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/osdep.h" 20 #include <getopt.h> 21 #include <libgen.h> 22 #include <pthread.h> 23 24 #include "qapi/error.h" 25 #include "qemu/cutils.h" 26 #include "sysemu/block-backend.h" 27 #include "block/block_int.h" 28 #include "block/nbd.h" 29 #include "qemu/main-loop.h" 30 #include "qemu/option.h" 31 #include "qemu/error-report.h" 32 #include "qemu/config-file.h" 33 #include "qemu/bswap.h" 34 #include "qemu/log.h" 35 #include "qemu/systemd.h" 36 #include "block/snapshot.h" 37 #include "qapi/qmp/qdict.h" 38 #include "qapi/qmp/qstring.h" 39 #include "qom/object_interfaces.h" 40 #include "io/channel-socket.h" 41 #include "io/net-listener.h" 42 #include "crypto/init.h" 43 #include "trace/control.h" 44 #include "qemu-version.h" 45 46 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 47 #define QEMU_NBD_OPT_CACHE 256 48 #define QEMU_NBD_OPT_AIO 257 49 #define QEMU_NBD_OPT_DISCARD 258 50 #define QEMU_NBD_OPT_DETECT_ZEROES 259 51 #define QEMU_NBD_OPT_OBJECT 260 52 #define QEMU_NBD_OPT_TLSCREDS 261 53 #define QEMU_NBD_OPT_IMAGE_OPTS 262 54 #define QEMU_NBD_OPT_FORK 263 55 56 #define MBR_SIZE 512 57 58 static NBDExport *exp; 59 static bool newproto; 60 static int verbose; 61 static char *srcpath; 62 static SocketAddress *saddr; 63 static int persistent = 0; 64 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 65 static int shared = 1; 66 static int nb_fds; 67 static QIONetListener *server; 68 static QCryptoTLSCreds *tlscreds; 69 70 static void usage(const char *name) 71 { 72 (printf) ( 73 "Usage: %s [OPTIONS] FILE\n" 74 "QEMU Disk Network Block Device Server\n" 75 "\n" 76 " -h, --help display this help and exit\n" 77 " -V, --version output version information and exit\n" 78 "\n" 79 "Connection properties:\n" 80 " -p, --port=PORT port to listen on (default `%d')\n" 81 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 82 " -k, --socket=PATH path to the unix socket\n" 83 " (default '"SOCKET_PATH"')\n" 84 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 85 " -t, --persistent don't exit on the last connection\n" 86 " -v, --verbose display extra debugging information\n" 87 " -x, --export-name=NAME expose export by name\n" 88 " -D, --description=TEXT with -x, also export a human-readable description\n" 89 "\n" 90 "Exposing part of the image:\n" 91 " -o, --offset=OFFSET offset into the image\n" 92 " -P, --partition=NUM only expose partition NUM\n" 93 "\n" 94 "General purpose options:\n" 95 " --object type,id=ID,... define an object such as 'secret' for providing\n" 96 " passwords and/or encryption keys\n" 97 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 98 " specify tracing options\n" 99 " --fork fork off the server process and exit the parent\n" 100 " once the server is running\n" 101 #ifdef __linux__ 102 "Kernel NBD client support:\n" 103 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 104 " -d, --disconnect disconnect the specified device\n" 105 "\n" 106 #endif 107 "\n" 108 "Block device options:\n" 109 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 110 " -r, --read-only export read-only\n" 111 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 112 " file with backing_file=FILE, redirect the write to\n" 113 " the temporary one\n" 114 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 115 " load an internal snapshot inside FILE and export it\n" 116 " as an read-only device, SNAPSHOT_PARAM format is\n" 117 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 118 " '[ID_OR_NAME]'\n" 119 " -n, --nocache disable host cache\n" 120 " --cache=MODE set cache mode (none, writeback, ...)