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 "crypto/tlscreds.h" 47 #include "trace/control.h" 48 #include "qemu-version.h" 49 50 #ifdef __linux__ 51 #define HAVE_NBD_DEVICE 1 52 #else 53 #define HAVE_NBD_DEVICE 0 54 #endif 55 56 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 57 #define QEMU_NBD_OPT_CACHE 256 58 #define QEMU_NBD_OPT_AIO 257 59 #define QEMU_NBD_OPT_DISCARD 258 60 #define QEMU_NBD_OPT_DETECT_ZEROES 259 61 #define QEMU_NBD_OPT_OBJECT 260 62 #define QEMU_NBD_OPT_TLSCREDS 261 63 #define QEMU_NBD_OPT_IMAGE_OPTS 262 64 #define QEMU_NBD_OPT_FORK 263 65 #define QEMU_NBD_OPT_TLSAUTHZ 264 66 #define QEMU_NBD_OPT_PID_FILE 265 67 68 #define MBR_SIZE 512 69 70 static int verbose; 71 static char *srcpath; 72 static SocketAddress *saddr; 73 static int persistent = 0; 74 static enum { RUNNING, TERMINATE, TERMINATED } state; 75 static int shared = 1; 76 static int nb_fds; 77 static QIONetListener *server; 78 static QCryptoTLSCreds *tlscreds; 79 static const char *tlsauthz; 80 81 static void usage(const char *name) 82 { 83 (printf) ( 84 "Usage: %s [OPTIONS] FILE\n" 85 " or: %s -L [OPTIONS]\n" 86 "QEMU Disk Network Block Device Utility\n" 87 "\n" 88 " -h, --help display this help and exit\n" 89 " -V, --version output version information and exit\n" 90 "\n" 91 "Connection properties:\n" 92 " -p, --port=PORT port to listen on (default `%d')\n" 93 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 94 " -k, --socket=PATH path to the unix socket\n" 95 " (default '"SOCKET_PATH"')\n" 96 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 97 " -t, --persistent don't exit on the last connection\n" 98 " -v, --verbose display extra debugging information\n" 99 " -x, --export-name=NAME expose export by name (default is empty string)\n" 100 " -D, --description=TEXT export a human-readable description\n" 101 "\n" 102 "Exposing part of the image:\n" 103 " -o, --offset=OFFSET offset into the image\n" 104 " -A, --allocation-depth expose the allocation depth\n" 105 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 106 "\n" 107 "General purpose options:\n" 108 " -L, --list list exports available from another NBD server\n" 109 " --object type,id=ID,... define an object such as 'secret' for providing\n" 110 " passwords and/or encryption keys\n" 111 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 112 " --tls-authz=ID use id of an earlier --object to provide\n" 113 " authorization\n" 114 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 115 " specify tracing options\n" 116 " --fork fork off the server process and exit the parent\n" 117 " once the server is running\n" 118 " --pid-file=PATH store the server's process ID in the given file\n" 119 #if HAVE_NBD_DEVICE 120 "\n" 121 "Kernel NBD client support:\n" 122 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 123 " -d, --disconnect disconnect the specified device\n" 124 #endif 125 "\n" 126 "Block device options:\n" 127 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 128 " -r, --read-only export read-only\n" 129 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 130 " file with backing_file=FILE, redirect the write to\n" 131 " the temporary one\n" 132 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 133 " load an internal snapshot inside FILE and export it\n" 134 " as an read-only device, SNAPSHOT_PARAM format is\n" 135 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 136 " '[ID_OR_NAME]'\n" 137 " -n, --nocache disable host cache\n" 138 " --cache=MODE set cache mode (none, writeback, ...)