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 "qapi/error.h" 21 #include "qemu-common.h" 22 #include "qemu/cutils.h" 23 #include "sysemu/block-backend.h" 24 #include "block/block_int.h" 25 #include "block/nbd.h" 26 #include "qemu/main-loop.h" 27 #include "qemu/error-report.h" 28 #include "qemu/config-file.h" 29 #include "qemu/bswap.h" 30 #include "qemu/log.h" 31 #include "block/snapshot.h" 32 #include "qapi/util.h" 33 #include "qapi/qmp/qstring.h" 34 #include "qom/object_interfaces.h" 35 #include "io/channel-socket.h" 36 #include "crypto/init.h" 37 #include "trace/control.h" 38 39 #include <getopt.h> 40 #include <libgen.h> 41 #include <pthread.h> 42 43 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 44 #define QEMU_NBD_OPT_CACHE 256 45 #define QEMU_NBD_OPT_AIO 257 46 #define QEMU_NBD_OPT_DISCARD 258 47 #define QEMU_NBD_OPT_DETECT_ZEROES 259 48 #define QEMU_NBD_OPT_OBJECT 260 49 #define QEMU_NBD_OPT_TLSCREDS 261 50 #define QEMU_NBD_OPT_IMAGE_OPTS 262 51 #define QEMU_NBD_OPT_FORK 263 52 53 #define MBR_SIZE 512 54 55 static NBDExport *exp; 56 static bool newproto; 57 static int verbose; 58 static char *srcpath; 59 static SocketAddress *saddr; 60 static int persistent = 0; 61 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 62 static int shared = 1; 63 static int nb_fds; 64 static QIOChannelSocket *server_ioc; 65 static int server_watch = -1; 66 static QCryptoTLSCreds *tlscreds; 67 68 static void usage(const char *name) 69 { 70 (printf) ( 71 "Usage: %s [OPTIONS] FILE\n" 72 "QEMU Disk Network Block Device Server\n" 73 "\n" 74 " -h, --help display this help and exit\n" 75 " -V, --version output version information and exit\n" 76 "\n" 77 "Connection properties:\n" 78 " -p, --port=PORT port to listen on (default `%d')\n" 79 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 80 " -k, --socket=PATH path to the unix socket\n" 81 " (default '"SOCKET_PATH"')\n" 82 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 83 " -t, --persistent don't exit on the last connection\n" 84 " -v, --verbose display extra debugging information\n" 85 " -x, --export-name=NAME expose export by name\n" 86 "\n" 87 "Exposing part of the image:\n" 88 " -o, --offset=OFFSET offset into the image\n" 89 " -P, --partition=NUM only expose partition NUM\n" 90 "\n" 91 "General purpose options:\n" 92 " --object type,id=ID,... define an object such as 'secret' for providing\n" 93 " passwords and/or encryption keys\n" 94 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 95 " specify tracing options\n" 96 " --fork fork off the server process and exit the parent\n" 97 " once the server is running\n" 98 #ifdef __linux__ 99 "Kernel NBD client support:\n" 100 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 101 " -d, --disconnect disconnect the specified device\n" 102 "\n" 103 #endif 104 "\n" 105 "Block device options:\n" 106 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 107 " -r, --read-only export read-only\n" 108 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 109 " file with backing_file=FILE, redirect the write to\n" 110 " the temporary one\n" 111 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 112 " load an internal snapshot inside FILE and export it\n" 113 " as an read-only device, SNAPSHOT_PARAM format is\n" 114 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 115 " '[ID_OR_NAME]'\n" 116 " -n, --nocache disable host cache\n" 117 " --cache=MODE set cache mode (none, writeback, ...)\n" 118 " --aio=MODE set AIO mode (native or threads)\n" 119 " --discard=MODE set discard mode (ignore, unmap)\n" 120 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 121 " --image-opts treat FILE as a full set of image options\n" 122 "\n" 123 "Report bugs to <qemu-devel@nongnu.org>\n" 124 , name, NBD_DEFAULT_PORT, "DEVICE"); 125 } 126 127 static void version(const char *name) 128 { 129 printf( 130 "%s version 0.0.1\n" 131 "Written by Anthony Liguori.