\n" 121 " --aio=MODE set AIO mode (native or threads)\n" 122 " --discard=MODE set discard mode (ignore, unmap)\n" 123 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 124 " --image-opts treat FILE as a full set of image options\n" 125 "\n" 126 QEMU_HELP_BOTTOM "\n" 127 , name, NBD_DEFAULT_PORT, "DEVICE"); 128 } 129 130 static void version(const char *name) 131 { 132 printf( 133 "%s " QEMU_FULL_VERSION "\n" 134 "Written by Anthony Liguori.\n" 135 "\n" 136 QEMU_COPYRIGHT "\n" 137 "This is free software; see the source for copying conditions. There is NO\n" 138 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 139 , name); 140 } 141 142 struct partition_record 143 { 144 uint8_t bootable; 145 uint8_t start_head; 146 uint32_t start_cylinder; 147 uint8_t start_sector; 148 uint8_t system; 149 uint8_t end_head; 150 uint8_t end_cylinder; 151 uint8_t end_sector; 152 uint32_t start_sector_abs; 153 uint32_t nb_sectors_abs; 154 }; 155 156 static void read_partition(uint8_t *p, struct partition_record *r) 157 { 158 r->bootable = p[0]; 159 r->start_head = p[1]; 160 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 161 r->start_sector = p[2] & 0x3f; 162 r->system = p[4]; 163 r->end_head = p[5]; 164 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 165 r->end_sector = p[6] & 0x3f; 166 167 r->start_sector_abs = ldl_le_p(p + 8); 168 r->nb_sectors_abs = ldl_le_p(p + 12); 169 } 170 171 static int find_partition(BlockBackend *blk, int partition, 172 off_t *offset, off_t *size) 173 { 174 struct partition_record mbr[4]; 175 uint8_t data[MBR_SIZE]; 176 int i; 177 int ext_partnum = 4; 178 int ret; 179 180 ret = blk_pread(blk, 0, data, sizeof(data)); 181 if (ret < 0) { 182 error_report("error while reading: %s", strerror(-ret)); 183 exit(EXIT_FAILURE); 184 } 185 186 if (data[510] != 0x55 || data[511] != 0xaa) { 187 return -EINVAL; 188 } 189 190 for (i = 0; i < 4; i++) { 191 read_partition(&data[446 + 16 * i], &mbr[i]); 192 193 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 194 continue; 195 } 196 197 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 198 struct partition_record ext[4]; 199 uint8_t data1[MBR_SIZE]; 200 int j; 201 202 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, 203 data1, sizeof(data1)); 204 if (ret < 0) { 205 error_report("error while reading: %s", strerror(-ret)); 206 exit(EXIT_FAILURE); 207 } 208 209 for (j = 0; j < 4; j++) { 210 read_partition(&data1[446 + 16 * j], &ext[j]); 211 if (!ext[j].system || !ext[j].nb_sectors_abs) { 212 continue; 213 } 214 215 if ((ext_partnum + j + 1) == partition) { 216 *offset = (uint64_t)ext[j].start_sector_abs << 9; 217 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 218 return 0; 219 } 220 } 221 ext_partnum += 4; 222 } else if ((i + 1) == partition) { 223 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 224 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 225 return 0; 226 } 227 } 228 229 return -ENOENT; 230 } 231 232 static void termsig_handler(int signum) 233 { 234 atomic_cmpxchg(&state, RUNNING, TERMINATE); 235 qemu_notify_event(); 236 } 237 238 239 static void *show_parts(void *arg) 240 { 241 char *device = arg; 242 int nbd; 243 244 /* linux just needs an open() to trigger 245 * the partition table update 246 * but remember to load the module with max_part != 0 : 247 * modprobe nbd max_part=63 248 */ 249 nbd = open(device, O_RDWR); 250 if (nbd >= 0) { 251 close(nbd); 252 } 253 return NULL; 254 } 255 256 static void *nbd_client_thread(void *arg) 