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 "qemu-common.h" 25 #include "qapi/error.h" 26 #include "qemu/cutils.h" 27 #include "sysemu/block-backend.h" 28 #include "sysemu/runstate.h" /* for qemu_system_killed() prototype */ 29 #include "block/block_int.h" 30 #include "block/nbd.h" 31 #include "qemu/main-loop.h" 32 #include "qemu/module.h" 33 #include "qemu/option.h" 34 #include "qemu/error-report.h" 35 #include "qemu/config-file.h" 36 #include "qemu/bswap.h" 37 #include "qemu/log.h" 38 #include "qemu/systemd.h" 39 #include "block/snapshot.h" 40 #include "qapi/qmp/qdict.h" 41 #include "qapi/qmp/qstring.h" 42 #include "qom/object_interfaces.h" 43 #include "io/channel-socket.h" 44 #include "io/net-listener.h" 45 #include "crypto/init.h" 46 #include "trace/control.h" 47 #include "qemu-version.h" 48 49 #ifdef __linux__ 50 #define HAVE_NBD_DEVICE 1 51 #else 52 #define HAVE_NBD_DEVICE 0 53 #endif 54 55 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 56 #define QEMU_NBD_OPT_CACHE 256 57 #define QEMU_NBD_OPT_AIO 257 58 #define QEMU_NBD_OPT_DISCARD 258 59 #define QEMU_NBD_OPT_DETECT_ZEROES 259 60 #define QEMU_NBD_OPT_OBJECT 260 61 #define QEMU_NBD_OPT_TLSCREDS 261 62 #define QEMU_NBD_OPT_IMAGE_OPTS 262 63 #define QEMU_NBD_OPT_FORK 263 64 #define QEMU_NBD_OPT_TLSAUTHZ 264 65 #define QEMU_NBD_OPT_PID_FILE 265 66 67 #define MBR_SIZE 512 68 69 static int verbose; 70 static char *srcpath; 71 static SocketAddress *saddr; 72 static int persistent = 0; 73 static enum { RUNNING, TERMINATE, TERMINATED } state; 74 static int shared = 1; 75 static int nb_fds; 76 static QIONetListener *server; 77 static QCryptoTLSCreds *tlscreds; 78 static const char *tlsauthz; 79 80 static void usage(const char *name) 81 { 82 (printf) ( 83 "Usage: %s [OPTIONS] FILE\n" 84 " or: %s -L [OPTIONS]\n" 85 "QEMU Disk Network Block Device Utility\n" 86 "\n" 87 " -h, --help display this help and exit\n" 88 " -V, --version output version information and exit\n" 89 "\n" 90 "Connection properties:\n" 91 " -p, --port=PORT port to listen on (default `%d')\n" 92 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 93 " -k, --socket=PATH path to the unix socket\n" 94 " (default '"SOCKET_PATH"')\n" 95 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 96 " -t, --persistent don't exit on the last connection\n" 97 " -v, --verbose display extra debugging information\n" 98 " -x, --export-name=NAME expose export by name (default is empty string)\n" 99 " -D, --description=TEXT export a human-readable description\n" 100 "\n" 101 "Exposing part of the image:\n" 102 " -o, --offset=OFFSET offset into the image\n" 103 " -A, --allocation-depth expose the allocation depth\n" 104 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 105 "\n" 106 "General purpose options:\n" 107 " -L, --list list exports available from another NBD server\n" 108 " --object type,id=ID,... define an object such as 'secret' for providing\n" 109 " passwords and/or encryption keys\n" 110 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 111 " --tls-authz=ID use id of an earlier --object to provide\n" 112 " authorization\n" 113 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 114 " specify tracing options\n" 115 " --fork fork off the server process and exit the parent\n" 116 " once the server is running\n" 117 " --pid-file=PATH store the server's process ID in the given file\n" 118 #if HAVE_NBD_DEVICE 119 "\n" 120 "Kernel NBD client support:\n" 121 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 122 " -d, --disconnect disconnect the specified device\n" 123 #endif 124 "\n" 125 "Block device options:\n" 126 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 127 " -r, --read-only export read-only\n" 128 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 129 " file with backing_file=FILE, redirect the write to\n" 130 " the temporary one\n" 131 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 132 " load an internal snapshot inside FILE and export it\n" 133 " as an read-only device, SNAPSHOT_PARAM format is\n" 134 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 135 " '[ID_OR_NAME]'\n" 136 " -n, --nocache disable host cache\n" 137 " --cache=MODE set cache mode (none, writeback, ...)