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 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(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 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 = blk_read(blk, 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_err(local_err); 232 } 233 return fd; 234 } 235 236 static int unix_socket_incoming(const char *path) 237 { 238 Error *local_err = NULL; 239 int fd = unix_listen(path, NULL, 0, &local_err); 240 241 if (local_err != NULL) { 242 error_report_err(local_err); 243 } 244 return fd; 245 } 246 247 static int unix_socket_outgoing(const char *path) 248 { 249 Error *local_err = NULL; 250 int fd = unix_connect(path, &local_err); 251 252 if (local_err != NULL) { 253 error_report_err(local_err); 254 } 255 return fd; 256 } 257 258 static void *show_parts(void *arg) 259 { 260 char *device = arg; 261 int nbd; 262 263 /* linux just needs an open() to trigger 264 * the partition table update 265 * but remember to load the module with max_part != 0 : 266 * modprobe nbd max_part=63 267 */ 268 nbd = open(device, O_RDWR); 269 if (nbd >= 0) { 270 close(nbd); 271 } 272 return NULL; 273 } 274 275 static void *nbd_client_thread(void *arg) 276 { 277 char *device = arg; 278 off_t size; 279 size_t blocksize; 280 uint32_t nbdflags; 281 int fd, sock; 282 int ret; 283 pthread_t show_parts_thread; 284 Error *local_error = NULL; 285 286 sock = unix_socket_outgoing(sockpath); 287 if (sock < 0) { 288 goto out; 289 } 290 291 ret = nbd_receive_negotiate(sock, NULL, &nbdflags, 292 &size, &blocksize, &local_error); 293 if (ret < 0) { 294 if (local_error) { 295 fprintf(stderr, "%s\n", error_get_pretty(local_error)); 296 error_free(local_error); 297 } 298 goto out_socket; 299 } 300 301 fd = open(device, O_RDWR); 302 if (fd < 0) { 303 /* Linux-only, we can use %m in printf. */ 304 fprintf(stderr, "Failed to open %s: %m\n", device); 305 goto out_socket; 306 } 307 308 ret = nbd_init(fd, sock, nbdflags, size, blocksize); 309 if (ret < 0) { 310 goto out_fd; 311 } 312 313 /* update partition table */ 314 pthread_create(&show_parts_thread, NULL, show_parts, device); 315 316 if (verbose) { 317 fprintf(stderr, "NBD device %s is now connected to %s\n", 318 device, srcpath); 319 } else { 320 /* Close stderr so that the qemu-nbd process exits. */ 321 dup2(STDOUT_FILENO, STDERR_FILENO); 322 } 323 324 ret = nbd_client(fd); 325 if (ret) { 326 goto out_fd; 327 } 328 close(fd); 329 kill(getpid(), SIGTERM); 330 return (void *) EXIT_SUCCESS; 331 332 out_fd: 333 close(fd); 334 out_socket: 335 closesocket(sock); 336 out: 337 kill(getpid(), SIGTERM); 338 return (void *) EXIT_FAILURE; 339 } 340 341 static int nbd_can_accept(void *opaque) 342 { 343 return nb_fds < shared; 344 } 345 346 static void nbd_export_closed(NBDExport *exp) 347 { 348 assert(state == TERMINATING); 349 state = TERMINATED; 350 } 351 352 static void nbd_client_closed(NBDClient *client) 353 { 354 nb_fds--; 355 if (nb_fds == 0 && !persistent && state == RUNNING) { 356 state = TERMINATE; 357 } 358 qemu_notify_event(); 359 nbd_client_put(client); 360 } 361 362 static void nbd_accept(void *opaque) 363 { 364 int server_fd = (uintptr_t) opaque; 365 struct sockaddr_in addr; 366 socklen_t addr_len = sizeof(addr); 367 368 int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len); 369 if (fd < 0) { 370 perror("accept"); 371 return; 372 } 373 374 if (state >= TERMINATE) { 375 close(fd); 376 return; 377 } 378 379 if (nbd_client_new(exp, fd, nbd_client_closed)) { 380 nb_fds++; 381 } else { 382 shutdown(fd, 2); 383 close(fd); 384 } 385 } 386 387 int main(int argc, char **argv) 388 { 389 BlockBackend *blk; 390 BlockDriverState *bs; 391 off_t dev_offset = 0; 392 uint32_t nbdflags = 0; 393 bool disconnect = false; 394 const char *bindto = "0.0.0.0"; 395 char *device = NULL; 396 int port = NBD_DEFAULT_PORT; 397 off_t fd_size; 398 QemuOpts *sn_opts = NULL; 399 const char *sn_id_or_name = NULL; 400 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:"; 401 struct option lopt[] = { 402 { "help", 0, NULL, 'h' }, 403 { "version", 0, NULL, 'V' }, 404 { "bind", 1, NULL, 'b' }, 405 { "port", 1, NULL, 'p' }, 406 { "socket", 1, NULL, 'k' }, 407 { "offset", 1, NULL, 'o' }, 408 { "read-only", 0, NULL, 'r' }, 409 { "partition", 1, NULL, 'P' }, 410 { "connect", 1, NULL, 'c' }, 411 { "disconnect", 0, NULL, 'd' }, 412 { "snapshot", 0, NULL, 's' }, 413 { "load-snapshot", 1, NULL, 'l' }, 414 { "nocache", 0, NULL, 'n' }, 415 { "cache", 1, NULL, QEMU_NBD_OPT_CACHE }, 416 #ifdef CONFIG_LINUX_AIO 417 { "aio", 1, NULL, QEMU_NBD_OPT_AIO }, 418 #endif 419 { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD }, 420 { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES }, 421 { "shared", 1, NULL, 'e' }, 422 { "format", 1, NULL, 'f' }, 423 { "persistent", 0, NULL, 't' }, 424 { "verbose", 0, NULL, 'v' }, 425 { NULL, 0, NULL, 0 } 426 }; 427 int ch; 428 int opt_ind = 0; 429 int li; 430 char *end; 431 int flags = BDRV_O_RDWR; 432 int partition = -1; 433 int ret = 0; 434 int fd; 435 bool seen_cache = false; 436 bool seen_discard = false; 437 #ifdef CONFIG_LINUX_AIO 438 bool seen_aio = false; 439 #endif 440 pthread_t client_thread; 441 const char *fmt = NULL; 442 Error *local_err = NULL; 443 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 444 QDict *options = NULL; 445 446 /* The client thread uses SIGTERM to interrupt the server. A signal 447 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 448 */ 449 struct sigaction sa_sigterm; 450 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 451 sa_sigterm.sa_handler = termsig_handler; 452 sigaction(SIGTERM, &sa_sigterm, NULL); 453 qemu_init_exec_dir(argv[0]); 454 455 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 456 switch (ch) { 457 case 's': 458 flags |= BDRV_O_SNAPSHOT; 459 break; 460 case 'n': 461 optarg = (char *) "none"; 462 /* fallthrough */ 463 case QEMU_NBD_OPT_CACHE: 464 if (seen_cache) { 465 errx(EXIT_FAILURE, "-n and --cache can only be specified once"); 466 } 467 seen_cache = true; 468 if (bdrv_parse_cache_flags(optarg, &flags) == -1) { 469 errx(EXIT_FAILURE, "Invalid cache mode `%s'", optarg); 470 } 471 break; 472 #ifdef CONFIG_LINUX_AIO 473 case QEMU_NBD_OPT_AIO: 474 if (seen_aio) { 475 errx(EXIT_FAILURE, "--aio can only be specified once"); 476 } 477 seen_aio = true; 478 if (!strcmp(optarg, "native")) { 479 flags |= BDRV_O_NATIVE_AIO; 480 } else if (!strcmp(optarg, "threads")) { 481 /* this is the default */ 482 } else { 483 errx(EXIT_FAILURE, "invalid aio mode `%s'", optarg); 484 } 485 break; 486 #endif 487 case QEMU_NBD_OPT_DISCARD: 488 if (seen_discard) { 489 errx(EXIT_FAILURE, "--discard can only be specified once"); 490 } 491 seen_discard = true; 492 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 493 errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg); 494 } 495 break; 496 case QEMU_NBD_OPT_DETECT_ZEROES: 497 detect_zeroes = 498 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 499 optarg, 500 BLOCKDEV_DETECT_ZEROES_OPTIONS_MAX, 501 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 502 &local_err); 503 if (local_err) { 504 errx(EXIT_FAILURE, "Failed to parse detect_zeroes mode: %s", 505 error_get_pretty(local_err)); 506 } 507 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 508 !(flags & BDRV_O_UNMAP)) { 509 errx(EXIT_FAILURE, "setting detect-zeroes to unmap is not allowed " 510 "without setting discard operation to unmap"); 511 } 512 break; 513 case 'b': 514 bindto = optarg; 515 break; 516 case 'p': 517 li = strtol(optarg, &end, 0); 518 if (*end) { 519 errx(EXIT_FAILURE, "Invalid port `%s'", optarg); 520 } 521 if (li < 1 || li > 65535) { 522 errx(EXIT_FAILURE, "Port out of range `%s'", optarg); 523 } 524 port = (uint16_t)li; 525 break; 526 case 'o': 527 dev_offset = strtoll (optarg, &end, 0); 528 if (*end) { 529 errx(EXIT_FAILURE, "Invalid offset `%s'", optarg); 530 } 531 if (dev_offset < 0) { 532 errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg); 533 } 534 break; 535 case 'l': 536 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 537 sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0); 538 if (!sn_opts) { 539 errx(EXIT_FAILURE, "Failed in parsing snapshot param `%s'", 540 optarg); 541 } 542 } else { 543 sn_id_or_name = optarg; 544 } 545 /* fall through */ 546 case 'r': 547 nbdflags |= NBD_FLAG_READ_ONLY; 548 flags &= ~BDRV_O_RDWR; 