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/help-texts.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 CONFIG_SELINUX 51 #include <selinux/selinux.h> 52 #endif 53 54 #ifdef __linux__ 55 #define HAVE_NBD_DEVICE 1 56 #else 57 #define HAVE_NBD_DEVICE 0 58 #endif 59 60 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 61 #define QEMU_NBD_OPT_CACHE 256 62 #define QEMU_NBD_OPT_AIO 257 63 #define QEMU_NBD_OPT_DISCARD 258 64 #define QEMU_NBD_OPT_DETECT_ZEROES 259 65 #define QEMU_NBD_OPT_OBJECT 260 66 #define QEMU_NBD_OPT_TLSCREDS 261 67 #define QEMU_NBD_OPT_IMAGE_OPTS 262 68 #define QEMU_NBD_OPT_FORK 263 69 #define QEMU_NBD_OPT_TLSAUTHZ 264 70 #define QEMU_NBD_OPT_PID_FILE 265 71 #define QEMU_NBD_OPT_SELINUX_LABEL 266 72 #define QEMU_NBD_OPT_TLSHOSTNAME 267 73 74 #define MBR_SIZE 512 75 76 static int persistent = 0; 77 static enum { RUNNING, TERMINATE, TERMINATED } state; 78 static int shared = 1; 79 static int nb_fds; 80 static QIONetListener *server; 81 static QCryptoTLSCreds *tlscreds; 82 static const char *tlsauthz; 83 84 static void usage(const char *name) 85 { 86 (printf) ( 87 "Usage: %s [OPTIONS] FILE\n" 88 " or: %s -L [OPTIONS]\n" 89 "QEMU Disk Network Block Device Utility\n" 90 "\n" 91 " -h, --help display this help and exit\n" 92 " -V, --version output version information and exit\n" 93 "\n" 94 "Connection properties:\n" 95 " -p, --port=PORT port to listen on (default `%d')\n" 96 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 97 " -k, --socket=PATH path to the unix socket\n" 98 " (default '"SOCKET_PATH"')\n" 99 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 100 " -t, --persistent don't exit on the last connection\n" 101 " -v, --verbose display extra debugging information\n" 102 " -x, --export-name=NAME expose export by name (default is empty string)\n" 103 " -D, --description=TEXT export a human-readable description\n" 104 "\n" 105 "Exposing part of the image:\n" 106 " -o, --offset=OFFSET offset into the image\n" 107 " -A, --allocation-depth expose the allocation depth\n" 108 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 109 "\n" 110 "General purpose options:\n" 111 " -L, --list list exports available from another NBD server\n" 112 " --object type,id=ID,... define an object such as 'secret' for providing\n" 113 " passwords and/or encryption keys\n" 114 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 115 " --tls-authz=ID use id of an earlier --object to provide\n" 116 " authorization\n" 117 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 118 " specify tracing options\n" 119 " --fork fork off the server process and exit the parent\n" 120 " once the server is running\n" 121 " --pid-file=PATH store the server's process ID in the given file\n" 122 #ifdef CONFIG_SELINUX 123 " --selinux-label=LABEL set SELinux process label on listening socket\n" 124 #endif 125 #if HAVE_NBD_DEVICE 126 "\n" 127 "Kernel NBD client support:\n" 128 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 129 " -d, --disconnect disconnect the specified device\n" 130 #endif 131 "\n" 132 "Block device options:\n" 133 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 134 " -r, --read-only export read-only\n" 135 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 136 " file with backing_file=FILE, redirect the write to\n" 137 " the temporary one\n" 138 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 139 " load an internal snapshot inside FILE and export it\n" 140 " as an read-only device, SNAPSHOT_PARAM format is\n" 141 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 142 " '[ID_OR_NAME]'\n" 143 " -n, --nocache disable host cache\n" 144 " --cache=MODE set cache mode used to access the disk image, the\n" 145 " valid options are: 'none', 'writeback' (default),\n" 146 " 'writethrough', 'directsync' and 'unsafe'\n" 147 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 148 " --discard=MODE set discard mode (ignore, unmap)\n" 149 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 150 " --image-opts treat FILE as a full set of image options\n" 151 "\n" 152 QEMU_HELP_BOTTOM "\n" 153 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 154 } 155 156 static void version(const char *name) 157 { 158 printf( 159 "%s " QEMU_FULL_VERSION "\n" 160 "Written by Anthony Liguori.