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 #ifdef __linux__ 47 #define HAVE_NBD_DEVICE 1 48 #else 49 #define HAVE_NBD_DEVICE 0 50 #endif 51 52 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 53 #define QEMU_NBD_OPT_CACHE 256 54 #define QEMU_NBD_OPT_AIO 257 55 #define QEMU_NBD_OPT_DISCARD 258 56 #define QEMU_NBD_OPT_DETECT_ZEROES 259 57 #define QEMU_NBD_OPT_OBJECT 260 58 #define QEMU_NBD_OPT_TLSCREDS 261 59 #define QEMU_NBD_OPT_IMAGE_OPTS 262 60 #define QEMU_NBD_OPT_FORK 263 61 62 #define MBR_SIZE 512 63 64 static NBDExport *export; 65 static int verbose; 66 static char *srcpath; 67 static SocketAddress *saddr; 68 static int persistent = 0; 69 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 70 static int shared = 1; 71 static int nb_fds; 72 static QIONetListener *server; 73 static QCryptoTLSCreds *tlscreds; 74 75 static void usage(const char *name) 76 { 77 (printf) ( 78 "Usage: %s [OPTIONS] FILE\n" 79 "QEMU Disk Network Block Device Server\n" 80 "\n" 81 " -h, --help display this help and exit\n" 82 " -V, --version output version information and exit\n" 83 "\n" 84 "Connection properties:\n" 85 " -p, --port=PORT port to listen on (default `%d')\n" 86 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 87 " -k, --socket=PATH path to the unix socket\n" 88 " (default '"SOCKET_PATH"')\n" 89 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 90 " -t, --persistent don't exit on the last connection\n" 91 " -v, --verbose display extra debugging information\n" 92 " -x, --export-name=NAME expose export by name (default is empty string)\n" 93 " -D, --description=TEXT export a human-readable description\n" 94 "\n" 95 "Exposing part of the image:\n" 96 " -o, --offset=OFFSET offset into the image\n" 97 " -P, --partition=NUM only expose partition NUM\n" 98 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 99 "\n" 100 "General purpose options:\n" 101 " --object type,id=ID,... define an object such as 'secret' for providing\n" 102 " passwords and/or encryption keys\n" 103 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 104 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 105 " specify tracing options\n" 106 " --fork fork off the server process and exit the parent\n" 107 " once the server is running\n" 108 #if HAVE_NBD_DEVICE 109 "\n" 110 "Kernel NBD client support:\n" 111 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 112 " -d, --disconnect disconnect the specified device\n" 113 #endif 114 "\n" 115 "Block device options:\n" 116 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 117 " -r, --read-only export read-only\n" 118 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 119 " file with backing_file=FILE, redirect the write to\n" 120 " the temporary one\n" 121 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 122 " load an internal snapshot inside FILE and export it\n" 123 " as an read-only device, SNAPSHOT_PARAM format is\n" 124 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 125 " '[ID_OR_NAME]'\n" 126 " -n, --nocache disable host cache\n" 127 " --cache=MODE set cache mode (none, writeback, ...)\n" 128 " --aio=MODE set AIO mode (native or threads)\n" 129 " --discard=MODE set discard mode (ignore, unmap)\n" 130 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 131 " --image-opts treat FILE as a full set of image options\n" 132 "\n" 133 QEMU_HELP_BOTTOM "\n" 134 , name, NBD_DEFAULT_PORT, "DEVICE"); 135 } 136 137 static void version(const char *name) 138 { 139 printf( 140 "%s " QEMU_FULL_VERSION "\n" 141 "Written by Anthony Liguori.