257 { 258 char *device = arg; 259 NBDExportInfo info = { .request_sizes = false, }; 260 QIOChannelSocket *sioc; 261 int fd; 262 int ret; 263 pthread_t show_parts_thread; 264 Error *local_error = NULL; 265 266 sioc = qio_channel_socket_new(); 267 if (qio_channel_socket_connect_sync(sioc, 268 saddr, 269 &local_error) < 0) { 270 error_report_err(local_error); 271 goto out; 272 } 273 274 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, 275 NULL, NULL, NULL, &info, &local_error); 276 if (ret < 0) { 277 if (local_error) { 278 error_report_err(local_error); 279 } 280 goto out_socket; 281 } 282 283 fd = open(device, O_RDWR); 284 if (fd < 0) { 285 /* Linux-only, we can use %m in printf. */ 286 error_report("Failed to open %s: %m", device); 287 goto out_socket; 288 } 289 290 ret = nbd_init(fd, sioc, &info, &local_error); 291 if (ret < 0) { 292 error_report_err(local_error); 293 goto out_fd; 294 } 295 296 /* update partition table */ 297 pthread_create(&show_parts_thread, NULL, show_parts, device); 298 299 if (verbose) { 300 fprintf(stderr, "NBD device %s is now connected to %s\n", 301 device, srcpath); 302 } else { 303 /* Close stderr so that the qemu-nbd process exits. */ 304 dup2(STDOUT_FILENO, STDERR_FILENO); 305 } 306 307 ret = nbd_client(fd); 308 if (ret) { 309 goto out_fd; 310 } 311 close(fd); 312 object_unref(OBJECT(sioc)); 313 kill(getpid(), SIGTERM); 314 return (void *) EXIT_SUCCESS; 315 316 out_fd: 317 close(fd); 318 out_socket: 319 object_unref(OBJECT(sioc)); 320 out: 321 kill(getpid(), SIGTERM); 322 return (void *) EXIT_FAILURE; 323 } 324 325 static int nbd_can_accept(void) 326 { 327 return state == RUNNING && nb_fds < shared; 328 } 329 330 static void nbd_export_closed(NBDExport *exp) 331 { 332 assert(state == TERMINATING); 333 state = TERMINATED; 334 } 335 336 static void nbd_update_server_watch(void); 337 338 static void nbd_client_closed(NBDClient *client, bool negotiated) 339 { 340 nb_fds--; 341 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 342 state = TERMINATE; 343 } 344 nbd_update_server_watch(); 345 nbd_client_put(client); 346 } 347 348 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 349 gpointer opaque) 350 { 351 if (state >= TERMINATE) { 352 return; 353 } 354 355 nb_fds++; 356 nbd_update_server_watch(); 357 nbd_client_new(newproto ? NULL : exp, cioc, 358 tlscreds, NULL, nbd_client_closed); 359 } 360 361 static void nbd_update_server_watch(void) 362 { 363 if (nbd_can_accept()) { 364 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 365 } else { 366 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 367 } 368 } 369 370 371 static SocketAddress *nbd_build_socket_address(const char *sockpath, 372 const char *bindto, 373 const char *port) 374 { 375 SocketAddress *saddr; 376 377 saddr = g_new0(SocketAddress, 1); 378 if (sockpath) { 379 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 380 saddr->u.q_unix.path = g_strdup(sockpath); 381 } else { 382 InetSocketAddress *inet; 383 saddr->type = SOCKET_ADDRESS_TYPE_INET; 384 inet = &saddr->u.inet; 385 inet->host = g_strdup(bindto); 386 if (port) { 387 inet->port = g_strdup(port); 388 } else { 389 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 390 } 391 } 392 393 return saddr; 394 } 395 396 397 static QemuOptsList file_opts = { 398 .name = "file", 399 .implied_opt_name = "file", 400 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 401 .desc = { 402 /* no elements => accept any params */ 403 { /* end of list */ } 404 }, 405 }; 406 407 static QemuOptsList qemu_object_opts = { 408 .name = "object", 