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-common.h" 20 #include "sysemu/block-backend.h" 21 #include "block/block_int.h" 22 #include "block/nbd.h" 23 #include "qemu/main-loop.h" 24 #include "qemu/sockets.h" 25 #include "qemu/error-report.h" 26 #include "block/snapshot.h" 27 #include "qapi/util.h" 28 #include "qapi/qmp/qstring.h" 29 30 #include <stdarg.h> 31 #include <stdio.h> 32 #include <getopt.h> 33 #include <err.h> 34 #include <sys/types.h> 35 #include <sys/socket.h> 36 #include <netinet/in.h> 37 #include <netinet/tcp.h> 38 #include <arpa/inet.h> 39 #include <signal.h> 40 #include <libgen.h> 41 #include <pthread.h> 42 43 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 44 #define QEMU_NBD_OPT_CACHE 1 45 #define QEMU_NBD_OPT_AIO 2 46 #define QEMU_NBD_OPT_DISCARD 3 47 #define QEMU_NBD_OPT_DETECT_ZEROES 4 48 49 static NBDExport *exp; 50 static int verbose; 51 static char *srcpath; 52 static SocketAddress *saddr; 53 static int persistent = 0; 54 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 55 static int shared = 1; 56 static int nb_fds; 57 static int server_fd; 58 59 static void usage(const char *name) 60 { 61 (printf) ( 62 "Usage: %s [OPTIONS] FILE\n" 63 "QEMU Disk Network Block Device Server\n" 64 "\n" 65 " -h, --help display this help and exit\n" 66 " -V, --version output version information and exit\n" 67 "\n" 68 "Connection properties:\n" 69 " -p, --port=PORT port to listen on (default `%d')\n" 70 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 71 " -k, --socket=PATH path to the unix socket\n" 72 " (default '"SOCKET_PATH"')\n" 73 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 74 " -t, --persistent don't exit on the last connection\n" 75 " -v, --verbose display extra debugging information\n" 76 "\n" 77 "Exposing part of the image:\n" 78 " -o, --offset=OFFSET offset into the image\n" 79 " -P, --partition=NUM only expose partition NUM\n" 80 "\n" 81 #ifdef __linux__ 82 "Kernel NBD client support:\n" 83 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 84 " -d, --disconnect disconnect the specified device\n" 85 "\n" 86 #endif 87 "\n" 88 "Block device options:\n" 89 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 90 " -r, --read-only export read-only\n" 91 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 92 " file with backing_file=FILE, redirect the write to\n" 93 " the temporary one\n" 94 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 95 " load an internal snapshot inside FILE and export it\n" 96 " as an read-only device, SNAPSHOT_PARAM format is\n" 97 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 98 " '[ID_OR_NAME]'\n" 99 " -n, --nocache disable host cache\n" 100 " --cache=MODE set cache mode (none, writeback, ...)\n" 101 #ifdef CONFIG_LINUX_AIO 102 " --aio=MODE set AIO mode (native or threads)\n" 103 #endif 104 " --discard=MODE set discard mode (ignore, unmap)\n" 105 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 106 "\n" 107 "Report bugs to <qemu-devel@nongnu.org>\n" 108 , name, NBD_DEFAULT_PORT, "DEVICE"); 109 } 110 111 static void version(const char *name) 112 { 113 printf( 114 "%s version 0.0.1\n" 115 "Written by Anthony Liguori.