\n" 142 "\n" 143 QEMU_COPYRIGHT "\n" 144 "This is free software; see the source for copying conditions. There is NO\n" 145 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 146 , name); 147 } 148 149 struct partition_record 150 { 151 uint8_t bootable; 152 uint8_t start_head; 153 uint32_t start_cylinder; 154 uint8_t start_sector; 155 uint8_t system; 156 uint8_t end_head; 157 uint8_t end_cylinder; 158 uint8_t end_sector; 159 uint32_t start_sector_abs; 160 uint32_t nb_sectors_abs; 161 }; 162 163 static void read_partition(uint8_t *p, struct partition_record *r) 164 { 165 r->bootable = p[0]; 166 r->start_head = p[1]; 167 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 168 r->start_sector = p[2] & 0x3f; 169 r->system = p[4]; 170 r->end_head = p[5]; 171 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 172 r->end_sector = p[6] & 0x3f; 173 174 r->start_sector_abs = ldl_le_p(p + 8); 175 r->nb_sectors_abs = ldl_le_p(p + 12); 176 } 177 178 static int find_partition(BlockBackend *blk, int partition, 179 off_t *offset, off_t *size) 180 { 181 struct partition_record mbr[4]; 182 uint8_t data[MBR_SIZE]; 183 int i; 184 int ext_partnum = 4; 185 int ret; 186 187 ret = blk_pread(blk, 0, data, sizeof(data)); 188 if (ret < 0) { 189 error_report("error while reading: %s", strerror(-ret)); 190 exit(EXIT_FAILURE); 191 } 192 193 if (data[510] != 0x55 || data[511] != 0xaa) { 194 return -EINVAL; 195 } 196 197 for (i = 0; i < 4; i++) { 198 read_partition(&data[446 + 16 * i], &mbr[i]); 199 200 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 201 continue; 202 } 203 204 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 205 struct partition_record ext[4]; 206 uint8_t data1[MBR_SIZE]; 207 int j; 208 209 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, 210 data1, sizeof(data1)); 211 if (ret < 0) { 212 error_report("error while reading: %s", strerror(-ret)); 213 exit(EXIT_FAILURE); 214 } 215 216 for (j = 0; j < 4; j++) { 217 read_partition(&data1[446 + 16 * j], &ext[j]); 218 if (!ext[j].system || !ext[j].nb_sectors_abs) { 219 continue; 220 } 221 222 if ((ext_partnum + j + 1) == partition) { 223 *offset = (uint64_t)ext[j].start_sector_abs << 9; 224 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 225 return 0; 226 } 227 } 228 ext_partnum += 4; 229 } else if ((i + 1) == partition) { 230 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 231 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 232 return 0; 233 } 234 } 235 236 return -ENOENT; 237 } 238 239 static void termsig_handler(int signum) 240 { 241 atomic_cmpxchg(&state, RUNNING, TERMINATE); 242 qemu_notify_event(); 243 } 244 245 246 #if HAVE_NBD_DEVICE 247 static void *show_parts(void *arg) 248 { 249 char *device = arg; 250 int nbd; 251 252 /* linux just needs an open() to trigger 253 * the partition table update 254 * but remember to load the module with max_part != 0 : 255 * modprobe nbd max_part=63 256 */ 257 nbd = open(device, O_RDWR); 258 if (nbd >= 0) { 259 close(nbd); 260 } 261 return NULL; 262 } 263 264 static void *nbd_client_thread(void *arg) 265 { 266 char *device = arg; 267 NBDExportInfo info = { .request_sizes = false, }; 268 QIOChannelSocket *sioc; 269 int fd; 270 int ret; 271 pthread_t show_parts_thread; 272 Error *local_error = NULL; 273 274 sioc = qio_channel_socket_new(); 275 if (qio_channel_socket_connect_sync(sioc, 276 saddr, 277 &local_error) < 0) { 278 error_report_err(local_error); 279 