409 .implied_opt_name = "qom-type", 410 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 411 .desc = { 412 { } 413 }, 414 }; 415 416 417 418 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 419 { 420 Object *obj; 421 QCryptoTLSCreds *creds; 422 423 obj = object_resolve_path_component( 424 object_get_objects_root(), id); 425 if (!obj) { 426 error_setg(errp, "No TLS credentials with id '%s'", 427 id); 428 return NULL; 429 } 430 creds = (QCryptoTLSCreds *) 431 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 432 if (!creds) { 433 error_setg(errp, "Object with id '%s' is not TLS credentials", 434 id); 435 return NULL; 436 } 437 438 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 439 error_setg(errp, 440 "Expecting TLS credentials with a server endpoint"); 441 return NULL; 442 } 443 object_ref(obj); 444 return creds; 445 } 446 447 static void setup_address_and_port(const char **address, const char **port) 448 { 449 if (*address == NULL) { 450 *address = "0.0.0.0"; 451 } 452 453 if (*port == NULL) { 454 *port = stringify(NBD_DEFAULT_PORT); 455 } 456 } 457 458 /* 459 * Check socket parameters compatibility when socket activation is used. 460 */ 461 static const char *socket_activation_validate_opts(const char *device, 462 const char *sockpath, 463 const char *address, 464 const char *port) 465 { 466 if (device != NULL) { 467 return "NBD device can't be set when using socket activation"; 468 } 469 470 if (sockpath != NULL) { 471 return "Unix socket can't be set when using socket activation"; 472 } 473 474 if (address != NULL) { 475 return "The interface can't be set when using socket activation"; 476 } 477 478 if (port != NULL) { 479 return "TCP port number can't be set when using socket activation"; 480 } 481 482 return NULL; 483 } 484 485 static void qemu_nbd_shutdown(void) 486 { 487 job_cancel_sync_all(); 488 bdrv_close_all(); 489 } 490 491 int main(int argc, char **argv) 492 { 493 BlockBackend *blk; 494 BlockDriverState *bs; 495 off_t dev_offset = 0; 496 uint16_t nbdflags = 0; 497 bool disconnect = false; 498 const char *bindto = NULL; 499 const char *port = NULL; 500 char *sockpath = NULL; 501 char *device = NULL; 502 off_t fd_size; 503 QemuOpts *sn_opts = NULL; 504 const char *sn_id_or_name = NULL; 505 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; 506 struct option lopt[] = { 507 { "help", no_argument, NULL, 'h' }, 508 { "version", no_argument, NULL, 'V' }, 509 { "bind", required_argument, NULL, 'b' }, 510 { "port", required_argument, NULL, 'p' }, 511 { "socket", required_argument, NULL, 'k' }, 512 { "offset", required_argument, NULL, 'o' }, 513 { "read-only", no_argument, NULL, 'r' }, 514 { "partition", required_argument, NULL, 'P' }, 515 { "connect", required_argument, NULL, 'c' }, 516 { "disconnect", no_argument, NULL, 'd' }, 517 { "snapshot", no_argument, NULL, 's' }, 518 { "load-snapshot", required_argument, NULL, 'l' }, 519 { "nocache", no_argument, NULL, 'n' }, 520 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 521 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 522 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 523 { "detect-zeroes", required_argument, NULL, 524 QEMU_NBD_OPT_DETECT_ZEROES }, 525 { "shared", required_argument, NULL, 'e' }, 526 { "format", required_argument, NULL, 'f' }, 527 { "persistent", no_argument, NULL, 't' }, 528 { "verbose", no_argument, NULL, 'v' }, 529 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 530 { "export-name", required_argument, NULL, 'x' }, 531 { "description", required_argument, NULL, 'D' }, 