qemu-nbd.c (38560B)
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 verbose; 77 static char *srcpath; 78 static SocketAddress *saddr; 79 static int persistent = 0; 80 static enum { RUNNING, TERMINATE, TERMINATED } state; 81 static int shared = 1; 82 static int nb_fds; 83 static QIONetListener *server; 84 static QCryptoTLSCreds *tlscreds; 85 static const char *tlsauthz; 86 87 static void usage(const char *name) 88 { 89 (printf) ( 90 "Usage: %s [OPTIONS] FILE\n" 91 " or: %s -L [OPTIONS]\n" 92 "QEMU Disk Network Block Device Utility\n" 93 "\n" 94 " -h, --help display this help and exit\n" 95 " -V, --version output version information and exit\n" 96 "\n" 97 "Connection properties:\n" 98 " -p, --port=PORT port to listen on (default `%d')\n" 99 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 100 " -k, --socket=PATH path to the unix socket\n" 101 " (default '"SOCKET_PATH"')\n" 102 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 103 " -t, --persistent don't exit on the last connection\n" 104 " -v, --verbose display extra debugging information\n" 105 " -x, --export-name=NAME expose export by name (default is empty string)\n" 106 " -D, --description=TEXT export a human-readable description\n" 107 "\n" 108 "Exposing part of the image:\n" 109 " -o, --offset=OFFSET offset into the image\n" 110 " -A, --allocation-depth expose the allocation depth\n" 111 " -B, --bitmap=NAME expose a persistent dirty bitmap\n" 112 "\n" 113 "General purpose options:\n" 114 " -L, --list list exports available from another NBD server\n" 115 " --object type,id=ID,... define an object such as 'secret' for providing\n" 116 " passwords and/or encryption keys\n" 117 " --tls-creds=ID use id of an earlier --object to provide TLS\n" 118 " --tls-authz=ID use id of an earlier --object to provide\n" 119 " authorization\n" 120 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 121 " specify tracing options\n" 122 " --fork fork off the server process and exit the parent\n" 123 " once the server is running\n" 124 " --pid-file=PATH store the server's process ID in the given file\n" 125 #ifdef CONFIG_SELINUX 126 " --selinux-label=LABEL set SELinux process label on listening socket\n" 127 #endif 128 #if HAVE_NBD_DEVICE 129 "\n" 130 "Kernel NBD client support:\n" 131 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 132 " -d, --disconnect disconnect the specified device\n" 133 #endif 134 "\n" 135 "Block device options:\n" 136 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 137 " -r, --read-only export read-only\n" 138 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 139 " file with backing_file=FILE, redirect the write to\n" 140 " the temporary one\n" 141 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 142 " load an internal snapshot inside FILE and export it\n" 143 " as an read-only device, SNAPSHOT_PARAM format is\n" 144 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 145 " '[ID_OR_NAME]'\n" 146 " -n, --nocache disable host cache\n" 147 " --cache=MODE set cache mode used to access the disk image, the\n" 148 " valid options are: 'none', 'writeback' (default),\n" 149 " 'writethrough', 'directsync' and 'unsafe'\n" 150 " --aio=MODE set AIO mode (native, io_uring or threads)\n" 151 " --discard=MODE set discard mode (ignore, unmap)\n" 152 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 153 " --image-opts treat FILE as a full set of image options\n" 154 "\n" 155 QEMU_HELP_BOTTOM "\n" 156 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 157 } 158 159 static void version(const char *name) 160 { 161 printf( 162 "%s " QEMU_FULL_VERSION "\n" 163 "Written by Anthony Liguori.\n" 164 "\n" 165 QEMU_COPYRIGHT "\n" 166 "This is free software; see the source for copying conditions. There is NO\n" 167 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 168 , name); 169 } 170 171 #ifdef CONFIG_POSIX 172 /* 173 * The client thread uses SIGTERM to interrupt the server. A signal 174 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 175 */ 176 void qemu_system_killed(int signum, pid_t pid) 177 { 178 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 179 qemu_notify_event(); 180 } 181 #endif /* CONFIG_POSIX */ 182 183 static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 184 const char *hostname) 185 { 186 int ret = EXIT_FAILURE; 187 int rc; 188 Error *err = NULL; 189 QIOChannelSocket *sioc; 190 NBDExportInfo *list; 191 int i, j; 192 193 sioc = qio_channel_socket_new(); 194 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 195 error_report_err(err); 196 goto out; 197 } 198 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 199 &err); 200 if (rc < 0) { 201 if (err) { 202 error_report_err(err); 203 } 204 goto out; 205 } 206 printf("exports available: %d\n", rc); 207 for (i = 0; i < rc; i++) { 208 printf(" export: '%s'\n", list[i].name); 