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 "qemu/systemd.h" 32 #include "block/snapshot.h" 33 #include "qapi/util.h" 34 #include "qapi/qmp/qstring.h" 35 #include "qom/object_interfaces.h" 36 #include "io/channel-socket.h" 37 #include "crypto/init.h" 38 #include "trace/control.h" 39 40 #include <getopt.h> 41 #include <libgen.h> 42 #include <pthread.h> 43 44 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 45 #define QEMU_NBD_OPT_CACHE 256 46 #define QEMU_NBD_OPT_AIO 257 47 #define QEMU_NBD_OPT_DISCARD 258 48 #define QEMU_NBD_OPT_DETECT_ZEROES 259 49 #define QEMU_NBD_OPT_OBJECT 260 50 #define QEMU_NBD_OPT_TLSCREDS 261 51 #define QEMU_NBD_OPT_IMAGE_OPTS 262 52 #define QEMU_NBD_OPT_FORK 263 53 54 #define MBR_SIZE 512 55 56 static NBDExport *exp; 57 static bool newproto; 58 static int verbose; 59 static char *srcpath; 60 static SocketAddress *saddr; 61 static int persistent = 0; 62 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 63 static int shared = 1; 64 static int nb_fds; 65 static QIOChannelSocket *server_ioc; 66 static int server_watch = -1; 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\n" 87 " -D, --description=TEXT with -x, also 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 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 97 " specify tracing options\n" 98 " --fork fork off the server process and exit the parent\n" 99 " once the server is running\n" 100 #ifdef __linux__ 101 "Kernel NBD client support:\n" 102 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 103 " -d, --disconnect disconnect the specified device\n" 104 "\n" 105 #endif 106 "\n" 107 "Block device options:\n" 108 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 109 " -r, --read-only export read-only\n" 110 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 111 " file with backing_file=FILE, redirect the write to\n" 112 " the temporary one\n" 113 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 114 " load an internal snapshot inside FILE and export it\n" 115 " as an read-only device, SNAPSHOT_PARAM format is\n" 116 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 117 " '[ID_OR_NAME]'\n" 118 " -n, --nocache disable host cache\n" 119 " --cache=MODE set cache mode (none, writeback, ...)\n" 120 " --aio=MODE set AIO mode (native or threads)\n" 121 " --discard=MODE set discard mode (ignore, unmap)\n" 122 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 123 " --image-opts treat FILE as a full set of image options\n" 124 "\n" 125 "Report bugs to <qemu-devel@nongnu.org>\n" 126 , name, NBD_DEFAULT_PORT, "DEVICE"); 127 } 128 129 static void version(const char *name) 130 { 131 printf( 132 "%s version 0.0.1\n" 133 "Written by Anthony Liguori.\n" 134 "\n" 135 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n" 136 "This is free software; see the source for copying conditions. There is NO\n" 137 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 138 , name); 139 } 140 141 struct partition_record 142 { 143 uint8_t bootable; 144 uint8_t start_head; 145 uint32_t start_cylinder; 146 uint8_t start_sector; 147 uint8_t system; 148 uint8_t end_head; 149 uint8_t end_cylinder; 150 uint8_t end_sector; 151 uint32_t start_sector_abs; 152 uint32_t nb_sectors_abs; 153 }; 154 155 static void read_partition(uint8_t *p, struct partition_record *r) 156 { 157 r->bootable = p[0]; 158 r->start_head = p[1]; 159 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 160 r->start_sector = p[2] & 0x3f; 161 r->system = p[4]; 162 r->end_head = p[5]; 163 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 164 r->end_sector = p[6] & 0x3f; 165 166 