 228 229 return -ENOENT; 230 } 231 232 static void termsig_handler(int signum) 233 { 234 atomic_cmpxchg(&state, RUNNING, TERMINATE); 235 qemu_notify_event(); 236 } 237 238 239 static void *show_parts(void *arg) 240 { 241 char *device = arg; 242 int nbd; 243 244 /* linux just needs an open() to trigger 245 * the partition table update 246 * but remember to load the module with max_part != 0 : 247 * modprobe nbd max_part=63 248 */ 249 nbd = open(device, O_RDWR); 250 if (nbd >= 0) { 251 close(nbd); 252 } 253 return NULL; 254 } 255 256 static void *nbd_client_thread(void *arg) 257 { 258 char *device = arg; 259 NBDExportInfo info = { .request_sizes = false, }; 260 QIOChannelSocket *sioc; 261 int fd; 262 int ret; 263 pthread_t show_parts_thread; 264 Error *local_error = NULL; 265 266 sioc = qio_channel_socket_new(); 267 if (qio_channel_socket_connect_sync(sioc, 268 saddr, 269 &local_error) < 0) { 270 error_report_err(local_error); 271 goto out; 272 } 273 274 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, 275 NULL, NULL, NULL, &info, &local_error); 276 if (ret < 0) { 277 if (local_error) { 278 error_report_err(local_error); 279 } 280 goto out_socket; 281 } 282 283 fd = open(device, O_RDWR); 284 if (fd < 0) { 285 /* Linux-only, we can use %m in printf. */ 286 error_report("Failed to open %s: %m", device); 287 goto out_socket; 288 } 289 290 ret = nbd_init(fd, sioc, &info, &local_error); 291 if (ret < 0) { 292 error_report_err(local_error); 293 goto out_fd; 294 } 295 296 /* update partition table */ 297 pthread_create(&show_parts_thread, NULL, show_parts, device); 298 299 if (verbose) { 300 fprintf(stderr, "NBD device %s is now connected to %s\n", 301 device, srcpath); 302 } else { 303 /* Close stderr so that the qemu-nbd process exits. */ 304 dup2(STDOUT_FILENO, STDERR_FILENO); 305 } 306 307 ret = nbd_client(fd); 308 if (ret) { 309 goto out_fd; 310 } 311 close(fd); 312 object_unref(OBJECT(sioc)); 313 kill(getpid(), SIGTERM); 314 return (void *) EXIT_SUCCESS; 315 316 out_fd: 317 close(fd); 318 out_socket: 319 object_unref(OBJECT(sioc)); 320 out: 321 kill(getpid(), SIGTERM); 322 return (void *) EXIT_FAILURE; 323 } 324 325 static int nbd_can_accept(void) 326 { 327 return state == RUNNING && nb_fds < shared; 328 } 329 330 static void nbd_export_closed(NBDExport *exp) 331 { 332 assert(state == TERMINATING); 333 state = TERMINATED; 334 } 335 336 static void nbd_update_server_watch(void); 337 338 static void nbd_client_closed(NBDClient *client, bool negotiated) 339 { 340 nb_fds--; 341 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 342 state = TERMINATE; 343 } 344 nbd_update_server_watch(); 345 nbd_client_put(client); 346 } 347 348 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 349 gpointer opaque) 350 { 351 if (state >= TERMINATE) { 352 return; 353 } 354 355 nb_fds++; 356 nbd_update_server_watch(); 357 nbd_client_new(newproto ? NULL : exp, cioc, 358 tlscreds, NULL, nbd_client_closed); 359 } 360 361 static void nbd_update_server_watch(void) 362 { 363 if (nbd_can_accept()) { 364 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 365 } else { 366 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 367 } 368 } 369 370 371 static SocketAddress *nbd_build_socket_address(const char *sockpath, 372 const char *bindto, 373 const char *port) 374 { 375 SocketAddress *saddr; 376 377 saddr = g_new0(SocketAddress, 1); 378 if (sockpath) { 379 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 380 saddr->u.q_unix.path = g_strdup(sockpath); 381 } else { 382 InetSocketAddress *inet; 383 saddr->type = SOCKET_ADDRESS_TYPE_INET; 384 inet = &saddr->u.inet; 385 inet->host = g_strdup(bindto); 386 if (port) { 387 inet->port = g_strdup(port); 388 } else { 389 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 390 } 391 } 392 393 return saddr; 394 } 395 396 397 static QemuOptsList file_opts = { 398 .name = "file", 399 .implied_opt_name = "file", 400 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 401 .desc = { 402 /* no elements => accept any params */ 403 { /* end of list */ } 404 }, 405 }; 406 407 static QemuOptsList qemu_object_opts = { 408 .name = "object", 409 .implied_opt_name = "qom-type", 410 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 411 .desc = { 412 { } 413 }, 414 }; 415 416 417 418 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 419 { 420 Object *obj; 421 QCryptoTLSCreds *creds; 422 423 obj = object_resolve_path_component( 424 object_get_objects_root(), id); 425 if (!obj) { 426 error_setg(errp, "No TLS credentials with id '%s'", 427 id); 428 return NULL; 429 } 430 creds = (QCryptoTLSCreds *) 431 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 432 if (!creds) { 433 error_setg(errp, "Object with id '%s' is not TLS credentials", 434 id); 435 return NULL; 436 } 437 438 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 439 error_setg(errp, 440 "Expecting TLS credentials with a server endpoint"); 441 return NULL; 442 } 443 object_ref(obj); 444 return creds; 445 } 446 447 static void setup_address_and_port(const char **address, const char **port) 448 { 449 if (*address == NULL) { 450 *address = "0.0.0.0"; 451 } 452 453 if (*port == NULL) { 454 *port = stringify(NBD_DEFAULT_PORT); 455 } 456 } 457 458 /* 459 * Check socket parameters compatibility when socket activation is used. 460 */ 461 static const char *socket_activation_validate_opts(const char *device, 462 const char *sockpath, 463 const char *address, 464 const char *port) 465 { 466 if (device != NULL) { 467 return "NBD device can't be set when using socket activation"; 468 } 469 470 if (sockpath != NULL) { 471 return "Unix socket can't be set when using socket activation"; 472 } 473 474 if (address != NULL) { 475 return "The interface can't be set when using socket activation"; 476 } 477 478 if (port != NULL) { 479 return "TCP port number can't be set when using socket activation"; 480 } 481 482 return NULL; 483 } 484 485 int main(int argc, char **argv) 486 { 487 BlockBackend *blk; 488 BlockDriverState *bs; 489 off_t dev_offset = 0; 490 uint16_t nbdflags = 0; 491 bool disconnect = false; 492 const char *bindto = NULL; 493 const char *port = NULL; 494 char *sockpath = NULL; 495 char *device = NULL; 496 off_t fd_size; 497 QemuOpts *sn_opts = NULL; 498 const char *sn_id_or_name = NULL; 499 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; 500 struct option lopt[] = { 501 { "help", no_argument, NULL, 'h' }, 502 { "version", no_argument, NULL, 'V' }, 503 { "bind", required_argument, NULL, 'b' }, 504 { "port", required_argument, NULL, 'p' }, 505 { "socket", required_argument, NULL, 'k' }, 506 { "offset", required_argument, NULL, 'o' }, 507 { "read-only", no_argument, NULL, 'r' }, 508 { "partition", required_argument, NULL, 'P' }, 509 { "connect", required_argument, NULL, 'c' }, 510 { "disconnect", no_argument, NULL, 'd' }, 511 { "snapshot", no_argument, NULL, 's' }, 512 { "load-snapshot", required_argument, NULL, 'l' }, 513 { "nocache", no_argument, NULL, 'n' }, 514 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 515 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 516 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 517 { "detect-zeroes", required_argument, NULL, 518 QEMU_NBD_OPT_DETECT_ZEROES }, 519 { "shared", required_argument, NULL, 