goto out; 280 } 281 282 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, 283 NULL, NULL, NULL, &info, &local_error); 284 if (ret < 0) { 285 if (local_error) { 286 error_report_err(local_error); 287 } 288 goto out_socket; 289 } 290 291 fd = open(device, O_RDWR); 292 if (fd < 0) { 293 /* Linux-only, we can use %m in printf. */ 294 error_report("Failed to open %s: %m", device); 295 goto out_socket; 296 } 297 298 ret = nbd_init(fd, sioc, &info, &local_error); 299 if (ret < 0) { 300 error_report_err(local_error); 301 goto out_fd; 302 } 303 304 /* update partition table */ 305 pthread_create(&show_parts_thread, NULL, show_parts, device); 306 307 if (verbose) { 308 fprintf(stderr, "NBD device %s is now connected to %s\n", 309 device, srcpath); 310 } else { 311 /* Close stderr so that the qemu-nbd process exits. */ 312 dup2(STDOUT_FILENO, STDERR_FILENO); 313 } 314 315 ret = nbd_client(fd); 316 if (ret) { 317 goto out_fd; 318 } 319 close(fd); 320 object_unref(OBJECT(sioc)); 321 kill(getpid(), SIGTERM); 322 return (void *) EXIT_SUCCESS; 323 324 out_fd: 325 close(fd); 326 out_socket: 327 object_unref(OBJECT(sioc)); 328 out: 329 kill(getpid(), SIGTERM); 330 return (void *) EXIT_FAILURE; 331 } 332 #endif /* HAVE_NBD_DEVICE */ 333 334 static int nbd_can_accept(void) 335 { 336 return state == RUNNING && nb_fds < shared; 337 } 338 339 static void nbd_export_closed(NBDExport *export) 340 { 341 assert(state == TERMINATING); 342 state = TERMINATED; 343 } 344 345 static void nbd_update_server_watch(void); 346 347 static void nbd_client_closed(NBDClient *client, bool negotiated) 348 { 349 nb_fds--; 350 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 351 state = TERMINATE; 352 } 353 nbd_update_server_watch(); 354 nbd_client_put(client); 355 } 356 357 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 358 gpointer opaque) 359 { 360 if (state >= TERMINATE) { 361 return; 362 } 363 364 nb_fds++; 365 nbd_update_server_watch(); 366 nbd_client_new(cioc, tlscreds, NULL, nbd_client_closed); 367 } 368 369 static void nbd_update_server_watch(void) 370 { 371 if (nbd_can_accept()) { 372 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 373 } else { 374 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 375 } 376 } 377 378 379 static SocketAddress *nbd_build_socket_address(const char *sockpath, 380 const char *bindto, 381 const char *port) 382 { 383 SocketAddress *saddr; 384 385 saddr = g_new0(SocketAddress, 1); 386 if (sockpath) { 387 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 388 saddr->u.q_unix.path = g_strdup(sockpath); 389 } else { 390 InetSocketAddress *inet; 391 saddr->type = SOCKET_ADDRESS_TYPE_INET; 392 inet = &saddr->u.inet; 393 inet->host = g_strdup(bindto); 394 if (port) { 395 inet->port = g_strdup(port); 396 } else { 397 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 398 } 399 } 400 401 return saddr; 402 } 403 404 405 static QemuOptsList file_opts = { 406 .name = "file", 407 .implied_opt_name = "file", 408 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 409 .desc = { 410 /* no elements => accept any params */ 411 { /* end of list */ } 412 }, 413 }; 414 415 static QemuOptsList qemu_object_opts = { 416 .name = "object", 417 .implied_opt_name = "qom-type", 418 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 419 .desc = { 420 { } 421 }, 422 }; 423 424 425 426 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 427 { 428 Object *obj; 429 QCryptoTLSCreds *creds; 430 431 obj = object_resolve_path_component( 