\n" 139 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 140 " --discard=MODE set discard mode (ignore, unmap)\n" 141 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 142 " --image-opts treat FILE as a full set of image options\n" 143 "\n" 144 QEMU_HELP_BOTTOM "\n" 145 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 146 } 147 148 static void version(const char *name) 149 { 150 printf( 151 "%s " QEMU_FULL_VERSION "\n" 152 "Written by Anthony Liguori.\n" 153 "\n" 154 QEMU_COPYRIGHT "\n" 155 "This is free software; see the source for copying conditions. There is NO\n" 156 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 157 , name); 158 } 159 160 #ifdef CONFIG_POSIX 161 /* 162 * The client thread uses SIGTERM to interrupt the server. A signal 163 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 164 */ 165 void qemu_system_killed(int signum, pid_t pid) 166 { 167 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 168 qemu_notify_event(); 169 } 170 #endif /* CONFIG_POSIX */ 171 172 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 173 const char *hostname) 174 { 175 int ret = EXIT_FAILURE; 176 int rc; 177 Error *err = NULL; 178 QIOChannelSocket *sioc; 179 NBDExportInfo *list; 180 int i, j; 181 182 sioc = qio_channel_socket_new(); 183 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 184 error_report_err(err); 185 goto out; 186 } 187 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 188 &err); 189 if (rc < 0) { 190 if (err) { 191 error_report_err(err); 192 } 193 goto out; 194 } 195 printf("exports available: %d\n", rc); 196 for (i = 0; i < rc; i++) { 197 printf(" export: '%s'\n", list[i].name); 198 if (list[i].description && *list[i].description) { 199 printf(" description: %s\n", list[i].description); 200 } 201 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 202 static const char *const flag_names[] = { 203 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 204 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 205 [NBD_FLAG_SEND_FUA_BIT] = "fua", 206 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 207 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 208 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 209 [NBD_FLAG_SEND_DF_BIT] = "df", 210 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 211 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 212 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 213 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 214 }; 215 216 printf(" size: %" PRIu64 "\n", list[i].size); 217 printf(" flags: 0x%x (", list[i].flags); 218 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 219 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 220 printf(" %s", flag_names[bit]); 221 } 222 } 223 printf(" )\n"); 224 } 225 if (list[i].min_block) { 226 printf(" min block: %u\n", list[i].min_block); 227 printf(" opt block: %u\n", list[i].opt_block); 228 printf(" max block: %u\n", list[i].max_block); 229 } 230 if (list[i].n_contexts) { 231 printf(" available meta contexts: %d\n", list[i].n_contexts); 232 for (j = 0; j < list[i].n_contexts; j++) { 233 printf(" %s\n", list[i].contexts[j]); 234 } 235 } 236 } 237 nbd_free_export_list(list, rc); 238 239 ret = EXIT_SUCCESS; 240 out: 241 object_unref(OBJECT(sioc)); 242 return ret; 243 } 244 245 246 #if HAVE_NBD_DEVICE 247 static void *show_parts(void *arg) 248 { 249 char *device = arg; 250 int nbd; 251 252 /* linux just needs an open() to trigger 253 * the partition table update 254 * but remember to load the module with max_part != 0 : 255 * modprobe nbd max_part=63 256 */ 257 nbd = open(device, O_RDWR); 258 if (nbd >= 0) { 259 close(nbd); 260 } 261 return NULL; 262 } 263 264 static void *nbd_client_thread(void *arg) 265 { 266 char *device = arg; 267 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 268 QIOChannelSocket *sioc; 269 int fd = -1; 270 int ret = EXIT_FAILURE; 