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 int verbose; 60 static char *srcpath; 61 static SocketAddress *saddr; 62 static int persistent = 0; 63 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 64 static int shared = 1; 65 static int nb_fds; 66 static QIONetListener *server; 67 static QCryptoTLSCreds *tlscreds; 68 69 static void usage(const char *name) 70 { 71 (printf) ( 72 "Usage: %s [OPTIONS] FILE\n" 73 "QEMU Disk Network Block Device Server\n" 74 "\n" 75 " -h, --help display this help and exit\n" 76 " -V, --version output version information and exit\n" 77 "\n" 78 "Connection properties:\n" 79 " -p, --port=PORT port to listen on (default `%d')\n" 80 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 81 " -k, --socket=PATH path to the unix socket\n" 82 " (default '"SOCKET_PATH"')\n" 83 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 84 " -t, --persistent don't exit on the last connection\n" 85 " -v, --verbose display extra debugging information\n" 86 " -x, --export-name=NAME expose export by name (default is empty string)\n" 87 " -D, --description=TEXT export a human-readable description\n" 88 "\n" 89 "Exposing part of the image:\n" 90 " -o, --offset=OFFSET offset into the image\n" 91 " -P, --partition=NUM only expose partition NUM\n" 92 "\n" 93 "General purpose options:\n" 94 " --object type,id=ID,... define an object such as 'secret' for providing\n" 95 " passwords and/or encryption keys\n" 96 " --tls-creds=ID use id of an earlier --object to provide TLS\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(cioc, tlscreds, NULL, nbd_client_closed); 358 } 359 360 static void nbd_update_server_watch(void) 361 { 362 if (nbd_can_accept()) { 363 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 364 } else { 365 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 366 } 367 } 368 369 370 static SocketAddress *nbd_build_socket_address(const char *sockpath, 371 const char *bindto, 372 const char *port) 373 { 374 SocketAddress *saddr; 375 376 saddr = g_new0(SocketAddress, 1); 377 if (sockpath) { 378 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 379 saddr->u.q_unix.path = g_strdup(sockpath); 380 } else { 381 InetSocketAddress *inet; 382 saddr->type = SOCKET_ADDRESS_TYPE_INET; 383 inet = &saddr->u.inet; 384 inet->host = g_strdup(bindto); 385 if (port) { 386 inet->port = g_strdup(port); 387 } else { 388 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 389 } 390 } 391 392 return saddr; 393 } 394 395 396 static QemuOptsList file_opts = { 397 .name = "file", 398 .implied_opt_name = "file", 399 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 400 .desc = { 401 /* no elements => accept any params */ 402 { /* end of list */ } 403 }, 404 }; 405 406 static QemuOptsList qemu_object_opts = { 407 .name = "object", 408 .implied_opt_name = "qom-type", 409 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 410 .desc = { 411 { } 412 }, 413 }; 414 415 416 417 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 418 { 419 Object *obj; 420 QCryptoTLSCreds *creds; 421 422 obj = object_resolve_path_component( 423 object_get_objects_root(), id); 424 if (!obj) { 425 error_setg(errp, "No TLS credentials with id '%s'", 426 id); 427 return NULL; 428 } 429 creds = (QCryptoTLSCreds *) 430 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 431 if (!creds) { 432 error_setg(errp, "Object with id '%s' is not TLS credentials", 433 id); 434 return NULL; 435 } 436 437 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 438 error_setg(errp, 439 "Expecting TLS credentials with a server endpoint"); 440 return NULL; 441 } 442 object_ref(obj); 443 return creds; 444 } 445 446 static void setup_address_and_port(const char **address, const char **port) 447 { 448 if (*address == NULL) { 449 *address = "0.0.0.0"; 450 } 451 452 if (*port == NULL) { 453 *port = stringify(NBD_DEFAULT_PORT); 454 } 455 } 456 457 /* 458 * Check socket parameters compatibility when socket activation is used. 459 */ 460 static const char *socket_activation_validate_opts(const char *device, 461 