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 && (shared == 0 || 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 QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 405 Error **errp) 406 { 407 Object *obj; 408 QCryptoTLSCreds *creds; 409 410 obj = object_resolve_path_component( 411 object_get_objects_root(), id); 412 if (!obj) { 413 error_setg(errp, "No TLS credentials with id '%s'", 414 id); 415 return NULL; 416 } 417 creds = (QCryptoTLSCreds *) 418 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 419 if (!creds) { 420 error_setg(errp, "Object with id '%s' is not TLS credentials", 421 id); 422 return NULL; 423 } 424 425 if (list) { 426 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { 427 error_setg(errp, 428 "Expecting TLS credentials with a client endpoint"); 429 return NULL; 430 } 431 } else { 432 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 433 error_setg(errp, 434 "Expecting TLS credentials with a server endpoint"); 435 return NULL; 436 } 437 } 438 object_ref(obj); 439 return creds; 440 } 441 442 static void setup_address_and_port(const char **address, const char **port) 443 { 444 if (*address == NULL) { 445 *address = "0.0.0.0"; 446 } 447 448 if (*port == NULL) { 449 *port = stringify(NBD_DEFAULT_PORT); 450 } 451 } 452 453 /* 454 * Check socket parameters compatibility when socket activation is used. 455 */ 456 static const char *socket_activation_validate_opts(const char *device, 457 const char *sockpath, 458 const char *address, 459 const char *port, 460 bool list) 461 { 462 if (device != NULL) { 463 return "NBD device can't be set when using socket activation"; 464 } 465 466 if (sockpath != NULL) { 467 return "Unix socket can't be set when using socket activation"; 468 } 469 470 if (address != NULL) { 471 return "The interface can't be set when using socket activation"; 472 } 473 474 if (port != NULL) { 475 return "TCP port number can't be set when using socket activation"; 476 } 477 478 if (list) { 479 return "List mode is incompatible with socket activation"; 480 } 481 482 return NULL; 483 } 484 485 static void qemu_nbd_shutdown(void) 486 { 487 job_cancel_sync_all(); 488 blk_exp_close_all(); 489 bdrv_close_all(); 490 } 491 492 int main(int argc, char **argv) 493 { 494 BlockBackend *blk; 495 BlockDriverState *bs; 496 uint64_t dev_offset = 0; 497 bool readonly = false; 498 bool disconnect = false; 499 const char *bindto = NULL; 500 const char *port = NULL; 501 char *sockpath = NULL; 502 char *device = NULL; 503 QemuOpts *sn_opts = NULL; 504 const char *sn_id_or_name = NULL; 505 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 506 struct option lopt[] = { 507 { "help", no_argument, NULL, 'h' }, 508 { "version", no_argument, NULL, 'V' }, 509 { "bind", required_argument, NULL, 'b' }, 510 { "port", required_argument, NULL, 'p' }, 511 { "socket", required_argument, NULL, 'k' }, 512 { "offset", required_argument, NULL, 'o' }, 513 { "read-only", no_argument, NULL, 'r' }, 514 { "allocation-depth", no_argument, NULL, 'A' }, 515 { "bitmap", required_argument, NULL, 'B' }, 516 { "connect", required_argument, NULL, 'c' }, 517 { "disconnect", no_argument, NULL, 'd' }, 518 { "list", no_argument, NULL, 'L' }, 519 { "snapshot", no_argument, NULL, 's' }, 520 { "load-snapshot", required_argument, NULL, 'l' }, 521 { "nocache", no_argument, NULL, 'n' }, 522 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 523 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 524 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 525 { "detect-zeroes", required_argument, NULL, 526 QEMU_NBD_OPT_DETECT_ZEROES }, 527 { "shared", required_argument, NULL, 'e' }, 528 { "format", required_argument, NULL, 'f' }, 529 { "persistent", no_argument, NULL, 't' }, 530 { "verbose", no_argument, NULL, 'v' }, 531 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 532 { "export-name", required_argument, NULL, 