532 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 533 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 534 { "trace", required_argument, NULL, 'T' }, 535 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 536 { NULL, 0, NULL, 0 } 537 }; 538 int ch; 539 int opt_ind = 0; 540 char *end; 541 int flags = BDRV_O_RDWR; 542 int partition = -1; 543 int ret = 0; 544 bool seen_cache = false; 545 bool seen_discard = false; 546 bool seen_aio = false; 547 pthread_t client_thread; 548 const char *fmt = NULL; 549 Error *local_err = NULL; 550 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 551 QDict *options = NULL; 552 const char *export_name = NULL; 553 const char *export_description = NULL; 554 const char *tlscredsid = NULL; 555 bool imageOpts = false; 556 bool writethrough = true; 557 char *trace_file = NULL; 558 bool fork_process = false; 559 int old_stderr = -1; 560 unsigned socket_activation; 561 562 /* The client thread uses SIGTERM to interrupt the server. A signal 563 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 564 */ 565 struct sigaction sa_sigterm; 566 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 567 sa_sigterm.sa_handler = termsig_handler; 568 sigaction(SIGTERM, &sa_sigterm, NULL); 569 570 #ifdef CONFIG_POSIX 571 signal(SIGPIPE, SIG_IGN); 572 #endif 573 574 module_call_init(MODULE_INIT_TRACE); 575 qcrypto_init(&error_fatal); 576 577 module_call_init(MODULE_INIT_QOM); 578 qemu_add_opts(&qemu_object_opts); 579 qemu_add_opts(&qemu_trace_opts); 580 qemu_init_exec_dir(argv[0]); 581 582 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 583 switch (ch) { 584 case 's': 585 flags |= BDRV_O_SNAPSHOT; 586 break; 587 case 'n': 588 optarg = (char *) "none"; 589 /* fallthrough */ 590 case QEMU_NBD_OPT_CACHE: 591 if (seen_cache) { 592 error_report("-n and --cache can only be specified once"); 593 exit(EXIT_FAILURE); 594 } 595 seen_cache = true; 596 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 597 error_report("Invalid cache mode `%s'", optarg); 598 exit(EXIT_FAILURE); 599 } 600 break; 601 case QEMU_NBD_OPT_AIO: 602 if (seen_aio) { 603 error_report("--aio can only be specified once"); 604 exit(EXIT_FAILURE); 605 } 606 seen_aio = true; 607 if (!strcmp(optarg, "native")) { 608 flags |= BDRV_O_NATIVE_AIO; 609 } else if (!strcmp(optarg, "threads")) { 610 /* this is the default */ 611 } else { 612 error_report("invalid aio mode `%s'", optarg); 613 exit(EXIT_FAILURE); 614 } 615 break; 616 case QEMU_NBD_OPT_DISCARD: 617 if (seen_discard) { 618 error_report("--discard can only be specified once"); 619 exit(EXIT_FAILURE); 620 } 621 seen_discard = true; 622 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 623 error_report("Invalid discard mode `%s'", optarg); 624 exit(EXIT_FAILURE); 625 } 626 break; 627 case QEMU_NBD_OPT_DETECT_ZEROES: 628 detect_zeroes = 629 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 630 optarg, 631 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 632 &local_err); 633 if (local_err) { 634 error_reportf_err(local_err, 635 "Failed to parse detect_zeroes mode: "); 636 exit(EXIT_FAILURE); 637 } 638 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 639 !