\n" 138 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 139 " --discard=MODE set discard mode (ignore, unmap)\n" 140 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 141 " --image-opts treat FILE as a full set of image options\n" 142 "\n" 143 QEMU_HELP_BOTTOM "\n" 144 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 145 } 146 147 static void version(const char *name) 148 { 149 printf( 150 "%s " QEMU_FULL_VERSION "\n" 151 "Written by Anthony Liguori.\n" 152 "\n" 153 QEMU_COPYRIGHT "\n" 154 "This is free software; see the source for copying conditions. There is NO\n" 155 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 156 , name); 157 } 158 159 #ifdef CONFIG_POSIX 160 /* 161 * The client thread uses SIGTERM to interrupt the server. A signal 162 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 163 */ 164 void qemu_system_killed(int signum, pid_t pid) 165 { 166 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 167 qemu_notify_event(); 168 } 169 #endif /* CONFIG_POSIX */ 170 171 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 172 const char *hostname) 173 { 174 int ret = EXIT_FAILURE; 175 int rc; 176 Error *err = NULL; 177 QIOChannelSocket *sioc; 178 NBDExportInfo *list; 179 int i, j; 180 181 sioc = qio_channel_socket_new(); 182 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 183 error_report_err(err); 184 goto out; 185 } 186 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 187 &err); 188 if (rc < 0) { 189 if (err) { 190 error_report_err(err); 191 } 192 goto out; 193 } 194 printf("exports available: %d\n", rc); 195 for (i = 0; i < rc; i++) { 196 printf(" export: '%s'\n", list[i].name); 197 if (list[i].description && *list[i].description) { 198 printf(" description: %s\n", list[i].description); 199 } 200 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 201 static const char *const flag_names[] = { 202 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 203 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 204 [NBD_FLAG_SEND_FUA_BIT] = "fua", 205 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 206 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 207 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 208 [NBD_FLAG_SEND_DF_BIT] = "df", 209 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 210 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 211 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 212 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 213 }; 214 215 printf(" size: %" PRIu64 "\n", list[i].size); 216 printf(" flags: 0x%x (", list[i].flags); 217 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 218 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 219 printf(" %s", flag_names[bit]); 220 } 221 } 222 printf(" )\n"); 223 } 224 if (list[i].min_block) { 225 printf(" min block: %u\n", list[i].min_block); 226 printf(" opt block: %u\n", list[i].opt_block); 227 printf(" max block: %u\n", list[i].max_block); 228 } 229 if (list[i].n_contexts) { 230 printf(" available meta contexts: %d\n", list[i].n_contexts); 231 for (j = 0; j < list[i].n_contexts; j++) { 232 printf(" %s\n", list[i].contexts[j]); 233 } 234 } 235 } 236 nbd_free_export_list(list, rc); 237 238 ret = EXIT_SUCCESS; 239 out: 240 object_unref(OBJECT(sioc)); 241 return ret; 242 } 243 244 245 #if HAVE_NBD_DEVICE 246 static void *show_parts(void *arg) 247 { 248 char *device = arg; 249 int nbd; 250 251 /* linux