209 if (list[i].description && *list[i].description) { 210 printf(" description: %s\n", list[i].description); 211 } 212 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 213 static const char *const flag_names[] = { 214 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 215 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 216 [NBD_FLAG_SEND_FUA_BIT] = "fua", 217 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 218 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 219 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 220 [NBD_FLAG_SEND_DF_BIT] = "df", 221 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 222 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 223 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 224 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 225 }; 226 227 printf(" size: %" PRIu64 "\n", list[i].size); 228 printf(" flags: 0x%x (", list[i].flags); 229 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 230 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 231 printf(" %s", flag_names[bit]); 232 } 233 } 234 printf(" )\n"); 235 } 236 if (list[i].min_block) { 237 printf(" min block: %u\n", list[i].min_block); 238 printf(" opt block: %u\n", list[i].opt_block); 239 printf(" max block: %u\n", list[i].max_block); 240 } 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 #if HAVE_NBD_DEVICE 258 static void *show_parts(void *arg) 259 { 260 char *device = arg; 261 int nbd; 262 263 /* linux just needs an open() to trigger 264 * the partition table update 265 * but remember to load the module with max_part != 0 : 266 * modprobe nbd max_part=63 267 */ 268 nbd = open(device, O_RDWR); 269 if (nbd >= 0) { 270 close(nbd); 271 } 272 return NULL; 273 } 274 275 static void *nbd_client_thread(void *arg) 276 { 277 char *device = arg; 278 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 279 QIOChannelSocket *sioc; 280 int fd = -1; 281 int ret = EXIT_FAILURE; 282 pthread_t show_parts_thread; 283 Error *local_error = NULL; 284 285 sioc = qio_channel_socket_new(); 286 if (qio_channel_socket_connect_sync(sioc, 287 saddr, 288 &local_error) < 0) { 289 error_report_err(local_error); 290 goto out; 291 } 292 293 if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 294 NULL, NULL, NULL, &info, &local_error) < 0) { 295 if (local_error) { 296 error_report_err(local_error); 297 } 298 goto out; 299 } 300 301 fd = open(device, O_RDWR); 302 if (fd < 0) { 303 /* Linux-only, we can use %m in printf. */ 304 error_report("Failed to open %s: %m", device); 305 goto out; 306 } 307 308 if (nbd_init(fd, sioc, &info, &local_error) < 0) { 309 error_report_err(local_error); 310 goto out; 311 } 312 313 /* update partition table */ 314 pthread_create(&show_parts_thread, NULL, show_parts, device); 315 316 if (verbose) { 317 fprintf(stderr, "NBD device %s is now connected to %s\n", 318 device, srcpath); 319 } else { 320 /* Close stderr so that the qemu-nbd process exits. */ 321 dup2(STDOUT_FILENO, STDERR_FILENO); 322 } 323 324 if (nbd_client(fd) < 0) { 325 goto out; 326 } 327 328 ret = EXIT_SUCCESS; 329 330 out: 331 if (fd >= 0) { 332 close(fd); 333 } 334 object_unref(OBJECT(sioc)); 335 g_free(info.name); 336 kill(getpid(), SIGTERM); 337 return (void *) (intptr_t) ret; 338 } 339 #endif /* HAVE_NBD_DEVICE */ 340 341 static int nbd_can_accept(void) 342 { 343 return state == RUNNING && (shared == 0 || nb_fds < shared); 344 } 345 346 static void nbd_update_server_watch(void); 347 348 static void nbd_client_closed(NBDClient *client, bool negotiated) 349 { 350 nb_fds--; 351 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 352 state = TERMINATE; 353 } 354 nbd_update_server_watch(); 355 nbd_client_put(client); 356 } 357 358 static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 359 gpointer opaque) 360 { 361 if (state >= TERMINATE) { 362 return; 363 } 364 365 nb_fds++; 366 nbd_update_server_watch(); 367 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 368 } 369 370 static void nbd_update_server_watch(void) 371 { 372 if (nbd_can_accept()) { 373 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 374 } else { 375 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 376 } 377 } 378 379 380 static SocketAddress *nbd_build_socket_address(const char *sockpath, 381 const char *bindto, 382 const char *port) 383 { 384 SocketAddress *saddr; 385 386 saddr = g_new0(SocketAddress, 1); 387 if (sockpath) { 388 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 389 saddr->u.q_unix.path = g_strdup(sockpath); 390 } else { 391 InetSocketAddress *inet; 392 saddr->type = SOCKET_ADDRESS_TYPE_INET; 393 inet = &saddr->u.inet; 394 inet->host = g_strdup(bindto); 395 if (port) { 396 inet->port = g_strdup(port); 397 } else { 398 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 399 } 400 } 401 402 return saddr; 403 } 404 405 