271 pthread_t show_parts_thread; 272 Error *local_error = NULL; 273 274 sioc = qio_channel_socket_new(); 275 if (qio_channel_socket_connect_sync(sioc, 276 saddr, 277 &local_error) < 0) { 278 error_report_err(local_error); 279 goto out; 280 } 281 282 if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 283 NULL, NULL, NULL, &info, &local_error) < 0) { 284 if (local_error) { 285 error_report_err(local_error); 286 } 287 goto out; 288 } 289 290 fd = open(device, O_RDWR); 291 if (fd < 0) { 292 /* Linux-only, we can use %m in printf. */ 293 error_report("Failed to open %s: %m", device); 294 goto out; 295 } 296 297 if (nbd_init(fd, sioc, &info, &local_error) < 0) { 298 error_report_err(local_error); 299 goto out; 300 } 301 302 /* update partition table */ 303 pthread_create(&show_parts_thread, NULL, show_parts, device); 304 305 if (verbose) { 306 fprintf(stderr, "NBD device %s is now connected to %s\n", 307 device, srcpath); 308 } else { 309 /* Close stderr so that the qemu-nbd process exits. */ 310 dup2(STDOUT_FILENO, STDERR_FILENO); 311 } 312 313 if (nbd_client(fd) < 0) { 314 goto out; 315 } 316 317 ret = EXIT_SUCCESS; 318 319 out: 320 if (fd >= 0) { 321 close(fd); 322 } 323 object_unref(OBJECT(sioc)); 324 g_free(info.name); 325 kill(getpid(), SIGTERM); 326 return (void *) (intptr_t) ret; 327 } 328 #endif /* HAVE_NBD_DEVICE */ 329 330 static int nbd_can_accept(void) 331 { 332 return state == RUNNING && (shared == 0 || nb_fds < shared); 333 } 334 335 static void nbd_update_server_watch(void); 336 337 static void nbd_client_closed(NBDClient *client, bool negotiated) 338 { 339 nb_fds--; 340 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 341 state = TERMINATE; 342 } 343 nbd_update_server_watch(); 344 nbd_client_put(client); 345 } 346 347 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 348 gpointer opaque) 349 { 350 if (state >= TERMINATE) { 351 return; 352 } 353 354 nb_fds++; 355 nbd_update_server_watch(); 356 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 357 } 358 359 static void nbd_update_server_watch(void) 360 { 361 if (nbd_can_accept()) { 362 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 363 } else { 364 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 365 } 366 } 367 368 369 static SocketAddress *nbd_build_socket_address(const char *sockpath, 370 const char *bindto, 371 const char *port) 372 { 373 SocketAddress *saddr; 374 375 saddr = g_new0(SocketAddress, 1); 376 if (sockpath) { 377 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 378 saddr->u.q_unix.path = g_strdup(sockpath); 379 } else { 380 InetSocketAddress *inet; 381 saddr->type = SOCKET_ADDRESS_TYPE_INET; 382 inet = &saddr->u.inet; 383 inet->host = g_strdup(bindto); 384 if (port) { 385 inet->port = g_strdup(port); 386 } else { 387 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 388 } 389 } 390 391 return saddr; 392 } 393 394 395 static QemuOptsList file_opts = { 396 .name = "file", 397 .implied_opt_name = "file", 398 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 399 .desc = { 400 /* no elements => accept any params */ 401 { /* end of list */ } 402 }, 403 }; 404 405 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 406 Error **errp) 407 { 408 Object *obj; 409 QCryptoTLSCreds *creds; 410 411 obj = object_resolve_path_component( 412 object_get_objects_root(), id); 413 if (!obj) { 414 error_setg(errp, "No TLS credentials with id '%s'", 415 id); 416 return NULL; 417 } 418 creds = (QCryptoTLSCreds *) 419 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 420 if (!creds) { 421 error_setg(errp, "Object with id '%s' is not TLS credentials", 422 id); 423 return NULL; 424 } 425 426 if (!qcrypto_tls_creds_check_endpoint(creds, 427 