just needs an open() to trigger 252 * the partition table update 253 * but remember to load the module with max_part != 0 : 254 * modprobe nbd max_part=63 255 */ 256 nbd = open(device, O_RDWR); 257 if (nbd >= 0) { 258 close(nbd); 259 } 260 return NULL; 261 } 262 263 static void *nbd_client_thread(void *arg) 264 { 265 char *device = arg; 266 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 267 QIOChannelSocket *sioc; 268 int fd = -1; 269 int ret = EXIT_FAILURE; 270 pthread_t show_parts_thread; 271 Error *local_error = NULL; 272 273 sioc = qio_channel_socket_new(); 274 if (qio_channel_socket_connect_sync(sioc, 275 saddr, 276 &local_error) < 0) { 277 error_report_err(local_error); 278 goto out; 279 } 280 281 if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 282 NULL, NULL, NULL, &info, &local_error) < 0) { 283 if (local_error) { 284 error_report_err(local_error); 285 } 286 goto out; 287 } 288 289 fd = open(device, O_RDWR); 290 if (fd < 0) { 291 /* Linux-only, we can use %m in printf. */ 292 error_report("Failed to open %s: %m", device); 293 goto out; 294 } 295 296 if (nbd_init(fd, sioc, &info, &local_error) < 0) { 297 error_report_err(local_error); 298 goto out; 299 } 300 301 /* update partition table */ 302 pthread_create(&show_parts_thread, NULL, show_parts, device); 303 304 if (verbose) { 305 fprintf(stderr, "NBD device %s is now connected to %s\n", 306 device, srcpath); 307 } else { 308 /* Close stderr so that the qemu-nbd process exits. */ 309 dup2(STDOUT_FILENO, STDERR_FILENO); 310 } 311 312 if (nbd_client(fd) < 0) { 313 goto out; 314 } 315 316 ret = EXIT_SUCCESS; 317 318 out: 319 if (fd >= 0) { 320 close(fd); 321 } 322 object_unref(OBJECT(sioc)); 323 g_free(info.name); 324 kill(getpid(), SIGTERM); 325 return (void *) (intptr_t) ret; 326 } 327 #endif /* HAVE_NBD_DEVICE */ 328 329 static int nbd_can_accept(void) 330 { 331 return state == RUNNING && nb_fds < shared; 332 } 333 334 static void nbd_update_server_watch(void); 335 336 static void nbd_client_closed(NBDClient *client, bool negotiated) 337 { 338 nb_fds--; 339 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 340 state = TERMINATE; 341 } 342 nbd_update_server_watch(); 343 nbd_client_put(client); 344 } 345 346 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 347 gpointer opaque) 348 { 349 if (state >= TERMINATE) { 350 return; 351 } 352 353 nb_fds++; 354 nbd_update_server_watch(); 355 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 356 } 357 358 static void nbd_update_server_watch(void) 359 { 360 if (nbd_can_accept()) { 361 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 362 } else { 363 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 364 } 365 } 366 367 368 static SocketAddress *nbd_build_socket_address(const char *sockpath, 369 const char *bindto, 370 const char *port) 371 { 372 SocketAddress *saddr; 373 374 saddr = g_new0(SocketAddress, 1); 375 if (sockpath) { 376 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 377 saddr->u.q_unix.path = g_strdup(sockpath); 378 } else { 379 InetSocketAddress *inet; 380 saddr->type = SOCKET_ADDRESS_TYPE_INET; 381 inet = &saddr->u.inet; 382 inet->host = g_strdup(bindto); 383 if (port) { 384 inet->port = g_strdup(port); 385 } else { 386 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 387 } 388 } 389 390 return saddr; 391 } 392 393 394 static QemuOptsList file_opts = { 395 .name = "file", 396 .implied_opt_name = "file", 397 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 398 .desc = { 399 /* no elements => accept any params */ 400 { /* end of list */ } 401 }, 402 }; 403 404 static QemuOptsList qemu_object_opts = { 405 .name = "object", 406 .implied_opt_name = "qom-type", 407 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 408 .desc = { 409 { } 410 }, 411 }; 412 413 