'e' }, 520 { "format", required_argument, NULL, 'f' }, 521 { "persistent", no_argument, NULL, 't' }, 522 { "verbose", no_argument, NULL, 'v' }, 523 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 524 { "export-name", required_argument, NULL, 'x' }, 525 { "description", required_argument, NULL, 'D' }, 526 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 527 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 528 { "trace", required_argument, NULL, 'T' }, 529 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 530 { NULL, 0, NULL, 0 } 531 }; 532 int ch; 533 int opt_ind = 0; 534 char *end; 535 int flags = BDRV_O_RDWR; 536 int partition = -1; 537 int ret = 0; 538 bool seen_cache = false; 539 bool seen_discard = false; 540 bool seen_aio = false; 541 pthread_t client_thread; 542 const char *fmt = NULL; 543 Error *local_err = NULL; 544 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 545 QDict *options = NULL; 546 const char *export_name = NULL; 547 const char *export_description = NULL; 548 const char *tlscredsid = NULL; 549 bool imageOpts = false; 550 bool writethrough = true; 551 char *trace_file = NULL; 552 bool fork_process = false; 553 int old_stderr = -1; 554 unsigned socket_activation; 555 556 /* The client thread uses SIGTERM to interrupt the server. A signal 557 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 558 */ 559 struct sigaction sa_sigterm; 560 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 561 sa_sigterm.sa_handler = termsig_handler; 562 sigaction(SIGTERM, &sa_sigterm, NULL); 563 564 #ifdef CONFIG_POSIX 565 signal(SIGPIPE, SIG_IGN); 566 #endif 567 568 module_call_init(MODULE_INIT_TRACE); 569 qcrypto_init(&error_fatal); 570 571 module_call_init(MODULE_INIT_QOM); 572 qemu_add_opts(&qemu_object_opts); 573 qemu_add_opts(&qemu_trace_opts); 574 qemu_init_exec_dir(argv[0]); 575 576 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 577 switch (ch) { 578 case 's': 579 flags |= BDRV_O_SNAPSHOT; 580 break; 581 case 'n': 582 optarg = (char *) "none"; 583 /* fallthrough */ 584 case QEMU_NBD_OPT_CACHE: 585 if (seen_cache) { 586 error_report("-n and --cache can only be specified once"); 587 exit(EXIT_FAILURE); 588 } 589 seen_cache = true; 590 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 591 error_report("Invalid cache mode `%s'", optarg); 592 exit(EXIT_FAILURE); 593 } 594 break; 595 case QEMU_NBD_OPT_AIO: 596 if (seen_aio) { 597 error_report("--aio can only be specified once"); 598 exit(EXIT_FAILURE); 599 } 600 seen_aio = true; 601 if (!strcmp(optarg, "native")) { 602 flags |= BDRV_O_NATIVE_AIO; 603 } else if (!strcmp(optarg, "threads")) { 604 /* this is the default */ 605 } else { 606 error_report("invalid aio mode `%s'", optarg); 607 exit(EXIT_FAILURE); 608 } 609 break; 610 case QEMU_NBD_OPT_DISCARD: 611 if (seen_discard) { 612 error_report("--discard can only be specified once"); 613 exit(EXIT_FAILURE); 614 } 615 seen_discard = true; 616 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 617 error_report("Invalid discard mode `%s'", optarg); 618 exit(EXIT_FAILURE); 619 } 620 break; 621 case QEMU_NBD_OPT_DETECT_ZEROES: 622 detect_zeroes = 623 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 624 optarg, 625 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 626 &local_err); 627 if (local_err) { 628 error_reportf_err(local_err, 629 "Failed to parse detect_zeroes mode: "); 630 exit(EXIT_FAILURE); 631 } 632 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 633 !