\n" 132 "\n" 133 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n" 134 "This is free software; see the source for copying conditions. There is NO\n" 135 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 136 , name); 137 } 138 139 struct partition_record 140 { 141 uint8_t bootable; 142 uint8_t start_head; 143 uint32_t start_cylinder; 144 uint8_t start_sector; 145 uint8_t system; 146 uint8_t end_head; 147 uint8_t end_cylinder; 148 uint8_t end_sector; 149 uint32_t start_sector_abs; 150 uint32_t nb_sectors_abs; 151 }; 152 153 static void read_partition(uint8_t *p, struct partition_record *r) 154 { 155 r->bootable = p[0]; 156 r->start_head = p[1]; 157 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 158 r->start_sector = p[2] & 0x3f; 159 r->system = p[4]; 160 r->end_head = p[5]; 161 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 162 r->end_sector = p[6] & 0x3f; 163 164 r->start_sector_abs = ldl_le_p(p + 8); 165 r->nb_sectors_abs = ldl_le_p(p + 12); 166 } 167 168 static int find_partition(BlockBackend *blk, int partition, 169 off_t *offset, off_t *size) 170 { 171 struct partition_record mbr[4]; 172 uint8_t data[MBR_SIZE]; 173 int i; 174 int ext_partnum = 4; 175 int ret; 176 177 ret = blk_pread(blk, 0, data, sizeof(data)); 178 if (ret < 0) { 179 error_report("error while reading: %s", strerror(-ret)); 180 exit(EXIT_FAILURE); 181 } 182 183 if (data[510] != 0x55 || data[511] != 0xaa) { 184 return -EINVAL; 185 } 186 187 for (i = 0; i < 4; i++) { 188 read_partition(&data[446 + 16 * i], &mbr[i]); 189 190 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 191 continue; 192 } 193 194 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 195 struct partition_record ext[4]; 196 uint8_t data1[MBR_SIZE]; 197 int j; 198 199 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, 200 data1, sizeof(data1)); 201 if (ret < 0) { 202 error_report("error while reading: %s", strerror(-ret)); 203 exit(EXIT_FAILURE); 204 } 205 206 for (j = 0; j < 4; j++) { 207 read_partition(&data1[446 + 16 * j], &ext[j]); 208 if (!ext[j].system || !ext[j].nb_sectors_abs) { 209 continue; 210 } 211 212 if ((ext_partnum + j + 1) == partition) { 213 *offset = (uint64_t)ext[j].start_sector_abs << 9; 214 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 215 return 0; 216 } 217 } 218 ext_partnum += 4; 219 } else if ((i + 1) == partition) { 220 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 221 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 222 return 0; 223 } 224 } 225 226 return -ENOENT; 227 } 228 229 static void termsig_handler(int signum) 230 { 231 atomic_cmpxchg(&state, RUNNING, TERMINATE); 232 qemu_notify_event(); 233 } 234 235 236 static void *show_parts(void *arg) 237 { 238 char *device = arg; 239 int nbd; 240 241 /* linux just needs an open() to trigger 242 * the partition table update 243 * but remember to load the module with max_part != 0 : 244 * modprobe nbd max_part=63 245 */ 246 nbd = open(device, O_RDWR); 247 if (nbd >= 0) { 248 close(nbd); 249 } 250 return NULL; 251 } 252 253 static void *nbd_client_thread(void *arg) 254 { 255 char *device = arg; 256 off_t size; 257 uint16_t nbdflags; 258 QIOChannelSocket *sioc; 259 int fd; 260 int ret; 261 pthread_t show_parts_thread; 262 Error *local_error = NULL; 263 264 sioc = qio_channel_socket_new(); 265 if (qio_channel_socket_connect_sync(sioc, 266 saddr, 267 &local_error) < 0) { 268 error_report_err(local_error); 269 goto out; 270 } 271 272 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, &nbdflags, 273 NULL, NULL, NULL, 