r->start_sector_abs = ldl_le_p(p + 8); 167 r->nb_sectors_abs = ldl_le_p(p + 12); 168 } 169 170 static int find_partition(BlockBackend *blk, int partition, 171 off_t *offset, off_t *size) 172 { 173 struct partition_record mbr[4]; 174 uint8_t data[MBR_SIZE]; 175 int i; 176 int ext_partnum = 4; 177 int ret; 178 179 ret = blk_pread(blk, 0, data, sizeof(data)); 180 if (ret < 0) { 181 error_report("error while reading: %s", strerror(-ret)); 182 exit(EXIT_FAILURE); 183 } 184 185 if (data[510] != 0x55 || data[511] != 0xaa) { 186 return -EINVAL; 187 } 188 189 for (i = 0; i < 4; i++) { 190 read_partition(&data[446 + 16 * i], &mbr[i]); 191 192 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 193 continue; 194 } 195 196 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 197 struct partition_record ext[4]; 198 uint8_t data1[MBR_SIZE]; 199 int j; 200 201 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, 202 data1, sizeof(data1)); 203 if (ret < 0) { 204 error_report("error while reading: %s", strerror(-ret)); 205 exit(EXIT_FAILURE); 206 } 207 208 for (j = 0; j < 4; j++) { 209 read_partition(&data1[446 + 16 * j], &ext[j]); 210 if (!ext[j].system || !ext[j].nb_sectors_abs) { 211 continue; 212 } 213 214 if ((ext_partnum + j + 1) == partition) { 215 *offset = (uint64_t)ext[j].start_sector_abs << 9; 216 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 217 return 0; 218 } 219 } 220 ext_partnum += 4; 221 } else if ((i + 1) == partition) { 222 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 223 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 224 return 0; 225 } 226 } 227 228 return -ENOENT; 229 } 230 231 static void termsig_handler(int signum) 232 { 233 atomic_cmpxchg(&state, RUNNING, TERMINATE); 234 qemu_notify_event(); 235 } 236 237 238 static void *show_parts(void *arg) 239 { 240 char *device = arg; 241 int nbd; 242 243 /* linux just needs an open() to trigger 244 * the partition table update 245 * but remember to load the module with max_part != 0 : 246 * modprobe nbd max_part=63 247 */ 248 nbd = open(device, O_RDWR); 249 if (nbd >= 0) { 250 close(nbd); 251 } 252 return NULL; 253 } 254 255 static void *nbd_client_thread(void *arg) 256 { 257 char *device = arg; 258 off_t size; 259 uint16_t nbdflags; 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, &nbdflags, 275 NULL, NULL, NULL, 276 &size, &local_error); 277 if (ret < 0) { 278 if (local_error) { 279 error_report_err(local_error); 280 } 281 goto out_socket; 282 } 283 284 fd = open(device, O_RDWR); 285 if (fd < 0) { 286 /* Linux-only, we can use %m in printf. */ 287 error_report("Failed to open %s: %m", device); 288 goto out_socket; 289 } 290 291 ret = nbd_init(fd, sioc, nbdflags, size, &local_error); 292 if (ret < 0) { 293 error_report_err(local_error); 294 goto out_fd; 295 } 296 297 /* update partition table */ 298 pthread_create(&show_parts_thread, NULL, show_parts, device); 299 300 if (verbose) { 301 fprintf(stderr, "NBD device %s is now connected to %s\n", 302 device, srcpath); 303 } else { 304 /* Close stderr so that the qemu-nbd process exits. */ 305 dup2(STDOUT_FILENO, STDERR_FILENO); 306 } 307 308 ret = nbd_client(fd); 309 if (ret) { 310 goto out_fd; 311 } 312 close(fd); 313 object_unref(OBJECT(sioc)); 314 kill(getpid(), SIGTERM); 315 return (void *) EXIT_SUCCESS; 316 317 out_fd: 318 close(fd); 319 out_socket: 320 object_unref(OBJECT(sioc)); 321 out: 322 kill(getpid(), SIGTERM); 323 return (void *) EXIT_FAILURE; 324 } 325 326 static int nbd_can_accept(void) 327 { 328 return state == RUNNING && nb_fds < shared; 329 } 330 331 static void nbd_export_closed(NBDExport *exp) 