static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts) 414 { 415 if (user_creatable_print_help(type, opts)) { 416 exit(0); 417 } 418 return true; 419 } 420 421 422 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 423 Error **errp) 424 { 425 Object *obj; 426 QCryptoTLSCreds *creds; 427 428 obj = object_resolve_path_component( 429 object_get_objects_root(), id); 430 if (!obj) { 431 error_setg(errp, "No TLS credentials with id '%s'", 432 id); 433 return NULL; 434 } 435 creds = (QCryptoTLSCreds *) 436 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 437 if (!creds) { 438 error_setg(errp, "Object with id '%s' is not TLS credentials", 439 id); 440 return NULL; 441 } 442 443 if (list) { 444 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 445 error_setg(errp, 446 "Expecting TLS credentials with a client endpoint"); 447 return NULL; 448 } 449 } else { 450 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 451 error_setg(errp, 452 "Expecting TLS credentials with a server endpoint"); 453 return NULL; 454 } 455 } 456 object_ref(obj); 457 return creds; 458 } 459 460 static void setup_address_and_port(const char **address, const char **port) 461 { 462 if (*address == NULL) { 463 *address = "0.0.0.0"; 464 } 465 466 if (*port == NULL) { 467 *port = stringify(NBD_DEFAULT_PORT); 468 } 469 } 470 471 /* 472 * Check socket parameters compatibility when socket activation is used. 473 */ 474 static const char *socket_activation_validate_opts(const char *device, 475 const char *sockpath, 476 const char *address, 477 const char *port, 478 bool list) 479 { 480 if (device != NULL) { 481 return "NBD device can't be set when using socket activation"; 482 } 483 484 if (sockpath != NULL) { 485 return "Unix socket can't be set when using socket activation"; 486 } 487 488 if (address != NULL) { 489 return "The interface can't be set when using socket activation"; 490 } 491 492 if (port != NULL) { 493 return "TCP port number can't be set when using socket activation"; 494 } 495 496 if (list) { 497 return "List mode is incompatible with socket activation"; 498 } 499 500 return NULL; 501 } 502 503 static void qemu_nbd_shutdown(void) 504 { 505 job_cancel_sync_all(); 506 bdrv_close_all(); 507 } 508 509 int main(int argc, char **argv) 510 { 511 BlockBackend *blk; 512 BlockDriverState *bs; 513 uint64_t dev_offset = 0; 514 bool readonly = false; 515 bool disconnect = false; 516 const char *bindto = NULL; 517 const char *port = NULL; 518 char *sockpath = NULL; 519 char *device = NULL; 520 QemuOpts *sn_opts = NULL; 521 const char *sn_id_or_name = NULL; 522 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 523 struct option lopt[] = { 524 { "help", no_argument, NULL, 'h' }, 525 { "version", no_argument, NULL, 'V' }, 526 { "bind", required_argument, NULL, 'b' }, 527 { "port", required_argument, NULL, 'p' }, 528 { "socket", required_argument, NULL, 'k' }, 529 { "offset", required_argument, NULL, 'o' }, 530 { "read-only", no_argument, NULL, 'r' }, 531 { "allocation-depth", no_argument, NULL, 'A' }, 532 { "bitmap", required_argument, NULL, 'B' }, 533 { "connect", required_argument, NULL, 'c' }, 534 { "disconnect", no_argument, NULL, 'd' }, 535 { "list", no_argument, NULL, 'L' }, 536 { "snapshot", no_argument, NULL, 's' }, 537 { "load-snapshot", required_argument, NULL, 'l' }, 538 { "nocache", no_argument, NULL, 'n' }, 539 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 540 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 541 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 542 { "detect-zeroes", required_argument, NULL, 543 QEMU_NBD_OPT_DETECT_ZEROES }, 544 { "shared", required_argument, NULL, 'e' }, 545 { "format", required_argument, NULL, 'f' }, 546 { "persistent", no_argument, NULL, 't' }, 547 { "verbose", no_argument, NULL, 'v' }, 548 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 