274 &size, &local_error); 275 if (ret < 0) { 276 if (local_error) { 277 error_report_err(local_error); 278 } 279 goto out_socket; 280 } 281 282 fd = open(device, O_RDWR); 283 if (fd < 0) { 284 /* Linux-only, we can use %m in printf. */ 285 error_report("Failed to open %s: %m", device); 286 goto out_socket; 287 } 288 289 ret = nbd_init(fd, sioc, nbdflags, size); 290 if (ret < 0) { 291 goto out_fd; 292 } 293 294 /* update partition table */ 295 pthread_create(&show_parts_thread, NULL, show_parts, device); 296 297 if (verbose) { 298 fprintf(stderr, "NBD device %s is now connected to %s\n", 299 device, srcpath); 300 } else { 301 /* Close stderr so that the qemu-nbd process exits. */ 302 dup2(STDOUT_FILENO, STDERR_FILENO); 303 } 304 305 ret = nbd_client(fd); 306 if (ret) { 307 goto out_fd; 308 } 309 close(fd); 310 object_unref(OBJECT(sioc)); 311 kill(getpid(), SIGTERM); 312 return (void *) EXIT_SUCCESS; 313 314 out_fd: 315 close(fd); 316 out_socket: 317 object_unref(OBJECT(sioc)); 318 out: 319 kill(getpid(), SIGTERM); 320 return (void *) EXIT_FAILURE; 321 } 322 323 static int nbd_can_accept(void) 324 { 325 return nb_fds < shared; 326 } 327 328 static void nbd_export_closed(NBDExport *exp) 329 { 330 assert(state == TERMINATING); 331 state = TERMINATED; 332 } 333 334 static void nbd_update_server_watch(void); 335 336 static void nbd_client_closed(NBDClient *client) 337 { 338 nb_fds--; 339 if (nb_fds == 0 && !persistent && state == RUNNING) { 340 state = TERMINATE; 341 } 342 nbd_update_server_watch(); 343 nbd_client_put(client); 344 } 345 346 static gboolean nbd_accept(QIOChannel *ioc, GIOCondition cond, gpointer opaque) 347 { 348 QIOChannelSocket *cioc; 349 350 cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc), 351 NULL); 352 if (!cioc) { 353 return TRUE; 354 } 355 356 if (state >= TERMINATE) { 357 object_unref(OBJECT(cioc)); 358 return TRUE; 359 } 360 361 nb_fds++; 362 nbd_update_server_watch(); 363 nbd_client_new(newproto ? NULL : exp, cioc, 364 tlscreds, NULL, nbd_client_closed); 365 object_unref(OBJECT(cioc)); 366 367 return TRUE; 368 } 369 370 static void nbd_update_server_watch(void) 371 { 372 if (nbd_can_accept()) { 373 if (server_watch == -1) { 374 server_watch = qio_channel_add_watch(QIO_CHANNEL(server_ioc), 375 G_IO_IN, 376 nbd_accept, 377 NULL, NULL); 378 } 379 } else { 380 if (server_watch != -1) { 381 g_source_remove(server_watch); 382 server_watch = -1; 383 } 384 } 385 } 386 387 388 static SocketAddress *nbd_build_socket_address(const char *sockpath, 389 const char *bindto, 390 const char *port) 391 { 392 SocketAddress *saddr; 393 394 saddr = g_new0(SocketAddress, 1); 395 if (sockpath) { 396 saddr->type = SOCKET_ADDRESS_KIND_UNIX; 397 saddr->u.q_unix.data = g_new0(UnixSocketAddress, 1); 398 saddr->u.q_unix.data->path = g_strdup(sockpath); 399 } else { 400 InetSocketAddress *inet; 401 saddr->type = SOCKET_ADDRESS_KIND_INET; 402 inet = saddr->u.inet.data = g_new0(InetSocketAddress, 1); 403 inet->host = g_strdup(bindto); 404 if (port) { 405 inet->port = g_strdup(port); 406 } else { 407 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 408 } 409 } 410 411 return saddr; 412 } 413 414 415 static QemuOptsList file_opts = { 416 .name = "file", 417 .implied_opt_name = "file", 418 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 419 .desc = { 420 /* no elements => accept any params */ 421 { /* end of list */ } 422 }, 423 }; 424 425 static QemuOptsList qemu_object_opts = { 426 .name = "object", 427 .implied_opt_name = "qom-type", 428 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 429 .desc = { 430 { } 431 }, 432 }; 433 434 435 436 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 437 { 438 Object *obj; 439 QCryptoTLSCreds *creds; 440 441 