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 <sys/types.h> 34 #include <sys/socket.h> 35 #include <netinet/in.h> 36 #include <netinet/tcp.h> 37 #include <arpa/inet.h> 38 #include <signal.h> 39 #include <libgen.h> 40 #include <pthread.h> 41 42 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 43 #define QEMU_NBD_OPT_CACHE 1 44 #define QEMU_NBD_OPT_AIO 2 45 #define QEMU_NBD_OPT_DISCARD 3 46 #define QEMU_NBD_OPT_DETECT_ZEROES 4 47 48 static NBDExport *exp; 49 static int verbose; 50 static char *srcpath; 51 static SocketAddress *saddr; 52 static int persistent = 0; 53 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 54 static int shared = 1; 55 static int nb_fds; 56 static int server_fd; 57 58 static void usage(const char *name) 59 { 60 (printf) ( 61 "Usage: %s [OPTIONS] FILE\n" 62 "QEMU Disk Network Block Device Server\n" 63 "\n" 64 " -h, --help display this help and exit\n" 65 " -V, --version output version information and exit\n" 66 "\n" 67 "Connection properties:\n" 68 " -p, --port=PORT port to listen on (default `%d')\n" 69 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 70 " -k, --socket=PATH path to the unix socket\n" 71 " (default '"SOCKET_PATH"')\n" 72 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 73 " -t, --persistent don't exit on the last connection\n" 74 " -v, --verbose display extra debugging information\n" 75 "\n" 76 "Exposing part of the image:\n" 77 " -o, --offset=OFFSET offset into the image\n" 78 " -P, --partition=NUM only expose partition NUM\n" 79 "\n" 80 #ifdef __linux__ 81 "Kernel NBD client support:\n" 82 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 83 " -d, --disconnect disconnect the specified device\n" 84 "\n" 85 #endif 86 "\n" 87 "Block device options:\n" 88 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 89 " -r, --read-only export read-only\n" 90 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 91 " file with backing_file=FILE, redirect the write to\n" 92 " the temporary one\n" 93 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 94 " load an internal snapshot inside FILE and export it\n" 95 " as an read-only device, SNAPSHOT_PARAM format is\n" 96 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 97 " '[ID_OR_NAME]'\n" 98 " -n, --nocache disable host cache\n" 99 " --cache=MODE set cache mode (none, writeback, ...)\n" 100 " --aio=MODE set AIO mode (native or threads)\n" 101 " --discard=MODE set discard mode (ignore, unmap)\n" 102 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 103 "\n" 104 "Report bugs to <qemu-devel@nongnu.org>\n" 105 , name, NBD_DEFAULT_PORT, "DEVICE"); 106 } 107 108 static void version(const char *name) 109 { 110 printf( 111 "%s version 0.0.1\n" 112 "Written by Anthony Liguori.\n" 113 "\n" 114 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n" 115 "This is free software; see the source for copying conditions. There is NO\n" 116 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 117 , name); 118 } 119 120 struct partition_record 121 { 122 uint8_t bootable; 123 uint8_t start_head; 124 uint32_t start_cylinder; 125 uint8_t start_sector; 126 uint8_t system; 127 uint8_t end_head; 128 uint8_t end_cylinder; 129 uint8_t end_sector; 130 uint32_t start_sector_abs; 131 uint32_t nb_sectors_abs; 132 }; 133 134 static void read_partition(uint8_t *p, struct partition_record *r) 135 { 136 r->bootable = p[0]; 137 r->start_head = p[1]; 138 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 139 r->start_sector = p[2] & 0x3f; 140 r->system = p[4]; 141 r->end_head = p[5]; 142 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 143 r->end_sector = p[6] & 0x3f; 144 145 r->start_sector_abs = le32_to_cpup((uint32_t *)(p + 8)); 146 r->nb_sectors_abs = le32_to_cpup((uint32_t *)(p + 12)); 147 } 148 149 static int find_partition(BlockBackend *blk, int partition, 150 off_t *offset, off_t *size) 151 { 152 struct partition_record mbr[4]; 153 uint8_t data[512]; 154 int i; 155 int ext_partnum = 4; 156 int ret; 157 158 if ((ret = blk_read(blk, 0, data, 1)) < 0) { 159 error_report("error while reading: %s", strerror(-ret)); 160 exit(EXIT_FAILURE); 161 } 162 163 if (data[510] != 0x55 || data[511] != 0xaa) { 164 return -EINVAL; 165 } 166 167 for (i = 0; i < 4; i++) { 168 read_partition(&data[446 + 16 * i], &mbr[i]); 169 170 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 171 continue; 172 } 173 174 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 175 struct partition_record ext[4]; 176 uint8_t data1[512]; 177 int j; 178 179 if ((ret = blk_read(blk, mbr[i].start_sector_abs, data1, 1)) < 0) { 180 error_report("error while reading: %s", strerror(-ret)); 181 exit(EXIT_FAILURE); 182 } 183 184 for (j = 0; j < 4; j++) { 185 read_partition(&data1[446 + 16 * j], &ext[j]); 186 if (!ext[j].system || !ext[j].nb_sectors_abs) { 187 continue; 188 } 189 190 if ((ext_partnum + j + 1) == partition) { 191 *offset = (uint64_t)ext[j].start_sector_abs << 9; 192 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 193 return 0; 194 } 195 } 196 ext_partnum += 4; 197 } else if ((i + 1) == partition) { 198 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 199 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 200 return 0; 201 } 202 } 203 204 return -ENOENT; 205 } 206 207 static void termsig_handler(int signum) 208 { 209 state = TERMINATE; 210 qemu_notify_event(); 211 } 212 213 214 static void *show_parts(void *arg) 215 { 216 char *device = arg; 217 int nbd; 218 219 /* linux just needs an open() to trigger 220 * the partition table update 221 * but remember to load the module with max_part != 0 : 222 * modprobe nbd max_part=63 223 */ 224 nbd = open(device, O_RDWR); 225 if (nbd >= 0) { 226 close(nbd); 227 } 228 return NULL; 229 } 230 231 static void *nbd_client_thread(void *arg) 232 { 233 char *device = arg; 234 off_t size; 235 uint32_t nbdflags; 236 int fd, sock; 237 int ret; 238 pthread_t show_parts_thread; 239 Error *local_error = NULL; 240 241 242 sock = socket_connect(saddr, &local_error, NULL, NULL); 243 if (sock < 0) { 244 error_report_err(local_error); 245 goto out; 246 } 247 248 ret = nbd_receive_negotiate(sock, NULL, &nbdflags, 249 &size, &local_error); 250 if (ret < 0) { 251 if (local_error) { 252 error_report_err(local_error); 253 } 254 goto out_socket; 255 } 256 257 fd = open(device, O_RDWR); 258 if (fd < 0) { 259 /* Linux-only, we can use %m in printf. */ 260 error_report("Failed to open %s: %m", device); 261 goto out_socket; 262 } 263 264 ret = nbd_init(fd, sock, nbdflags, size); 265 if (ret < 0) { 266 goto out_fd; 267 } 268 269 /* update partition table */ 270 pthread_create(&show_parts_thread, NULL, show_parts, device); 