549 break; 550 case 'P': 551 partition = strtol(optarg, &end, 0); 552 if (*end) { 553 errx(EXIT_FAILURE, "Invalid partition `%s'", optarg); 554 } 555 if (partition < 1 || partition > 8) { 556 errx(EXIT_FAILURE, "Invalid partition %d", partition); 557 } 558 break; 559 case 'k': 560 sockpath = optarg; 561 if (sockpath[0] != '/') { 562 errx(EXIT_FAILURE, "socket path must be absolute\n"); 563 } 564 break; 565 case 'd': 566 disconnect = true; 567 break; 568 case 'c': 569 device = optarg; 570 break; 571 case 'e': 572 shared = strtol(optarg, &end, 0); 573 if (*end) { 574 errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg); 575 } 576 if (shared < 1) { 577 errx(EXIT_FAILURE, "Shared device number must be greater than 0\n"); 578 } 579 break; 580 case 'f': 581 fmt = optarg; 582 break; 583 case 't': 584 persistent = 1; 585 break; 586 case 'v': 587 verbose = 1; 588 break; 589 case 'V': 590 version(argv[0]); 591 exit(0); 592 break; 593 case 'h': 594 usage(argv[0]); 595 exit(0); 596 break; 597 case '?': 598 errx(EXIT_FAILURE, "Try `%s --help' for more information.", 599 argv[0]); 600 } 601 } 602 603 if ((argc - optind) != 1) { 604 errx(EXIT_FAILURE, "Invalid number of argument.\n" 605 "Try `%s --help' for more information.", 606 argv[0]); 607 } 608 609 if (disconnect) { 610 fd = open(argv[optind], O_RDWR); 611 if (fd < 0) { 612 err(EXIT_FAILURE, "Cannot open %s", argv[optind]); 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 err(EXIT_FAILURE, "Error setting up communication pipe"); 630 } 631 632 /* Now daemonize, but keep a communication channel open to 633 * print errors and exit with the proper status code. 634 */ 635 pid = fork(); 636 if (pid == 0) { 637 close(stderr_fd[0]); 638 ret = qemu_daemon(1, 0); 639 640 /* Temporarily redirect stderr to the parent's pipe... */ 641 dup2(stderr_fd[1], STDERR_FILENO); 642 if (ret < 0) { 643 err(EXIT_FAILURE, "Failed to daemonize"); 644 } 645 646 /* ... close the descriptor we inherited and go on. */ 647 close(stderr_fd[1]); 648 } else { 649 bool errors = false; 650 char *buf; 651 652 /* In the parent. Print error messages from the child until 653 * it closes the pipe. 654 */ 655 close(stderr_fd[1]); 656 buf = g_malloc(1024); 657 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 658 errors = true; 659 ret = qemu_write_full(STDERR_FILENO, buf, ret); 660 if (ret < 0) { 661 exit(EXIT_FAILURE); 662 } 663 } 664 if (ret < 0) { 665 err(EXIT_FAILURE, "Cannot read from daemon"); 666 } 667 668 /* Usually the daemon should not print any message. 669 * Exit with zero status in that case. 670 */ 671 exit(errors); 672 } 673 } 674 675 if (device != NULL && sockpath == NULL) { 676 sockpath = g_malloc(128); 677 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 678 } 679 680 if (qemu_init_main_loop(&local_err)) { 681 error_report_err(local_err); 682 exit(EXIT_FAILURE); 683 } 684 bdrv_init(); 685 atexit(bdrv_close_all); 686 687 if (fmt) { 688 options = qdict_new(); 689 qdict_put(options, "driver", qstring_from_str(fmt)); 690 } 691 692 srcpath = argv[optind]; 693 blk = blk_new_open("hda", srcpath, NULL, options, flags, &local_err); 694 if (!blk) { 695 errx(EXIT_FAILURE, "Failed to blk_new_open '%s': %s", argv[optind], 696 error_get_pretty(local_err)); 697 } 698 bs = blk_bs(blk); 699 700 if (sn_opts) { 701 ret = bdrv_snapshot_load_tmp(bs, 702 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 703 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 704 &local_err); 705 } else if (sn_id_or_name) { 706 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 707 &local_err); 708 } 709 if (ret < 0) { 710 errno = -ret; 711 err(EXIT_FAILURE, 712 "Failed to load snapshot: %s", 713 error_get_pretty(local_err)); 714 } 715 716 bs->detect_zeroes = detect_zeroes; 717 fd_size = blk_getlength(blk); 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); 728 729 if (sockpath) { 730 fd = unix_socket_incoming(sockpath); 731 } else { 732 fd = tcp_socket_incoming(bindto, port); 733 } 734 735 if (fd < 0) { 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 qemu_set_fd_handler2(fd, nbd_can_accept, nbd_accept, NULL, 753 (void *)(uintptr_t)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