\n" 116 "\n" 117 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n" 118 "This is free software; see the source for copying conditions. There is NO\n" 119 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 120 , name); 121 } 122 123 struct partition_record 124 { 125 uint8_t bootable; 126 uint8_t start_head; 127 uint32_t start_cylinder; 128 uint8_t start_sector; 129 uint8_t system; 130 uint8_t end_head; 131 uint8_t end_cylinder; 132 uint8_t end_sector; 133 uint32_t start_sector_abs; 134 uint32_t nb_sectors_abs; 135 }; 136 137 static void read_partition(uint8_t *p, struct partition_record *r) 138 { 139 r->bootable = p[0]; 140 r->start_head = p[1]; 141 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 142 r->start_sector = p[2] & 0x3f; 143 r->system = p[4]; 144 r->end_head = p[5]; 145 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 146 r->end_sector = p[6] & 0x3f; 147 148 r->start_sector_abs = le32_to_cpup((uint32_t *)(p + 8)); 149 r->nb_sectors_abs = le32_to_cpup((uint32_t *)(p + 12)); 150 } 151 152 static int find_partition(BlockBackend *blk, int partition, 153 off_t *offset, off_t *size) 154 { 155 struct partition_record mbr[4]; 156 uint8_t data[512]; 157 int i; 158 int ext_partnum = 4; 159 int ret; 160 161 if ((ret = blk_read(blk, 0, data, 1)) < 0) { 162 errno = -ret; 163 err(EXIT_FAILURE, "error while reading"); 164 } 165 166 if (data[510] != 0x55 || data[511] != 0xaa) { 167 return -EINVAL; 168 } 169 170 for (i = 0; i < 4; i++) { 171 read_partition(&data[446 + 16 * i], &mbr[i]); 172 173 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 174 continue; 175 } 176 177 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 178 struct partition_record ext[4]; 179 uint8_t data1[512]; 180 int j; 181 182 if ((ret = blk_read(blk, mbr[i].start_sector_abs, data1, 1)) < 0) { 183 errno = -ret; 184 err(EXIT_FAILURE, "error while reading"); 185 } 186 187 for (j = 0; j < 4; j++) { 188 read_partition(&data1[446 + 16 * j], &ext[j]); 189 if (!ext[j].system || !ext[j].nb_sectors_abs) { 190 continue; 191 } 192 193 if ((ext_partnum + j + 1) == partition) { 194 *offset = (uint64_t)ext[j].start_sector_abs << 9; 195 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 196 return 0; 197 } 198 } 199 ext_partnum += 4; 200 } else if ((i + 1) == partition) { 201 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 202 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 203 return 0; 204 } 205 } 206 207 return -ENOENT; 208 } 209 210 static void termsig_handler(int signum) 211 { 212 state = TERMINATE; 213 qemu_notify_event(); 214 } 215 216 217 static void *show_parts(void *arg) 218 { 219 char *device = arg; 220 int nbd; 221 222 /* linux just needs an open() to trigger 223 * the partition table update 224 * but remember to load the module with max_part != 0 : 225 * modprobe nbd max_part=63 226 */ 227 nbd = open(device, O_RDWR); 228 if (nbd >= 0) { 229 close(nbd); 230 } 231 return NULL; 232 } 233 234 static void *nbd_client_thread(void *arg) 235 { 236 char *device = arg; 237 off_t size; 238 uint32_t nbdflags; 239 int fd, sock; 240 int ret; 241 pthread_t show_parts_thread; 242 Error *local_error = NULL; 243 244 245 sock = socket_connect(saddr, &local_error, NULL, NULL); 246 if (sock < 0) { 247 error_report_err(local_error); 248 goto out; 249 } 250 251 ret = nbd_receive_negotiate(sock, NULL, &nbdflags, 252 &size, &local_error); 253 if (ret < 0) { 254 if (local_error) { 255 fprintf(stderr, "%s\n", error_get_pretty(local_error)); 