(flags & BDRV_O_UNMAP)) { 634 error_report("setting detect-zeroes to unmap is not allowed " 635 "without setting discard operation to unmap"); 636 exit(EXIT_FAILURE); 637 } 638 break; 639 case 'b': 640 bindto = optarg; 641 break; 642 case 'p': 643 port = optarg; 644 break; 645 case 'o': 646 dev_offset = strtoll (optarg, &end, 0); 647 if (*end) { 648 error_report("Invalid offset `%s'", optarg); 649 exit(EXIT_FAILURE); 650 } 651 if (dev_offset < 0) { 652 error_report("Offset must be positive `%s'", optarg); 653 exit(EXIT_FAILURE); 654 } 655 break; 656 case 'l': 657 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 658 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 659 optarg, false); 660 if (!sn_opts) { 661 error_report("Failed in parsing snapshot param `%s'", 662 optarg); 663 exit(EXIT_FAILURE); 664 } 665 } else { 666 sn_id_or_name = optarg; 667 } 668 /* fall through */ 669 case 'r': 670 nbdflags |= NBD_FLAG_READ_ONLY; 671 flags &= ~BDRV_O_RDWR; 672 break; 673 case 'P': 674 partition = strtol(optarg, &end, 0); 675 if (*end) { 676 error_report("Invalid partition `%s'", optarg); 677 exit(EXIT_FAILURE); 678 } 679 if (partition < 1 || partition > 8) { 680 error_report("Invalid partition %d", partition); 681 exit(EXIT_FAILURE); 682 } 683 break; 684 case 'k': 685 sockpath = optarg; 686 if (sockpath[0] != '/') { 687 error_report("socket path must be absolute"); 688 exit(EXIT_FAILURE); 689 } 690 break; 691 case 'd': 692 disconnect = true; 693 break; 694 case 'c': 695 device = optarg; 696 break; 697 case 'e': 698 shared = strtol(optarg, &end, 0); 699 if (*end) { 700 error_report("Invalid shared device number '%s'", optarg); 701 exit(EXIT_FAILURE); 702 } 703 if (shared < 1) { 704 error_report("Shared device number must be greater than 0"); 705 exit(EXIT_FAILURE); 706 } 707 break; 708 case 'f': 709 fmt = optarg; 710 break; 711 case 't': 712 persistent = 1; 713 break; 714 case 'x': 715 export_name = optarg; 716 break; 717 case 'D': 718 export_description = optarg; 719 break; 720 case 'v': 721 verbose = 1; 722 break; 723 case 'V': 724 version(argv[0]); 725 exit(0); 726 break; 727 case 'h': 728 usage(argv[0]); 729 exit(0); 730 break; 731 case '?': 732 error_report("Try `%s --help' for more information.", argv[0]); 733 exit(EXIT_FAILURE); 734 case QEMU_NBD_OPT_OBJECT: { 735 QemuOpts *opts; 736 opts = qemu_opts_parse_noisily(&qemu_object_opts, 737 optarg, true); 738 if (!opts) { 739 exit(EXIT_FAILURE); 740 } 741 } break; 742 case QEMU_NBD_OPT_TLSCREDS: 743 tlscredsid = optarg; 744 break; 745 case QEMU_NBD_OPT_IMAGE_OPTS: 746 imageOpts = true; 747 break; 748 case 'T': 749 g_free(trace_file); 750 trace_file = trace_opt_parse(optarg); 751 break; 752 case QEMU_NBD_OPT_FORK: 753 fork_process = true; 754 break; 755 } 756 } 757 758 if ((argc - optind) != 1) { 759 error_report("Invalid number of arguments"); 760 error_printf("Try `%s --help' for more information.\n", argv[0]); 761 exit(EXIT_FAILURE); 762 } 763 764 if (qemu_opts_foreach(&qemu_object_opts, 765 user_creatable_add_opts_foreach, 766 NULL, NULL)) { 767 exit(EXIT_FAILURE); 768 } 769 770 if (!trace_init_backends()) { 771 exit(1); 772 } 773 trace_init_file(trace_file); 774 qemu_set_log(LOG_TRACE); 775 776 socket_activation = check_socket_activation(); 777 if (socket_activation == 0) { 778 setup_address_and_port(&bindto, &port); 779 } else { 780 /* Using socket activation - check user didn't use -p etc. */ 781 const char *err_msg = socket_activation_validate_opts(device, sockpath, 782 bindto, port); 783 if (err_msg != NULL) { 784 error_report("%s", err_msg); 785 exit(EXIT_FAILURE); 786 } 787 788 /* qemu-nbd can only listen on a single socket. */ 789 if (socket_activation > 1) { 790 error_report("qemu-nbd does not support socket activation with %s > 1", 791 "LISTEN_FDS"); 792 exit(EXIT_FAILURE); 793 } 794 } 795 796 if (tlscredsid) { 797 if (sockpath) { 798 error_report("TLS is only supported with IPv4/IPv6"); 799 exit(EXIT_FAILURE); 800 } 801 if (device) { 802 error_report("TLS is not supported with a host device"); 803 exit(EXIT_FAILURE); 804 } 805 if (!export_name) { 806 /* Set the default NBD protocol export name, since 807 * we *must* use new style protocol for TLS */ 808 export_name = ""; 809 } 810 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 811 if (local_err) { 812 error_report("Failed to get TLS creds %s", 813 error_get_pretty(local_err)); 814 exit(EXIT_FAILURE); 815 } 816 } 817 818 if (disconnect) { 819 int nbdfd = open(argv[optind], O_RDWR); 820 if (nbdfd < 0) { 821 error_report("Cannot open %s: %s", argv[optind], 822 strerror(errno)); 823 exit(EXIT_FAILURE); 824 } 825 nbd_disconnect(nbdfd); 826 827 close(nbdfd); 828 829 printf("%s disconnected\n", argv[optind]); 830 831 return 0; 832 } 833 834 if ((device && !verbose) || fork_process) { 835 int stderr_fd[2]; 836 pid_t pid; 837 int ret; 838 839 if (qemu_pipe(stderr_fd) < 0) { 840 error_report("Error setting up communication pipe: %s", 841 strerror(errno)); 842 exit(EXIT_FAILURE); 843 } 844 845 /* Now daemonize, but keep a communication channel open to 846 * print errors and exit with the proper status code. 847 */ 848 pid = fork(); 849 if (pid < 0) { 850 error_report("Failed to fork: %s", strerror(errno)); 851 exit(EXIT_FAILURE); 852 } else if (pid == 0) { 853 close(stderr_fd[0]); 854 ret = qemu_daemon(1, 0); 855 856 /* Temporarily redirect stderr to the parent's pipe... */ 857 old_stderr = dup(STDERR_FILENO); 858 dup2(stderr_fd[1], STDERR_FILENO); 859 if (ret < 0) { 860 error_report("Failed to daemonize: %s", strerror(errno)); 861 exit(EXIT_FAILURE); 862 } 863 864 /* ... close the descriptor we inherited and go on. */ 865 close(stderr_fd[1]); 866 } else { 867 bool errors = false; 868 char *buf; 869 870 /* In the parent. Print error messages from the child until 871 * it closes the pipe. 872 */ 873 close(stderr_fd[1]); 874 buf = g_malloc(1024); 875 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 876 errors = true; 877 ret = qemu_write_full(STDERR_FILENO, buf, ret); 878 if (ret < 0) { 879 exit(EXIT_FAILURE); 880 } 881 } 882 if (ret < 0) { 883 error_report("Cannot read from daemon: %s", 884 strerror(errno)); 885 exit(EXIT_FAILURE); 886 } 887 888 /* Usually the daemon should not print any message. 889 * Exit with zero status in that case. 890 */ 891 exit(errors); 892 } 893 } 894 895 if (device != NULL && sockpath == NULL) { 896 sockpath = g_malloc(128); 897 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 898 } 899 900 server = qio_net_listener_new(); 901 if (socket_activation == 0) { 902 saddr = nbd_build_socket_address(sockpath, bindto, port); 903 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) { 904 object_unref(OBJECT(server)); 905 error_report_err(local_err); 906 exit(EXIT_FAILURE); 907 } 908 } else { 909 size_t i; 910 /* See comment in check_socket_activation above. */ 911 for (i = 0; i < socket_activation; i++) { 912 QIOChannelSocket *sioc; 913 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 914 &local_err); 915 if (sioc == NULL) { 916 object_unref(OBJECT(server)); 917 error_report("Failed to use socket activation: %s", 918 error_get_pretty(local_err)); 919 exit(EXIT_FAILURE); 920 } 921 qio_net_listener_add(server, sioc); 922 object_unref(OBJECT(sioc)); 923 } 924 } 925 926 if (qemu_init_main_loop(&local_err)) { 927 error_report_err(local_err); 928 exit(EXIT_FAILURE); 929 } 930 bdrv_init(); 931 atexit(bdrv_close_all); 932 933 