332 { 333 assert(state == TERMINATING); 334 state = TERMINATED; 335 } 336 337 static void nbd_update_server_watch(void); 338 339 static void nbd_client_closed(NBDClient *client) 340 { 341 nb_fds--; 342 if (nb_fds == 0 && !persistent && state == RUNNING) { 343 state = TERMINATE; 344 } 345 nbd_update_server_watch(); 346 nbd_client_put(client); 347 } 348 349 static gboolean nbd_accept(QIOChannel *ioc, GIOCondition cond, gpointer opaque) 350 { 351 QIOChannelSocket *cioc; 352 353 cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc), 354 NULL); 355 if (!cioc) { 356 return TRUE; 357 } 358 359 if (state >= TERMINATE) { 360 object_unref(OBJECT(cioc)); 361 return TRUE; 362 } 363 364 nb_fds++; 365 nbd_update_server_watch(); 366 nbd_client_new(newproto ? NULL : exp, cioc, 367 tlscreds, NULL, nbd_client_closed); 368 object_unref(OBJECT(cioc)); 369 370 return TRUE; 371 } 372 373 static void nbd_update_server_watch(void) 374 { 375 if (nbd_can_accept()) { 376 if (server_watch == -1) { 377 server_watch = qio_channel_add_watch(QIO_CHANNEL(server_ioc), 378 G_IO_IN, 379 nbd_accept, 380 NULL, NULL); 381 } 382 } else { 383 if (server_watch != -1) { 384 g_source_remove(server_watch); 385 server_watch = -1; 386 } 387 } 388 } 389 390 391 static SocketAddress *nbd_build_socket_address(const char *sockpath, 392 const char *bindto, 393 const char *port) 394 { 395 SocketAddress *saddr; 396 397 saddr = g_new0(SocketAddress, 1); 398 if (sockpath) { 399 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 400 saddr->u.q_unix.path = g_strdup(sockpath); 401 } else { 402 InetSocketAddress *inet; 403 saddr->type = SOCKET_ADDRESS_TYPE_INET; 404 inet = &saddr->u.inet; 405 inet->host = g_strdup(bindto); 406 if (port) { 407 inet->port = g_strdup(port); 408 } else { 409 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 410 } 411 } 412 413 return saddr; 414 } 415 416 417 static QemuOptsList file_opts = { 418 .name = "file", 419 .implied_opt_name = "file", 420 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 421 .desc = { 422 /* no elements => accept any params */ 423 { /* end of list */ } 424 }, 425 }; 426 427 static QemuOptsList qemu_object_opts = { 428 .name = "object", 429 .implied_opt_name = "qom-type", 430 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 431 .desc = { 432 { } 433 }, 434 }; 435 436 437 438 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 439 { 440 Object *obj; 441 QCryptoTLSCreds *creds; 442 443 obj = object_resolve_path_component( 444 object_get_objects_root(), id); 445 if (!obj) { 446 error_setg(errp, "No TLS credentials with id '%s'", 447 id); 448 return NULL; 449 } 450 creds = (QCryptoTLSCreds *) 451 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 452 if (!creds) { 453 error_setg(errp, "Object with id '%s' is not TLS credentials", 454 id); 455 return NULL; 456 } 457 458 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 459 error_setg(errp, 460 "Expecting TLS credentials with a server endpoint"); 461 return NULL; 462 } 463 object_ref(obj); 464 return creds; 465 } 466 467 static void setup_address_and_port(const char **address, const char **port) 468 { 469 if (*address == NULL) { 470 *address = "0.0.0.0"; 471 } 472 473 if (*port == NULL) { 474 *port = stringify(NBD_DEFAULT_PORT); 475 } 476 } 477 478 /* 479 * Check socket parameters compatibility when socket activation is used. 480 */ 481 static const char *socket_activation_validate_opts(const char *device, 482 const char *sockpath, 483 const char *address, 484 const char *port) 485 { 486 if (device != NULL) { 487 return "NBD device can't be set when using socket activation"; 