list 428 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT 429 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, 430 errp)) { 431 return NULL; 432 } 433 object_ref(obj); 434 return creds; 435 } 436 437 static void setup_address_and_port(const char **address, const char **port) 438 { 439 if (*address == NULL) { 440 *address = "0.0.0.0"; 441 } 442 443 if (*port == NULL) { 444 *port = stringify(NBD_DEFAULT_PORT); 445 } 446 } 447 448 /* 449 * Check socket parameters compatibility when socket activation is used. 450 */ 451 static const char *socket_activation_validate_opts(const char *device, 452 const char *sockpath, 453 const char *address, 454 const char *port, 455 bool list) 456 { 457 if (device != NULL) { 458 return "NBD device can't be set when using socket activation"; 459 } 460 461 if (sockpath != NULL) { 462 return "Unix socket can't be set when using socket activation"; 463 } 464 465 if (address != NULL) { 466 return "The interface can't be set when using socket activation"; 467 } 468 469 if (port != NULL) { 470 return "TCP port number can't be set when using socket activation"; 471 } 472 473 if (list) { 474 return "List mode is incompatible with socket activation"; 475 } 476 477 return NULL; 478 } 479 480 static void qemu_nbd_shutdown(void) 481 { 482 job_cancel_sync_all(); 483 blk_exp_close_all(); 484 bdrv_close_all(); 485 } 486 487 int main(int argc, char **argv) 488 { 489 BlockBackend *blk; 490 BlockDriverState *bs; 491 uint64_t dev_offset = 0; 492 bool readonly = false; 493 bool disconnect = false; 494 const char *bindto = NULL; 495 const char *port = NULL; 496 char *sockpath = NULL; 497 char *device = NULL; 498 QemuOpts *sn_opts = NULL; 499 const char *sn_id_or_name = NULL; 500 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 501 struct option lopt[] = { 502 { "help", no_argument, NULL, 'h' }, 503 { "version", no_argument, NULL, 'V' }, 504 { "bind", required_argument, NULL, 'b' }, 505 { "port", required_argument, NULL, 'p' }, 506 { "socket", required_argument, NULL, 'k' }, 507 { "offset", required_argument, NULL, 'o' }, 508 { "read-only", no_argument, NULL, 'r' }, 509 { "allocation-depth", no_argument, NULL, 'A' }, 510 { "bitmap", required_argument, NULL, 'B' }, 511 { "connect", required_argument, NULL, 'c' }, 512 { "disconnect", no_argument, NULL, 'd' }, 513 { "list", no_argument, NULL, 'L' }, 514 { "snapshot", no_argument, NULL, 's' }, 515 { "load-snapshot", required_argument, NULL, 'l' }, 516 { "nocache", no_argument, NULL, 'n' }, 517 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 518 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 519 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 520 { "detect-zeroes", required_argument, NULL, 521 QEMU_NBD_OPT_DETECT_ZEROES }, 522 { "shared", required_argument, NULL, 'e' }, 523 { "format", required_argument, NULL, 'f' }, 524 { "persistent", no_argument, NULL, 't' }, 525 { "verbose", no_argument, NULL, 'v' }, 526 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 527 { "export-name", required_argument, NULL, 'x' }, 528 { "description", required_argument, NULL, 'D' }, 529 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 530 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 531 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 532 { "trace", required_argument, NULL, 'T' }, 533 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 534 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 535 { NULL, 0, NULL, 0 } 536 }; 537 int ch; 538 int opt_ind = 0; 539 int flags = BDRV_O_RDWR; 540 int ret = 0; 541 bool seen_cache = false; 542 bool seen_discard = false; 543 bool seen_aio = false; 544 pthread_t client_thread; 545 const char *fmt = NULL; 546 