549 { "export-name", required_argument, NULL, 'x' }, 550 { "description", required_argument, NULL, 'D' }, 551 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 552 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 553 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 554 { "trace", required_argument, NULL, 'T' }, 555 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 556 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 557 { NULL, 0, NULL, 0 } 558 }; 559 int ch; 560 int opt_ind = 0; 561 int flags = BDRV_O_RDWR; 562 int ret = 0; 563 bool seen_cache = false; 564 bool seen_discard = false; 565 bool seen_aio = false; 566 pthread_t client_thread; 567 const char *fmt = NULL; 568 Error *local_err = NULL; 569 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 570 QDict *options = NULL; 571 const char *export_name = NULL; /* defaults to "" later for server mode */ 572 const char *export_description = NULL; 573 strList *bitmaps = NULL; 574 bool alloc_depth = false; 575 const char *tlscredsid = NULL; 576 bool imageOpts = false; 577 bool writethrough = true; 578 bool fork_process = false; 579 bool list = false; 580 int old_stderr = -1; 581 unsigned socket_activation; 582 const char *pid_file_name = NULL; 583 BlockExportOptions *export_opts; 584 585 #ifdef CONFIG_POSIX 586 os_setup_early_signal_handling(); 587 os_setup_signal_handling(); 588 #endif 589 590 socket_init(); 591 error_init(argv[0]); 592 module_call_init(MODULE_INIT_TRACE); 593 qcrypto_init(&error_fatal); 594 595 module_call_init(MODULE_INIT_QOM); 596 qemu_add_opts(&qemu_object_opts); 597 qemu_add_opts(&qemu_trace_opts); 598 qemu_init_exec_dir(argv[0]); 599 600 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 601 switch (ch) { 602 case 's': 603 flags |= BDRV_O_SNAPSHOT; 604 break; 605 case 'n': 606 optarg = (char *) "none"; 607 /* fallthrough */ 608 case QEMU_NBD_OPT_CACHE: 609 if (seen_cache) { 610 error_report("-n and --cache can only be specified once"); 611 exit(EXIT_FAILURE); 612 } 613 seen_cache = true; 614 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 615 error_report("Invalid cache mode `%s'", optarg); 616 exit(EXIT_FAILURE); 617 } 618 break; 619 case QEMU_NBD_OPT_AIO: 620 if (seen_aio) { 621 error_report("--aio can only be specified once"); 622 exit(EXIT_FAILURE); 623 } 624 seen_aio = true; 625 if (bdrv_parse_aio(optarg, &flags) < 0) { 626 error_report("Invalid aio mode '%s'", optarg); 627 exit(EXIT_FAILURE); 628 } 629 break; 630 case QEMU_NBD_OPT_DISCARD: 631 if (seen_discard) { 632 error_report("--discard can only be specified once"); 633 exit(EXIT_FAILURE); 634 } 635 seen_discard = true; 636 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 637 error_report("Invalid discard mode `%s'", optarg); 638 exit(EXIT_FAILURE); 639 } 640 break; 641 case QEMU_NBD_OPT_DETECT_ZEROES: 642 detect_zeroes = 643 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 644 optarg, 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 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 667 error_report("Invalid offset '%s'", optarg); 668 exit(EXIT_FAILURE); 669 } 670 break; 671 case 'l': 672 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 673 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 674 optarg, false); 675 if (!sn_opts) { 676 error_report("Failed in parsing snapshot param `%s'", 677 optarg); 678 exit(EXIT_FAILURE); 679 } 680 } else { 681 sn_id_or_name = optarg; 682 } 683 /* fall through */ 684 case 'r': 685 readonly = true; 686 flags &= ~BDRV_O_RDWR; 687 break; 688 case 'A': 689 alloc_depth = true; 690 break; 691 case 'B': 692 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg)); 693 break; 694 case 'k': 695 sockpath = optarg; 696 if (sockpath[0] != '/') { 697 error_report("socket path must be absolute"); 698 exit(EXIT_FAILURE); 