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 "block/block.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 29 #include <stdarg.h> 30 #include <stdio.h> 31 #include <getopt.h> 32 #include <err.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 char *sockpath; 52 static int persistent = 0; 53 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 54 static int shared = 1; 55 static int nb_fds; 56 57 static void usage(const char *name) 58 { 59 (printf) ( 60 "Usage: %s [OPTIONS] FILE\n" 61 "QEMU Disk Network Block Device Server\n" 62 "\n" 63 " -h, --help display this help and exit\n" 64 " -V, --version output version information and exit\n" 65 "\n" 66 "Connection properties:\n" 67 " -p, --port=PORT port to listen on (default `%d')\n" 68 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 69 " -k, --socket=PATH path to the unix socket\n" 70 " (default '"SOCKET_PATH"')\n" 71 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 72 " -t, --persistent don't exit on the last connection\n" 73 " -v, --verbose display extra debugging information\n" 74 "\n" 75 "Exposing part of the image:\n" 76 " -o, --offset=OFFSET offset into the image\n" 77 " -P, --partition=NUM only expose partition NUM\n" 78 "\n" 79 #ifdef __linux__ 80 "Kernel NBD client support:\n" 81 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 82 " -d, --disconnect disconnect the specified device\n" 83 "\n" 84 #endif 85 "\n" 86 "Block device options:\n" 87 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 88 " -r, --read-only export read-only\n" 89 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 90 " file with backing_file=FILE, redirect the write to\n" 91 " the temporary one\n" 92 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 93 " load an internal snapshot inside FILE and export it\n" 94 " as an read-only device, SNAPSHOT_PARAM format is\n" 95 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 96 " '[ID_OR_NAME]'\n" 97 " -n, --nocache disable host cache\n" 98 " --cache=MODE set cache mode (none, writeback, ...)\n" 99 #ifdef CONFIG_LINUX_AIO 100 " --aio=MODE set AIO mode (native or threads)\n" 101 #endif 102 " --discard=MODE set discard mode (ignore, unmap)\n" 103 " --detect-zeroes=MODE set detect-zeroes mode (off, on, discard)\n" 104 "\n" 105 "Report bugs to <qemu-devel@nongnu.org>\n" 106 , name, NBD_DEFAULT_PORT, "DEVICE"); 107 } 108 109 static void version(const char *name) 110 { 111 printf( 112 "%s version 0.0.1\n" 113 "Written by Anthony Liguori.\n" 114 "\n" 115 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n" 116 "This is free software; see the source for copying conditions. There is NO\n" 117 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 118 , name); 119 } 120 121 struct partition_record 122 { 123 uint8_t bootable; 124 uint8_t start_head; 125 uint32_t start_cylinder; 126 uint8_t start_sector; 127 uint8_t system; 128 uint8_t end_head; 129 uint8_t end_cylinder; 130 uint8_t end_sector; 131 uint32_t start_sector_abs; 132 uint32_t nb_sectors_abs; 133 }; 134 135 static void read_partition(uint8_t *p, struct partition_record *r) 136 { 137 r->bootable = p[0]; 138 r->start_head = p[1]; 139 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 140 r->start_sector = p[2] & 0x3f; 141 r->system = p[4]; 142 r->end_head = p[5]; 143 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 144 r->end_sector = p[6] & 0x3f; 145 r->start_sector_abs = p[8] | p[9] << 8 | p[10] << 16 | p[11] << 24; 146 r->nb_sectors_abs = p[12] | p[13] << 8 | p[14] << 16 | p[15] << 24; 147 } 148 149 static int find_partition(BlockDriverState *bs, 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 = bdrv_read(bs, 0, data, 1)) < 0) { 159 errno = -ret; 160 err(EXIT_FAILURE, "error while reading"); 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].nb_sectors_abs) 