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-common.h" 26 #include "qemu/cutils.h" 27 #include "sysemu/block-backend.h" 28 #include "block/block_int.h" 29 #include "block/nbd.h" 30 #include "qemu/main-loop.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/util.h" 38 #include "qapi/qmp/qstring.h" 39 #include "qom/object_interfaces.h" 40 #include "io/channel-socket.h" 41 #include "crypto/init.h" 42 #include "trace/control.h" 43 #include "qemu-version.h" 44 45 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 46 #define QEMU_NBD_OPT_CACHE 256 47 #define QEMU_NBD_OPT_AIO 257 48 #define QEMU_NBD_OPT_DISCARD 258 49 #define QEMU_NBD_OPT_DETECT_ZEROES 259 50 #define QEMU_NBD_OPT_OBJECT 260 51 #define QEMU_NBD_OPT_TLSCREDS 261 52 #define QEMU_NBD_OPT_IMAGE_OPTS 262 53 #define QEMU_NBD_OPT_FORK 263 54 55 #define MBR_SIZE 512 56 57 static NBDExport *exp; 58 static bool newproto; 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 QIOChannelSocket *server_ioc; 67 static int server_watch = -1; 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_VERSION QEMU_PKGVERSION "\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 gboolean nbd_accept(QIOChannel *ioc, GIOCondition cond, gpointer opaque) 349 { 350 QIOChannelSocket *cioc; 351 352 cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc), 353 NULL); 354 if (!cioc) { 355 return TRUE; 356 } 357 358 if (state >= TERMINATE) { 359 object_unref(OBJECT(cioc)); 360 return TRUE; 361 } 362 363 nb_fds++; 364 nbd_update_server_watch(); 365 nbd_client_new(newproto ? NULL : exp, cioc, 366 tlscreds, NULL, nbd_client_closed); 367 object_unref(OBJECT(cioc)); 368 369 return TRUE; 370 } 371 372 static void nbd_update_server_watch(void) 373 { 374 if (nbd_can_accept()) { 375 if (server_watch == -1) { 376 server_watch = qio_channel_add_watch(QIO_CHANNEL(server_ioc), 377 G_IO_IN, 378 nbd_accept, 379 NULL, NULL); 380 } 381 } else { 382 if (server_watch != -1) { 383 g_source_remove(server_watch); 384 server_watch = -1; 385 } 386 } 387 } 388 389 390 static SocketAddress *nbd_build_socket_address(const char *sockpath, 391 const char *bindto, 392 const char *port) 393 { 394 SocketAddress *saddr; 395 396 saddr = g_new0(SocketAddress, 1); 397 if (sockpath) { 398 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 399 saddr->u.q_unix.path = g_strdup(sockpath); 400 } else { 401 InetSocketAddress *inet; 402 saddr->type = SOCKET_ADDRESS_TYPE_INET; 403 inet = &saddr->u.inet; 404 inet->host = g_strdup(bindto); 405 if (port) { 406 inet->port = g_strdup(port); 407 } else { 408 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 409 } 410 } 411 412 return saddr; 413 } 414 415 416 static QemuOptsList file_opts = { 417 .name = "file", 418 .implied_opt_name = "file", 419 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 420 .desc = { 421 /* no elements => accept any params */ 422 { /* end of list */ } 423 }, 424 }; 425 426 static QemuOptsList qemu_object_opts = { 427 .name = "object", 428 .implied_opt_name = "qom-type", 429 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 430 .desc = { 431 { } 432 }, 433 }; 434 435 436 437 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 438 { 439 Object *obj; 440 QCryptoTLSCreds *creds; 441 442 obj = object_resolve_path_component( 443 object_get_objects_root(), id); 444 if (!obj) { 445 error_setg(errp, "No TLS credentials with id '%s'", 446 id); 447 return NULL; 448 } 449 creds = (QCryptoTLSCreds *) 450 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 451 if (!creds) { 452 error_setg(errp, "Object with id '%s' is not TLS credentials", 453 id); 454 return NULL; 455 } 456 457 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 458 error_setg(errp, 459 "Expecting TLS credentials with a server endpoint"); 460 return NULL; 461 } 462 object_ref(obj); 463 return creds; 464 } 465 466 static void setup_address_and_port(const char **address, const char **port) 467 { 468 if (*address == NULL) { 469 *address = "0.0.0.0"; 470 } 471 472 if (*port == NULL) { 473 *port = stringify(NBD_DEFAULT_PORT); 474 } 475 } 476 477 /* 478 * Check socket parameters compatibility when socket activation is used. 479 */ 480 static const char *socket_activation_validate_opts(const char *device, 481 const char *sockpath, 482 const char *address, 483 const char *port) 484 { 485 if (device != NULL) { 486 return "NBD device can't be set when using socket activation"; 487 } 488 489 if (sockpath != NULL) { 490 return "Unix socket can't be set when using socket activation"; 491 } 492 493 if (address != NULL) { 494 return "The interface can't be set when using socket activation"; 495 } 496 497 if (port != NULL) { 498 return "TCP port number can't be set when using socket activation"; 499 } 500 501 return NULL; 502 } 503 504 int main(int argc, char **argv) 505 { 506 BlockBackend *blk; 507 BlockDriverState *bs; 508 off_t dev_offset = 0; 509 uint16_t nbdflags = 0; 510 bool disconnect = false; 511 const char *bindto = NULL; 512 const char *port = NULL; 513 char *sockpath = NULL; 514 char *device = NULL; 515 off_t fd_size; 516 QemuOpts *sn_opts = NULL; 517 const char *sn_id_or_name = NULL; 518 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; 519 struct option lopt[] = { 520 { "help", no_argument, NULL, 'h' }, 521 { "version", no_argument, NULL, 'V' }, 522 { "bind", required_argument, NULL, 'b' }, 523 { "port", required_argument, NULL, 'p' }, 524 { "socket", required_argument, NULL, 'k' }, 525 { "offset", required_argument, NULL, 'o' }, 526 { "read-only", no_argument, NULL, 'r' }, 527 { "partition", required_argument, NULL, 'P' }, 528 { "connect", required_argument, NULL, 'c' }, 529 { "disconnect", no_argument, NULL, 'd' }, 530 { "snapshot", no_argument, NULL, 's' }, 531 { "load-snapshot", required_argument, NULL, 'l' }, 532 { "nocache", no_argument, NULL, 'n' }, 533 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 534 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 535 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 536 { "detect-zeroes", required_argument, NULL, 537 QEMU_NBD_OPT_DETECT_ZEROES }, 538 { "shared", required_argument, NULL, 'e' }, 539 { "format", required_argument, NULL, 'f' }, 540 { "persistent", no_argument, NULL, 't' }, 541 { "verbose", no_argument, NULL, 'v' }, 542 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 543 { "export-name", required_argument, NULL, 'x' }, 544 { "description", required_argument, NULL, 'D' }, 545 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 546 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 547 { "trace", required_argument, NULL, 'T' }, 548 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 549 { NULL, 0, NULL, 0 } 550 }; 551 int ch; 552 int opt_ind = 0; 553 char *end; 554 int flags = BDRV_O_RDWR; 555 int partition = -1; 556 int ret = 0; 557 bool seen_cache = false; 558 bool seen_discard = false; 559 bool seen_aio = false; 560 pthread_t client_thread; 561 const char *fmt = NULL; 562 Error *local_err = NULL; 563 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 564 QDict *options = NULL; 565 const char *export_name = NULL; 566 const char *export_description = NULL; 567 const char *tlscredsid = NULL; 568 bool imageOpts = false; 569 bool writethrough = true; 570 char *trace_file = NULL; 571 bool fork_process = false; 572 int old_stderr = -1; 573 unsigned socket_activation; 574 575 /* The client thread uses SIGTERM to interrupt the server. A signal 576 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 577 */ 578 struct sigaction sa_sigterm; 579 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 580 sa_sigterm.sa_handler = termsig_handler; 581 sigaction(SIGTERM, &sa_sigterm, NULL); 582 583 #ifdef CONFIG_POSIX 584 signal(SIGPIPE, SIG_IGN); 585 #endif 586 587 module_call_init(MODULE_INIT_TRACE); 588 qcrypto_init(&error_fatal); 589 590 module_call_init(MODULE_INIT_QOM); 591 qemu_add_opts(&qemu_object_opts); 592 qemu_add_opts(&qemu_trace_opts); 593 qemu_init_exec_dir(argv[0]); 594 595 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 596 switch (ch) { 597 case 's': 598 flags |= BDRV_O_SNAPSHOT; 599 break; 600 case 'n': 601 optarg = (char *) "none"; 602 /* fallthrough */ 603 case QEMU_NBD_OPT_CACHE: 604 if (seen_cache) { 605 error_report("-n and --cache can only be specified once"); 606 exit(EXIT_FAILURE); 607 } 608 seen_cache = true; 609 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 610 error_report("Invalid cache mode `%s'", optarg); 611 exit(EXIT_FAILURE); 612 } 613 break; 614 case QEMU_NBD_OPT_AIO: 615 if (seen_aio) { 616 error_report("--aio can only be specified once"); 617 exit(EXIT_FAILURE); 618 } 619 seen_aio = true; 620 if (!strcmp(optarg, "native")) { 621 flags |= BDRV_O_NATIVE_AIO; 622 } else if (!strcmp(optarg, "threads")) { 623 /* this is the default */ 624 } else { 625 error_report("invalid aio mode `%s'", optarg); 626 exit(EXIT_FAILURE); 627 } 628 break; 629 case QEMU_NBD_OPT_DISCARD: 630 if (seen_discard) { 631 error_report("--discard can only be specified once"); 632 exit(EXIT_FAILURE); 633 } 634 seen_discard = true; 635 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 636 error_report("Invalid discard mode `%s'", optarg); 637 exit(EXIT_FAILURE); 638 } 639 break; 640 case QEMU_NBD_OPT_DETECT_ZEROES: 641 detect_zeroes = 642 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 643 optarg, 644 BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX, 645 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 646 &local_err); 647 if (local_err) { 648 error_reportf_err(local_err, 649 "Failed to parse detect_zeroes mode: "); 650 exit(EXIT_FAILURE); 651 } 652 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 653 !(flags & BDRV_O_UNMAP)) { 654 error_report("setting detect-zeroes to unmap is not allowed " 655 "without setting discard operation to unmap"); 656 exit(EXIT_FAILURE); 657 } 658 break; 659 case 'b': 660 bindto = optarg; 661 break; 662 case 'p': 663 port = optarg; 664 break; 665 case 'o': 666 dev_offset = strtoll (optarg, &end, 0); 667 if (*end) { 668 error_report("Invalid offset `%s'", optarg); 669 exit(EXIT_FAILURE); 670 } 671 if (dev_offset < 0) { 672 error_report("Offset must be positive `%s'", optarg); 673 exit(EXIT_FAILURE); 674 } 675 break; 676 case 'l': 677 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 678 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 679 optarg, false); 680 if (!sn_opts) { 681 error_report("Failed in parsing snapshot param `%s'", 682 optarg); 683 exit(EXIT_FAILURE); 684 } 685 } else { 686 sn_id_or_name = optarg; 687 } 688 /* fall through */ 689 case 'r': 690 nbdflags |= NBD_FLAG_READ_ONLY; 691 flags &= ~BDRV_O_RDWR; 692 break; 693 case 'P': 694 partition = strtol(optarg, &end, 0); 695 if (*end) { 696 error_report("Invalid partition `%s'", optarg); 697 exit(EXIT_FAILURE); 698 } 699 if (partition < 1 || partition > 8) { 700 error_report("Invalid partition %d", partition); 701 exit(EXIT_FAILURE); 702 } 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 if (qemu_opts_foreach(&qemu_object_opts, 785 user_creatable_add_opts_foreach, 786 NULL, NULL)) { 787 exit(EXIT_FAILURE); 788 } 789 790 if (!trace_init_backends()) { 791 exit(1); 792 } 793 trace_init_file(trace_file); 794 qemu_set_log(LOG_TRACE); 795 796 socket_activation = check_socket_activation(); 797 if (socket_activation == 0) { 798 setup_address_and_port(&bindto, &port); 799 } else { 800 /* Using socket activation - check user didn't use -p etc. */ 801 const char *err_msg = socket_activation_validate_opts(device, sockpath, 802 bindto, port); 803 if (err_msg != NULL) { 804 error_report("%s", err_msg); 805 exit(EXIT_FAILURE); 806 } 807 808 /* qemu-nbd can only listen on a single socket. */ 809 if (socket_activation > 1) { 810 error_report("qemu-nbd does not support socket activation with %s > 1", 811 "LISTEN_FDS"); 812 exit(EXIT_FAILURE); 813 } 814 } 815 816 if (tlscredsid) { 817 if (sockpath) { 818 error_report("TLS is only supported with IPv4/IPv6"); 819 exit(EXIT_FAILURE); 820 } 821 if (device) { 822 error_report("TLS is not supported with a host device"); 823 exit(EXIT_FAILURE); 824 } 825 if (!export_name) { 826 /* Set the default NBD protocol export name, since 827 * we *must* use new style protocol for TLS */ 828 export_name = ""; 829 } 830 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 831 if (local_err) { 832 error_report("Failed to get TLS creds %s", 833 error_get_pretty(local_err)); 834 exit(EXIT_FAILURE); 835 } 836 } 837 838 if (disconnect) { 839 int nbdfd = open(argv[optind], O_RDWR); 840 if (nbdfd < 0) { 841 error_report("Cannot open %s: %s", argv[optind], 842 strerror(errno)); 843 exit(EXIT_FAILURE); 844 } 845 nbd_disconnect(nbdfd); 846 847 close(nbdfd); 848 849 printf("%s disconnected\n", argv[optind]); 850 851 return 0; 852 } 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 if (socket_activation == 0) { 921 server_ioc = qio_channel_socket_new(); 922 saddr = nbd_build_socket_address(sockpath, bindto, port); 