271 272 if (verbose) { 273 fprintf(stderr, "NBD device %s is now connected to %s\n", 274 device, srcpath); 275 } else { 276 /* Close stderr so that the qemu-nbd process exits. */ 277 dup2(STDOUT_FILENO, STDERR_FILENO); 278 } 279 280 ret = nbd_client(fd); 281 if (ret) { 282 goto out_fd; 283 } 284 close(fd); 285 kill(getpid(), SIGTERM); 286 return (void *) EXIT_SUCCESS; 287 288 out_fd: 289 close(fd); 290 out_socket: 291 closesocket(sock); 292 out: 293 kill(getpid(), SIGTERM); 294 return (void *) EXIT_FAILURE; 295 } 296 297 static int nbd_can_accept(void) 298 { 299 return nb_fds < shared; 300 } 301 302 static void nbd_export_closed(NBDExport *exp) 303 { 304 assert(state == TERMINATING); 305 state = TERMINATED; 306 } 307 308 static void nbd_update_server_fd_handler(int fd); 309 310 static void nbd_client_closed(NBDClient *client) 311 { 312 nb_fds--; 313 if (nb_fds == 0 && !persistent && state == RUNNING) { 314 state = TERMINATE; 315 } 316 nbd_update_server_fd_handler(server_fd); 317 nbd_client_put(client); 318 } 319 320 static void nbd_accept(void *opaque) 321 { 322 struct sockaddr_in addr; 323 socklen_t addr_len = sizeof(addr); 324 325 int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len); 326 if (fd < 0) { 327 perror("accept"); 328 return; 329 } 330 331 if (state >= TERMINATE) { 332 close(fd); 333 return; 334 } 335 336 if (nbd_client_new(exp, fd, nbd_client_closed)) { 337 nb_fds++; 338 nbd_update_server_fd_handler(server_fd); 339 } else { 340 shutdown(fd, 2); 341 close(fd); 342 } 343 } 344 345 static void nbd_update_server_fd_handler(int fd) 346 { 347 if (nbd_can_accept()) { 348 qemu_set_fd_handler(fd, nbd_accept, NULL, (void *)(uintptr_t)fd); 349 } else { 350 qemu_set_fd_handler(fd, NULL, NULL, NULL); 351 } 352 } 353 354 355 static SocketAddress *nbd_build_socket_address(const char *sockpath, 356 const char *bindto, 357 const char *port) 358 { 359 SocketAddress *saddr; 360 361 saddr = g_new0(SocketAddress, 1); 362 if (sockpath) { 363 saddr->type = SOCKET_ADDRESS_KIND_UNIX; 364 saddr->u.q_unix = g_new0(UnixSocketAddress, 1); 365 saddr->u.q_unix->path = g_strdup(sockpath); 366 } else { 367 saddr->type = SOCKET_ADDRESS_KIND_INET; 368 saddr->u.inet = g_new0(InetSocketAddress, 1); 369 saddr->u.inet->host = g_strdup(bindto); 370 if (port) { 371 saddr->u.inet->port = g_strdup(port); 372 } else { 373 saddr->u.inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 374 } 375 } 376 377 return saddr; 378 } 379 380 381 int main(int argc, char **argv) 382 { 383 BlockBackend *blk; 384 BlockDriverState *bs; 385 off_t dev_offset = 0; 386 uint32_t nbdflags = 0; 387 bool disconnect = false; 388 const char *bindto = "0.0.0.0"; 389 const char *port = NULL; 390 char *sockpath = NULL; 391 char *device = NULL; 392 off_t fd_size; 393 QemuOpts *sn_opts = NULL; 394 const char *sn_id_or_name = NULL; 395 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:"; 396 struct option lopt[] = { 397 { "help", 0, NULL, 'h' }, 398 { "version", 0, NULL, 'V' }, 399 { "bind", 1, NULL, 'b' }, 400 { "port", 1, NULL, 'p' }, 401 { "socket", 1, NULL, 'k' }, 402 { "offset", 1, NULL, 'o' }, 403 { "read-only", 0, NULL, 'r' }, 404 { "partition", 1, NULL, 'P' }, 405 { "connect", 1, NULL, 'c' }, 406 { "disconnect", 0, NULL, 'd' }, 407 { "snapshot", 0, NULL, 's' }, 408 { "load-snapshot", 1, NULL, 'l' }, 409 { "nocache", 0, NULL, 'n' }, 410 { "cache", 1, NULL, QEMU_NBD_OPT_CACHE }, 411 { "aio", 1, NULL, QEMU_NBD_OPT_AIO }, 412 { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD }, 413 { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES }, 414 { "shared", 1, NULL, 'e' }, 415 { "format", 1, NULL, 'f' }, 416 { "persistent", 0, NULL, 't' }, 417 { "verbose", 0, NULL, 'v' }, 418 { NULL, 0, NULL, 0 } 419 }; 420 int ch; 421 int opt_ind = 0; 422 char *end; 423 int flags = BDRV_O_RDWR; 424 int partition = -1; 425 int ret = 0; 426 int fd; 427 bool seen_cache = false; 428 bool seen_discard = false; 429 bool seen_aio = false; 430 pthread_t client_thread; 431 const char *fmt = NULL; 432 Error *local_err = NULL; 433 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 434 QDict *options = NULL; 435 436 /* The client thread uses SIGTERM to interrupt the server. A signal 437 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 438 */ 439 struct sigaction sa_sigterm; 440 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 441 sa_sigterm.sa_handler = termsig_handler; 442 sigaction(SIGTERM, &sa_sigterm, NULL); 443 qemu_init_exec_dir(argv[0]); 444 445 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 446 switch (ch) { 447 case 's': 448 flags |= BDRV_O_SNAPSHOT; 449 break; 450 case 'n': 451 optarg = (char *) "none"; 452 /* fallthrough */ 453 case QEMU_NBD_OPT_CACHE: 454 if (seen_cache) { 455 error_report("-n and --cache can only be specified once"); 456 exit(EXIT_FAILURE); 457 } 458 seen_cache = true; 459 if (bdrv_parse_cache_flags(optarg, &flags) == -1) { 460 error_report("Invalid cache mode `%s'", optarg); 461 exit(EXIT_FAILURE); 462 } 463 break; 464 case QEMU_NBD_OPT_AIO: 465 if (seen_aio) { 466 error_report("--aio can only be specified once"); 467 exit(EXIT_FAILURE); 468 } 469 seen_aio = true; 470 if (!strcmp(optarg, "native")) { 471 flags |= BDRV_O_NATIVE_AIO; 472 } else if (!strcmp(optarg, "threads")) { 473 /* this is the default */ 474 } else { 475 error_report("invalid aio mode `%s'", optarg); 476 exit(EXIT_FAILURE); 477 } 478 break; 479 case QEMU_NBD_OPT_DISCARD: 480 if (seen_discard) { 481 error_report("--discard can only be specified once"); 482 exit(EXIT_FAILURE); 483 } 484 seen_discard = true; 485 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 486 error_report("Invalid discard mode `%s'", optarg); 487 exit(EXIT_FAILURE); 488 } 489 break; 490 case QEMU_NBD_OPT_DETECT_ZEROES: 491 detect_zeroes = 492 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 493 optarg, 494 BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX, 495 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 496 &local_err); 497 if (local_err) { 498 error_reportf_err(local_err, 499 "Failed to parse detect_zeroes mode: "); 500 exit(EXIT_FAILURE); 501 } 502 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 503 !