'x' }, 533 { "description", required_argument, NULL, 'D' }, 534 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 535 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 536 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 537 { "trace", required_argument, NULL, 'T' }, 538 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 539 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 540 { NULL, 0, NULL, 0 } 541 }; 542 int ch; 543 int opt_ind = 0; 544 int flags = BDRV_O_RDWR; 545 int ret = 0; 546 bool seen_cache = false; 547 bool seen_discard = false; 548 bool seen_aio = false; 549 pthread_t client_thread; 550 const char *fmt = NULL; 551 Error *local_err = NULL; 552 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 553 QDict *options = NULL; 554 const char *export_name = NULL; /* defaults to "" later for server mode */ 555 const char *export_description = NULL; 556 strList *bitmaps = NULL; 557 bool alloc_depth = false; 558 const char *tlscredsid = NULL; 559 bool imageOpts = false; 560 bool writethrough = true; 561 bool fork_process = false; 562 bool list = false; 563 int old_stderr = -1; 564 unsigned socket_activation; 565 const char *pid_file_name = NULL; 566 BlockExportOptions *export_opts; 567 568 #ifdef CONFIG_POSIX 569 os_setup_early_signal_handling(); 570 os_setup_signal_handling(); 571 #endif 572 573 socket_init(); 574 error_init(argv[0]); 575 module_call_init(MODULE_INIT_TRACE); 576 qcrypto_init(&error_fatal); 577 578 module_call_init(MODULE_INIT_QOM); 579 qemu_add_opts(&qemu_trace_opts); 580 qemu_init_exec_dir(argv[0]); 581 582 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 583 switch (ch) { 584 case 's': 585 flags |= BDRV_O_SNAPSHOT; 586 break; 587 case 'n': 588 optarg = (char *) "none"; 589 /* fallthrough */ 590 case QEMU_NBD_OPT_CACHE: 591 if (seen_cache) { 592 error_report("-n and --cache can only be specified once"); 593 exit(EXIT_FAILURE); 594 } 595 seen_cache = true; 596 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 597 error_report("Invalid cache mode `%s'", optarg); 598 exit(EXIT_FAILURE); 599 } 600 break; 601 case QEMU_NBD_OPT_AIO: 602 if (seen_aio) { 603 error_report("--aio can only be specified once"); 604 exit(EXIT_FAILURE); 605 } 606 seen_aio = true; 607 if (bdrv_parse_aio(optarg, &flags) < 0) { 608 error_report("Invalid aio mode '%s'", optarg); 609 exit(EXIT_FAILURE); 610 } 611 break; 612 case QEMU_NBD_OPT_DISCARD: 613 if (seen_discard) { 614 error_report("--discard can only be specified once"); 615 exit(EXIT_FAILURE); 616 } 617 seen_discard = true; 618 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 619 error_report("Invalid discard mode `%s'", optarg); 620 exit(EXIT_FAILURE); 621 } 622 break; 623 case QEMU_NBD_OPT_DETECT_ZEROES: 624 detect_zeroes = 625 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 626 optarg, 627 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 628 &local_err); 629 if (local_err) { 630 error_reportf_err(local_err, 631 "Failed to parse detect_zeroes mode: "); 632 exit(EXIT_FAILURE); 633 } 634 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 635 !(flags & BDRV_O_UNMAP)) { 636 error_report("setting detect-zeroes to unmap is not allowed " 637 "without setting discard operation to unmap"); 638 exit(EXIT_FAILURE); 639 } 640 break; 641 case 'b': 642 bindto = optarg; 643 break; 644 case 'p': 645 port = optarg; 646 break; 647 case 'o': 648 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 649 error_report("Invalid offset '%s'", optarg); 650 exit(EXIT_FAILURE); 651 } 652 break; 653 case 'l': 654 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 655 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 656 optarg, false); 657 if (!sn_opts) { 658 error_report("Failed in parsing snapshot param `%s'", 659 optarg); 660 exit(EXIT_FAILURE); 661 } 662 } else { 663 sn_id_or_name = optarg; 664 } 665 /* fall through */ 666 case 'r': 667 