const char *sockpath, 462 const char *address, 463 const char *port) 464 { 465 if (device != NULL) { 466 return "NBD device can't be set when using socket activation"; 467 } 468 469 if (sockpath != NULL) { 470 return "Unix socket can't be set when using socket activation"; 471 } 472 473 if (address != NULL) { 474 return "The interface can't be set when using socket activation"; 475 } 476 477 if (port != NULL) { 478 return "TCP port number can't be set when using socket activation"; 479 } 480 481 return NULL; 482 } 483 484 static void qemu_nbd_shutdown(void) 485 { 486 job_cancel_sync_all(); 487 bdrv_close_all(); 488 } 489 490 int main(int argc, char **argv) 491 { 492 BlockBackend *blk; 493 BlockDriverState *bs; 494 off_t dev_offset = 0; 495 uint16_t nbdflags = 0; 496 bool disconnect = false; 497 const char *bindto = NULL; 498 const char *port = NULL; 499 char *sockpath = NULL; 500 char *device = NULL; 501 off_t fd_size; 502 QemuOpts *sn_opts = NULL; 503 const char *sn_id_or_name = NULL; 504 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; 505 struct option lopt[] = { 506 { "help", no_argument, NULL, 'h' }, 507 { "version", no_argument, NULL, 'V' }, 508 { "bind", required_argument, NULL, 'b' }, 509 { "port", required_argument, NULL, 'p' }, 510 { "socket", required_argument, NULL, 'k' }, 511 { "offset", required_argument, NULL, 'o' }, 512 { "read-only", no_argument, NULL, 'r' }, 513 { "partition", required_argument, NULL, 'P' }, 514 { "connect", required_argument, NULL, 'c' }, 515 { "disconnect", no_argument, NULL, 'd' }, 516 { "snapshot", no_argument, NULL, 's' }, 517 { "load-snapshot", required_argument, NULL, 'l' }, 518 { "nocache", no_argument, NULL, 'n' }, 519 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 520 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 521 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 522 { "detect-zeroes", required_argument, NULL, 523 QEMU_NBD_OPT_DETECT_ZEROES }, 524 { "shared", required_argument, NULL, 'e' }, 525 { "format", required_argument, NULL, 'f' }, 526 { "persistent", no_argument, NULL, 't' }, 527 { "verbose", no_argument, NULL, 'v' }, 528 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 529 { "export-name", required_argument, NULL, 'x' }, 530 { "description", required_argument, NULL, 'D' }, 531 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 532 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 533 { "trace", required_argument, NULL, 'T' }, 534 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 535 { NULL, 0, NULL, 0 } 536 }; 537 int ch; 538 int opt_ind = 0; 539 char *end; 540 int flags = BDRV_O_RDWR; 541 int partition = -1; 542 int ret = 0; 543 bool seen_cache = false; 544 bool seen_discard = false; 545 bool seen_aio = false; 546 pthread_t client_thread; 547 const char *fmt = NULL; 548 Error *local_err = NULL; 549 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 550 QDict *options = NULL; 551 const char *export_name = ""; /* Default export name */ 552 const char *export_description = NULL; 553 const char *tlscredsid = NULL; 554 bool imageOpts = false; 555 bool writethrough = true; 556 char *trace_file = NULL; 557 bool fork_process = false; 558 int old_stderr = -1; 559 unsigned socket_activation; 560 561 /* The client thread uses SIGTERM to interrupt the server. A signal 562 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 563 */ 564 struct sigaction sa_sigterm; 565 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 566 sa_sigterm.sa_handler = termsig_handler; 567 sigaction(SIGTERM, &sa_sigterm, NULL); 568 569 #ifdef CONFIG_POSIX 570 signal(SIGPIPE, SIG_IGN); 571 #endif 572 573 module_call_init(MODULE_INIT_TRACE); 574 qcrypto_init(&error_fatal); 575 576 module_call_init(MODULE_INIT_QOM); 577 qemu_add_opts(&qemu_object_opts); 578 qemu_add_opts(&qemu_trace_opts); 579 qemu_init_exec_dir(argv[0]); 580 581 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 582 switch (ch) { 583 case 's': 584 flags |= BDRV_O_SNAPSHOT; 585 break; 586 case 'n': 587 optarg = (char *) "none"; 588 /* fallthrough */ 589 case QEMU_NBD_OPT_CACHE: 590 if (seen_cache) { 591 error_report("-n and --cache can only be specified once"); 592 exit(EXIT_FAILURE); 593 } 594 seen_cache = true; 595 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 596 error_report("Invalid cache mode `%s'", optarg); 597 exit(EXIT_FAILURE); 598 } 599 break; 600 case QEMU_NBD_OPT_AIO: 601 if (seen_aio) { 602 error_report("--aio can only be specified once"); 603 exit(EXIT_FAILURE); 604 } 605 seen_aio = true; 606 if (!strcmp(optarg, "native")) { 607 flags |= BDRV_O_NATIVE_AIO; 608 } else if (!strcmp(optarg, "threads")) { 609 /* this is the default */ 610 } else { 611 error_report("invalid aio mode `%s'", optarg); 612 exit(EXIT_FAILURE); 613 } 614 break; 615 case QEMU_NBD_OPT_DISCARD: 616 if (seen_discard) { 617 error_report("--discard can only be specified once"); 618 exit(EXIT_FAILURE); 619 } 620 seen_discard = true; 621 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 622 error_report("Invalid discard mode `%s'", optarg); 623 exit(EXIT_FAILURE); 624 } 625 break; 626 case QEMU_NBD_OPT_DETECT_ZEROES: 627 detect_zeroes = 628 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 629 optarg, 630 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 631 &local_err); 632 if (local_err) { 633 error_reportf_err(local_err, 634 "Failed to parse detect_zeroes mode: "); 635 exit(EXIT_FAILURE); 636 } 637 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 638 !(flags & BDRV_O_UNMAP)) { 639 error_report("setting detect-zeroes to unmap is not allowed " 640 "without setting discard operation to unmap"); 641 exit(EXIT_FAILURE); 642 } 643 break; 644 case 'b': 645 bindto = optarg; 646 break; 647 case 'p': 648 port = optarg; 649 break; 650 case 'o': 651 dev_offset = strtoll (optarg, &end, 0); 652 if (*end) { 653 error_report("Invalid offset `%s'", optarg); 654 exit(EXIT_FAILURE); 655 } 656 if (dev_offset < 0) { 657 error_report("Offset must be positive `%s'", optarg); 658 exit(EXIT_FAILURE); 659 } 660 break; 661 case 'l': 662 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 663 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 664 optarg, false); 665 if (!sn_opts) { 666 error_report("Failed in parsing snapshot param `%s'", 667 optarg); 668 exit(EXIT_FAILURE); 669 } 670 } else { 671 sn_id_or_name = optarg; 672 } 673 /* fall through */ 674 case 'r': 675 nbdflags |= NBD_FLAG_READ_ONLY; 676 flags &= ~BDRV_O_RDWR; 677 break; 678 case 'P': 679 partition = strtol(optarg, &end, 0); 680 if (*end) { 681 error_report("Invalid partition `%s'", optarg); 682 exit(EXIT_FAILURE); 683 } 684 if (partition < 1 || partition > 8) { 685 error_report("Invalid partition %d", partition); 686 exit(EXIT_FAILURE); 687 } 688 break; 689 case 'k': 690 sockpath = optarg; 691 if (sockpath[0] != '/') { 692 error_report("socket path must be absolute"); 693 exit(EXIT_FAILURE); 694 } 695 break; 696 case 'd': 697 disconnect = true; 698 break; 699 case 'c': 700 device = optarg; 701 break; 702 case 'e': 703 shared = strtol(optarg, &end, 0); 704 if (*end) { 705 error_report("Invalid shared device number '%s'", optarg); 706 exit(EXIT_FAILURE); 707 } 708 if (shared < 1) { 709 error_report("Shared device number must be greater than 0"); 710 exit(EXIT_FAILURE); 711 } 712 break; 713 case 'f': 714 fmt = optarg; 715 break; 716 case 't': 717 persistent = 1; 718 break; 719 case 'x': 720 export_name = optarg; 721 break; 722 case 'D': 723 export_description = optarg; 724 break; 725 case 'v': 726 verbose = 1; 727 break; 728 case 'V': 729 version(argv[0]); 730 exit(0); 731 break; 732 case 'h': 733 usage(argv[0]); 734 exit(0); 735 break; 736 case '?': 737 error_report("Try `%s --help' for more information.", argv[0]); 738 exit(EXIT_FAILURE); 739 case QEMU_NBD_OPT_OBJECT: { 740 QemuOpts *opts; 741 opts = qemu_opts_parse_noisily(&qemu_object_opts, 742 optarg, true); 743 if (!opts) { 744 exit(EXIT_FAILURE); 745 } 746 } break; 747 case QEMU_NBD_OPT_TLSCREDS: 748 tlscredsid = optarg; 749 break; 750 case QEMU_NBD_OPT_IMAGE_OPTS: 751 imageOpts = true; 752 break; 753 case 'T': 754 g_free(trace_file); 755 trace_file = trace_opt_parse(optarg); 756 break; 757 case QEMU_NBD_OPT_FORK: 758 fork_process = true; 759 break; 760 } 761 } 762 763 if ((argc - optind) != 1) { 764 error_report("Invalid number of arguments"); 765 error_printf("Try `%s --help' for more information.