obj = object_resolve_path_component( 442 object_get_objects_root(), id); 443 if (!obj) { 444 error_setg(errp, "No TLS credentials with id '%s'", 445 id); 446 return NULL; 447 } 448 creds = (QCryptoTLSCreds *) 449 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 450 if (!creds) { 451 error_setg(errp, "Object with id '%s' is not TLS credentials", 452 id); 453 return NULL; 454 } 455 456 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 457 error_setg(errp, 458 "Expecting TLS credentials with a server endpoint"); 459 return NULL; 460 } 461 object_ref(obj); 462 return creds; 463 } 464 465 466 int main(int argc, char **argv) 467 { 468 BlockBackend *blk; 469 BlockDriverState *bs; 470 off_t dev_offset = 0; 471 uint16_t nbdflags = 0; 472 bool disconnect = false; 473 const char *bindto = "0.0.0.0"; 474 const char *port = NULL; 475 char *sockpath = NULL; 476 char *device = NULL; 477 off_t fd_size; 478 QemuOpts *sn_opts = NULL; 479 const char *sn_id_or_name = NULL; 480 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:"; 481 struct option lopt[] = { 482 { "help", no_argument, NULL, 'h' }, 483 { "version", no_argument, NULL, 'V' }, 484 { "bind", required_argument, NULL, 'b' }, 485 { "port", required_argument, NULL, 'p' }, 486 { "socket", required_argument, NULL, 'k' }, 487 { "offset", required_argument, NULL, 'o' }, 488 { "read-only", no_argument, NULL, 'r' }, 489 { "partition", required_argument, NULL, 'P' }, 490 { "connect", required_argument, NULL, 'c' }, 491 { "disconnect", no_argument, NULL, 'd' }, 492 { "snapshot", no_argument, NULL, 's' }, 493 { "load-snapshot", required_argument, NULL, 'l' }, 494 { "nocache", no_argument, NULL, 'n' }, 495 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 496 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 497 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 498 { "detect-zeroes", required_argument, NULL, 499 QEMU_NBD_OPT_DETECT_ZEROES }, 500 { "shared", required_argument, NULL, 'e' }, 501 { "format", required_argument, NULL, 'f' }, 502 { "persistent", no_argument, NULL, 't' }, 503 { "verbose", no_argument, NULL, 'v' }, 504 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 505 { "export-name", required_argument, NULL, 'x' }, 506 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 507 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 508 { "trace", required_argument, NULL, 'T' }, 509 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 510 { NULL, 0, NULL, 0 } 511 }; 512 int ch; 513 int opt_ind = 0; 514 char *end; 515 int flags = BDRV_O_RDWR; 516 int partition = -1; 517 int ret = 0; 518 bool seen_cache = false; 519 bool seen_discard = false; 520 bool seen_aio = false; 521 pthread_t client_thread; 522 const char *fmt = NULL; 523 Error *local_err = NULL; 524 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 525 QDict *options = NULL; 526 const char *export_name = NULL; 527 const char *tlscredsid = NULL; 528 bool imageOpts = false; 529 bool writethrough = true; 530 char *trace_file = NULL; 531 bool fork_process = false; 532 int old_stderr = -1; 533 534 /* The client thread uses SIGTERM to interrupt the server. A signal 535 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 536 */ 537 struct sigaction sa_sigterm; 538 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 539 sa_sigterm.sa_handler = termsig_handler; 540 sigaction(SIGTERM, &sa_sigterm, NULL); 541 542 module_call_init(MODULE_INIT_TRACE); 543 qcrypto_init(&error_fatal); 544 545 module_call_init(MODULE_INIT_QOM); 546 qemu_add_opts(&qemu_object_opts); 547 qemu_add_opts(&qemu_trace_opts); 548 qemu_init_exec_dir(argv[0]); 549 550 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 551 switch (ch) { 552 case 's': 553 flags |= BDRV_O_SNAPSHOT; 554 break; 555 case 'n': 556 optarg = (char *) "none"; 557 /* fallthrough */ 558 case QEMU_NBD_OPT_CACHE: 559 if (seen_cache) { 560 error_report("-n and --cache can only be specified once"); 561 exit(EXIT_FAILURE); 562 } 563 seen_cache = true; 564 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 565 error_report("Invalid cache mode `%s'", optarg); 566 exit(EXIT_FAILURE); 567 } 568 break; 569 case QEMU_NBD_OPT_AIO: 570 if (seen_aio) { 571 error_report("--aio can only be specified once"); 572 exit(EXIT_FAILURE); 573 } 574 seen_aio = true; 575 if (!strcmp(optarg, "native")) { 576 flags |= BDRV_O_NATIVE_AIO; 577 } else if (!strcmp(optarg, "threads")) { 578 /* this is the default */ 579 } else { 580 error_report("invalid aio mode `%s'", optarg); 581 exit(EXIT_FAILURE); 582 } 583 break; 584 case QEMU_NBD_OPT_DISCARD: 585 if (seen_discard) { 586 error_report("--discard can only be specified once"); 587 exit(EXIT_FAILURE); 588 } 589 seen_discard = true; 590 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 591 error_report("Invalid discard mode `%s'", optarg); 592 exit(EXIT_FAILURE); 593 } 594 break; 595 case QEMU_NBD_OPT_DETECT_ZEROES: 596 detect_zeroes = 597 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 598 optarg, 599 BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX, 600 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 601 &local_err); 602 if (local_err) { 603 error_reportf_err(local_err, 604 "Failed to parse detect_zeroes mode: "); 605 exit(EXIT_FAILURE); 606 } 607 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 608 !(flags & BDRV_O_UNMAP)) { 609 error_report("setting detect-zeroes to unmap is not allowed " 610 "without setting discard operation to unmap"); 611 exit(EXIT_FAILURE); 612 } 613 break; 614 case 'b': 615 bindto = optarg; 616 break; 617 case 'p': 618 port = optarg; 619 break; 620 case 'o': 621 dev_offset = strtoll (optarg, &end, 0); 622 if (*end) { 623 error_report("Invalid offset `%s'", optarg); 624 exit(EXIT_FAILURE); 625 } 626 if (dev_offset < 0) { 627 error_report("Offset must be positive `%s'", optarg); 628 exit(EXIT_FAILURE); 629 } 630 break; 631 case 'l': 632 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 633 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 634 optarg, false); 635 if (!sn_opts) { 636 error_report("Failed in parsing snapshot param `%s'", 637 optarg); 638 exit(EXIT_FAILURE); 639 } 640 } else { 641 sn_id_or_name = optarg; 642 } 643 /* fall through */ 644 case 'r': 645 nbdflags |= NBD_FLAG_READ_ONLY; 646 flags &= ~BDRV_O_RDWR; 647 break; 648 case 'P': 649 partition = strtol(optarg, &end, 0); 650 if (*end) { 651 error_report("Invalid partition `%s'", optarg); 652 exit(EXIT_FAILURE); 653 } 654 if (partition < 1 || partition > 8) { 655 error_report("Invalid partition %d", partition); 656 exit(EXIT_FAILURE); 657 } 658 break; 659 case 'k': 660 sockpath = optarg; 661 if (sockpath[0] != '/') { 662 error_report("socket path must be absolute"); 663 exit(EXIT_FAILURE); 664 } 665 break; 666 case 'd': 667 disconnect = true; 668 break; 669 case 'c': 670 device = optarg; 671 break; 672 case 'e': 673 shared = strtol(optarg, &end, 0); 674 if (*end) { 675 error_report("Invalid shared device number '%s'", optarg); 676 exit(EXIT_FAILURE); 677 } 678 if (shared < 1) { 679 error_report("Shared device number must be greater than 0"); 680 exit(EXIT_FAILURE); 681 } 682 break; 683 case 'f': 684 fmt = optarg; 685 break; 686 case 't': 687 persistent = 1; 688 break; 689 case 'x': 690 export_name = optarg; 691 break; 692 case 'v': 693 verbose = 1; 694 break; 695 case 'V': 696 version(argv[0]); 697 exit(0); 698 break; 699 case 'h': 700 usage(argv[0]); 701 exit(0); 702 break; 703 case '?': 704 error_report("Try `%s --help' for more information.", argv[0]); 705 exit(EXIT_FAILURE); 706 case QEMU_NBD_OPT_OBJECT: { 707 QemuOpts *opts; 708 opts = qemu_opts_parse_noisily(&qemu_object_opts, 709 optarg, true); 710 if (!opts) { 711 exit(EXIT_FAILURE); 712 } 713 } break; 714 case QEMU_NBD_OPT_TLSCREDS: 715 tlscredsid = optarg; 716 break; 717 case QEMU_NBD_OPT_IMAGE_OPTS: 718 imageOpts = true; 719 break; 720 case 'T': 721 g_free(trace_file); 722 trace_file = trace_opt_parse(optarg); 723 break; 724 case QEMU_NBD_OPT_FORK: 725 fork_process = true; 726 break; 727 } 728 } 729 730 if ((argc - optind) != 1) { 731 error_report("Invalid number of arguments"); 732 error_printf("Try `%s --help' for more information.\n", argv[0]); 733 exit(EXIT_FAILURE); 734 } 735 736 if (qemu_opts_foreach(&qemu_object_opts, 737 user_creatable_add_opts_foreach, 738 NULL, NULL)) { 739 exit(EXIT_FAILURE); 740 } 741 742 if (!trace_init_backends()) { 743 exit(1); 744 } 745 trace_init_file(trace_file); 746 qemu_set_log(LOG_TRACE); 747 748 if (tlscredsid) { 749 if (sockpath) { 750 error_report("TLS is only supported with IPv4/IPv6"); 751 exit(EXIT_FAILURE); 752 } 753 if (device) { 754 error_report("TLS is not supported with a host device"); 755 exit(EXIT_FAILURE); 756 } 757 if (!export_name) { 758 /* Set the default NBD protocol export name, since 759 * we *must* use new style protocol for TLS */ 760 export_name = ""; 761 } 762 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 763 if (local_err) { 764 error_report("Failed to get TLS creds %s", 765 error_get_pretty(local_err)); 766 exit(EXIT_FAILURE); 767 } 768 } 769 770 if (disconnect) { 771 int nbdfd = open(argv[optind], O_RDWR); 772 if (nbdfd < 0) { 773 error_report("Cannot open %s: %s", argv[optind], 774 strerror(errno)); 775 exit(EXIT_FAILURE); 776 } 777 nbd_disconnect(nbdfd); 778 779 close(nbdfd); 780 781 printf("%s disconnected\n", argv[optind]); 782 783 return 0; 784 } 785 786 if ((device && !verbose) || fork_process) { 787 int stderr_fd[2]; 788 pid_t pid; 789 int ret; 790 791 if (qemu_pipe(stderr_fd) < 0) { 792 error_report("Error setting up communication pipe: %s", 793 strerror(errno)); 794 exit(EXIT_FAILURE); 795 } 796 797 /* Now daemonize, but keep a communication channel open to 798 * print errors and exit with the proper status code. 799 */ 800 pid = fork(); 801 if (pid < 0) { 802 error_report("Failed to fork: %s", strerror(errno)); 803 exit(EXIT_FAILURE); 804 } else if (pid == 0) { 805 close(stderr_fd[0]); 806 ret = qemu_daemon(1, 0); 807 808 /* Temporarily redirect stderr to the parent's pipe... */ 809 old_stderr = dup(STDERR_FILENO); 810 dup2(stderr_fd[1], STDERR_FILENO); 811 if (ret < 0) { 812 error_report("Failed to daemonize: %s", strerror(errno)); 813 exit(EXIT_FAILURE); 814 } 815 816 /* ... close the descriptor we inherited and go on. */ 817 close(stderr_fd[1]); 818 } else { 819 bool errors = false; 820 char *buf; 821 822 /* In the parent. Print error messages from the child until 823 * it closes the pipe. 824 */ 825 close(stderr_fd[1]); 826 buf = g_malloc(1024); 827 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 828 errors = true; 829 ret = qemu_write_full(STDERR_FILENO, buf, ret); 830 if (ret < 0) { 831 exit(EXIT_FAILURE); 832 } 833 } 834 if (ret < 0) { 835 error_report("Cannot read from daemon: %s", 836 strerror(errno)); 837 exit(EXIT_FAILURE); 838 } 839 840 /* Usually the daemon should not print any message. 