699 } 700 break; 701 case 'd': 702 disconnect = true; 703 break; 704 case 'c': 705 device = optarg; 706 break; 707 case 'e': 708 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 709 shared < 1) { 710 error_report("Invalid shared device number '%s'", optarg); 711 exit(EXIT_FAILURE); 712 } 713 break; 714 case 'f': 715 fmt = optarg; 716 break; 717 case 't': 718 persistent = 1; 719 break; 720 case 'x': 721 export_name = optarg; 722 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 723 error_report("export name '%s' too long", export_name); 724 exit(EXIT_FAILURE); 725 } 726 break; 727 case 'D': 728 export_description = optarg; 729 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 730 error_report("export description '%s' too long", 731 export_description); 732 exit(EXIT_FAILURE); 733 } 734 break; 735 case 'v': 736 verbose = 1; 737 break; 738 case 'V': 739 version(argv[0]); 740 exit(0); 741 break; 742 case 'h': 743 usage(argv[0]); 744 exit(0); 745 break; 746 case '?': 747 error_report("Try `%s --help' for more information.", argv[0]); 748 exit(EXIT_FAILURE); 749 case QEMU_NBD_OPT_OBJECT: { 750 QemuOpts *opts; 751 opts = qemu_opts_parse_noisily(&qemu_object_opts, 752 optarg, true); 753 if (!opts) { 754 exit(EXIT_FAILURE); 755 } 756 } break; 757 case QEMU_NBD_OPT_TLSCREDS: 758 tlscredsid = optarg; 759 break; 760 case QEMU_NBD_OPT_IMAGE_OPTS: 761 imageOpts = true; 762 break; 763 case 'T': 764 trace_opt_parse(optarg); 765 break; 766 case QEMU_NBD_OPT_TLSAUTHZ: 767 tlsauthz = optarg; 768 break; 769 case QEMU_NBD_OPT_FORK: 770 fork_process = true; 771 break; 772 case 'L': 773 list = true; 774 break; 775 case QEMU_NBD_OPT_PID_FILE: 776 pid_file_name = optarg; 777 break; 778 } 779 } 780 781 if (list) { 782 if (argc != optind) { 783 error_report("List mode is incompatible with a file name"); 784 exit(EXIT_FAILURE); 785 } 786 if (export_name || export_description || dev_offset || 787 device || disconnect || fmt || sn_id_or_name || bitmaps || 788 alloc_depth || seen_aio || seen_discard || seen_cache) { 789 error_report("List mode is incompatible with per-device settings"); 790 exit(EXIT_FAILURE); 791 } 792 if (fork_process) { 793 error_report("List mode is incompatible with forking"); 794 exit(EXIT_FAILURE); 795 } 796 } else if ((argc - optind) != 1) { 797 error_report("Invalid number of arguments"); 798 error_printf("Try `%s --help' for more information.\n", argv[0]); 799 exit(EXIT_FAILURE); 800 } else if (!export_name) { 801 export_name = ""; 802 } 803 804 qemu_opts_foreach(&qemu_object_opts, 805 user_creatable_add_opts_foreach, 806 qemu_nbd_object_print_help, &error_fatal); 807 808 if (!trace_init_backends()) { 809 exit(1); 810 } 811 trace_init_file(); 812 qemu_set_log(LOG_TRACE); 813 814 socket_activation = check_socket_activation(); 815 if (socket_activation == 0) { 816 setup_address_and_port(&bindto, &port); 817 } else { 818 /* Using socket activation - check user didn't use -p etc. */ 819 const char *err_msg = socket_activation_validate_opts(device, sockpath, 820 bindto, port, 821 list); 822 if (err_msg != NULL) { 823 error_report("%s", err_msg); 824 exit(EXIT_FAILURE); 825 } 826 827 /* qemu-nbd can only listen on a single socket. */ 828 if (socket_activation > 1) { 829 error_report("qemu-nbd does not support socket activation with %s > 1", 830 "LISTEN_FDS"); 831 exit(EXIT_FAILURE); 832 } 833 } 834 835 if (tlscredsid) { 836 if (sockpath) { 837 error_report("TLS is only supported with IPv4/IPv6"); 838 exit(EXIT_FAILURE); 839 } 840 if (device) { 841 error_report("TLS is not supported with a host device"); 842 exit(EXIT_FAILURE); 843 } 844 if (tlsauthz && list) { 845 error_report("TLS authorization is incompatible with export list"); 846 exit(EXIT_FAILURE); 847 } 848 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 849 if (local_err) { 