\n", argv[0]); 766 exit(EXIT_FAILURE); 767 } 768 769 if (qemu_opts_foreach(&qemu_object_opts, 770 user_creatable_add_opts_foreach, 771 NULL, NULL)) { 772 exit(EXIT_FAILURE); 773 } 774 775 if (!trace_init_backends()) { 776 exit(1); 777 } 778 trace_init_file(trace_file); 779 qemu_set_log(LOG_TRACE); 780 781 socket_activation = check_socket_activation(); 782 if (socket_activation == 0) { 783 setup_address_and_port(&bindto, &port); 784 } else { 785 /* Using socket activation - check user didn't use -p etc. */ 786 const char *err_msg = socket_activation_validate_opts(device, sockpath, 787 bindto, port); 788 if (err_msg != NULL) { 789 error_report("%s", err_msg); 790 exit(EXIT_FAILURE); 791 } 792 793 /* qemu-nbd can only listen on a single socket. */ 794 if (socket_activation > 1) { 795 error_report("qemu-nbd does not support socket activation with %s > 1", 796 "LISTEN_FDS"); 797 exit(EXIT_FAILURE); 798 } 799 } 800 801 if (tlscredsid) { 802 if (sockpath) { 803 error_report("TLS is only supported with IPv4/IPv6"); 804 exit(EXIT_FAILURE); 805 } 806 if (device) { 807 error_report("TLS is not supported with a host device"); 808 exit(EXIT_FAILURE); 809 } 810 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 811 if (local_err) { 812 error_report("Failed to get TLS creds %s", 813 error_get_pretty(local_err)); 814 exit(EXIT_FAILURE); 815 } 816 } 817 818 if (disconnect) { 819 int nbdfd = open(argv[optind], O_RDWR); 820 if (nbdfd < 0) { 821 error_report("Cannot open %s: %s", argv[optind], 822 strerror(errno)); 823 exit(EXIT_FAILURE); 824 } 825 nbd_disconnect(nbdfd); 826 827 close(nbdfd); 828 829 printf("%s disconnected\n", argv[optind]); 830 831 return 0; 832 } 833 834 if ((device && !verbose) || fork_process) { 835 int stderr_fd[2]; 836 pid_t pid; 837 int ret; 838 839 if (qemu_pipe(stderr_fd) < 0) { 840 error_report("Error setting up communication pipe: %s", 841 strerror(errno)); 842 exit(EXIT_FAILURE); 843 } 844 845 /* Now daemonize, but keep a communication channel open to 846 * print errors and exit with the proper status code. 847 */ 848 pid = fork(); 849 if (pid < 0) { 850 error_report("Failed to fork: %s", strerror(errno)); 851 exit(EXIT_FAILURE); 852 } else if (pid == 0) { 853 close(stderr_fd[0]); 854 ret = qemu_daemon(1, 0); 855 856 /* Temporarily redirect stderr to the parent's pipe... */ 857 old_stderr = dup(STDERR_FILENO); 858 dup2(stderr_fd[1], STDERR_FILENO); 859 if (ret < 0) { 860 error_report("Failed to daemonize: %s", strerror(errno)); 861 exit(EXIT_FAILURE); 862 } 863 864 /* ... close the descriptor we inherited and go on. */ 865 close(stderr_fd[1]); 866 } else { 867 bool errors = false; 868 char *buf; 869 870 /* In the parent. Print error messages from the child until 871 * it closes the pipe. 872 */ 873 close(stderr_fd[1]); 874 buf = g_malloc(1024); 875 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 876 errors = true; 877 ret = qemu_write_full(STDERR_FILENO, buf, ret); 878 if (ret < 0) { 879 exit(EXIT_FAILURE); 880 } 881 } 882 if (ret < 0) { 883 error_report("Cannot read from daemon: %s", 884 strerror(errno)); 885 exit(EXIT_FAILURE); 886 } 887 888 /* Usually the daemon should not print any message. 