488 } 489 490 if (sockpath != NULL) { 491 return "Unix socket can't be set when using socket activation"; 492 } 493 494 if (address != NULL) { 495 return "The interface can't be set when using socket activation"; 496 } 497 498 if (port != NULL) { 499 return "TCP port number can't be set when using socket activation"; 500 } 501 502 return NULL; 503 } 504 505 int main(int argc, char **argv) 506 { 507 BlockBackend *blk; 508 BlockDriverState *bs; 509 off_t dev_offset = 0; 510 uint16_t nbdflags = 0; 511 bool disconnect = false; 512 const char *bindto = NULL; 513 const char *port = NULL; 514 char *sockpath = NULL; 515 char *device = NULL; 516 off_t fd_size; 517 QemuOpts *sn_opts = NULL; 518 const char *sn_id_or_name = NULL; 519 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; 520 struct option lopt[] = { 521 { "help", no_argument, NULL, 'h' }, 522 { "version", no_argument, NULL, 'V' }, 523 { "bind", required_argument, NULL, 'b' }, 524 { "port", required_argument, NULL, 'p' }, 525 { "socket", required_argument, NULL, 'k' }, 526 { "offset", required_argument, NULL, 'o' }, 527 { "read-only", no_argument, NULL, 'r' }, 528 { "partition", required_argument, NULL, 'P' }, 529 { "connect", required_argument, NULL, 'c' }, 530 { "disconnect", no_argument, NULL, 'd' }, 531 { "snapshot", no_argument, NULL, 's' }, 532 { "load-snapshot", required_argument, NULL, 'l' }, 533 { "nocache", no_argument, NULL, 'n' }, 534 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 535 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 536 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 537 { "detect-zeroes", required_argument, NULL, 538 QEMU_NBD_OPT_DETECT_ZEROES }, 539 { "shared", required_argument, NULL, 'e' }, 540 { "format", required_argument, NULL, 'f' }, 541 { "persistent", no_argument, NULL, 't' }, 542 { "verbose", no_argument, NULL, 'v' }, 543 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 544 { "export-name", required_argument, NULL, 'x' }, 545 { "description", required_argument, NULL, 'D' }, 546 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 547 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 548 { "trace", required_argument, NULL, 'T' }, 549 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 550 { NULL, 0, NULL, 0 } 551 }; 552 int ch; 553 int opt_ind = 0; 554 char *end; 555 int flags = BDRV_O_RDWR; 556 int partition = -1; 557 int ret = 0; 558 bool seen_cache = false; 559 bool seen_discard = false; 560 bool seen_aio = false; 561 pthread_t client_thread; 562 const char *fmt = NULL; 563 Error *local_err = NULL; 564 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 565 QDict *options = NULL; 566 const char *export_name = NULL; 567 const char *export_description = NULL; 568 const char *tlscredsid = NULL; 569 bool imageOpts = false; 570 bool writethrough = true; 571 char *trace_file = NULL; 572 bool fork_process = false; 573 int old_stderr = -1; 574 unsigned socket_activation; 575 576 /* The client thread uses SIGTERM to interrupt the server. A signal 577 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 578 */ 579 struct sigaction sa_sigterm; 580 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 581 sa_sigterm.sa_handler = termsig_handler; 582 sigaction(SIGTERM, &sa_sigterm, NULL); 583 584 module_call_init(MODULE_INIT_TRACE); 585 qcrypto_init(&error_fatal); 586 587 module_call_init(MODULE_INIT_QOM); 588 qemu_add_opts(&qemu_object_opts); 589 qemu_add_opts(&qemu_trace_opts); 590 qemu_init_exec_dir(argv[0]); 591 592 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 593 switch (ch) { 594 case 's': 595 flags |= BDRV_O_SNAPSHOT; 