850 error_reportf_err(local_err, "Failed to get TLS creds: "); 851 exit(EXIT_FAILURE); 852 } 853 } else { 854 if (tlsauthz) { 855 error_report("--tls-authz is not permitted without --tls-creds"); 856 exit(EXIT_FAILURE); 857 } 858 } 859 860 if (list) { 861 saddr = nbd_build_socket_address(sockpath, bindto, port); 862 return qemu_nbd_client_list(saddr, tlscreds, bindto); 863 } 864 865 #if !HAVE_NBD_DEVICE 866 if (disconnect || device) { 867 error_report("Kernel /dev/nbdN support not available"); 868 exit(EXIT_FAILURE); 869 } 870 #else /* HAVE_NBD_DEVICE */ 871 if (disconnect) { 872 int nbdfd = open(argv[optind], O_RDWR); 873 if (nbdfd < 0) { 874 error_report("Cannot open %s: %s", argv[optind], 875 strerror(errno)); 876 exit(EXIT_FAILURE); 877 } 878 nbd_disconnect(nbdfd); 879 880 close(nbdfd); 881 882 printf("%s disconnected\n", argv[optind]); 883 884 return 0; 885 } 886 #endif 887 888 if ((device && !verbose) || fork_process) { 889 #ifndef WIN32 890 int stderr_fd[2]; 891 pid_t pid; 892 int ret; 893 894 if (qemu_pipe(stderr_fd) < 0) { 895 error_report("Error setting up communication pipe: %s", 896 strerror(errno)); 897 exit(EXIT_FAILURE); 898 } 899 900 /* Now daemonize, but keep a communication channel open to 901 * print errors and exit with the proper status code. 902 */ 903 pid = fork(); 904 if (pid < 0) { 905 error_report("Failed to fork: %s", strerror(errno)); 906 exit(EXIT_FAILURE); 907 } else if (pid == 0) { 908 close(stderr_fd[0]); 909 910 /* Remember parent's stderr if we will be restoring it. */ 911 if (fork_process) { 912 old_stderr = dup(STDERR_FILENO); 913 } 914 915 ret = qemu_daemon(1, 0); 916 917 /* Temporarily redirect stderr to the parent's pipe... */ 918 dup2(stderr_fd[1], STDERR_FILENO); 919 if (ret < 0) { 920 error_report("Failed to daemonize: %s", strerror(errno)); 921 exit(EXIT_FAILURE); 922 } 923 924 /* ... close the descriptor we inherited and go on. */ 925 close(stderr_fd[1]); 926 } else { 927 bool errors = false; 928 char *buf; 929 930 /* In the parent. Print error messages from the child until 931 * it closes the pipe. 932 */ 933 close(stderr_fd[1]); 934 buf = g_malloc(1024); 935 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 936 errors = true; 937 ret = qemu_write_full(STDERR_FILENO, buf, ret); 938 if (ret < 0) { 939 exit(EXIT_FAILURE); 940 } 941 } 942 if (ret < 0) { 943 error_report("Cannot read from daemon: %s", 944 strerror(errno)); 945 exit(EXIT_FAILURE); 946 } 947 948 /* Usually the daemon should not print any message. 949 * Exit with zero status in that case. 950 */ 951 exit(errors); 952 } 953 #else /* WIN32 */ 954 error_report("Unable to fork into background on Windows hosts"); 955 exit(EXIT_FAILURE); 956 #endif /* WIN32 */ 957 } 958 959 if (device != NULL && sockpath == NULL) { 960 sockpath = g_malloc(128); 961 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 962 } 963 964 server = qio_net_listener_new(); 965 if (socket_activation == 0) { 966 saddr = nbd_build_socket_address(sockpath, bindto, port); 967 if (qio_net_listener_open_sync(server, saddr, 1, &local_err) < 0) { 968 object_unref(OBJECT(server)); 969 error_report_err(local_err); 970 exit(EXIT_FAILURE); 971 } 972 } else { 973 size_t i; 974 /* See comment in check_socket_activation above. */ 975 for (i = 0; i < socket_activation; i++) { 976 QIOChannelSocket *sioc; 977 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 978 &local_err); 979 if (sioc == NULL) { 980 object_unref(OBJECT(server)); 981 error_reportf_err(local_err, 982 "Failed to use socket activation: "); 983 exit(EXIT_FAILURE); 984 } 985 qio_net_listener_add(server, sioc); 986 object_unref(OBJECT(sioc)); 987 } 988 } 989 990 if (qemu_init_main_loop(&local_err)) { 991 error_report_err(local_err); 992 exit(EXIT_FAILURE); 993 } 994 bdrv_init(); 995 atexit(qemu_nbd_shutdown); 996 