889 * Exit with zero status in that case. 890 */ 891 exit(errors); 892 } 893 } 894 895 if (device != NULL && sockpath == NULL) { 896 sockpath = g_malloc(128); 897 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 898 } 899 900 server = qio_net_listener_new(); 901 if (socket_activation == 0) { 902 saddr = nbd_build_socket_address(sockpath, bindto, port); 903 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) { 904 object_unref(OBJECT(server)); 905 error_report_err(local_err); 906 exit(EXIT_FAILURE); 907 } 908 } else { 909 size_t i; 910 /* See comment in check_socket_activation above. */ 911 for (i = 0; i < socket_activation; i++) { 912 QIOChannelSocket *sioc; 913 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 914 &local_err); 915 if (sioc == NULL) { 916 object_unref(OBJECT(server)); 917 error_report("Failed to use socket activation: %s", 918 error_get_pretty(local_err)); 919 exit(EXIT_FAILURE); 920 } 921 qio_net_listener_add(server, sioc); 922 object_unref(OBJECT(sioc)); 923 } 924 } 925 926 if (qemu_init_main_loop(&local_err)) { 927 error_report_err(local_err); 928 exit(EXIT_FAILURE); 929 } 930 bdrv_init(); 931 atexit(qemu_nbd_shutdown); 932 933 srcpath = argv[optind]; 934 if (imageOpts) { 935 QemuOpts *opts; 936 if (fmt) { 937 error_report("--image-opts and -f are mutually exclusive"); 938 exit(EXIT_FAILURE); 939 } 940 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 941 if (!opts) { 942 qemu_opts_reset(&file_opts); 943 exit(EXIT_FAILURE); 944 } 945 options = qemu_opts_to_qdict(opts, NULL); 946 qemu_opts_reset(&file_opts); 947 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 948 } else { 949 if (fmt) { 950 options = qdict_new(); 951 qdict_put_str(options, "driver", fmt); 952 } 953 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 954 } 955 956 if (!blk) { 957 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 958 argv[optind]); 959 exit(EXIT_FAILURE); 960 } 961 bs = blk_bs(blk); 962 963 blk_set_enable_write_cache(blk, !writethrough); 964 965 if (sn_opts) { 966 ret = bdrv_snapshot_load_tmp(bs, 967 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 968 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 969 &local_err); 970 } else if (sn_id_or_name) { 971 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 972 &local_err); 973 } 974 if (ret < 0) { 975 error_reportf_err(local_err, "Failed to load snapshot: "); 976 exit(EXIT_FAILURE); 977 } 978 979 bs->detect_zeroes = detect_zeroes; 980 fd_size = blk_getlength(blk); 981 if (fd_size < 0) { 982 error_report("Failed to determine the image length: %s", 983 strerror(-fd_size)); 984 exit(EXIT_FAILURE); 985 } 986 987 if (dev_offset >= fd_size) { 988 error_report("Offset (%lld) has to be smaller than the image size " 989 "(%lld)", 990 (long long int)dev_offset, (long long int)fd_size); 991 exit(EXIT_FAILURE); 992 } 993 fd_size -= dev_offset; 994 995 if (partition != -1) { 996 ret = find_partition(blk, partition, &dev_offset, &fd_size); 997 if (ret < 0) { 998 error_report("Could not find partition %d: %s", partition, 999 strerror(-ret)); 1000 exit(EXIT_FAILURE); 1001 } 1002 } 1003 1004 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1005 writethrough, NULL, &local_err); 1006 if (!exp) { 1007 error_report_err(local_err); 1008 exit(EXIT_FAILURE); 1009 } 1010 nbd_export_set_name(exp, export_name); 1011 nbd_export_set_description(exp, export_description); 1012 1013 if (device) { 1014 int ret; 1015 1016 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1017 if (ret != 0) { 1018 error_report("Failed to create client thread: %s", strerror(ret)); 1019 exit(EXIT_FAILURE); 1020 } 1021 } else { 1022 /* Shut up GCC warnings. */ 1023 memset(&client_thread, 0, sizeof(client_thread)); 1024 } 1025 1026 nbd_update_server_watch(); 1027 1028 /* now when the initialization is (almost) complete, chdir("/") 1029 * to free any busy filesystems */ 1030 if (chdir("/") < 0) { 1031 error_report("Could not chdir to root directory: %s", 1032 strerror(errno)); 1033 exit(EXIT_FAILURE); 1034 } 1035 1036 if (fork_process) { 1037 dup2(old_stderr, STDERR_FILENO); 1038 close(old_stderr); 1039 } 1040 1041 state = RUNNING; 1042 do { 1043 main_loop_wait(false); 1044 if (state == TERMINATE) { 1045 state = TERMINATING; 1046 nbd_export_close(exp); 1047 nbd_export_put(exp); 1048 exp = NULL; 1049 } 1050 } while (state != TERMINATED); 1051 1052 blk_unref(blk); 1053 if (sockpath) { 1054 unlink(sockpath); 1055 } 1056 1057 qemu_opts_del(sn_opts); 1058 1059 if (device) { 1060 void *ret; 1061 pthread_join(client_thread, &ret); 1062 exit(ret != NULL); 1063 } else { 1064 exit(EXIT_SUCCESS); 1065 } 1066 } 1067