841 * Exit with zero status in that case. 842 */ 843 exit(errors); 844 } 845 } 846 847 if (device != NULL && sockpath == NULL) { 848 sockpath = g_malloc(128); 849 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 850 } 851 852 saddr = nbd_build_socket_address(sockpath, bindto, port); 853 854 if (qemu_init_main_loop(&local_err)) { 855 error_report_err(local_err); 856 exit(EXIT_FAILURE); 857 } 858 bdrv_init(); 859 atexit(bdrv_close_all); 860 861 srcpath = argv[optind]; 862 if (imageOpts) { 863 QemuOpts *opts; 864 if (fmt) { 865 error_report("--image-opts and -f are mutually exclusive"); 866 exit(EXIT_FAILURE); 867 } 868 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 869 if (!opts) { 870 qemu_opts_reset(&file_opts); 871 exit(EXIT_FAILURE); 872 } 873 options = qemu_opts_to_qdict(opts, NULL); 874 qemu_opts_reset(&file_opts); 875 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 876 } else { 877 if (fmt) { 878 options = qdict_new(); 879 qdict_put(options, "driver", qstring_from_str(fmt)); 880 } 881 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 882 } 883 884 if (!blk) { 885 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 886 argv[optind]); 887 exit(EXIT_FAILURE); 888 } 889 bs = blk_bs(blk); 890 891 blk_set_enable_write_cache(blk, !writethrough); 892 893 if (sn_opts) { 894 ret = bdrv_snapshot_load_tmp(bs, 895 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 896 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 897 &local_err); 898 } else if (sn_id_or_name) { 899 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 900 &local_err); 901 } 902 if (ret < 0) { 903 error_reportf_err(local_err, "Failed to load snapshot: "); 904 exit(EXIT_FAILURE); 905 } 906 907 bs->detect_zeroes = detect_zeroes; 908 fd_size = blk_getlength(blk); 909 if (fd_size < 0) { 910 error_report("Failed to determine the image length: %s", 911 strerror(-fd_size)); 912 exit(EXIT_FAILURE); 913 } 914 915 if (dev_offset >= fd_size) { 916 error_report("Offset (%lld) has to be smaller than the image size " 917 "(%lld)", 918 (long long int)dev_offset, (long long int)fd_size); 919 exit(EXIT_FAILURE); 920 } 921 fd_size -= dev_offset; 922 923 if (partition != -1) { 924 ret = find_partition(blk, partition, &dev_offset, &fd_size); 925 if (ret < 0) { 926 error_report("Could not find partition %d: %s", partition, 927 strerror(-ret)); 928 exit(EXIT_FAILURE); 929 } 930 } 931 932 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 933 writethrough, NULL, &local_err); 934 if (!exp) { 935 error_report_err(local_err); 936 exit(EXIT_FAILURE); 937 } 938 if (export_name) { 939 nbd_export_set_name(exp, export_name); 940 newproto = true; 941 } 942 943 server_ioc = qio_channel_socket_new(); 944 if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) { 945 object_unref(OBJECT(server_ioc)); 946 error_report_err(local_err); 947 return 1; 948 } 949 950 if (device) { 951 int ret; 952 953 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 954 if (ret != 0) { 955 error_report("Failed to create client thread: %s", strerror(ret)); 956 exit(EXIT_FAILURE); 957 } 958 } else { 959 /* Shut up GCC warnings. */ 960 memset(&client_thread, 0, sizeof(client_thread)); 961 } 962 963 nbd_update_server_watch(); 964 965 /* now when the initialization is (almost) complete, chdir("/") 966 * to free any busy filesystems */ 967 if (chdir("/") < 0) { 968 error_report("Could not chdir to root directory: %s", 969 strerror(errno)); 970 exit(EXIT_FAILURE); 971 } 972 973 if (fork_process) { 974 dup2(old_stderr, STDERR_FILENO); 975 close(old_stderr); 976 } 977 978 state = RUNNING; 979 do { 980 main_loop_wait(false); 981 if (state == TERMINATE) { 982 state = TERMINATING; 983 nbd_export_close(exp); 984 nbd_export_put(exp); 985 exp = NULL; 986 } 987 } while (state != TERMINATED); 988 989 blk_unref(blk); 990 if (sockpath) { 991 unlink(sockpath); 992 } 993 994 qemu_opts_del(sn_opts); 995 996 if (device) { 997 void *ret; 998 pthread_join(client_thread, &ret); 999 exit(ret != NULL); 1000 } else { 1001 exit(EXIT_SUCCESS); 1002 } 1003 } 1004