432 object_get_objects_root(), id); 433 if (!obj) { 434 error_setg(errp, "No TLS credentials with id '%s'", 435 id); 436 return NULL; 437 } 438 creds = (QCryptoTLSCreds *) 439 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 440 if (!creds) { 441 error_setg(errp, "Object with id '%s' is not TLS credentials", 442 id); 443 return NULL; 444 } 445 446 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 447 error_setg(errp, 448 "Expecting TLS credentials with a server endpoint"); 449 return NULL; 450 } 451 object_ref(obj); 452 return creds; 453 } 454 455 static void setup_address_and_port(const char **address, const char **port) 456 { 457 if (*address == NULL) { 458 *address = "0.0.0.0"; 459 } 460 461 if (*port == NULL) { 462 *port = stringify(NBD_DEFAULT_PORT); 463 } 464 } 465 466 /* 467 * Check socket parameters compatibility when socket activation is used. 468 */ 469 static const char *socket_activation_validate_opts(const char *device, 470 const char *sockpath, 471 const char *address, 472 const char *port) 473 { 474 if (device != NULL) { 475 return "NBD device can't be set when using socket activation"; 476 } 477 478 if (sockpath != NULL) { 479 return "Unix socket can't be set when using socket activation"; 480 } 481 482 if (address != NULL) { 483 return "The interface can't be set when using socket activation"; 484 } 485 486 if (port != NULL) { 487 return "TCP port number can't be set when using socket activation"; 488 } 489 490 return NULL; 491 } 492 493 static void qemu_nbd_shutdown(void) 494 { 495 job_cancel_sync_all(); 496 bdrv_close_all(); 497 } 498 499 int main(int argc, char **argv) 500 { 501 BlockBackend *blk; 502 BlockDriverState *bs; 503 off_t dev_offset = 0; 504 uint16_t nbdflags = 0; 505 bool disconnect = false; 506 const char *bindto = NULL; 507 const char *port = NULL; 508 char *sockpath = NULL; 509 char *device = NULL; 510 off_t fd_size; 511 QemuOpts *sn_opts = NULL; 512 const char *sn_id_or_name = NULL; 513 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:"; 514 struct option lopt[] = { 515 { "help", no_argument, NULL, 'h' }, 516 { "version", no_argument, NULL, 'V' }, 517 { "bind", required_argument, NULL, 'b' }, 518 { "port", required_argument, NULL, 'p' }, 519 { "socket", required_argument, NULL, 'k' }, 520 { "offset", required_argument, NULL, 'o' }, 521 { "read-only", no_argument, NULL, 'r' }, 522 { "partition", required_argument, NULL, 'P' }, 523 { "bitmap", required_argument, NULL, 'B' }, 524 { "connect", required_argument, NULL, 'c' }, 525 { "disconnect", no_argument, NULL, 'd' }, 526 { "snapshot", no_argument, NULL, 's' }, 527 { "load-snapshot", required_argument, NULL, 'l' }, 528 { "nocache", no_argument, NULL, 'n' }, 529 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 530 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 531 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 532 { "detect-zeroes", required_argument, NULL, 533 QEMU_NBD_OPT_DETECT_ZEROES }, 534 { "shared", required_argument, NULL, 'e' }, 535 { "format", required_argument, NULL, 'f' }, 536 { "persistent", no_argument, NULL, 't' }, 537 { "verbose", no_argument, NULL, 'v' }, 538 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 539 { "export-name", required_argument, NULL, 'x' }, 540 { "description", required_argument, NULL, 'D' }, 541 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 542 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 543 { "trace", required_argument, NULL, 'T' }, 544 