(flags & BDRV_O_UNMAP)) { 504 error_report("setting detect-zeroes to unmap is not allowed " 505 "without setting discard operation to unmap"); 506 exit(EXIT_FAILURE); 507 } 508 break; 509 case 'b': 510 bindto = optarg; 511 break; 512 case 'p': 513 port = optarg; 514 break; 515 case 'o': 516 dev_offset = strtoll (optarg, &end, 0); 517 if (*end) { 518 error_report("Invalid offset `%s'", optarg); 519 exit(EXIT_FAILURE); 520 } 521 if (dev_offset < 0) { 522 error_report("Offset must be positive `%s'", optarg); 523 exit(EXIT_FAILURE); 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 error_report("Failed in parsing snapshot param `%s'", 532 optarg); 533 exit(EXIT_FAILURE); 534 } 535 } else { 536 sn_id_or_name = optarg; 537 } 538 /* fall through */ 539 case 'r': 540 nbdflags |= NBD_FLAG_READ_ONLY; 541 flags &= ~BDRV_O_RDWR; 542 break; 543 case 'P': 544 partition = strtol(optarg, &end, 0); 545 if (*end) { 546 error_report("Invalid partition `%s'", optarg); 547 exit(EXIT_FAILURE); 548 } 549 if (partition < 1 || partition > 8) { 550 error_report("Invalid partition %d", partition); 551 exit(EXIT_FAILURE); 552 } 553 break; 554 case 'k': 555 sockpath = optarg; 556 if (sockpath[0] != '/') { 557 error_report("socket path must be absolute"); 558 exit(EXIT_FAILURE); 559 } 560 break; 561 case 'd': 562 disconnect = true; 563 break; 564 case 'c': 565 device = optarg; 566 break; 567 case 'e': 568 shared = strtol(optarg, &end, 0); 569 if (*end) { 570 error_report("Invalid shared device number '%s'", optarg); 571 exit(EXIT_FAILURE); 572 } 573 if (shared < 1) { 574 error_report("Shared device number must be greater than 0"); 575 exit(EXIT_FAILURE); 576 } 577 break; 578 case 'f': 579 fmt = optarg; 580 break; 581 case 't': 582 persistent = 1; 583 break; 584 case 'v': 585 verbose = 1; 586 break; 587 case 'V': 588 version(argv[0]); 589 exit(0); 590 break; 591 case 'h': 592 usage(argv[0]); 593 exit(0); 594 break; 595 case '?': 596 error_report("Try `%s --help' for more information.", argv[0]); 597 exit(EXIT_FAILURE); 598 } 599 } 600 601 if ((argc - optind) != 1) { 602 error_report("Invalid number of arguments"); 603 error_printf("Try `%s --help' for more information.\n", argv[0]); 604 exit(EXIT_FAILURE); 605 } 606 607 if (disconnect) { 608 fd = open(argv[optind], O_RDWR); 609 if (fd < 0) { 610 error_report("Cannot open %s: %s", argv[optind], 611 strerror(errno)); 612 exit(EXIT_FAILURE); 613 } 614 nbd_disconnect(fd); 615 616 close(fd); 617 618 printf("%s disconnected\n", argv[optind]); 619 620 return 0; 621 } 622 623 if (device && !verbose) { 624 int stderr_fd[2]; 625 pid_t pid; 626 int ret; 627 628 if (qemu_pipe(stderr_fd) < 0) { 629 error_report("Error setting up communication pipe: %s", 630 strerror(errno)); 631 exit(EXIT_FAILURE); 632 } 633 634 /* Now daemonize, but keep a communication channel open to 635 * print errors and exit with the proper status code. 636 */ 637 pid = fork(); 638 if (pid < 0) { 639 error_report("Failed to fork: %s", strerror(errno)); 640 exit(EXIT_FAILURE); 641 } else if (pid == 0) { 642 close(stderr_fd[0]); 643 ret = qemu_daemon(1, 0); 644 645 /* Temporarily redirect stderr to the parent's pipe... */ 646 dup2(stderr_fd[1], STDERR_FILENO); 647 if (ret < 0) { 648 error_report("Failed to daemonize: %s", strerror(errno)); 649 exit(EXIT_FAILURE); 650 } 651 652 /* ... close the descriptor we inherited and go on. */ 653 close(stderr_fd[1]); 654 } else { 655 bool errors = false; 656 char *buf; 657 658 /* In the parent. Print error messages from the child until 659 * it closes the pipe. 660 */ 661 close(stderr_fd[1]); 662 buf = g_malloc(1024); 663 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 664 errors = true; 665 ret = qemu_write_full(STDERR_FILENO, buf, ret); 666 if (ret < 0) { 667 exit(EXIT_FAILURE); 668 } 669 } 670 if (ret < 0) { 671 error_report("Cannot read from daemon: %s", 672 strerror(errno)); 673 exit(EXIT_FAILURE); 674 } 675 676 /* Usually the daemon should not print any message. 