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); 292 if (ret < 0) { 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 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) 339 { 340 nb_fds--; 341 if (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 module_call_init(MODULE_INIT_TRACE); 584 qcrypto_init(&error_fatal); 585 586 module_call_init(MODULE_INIT_QOM); 587 qemu_add_opts(&qemu_object_opts); 588 qemu_add_opts(&qemu_trace_opts); 589 qemu_init_exec_dir(argv[0]); 590 591 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 592 switch (ch) { 593 case 's': 594 flags |= BDRV_O_SNAPSHOT; 595 break; 596 case 'n': 597 optarg = (char *) "none"; 598 /* fallthrough */ 599 case QEMU_NBD_OPT_CACHE: 600 if (seen_cache) { 601 error_report("-n and --cache can only be specified once"); 602 exit(EXIT_FAILURE); 603 } 604 seen_cache = true; 605 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 606 error_report("Invalid cache mode `%s'", optarg); 607 exit(EXIT_FAILURE); 608 } 609 break; 610 case QEMU_NBD_OPT_AIO: 611 if (seen_aio) { 612 error_report("--aio can only be specified once"); 613 exit(EXIT_FAILURE); 614 } 615 seen_aio = true; 616 if (!strcmp(optarg, "native")) { 617 flags |= BDRV_O_NATIVE_AIO; 618 } else if (!strcmp(optarg, "threads")) { 619 /* this is the default */ 620 } else { 621 error_report("invalid aio mode `%s'", optarg); 622 exit(EXIT_FAILURE); 623 } 624 break; 625 case QEMU_NBD_OPT_DISCARD: 626 if (seen_discard) { 627 error_report("--discard can only be specified once"); 628 exit(EXIT_FAILURE); 629 } 630 seen_discard = true; 631 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 632 error_report("Invalid discard mode `%s'", optarg); 633 exit(EXIT_FAILURE); 634 } 635 break; 636 case QEMU_NBD_OPT_DETECT_ZEROES: 637 detect_zeroes = 638 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 639 optarg, 640 BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX, 641 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 642 &local_err); 643 if (local_err) { 644 error_reportf_err(local_err, 645 "Failed to parse detect_zeroes mode: "); 646 exit(EXIT_FAILURE); 647 } 648 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 649 !(flags & BDRV_O_UNMAP)) { 650 error_report("setting detect-zeroes to unmap is not allowed " 651 "without setting discard operation to unmap"); 652 exit(EXIT_FAILURE); 653 } 654 break; 655 case 'b': 656 bindto = optarg; 657 break; 658 case 'p': 659 port = optarg; 660 break; 661 case 'o': 662 dev_offset = strtoll (optarg, &end, 0); 663 if (*end) { 664 error_report("Invalid offset `%s'", optarg); 665 exit(EXIT_FAILURE); 666 } 667 if (dev_offset < 0) { 668 error_report("Offset must be positive `%s'", optarg); 669 exit(EXIT_FAILURE); 670 } 671 break; 672 case 'l': 673 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 674 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 675 optarg, false); 676 if (!sn_opts) { 677 error_report("Failed in parsing snapshot param `%s'", 678 optarg); 679 exit(EXIT_FAILURE); 680 } 681 } else { 682 sn_id_or_name = optarg; 683 } 684 /* fall through */ 685 case 'r': 686 nbdflags |= NBD_FLAG_READ_ONLY; 687 flags &= ~BDRV_O_RDWR; 688 break; 689 case 'P': 690 partition = strtol(optarg, &end, 0); 691 if (*end) { 692 error_report("Invalid partition `%s'", optarg); 693 exit(EXIT_FAILURE); 694 } 695 if (partition < 1 || partition > 8) { 696 error_report("Invalid partition %d", partition); 697 exit(EXIT_FAILURE); 698 } 699 break; 700 case 'k': 701 sockpath = optarg; 702 if (sockpath[0] != '/') { 703 error_report("socket path must be absolute"); 704 exit(EXIT_FAILURE); 705 } 706 break; 707 case 'd': 708 disconnect = true; 709 break; 710 case 'c': 711 device = optarg; 712 break; 713 case 'e': 714 shared = strtol(optarg, &end, 0); 715 if (*end) { 716 error_report("Invalid shared device number '%s'", optarg); 717 exit(EXIT_FAILURE); 718 } 719 if (shared < 1) { 720 error_report("Shared device number must be greater than 0"); 721 exit(EXIT_FAILURE); 722 } 723 break; 724 case 'f': 725 fmt = optarg; 726 break; 727 case 't': 728 persistent = 1; 729 break; 730 case 'x': 731 export_name = optarg; 732 break; 733 case 'D': 734 export_description = optarg; 735 break; 736 case 'v': 737 verbose = 1; 738 break; 739 case 'V': 740 version(argv[0]); 741 exit(0); 742 break; 743 case 'h': 744 usage(argv[0]); 745 exit(0); 746 break; 747 case '?': 748 error_report("Try `%s --help' for more information.", argv[0]); 749 exit(EXIT_FAILURE); 750 case QEMU_NBD_OPT_OBJECT: { 751 QemuOpts *opts; 752 opts = qemu_opts_parse_noisily(&qemu_object_opts, 753 optarg, true); 754 if (!opts) { 755 exit(EXIT_FAILURE); 756 } 757 } break; 758 case QEMU_NBD_OPT_TLSCREDS: 759 tlscredsid = optarg; 760 break; 761 case QEMU_NBD_OPT_IMAGE_OPTS: 762 imageOpts = true; 763 break; 764 case 'T': 765 g_free(trace_file); 766 trace_file = trace_opt_parse(optarg); 767 break; 768 case QEMU_NBD_OPT_FORK: 769 fork_process = true; 770 break; 771 } 772 } 773 774 if ((argc - optind) != 1) { 775 error_report("Invalid number of arguments"); 776 error_printf("Try `%s --help' for more information.\n", argv[0]); 777 exit(EXIT_FAILURE); 778 } 779 780 if (qemu_opts_foreach(&qemu_object_opts, 781 user_creatable_add_opts_foreach, 782 NULL, NULL)) { 783 exit(EXIT_FAILURE); 784 } 785 786 if (!trace_init_backends()) { 787 exit(1); 788 } 789 trace_init_file(trace_file); 790 qemu_set_log(LOG_TRACE); 791 792 socket_activation = check_socket_activation(); 793 if (socket_activation == 0) { 794 setup_address_and_port(&bindto, &port); 795 } else { 796 /* Using socket activation - check user didn't use -p etc. */ 797 const char *err_msg = socket_activation_validate_opts(device, sockpath, 798 bindto, port); 799 if (err_msg != NULL) { 800 error_report("%s", err_msg); 801 exit(EXIT_FAILURE); 802 } 803 804 /* qemu-nbd can only listen on a single socket. */ 805 if (socket_activation > 1) { 806 error_report("qemu-nbd does not support socket activation with %s > 1", 807 "LISTEN_FDS"); 808 exit(EXIT_FAILURE); 809 } 810 } 811 812 if (tlscredsid) { 813 if (sockpath) { 814 error_report("TLS is only supported with IPv4/IPv6"); 815 exit(EXIT_FAILURE); 816 } 817 if (device) { 818 error_report("TLS is not supported with a host device"); 819 exit(EXIT_FAILURE); 820 } 821 if (!export_name) { 822 /* Set the default NBD protocol export name, since 823 * we *must* use new style protocol for TLS */ 824 export_name = ""; 825 } 826 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 827 if (local_err) { 828 error_report("Failed to get TLS creds %s", 829 error_get_pretty(local_err)); 830 exit(EXIT_FAILURE); 831 } 832 } 833 834 if (disconnect) { 835 int nbdfd = open(argv[optind], O_RDWR); 836 if (nbdfd < 0) { 837 error_report("Cannot open %s: %s", argv[optind], 838 strerror(errno)); 839 exit(EXIT_FAILURE); 840 } 841 nbd_disconnect(nbdfd); 842 843 close(nbdfd); 844 845 printf("%s disconnected\n", argv[optind]); 846 847 return 0; 848 } 849 850 if ((device && !verbose) || fork_process) { 851 int stderr_fd[2]; 852 pid_t pid; 853 int ret; 854 855 if (qemu_pipe(stderr_fd) < 0) { 856 error_report("Error setting up communication pipe: %s", 857 strerror(errno)); 858 exit(EXIT_FAILURE); 859 } 860 861 /* Now daemonize, but keep a communication channel open to 862 * print errors and exit with the proper status code. 863 */ 864 pid = fork(); 865 if (pid < 0) { 866 error_report("Failed to fork: %s", strerror(errno)); 867 exit(EXIT_FAILURE); 868 } else if (pid == 0) { 869 close(stderr_fd[0]); 870 ret = qemu_daemon(1, 0); 871 872 /* Temporarily redirect stderr to the parent's pipe... */ 873 old_stderr = dup(STDERR_FILENO); 874 dup2(stderr_fd[1], STDERR_FILENO); 875 if (ret < 0) { 876 error_report("Failed to daemonize: %s", strerror(errno)); 877 exit(EXIT_FAILURE); 878 } 879 880 /* ... close the descriptor we inherited and go on. */ 881 close(stderr_fd[1]); 882 } else { 883 bool errors = false; 884 char *buf; 885 886 /* In the parent. Print error messages from the child until 887 * it closes the pipe. 888 */ 889 close(stderr_fd[1]); 890 buf = g_malloc(1024); 891 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 892 errors = true; 893 ret = qemu_write_full(STDERR_FILENO, buf, ret); 894 if (ret < 0) { 895 exit(EXIT_FAILURE); 896 } 897 } 898 if (ret < 0) { 899 error_report("Cannot read from daemon: %s", 900 strerror(errno)); 901 exit(EXIT_FAILURE); 902 } 903 904 /* Usually the daemon should not print any message. 