171 continue; 172 173 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 174 struct partition_record ext[4]; 175 uint8_t data1[512]; 176 int j; 177 178 if ((ret = bdrv_read(bs, mbr[i].start_sector_abs, data1, 1)) < 0) { 179 errno = -ret; 180 err(EXIT_FAILURE, "error while reading"); 181 } 182 183 for (j = 0; j < 4; j++) { 184 read_partition(&data1[446 + 16 * j], &ext[j]); 185 if (!ext[j].nb_sectors_abs) 186 continue; 187 188 if ((ext_partnum + j + 1) == partition) { 189 *offset = (uint64_t)ext[j].start_sector_abs << 9; 190 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 191 return 0; 192 } 193 } 194 ext_partnum += 4; 195 } else if ((i + 1) == partition) { 196 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 197 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 198 return 0; 199 } 200 } 201 202 return -ENOENT; 203 } 204 205 static void termsig_handler(int signum) 206 { 207 state = TERMINATE; 208 qemu_notify_event(); 209 } 210 211 static void combine_addr(char *buf, size_t len, const char* address, 212 uint16_t port) 213 { 214 /* If the address-part contains a colon, it's an IPv6 IP so needs [] */ 215 if (strstr(address, ":")) { 216 snprintf(buf, len, "[%s]:%u", address, port); 217 } else { 218 snprintf(buf, len, "%s:%u", address, port); 219 } 220 } 221 222 static int tcp_socket_incoming(const char *address, uint16_t port) 223 { 224 char address_and_port[128]; 225 Error *local_err = NULL; 226 227 combine_addr(address_and_port, 128, address, port); 228 int fd = inet_listen(address_and_port, NULL, 0, SOCK_STREAM, 0, &local_err); 229 230 if (local_err != NULL) { 231 error_report("%s", error_get_pretty(local_err)); 232 error_free(local_err); 233 } 234 return fd; 235 } 236 237 static int unix_socket_incoming(const char *path) 238 { 239 Error *local_err = NULL; 240 int fd = unix_listen(path, NULL, 0, &local_err); 241 242 if (local_err != NULL) { 243 error_report("%s", error_get_pretty(local_err)); 244 error_free(local_err); 245 } 246 return fd; 247 } 248 249 static int unix_socket_outgoing(const char *path) 250 { 251 Error *local_err = NULL; 252 int fd = unix_connect(path, &local_err); 253 254 if (local_err != NULL) { 255 error_report("%s", error_get_pretty(local_err)); 256 error_free(local_err); 257 } 258 return fd; 259 } 260 261 static void *show_parts(void *arg) 262 { 263 char *device = arg; 264 int nbd; 265 266 /* linux just needs an open() to trigger 267 * the partition table update 268 * but remember to load the module with max_part != 0 : 269 * modprobe nbd max_part=63 270 */ 271 nbd = open(device, O_RDWR); 272 if (nbd >= 0) { 273 close(nbd); 274 } 275 return NULL; 276 } 277 278 static void *nbd_client_thread(void *arg) 279 { 280 char *device = arg; 281 off_t size; 282 size_t blocksize; 283 uint32_t nbdflags; 284 int fd, sock; 285 int ret; 286 pthread_t show_parts_thread; 287 288 sock = unix_socket_outgoing(sockpath); 289 if (sock < 0) { 290 goto out; 291 } 292 293 ret = nbd_receive_negotiate(sock, NULL, &nbdflags, 294 &size, &blocksize); 295 if (ret < 0) { 296 goto out_socket; 297 } 298 299 fd = open(device, O_RDWR); 300 if (fd < 0) { 301 /* Linux-only, we can use %m in printf. */ 302 fprintf(stderr, "Failed to open %s: %m\n", device); 303 goto out_socket; 304 } 305 306 ret = nbd_init(fd, sock, nbdflags, size, blocksize); 307 if (ret < 0) { 308 goto out_fd; 309 } 310 311 /* update partition table */ 312 pthread_create(&show_parts_thread, NULL, show_parts, device); 313 314 if (verbose) { 315 fprintf(stderr, "NBD device %s is now connected to %s\n", 316 device, srcpath); 317 } else { 318 /* Close stderr so that the qemu-nbd process exits. */ 319 dup2(STDOUT_FILENO, STDERR_FILENO); 320 } 321 322 ret = nbd_client(fd); 323 if (ret) { 324 goto out_fd; 325 } 326 close(fd); 