Error *local_err = NULL; 547 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 548 QDict *options = NULL; 549 const char *export_name = NULL; /* defaults to "" later for server mode */ 550 const char *export_description = NULL; 551 strList *bitmaps = NULL; 552 bool alloc_depth = false; 553 const char *tlscredsid = NULL; 554 bool imageOpts = false; 555 bool writethrough = true; 556 bool fork_process = false; 557 bool list = false; 558 int old_stderr = -1; 559 unsigned socket_activation; 560 const char *pid_file_name = NULL; 561 BlockExportOptions *export_opts; 562 563 #ifdef CONFIG_POSIX 564 os_setup_early_signal_handling(); 565 os_setup_signal_handling(); 566 #endif 567 568 socket_init(); 569 error_init(argv[0]); 570 module_call_init(MODULE_INIT_TRACE); 571 qcrypto_init(&error_fatal); 572 573 module_call_init(MODULE_INIT_QOM); 574 qemu_add_opts(&qemu_trace_opts); 575 qemu_init_exec_dir(argv[0]); 576 577 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 578 switch (ch) { 579 case 's': 580 flags |= BDRV_O_SNAPSHOT; 581 break; 582 case 'n': 583 optarg = (char *) "none"; 584 /* fallthrough */ 585 case QEMU_NBD_OPT_CACHE: 586 if (seen_cache) { 587 error_report("-n and --cache can only be specified once"); 588 exit(EXIT_FAILURE); 589 } 590 seen_cache = true; 591 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 592 error_report("Invalid cache mode `%s'", optarg); 593 exit(EXIT_FAILURE); 594 } 595 break; 596 case QEMU_NBD_OPT_AIO: 597 if (seen_aio) { 598 error_report("--aio can only be specified once"); 599 exit(EXIT_FAILURE); 600 } 601 seen_aio = true; 602 if (bdrv_parse_aio(optarg, &flags) < 0) { 603 error_report("Invalid aio mode '%s'", optarg); 604 exit(EXIT_FAILURE); 605 } 606 break; 607 case QEMU_NBD_OPT_DISCARD: 608 if (seen_discard) { 609 error_report("--discard can only be specified once"); 610 exit(EXIT_FAILURE); 611 } 612 seen_discard = true; 613 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 614 error_report("Invalid discard mode `%s'", optarg); 615 exit(EXIT_FAILURE); 616 } 617 break; 618 case QEMU_NBD_OPT_DETECT_ZEROES: 619 detect_zeroes = 620 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 621 optarg, 622 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 623 &local_err); 624 if (local_err) { 625 error_reportf_err(local_err, 626 "Failed to parse detect_zeroes mode: "); 627 exit(EXIT_FAILURE); 628 } 629 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 630 !(flags & BDRV_O_UNMAP)) { 631 error_report("setting detect-zeroes to unmap is not allowed " 632 "without setting discard operation to unmap"); 633 exit(EXIT_FAILURE); 634 } 635 break; 636 case 'b': 637 bindto = optarg; 638 break; 639 case 'p': 640 port = optarg; 641 break; 642 case 'o': 643 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 644 error_report("Invalid offset '%s'", optarg); 645 exit(EXIT_FAILURE); 646 } 647 break; 648 case 'l': 649 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 650 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 651 optarg, false); 652 if (!sn_opts) { 653 error_report("Failed in parsing snapshot param `%s'", 654 optarg); 655 exit(EXIT_FAILURE); 656 } 657 } else { 658 sn_id_or_name = optarg; 659 } 660 /* fall through */ 661 case 'r': 662 readonly = true; 663 flags &= ~BDRV_O_RDWR; 664 break; 665 case 'A': 666 alloc_depth = true; 667 break; 668 case 'B': 669 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg)); 670 break; 671 case 'k': 672 sockpath = optarg; 673 if (sockpath[0] != '/') { 674 error_report("socket path must be absolute"); 675 exit(EXIT_FAILURE); 676 } 677 break; 678 case 'd': 679 disconnect = true; 680 break; 681 case 'c': 682 device = optarg; 683 break; 684 case 'e': 685 