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 545 { NULL, 0, NULL, 0 } 546 }; 547 int ch; 548 int opt_ind = 0; 549 char *end; 550 int flags = BDRV_O_RDWR; 551 int partition = -1; 552 int ret = 0; 553 bool seen_cache = false; 554 bool seen_discard = false; 555 bool seen_aio = false; 556 pthread_t client_thread; 557 const char *fmt = NULL; 558 Error *local_err = NULL; 559 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 560 QDict *options = NULL; 561 const char *export_name = ""; /* Default export name */ 562 const char *export_description = NULL; 563 const char *bitmap = NULL; 564 const char *tlscredsid = NULL; 565 bool imageOpts = false; 566 bool writethrough = true; 567 char *trace_file = NULL; 568 bool fork_process = false; 569 int old_stderr = -1; 570 unsigned socket_activation; 571 572 /* The client thread uses SIGTERM to interrupt the server. A signal 573 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 574 */ 575 struct sigaction sa_sigterm; 576 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 577 sa_sigterm.sa_handler = termsig_handler; 578 sigaction(SIGTERM, &sa_sigterm, NULL); 579 580 #ifdef CONFIG_POSIX 581 signal(SIGPIPE, SIG_IGN); 582 #endif 583 584 module_call_init(MODULE_INIT_TRACE); 585 error_set_progname(argv[0]); 586 qcrypto_init(&error_fatal); 587 588 module_call_init(MODULE_INIT_QOM); 589 qemu_add_opts(&qemu_object_opts); 590 qemu_add_opts(&qemu_trace_opts); 591 qemu_init_exec_dir(argv[0]); 592 593 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 594 switch (ch) { 595 case 's': 596 flags |= BDRV_O_SNAPSHOT; 597 break; 598 case 'n': 599 optarg = (char *) "none"; 600 /* fallthrough */ 601 case QEMU_NBD_OPT_CACHE: 602 if (seen_cache) { 603 error_report("-n and --cache can only be specified once"); 604 exit(EXIT_FAILURE); 605 } 606 seen_cache = true; 607 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 608 error_report("Invalid cache mode `%s'", optarg); 609 exit(EXIT_FAILURE); 610 } 611 break; 612 case QEMU_NBD_OPT_AIO: 613 if (seen_aio) { 614 error_report("--aio can only be specified once"); 615 exit(EXIT_FAILURE); 616 } 617 seen_aio = true; 618 if (!strcmp(optarg, "native")) { 619 flags |= BDRV_O_NATIVE_AIO; 620 } else if (!strcmp(optarg, "threads")) { 621 /* this is the default */ 622 } else { 623 error_report("invalid aio mode `%s'", optarg); 624 exit(EXIT_FAILURE); 625 } 626 break; 627 case QEMU_NBD_OPT_DISCARD: 628 if (seen_discard) { 629 error_report("--discard can only be specified once"); 630 exit(EXIT_FAILURE); 631 } 632 seen_discard = true; 633 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 634 error_report("Invalid discard mode `%s'", optarg); 635 exit(EXIT_FAILURE); 636 } 637 break; 638 case QEMU_NBD_OPT_DETECT_ZEROES: 639 detect_zeroes = 640 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 641 optarg, 642 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 643 &local_err); 644 if (local_err) { 645 error_reportf_err(local_err, 646 "Failed to parse detect_zeroes mode: "); 647 exit(EXIT_FAILURE); 648 } 649 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 650 !