(flags & BDRV_O_UNMAP)) { 640 error_report("setting detect-zeroes to unmap is not allowed " 641 "without setting discard operation to unmap"); 642 exit(EXIT_FAILURE); 643 } 644 break; 645 case 'b': 646 bindto = optarg; 647 break; 648 case 'p': 649 port = optarg; 650 break; 651 case 'o': 652 dev_offset = strtoll (optarg, &end, 0); 653 if (*end) { 654 error_report("Invalid offset `%s'", optarg); 655 exit(EXIT_FAILURE); 656 } 657 if (dev_offset < 0) { 658 error_report("Offset must be positive `%s'", optarg); 659 exit(EXIT_FAILURE); 660 } 661 break; 662 case 'l': 663 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 664 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 665 optarg, false); 666 if (!sn_opts) { 667 error_report("Failed in parsing snapshot param `%s'", 668 optarg); 669 exit(EXIT_FAILURE); 670 } 671 } else { 672 sn_id_or_name = optarg; 673 } 674 /* fall through */ 675 case 'r': 676 nbdflags |= NBD_FLAG_READ_ONLY; 677 flags &= ~BDRV_O_RDWR; 678 break; 679 case 'P': 680 partition = strtol(optarg, &end, 0); 681 if (*end) { 682 error_report("Invalid partition `%s'", optarg); 683 exit(EXIT_FAILURE); 684 } 685 if (partition < 1 || partition > 8) { 686 error_report("Invalid partition %d", partition); 687 exit(EXIT_FAILURE); 688 } 689 break; 690 case 'k': 691 sockpath = optarg; 692 if (sockpath[0] != '/') { 693 error_report("socket path must be absolute"); 694 exit(EXIT_FAILURE); 695 } 696 break; 697 case 'd': 698 disconnect = true; 699 break; 700 case 'c': 701 device = optarg; 702 break; 703 case 'e': 704 shared = strtol(optarg, &end, 0); 705 if (*end) { 706 error_report("Invalid shared device number '%s'", optarg); 707 exit(EXIT_FAILURE); 708 } 709 if (shared < 1) { 710 error_report("Shared device number must be greater than 0"); 711 exit(EXIT_FAILURE); 712 } 713 break; 714 case 'f': 715 fmt = optarg; 716 break; 717 case 't': 718 persistent = 1; 719 break; 720 case 'x': 721 export_name = optarg; 722 break; 723 case 'D': 724 export_description = optarg; 725 break; 726 case 'v': 727 verbose = 1; 728 break; 729 case 'V': 730 version(argv[0]); 731 exit(0); 732 break; 733 case 'h': 734 usage(argv[0]); 735 exit(0); 736 break; 737 case '?': 738 error_report("Try `%s --help' for more information.", argv[0]); 739 exit(EXIT_FAILURE); 740 case QEMU_NBD_OPT_OBJECT: { 741 QemuOpts *opts; 742 opts = qemu_opts_parse_noisily(&qemu_object_opts, 743 optarg, true); 744 if (!opts) { 745 exit(EXIT_FAILURE); 746 } 747 } break; 748 case QEMU_NBD_OPT_TLSCREDS: 749 tlscredsid = optarg; 750 break; 751 case QEMU_NBD_OPT_IMAGE_OPTS: 752 imageOpts = true; 753 break; 754 case 'T': 755 g_free(trace_file); 756 trace_file = trace_opt_parse(optarg); 757 break; 758 case QEMU_NBD_OPT_FORK: 759 fork_process = true; 760 break; 761 } 762 } 763 764 if ((argc - optind) != 1) { 765 error_report("Invalid number of arguments"); 766 error_printf("Try `%s --help' for more information.\n", argv[0]); 767 exit(EXIT_FAILURE); 768 } 769 770 if (qemu_opts_foreach(&qemu_object_opts, 771 user_creatable_add_opts_foreach, 772 NULL, NULL)) { 773 exit(EXIT_FAILURE); 774 } 775 776 if (!trace_init_backends()) { 777 exit(1); 778 } 779 trace_init_file(trace_file); 780 qemu_set_log(LOG_TRACE); 781 782 socket_activation = check_socket_activation(); 783 if (socket_activation == 0) { 784 setup_address_and_port(&bindto, &port); 785 } else { 786 /* Using socket activation - check user didn't use -p etc. */ 787 const char *err_msg = socket_activation_validate_opts(device, sockpath, 788 bindto, port); 789 if (err_msg != NULL) { 790 error_report("%s", err_msg); 791 exit(EXIT_FAILURE); 792 } 793 794 /* qemu-nbd can only listen on a single socket. */ 795 if (socket_activation > 1) { 796 error_report("qemu-nbd does not support socket activation with %s > 1", 797 "LISTEN_FDS"); 798 exit(EXIT_FAILURE); 799 } 800 } 801 802 if (tlscredsid) { 803 if (sockpath) { 804 error_report("TLS is only supported with IPv4/IPv6"); 805 