readonly = true; 668 flags &= ~BDRV_O_RDWR; 669 break; 670 case 'A': 671 alloc_depth = true; 672 break; 673 case 'B': 674 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg)); 675 break; 676 case 'k': 677 sockpath = optarg; 678 if (sockpath[0] != '/') { 679 error_report("socket path must be absolute"); 680 exit(EXIT_FAILURE); 681 } 682 break; 683 case 'd': 684 disconnect = true; 685 break; 686 case 'c': 687 device = optarg; 688 break; 689 case 'e': 690 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 691 shared < 0) { 692 error_report("Invalid shared device number '%s'", optarg); 693 exit(EXIT_FAILURE); 694 } 695 break; 696 case 'f': 697 fmt = optarg; 698 break; 699 case 't': 700 persistent = 1; 701 break; 702 case 'x': 703 export_name = optarg; 704 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 705 error_report("export name '%s' too long", export_name); 706 exit(EXIT_FAILURE); 707 } 708 break; 709 case 'D': 710 export_description = optarg; 711 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 712 error_report("export description '%s' too long", 713 export_description); 714 exit(EXIT_FAILURE); 715 } 716 break; 717 case 'v': 718 verbose = 1; 719 break; 720 case 'V': 721 version(argv[0]); 722 exit(0); 723 break; 724 case 'h': 725 usage(argv[0]); 726 exit(0); 727 break; 728 case '?': 729 error_report("Try `%s --help' for more information.", argv[0]); 730 exit(EXIT_FAILURE); 731 case QEMU_NBD_OPT_OBJECT: 732 user_creatable_process_cmdline(optarg); 733 break; 734 case QEMU_NBD_OPT_TLSCREDS: 735 tlscredsid = optarg; 736 break; 737 case QEMU_NBD_OPT_IMAGE_OPTS: 738 imageOpts = true; 739 break; 740 case 'T': 741 trace_opt_parse(optarg); 742 break; 743 case QEMU_NBD_OPT_TLSAUTHZ: 744 tlsauthz = optarg; 745 break; 746 case QEMU_NBD_OPT_FORK: 747 fork_process = true; 748 break; 749 case 'L': 750 list = true; 751 break; 752 case QEMU_NBD_OPT_PID_FILE: 753 pid_file_name = optarg; 754 break; 755 } 756 } 757 758 if (list) { 759 if (argc != optind) { 760 error_report("List mode is incompatible with a file name"); 761 exit(EXIT_FAILURE); 762 } 763 if (export_name || export_description || dev_offset || 764 device || disconnect || fmt || sn_id_or_name || bitmaps || 765 alloc_depth || seen_aio || seen_discard || seen_cache) { 766 error_report("List mode is incompatible with per-device settings"); 767 exit(EXIT_FAILURE); 768 } 769 if (fork_process) { 770 error_report("List mode is incompatible with forking"); 771 exit(EXIT_FAILURE); 772 } 773 } else if ((argc - optind) != 1) { 774 error_report("Invalid number of arguments"); 775 error_printf("Try `%s --help' for more information.\n", argv[0]); 776 exit(EXIT_FAILURE); 777 } else if (!export_name) { 778 export_name = ""; 779 } 780 781 if (!trace_init_backends()) { 782 exit(1); 783 } 784 trace_init_file(); 785 qemu_set_log(LOG_TRACE); 786 787 socket_activation = check_socket_activation(); 788 if (socket_activation == 0) { 789 setup_address_and_port(&bindto, &port); 790 } else { 791 /* Using socket activation - check user didn't use -p etc. */ 792 const char *err_msg = socket_activation_validate_opts(device, sockpath, 793 bindto, port, 794 list); 795 if (err_msg != NULL) { 796 error_report("%s", err_msg); 797 exit(EXIT_FAILURE); 798 } 799 800 /* qemu-nbd can only listen on a single socket. */ 801 if (socket_activation > 1) { 802 error_report("qemu-nbd does not support socket activation with %s > 1", 803 "LISTEN_FDS"); 804 exit(EXIT_FAILURE); 805 } 806 } 807 808 if (tlscredsid) { 809 if (sockpath) { 810 error_report("TLS is only supported with IPv4/IPv6"); 811 exit(EXIT_FAILURE); 812 } 813 if (device) { 814 error_report("TLS is not supported with a host device"); 815 exit(EXIT_FAILURE); 816 } 817 if (tlsauthz && list) { 818 error_report("TLS authorization is incompatible with export list"); 819 exit(EXIT_FAILURE); 820 } 821 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 