256 error_free(local_error); 257 } 258 goto out_socket; 259 } 260 261 fd = open(device, O_RDWR); 262 if (fd < 0) { 263 /* Linux-only, we can use %m in printf. */ 264 fprintf(stderr, "Failed to open %s: %m\n", device); 265 goto out_socket; 266 } 267 268 ret = nbd_init(fd, sock, nbdflags, size); 269 if (ret < 0) { 270 goto out_fd; 271 } 272 273 /* update partition table */ 274 pthread_create(&show_parts_thread, NULL, show_parts, device); 275 276 if (verbose) { 277 fprintf(stderr, "NBD device %s is now connected to %s\n", 278 device, srcpath); 279 } else { 280 /* Close stderr so that the qemu-nbd process exits. */ 281 dup2(STDOUT_FILENO, STDERR_FILENO); 282 } 283 284 ret = nbd_client(fd); 285 if (ret) { 286 goto out_fd; 287 } 288 close(fd); 289 kill(getpid(), SIGTERM); 290 return (void *) EXIT_SUCCESS; 291 292 out_fd: 293 close(fd); 294 out_socket: 295 closesocket(sock); 296 out: 297 kill(getpid(), SIGTERM); 298 return (void *) EXIT_FAILURE; 299 } 300 301 static int nbd_can_accept(void) 302 { 303 return nb_fds < shared; 304 } 305 306 static void nbd_export_closed(NBDExport *exp) 307 { 308 assert(state == TERMINATING); 309 state = TERMINATED; 310 } 311 312 static void nbd_update_server_fd_handler(int fd); 313 314 static void nbd_client_closed(NBDClient *client) 315 { 316 nb_fds--; 317 if (nb_fds == 0 && !persistent && state == RUNNING) { 318 state = TERMINATE; 319 } 320 nbd_update_server_fd_handler(server_fd); 321 nbd_client_put(client); 322 } 323 324 static void nbd_accept(void *opaque) 325 { 326 struct sockaddr_in addr; 327 socklen_t addr_len = sizeof(addr); 328 329 int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len); 330 if (fd < 0) { 331 perror("accept"); 332 return; 333 } 334 335 if (state >= TERMINATE) { 336 close(fd); 337 return; 338 } 339 340 if (nbd_client_new(exp, fd, nbd_client_closed)) { 341 nb_fds++; 342 nbd_update_server_fd_handler(server_fd); 343 } else { 344 shutdown(fd, 2); 345 close(fd); 346 } 347 } 348 349 static void nbd_update_server_fd_handler(int fd) 350 { 351 if (nbd_can_accept()) { 352 qemu_set_fd_handler(fd, nbd_accept, NULL, (void *)(uintptr_t)fd); 353 } else { 354 qemu_set_fd_handler(fd, NULL, NULL, NULL); 355 } 356 } 357 358 359 static SocketAddress *nbd_build_socket_address(const char *sockpath, 360 const char *bindto, 361 const char *port) 362 { 363 SocketAddress *saddr; 364 365 saddr = g_new0(SocketAddress, 1); 366 if (sockpath) { 367 saddr->kind = SOCKET_ADDRESS_KIND_UNIX; 368 saddr->q_unix = g_new0(UnixSocketAddress, 1); 369 saddr->q_unix->path = g_strdup(sockpath); 370 } else { 371 saddr->kind = SOCKET_ADDRESS_KIND_INET; 372 saddr->inet = g_new0(InetSocketAddress, 1); 373 saddr->inet->host = g_strdup(bindto); 374 if (port) { 375 saddr->inet->port = g_strdup(port); 376 } else { 377 saddr->inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 378 } 379 } 380 381 return saddr; 382 } 383 384 385 int main(int argc, char **argv) 386 { 387 BlockBackend *blk; 388 BlockDriverState *bs; 389 off_t dev_offset = 0; 390 uint32_t nbdflags = 0; 391 bool disconnect = false; 392 const char *bindto = "0.0.0.0"; 393 const char *port = NULL; 394 char *sockpath = NULL; 395 char *device = NULL; 396 off_t fd_size; 397 QemuOpts *sn_opts = NULL; 398 const char *sn_id_or_name = NULL; 399 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:"; 