(flags & BDRV_O_UNMAP)) { 651 error_report("setting detect-zeroes to unmap is not allowed " 652 "without setting discard operation to unmap"); 653 exit(EXIT_FAILURE); 654 } 655 break; 656 case 'b': 657 bindto = optarg; 658 break; 659 case 'p': 660 port = optarg; 661 break; 662 case 'o': 663 dev_offset = strtoll (optarg, &end, 0); 664 if (*end) { 665 error_report("Invalid offset `%s'", optarg); 666 exit(EXIT_FAILURE); 667 } 668 if (dev_offset < 0) { 669 error_report("Offset must be positive `%s'", optarg); 670 exit(EXIT_FAILURE); 671 } 672 break; 673 case 'l': 674 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 675 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 676 optarg, false); 677 if (!sn_opts) { 678 error_report("Failed in parsing snapshot param `%s'", 679 optarg); 680 exit(EXIT_FAILURE); 681 } 682 } else { 683 sn_id_or_name = optarg; 684 } 685 /* fall through */ 686 case 'r': 687 nbdflags |= NBD_FLAG_READ_ONLY; 688 flags &= ~BDRV_O_RDWR; 689 break; 690 case 'P': 691 partition = strtol(optarg, &end, 0); 692 if (*end) { 693 error_report("Invalid partition `%s'", optarg); 694 exit(EXIT_FAILURE); 695 } 696 if (partition < 1 || partition > 8) { 697 error_report("Invalid partition %d", partition); 698 exit(EXIT_FAILURE); 699 } 700 break; 701 case 'B': 702 bitmap = optarg; 703 break; 704 case 'k': 705 sockpath = optarg; 706 if (sockpath[0] != '/') { 707 error_report("socket path must be absolute"); 708 exit(EXIT_FAILURE); 709 } 710 break; 711 case 'd': 712 disconnect = true; 713 break; 714 case 'c': 715 device = optarg; 716 break; 717 case 'e': 718 shared = strtol(optarg, &end, 0); 719 if (*end) { 720 error_report("Invalid shared device number '%s'", optarg); 721 exit(EXIT_FAILURE); 722 } 723 if (shared < 1) { 724 error_report("Shared device number must be greater than 0"); 725 exit(EXIT_FAILURE); 726 } 727 break; 728 case 'f': 729 fmt = optarg; 730 break; 731 case 't': 732 persistent = 1; 733 break; 734 case 'x': 735 export_name = optarg; 736 break; 737 case 'D': 738 export_description = optarg; 739 break; 740 case 'v': 741 verbose = 1; 742 break; 743 case 'V': 744 version(argv[0]); 745 exit(0); 746 break; 747 case 'h': 748 usage(argv[0]); 749 exit(0); 750 break; 751 case '?': 752 error_report("Try `%s --help' for more information.", argv[0]); 753 exit(EXIT_FAILURE); 754 case QEMU_NBD_OPT_OBJECT: { 755 QemuOpts *opts; 756 opts = qemu_opts_parse_noisily(&qemu_object_opts, 757 optarg, true); 758 if (!opts) { 759 exit(EXIT_FAILURE); 760 } 761 } break; 762 case QEMU_NBD_OPT_TLSCREDS: 763 tlscredsid = optarg; 764 break; 765 case QEMU_NBD_OPT_IMAGE_OPTS: 766 imageOpts = true; 767 break; 768 case 'T': 769 g_free(trace_file); 770 trace_file = trace_opt_parse(optarg); 771 break; 772 case QEMU_NBD_OPT_FORK: 773 fork_process = true; 774 break; 775 } 776 } 777 778 if ((argc - optind) != 1) { 779 error_report("Invalid number of arguments"); 780 error_printf("Try `%s --help' for more information.\n", argv[0]); 781 exit(EXIT_FAILURE); 782 } 783 784 qemu_opts_foreach(&qemu_object_opts, 785 user_creatable_add_opts_foreach, 786 NULL, &error_fatal); 787 788 if (!trace_init_backends()) { 789 exit(1); 790 } 791 trace_init_file(trace_file); 792 qemu_set_log(LOG_TRACE); 793 794 socket_activation = check_socket_activation(); 795 if (socket_activation == 0) { 796 setup_address_and_port(&bindto, &port); 797 } else { 798 /* Using socket activation - check user didn't use -p etc. */ 799 const char *err_msg = socket_activation_validate_opts(device, sockpath, 800 bindto, port); 801 if (err_msg != NULL) { 802 error_report("%s", err_msg); 803 exit(EXIT_FAILURE); 804 } 805 806 /* qemu-nbd can only listen on a single socket. */ 807 if (socket_activation > 1) { 808 error_report("qemu-nbd does not support socket activation with %s > 1", 809 "LISTEN_FDS"); 810 exit(EXIT_FAILURE); 811 } 812 } 813 814 if (tlscredsid) { 815 if (sockpath) { 816 