822 if (local_err) { 823 error_reportf_err(local_err, "Failed to get TLS creds: "); 824 exit(EXIT_FAILURE); 825 } 826 } else { 827 if (tlsauthz) { 828 error_report("--tls-authz is not permitted without --tls-creds"); 829 exit(EXIT_FAILURE); 830 } 831 } 832 833 if (list) { 834 saddr = nbd_build_socket_address(sockpath, bindto, port); 835 return qemu_nbd_client_list(saddr, tlscreds, bindto); 836 } 837 838 #if !HAVE_NBD_DEVICE 839 if (disconnect || device) { 840 error_report("Kernel /dev/nbdN support not available"); 841 exit(EXIT_FAILURE); 842 } 843 #else /* HAVE_NBD_DEVICE */ 844 if (disconnect) { 845 int nbdfd = open(argv[optind], O_RDWR); 846 if (nbdfd < 0) { 847 error_report("Cannot open %s: %s", argv[optind], 848 strerror(errno)); 849 exit(EXIT_FAILURE); 850 } 851 nbd_disconnect(nbdfd); 852 853 close(nbdfd); 854 855 printf("%s disconnected\n", argv[optind]); 856 857 return 0; 858 } 859 #endif 860 861 if ((device && !verbose) || fork_process) { 862 #ifndef WIN32 863 int stderr_fd[2]; 864 pid_t pid; 865 int ret; 866 867 if (qemu_pipe(stderr_fd) < 0) { 868 error_report("Error setting up communication pipe: %s", 869 strerror(errno)); 870 exit(EXIT_FAILURE); 871 } 872 873 /* Now daemonize, but keep a communication channel open to 874 * print errors and exit with the proper status code. 875 */ 876 pid = fork(); 877 if (pid < 0) { 878 error_report("Failed to fork: %s", strerror(errno)); 879 exit(EXIT_FAILURE); 880 } else if (pid == 0) { 881 close(stderr_fd[0]); 882 883 /* Remember parent's stderr if we will be restoring it. */ 884 if (fork_process) { 885 old_stderr = dup(STDERR_FILENO); 886 } 887 888 ret = qemu_daemon(1, 0); 889 890 /* Temporarily redirect stderr to the parent's pipe... */ 891 dup2(stderr_fd[1], STDERR_FILENO); 892 if (ret < 0) { 893 error_report("Failed to daemonize: %s", strerror(errno)); 894 exit(EXIT_FAILURE); 895 } 896 897 /* ... close the descriptor we inherited and go on. */ 898 close(stderr_fd[1]); 899 } else { 900 bool errors = false; 901 char *buf; 902 903 /* In the parent. Print error messages from the child until 904 * it closes the pipe. 905 */ 906 close(stderr_fd[1]); 907 buf = g_malloc(1024); 908 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 909 errors = true; 910 ret = qemu_write_full(STDERR_FILENO, buf, ret); 911 if (ret < 0) { 912 exit(EXIT_FAILURE); 913 } 914 } 915 if (ret < 0) { 916 error_report("Cannot read from daemon: %s", 917 strerror(errno)); 918 exit(EXIT_FAILURE); 919 } 920 921 /* Usually the daemon should not print any message. 922 * Exit with zero status in that case. 923 */ 924 exit(errors); 925 } 926 #else /* WIN32 */ 927 error_report("Unable to fork into background on Windows hosts"); 928 exit(EXIT_FAILURE); 929 #endif /* WIN32 */ 930 } 931 932 if (device != NULL && sockpath == NULL) { 933 sockpath = g_malloc(128); 934 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 935 } 936 937 server = qio_net_listener_new(); 938 if (socket_activation == 0) { 939 int backlog; 940 941 if (persistent || shared == 0) { 942 backlog = SOMAXCONN; 943 } else { 944 backlog = MIN(shared, SOMAXCONN); 945 } 946 saddr = nbd_build_socket_address(sockpath, bindto, port); 947 if (qio_net_listener_open_sync(server, saddr, backlog, 948 &local_err) < 0) { 949 object_unref(OBJECT(server)); 950 error_report_err(local_err); 951 exit(EXIT_FAILURE); 952 } 953 } else { 954 size_t i; 955 /* See comment in check_socket_activation above. */ 956 for (i = 0; i < socket_activation; i++) { 957 QIOChannelSocket *sioc; 958 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 959 &local_err); 960 if (sioc == NULL) { 961 object_unref(OBJECT(server)); 962 error_reportf_err(local_err, 963 "Failed to use socket activation: "); 964 exit(EXIT_FAILURE); 965 } 966 qio_net_listener_add(server, sioc); 967 object_unref(OBJECT(sioc)); 968 } 969 } 970 971 if (qemu_init_main_loop(&local_err)) { 972 error_report_err(local_err); 