exit(EXIT_FAILURE); 806 } 807 if (device) { 808 error_report("TLS is not supported with a host device"); 809 exit(EXIT_FAILURE); 810 } 811 if (!export_name) { 812 /* Set the default NBD protocol export name, since 813 * we *must* use new style protocol for TLS */ 814 export_name = ""; 815 } 816 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 817 if (local_err) { 818 error_report("Failed to get TLS creds %s", 819 error_get_pretty(local_err)); 820 exit(EXIT_FAILURE); 821 } 822 } 823 824 if (disconnect) { 825 int nbdfd = open(argv[optind], O_RDWR); 826 if (nbdfd < 0) { 827 error_report("Cannot open %s: %s", argv[optind], 828 strerror(errno)); 829 exit(EXIT_FAILURE); 830 } 831 nbd_disconnect(nbdfd); 832 833 close(nbdfd); 834 835 printf("%s disconnected\n", argv[optind]); 836 837 return 0; 838 } 839 840 if ((device && !verbose) || fork_process) { 841 int stderr_fd[2]; 842 pid_t pid; 843 int ret; 844 845 if (qemu_pipe(stderr_fd) < 0) { 846 error_report("Error setting up communication pipe: %s", 847 strerror(errno)); 848 exit(EXIT_FAILURE); 849 } 850 851 /* Now daemonize, but keep a communication channel open to 852 * print errors and exit with the proper status code. 853 */ 854 pid = fork(); 855 if (pid < 0) { 856 error_report("Failed to fork: %s", strerror(errno)); 857 exit(EXIT_FAILURE); 858 } else if (pid == 0) { 859 close(stderr_fd[0]); 860 ret = qemu_daemon(1, 0); 861 862 /* Temporarily redirect stderr to the parent's pipe... */ 863 old_stderr = dup(STDERR_FILENO); 864 dup2(stderr_fd[1], STDERR_FILENO); 865 if (ret < 0) { 866 error_report("Failed to daemonize: %s", strerror(errno)); 867 exit(EXIT_FAILURE); 868 } 869 870 /* ... close the descriptor we inherited and go on. */ 871 close(stderr_fd[1]); 872 } else { 873 bool errors = false; 874 char *buf; 875 876 /* In the parent. Print error messages from the child until 877 * it closes the pipe. 878 */ 879 close(stderr_fd[1]); 880 buf = g_malloc(1024); 881 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 882 errors = true; 883 ret = qemu_write_full(STDERR_FILENO, buf, ret); 884 if (ret < 0) { 885 exit(EXIT_FAILURE); 886 } 887 } 888 if (ret < 0) { 889 error_report("Cannot read from daemon: %s", 890 strerror(errno)); 891 exit(EXIT_FAILURE); 892 } 893 894 /* Usually the daemon should not print any message. 895 * Exit with zero status in that case. 896 */ 897 exit(errors); 898 } 899 } 900 901 if (device != NULL && sockpath == NULL) { 902 sockpath = g_malloc(128); 903 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 904 } 905 906 server = qio_net_listener_new(); 907 if (socket_activation == 0) { 908 saddr = nbd_build_socket_address(sockpath, bindto, port); 909 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) { 910 object_unref(OBJECT(server)); 911 error_report_err(local_err); 912 exit(EXIT_FAILURE); 913 } 914 } else { 915 size_t i; 916 /* See comment in check_socket_activation above. */ 917 for (i = 0; i < socket_activation; i++) { 918 QIOChannelSocket *sioc; 919 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 920 &local_err); 921 if (sioc == NULL) { 922 object_unref(OBJECT(server)); 923 error_report("Failed to use socket activation: %s", 924 error_get_pretty(local_err)); 925 exit(EXIT_FAILURE); 926 } 927 qio_net_listener_add(server, sioc); 928 object_unref(OBJECT(sioc)); 929 } 930 } 931 932 if (qemu_init_main_loop(&local_err)) { 933 error_report_err(local_err); 934 exit(EXIT_FAILURE); 935 } 936 bdrv_init(); 937 atexit(qemu_nbd_shutdown); 938 939 srcpath = argv[optind]; 940 if (imageOpts) { 941 QemuOpts *opts; 942 if (fmt) { 943 