905 * Exit with zero status in that case. 906 */ 907 exit(errors); 908 } 909 } 910 911 if (device != NULL && sockpath == NULL) { 912 sockpath = g_malloc(128); 913 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 914 } 915 916 if (socket_activation == 0) { 917 server_ioc = qio_channel_socket_new(); 918 saddr = nbd_build_socket_address(sockpath, bindto, port); 919 if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) { 920 object_unref(OBJECT(server_ioc)); 921 error_report_err(local_err); 922 return 1; 923 } 924 } else { 925 /* See comment in check_socket_activation above. */ 926 assert(socket_activation == 1); 927 server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD, 928 &local_err); 929 if (server_ioc == NULL) { 930 error_report("Failed to use socket activation: %s", 931 error_get_pretty(local_err)); 932 exit(EXIT_FAILURE); 933 } 934 } 935 936 if (qemu_init_main_loop(&local_err)) { 937 error_report_err(local_err); 938 exit(EXIT_FAILURE); 939 } 940 bdrv_init(); 941 atexit(bdrv_close_all); 942 943 srcpath = argv[optind]; 944 if (imageOpts) { 945 QemuOpts *opts; 946 if (fmt) { 947 error_report("--image-opts and -f are mutually exclusive"); 948 exit(EXIT_FAILURE); 949 } 950 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 951 if (!opts) { 952 qemu_opts_reset(&file_opts); 953 exit(EXIT_FAILURE); 954 } 955 options = qemu_opts_to_qdict(opts, NULL); 956 qemu_opts_reset(&file_opts); 957 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 958 } else { 959 if (fmt) { 960 options = qdict_new(); 961 qdict_put_str(options, "driver", fmt); 962 } 963 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 964 } 965 966 if (!blk) { 967 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 968 argv[optind]); 969 exit(EXIT_FAILURE); 970 } 971 bs = blk_bs(blk); 972 973 blk_set_enable_write_cache(blk, !writethrough); 974 975 if (sn_opts) { 976 ret = bdrv_snapshot_load_tmp(bs, 977 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 978 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 979 &local_err); 980 } else if (sn_id_or_name) { 981 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 982 &local_err); 983 } 984 if (ret < 0) { 985 error_reportf_err(local_err, "Failed to load snapshot: "); 986 exit(EXIT_FAILURE); 987 } 988 989 bs->detect_zeroes = detect_zeroes; 990 fd_size = blk_getlength(blk); 991 if (fd_size < 0) { 992 error_report("Failed to determine the image length: %s", 993 strerror(-fd_size)); 994 exit(EXIT_FAILURE); 995 } 996 997 if (dev_offset >= fd_size) { 998 error_report("Offset (%lld) has to be smaller than the image size " 999 "(%lld)", 1000 (long long int)dev_offset, (long long int)fd_size); 1001 exit(EXIT_FAILURE); 1002 } 1003 fd_size -= dev_offset; 1004 1005 if (partition != -1) { 1006 ret = find_partition(blk, partition, &dev_offset, &fd_size); 1007 if (ret < 0) { 1008 error_report("Could not find partition %d: %s", partition, 1009 strerror(-ret)); 1010 exit(EXIT_FAILURE); 1011 } 1012 } 1013 1014 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1015 writethrough, NULL, &local_err); 1016 if (!exp) { 1017 error_report_err(local_err); 1018 exit(EXIT_FAILURE); 1019 } 1020 if (export_name) { 1021 nbd_export_set_name(exp, export_name); 1022 nbd_export_set_description(exp, export_description); 1023 newproto = true; 1024 } else if (export_description) { 1025 error_report("Export description requires an export name"); 1026 exit(EXIT_FAILURE); 1027 } 1028 1029 if (device) { 1030 int ret; 1031 1032 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1033 if (ret != 0) { 1034 error_report("Failed to create client thread: %s", strerror(ret)); 1035 exit(EXIT_FAILURE); 1036 } 1037 } else { 1038 /* Shut up GCC warnings. */ 1039 memset(&client_thread, 0, sizeof(client_thread)); 1040 } 1041 1042 nbd_update_server_watch(); 1043 1044 /* now when the initialization is (almost) complete, chdir("/") 1045 * to free any busy filesystems */ 1046 if (chdir("/") < 0) { 1047 error_report("Could not chdir to root directory: %s", 1048 strerror(errno)); 1049 exit(EXIT_FAILURE); 1050 } 1051 1052 if (fork_process) { 1053 dup2(old_stderr, STDERR_FILENO); 1054 close(old_stderr); 1055 } 1056 1057 state = RUNNING; 1058 do { 1059 main_loop_wait(false); 1060 if (state == TERMINATE) { 1061 state = TERMINATING; 1062 nbd_export_close(exp); 1063 nbd_export_put(exp); 1064 exp = NULL; 1065 } 1066 } while (state != TERMINATED); 1067 1068 blk_unref(blk); 1069 if (sockpath) { 1070 unlink(sockpath); 1071 } 1072 1073 qemu_opts_del(sn_opts); 1074 1075 if (device) { 1076 void *ret; 1077 pthread_join(client_thread, &ret); 1078 exit(ret != NULL); 1079 } else { 1080 exit(EXIT_SUCCESS); 1081 } 1082 } 1083