596 break; 597 case 'n': 598 optarg = (char *) "none"; 599 /* fallthrough */ 600 case QEMU_NBD_OPT_CACHE: 601 if (seen_cache) { 602 error_report("-n and --cache can only be specified once"); 603 exit(EXIT_FAILURE); 604 } 605 seen_cache = true; 606 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 607 error_report("Invalid cache mode `%s'", optarg); 608 exit(EXIT_FAILURE); 609 } 610 break; 611 case QEMU_NBD_OPT_AIO: 612 if (seen_aio) { 613 error_report("--aio can only be specified once"); 614 exit(EXIT_FAILURE); 615 } 616 seen_aio = true; 617 if (!strcmp(optarg, "native")) { 618 flags |= BDRV_O_NATIVE_AIO; 619 } else if (!strcmp(optarg, "threads")) { 620 /* this is the default */ 621 } else { 622 error_report("invalid aio mode `%s'", optarg); 623 exit(EXIT_FAILURE); 624 } 625 break; 626 case QEMU_NBD_OPT_DISCARD: 627 if (seen_discard) { 628 error_report("--discard can only be specified once"); 629 exit(EXIT_FAILURE); 630 } 631 seen_discard = true; 632 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 633 error_report("Invalid discard mode `%s'", optarg); 634 exit(EXIT_FAILURE); 635 } 636 break; 637 case QEMU_NBD_OPT_DETECT_ZEROES: 638 detect_zeroes = 639 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 640 optarg, 641 BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX, 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 'k': 702 sockpath = optarg; 703 if (sockpath[0] != '/') { 704 error_report("socket path must be absolute"); 705 exit(EXIT_FAILURE); 706 } 707 break; 708 case 'd': 709 disconnect = true; 710 break; 711 case 'c': 712 device = optarg; 713 break; 714 case 'e': 715 shared = strtol(optarg, &end, 0); 716 if (*end) { 717 error_report("Invalid shared device number '%s'", optarg); 718 exit(EXIT_FAILURE); 719 } 720 if (shared < 1) { 721 error_report("Shared device number must be greater than 0"); 722 exit(EXIT_FAILURE); 723 } 724 break; 725 case 'f': 726 fmt = optarg; 727 break; 728 case 't': 729 persistent = 1; 730 break; 731 case 'x': 732 export_name = optarg; 733 break; 734 case 'D': 735 export_description = optarg; 736 break; 737 case 'v': 738 verbose = 1; 739 break; 740 case 'V': 741 version(argv[0]); 742 exit(0); 743 break; 744 case 'h': 745 usage(argv[0]); 746 exit(0); 747 break; 748 case '?': 749 error_report("Try `%s --help' for more information.", argv[0]); 750 exit(EXIT_FAILURE); 751 case QEMU_NBD_OPT_OBJECT: { 752 QemuOpts *opts; 753 opts = qemu_opts_parse_noisily(&qemu_object_opts, 754 optarg, true); 755 if (!opts) { 756 exit(EXIT_FAILURE); 757 } 758 } break; 759 case QEMU_NBD_OPT_TLSCREDS: 760 tlscredsid = optarg; 761 break; 762 case QEMU_NBD_OPT_IMAGE_OPTS: 763 imageOpts = true; 764 break; 765 case 'T': 766 g_free(trace_file); 767 trace_file = trace_opt_parse(optarg); 768 break; 769 case QEMU_NBD_OPT_FORK: 770 fork_process = true; 771 break; 772 } 773 } 774 775 if ((argc - optind) != 1) { 776 error_report("Invalid number of arguments"); 777 error_printf("Try `%s --help' for more information.\n", argv[0]); 778 exit(EXIT_FAILURE); 779 } 780 781 if (qemu_opts_foreach(&qemu_object_opts, 782 user_creatable_add_opts_foreach, 783 NULL, NULL)) { 784 exit(EXIT_FAILURE); 785 } 786 787 if (!trace_init_backends()) { 788 exit(1); 789 } 790 trace_init_file(trace_file); 791 qemu_set_log(LOG_TRACE); 792 793 socket_activation = check_socket_activation(); 794 if (socket_activation == 0) { 795 setup_address_and_port(&bindto, &port); 796 } else { 797 /* Using socket activation - check user didn't use -p etc. */ 798 const char *err_msg = socket_activation_validate_opts(device, sockpath, 799 bindto, port); 800 if (err_msg != NULL) { 801 error_report("%s", err_msg); 802 exit(EXIT_FAILURE); 803 } 804 805 /* qemu-nbd can only listen on a single socket. */ 806 if (socket_activation > 1) { 807 error_report("qemu-nbd does not support socket activation with %s > 1", 808 "LISTEN_FDS"); 809 exit(EXIT_FAILURE); 810 } 811 } 812 813 if (tlscredsid) { 814 if (sockpath) { 815 error_report("TLS is only supported with IPv4/IPv6"); 816 exit(EXIT_FAILURE); 817 } 818 if (device) { 819 error_report("TLS is not supported with a host device"); 820 exit(EXIT_FAILURE); 821 } 822 if (!export_name) { 823 /* Set the default NBD protocol export name, since 824 * we *must* use new style protocol for TLS */ 825 export_name = ""; 826 } 827 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 828 if (local_err) { 829 error_report("Failed to get TLS creds %s", 830 error_get_pretty(local_err)); 831 exit(EXIT_FAILURE); 832 } 833 } 834 835 if (disconnect) { 836 int nbdfd = open(argv[optind], O_RDWR); 837 if (nbdfd < 0) { 838 error_report("Cannot open %s: %s", argv[optind], 839 strerror(errno)); 840 exit(EXIT_FAILURE); 841 } 842 nbd_disconnect(nbdfd); 843 844 close(nbdfd); 845 846 printf("%s disconnected\n", argv[optind]); 847 848 return 0; 849 } 850 851 if ((device && !verbose) || fork_process) { 852 int stderr_fd[2]; 853 pid_t pid; 854 int ret; 855 856 if (qemu_pipe(stderr_fd) < 0) { 857 error_report("Error setting up communication pipe: %s", 858 strerror(errno)); 859 exit(EXIT_FAILURE); 860 } 861 862 /* Now daemonize, but keep a communication channel open to 863 * print errors and exit with the proper status code. 864 */ 865 pid = fork(); 866 if (pid < 0) { 867 error_report("Failed to fork: %s", strerror(errno)); 868 exit(EXIT_FAILURE); 869 } else if (pid == 0) { 870 close(stderr_fd[0]); 871 ret = qemu_daemon(1, 0); 872 873 /* Temporarily redirect stderr to the parent's pipe... */ 874 old_stderr = dup(STDERR_FILENO); 875 dup2(stderr_fd[1], STDERR_FILENO); 876 if (ret < 0) { 877 error_report("Failed to daemonize: %s", strerror(errno)); 878 exit(EXIT_FAILURE); 879 } 880 881 /* ... close the descriptor we inherited and go on. */ 882 close(stderr_fd[1]); 883 } else { 884 bool errors = false; 885 char *buf; 886 887 /* In the parent. Print error messages from the child until 888 * it closes the pipe. 889 */ 890 close(stderr_fd[1]); 891 buf = g_malloc(1024); 892 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 893 errors = true; 894 ret = qemu_write_full(STDERR_FILENO, buf, ret); 895 if (ret < 0) { 896 exit(EXIT_FAILURE); 897 } 898 } 899 if (ret < 0) { 900 error_report("Cannot read from daemon: %s", 901 strerror(errno)); 902 exit(EXIT_FAILURE); 903 } 904 905 /* Usually the daemon should not print any message. 906 * Exit with zero status in that case. 907 */ 908 exit(errors); 909 } 910 } 911 912 if (device != NULL && sockpath == NULL) { 913 sockpath = g_malloc(128); 914 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 915 } 916 917 if (socket_activation == 0) { 918 server_ioc = qio_channel_socket_new(); 919 saddr = nbd_build_socket_address(sockpath, bindto, port); 920 if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) { 921 object_unref(OBJECT(server_ioc)); 922 error_report_err(local_err); 923 return 1; 924 } 925 } else { 926 /* See comment in check_socket_activation above. */ 927 assert(socket_activation == 1); 928 server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD, 929 &local_err); 930 if (server_ioc == NULL) { 931 error_report("Failed to use socket activation: %s", 932 error_get_pretty(local_err)); 933 exit(EXIT_FAILURE); 934 } 935 } 936 937 if (qemu_init_main_loop(&local_err)) { 