400 struct option lopt[] = { 401 { "help", 0, NULL, 'h' }, 402 { "version", 0, NULL, 'V' }, 403 { "bind", 1, NULL, 'b' }, 404 { "port", 1, NULL, 'p' }, 405 { "socket", 1, NULL, 'k' }, 406 { "offset", 1, NULL, 'o' }, 407 { "read-only", 0, NULL, 'r' }, 408 { "partition", 1, NULL, 'P' }, 409 { "connect", 1, NULL, 'c' }, 410 { "disconnect", 0, NULL, 'd' }, 411 { "snapshot", 0, NULL, 's' }, 412 { "load-snapshot", 1, NULL, 'l' }, 413 { "nocache", 0, NULL, 'n' }, 414 { "cache", 1, NULL, QEMU_NBD_OPT_CACHE }, 415 #ifdef CONFIG_LINUX_AIO 416 { "aio", 1, NULL, QEMU_NBD_OPT_AIO }, 417 #endif 418 { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD }, 419 { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES }, 420 { "shared", 1, NULL, 'e' }, 421 { "format", 1, NULL, 'f' }, 422 { "persistent", 0, NULL, 't' }, 423 { "verbose", 0, NULL, 'v' }, 424 { NULL, 0, NULL, 0 } 425 }; 426 int ch; 427 int opt_ind = 0; 428 char *end; 429 int flags = BDRV_O_RDWR; 430 int partition = -1; 431 int ret = 0; 432 int fd; 433 bool seen_cache = false; 434 bool seen_discard = false; 435 #ifdef CONFIG_LINUX_AIO 436 bool seen_aio = false; 437 #endif 438 pthread_t client_thread; 439 const char *fmt = NULL; 440 Error *local_err = NULL; 441 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 442 QDict *options = NULL; 443 444 /* The client thread uses SIGTERM to interrupt the server. A signal 445 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 446 */ 447 struct sigaction sa_sigterm; 448 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 449 sa_sigterm.sa_handler = termsig_handler; 450 sigaction(SIGTERM, &sa_sigterm, NULL); 451 qemu_init_exec_dir(argv[0]); 452 453 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 454 switch (ch) { 455 case 's': 456 flags |= BDRV_O_SNAPSHOT; 457 break; 458 case 'n': 459 optarg = (char *) "none"; 460 /* fallthrough */ 461 case QEMU_NBD_OPT_CACHE: 462 if (seen_cache) { 463 errx(EXIT_FAILURE, "-n and --cache can only be specified once"); 464 } 465 seen_cache = true; 466 if (bdrv_parse_cache_flags(optarg, &flags) == -1) { 467 errx(EXIT_FAILURE, "Invalid cache mode `%s'", optarg); 468 } 469 break; 470 #ifdef CONFIG_LINUX_AIO 471 case QEMU_NBD_OPT_AIO: 472 if (seen_aio) { 473 errx(EXIT_FAILURE, "--aio can only be specified once"); 474 } 475 seen_aio = true; 476 if (!strcmp(optarg, "native")) { 477 flags |= BDRV_O_NATIVE_AIO; 478 } else if (!strcmp(optarg, "threads")) { 479 /* this is the default */ 480 } else { 481 errx(EXIT_FAILURE, "invalid aio mode `%s'", optarg); 482 } 483 break; 484 #endif 485 case QEMU_NBD_OPT_DISCARD: 486 if (seen_discard) { 487 errx(EXIT_FAILURE, "--discard can only be specified once"); 488 } 489 seen_discard = true; 490 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 491 errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg); 492 } 493 break; 494 case QEMU_NBD_OPT_DETECT_ZEROES: 495 detect_zeroes = 496 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 497 optarg, 498 BLOCKDEV_DETECT_ZEROES_OPTIONS_MAX, 499 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 500 &local_err); 501 if (local_err) { 502 errx(EXIT_FAILURE, "Failed to parse detect_zeroes mode: %s", 503 error_get_pretty(local_err)); 504 } 505 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 506 !