327 kill(getpid(), SIGTERM); 328 return (void *) EXIT_SUCCESS; 329 330 out_fd: 331 close(fd); 332 out_socket: 333 closesocket(sock); 334 out: 335 kill(getpid(), SIGTERM); 336 return (void *) EXIT_FAILURE; 337 } 338 339 static int nbd_can_accept(void *opaque) 340 { 341 return nb_fds < shared; 342 } 343 344 static void nbd_export_closed(NBDExport *exp) 345 { 346 assert(state == TERMINATING); 347 state = TERMINATED; 348 } 349 350 static void nbd_client_closed(NBDClient *client) 351 { 352 nb_fds--; 353 if (nb_fds == 0 && !persistent && state == RUNNING) { 354 state = TERMINATE; 355 } 356 qemu_notify_event(); 357 nbd_client_put(client); 358 } 359 360 static void nbd_accept(void *opaque) 361 { 362 int server_fd = (uintptr_t) opaque; 363 struct sockaddr_in addr; 364 socklen_t addr_len = sizeof(addr); 365 366 int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len); 367 if (fd < 0) { 368 perror("accept"); 369 return; 370 } 371 372 if (state >= TERMINATE) { 373 close(fd); 374 return; 375 } 376 377 if (nbd_client_new(exp, fd, nbd_client_closed)) { 378 nb_fds++; 379 } else { 380 shutdown(fd, 2); 381 close(fd); 382 } 383 } 384 385 int main(int argc, char **argv) 386 { 387 BlockDriverState *bs; 388 BlockDriver *drv; 389 off_t dev_offset = 0; 390 uint32_t nbdflags = 0; 391 bool disconnect = false; 392 const char *bindto = "0.0.0.0"; 393 char *device = NULL; 394 int port = NBD_DEFAULT_PORT; 395 off_t fd_size; 396 QemuOpts *sn_opts = NULL; 397 const char *sn_id_or_name = NULL; 398 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:"; 399 struct option lopt[] = { 400 { "help", 0, NULL, 'h' }, 401 { "version", 0, NULL, 'V' }, 402 { "bind", 1, NULL, 'b' }, 403 { "port", 1, NULL, 'p' }, 404 { "socket", 1, NULL, 'k' }, 405 { "offset", 1, NULL, 'o' }, 406 { "read-only", 0, NULL, 'r' }, 407 { "partition", 1, NULL, 'P' }, 408 { "connect", 1, NULL, 'c' }, 409 { "disconnect", 0, NULL, 'd' }, 410 { "snapshot", 0, NULL, 's' }, 411 { "load-snapshot", 1, NULL, 'l' }, 412 { "nocache", 0, NULL, 'n' }, 413 { "cache", 1, NULL, QEMU_NBD_OPT_CACHE }, 414 #ifdef CONFIG_LINUX_AIO 415 { "aio", 1, NULL, QEMU_NBD_OPT_AIO }, 416 #endif 417 { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD }, 418 { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES }, 419 { "shared", 1, NULL, 'e' }, 420 { "format", 1, NULL, 'f' }, 421 { "persistent", 0, NULL, 't' }, 422 { "verbose", 0, NULL, 'v' }, 423 { NULL, 0, NULL, 0 } 424 }; 425 int ch; 426 int opt_ind = 0; 427 int li; 428 char *end; 429 int flags = BDRV_O_RDWR; 430 int partition = -1; 431 int ret; 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; 442 443 /* The client thread uses SIGTERM to interrupt the server. A signal 444 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 445 */ 446 struct sigaction sa_sigterm; 447 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 448 sa_sigterm.sa_handler = termsig_handler; 449 sigaction(SIGTERM, &sa_sigterm, NULL); 450 qemu_init_exec_dir(argv[0]); 451 452 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 453 switch (ch) { 454 case 's': 455 flags |= BDRV_O_SNAPSHOT; 456 break; 457 case 'n': 458 optarg = (char *) "none"; 459 /* fallthrough */ 460 case QEMU_NBD_OPT_CACHE: 461 if (seen_cache) { 462 errx(EXIT_FAILURE, "-n and --cache can only be specified once"); 463 } 464 seen_cache = true; 465 if (bdrv_parse_cache_flags(optarg, &flags) == -1) { 466 errx(EXIT_FAILURE, "Invalid cache mode `%s'", optarg); 467 } 468 break; 469 #ifdef CONFIG_LINUX_AIO 470 case QEMU_NBD_OPT_AIO: 471 if (seen_aio) { 472 errx(EXIT_FAILURE, "--aio can only be specified once"); 473 } 474 seen_aio = true; 475 if (!strcmp(optarg, "native")) { 476 flags |= BDRV_O_NATIVE_AIO; 477 } else if (!strcmp(optarg, "threads")) { 478 /* this is the default */ 479 } else { 480 