973 exit(EXIT_FAILURE); 974 } 975 bdrv_init(); 976 atexit(qemu_nbd_shutdown); 977 978 srcpath = argv[optind]; 979 if (imageOpts) { 980 QemuOpts *opts; 981 if (fmt) { 982 error_report("--image-opts and -f are mutually exclusive"); 983 exit(EXIT_FAILURE); 984 } 985 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 986 if (!opts) { 987 qemu_opts_reset(&file_opts); 988 exit(EXIT_FAILURE); 989 } 990 options = qemu_opts_to_qdict(opts, NULL); 991 qemu_opts_reset(&file_opts); 992 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 993 } else { 994 if (fmt) { 995 options = qdict_new(); 996 qdict_put_str(options, "driver", fmt); 997 } 998 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 999 } 1000 1001 if (!blk) { 1002 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1003 argv[optind]); 1004 exit(EXIT_FAILURE); 1005 } 1006 bs = blk_bs(blk); 1007 1008 if (dev_offset) { 1009 QDict *raw_opts = qdict_new(); 1010 qdict_put_str(raw_opts, "driver", "raw"); 1011 qdict_put_str(raw_opts, "file", bs->node_name); 1012 qdict_put_int(raw_opts, "offset", dev_offset); 1013 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1014 blk_remove_bs(blk); 1015 blk_insert_bs(blk, bs, &error_fatal); 1016 bdrv_unref(bs); 1017 } 1018 1019 blk_set_enable_write_cache(blk, !writethrough); 1020 1021 if (sn_opts) { 1022 ret = bdrv_snapshot_load_tmp(bs, 1023 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1024 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1025 &local_err); 1026 } else if (sn_id_or_name) { 1027 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1028 &local_err); 1029 } 1030 if (ret < 0) { 1031 error_reportf_err(local_err, "Failed to load snapshot: "); 1032 exit(EXIT_FAILURE); 1033 } 1034 1035 bs->detect_zeroes = detect_zeroes; 1036 1037 nbd_server_is_qemu_nbd(true); 1038 1039 export_opts = g_new(BlockExportOptions, 1); 1040 *export_opts = (BlockExportOptions) { 1041 .type = BLOCK_EXPORT_TYPE_NBD, 1042 .id = g_strdup("qemu-nbd-export"), 1043 .node_name = g_strdup(bdrv_get_node_name(bs)), 1044 .has_writethrough = true, 1045 .writethrough = writethrough, 1046 .has_writable = true, 1047 .writable = !readonly, 1048 .u.nbd = { 1049 .has_name = true, 1050 .name = g_strdup(export_name), 1051 .has_description = !!export_description, 1052 .description = g_strdup(export_description), 1053 .has_bitmaps = !!bitmaps, 1054 .bitmaps = bitmaps, 1055 .has_allocation_depth = alloc_depth, 1056 .allocation_depth = alloc_depth, 1057 }, 1058 }; 1059 blk_exp_add(export_opts, &error_fatal); 1060 qapi_free_BlockExportOptions(export_opts); 1061 1062 if (device) { 1063 #if HAVE_NBD_DEVICE 1064 int ret; 1065 1066 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1067 if (ret != 0) { 1068 error_report("Failed to create client thread: %s", strerror(ret)); 1069 exit(EXIT_FAILURE); 1070 } 1071 #endif 1072 } else { 1073 /* Shut up GCC warnings. */ 1074 memset(&client_thread, 0, sizeof(client_thread)); 1075 } 1076 1077 nbd_update_server_watch(); 1078 1079 if (pid_file_name) { 1080 qemu_write_pidfile(pid_file_name, &error_fatal); 1081 } 1082 1083 /* now when the initialization is (almost) complete, chdir("/") 1084 * to free any busy filesystems */ 1085 if (chdir("/") < 0) { 1086 error_report("Could not chdir to root directory: %s", 1087 strerror(errno)); 1088 exit(EXIT_FAILURE); 1089 } 1090 1091 if (fork_process) { 1092 dup2(old_stderr, STDERR_FILENO); 1093 close(old_stderr); 1094 } 1095 1096 state = RUNNING; 1097 do { 1098 main_loop_wait(false); 1099 if (state == TERMINATE) { 1100 blk_exp_close_all(); 1101 state = TERMINATED; 1102 } 1103 } while (state != TERMINATED); 1104 1105 blk_unref(blk); 1106 if (sockpath) { 1107 unlink(sockpath); 1108 } 1109 1110 qemu_opts_del(sn_opts); 1111 1112 if (device) { 1113 void *ret; 1114 pthread_join(client_thread, &ret); 1115 exit(ret != NULL); 1116 } else { 1117 exit(EXIT_SUCCESS); 1118 } 1119 } 1120