923 if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) { 924 object_unref(OBJECT(server_ioc)); 925 error_report_err(local_err); 926 return 1; 927 } 928 } else { 929 /* See comment in check_socket_activation above. */ 930 assert(socket_activation == 1); 931 server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD, 932 &local_err); 933 if (server_ioc == NULL) { 934 error_report("Failed to use socket activation: %s", 935 error_get_pretty(local_err)); 936 exit(EXIT_FAILURE); 937 } 938 } 939 940 if (qemu_init_main_loop(&local_err)) { 941 error_report_err(local_err); 942 exit(EXIT_FAILURE); 943 } 944 bdrv_init(); 945 atexit(bdrv_close_all); 946 947 srcpath = argv[optind]; 948 if (imageOpts) { 949 QemuOpts *opts; 950 if (fmt) { 951 error_report("--image-opts and -f are mutually exclusive"); 952 exit(EXIT_FAILURE); 953 } 954 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 955 if (!opts) { 956 qemu_opts_reset(&file_opts); 957 exit(EXIT_FAILURE); 958 } 959 options = qemu_opts_to_qdict(opts, NULL); 960 qemu_opts_reset(&file_opts); 961 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 962 } else { 963 if (fmt) { 964 options = qdict_new(); 965 qdict_put_str(options, "driver", fmt); 966 } 967 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 968 } 969 970 if (!blk) { 971 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 972 argv[optind]); 973 exit(EXIT_FAILURE); 974 } 975 bs = blk_bs(blk); 976 977 blk_set_enable_write_cache(blk, !writethrough); 978 979 if (sn_opts) { 980 ret = bdrv_snapshot_load_tmp(bs, 981 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 982 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 983 &local_err); 984 } else if (sn_id_or_name) { 985 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 986 &local_err); 987 } 988 if (ret < 0) { 989 error_reportf_err(local_err, "Failed to load snapshot: "); 990 exit(EXIT_FAILURE); 991 } 992 993 bs->detect_zeroes = detect_zeroes; 994 fd_size = blk_getlength(blk); 995 if (fd_size < 0) { 996 error_report("Failed to determine the image length: %s", 997 strerror(-fd_size)); 998 exit(EXIT_FAILURE); 999 } 1000 1001 if (dev_offset >= fd_size) { 1002 error_report("Offset (%lld) has to be smaller than the image size " 1003 "(%lld)", 1004 (long long int)dev_offset, (long long int)fd_size); 1005 exit(EXIT_FAILURE); 1006 } 1007 fd_size -= dev_offset; 1008 1009 if (partition != -1) { 1010 ret = find_partition(blk, partition, &dev_offset, &fd_size); 1011 if (ret < 0) { 1012 error_report("Could not find partition %d: %s", partition, 1013 strerror(-ret)); 1014 exit(EXIT_FAILURE); 1015 } 1016 } 1017 1018 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1019 writethrough, NULL, &local_err); 1020 if (!exp) { 1021 error_report_err(local_err); 1022 exit(EXIT_FAILURE); 1023 } 1024 if (export_name) { 1025 nbd_export_set_name(exp, export_name); 1026 nbd_export_set_description(exp, export_description); 1027 newproto = true; 1028 } else if (export_description) { 1029 error_report("Export description requires an export name"); 1030 exit(EXIT_FAILURE); 1031 } 1032 1033 if (device) { 1034 int ret; 1035 1036 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1037 if (ret != 0) { 1038 error_report("Failed to create client thread: %s", strerror(ret)); 1039 exit(EXIT_FAILURE); 1040 } 1041 } else { 1042 /* Shut up GCC warnings. */ 1043 memset(&client_thread, 0, sizeof(client_thread)); 1044 } 1045 1046 nbd_update_server_watch(); 1047 1048 /* now when the initialization is (almost) complete, chdir("/") 1049 * to free any busy filesystems */ 1050 if (chdir("/") < 0) { 1051 error_report("Could not chdir to root directory: %s", 1052 strerror(errno)); 1053 exit(EXIT_FAILURE); 1054 } 1055 1056 if (fork_process) { 1057 dup2(old_stderr, STDERR_FILENO); 1058 close(old_stderr); 1059 } 1060 1061 state = RUNNING; 1062 do { 1063 main_loop_wait(false); 1064 if (state == TERMINATE) { 1065 state = TERMINATING; 1066 nbd_export_close(exp); 1067 nbd_export_put(exp); 1068 exp = NULL; 1069 } 1070 } while (state != TERMINATED); 1071 1072 blk_unref(blk); 1073 if (sockpath) { 1074 unlink(sockpath); 1075 } 1076 1077 qemu_opts_del(sn_opts); 1078 1079 if (device) { 1080 void *ret; 1081 pthread_join(client_thread, &ret); 1082 exit(ret != NULL); 1083 } else { 1084 exit(EXIT_SUCCESS); 1085 } 1086 } 1087