error_report("--image-opts and -f are mutually exclusive"); 944 exit(EXIT_FAILURE); 945 } 946 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 947 if (!opts) { 948 qemu_opts_reset(&file_opts); 949 exit(EXIT_FAILURE); 950 } 951 options = qemu_opts_to_qdict(opts, NULL); 952 qemu_opts_reset(&file_opts); 953 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 954 } else { 955 if (fmt) { 956 options = qdict_new(); 957 qdict_put_str(options, "driver", fmt); 958 } 959 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 960 } 961 962 if (!blk) { 963 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 964 argv[optind]); 965 exit(EXIT_FAILURE); 966 } 967 bs = blk_bs(blk); 968 969 blk_set_enable_write_cache(blk, !writethrough); 970 971 if (sn_opts) { 972 ret = bdrv_snapshot_load_tmp(bs, 973 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 974 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 975 &local_err); 976 } else if (sn_id_or_name) { 977 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 978 &local_err); 979 } 980 if (ret < 0) { 981 error_reportf_err(local_err, "Failed to load snapshot: "); 982 exit(EXIT_FAILURE); 983 } 984 985 bs->detect_zeroes = detect_zeroes; 986 fd_size = blk_getlength(blk); 987 if (fd_size < 0) { 988 error_report("Failed to determine the image length: %s", 989 strerror(-fd_size)); 990 exit(EXIT_FAILURE); 991 } 992 993 if (dev_offset >= fd_size) { 994 error_report("Offset (%lld) has to be smaller than the image size " 995 "(%lld)", 996 (long long int)dev_offset, (long long int)fd_size); 997 exit(EXIT_FAILURE); 998 } 999 fd_size -= dev_offset; 1000 1001 if (partition != -1) { 1002 ret = find_partition(blk, partition, &dev_offset, &fd_size); 1003 if (ret < 0) { 1004 error_report("Could not find partition %d: %s", partition, 1005 strerror(-ret)); 1006 exit(EXIT_FAILURE); 1007 } 1008 } 1009 1010 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1011 writethrough, NULL, &local_err); 1012 if (!exp) { 1013 error_report_err(local_err); 1014 exit(EXIT_FAILURE); 1015 } 1016 if (export_name) { 1017 nbd_export_set_name(exp, export_name); 1018 nbd_export_set_description(exp, export_description); 1019 newproto = true; 1020 } else if (export_description) { 1021 error_report("Export description requires an export name"); 1022 exit(EXIT_FAILURE); 1023 } 1024 1025 if (device) { 1026 int ret; 1027 1028 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1029 if (ret != 0) { 1030 error_report("Failed to create client thread: %s", strerror(ret)); 1031 exit(EXIT_FAILURE); 1032 } 1033 } else { 1034 /* Shut up GCC warnings. */ 1035 memset(&client_thread, 0, sizeof(client_thread)); 1036 } 1037 1038 nbd_update_server_watch(); 1039 1040 /* now when the initialization is (almost) complete, chdir("/") 1041 * to free any busy filesystems */ 1042 if (chdir("/") < 0) { 1043 error_report("Could not chdir to root directory: %s", 1044 strerror(errno)); 1045 exit(EXIT_FAILURE); 1046 } 1047 1048 if (fork_process) { 1049 dup2(old_stderr, STDERR_FILENO); 1050 close(old_stderr); 1051 } 1052 1053 state = RUNNING; 1054 do { 1055 main_loop_wait(false); 1056 if (state == TERMINATE) { 1057 state = TERMINATING; 1058 nbd_export_close(exp); 1059 nbd_export_put(exp); 1060 exp = NULL; 1061 } 1062 } while (state != TERMINATED); 1063 1064 blk_unref(blk); 1065 if (sockpath) { 1066 unlink(sockpath); 1067 } 1068 1069 qemu_opts_del(sn_opts); 1070 1071 if (device) { 1072 void *ret; 1073 pthread_join(client_thread, &ret); 1074 exit(ret != NULL); 1075 } else { 1076 exit(EXIT_SUCCESS); 1077 } 1078 } 1079