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 686 shared < 0) { 687 error_report("Invalid shared device number '%s'", optarg); 688 exit(EXIT_FAILURE); 689 } 690 break; 691 case 'f': 692 fmt = optarg; 693 break; 694 case 't': 695 persistent = 1; 696 break; 697 case 'x': 698 export_name = optarg; 699 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 700 error_report("export name '%s' too long", export_name); 701 exit(EXIT_FAILURE); 702 } 703 break; 704 case 'D': 705 export_description = optarg; 706 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 707 error_report("export description '%s' too long", 708 export_description); 709 exit(EXIT_FAILURE); 710 } 711 break; 712 case 'v': 713 verbose = 1; 714 break; 715 case 'V': 716 version(argv[0]); 717 exit(0); 718 break; 719 case 'h': 720 usage(argv[0]); 721 exit(0); 722 break; 723 case '?': 724 error_report("Try `%s --help' for more information.", argv[0]); 725 exit(EXIT_FAILURE); 726 case QEMU_NBD_OPT_OBJECT: 727 user_creatable_process_cmdline(optarg); 728 break; 729 case QEMU_NBD_OPT_TLSCREDS: 730 tlscredsid = optarg; 731 break; 732 case QEMU_NBD_OPT_IMAGE_OPTS: 733 imageOpts = true; 734 break; 735 case 'T': 736 trace_opt_parse(optarg); 737 break; 738 case QEMU_NBD_OPT_TLSAUTHZ: 739 tlsauthz = optarg; 740 break; 741 case QEMU_NBD_OPT_FORK: 742 fork_process = true; 743 break; 744 case 'L': 745 list = true; 746 break; 747 case QEMU_NBD_OPT_PID_FILE: 748 pid_file_name = optarg; 749 break; 750 } 751 } 752 753 if (list) { 754 if (argc != optind) { 755 error_report("List mode is incompatible with a file name"); 756 exit(EXIT_FAILURE); 757 } 758 if (export_name || export_description || dev_offset || 759 device || disconnect || fmt || sn_id_or_name || bitmaps || 760 alloc_depth || seen_aio || seen_discard || seen_cache) { 761 error_report("List mode is incompatible with per-device settings"); 762 exit(EXIT_FAILURE); 763 } 764 if (fork_process) { 765 error_report("List mode is incompatible with forking"); 766 exit(EXIT_FAILURE); 767 } 768 } else if ((argc - optind) != 1) { 769 error_report("Invalid number of arguments"); 770 error_printf("Try `%s --help' for more information.\n", argv[0]); 771 exit(EXIT_FAILURE); 772 } else if (!export_name) { 773 export_name = ""; 774 } 775 776 if (!trace_init_backends()) { 777 exit(1); 778 } 779 trace_init_file(); 780 qemu_set_log(LOG_TRACE); 781 782 socket_activation = check_socket_activation(); 783 if (socket_activation == 0) { 784 setup_address_and_port(&bindto, &port); 785 } else { 786 /* Using socket activation - check user didn't use -p etc. */ 787 const char *err_msg = socket_activation_validate_opts(device, sockpath, 788 bindto, port, 789 list); 790 if (err_msg != NULL) { 791 error_report("%s", err_msg); 792 exit(EXIT_FAILURE); 793 } 794 795 /* qemu-nbd can only listen on a single socket. */ 796 if (socket_activation > 1) { 797 error_report("qemu-nbd does not support socket activation with %s > 1", 798 "LISTEN_FDS"); 799 exit(EXIT_FAILURE); 800 } 801 } 802 803 if (tlscredsid) { 804 if (sockpath) { 805 error_report("TLS is only supported with IPv4/IPv6"); 806 exit(EXIT_FAILURE); 807 } 808 if (device) { 809 error_report("TLS is not supported with a host device"); 810 exit(EXIT_FAILURE); 811 } 812 if (tlsauthz && list) { 813 error_report("TLS authorization is incompatible with export list"); 814 exit(EXIT_FAILURE); 815 } 816 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 817 if (local_err) { 818 error_reportf_err(local_err, "Failed to get TLS creds: "); 819 exit(EXIT_FAILURE); 820 } 821 } else { 822 if (tlsauthz) { 823 error_report("--tls-authz is not permitted without --tls-creds"); 824 exit(EXIT_FAILURE); 825 } 826 } 827 828 if (list) { 829 saddr = nbd_build_socket_address(sockpath, bindto, port); 830 return qemu_nbd_client_list(saddr, tlscreds, bindto); 831 } 832 833 #if !HAVE_NBD_DEVICE 834 if (disconnect || device) { 835 error_report("Kernel /dev/nbdN support not available"); 836 exit(EXIT_FAILURE); 837 } 838 #else /* HAVE_NBD_DEVICE */ 839 if (disconnect) { 840 int nbdfd = open(argv[optind], O_RDWR); 841 if (nbdfd < 0) { 842 error_report("Cannot open %s: %s", argv[optind], 843 strerror(errno)); 844 exit(EXIT_FAILURE); 845 } 846 nbd_disconnect(nbdfd); 847 848 close(nbdfd); 849 850 printf("%s disconnected\n", argv[optind]); 851 852 return 0; 853 } 854 #endif 855 856 if ((device && !verbose) || fork_process) { 857 #ifndef WIN32 858 int stderr_fd[2]; 859 pid_t pid; 860 int ret; 861 862 if (qemu_pipe(stderr_fd) < 0) { 863 error_report("Error setting up communication pipe: %s", 864 strerror(errno)); 865 exit(EXIT_FAILURE); 866 } 867 868 /* Now daemonize, but keep a communication channel open to 869 * print errors and exit with the proper status code. 870 */ 871 pid = fork(); 872 if (pid < 0) { 873 error_report("Failed to fork: %s", strerror(errno)); 874 exit(EXIT_FAILURE); 875 } else if (pid == 0) { 876 close(stderr_fd[0]); 877 878 /* Remember parent's stderr if we will be restoring it. */ 879 if (fork_process) { 880 old_stderr = dup(STDERR_FILENO); 881 } 882 883 ret = qemu_daemon(1, 0); 884 885 /* Temporarily redirect stderr to the parent's pipe... */ 886 dup2(stderr_fd[1], STDERR_FILENO); 887 if (ret < 0) { 888 error_report("Failed to daemonize: %s", strerror(errno)); 889 exit(EXIT_FAILURE); 890 } 891 892 /* ... close the descriptor we inherited and go on. */ 893 close(stderr_fd[1]); 894 } else { 895 bool errors = false; 896 char *buf; 897 898 /* In the parent. Print error messages from the child until 899 * it closes the pipe. 900 */ 901 close(stderr_fd[1]); 902 buf = g_malloc(1024); 903 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 904 errors = true; 905 ret = qemu_write_full(STDERR_FILENO, buf, ret); 906 if (ret < 0) { 907 exit(EXIT_FAILURE); 908 } 909 } 910 if (ret < 0) { 911 error_report("Cannot read from daemon: %s", 912 strerror(errno)); 913 exit(EXIT_FAILURE); 914 } 915 916 /* Usually the daemon should not print any message. 917 * Exit with zero status in that case. 918 */ 919 exit(errors); 920 } 921 #else /* WIN32 */ 922 error_report("Unable to fork into background on Windows hosts"); 923 exit(EXIT_FAILURE); 924 #endif /* WIN32 */ 925 } 926 927 if (device != NULL && sockpath == NULL) { 928 sockpath = g_malloc(128); 929 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 930 } 931 932 server = qio_net_listener_new(); 933 if (socket_activation == 0) { 934 int backlog; 935 936 if (persistent || shared == 0) { 937 backlog = SOMAXCONN; 938 } else { 939 backlog = MIN(shared, SOMAXCONN); 940 } 941 saddr = nbd_build_socket_address(sockpath, bindto, port); 942 if (qio_net_listener_open_sync(server, saddr, backlog, 943 &local_err) < 0) { 944 object_unref(OBJECT(server)); 945 error_report_err(local_err); 946 exit(EXIT_FAILURE); 947 } 948 } else { 949 size_t i; 950 /* See comment in check_socket_activation above. */ 951 for (i = 0; i < socket_activation; i++) { 952 QIOChannelSocket *sioc; 953 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 954 &local_err); 955 if (sioc == NULL) { 956 object_unref(OBJECT(server)); 957 error_reportf_err(local_err, 958 "Failed to use socket activation: "); 959 exit(EXIT_FAILURE); 960 } 961 qio_net_listener_add(server, sioc); 962 object_unref(OBJECT(sioc)); 963 } 964 } 965 966 qemu_init_main_loop(&error_fatal); 967 bdrv_init(); 968 atexit(qemu_nbd_shutdown); 969 970 srcpath = argv[optind]; 971 if (imageOpts) { 972 QemuOpts *opts; 973 if (fmt) { 