938 error_report_err(local_err); 939 exit(EXIT_FAILURE); 940 } 941 bdrv_init(); 942 atexit(bdrv_close_all); 943 944 srcpath = argv[optind]; 945 if (imageOpts) { 946 QemuOpts *opts; 947 if (fmt) { 948 error_report("--image-opts and -f are mutually exclusive"); 949 exit(EXIT_FAILURE); 950 } 951 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 952 if (!opts) { 953 qemu_opts_reset(&file_opts); 954 exit(EXIT_FAILURE); 955 } 956 options = qemu_opts_to_qdict(opts, NULL); 957 qemu_opts_reset(&file_opts); 958 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 959 } else { 960 if (fmt) { 961 options = qdict_new(); 962 qdict_put_str(options, "driver", fmt); 963 } 964 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 965 } 966 967 if (!blk) { 968 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 969 argv[optind]); 970 exit(EXIT_FAILURE); 971 } 972 bs = blk_bs(blk); 973 974 blk_set_enable_write_cache(blk, !writethrough); 975 976 if (sn_opts) { 977 ret = bdrv_snapshot_load_tmp(bs, 978 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 979 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 980 &local_err); 981 } else if (sn_id_or_name) { 982 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 983 &local_err); 984 } 985 if (ret < 0) { 986 error_reportf_err(local_err, "Failed to load snapshot: "); 987 exit(EXIT_FAILURE); 988 } 989 990 bs->detect_zeroes = detect_zeroes; 991 fd_size = blk_getlength(blk); 992 if (fd_size < 0) { 993 error_report("Failed to determine the image length: %s", 994 strerror(-fd_size)); 995 exit(EXIT_FAILURE); 996 } 997 998 if (dev_offset >= fd_size) { 999 error_report("Offset (%lld) has to be smaller than the image size " 1000 "(%lld)", 1001 (long long int)dev_offset, (long long int)fd_size); 1002 exit(EXIT_FAILURE); 1003 } 1004 fd_size -= dev_offset; 1005 1006 if (partition != -1) { 1007 ret = find_partition(blk, partition, &dev_offset, &fd_size); 1008 if (ret < 0) { 1009 error_report("Could not find partition %d: %s", partition, 1010 strerror(-ret)); 1011 exit(EXIT_FAILURE); 1012 } 1013 } 1014 1015 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1016 writethrough, NULL, &local_err); 1017 if (!exp) { 1018 error_report_err(local_err); 1019 exit(EXIT_FAILURE); 1020 } 1021 if (export_name) { 1022 nbd_export_set_name(exp, export_name); 1023 nbd_export_set_description(exp, export_description); 1024 newproto = true; 1025 } else if (export_description) { 1026 error_report("Export description requires an export name"); 1027 exit(EXIT_FAILURE); 1028 } 1029 1030 if (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 } else { 1039 /* Shut up GCC warnings. */ 1040 memset(&client_thread, 0, sizeof(client_thread)); 1041 } 1042 1043 nbd_update_server_watch(); 1044 1045 /* now when the initialization is (almost) complete, chdir("/") 1046 * to free any busy filesystems */ 1047 if (chdir("/") < 0) { 1048 error_report("Could not chdir to root directory: %s", 1049 strerror(errno)); 1050 exit(EXIT_FAILURE); 1051 } 1052 1053 if (fork_process) { 1054 dup2(old_stderr, STDERR_FILENO); 1055 close(old_stderr); 1056 } 1057 1058 state = RUNNING; 1059 do { 1060 main_loop_wait(false); 1061 if (state == TERMINATE) { 1062 state = TERMINATING; 1063 nbd_export_close(exp); 1064 nbd_export_put(exp); 1065 exp = NULL; 1066 } 1067 } while (state != TERMINATED); 1068 1069 blk_unref(blk); 1070 if (sockpath) { 1071 unlink(sockpath); 1072 } 1073 1074 qemu_opts_del(sn_opts); 1075 1076 if (device) { 1077 void *ret; 1078 pthread_join(client_thread, &ret); 1079 exit(ret != NULL); 1080 } else { 1081 exit(EXIT_SUCCESS); 1082 } 1083 } 1084