\n" 161 "\n" 162 QEMU_COPYRIGHT "\n" 163 "This is free software; see the source for copying conditions. There is NO\n" 164 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 165 , name); 166 } 167 168 #ifdef CONFIG_POSIX 169 /* 170 * The client thread uses SIGTERM to interrupt the server. A signal 171 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 172 */ 173 void qemu_system_killed(int signum, pid_t pid) 174 { 175 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 176 qemu_notify_event(); 177 } 178 #endif /* CONFIG_POSIX */ 179 180 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 181 const char *hostname) 182 { 183 int ret = EXIT_FAILURE; 184 int rc; 185 Error *err = NULL; 186 QIOChannelSocket *sioc; 187 NBDExportInfo *list; 188 int i, j; 189 190 sioc = qio_channel_socket_new(); 191 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 192 error_report_err(err); 193 goto out; 194 } 195 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 196 &err); 197 if (rc < 0) { 198 if (err) { 199 error_report_err(err); 200 } 201 goto out; 202 } 203 printf("exports available: %d\n", rc); 204 for (i = 0; i < rc; i++) { 205 printf(" export: '%s'\n", list[i].name); 206 if (list[i].description && *list[i].description) { 207 printf(" description: %s\n", list[i].description); 208 } 209 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 210 static const char *const flag_names[] = { 211 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 212 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 213 [NBD_FLAG_SEND_FUA_BIT] = "fua", 214 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 215 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 216 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 217 [NBD_FLAG_SEND_DF_BIT] = "df", 218 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 219 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 220 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 221 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 222 }; 223 224 printf(" size: %" PRIu64 "\n", list[i].size); 225 printf(" flags: 0x%x (", list[i].flags); 226 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 227 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 228 printf(" %s", flag_names[bit]); 229 } 230 } 231 printf(" )\n"); 232 } 233 if (list[i].min_block) { 234 printf(" min block: %u\n", list[i].min_block); 235 printf(" opt block: %u\n", list[i].opt_block); 236 printf(" max block: %u\n", list[i].max_block); 237 } 238 printf(" transaction size: %s\n", 239 list[i].mode >= NBD_MODE_EXTENDED ? 240 "64-bit" : "32-bit"); 241 if (list[i].n_contexts) { 242 printf(" available meta contexts: %d\n", list[i].n_contexts); 243 for (j = 0; j < list[i].n_contexts; j++) { 244 printf(" %s\n", list[i].contexts[j]); 245 } 246 } 247 } 248 nbd_free_export_list(list, rc); 249 250 ret = EXIT_SUCCESS; 251 out: 252 object_unref(OBJECT(sioc)); 253 return ret; 254 } 255 256 257 struct NbdClientOpts { 258 char *device; 259 char *srcpath; 260 SocketAddress *saddr; 261 int old_stderr; 262 bool fork_process; 263 bool verbose; 264 }; 265 266 static void nbd_client_release_pipe(int old_stderr) 267 { 268 /* Close stderr so that the qemu-nbd process exits. */ 269 if (dup2(old_stderr, STDERR_FILENO) < 0) { 270 error_report("Could not release pipe to parent: %s", 271 strerror(errno)); 272 exit(EXIT_FAILURE); 273 } 274 if (old_stderr != STDOUT_FILENO && close(old_stderr) < 0) { 275 error_report("Could not release qemu-nbd: %s", strerror(errno)); 276 exit(EXIT_FAILURE); 277 } 278 } 279 280 #if HAVE_NBD_DEVICE 281 static void *show_parts(void *arg) 282 { 283 char *device = arg; 284 int nbd; 285 286 /* linux just needs an open() to trigger 287 * the partition table update 288 * but remember to load the module with max_part != 0 : 289 * modprobe nbd max_part=63 290 */ 291 nbd = open(device, O_RDWR); 292 if (nbd >= 0) { 293 close(nbd); 294 } 295 return NULL; 296 } 297 298 static void *nbd_client_thread(void *arg) 299 { 300 struct NbdClientOpts *opts = arg; 301 /* TODO: Revisit this if nbd.ko ever gains support for structured reply */ 302 NBDExportInfo info = { .request_sizes = false, .name = g_strdup(""), 303 .mode = NBD_MODE_SIMPLE }; 304 QIOChannelSocket *sioc; 305 int fd = -1; 306 int ret = EXIT_FAILURE; 307 pthread_t show_parts_thread; 308 Error *local_error = NULL; 309 310 sioc = qio_channel_socket_new(); 311 if (qio_channel_socket_connect_sync(sioc, 312 opts->saddr, 313 &local_error) < 0) { 314 error_report_err(local_error); 315 goto out; 316 } 317 318 if (nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, NULL, NULL, 319 &info, &local_error) < 0) { 320 if (local_error) { 321 error_report_err(local_error); 322 } 323 goto out; 324 } 325 326 fd = open(opts->device, O_RDWR); 327 if (fd < 0) { 328 /* Linux-only, we can use %m in printf. */ 329 error_report("Failed to open %s: %m", opts->device); 330 goto out; 331 } 332 333 if (nbd_init(fd, sioc, &info, &local_error) < 0) { 334 error_report_err(local_error); 335 goto out; 336 } 337 338 /* update partition table */ 339 pthread_create(&show_parts_thread, NULL, show_parts, opts->device); 340 341 if (opts->verbose && !opts->fork_process) { 342 fprintf(stderr, "NBD device %s is now connected to %s\n", 343 opts->device, opts->srcpath); 344 } else { 345 nbd_client_release_pipe(opts->old_stderr); 346 } 347 348 if (nbd_client(fd) < 0) { 349 goto out; 350 } 351 352 ret = EXIT_SUCCESS; 353 354 out: 355 if (fd >= 0) { 356 close(fd); 357 } 358 object_unref(OBJECT(sioc)); 359 g_free(info.name); 360 kill(getpid(), SIGTERM); 361 return (void *) (intptr_t) ret; 362 } 363 #endif /* HAVE_NBD_DEVICE */ 364 365 static int nbd_can_accept(void) 366 { 367 return state == RUNNING && (shared == 0 || nb_fds < shared); 368 } 369 370 static void nbd_update_server_watch(void); 371 372 static void nbd_client_closed(NBDClient *client, bool negotiated) 373 { 374 nb_fds--; 375 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 376 state = TERMINATE; 377 } 378 nbd_update_server_watch(); 379 nbd_client_put(client); 380 } 381 382 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 383 gpointer opaque) 384 { 385 if (state >= TERMINATE) { 386 return; 387 } 388 389 nb_fds++; 390 nbd_update_server_watch(); 391 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 392 } 393 394 static void nbd_update_server_watch(void) 395 { 396 if (nbd_can_accept()) { 397 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 398 } else { 399 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 400 } 401 } 402 403 404 static SocketAddress *nbd_build_socket_address(const char *sockpath, 405 const char *bindto, 406 const char *port) 407 { 408 SocketAddress *saddr; 409 410 saddr = g_new0(SocketAddress, 1); 411 if (sockpath) { 412 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 413 saddr->u.q_unix.path = g_strdup(sockpath); 414 } else { 415 InetSocketAddress *inet; 416 saddr->type = SOCKET_ADDRESS_TYPE_INET; 417 inet = &saddr->u.inet; 418 inet->host = g_strdup(bindto); 419 if (port) { 420 inet->port = g_strdup(port); 421 } else { 422 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 423 } 424 } 425 426 return saddr; 427 } 428 429 430 static QemuOptsList file_opts = { 431 .name = "file", 432 .implied_opt_name = "file", 433 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 434 .desc = { 435 /* no elements => accept any params */ 436 { /* end of list */ } 437 }, 438 }; 439 440 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 441 Error **errp) 442 { 443 Object *obj; 444 QCryptoTLSCreds *creds; 445 446 obj = object_resolve_path_component( 447 object_get_objects_root(), id); 448 if (!obj) { 449 error_setg(errp, "No TLS credentials with id '%s'", 450 id); 451 return NULL; 452 } 453 creds = (QCryptoTLSCreds *) 454 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 455 if (!creds) { 456 error_setg(errp, "Object with id '%s' is not TLS credentials", 457 id); 458 return NULL; 459 } 460 461 if (!qcrypto_tls_creds_check_endpoint(creds, 462 list 463 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT 464 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, 465 errp)) { 466 return NULL; 467 } 468 object_ref(obj); 469 return creds; 470 } 471 472 static void setup_address_and_port(const char **address, const char **port) 473 { 474 if (*address == NULL) { 475 *address = "0.0.0.0"; 476 } 477 478 if (*port == NULL) { 479 *port = stringify(NBD_DEFAULT_PORT); 480 } 481 } 482 483 /* 484 * Check socket parameters compatibility when socket activation is used. 485 */ 486 static const char *socket_activation_validate_opts(const char *device, 487 const char *sockpath, 488 const char *address, 489 const char *port, 490 const char *selinux, 491 bool list) 492 { 493 if (device != NULL) { 494 return "NBD device can't be set when using socket activation"; 495 } 496 497 if (sockpath != NULL) { 498 return "Unix socket can't be set when using socket activation"; 499 } 500 501 if (address != NULL) { 502 return "The interface can't be set when using socket activation"; 503 } 504 505 if (port != NULL) { 506 return "TCP port number can't be set when using socket activation"; 507 } 508 509 if (selinux != NULL) { 510 return "SELinux label can't be set when using socket activation"; 511 } 512 513 if (list) { 514 return "List mode is incompatible with socket activation"; 515 } 516 517 return NULL; 518 } 519 520 static void qemu_nbd_shutdown(void) 521 { 522 job_cancel_sync_all(); 523 blk_exp_close_all(); 524 bdrv_close_all(); 525 } 526 527 int main(int argc, char **argv) 528 { 529 BlockBackend *blk; 530 BlockDriverState *bs; 531 uint64_t dev_offset = 0; 532 bool readonly = false; 533 bool disconnect = false; 534 const char *bindto = NULL; 535 const char *port = NULL; 536 char *sockpath = NULL; 537 QemuOpts *sn_opts = NULL; 538 const char *sn_id_or_name = NULL; 539 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 540 struct option lopt[] = { 541 { "help", no_argument, NULL, 'h' }, 542 { "version", no_argument, NULL, 'V' }, 543 { "bind", required_argument, NULL, 'b' }, 544 { "port", required_argument, NULL, 'p' }, 545 { "socket", required_argument, NULL, 'k' }, 546 { "offset", required_argument, NULL, 'o' }, 547 { "read-only", no_argument, NULL, 'r' }, 548 { "allocation-depth", no_argument, NULL, 'A' }, 549 { "bitmap", required_argument, NULL, 'B' }, 550 { "connect", required_argument, NULL, 'c' }, 551 { "disconnect", no_argument, NULL, 'd' }, 552 { "list", no_argument, NULL, 'L' }, 553 { "snapshot", no_argument, NULL, 's' }, 554 { "load-snapshot", required_argument, NULL, 'l' }, 555 { "nocache", no_argument, NULL, 'n' }, 556 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 557 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 558 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 559 { "detect-zeroes", required_argument, NULL, 560 QEMU_NBD_OPT_DETECT_ZEROES }, 561 { "shared", required_argument, NULL, 'e' }, 562 { "format", required_argument, NULL, 'f' }, 563 { "persistent", no_argument, NULL, 't' }, 564 { "verbose", no_argument, NULL, 'v' }, 565 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 566 { "export-name", required_argument, NULL, 'x' }, 567 { "description", required_argument, NULL, 'D' }, 568 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 569 { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME }, 570 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 571 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 572 { "trace", required_argument, NULL, 'T' }, 573 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 574 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 575 { "selinux-label", required_argument, NULL, 576 QEMU_NBD_OPT_SELINUX_LABEL }, 577 { NULL, 0, NULL, 0 } 578 }; 579 int ch; 580 int opt_ind = 0; 581 int flags = BDRV_O_RDWR; 582 int ret = 0; 583 bool seen_cache = false; 584 bool seen_discard = false; 585 bool seen_aio = false; 586 pthread_t client_thread; 587 const char *fmt = NULL; 588 Error *local_err = NULL; 589 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 590 QDict *options = NULL; 591 const char *export_name = NULL; /* defaults to "" later for server mode */ 592 const char *export_description = NULL; 593 BlockDirtyBitmapOrStrList *bitmaps = NULL; 594 bool alloc_depth = false; 595 const char *tlscredsid = NULL; 596 const char *tlshostname = NULL; 597 bool imageOpts = false; 598 bool writethrough = false; /* Client will flush as needed. */ 599 bool list = false; 600 unsigned socket_activation; 601 const char *pid_file_name = NULL; 602 const char *selinux_label = NULL; 603 BlockExportOptions *export_opts; 604 struct NbdClientOpts opts = { 605 .fork_process = false, 606 .verbose = false, 607 .device = NULL, 608 .srcpath = NULL, 609 .saddr = NULL, 610 .old_stderr = STDOUT_FILENO, 611 }; 612 613 #ifdef CONFIG_POSIX 614 os_setup_early_signal_handling(); 615 os_setup_signal_handling(); 616 #endif 617 618 socket_init(); 619 error_init(argv[0]); 620 module_call_init(MODULE_INIT_TRACE); 621 qcrypto_init(&error_fatal); 622 623 module_call_init(MODULE_INIT_QOM); 624 qemu_add_opts(&qemu_trace_opts); 625 qemu_init_exec_dir(argv[0]); 626 627 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 628 switch (ch) { 629 case 's': 630 flags |= BDRV_O_SNAPSHOT; 631 break; 632 case 'n': 633 optarg = (char *) "none"; 634 /* fallthrough */ 635 case QEMU_NBD_OPT_CACHE: 636 if (seen_cache) { 637 error_report("-n and --cache can only be specified once"); 638 exit(EXIT_FAILURE); 639 } 640 seen_cache = true; 641 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 642 error_report("Invalid cache mode `%s'", optarg); 643 exit(EXIT_FAILURE); 644 } 645 break; 646 case QEMU_NBD_OPT_AIO: 647 if (seen_aio) { 648 error_report("--aio can only be specified once"); 649 exit(EXIT_FAILURE); 650 } 651 seen_aio = true; 652 if (bdrv_parse_aio(optarg, &flags) < 0) { 653 error_report("Invalid aio mode '%s'", optarg); 654 exit(EXIT_FAILURE); 655 } 656 break; 657 case QEMU_NBD_OPT_DISCARD: 658 if (seen_discard) { 659 error_report("--discard can only be specified once"); 660 exit(EXIT_FAILURE); 661 } 662 seen_discard = true; 663 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 664 error_report("Invalid discard mode `%s'", optarg); 665 exit(EXIT_FAILURE); 666 } 667 break; 668 case QEMU_NBD_OPT_DETECT_ZEROES: 669 detect_zeroes = 670 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 671 optarg, 672 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 673 &local_err); 674 if (local_err) { 675 error_reportf_err(local_err, 676 "Failed to parse detect_zeroes mode: "); 677 exit(EXIT_FAILURE); 678 } 679 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 680 !(flags & BDRV_O_UNMAP)) { 681 error_report("setting detect-zeroes to unmap is not allowed " 682 "without setting discard operation to unmap"); 683 exit(EXIT_FAILURE); 684 } 685 break; 686 case 'b': 687 bindto = optarg; 688 break; 689 case 'p': 690 port = optarg; 691 break; 692 case 'o': 693 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 694 error_report("Invalid offset '%s'", optarg); 695 exit(EXIT_FAILURE); 696 } 697 break; 698 case 'l': 699 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 700 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 701 optarg, false); 702 if (!sn_opts) { 703 error_report("Failed in parsing snapshot param `%s'", 704 optarg); 705 exit(EXIT_FAILURE); 706 } 707 } else { 708 sn_id_or_name = optarg; 709 } 710 /* fall through */ 711 case 'r': 712 readonly = true; 713 flags &= ~BDRV_O_RDWR; 714 break; 715 case 'A': 716 alloc_depth = true; 717 break; 718 case 'B': 719 { 720 BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1); 721 *el = (BlockDirtyBitmapOrStr) { 722 .type = QTYPE_QSTRING, 723 .u.local = g_strdup(optarg), 724 }; 725 QAPI_LIST_PREPEND(bitmaps, el); 726 } 727 break; 728 case 'k': 729 sockpath = optarg; 730 if (sockpath[0] != '/') { 731 error_report("socket path must be absolute"); 732 exit(EXIT_FAILURE); 733 } 734 break; 735 case 'd': 736 disconnect = true; 737 break; 738 case 'c': 739 opts.device = optarg; 740 break; 741 case 'e': 742 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 743 shared < 0) { 744 error_report("Invalid shared device number '%s'", optarg); 745 exit(EXIT_FAILURE); 746 } 747 break; 748 case 'f': 749 fmt = optarg; 750 break; 751 case 't': 752 persistent = 1; 753 break; 754 case 'x': 755 export_name = optarg; 756 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 757 error_report("export name '%s' too long", export_name); 758 exit(EXIT_FAILURE); 759 } 760 break; 761 case 'D': 762 export_description = optarg; 763 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 764 error_report("export description '%s' too long", 765 export_description); 766 exit(EXIT_FAILURE); 767 } 768 