974 error_report("--image-opts and -f are mutually exclusive"); 975 exit(EXIT_FAILURE); 976 } 977 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 978 if (!opts) { 979 qemu_opts_reset(&file_opts); 980 exit(EXIT_FAILURE); 981 } 982 options = qemu_opts_to_qdict(opts, NULL); 983 qemu_opts_reset(&file_opts); 984 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 985 } else { 986 if (fmt) { 987 options = qdict_new(); 988 qdict_put_str(options, "driver", fmt); 989 } 990 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 991 } 992 993 if (!blk) { 994 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 995 argv[optind]); 996 exit(EXIT_FAILURE); 997 } 998 bs = blk_bs(blk); 999 1000 if (dev_offset) { 1001 QDict *raw_opts = qdict_new(); 1002 qdict_put_str(raw_opts, "driver", "raw"); 1003 qdict_put_str(raw_opts, "file", bs->node_name); 1004 qdict_put_int(raw_opts, "offset", dev_offset); 1005 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1006 blk_remove_bs(blk); 1007 blk_insert_bs(blk, bs, &error_fatal); 1008 bdrv_unref(bs); 1009 } 1010 1011 blk_set_enable_write_cache(blk, !writethrough); 1012 1013 if (sn_opts) { 1014 ret = bdrv_snapshot_load_tmp(bs, 1015 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1016 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1017 &local_err); 1018 } else if (sn_id_or_name) { 1019 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1020 &local_err); 1021 } 1022 if (ret < 0) { 1023 error_reportf_err(local_err, "Failed to load snapshot: "); 1024 exit(EXIT_FAILURE); 1025 } 1026 1027 bs->detect_zeroes = detect_zeroes; 1028 1029 nbd_server_is_qemu_nbd(true); 1030 1031 export_opts = g_new(BlockExportOptions, 1); 1032 *export_opts = (BlockExportOptions) { 1033 .type = BLOCK_EXPORT_TYPE_NBD, 1034 .id = g_strdup("qemu-nbd-export"), 1035 .node_name = g_strdup(bdrv_get_node_name(bs)), 1036 .has_writethrough = true, 1037 .writethrough = writethrough, 1038 .has_writable = true, 1039 .writable = !readonly, 1040 .u.nbd = { 1041 .has_name = true, 1042 .name = g_strdup(export_name), 1043 .has_description = !!export_description, 1044 .description = g_strdup(export_description), 1045 .has_bitmaps = !!bitmaps, 1046 .bitmaps = bitmaps, 1047 .has_allocation_depth = alloc_depth, 1048 .allocation_depth = alloc_depth, 1049 }, 1050 }; 1051 blk_exp_add(export_opts, &error_fatal); 1052 qapi_free_BlockExportOptions(export_opts); 1053 1054 if (device) { 1055 #if HAVE_NBD_DEVICE 1056 int ret; 1057 1058 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1059 if (ret != 0) { 1060 error_report("Failed to create client thread: %s", strerror(ret)); 1061 exit(EXIT_FAILURE); 1062 } 1063 #endif 1064 } else { 1065 /* Shut up GCC warnings. */ 1066 memset(&client_thread, 0, sizeof(client_thread)); 1067 } 1068 1069 nbd_update_server_watch(); 1070 1071 if (pid_file_name) { 1072 qemu_write_pidfile(pid_file_name, &error_fatal); 1073 } 1074 1075 /* now when the initialization is (almost) complete, chdir("/") 1076 * to free any busy filesystems */ 1077 if (chdir("/") < 0) { 1078 error_report("Could not chdir to root directory: %s", 1079 strerror(errno)); 1080 exit(EXIT_FAILURE); 1081 } 1082 1083 if (fork_process) { 1084 dup2(old_stderr, STDERR_FILENO); 1085 close(old_stderr); 1086 } 1087 1088 state = RUNNING; 1089 do { 1090 main_loop_wait(false); 1091 if (state == TERMINATE) { 1092 blk_exp_close_all(); 1093 state = TERMINATED; 1094 } 1095 } while (state != TERMINATED); 1096 1097 blk_unref(blk); 1098 if (sockpath) { 1099 unlink(sockpath); 1100 } 1101 1102 qemu_opts_del(sn_opts); 1103 1104 if (device) { 1105 void *ret; 1106 pthread_join(client_thread, &ret); 1107 exit(ret != NULL); 1108 } else { 1109 exit(EXIT_SUCCESS); 1110 } 1111 } 1112