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