677 * Exit with zero status in that case. 678 */ 679 exit(errors); 680 } 681 } 682 683 if (device != NULL && sockpath == NULL) { 684 sockpath = g_malloc(128); 685 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 686 } 687 688 saddr = nbd_build_socket_address(sockpath, bindto, port); 689 690 if (qemu_init_main_loop(&local_err)) { 691 error_report_err(local_err); 692 exit(EXIT_FAILURE); 693 } 694 bdrv_init(); 695 atexit(bdrv_close_all); 696 697 if (fmt) { 698 options = qdict_new(); 699 qdict_put(options, "driver", qstring_from_str(fmt)); 700 } 701 702 srcpath = argv[optind]; 703 blk = blk_new_open("hda", srcpath, NULL, options, flags, &local_err); 704 if (!blk) { 705 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 706 argv[optind]); 707 exit(EXIT_FAILURE); 708 } 709 bs = blk_bs(blk); 710 711 if (sn_opts) { 712 ret = bdrv_snapshot_load_tmp(bs, 713 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 714 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 715 &local_err); 716 } else if (sn_id_or_name) { 717 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 718 &local_err); 719 } 720 if (ret < 0) { 721 error_reportf_err(local_err, "Failed to load snapshot: "); 722 exit(EXIT_FAILURE); 723 } 724 725 bs->detect_zeroes = detect_zeroes; 726 fd_size = blk_getlength(blk); 727 if (fd_size < 0) { 728 error_report("Failed to determine the image length: %s", 729 strerror(-fd_size)); 730 exit(EXIT_FAILURE); 731 } 732 733 if (partition != -1) { 734 ret = find_partition(blk, partition, &dev_offset, &fd_size); 735 if (ret < 0) { 736 error_report("Could not find partition %d: %s", partition, 737 strerror(-ret)); 738 exit(EXIT_FAILURE); 739 } 740 } 741 742 exp = nbd_export_new(blk, dev_offset, fd_size, nbdflags, nbd_export_closed, 743 &local_err); 744 if (!exp) { 745 error_report_err(local_err); 746 exit(EXIT_FAILURE); 747 } 748 749 fd = socket_listen(saddr, &local_err); 750 if (fd < 0) { 751 error_report_err(local_err); 752 return 1; 753 } 754 755 if (device) { 756 int ret; 757 758 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 759 if (ret != 0) { 760 error_report("Failed to create client thread: %s", strerror(ret)); 761 exit(EXIT_FAILURE); 762 } 763 } else { 764 /* Shut up GCC warnings. */ 765 memset(&client_thread, 0, sizeof(client_thread)); 766 } 767 768 server_fd = fd; 769 nbd_update_server_fd_handler(fd); 770 771 /* now when the initialization is (almost) complete, chdir("/") 772 * to free any busy filesystems */ 773 if (chdir("/") < 0) { 774 error_report("Could not chdir to root directory: %s", 775 strerror(errno)); 776 exit(EXIT_FAILURE); 777 } 778 779 state = RUNNING; 780 do { 781 main_loop_wait(false); 782 if (state == TERMINATE) { 783 state = TERMINATING; 784 nbd_export_close(exp); 785 nbd_export_put(exp); 786 exp = NULL; 787 } 788 } while (state != TERMINATED); 789 790 blk_unref(blk); 791 if (sockpath) { 792 unlink(sockpath); 793 } 794 795 qemu_opts_del(sn_opts); 796 797 if (device) { 798 void *ret; 799 pthread_join(client_thread, &ret); 800 exit(ret != NULL); 801 } else { 802 exit(EXIT_SUCCESS); 803 } 804 } 805