break; 769 case 'v': 770 opts.verbose = true; 771 break; 772 case 'V': 773 version(argv[0]); 774 exit(0); 775 break; 776 case 'h': 777 usage(argv[0]); 778 exit(0); 779 break; 780 case '?': 781 error_report("Try `%s --help' for more information.", argv[0]); 782 exit(EXIT_FAILURE); 783 case QEMU_NBD_OPT_OBJECT: 784 user_creatable_process_cmdline(optarg); 785 break; 786 case QEMU_NBD_OPT_TLSCREDS: 787 tlscredsid = optarg; 788 break; 789 case QEMU_NBD_OPT_TLSHOSTNAME: 790 tlshostname = optarg; 791 break; 792 case QEMU_NBD_OPT_IMAGE_OPTS: 793 imageOpts = true; 794 break; 795 case 'T': 796 trace_opt_parse(optarg); 797 break; 798 case QEMU_NBD_OPT_TLSAUTHZ: 799 tlsauthz = optarg; 800 break; 801 case QEMU_NBD_OPT_FORK: 802 opts.fork_process = true; 803 break; 804 case 'L': 805 list = true; 806 break; 807 case QEMU_NBD_OPT_PID_FILE: 808 pid_file_name = optarg; 809 break; 810 case QEMU_NBD_OPT_SELINUX_LABEL: 811 selinux_label = optarg; 812 break; 813 } 814 } 815 816 if (list) { 817 if (argc != optind) { 818 error_report("List mode is incompatible with a file name"); 819 exit(EXIT_FAILURE); 820 } 821 if (export_name || export_description || dev_offset || 822 opts.device || disconnect || fmt || sn_id_or_name || bitmaps || 823 alloc_depth || seen_aio || seen_discard || seen_cache) { 824 error_report("List mode is incompatible with per-device settings"); 825 exit(EXIT_FAILURE); 826 } 827 if (opts.fork_process) { 828 error_report("List mode is incompatible with forking"); 829 exit(EXIT_FAILURE); 830 } 831 } else if ((argc - optind) != 1) { 832 error_report("Invalid number of arguments"); 833 error_printf("Try `%s --help' for more information.\n", argv[0]); 834 exit(EXIT_FAILURE); 835 } else if (!export_name) { 836 export_name = ""; 837 } 838 839 if (!trace_init_backends()) { 840 exit(1); 841 } 842 trace_init_file(); 843 qemu_set_log(LOG_TRACE, &error_fatal); 844 845 socket_activation = check_socket_activation(); 846 if (socket_activation == 0) { 847 if (!sockpath) { 848 setup_address_and_port(&bindto, &port); 849 } 850 } else { 851 /* Using socket activation - check user didn't use -p etc. */ 852 const char *err_msg = socket_activation_validate_opts(opts.device, 853 sockpath, 854 bindto, port, 855 selinux_label, 856 list); 857 if (err_msg != NULL) { 858 error_report("%s", err_msg); 859 exit(EXIT_FAILURE); 860 } 861 862 /* qemu-nbd can only listen on a single socket. */ 863 if (socket_activation > 1) { 864 error_report("qemu-nbd does not support socket activation with %s > 1", 865 "LISTEN_FDS"); 866 exit(EXIT_FAILURE); 867 } 868 } 869 870 if (tlscredsid) { 871 if (opts.device) { 872 error_report("TLS is not supported with a host device"); 873 exit(EXIT_FAILURE); 874 } 875 if (tlsauthz && list) { 876 error_report("TLS authorization is incompatible with export list"); 877 exit(EXIT_FAILURE); 878 } 879 if (tlshostname && !list) { 880 error_report("TLS hostname is only supported with export list"); 881 exit(EXIT_FAILURE); 882 } 883 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 884 if (local_err) { 885 error_reportf_err(local_err, "Failed to get TLS creds: "); 886 exit(EXIT_FAILURE); 887 } 888 } else { 889 if (tlsauthz) { 890 error_report("--tls-authz is not permitted without --tls-creds"); 891 exit(EXIT_FAILURE); 892 } 893 if (tlshostname) { 894 error_report("--tls-hostname is not permitted without --tls-creds"); 895 exit(EXIT_FAILURE); 896 } 897 } 898 899 if (selinux_label) { 900 #ifdef CONFIG_SELINUX 901 if (sockpath == NULL && opts.device == NULL) { 902 error_report("--selinux-label is not permitted without --socket"); 903 exit(EXIT_FAILURE); 904 } 905 #else 906 error_report("SELinux support not enabled in this binary"); 907 exit(EXIT_FAILURE); 908 #endif 909 } 910 911 if (list) { 912 opts.saddr = nbd_build_socket_address(sockpath, bindto, port); 913 return qemu_nbd_client_list(opts.saddr, tlscreds, 914 tlshostname ? tlshostname : bindto); 915 } 916 917 #if !HAVE_NBD_DEVICE 918 if (disconnect || opts.device) { 919 error_report("Kernel /dev/nbdN support not available"); 920 exit(EXIT_FAILURE); 921 } 922 #else /* HAVE_NBD_DEVICE */ 923 if (disconnect) { 924 int nbdfd = open(argv[optind], O_RDWR); 925 if (nbdfd < 0) { 926 error_report("Cannot