error_report("TLS is only supported with IPv4/IPv6"); 817 exit(EXIT_FAILURE); 818 } 819 if (device) { 820 error_report("TLS is not supported with a host device"); 821 exit(EXIT_FAILURE); 822 } 823 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 824 if (local_err) { 825 error_report("Failed to get TLS creds %s", 826 error_get_pretty(local_err)); 827 exit(EXIT_FAILURE); 828 } 829 } 830 831 #if !HAVE_NBD_DEVICE 832 if (disconnect || device) { 833 error_report("Kernel /dev/nbdN support not available"); 834 exit(EXIT_FAILURE); 835 } 836 #else /* HAVE_NBD_DEVICE */ 837 if (disconnect) { 838 int nbdfd = open(argv[optind], O_RDWR); 839 if (nbdfd < 0) { 840 error_report("Cannot open %s: %s", argv[optind], 841 strerror(errno)); 842 exit(EXIT_FAILURE); 843 } 844 nbd_disconnect(nbdfd); 845 846 close(nbdfd); 847 848 printf("%s disconnected\n", argv[optind]); 849 850 return 0; 851 } 852 #endif 853 854 if ((device && !verbose) || fork_process) { 855 int stderr_fd[2]; 856 pid_t pid; 857 int ret; 858 859 if (qemu_pipe(stderr_fd) < 0) { 860 error_report("Error setting up communication pipe: %s", 861 strerror(errno)); 862 exit(EXIT_FAILURE); 863 } 864 865 /* Now daemonize, but keep a communication channel open to 866 * print errors and exit with the proper status code. 867 */ 868 pid = fork(); 869 if (pid < 0) { 870 error_report("Failed to fork: %s", strerror(errno)); 871 exit(EXIT_FAILURE); 872 } else if (pid == 0) { 873 close(stderr_fd[0]); 874 ret = qemu_daemon(1, 0); 875 876 /* Temporarily redirect stderr to the parent's pipe... */ 877 old_stderr = dup(STDERR_FILENO); 878 dup2(stderr_fd[1], STDERR_FILENO); 879 if (ret < 0) { 880 error_report("Failed to daemonize: %s", strerror(errno)); 881 exit(EXIT_FAILURE); 882 } 883 884 /* ... close the descriptor we inherited and go on. */ 885 close(stderr_fd[1]); 886 } else { 887 bool errors = false; 888 char *buf; 889 890 /* In the parent. Print error messages from the child until 891 * it closes the pipe. 892 */ 893 close(stderr_fd[1]); 894 buf = g_malloc(1024); 895 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 896 errors = true; 897 ret = qemu_write_full(STDERR_FILENO, buf, ret); 898 if (ret < 0) { 899 exit(EXIT_FAILURE); 900 } 901 } 902 if (ret < 0) { 903 error_report("Cannot read from daemon: %s", 904 strerror(errno)); 905 exit(EXIT_FAILURE); 906 } 907 908 /* Usually the daemon should not print any message. 909 * Exit with zero status in that case. 910 */ 911 exit(errors); 912 } 913 } 914 915 if (device != NULL && sockpath == NULL) { 916 sockpath = g_malloc(128); 917 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 918 } 919 920 server = qio_net_listener_new(); 921 if (socket_activation == 0) { 922 saddr = nbd_build_socket_address(sockpath, bindto, port); 923 if (qio_net_listener_open_sync(server, saddr, &local_err) < 0) { 924 object_unref(OBJECT(server)); 925 error_report_err(local_err); 926 exit(EXIT_FAILURE); 927 } 928 } else { 929 size_t i; 930 /* See comment in check_socket_activation above. */ 931 for (i = 0; i < socket_activation; i++) { 932 QIOChannelSocket *sioc; 933 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 934 &local_err); 935 if (sioc == NULL) { 936 object_unref(OBJECT(server)); 937 error_report("Failed to use socket activation: %s", 938 error_get_pretty(local_err)); 939 exit(EXIT_FAILURE); 940 } 941 qio_net_listener_add(server, sioc); 942 object_unref(OBJECT(sioc)); 943 } 944 } 945 946 if (qemu_init_main_loop(&local_err)) { 947 error_report_err(local_err); 948 