errx(EXIT_FAILURE, "invalid aio mode `%s'", optarg); 481 } 482 break; 483 #endif 484 case QEMU_NBD_OPT_DISCARD: 485 if (seen_discard) { 486 errx(EXIT_FAILURE, "--discard can only be specified once"); 487 } 488 seen_discard = true; 489 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 490 errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg); 491 } 492 break; 493 case QEMU_NBD_OPT_DETECT_ZEROES: 494 detect_zeroes = 495 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 496 optarg, 497 BLOCKDEV_DETECT_ZEROES_OPTIONS_MAX, 498 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 499 &local_err); 500 if (local_err) { 501 errx(EXIT_FAILURE, "Failed to parse detect_zeroes mode: %s", 502 error_get_pretty(local_err)); 503 } 504 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 505 !(flags & BDRV_O_UNMAP)) { 506 errx(EXIT_FAILURE, "setting detect-zeroes to unmap is not allowed " 507 "without setting discard operation to unmap"); 508 } 509 break; 510 case 'b': 511 bindto = optarg; 512 break; 513 case 'p': 514 li = strtol(optarg, &end, 0); 515 if (*end) { 516 errx(EXIT_FAILURE, "Invalid port `%s'", optarg); 517 } 518 if (li < 1 || li > 65535) { 519 errx(EXIT_FAILURE, "Port out of range `%s'", optarg); 520 } 521 port = (uint16_t)li; 522 break; 523 case 'o': 524 dev_offset = strtoll (optarg, &end, 0); 525 if (*end) { 526 errx(EXIT_FAILURE, "Invalid offset `%s'", optarg); 527 } 528 if (dev_offset < 0) { 529 errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg); 530 } 531 break; 532 case 'l': 533 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 534 sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0); 535 if (!sn_opts) { 536 errx(EXIT_FAILURE, "Failed in parsing snapshot param `%s'", 537 optarg); 538 } 539 } else { 540 sn_id_or_name = optarg; 541 } 542 /* fall through */ 543 case 'r': 544 nbdflags |= NBD_FLAG_READ_ONLY; 545 flags &= ~BDRV_O_RDWR; 546 break; 547 case 'P': 548 partition = strtol(optarg, &end, 0); 549 if (*end) { 550 errx(EXIT_FAILURE, "Invalid partition `%s'", optarg); 551 } 552 if (partition < 1 || partition > 8) { 553 errx(EXIT_FAILURE, "Invalid partition %d", partition); 554 } 555 break; 556 case 'k': 557 sockpath = optarg; 558 if (sockpath[0] != '/') { 559 errx(EXIT_FAILURE, "socket path must be absolute\n"); 560 } 561 break; 562 case 'd': 563 disconnect = true; 564 break; 565 case 'c': 566 device = optarg; 567 break; 568 case 'e': 569 shared = strtol(optarg, &end, 0); 570 if (*end) { 571 errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg); 572 } 573 if (shared < 1) { 574 errx(EXIT_FAILURE, "Shared device number must be greater than 0\n"); 575 } 576 break; 577 case 'f': 578 fmt = optarg; 579 break; 580 case 't': 581 persistent = 1; 582 break; 583 case 'v': 584 verbose = 1; 585 break; 586 case 'V': 587 version(argv[0]); 588 exit(0); 589 break; 590 case 'h': 591 usage(argv[0]); 592 exit(0); 593 break; 594 case '?': 595 errx(EXIT_FAILURE, "Try `%s --help' for more information.", 596 argv[0]); 597 } 598 } 599 600 if ((argc - optind) != 1) { 601 errx(EXIT_FAILURE, "Invalid number of argument.\n" 602 "Try `%s --help' for more information.", 603 argv[0]); 604 } 605 606 if (disconnect) { 607 fd = open(argv[optind], O_RDWR); 608 if (fd < 0) { 609 err(EXIT_FAILURE, "Cannot open %s", argv[optind]); 610 } 611 nbd_disconnect(fd); 612 613 close(fd); 614 615 printf("%s disconnected\n", argv[optind]); 616 617 return 0; 618 } 619 620 if (device && !verbose) { 621 int stderr_fd[2]; 622 pid_t pid; 623 int ret; 624 625 if (qemu_pipe(stderr_fd) < 0) { 626 err(EXIT_FAILURE, "Error setting up communication pipe"); 627 } 628 629 /* Now daemonize, but keep a communication channel open to 630 * print errors and exit with the proper status code. 631 */ 632 pid = fork(); 633 if (pid == 0) { 634 close(stderr_fd[0]); 