open %s: %s", argv[optind], 927 strerror(errno)); 928 exit(EXIT_FAILURE); 929 } 930 nbd_disconnect(nbdfd); 931 932 close(nbdfd); 933 934 printf("%s disconnected\n", argv[optind]); 935 936 return 0; 937 } 938 #endif 939 940 if ((opts.device && !opts.verbose) || opts.fork_process) { 941 #ifndef WIN32 942 g_autoptr(GError) err = NULL; 943 int stderr_fd[2]; 944 pid_t pid; 945 946 if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) { 947 error_report("Error setting up communication pipe: %s", 948 err->message); 949 exit(EXIT_FAILURE); 950 } 951 952 /* Now daemonize, but keep a communication channel open to 953 * print errors and exit with the proper status code. 954 */ 955 pid = fork(); 956 if (pid < 0) { 957 error_report("Failed to fork: %s", strerror(errno)); 958 exit(EXIT_FAILURE); 959 } else if (pid == 0) { 960 int saved_errno; 961 962 close(stderr_fd[0]); 963 964 /* Remember parent's stderr if we will be restoring it. */ 965 if (opts.verbose /* fork_process is set */) { 966 opts.old_stderr = dup(STDERR_FILENO); 967 if (opts.old_stderr < 0) { 968 error_report("Could not dup original stderr: %s", 969 strerror(errno)); 970 exit(EXIT_FAILURE); 971 } 972 } 973 974 ret = qemu_daemon(1, 0); 975 saved_errno = errno; /* dup2 will overwrite error below */ 976 977 /* Temporarily redirect stderr to the parent's pipe... */ 978 if (dup2(stderr_fd[1], STDERR_FILENO) < 0) { 979 char str[256]; 980 snprintf(str, sizeof(str), 981 "%s: Failed to link stderr to the pipe: %s\n", 982 g_get_prgname(), strerror(errno)); 983 /* 984 * We are unable to use error_report() here as we need to get 985 * stderr pointed to the parent's pipe. Write to that pipe 986 * manually. 987 */ 988 ret = write(stderr_fd[1], str, strlen(str)); 989 exit(EXIT_FAILURE); 990 } 991 992 if (ret < 0) { 993 error_report("Failed to daemonize: %s", strerror(saved_errno)); 994 exit(EXIT_FAILURE); 995 } 996 997 /* ... close the descriptor we inherited and go on. */ 998 close(stderr_fd[1]); 999 } else { 1000 bool errors = false; 1001 char *buf; 1002 1003 /* In the parent. Print error messages from the child until 1004 * it closes the pipe. 1005 */ 1006 close(stderr_fd[1]); 1007 buf = g_malloc(1024); 1008 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 1009 errors = true; 1010 ret = qemu_write_full(STDERR_FILENO, buf, ret); 1011 if (ret < 0) { 1012 exit(EXIT_FAILURE); 1013 } 1014 } 1015 if (ret < 0) { 1016 error_report("Cannot read from daemon: %s", 1017 strerror(errno)); 1018 exit(EXIT_FAILURE); 1019 } 1020 1021 /* Usually the daemon should not print any message. 1022 * Exit with zero status in that case. 1023 */ 1024 exit(errors); 1025 } 1026 #else /* WIN32 */ 1027 error_report("Unable to fork into background on Windows hosts"); 1028 exit(EXIT_FAILURE); 1029 #endif /* WIN32 */ 1030 } 1031 1032 if (opts.device != NULL && sockpath == NULL) { 1033 sockpath = g_malloc(128); 1034 snprintf(sockpath, 128, SOCKET_PATH, basename(opts.device)); 1035 } 1036 1037 server = qio_net_listener_new(); 1038 if (socket_activation == 0) { 1039 int backlog; 1040 1041 if (persistent || shared == 0) { 1042 backlog = SOMAXCONN; 1043 } else { 1044 backlog = MIN(shared, SOMAXCONN); 1045 } 1046 #ifdef CONFIG_SELINUX 1047 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) { 1048 error_report("Cannot set SELinux socket create context to %s: %s", 1049 selinux_label, strerror(errno)); 1050 exit(EXIT_FAILURE); 1051 } 1052 #endif 1053 opts.saddr = nbd_build_socket_address(sockpath, bindto, port); 1054 if (qio_net_listener_open_sync(server, opts.saddr, backlog, 1055 &local_err) < 0) { 1056 object_unref(OBJECT(server)); 1057 error_report_err(local_err); 1058 exit(EXIT_FAILURE); 1059 } 1060 #ifdef CONFIG_SELINUX 1061 if (selinux_label && setsockcreatecon_raw(NULL) == -1) { 1062 error_report("Cannot clear SELinux socket create context: %s", 1063 strerror(errno)); 1064 exit(EXIT_FAILURE); 1065 } 1066 #endif 1067 } else { 1068 size_t i; 1069 /* See comment in check_socket_activation above. */ 1070 for (i = 0; i < socket_activation; i++) { 1071 QIOChannelSocket *sioc; 1072 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 1073 &local_err); 1074 if (sioc == NULL) { 1075 object_unref(OBJECT(server)); 