exit(EXIT_FAILURE); 949 } 950 bdrv_init(); 951 atexit(qemu_nbd_shutdown); 952 953 srcpath = argv[optind]; 954 if (imageOpts) { 955 QemuOpts *opts; 956 if (fmt) { 957 error_report("--image-opts and -f are mutually exclusive"); 958 exit(EXIT_FAILURE); 959 } 960 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 961 if (!opts) { 962 qemu_opts_reset(&file_opts); 963 exit(EXIT_FAILURE); 964 } 965 options = qemu_opts_to_qdict(opts, NULL); 966 qemu_opts_reset(&file_opts); 967 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 968 } else { 969 if (fmt) { 970 options = qdict_new(); 971 qdict_put_str(options, "driver", fmt); 972 } 973 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 974 } 975 976 if (!blk) { 977 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 978 argv[optind]); 979 exit(EXIT_FAILURE); 980 } 981 bs = blk_bs(blk); 982 983 blk_set_enable_write_cache(blk, !writethrough); 984 985 if (sn_opts) { 986 ret = bdrv_snapshot_load_tmp(bs, 987 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 988 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 989 &local_err); 990 } else if (sn_id_or_name) { 991 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 992 &local_err); 993 } 994 if (ret < 0) { 995 error_reportf_err(local_err, "Failed to load snapshot: "); 996 exit(EXIT_FAILURE); 997 } 998 999 bs->detect_zeroes = detect_zeroes; 1000 fd_size = blk_getlength(blk); 1001 if (fd_size < 0) { 1002 error_report("Failed to determine the image length: %s", 1003 strerror(-fd_size)); 1004 exit(EXIT_FAILURE); 1005 } 1006 1007 if (dev_offset >= fd_size) { 1008 error_report("Offset (%lld) has to be smaller than the image size " 1009 "(%lld)", 1010 (long long int)dev_offset, (long long int)fd_size); 1011 exit(EXIT_FAILURE); 1012 } 1013 fd_size -= dev_offset; 1014 1015 if (partition != -1) { 1016 ret = find_partition(blk, partition, &dev_offset, &fd_size); 1017 if (ret < 0) { 1018 error_report("Could not find partition %d: %s", partition, 1019 strerror(-ret)); 1020 exit(EXIT_FAILURE); 1021 } 1022 } 1023 1024 export = nbd_export_new(bs, dev_offset, fd_size, export_name, 1025 export_description, bitmap, nbdflags, 1026 nbd_export_closed, writethrough, NULL, 1027 &error_fatal); 1028 1029 if (device) { 1030 #if HAVE_NBD_DEVICE 1031 int ret; 1032 1033 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1034 if (ret != 0) { 1035 error_report("Failed to create client thread: %s", strerror(ret)); 1036 exit(EXIT_FAILURE); 1037 } 1038 #endif 1039 } else { 1040 /* Shut up GCC warnings. */ 1041 memset(&client_thread, 0, sizeof(client_thread)); 1042 } 1043 1044 nbd_update_server_watch(); 1045 1046 /* now when the initialization is (almost) complete, chdir("/") 1047 * to free any busy filesystems */ 1048 if (chdir("/") < 0) { 1049 error_report("Could not chdir to root directory: %s", 1050 strerror(errno)); 1051 exit(EXIT_FAILURE); 1052 } 1053 1054 if (fork_process) { 1055 dup2(old_stderr, STDERR_FILENO); 1056 close(old_stderr); 1057 } 1058 1059 state = RUNNING; 1060 do { 1061 main_loop_wait(false); 1062 if (state == TERMINATE) { 1063 state = TERMINATING; 1064 nbd_export_close(export); 1065 nbd_export_put(export); 1066 export = NULL; 1067 } 1068 } while (state != TERMINATED); 1069 1070 blk_unref(blk); 1071 if (sockpath) { 1072 unlink(sockpath); 1073 } 1074 1075 qemu_opts_del(sn_opts); 1076 1077 if (device) { 1078 void *ret; 1079 pthread_join(client_thread, &ret); 1080 exit(ret != NULL); 1081 } else { 1082 exit(EXIT_SUCCESS); 1083 } 1084 } 1085