srcpath = argv[optind]; 934 if (imageOpts) { 935 QemuOpts *opts; 936 if (fmt) { 937 error_report("--image-opts and -f are mutually exclusive"); 938 exit(EXIT_FAILURE); 939 } 940 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 941 if (!opts) { 942 qemu_opts_reset(&file_opts); 943 exit(EXIT_FAILURE); 944 } 945 options = qemu_opts_to_qdict(opts, NULL); 946 qemu_opts_reset(&file_opts); 947 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 948 } else { 949 if (fmt) { 950 options = qdict_new(); 951 qdict_put_str(options, "driver", fmt); 952 } 953 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 954 } 955 956 if (!blk) { 957 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 958 argv[optind]); 959 exit(EXIT_FAILURE); 960 } 961 bs = blk_bs(blk); 962 963 blk_set_enable_write_cache(blk, !writethrough); 964 965 if (sn_opts) { 966 ret = bdrv_snapshot_load_tmp(bs, 967 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 968 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 969 &local_err); 970 } else if (sn_id_or_name) { 971 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 972 &local_err); 973 } 974 if (ret < 0) { 975 error_reportf_err(local_err, "Failed to load snapshot: "); 976 exit(EXIT_FAILURE); 977 } 978 979 bs->detect_zeroes = detect_zeroes; 980 fd_size = blk_getlength(blk); 981 if (fd_size < 0) { 982 error_report("Failed to determine the image length: %s", 983 strerror(-fd_size)); 984 exit(EXIT_FAILURE); 985 } 986 987 if (dev_offset >= fd_size) { 988 error_report("Offset (%lld) has to be smaller than the image size " 989 "(%lld)", 990 (long long int)dev_offset, (long long int)fd_size); 991 exit(EXIT_FAILURE); 992 } 993 fd_size -= dev_offset; 994 995 if (partition != -1) { 996 ret = find_partition(blk, partition, &dev_offset, &fd_size); 997 if (ret < 0) { 998 error_report("Could not find partition %d: %s", partition, 999 strerror(-ret)); 1000 exit(EXIT_FAILURE); 1001 } 1002 } 1003 1004 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1005 writethrough, NULL, &local_err); 1006 if (!exp) { 1007 error_report_err(local_err); 1008 exit(EXIT_FAILURE); 1009 } 1010 if (export_name) { 1011 nbd_export_set_name(exp, export_name); 1012 nbd_export_set_description(exp, export_description); 1013 newproto = true; 1014 } else if (export_description) { 1015 error_report("Export description requires an export name"); 1016 exit(EXIT_FAILURE); 1017 } 1018 1019 if (device) { 1020 int ret; 1021 1022 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1023 if (ret != 0) { 1024 error_report("Failed to create client thread: %s", strerror(ret)); 1025 exit(EXIT_FAILURE); 1026 } 1027 } else { 1028 /* Shut up GCC warnings. */ 1029 memset(&client_thread, 0, sizeof(client_thread)); 1030 } 1031 1032 nbd_update_server_watch(); 1033 1034 /* now when the initialization is (almost) complete, chdir("/") 1035 * to free any busy filesystems */ 1036 if (chdir("/") < 0) { 1037 error_report("Could not chdir to root directory: %s", 1038 strerror(errno)); 1039 exit(EXIT_FAILURE); 1040 } 1041 1042 if (fork_process) { 1043 dup2(old_stderr, STDERR_FILENO); 1044 close(old_stderr); 1045 } 1046 1047 state = RUNNING; 1048 do { 1049 main_loop_wait(false); 1050 if (state == TERMINATE) { 1051 state = TERMINATING; 1052 nbd_export_close(exp); 1053 nbd_export_put(exp); 1054 exp = NULL; 1055 } 1056 } while (state != TERMINATED); 1057 1058 blk_unref(blk); 1059 if (sockpath) { 1060 unlink(sockpath); 1061 } 1062 1063 qemu_opts_del(sn_opts); 1064 1065 if (device) { 1066 void *ret; 1067 pthread_join(client_thread, &ret); 1068 exit(ret != NULL); 1069 } else { 1070 exit(EXIT_SUCCESS); 1071 } 1072 } 1073