997 srcpath = argv[optind]; 998 if (imageOpts) { 999 QemuOpts *opts; 1000 if (fmt) { 1001 error_report("--image-opts and -f are mutually exclusive"); 1002 exit(EXIT_FAILURE); 1003 } 1004 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1005 if (!opts) { 1006 qemu_opts_reset(&file_opts); 1007 exit(EXIT_FAILURE); 1008 } 1009 options = qemu_opts_to_qdict(opts, NULL); 1010 qemu_opts_reset(&file_opts); 1011 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1012 } else { 1013 if (fmt) { 1014 options = qdict_new(); 1015 qdict_put_str(options, "driver", fmt); 1016 } 1017 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1018 } 1019 1020 if (!blk) { 1021 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1022 argv[optind]); 1023 exit(EXIT_FAILURE); 1024 } 1025 bs = blk_bs(blk); 1026 1027 if (dev_offset) { 1028 QDict *raw_opts = qdict_new(); 1029 qdict_put_str(raw_opts, "driver", "raw"); 1030 qdict_put_str(raw_opts, "file", bs->node_name); 1031 qdict_put_int(raw_opts, "offset", dev_offset); 1032 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1033 blk_remove_bs(blk); 1034 blk_insert_bs(blk, bs, &error_fatal); 1035 bdrv_unref(bs); 1036 } 1037 1038 blk_set_enable_write_cache(blk, !writethrough); 1039 1040 if (sn_opts) { 1041 ret = bdrv_snapshot_load_tmp(bs, 1042 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1043 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1044 &local_err); 1045 } else if (sn_id_or_name) { 1046 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1047 &local_err); 1048 } 1049 if (ret < 0) { 1050 error_reportf_err(local_err, "Failed to load snapshot: "); 1051 exit(EXIT_FAILURE); 1052 } 1053 1054 bs->detect_zeroes = detect_zeroes; 1055 1056 nbd_server_is_qemu_nbd(true); 1057 1058 export_opts = g_new(BlockExportOptions, 1); 1059 *export_opts = (BlockExportOptions) { 1060 .type = BLOCK_EXPORT_TYPE_NBD, 1061 .id = g_strdup("qemu-nbd-export"), 1062 .node_name = g_strdup(bdrv_get_node_name(bs)), 1063 .has_writethrough = true, 1064 .writethrough = writethrough, 1065 .has_writable = true, 1066 .writable = !readonly, 1067 .u.nbd = { 1068 .has_name = true, 1069 .name = g_strdup(export_name), 1070 .has_description = !!export_description, 1071 .description = g_strdup(export_description), 1072 .has_bitmaps = !!bitmaps, 1073 .bitmaps = bitmaps, 1074 .has_allocation_depth = alloc_depth, 1075 .allocation_depth = alloc_depth, 1076 }, 1077 }; 1078 blk_exp_add(export_opts, &error_fatal); 1079 qapi_free_BlockExportOptions(export_opts); 1080 1081 if (device) { 1082 #if HAVE_NBD_DEVICE 1083 int ret; 1084 1085 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1086 if (ret != 0) { 1087 error_report("Failed to create client thread: %s", strerror(ret)); 1088 exit(EXIT_FAILURE); 1089 } 1090 #endif 1091 } else { 1092 /* Shut up GCC warnings. */ 1093 memset(&client_thread, 0, sizeof(client_thread)); 1094 } 1095 1096 nbd_update_server_watch(); 1097 1098 if (pid_file_name) { 1099 qemu_write_pidfile(pid_file_name, &error_fatal); 1100 } 1101 1102 /* now when the initialization is (almost) complete, chdir("/") 1103 * to free any busy filesystems */ 1104 if (chdir("/") < 0) { 1105 error_report("Could not chdir to root directory: %s", 1106 strerror(errno)); 1107 exit(EXIT_FAILURE); 1108 } 1109 1110 if (fork_process) { 1111 dup2(old_stderr, STDERR_FILENO); 1112 close(old_stderr); 1113 } 1114 1115 state = RUNNING; 1116 do { 1117 main_loop_wait(false); 1118 if (state == TERMINATE) { 1119 blk_exp_close_all(); 1120 state = TERMINATED; 1121 } 1122 } while (state != TERMINATED); 1123 1124 blk_unref(blk); 1125 if (sockpath) { 1126 unlink(sockpath); 1127 } 1128 1129 qemu_opts_del(sn_opts); 1130 1131 if (device) { 1132 void *ret; 1133 pthread_join(client_thread, &ret); 1134 exit(ret != NULL); 1135 } else { 1136 exit(EXIT_SUCCESS); 1137 } 1138 } 1139