1076 error_reportf_err(local_err, 1077 "Failed to use socket activation: "); 1078 exit(EXIT_FAILURE); 1079 } 1080 qio_net_listener_add(server, sioc); 1081 object_unref(OBJECT(sioc)); 1082 } 1083 } 1084 1085 qemu_init_main_loop(&error_fatal); 1086 bdrv_init(); 1087 atexit(qemu_nbd_shutdown); 1088 1089 opts.srcpath = argv[optind]; 1090 if (imageOpts) { 1091 QemuOpts *o; 1092 if (fmt) { 1093 error_report("--image-opts and -f are mutually exclusive"); 1094 exit(EXIT_FAILURE); 1095 } 1096 o = qemu_opts_parse_noisily(&file_opts, opts.srcpath, true); 1097 if (!o) { 1098 qemu_opts_reset(&file_opts); 1099 exit(EXIT_FAILURE); 1100 } 1101 options = qemu_opts_to_qdict(o, NULL); 1102 qemu_opts_reset(&file_opts); 1103 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1104 } else { 1105 if (fmt) { 1106 options = qdict_new(); 1107 qdict_put_str(options, "driver", fmt); 1108 } 1109 blk = blk_new_open(opts.srcpath, NULL, options, flags, &local_err); 1110 } 1111 1112 if (!blk) { 1113 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1114 argv[optind]); 1115 exit(EXIT_FAILURE); 1116 } 1117 bs = blk_bs(blk); 1118 1119 if (dev_offset) { 1120 QDict *raw_opts = qdict_new(); 1121 qdict_put_str(raw_opts, "driver", "raw"); 1122 qdict_put_str(raw_opts, "file", bs->node_name); 1123 qdict_put_int(raw_opts, "offset", dev_offset); 1124 1125 aio_context_acquire(qemu_get_aio_context()); 1126 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1127 aio_context_release(qemu_get_aio_context()); 1128 1129 blk_remove_bs(blk); 1130 blk_insert_bs(blk, bs, &error_fatal); 1131 bdrv_unref(bs); 1132 } 1133 1134 blk_set_enable_write_cache(blk, !writethrough); 1135 1136 if (sn_opts) { 1137 ret = bdrv_snapshot_load_tmp(bs, 1138 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1139 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1140 &local_err); 1141 } else if (sn_id_or_name) { 1142 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1143 &local_err); 1144 } 1145 if (ret < 0) { 1146 error_reportf_err(local_err, "Failed to load snapshot: "); 1147 exit(EXIT_FAILURE); 1148 } 1149 1150 bs->detect_zeroes = detect_zeroes; 1151 1152 nbd_server_is_qemu_nbd(shared); 1153 1154 export_opts = g_new(BlockExportOptions, 1); 1155 *export_opts = (BlockExportOptions) { 1156 .type = BLOCK_EXPORT_TYPE_NBD, 1157 .id = g_strdup("qemu-nbd-export"), 1158 .node_name = g_strdup(bdrv_get_node_name(bs)), 1159 .has_writethrough = true, 1160 .writethrough = writethrough, 1161 .has_writable = true, 1162 .writable = !readonly, 1163 .u.nbd = { 1164 .name = g_strdup(export_name), 1165 .description = g_strdup(export_description), 1166 .has_bitmaps = !!bitmaps, 1167 .bitmaps = bitmaps, 1168 .has_allocation_depth = alloc_depth, 1169 .allocation_depth = alloc_depth, 1170 }, 1171 }; 1172 blk_exp_add(export_opts, &error_fatal); 1173 qapi_free_BlockExportOptions(export_opts); 1174 1175 if (opts.device) { 1176 #if HAVE_NBD_DEVICE 1177 ret = pthread_create(&client_thread, NULL, nbd_client_thread, &opts); 1178 if (ret != 0) { 1179 error_report("Failed to create client thread: %s", strerror(ret)); 1180 exit(EXIT_FAILURE); 1181 } 1182 #endif 1183 } else { 1184 /* Shut up GCC warnings. */ 1185 memset(&client_thread, 0, sizeof(client_thread)); 1186 } 1187 1188 nbd_update_server_watch(); 1189 1190 if (pid_file_name) { 1191 qemu_write_pidfile(pid_file_name, &error_fatal); 1192 } 1193 1194 /* now when the initialization is (almost) complete, chdir("/") 1195 * to free any busy filesystems */ 1196 if (chdir("/") < 0) { 1197 error_report("Could not chdir to root directory: %s", 1198 strerror(errno)); 1199 exit(EXIT_FAILURE); 1200 } 1201 1202 if (opts.fork_process) { 1203 nbd_client_release_pipe(opts.old_stderr); 1204 } 1205 1206 state = RUNNING; 1207 do { 1208 main_loop_wait(false); 1209 if (state == TERMINATE) { 1210 blk_exp_close_all(); 1211 state = TERMINATED; 1212 } 1213 } while (state != TERMINATED); 1214 1215 blk_unref(blk); 1216 if (sockpath) { 1217 unlink(sockpath); 1218 } 1219 1220 qemu_opts_del(sn_opts); 1221 1222 if (opts.device) { 1223 void *result; 1224 pthread_join(client_thread, &result); 1225 ret = (intptr_t)result; 1226 exit(ret); 1227 } else { 1228 exit(EXIT_SUCCESS); 1229 } 1230 } 1231