(flags & BDRV_O_UNMAP)) { 507 errx(EXIT_FAILURE, "setting detect-zeroes to unmap is not allowed " 508 "without setting discard operation to unmap"); 509 } 510 break; 511 case 'b': 512 bindto = optarg; 513 break; 514 case 'p': 515 port = optarg; 516 break; 517 case 'o': 518 dev_offset = strtoll (optarg, &end, 0); 519 if (*end) { 520 errx(EXIT_FAILURE, "Invalid offset `%s'", optarg); 521 } 522 if (dev_offset < 0) { 523 errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg); 524 } 525 break; 526 case 'l': 527 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 528 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 529 optarg, false); 530 if (!sn_opts) { 531 errx(EXIT_FAILURE, "Failed in parsing snapshot param `%s'", 532 optarg); 533 } 534 } else { 535 sn_id_or_name = optarg; 536 } 537 /* fall through */ 538 case 'r': 539 nbdflags |= NBD_FLAG_READ_ONLY; 540 flags &= ~BDRV_O_RDWR; 541 break; 542 case 'P': 543 partition = strtol(optarg, &end, 0); 544 if (*end) { 545 errx(EXIT_FAILURE, "Invalid partition `%s'", optarg); 546 } 547 if (partition < 1 || partition > 8) { 548 errx(EXIT_FAILURE, "Invalid partition %d", partition); 549 } 550 break; 551 case 'k': 552 sockpath = optarg; 553 if (sockpath[0] != '/') { 554 errx(EXIT_FAILURE, "socket path must be absolute\n"); 555 } 556 break; 557 case 'd': 558 disconnect = true; 559 break; 560 case 'c': 561 device = optarg; 562 break; 563 case 'e': 564 shared = strtol(optarg, &end, 0); 565 if (*end) { 566 errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg); 567 } 568 if (shared < 1) { 569 errx(EXIT_FAILURE, "Shared device number must be greater than 0\n"); 570 } 571 break; 572 case 'f': 573 fmt = optarg; 574 break; 575 case 't': 576 persistent = 1; 577 break; 578 case 'v': 579 verbose = 1; 580 break; 581 case 'V': 582 version(argv[0]); 583 exit(0); 584 break; 585 case 'h': 586 usage(argv[0]); 587 exit(0); 588 break; 589 case '?': 590 errx(EXIT_FAILURE, "Try `%s --help' for more information.", 591 argv[0]); 592 } 593 } 594 595 if ((argc - optind) != 1) { 596 errx(EXIT_FAILURE, "Invalid number of argument.\n" 597 "Try `%s --help' for more information.", 598 argv[0]); 599 } 600 601 if (disconnect) { 602 fd = open(argv[optind], O_RDWR); 603 if (fd < 0) { 604 err(EXIT_FAILURE, "Cannot open %s", argv[optind]); 605 } 606 nbd_disconnect(fd); 607 608 close(fd); 609 610 printf("%s disconnected\n", argv[optind]); 611 612 return 0; 613 } 614 615 if (device && !verbose) { 616 int stderr_fd[2]; 617 pid_t pid; 618 int ret; 619 620 if (qemu_pipe(stderr_fd) < 0) { 621 err(EXIT_FAILURE, "Error setting up communication pipe"); 622 } 623 624 /* Now daemonize, but keep a communication channel open to 625 * print errors and exit with the proper status code. 626 */ 627 pid = fork(); 628 if (pid < 0) { 629 err(EXIT_FAILURE, "Failed to fork"); 630 } else if (pid == 0) { 631 close(stderr_fd[0]); 632 ret = qemu_daemon(1, 0); 633 634 /* Temporarily redirect stderr to the parent's pipe... */ 635 dup2(stderr_fd[1], STDERR_FILENO); 636 if (ret < 0) { 637 err(EXIT_FAILURE, "Failed to daemonize"); 638 } 639 640 /* ... close the descriptor we inherited and go on. */ 641 close(stderr_fd[1]); 642 } else { 643 bool errors = false; 644 char *buf; 645 646 /* In the parent. Print error messages from the child until 647 * it closes the pipe. 648 */ 649 close(stderr_fd[1]); 650 buf = g_malloc(1024); 651 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 652 errors = true; 653 ret = qemu_write_full(STDERR_FILENO, buf, ret); 654 if (ret < 0) { 655 exit(EXIT_FAILURE); 656 } 657 } 658 if (ret < 0) { 659 err(EXIT_FAILURE, "Cannot read from daemon"); 660 } 661 662 /* Usually the daemon should not print any message. 