635 ret = qemu_daemon(1, 0); 636 637 /* Temporarily redirect stderr to the parent's pipe... */ 638 dup2(stderr_fd[1], STDERR_FILENO); 639 if (ret < 0) { 640 err(EXIT_FAILURE, "Failed to daemonize"); 641 } 642 643 /* ... close the descriptor we inherited and go on. */ 644 close(stderr_fd[1]); 645 } else { 646 bool errors = false; 647 char *buf; 648 649 /* In the parent. Print error messages from the child until 650 * it closes the pipe. 651 */ 652 close(stderr_fd[1]); 653 buf = g_malloc(1024); 654 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 655 errors = true; 656 ret = qemu_write_full(STDERR_FILENO, buf, ret); 657 if (ret < 0) { 658 exit(EXIT_FAILURE); 659 } 660 } 661 if (ret < 0) { 662 err(EXIT_FAILURE, "Cannot read from daemon"); 663 } 664 665 /* Usually the daemon should not print any message. 666 * Exit with zero status in that case. 667 */ 668 exit(errors); 669 } 670 } 671 672 if (device != NULL && sockpath == NULL) { 673 sockpath = g_malloc(128); 674 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 675 } 676 677 if (qemu_init_main_loop(&local_err)) { 678 error_report("%s", error_get_pretty(local_err)); 679 error_free(local_err); 680 exit(EXIT_FAILURE); 681 } 682 bdrv_init(); 683 atexit(bdrv_close_all); 684 685 if (fmt) { 686 drv = bdrv_find_format(fmt); 687 if (!drv) { 688 errx(EXIT_FAILURE, "Unknown file format '%s'", fmt); 689 } 690 } else { 691 drv = NULL; 692 } 693 694 bs = bdrv_new("hda", &error_abort); 695 696 srcpath = argv[optind]; 697 ret = bdrv_open(&bs, srcpath, NULL, NULL, flags, drv, &local_err); 698 if (ret < 0) { 699 errno = -ret; 700 err(EXIT_FAILURE, "Failed to bdrv_open '%s': %s", argv[optind], 701 error_get_pretty(local_err)); 702 } 703 704 if (sn_opts) { 705 ret = bdrv_snapshot_load_tmp(bs, 706 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 707 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 708 &local_err); 709 } else if (sn_id_or_name) { 710 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 711 &local_err); 712 } 713 if (ret < 0) { 714 errno = -ret; 715 err(EXIT_FAILURE, 716 "Failed to load snapshot: %s", 717 error_get_pretty(local_err)); 718 } 719 720 bs->detect_zeroes = detect_zeroes; 721 fd_size = bdrv_getlength(bs); 722 723 if (partition != -1) { 724 ret = find_partition(bs, partition, &dev_offset, &fd_size); 725 if (ret < 0) { 726 errno = -ret; 727 err(EXIT_FAILURE, "Could not find partition %d", partition); 728 } 729 } 730 731 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed); 732 733 if (sockpath) { 734 fd = unix_socket_incoming(sockpath); 735 } else { 736 fd = tcp_socket_incoming(bindto, port); 737 } 738 739 if (fd < 0) { 740 return 1; 741 } 742 743 if (device) { 744 int ret; 745 746 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 747 if (ret != 0) { 748 errx(EXIT_FAILURE, "Failed to create client thread: %s", 749 strerror(ret)); 750 } 751 } else { 752 /* Shut up GCC warnings. */ 753 memset(&client_thread, 0, sizeof(client_thread)); 754 } 755 756 qemu_set_fd_handler2(fd, nbd_can_accept, nbd_accept, NULL, 757 (void *)(uintptr_t)fd); 758 759 /* now when the initialization is (almost) complete, chdir("/") 760 * to free any busy filesystems */ 761 if (chdir("/") < 0) { 762 err(EXIT_FAILURE, "Could not chdir to root directory"); 763 } 764 765 state = RUNNING; 766 do { 767 main_loop_wait(false); 768 if (state == TERMINATE) { 769 state = TERMINATING; 770 nbd_export_close(exp); 771 nbd_export_put(exp); 772 exp = NULL; 773 } 774 } while (state != TERMINATED); 775 776 bdrv_close(bs); 777 if (sockpath) { 778 unlink(sockpath); 779 } 780 781 if (sn_opts) { 782 qemu_opts_del(sn_opts); 783 } 784 785 if (device) { 786 void *ret; 787 pthread_join(client_thread, &ret); 788 exit(ret != NULL); 789 } else { 790 exit(EXIT_SUCCESS); 791 } 792 } 793