663 * Exit with zero status in that case. 664 */ 665 exit(errors); 666 } 667 } 668 669 if (device != NULL && sockpath == NULL) { 670 sockpath = g_malloc(128); 671 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 672 } 673 674 saddr = nbd_build_socket_address(sockpath, bindto, port); 675 676 if (qemu_init_main_loop(&local_err)) { 677 error_report_err(local_err); 678 exit(EXIT_FAILURE); 679 } 680 bdrv_init(); 681 atexit(bdrv_close_all); 682 683 if (fmt) { 684 options = qdict_new(); 685 qdict_put(options, "driver", qstring_from_str(fmt)); 686 } 687 688 srcpath = argv[optind]; 689 blk = blk_new_open("hda", srcpath, NULL, options, flags, &local_err); 690 if (!blk) { 691 errx(EXIT_FAILURE, "Failed to blk_new_open '%s': %s", argv[optind], 692 error_get_pretty(local_err)); 693 } 694 bs = blk_bs(blk); 695 696 if (sn_opts) { 697 ret = bdrv_snapshot_load_tmp(bs, 698 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 699 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 700 &local_err); 701 } else if (sn_id_or_name) { 702 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 703 &local_err); 704 } 705 if (ret < 0) { 706 errno = -ret; 707 err(EXIT_FAILURE, 708 "Failed to load snapshot: %s", 709 error_get_pretty(local_err)); 710 } 711 712 bs->detect_zeroes = detect_zeroes; 713 fd_size = blk_getlength(blk); 714 if (fd_size < 0) { 715 errx(EXIT_FAILURE, "Failed to determine the image length: %s", 716 strerror(-fd_size)); 717 } 718 719 if (partition != -1) { 720 ret = find_partition(blk, partition, &dev_offset, &fd_size); 721 if (ret < 0) { 722 errno = -ret; 723 err(EXIT_FAILURE, "Could not find partition %d", partition); 724 } 725 } 726 727 exp = nbd_export_new(blk, dev_offset, fd_size, nbdflags, nbd_export_closed, 728 &local_err); 729 if (!exp) { 730 errx(EXIT_FAILURE, "%s", error_get_pretty(local_err)); 731 } 732 733 fd = socket_listen(saddr, &local_err); 734 if (fd < 0) { 735 error_report_err(local_err); 736 return 1; 737 } 738 739 if (device) { 740 int ret; 741 742 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 743 if (ret != 0) { 744 errx(EXIT_FAILURE, "Failed to create client thread: %s", 745 strerror(ret)); 746 } 747 } else { 748 /* Shut up GCC warnings. */ 749 memset(&client_thread, 0, sizeof(client_thread)); 750 } 751 752 server_fd = fd; 753 nbd_update_server_fd_handler(fd); 754 755 /* now when the initialization is (almost) complete, chdir("/") 756 * to free any busy filesystems */ 757 if (chdir("/") < 0) { 758 err(EXIT_FAILURE, "Could not chdir to root directory"); 759 } 760 761 state = RUNNING; 762 do { 763 main_loop_wait(false); 764 if (state == TERMINATE) { 765 state = TERMINATING; 766 nbd_export_close(exp); 767 nbd_export_put(exp); 768 exp = NULL; 769 } 770 } while (state != TERMINATED); 771 772 blk_unref(blk); 773 if (sockpath) { 774 unlink(sockpath); 775 } 776 777 qemu_opts_del(sn_opts); 778 779 if (device) { 780 void *ret; 781 pthread_join(client_thread, &ret); 782 exit(ret != NULL); 783 } else { 784 exit(EXIT_SUCCESS); 785 } 786 } 787