406 static QemuOptsList file_opts = { 407 .name = "file", 408 .implied_opt_name = "file", 409 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 410 .desc = { 411 /* no elements => accept any params */ 412 { /* end of list */ } 413 }, 414 }; 415 416 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 417 Error **errp) 418 { 419 Object *obj; 420 QCryptoTLSCreds *creds; 421 422 obj = object_resolve_path_component( 423 object_get_objects_root(), id); 424 if (!obj) { 425 error_setg(errp, "No TLS credentials with id '%s'", 426 id); 427 return NULL; 428 } 429 creds = (QCryptoTLSCreds *) 430 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 431 if (!creds) { 432 error_setg(errp, "Object with id '%s' is not TLS credentials", 433 id); 434 return NULL; 435 } 436 437 if (!qcrypto_tls_creds_check_endpoint(creds, 438 list 439 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT 440 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, 441 errp)) { 442 return NULL; 443 } 444 object_ref(obj); 445 return creds; 446 } 447 448 static void setup_address_and_port(const char **address, const char **port) 449 { 450 if (*address == NULL) { 451 *address = "0.0.0.0"; 452 } 453 454 if (*port == NULL) { 455 *port = stringify(NBD_DEFAULT_PORT); 456 } 457 } 458 459 /* 460 * Check socket parameters compatibility when socket activation is used. 461 */ 462 static const char *socket_activation_validate_opts(const char *device, 463 const char *sockpath, 464 const char *address, 465 const char *port, 466 const char *selinux, 467 bool list) 468 { 469 if (device != NULL) { 470 return "NBD device can't be set when using socket activation"; 471 } 472 473 if (sockpath != NULL) { 474 return "Unix socket can't be set when using socket activation"; 475 } 476 477 if (address != NULL) { 478 return "The interface can't be set when using socket activation"; 479 } 480 481 if (port != NULL) { 482 return "TCP port number can't be set when using socket activation"; 483 } 484 485 if (selinux != NULL) { 486 return "SELinux label can't be set when using socket activation"; 487 } 488 489 if (list) { 490 return "List mode is incompatible with socket activation"; 491 } 492 493 return NULL; 494 } 495 496 static void qemu_nbd_shutdown(void) 497 { 498 job_cancel_sync_all(); 499 blk_exp_close_all(); 500 bdrv_close_all(); 501 } 502 503 int main(int argc, char **argv) 504 { 505 BlockBackend *blk; 506 BlockDriverState *bs; 507 uint64_t dev_offset = 0; 508 bool readonly = false; 509 bool disconnect = false; 510 const char *bindto = NULL; 511 const char *port = NULL; 512 char *sockpath = NULL; 513 char *device = NULL; 514 QemuOpts *sn_opts = NULL; 515 const char *sn_id_or_name = NULL; 516 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 517 struct option lopt[] = { 518 { "help", no_argument, NULL, 'h' }, 519 { "version", no_argument, NULL, 'V' }, 520 { "bind", required_argument, NULL, 'b' }, 521 { "port", required_argument, NULL, 'p' }, 522 { "socket", required_argument, NULL, 'k' }, 523 { "offset", required_argument, NULL, 'o' }, 524 { "read-only", no_argument, NULL, 'r' }, 525 { "allocation-depth", no_argument, NULL, 'A' }, 526 { "bitmap", required_argument, NULL, 'B' }, 527 { "connect", required_argument, NULL, 'c' }, 528 { "disconnect", no_argument, NULL, 'd' }, 529 { "list", no_argument, NULL, 'L' }, 530 { "snapshot", no_argument, NULL, 's' }, 531 { "load-snapshot", required_argument, NULL, 'l' }, 532 { "nocache", no_argument, NULL, 'n' }, 533 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 534 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 535 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 536 { "detect-zeroes", required_argument, NULL, 537 QEMU_NBD_OPT_DETECT_ZEROES }, 538 { "shared", required_argument, NULL, 'e' }, 539 { "format", required_argument, NULL, 'f' }, 540 { "persistent", no_argument, NULL, 't' }, 541 { "verbose", no_argument, NULL, 'v' }, 542 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 543 { "export-name", required_argument, NULL, 'x' }, 544 { "description", required_argument, NULL, 'D' }, 545 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 546 { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME }, 547 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 548 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 549 { "trace", required_argument, NULL, 'T' }, 550 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 551 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 552 { "selinux-label", required_argument, NULL, 553 QEMU_NBD_OPT_SELINUX_LABEL }, 554 { NULL, 0, NULL, 0 } 555 }; 556 int ch; 557 int opt_ind = 0; 558 int flags = BDRV_O_RDWR; 559 int ret = 0; 560 bool seen_cache = false; 561 bool seen_discard = false; 562 bool seen_aio = false; 563 pthread_t client_thread; 564 const char *fmt = NULL; 565 Error *local_err = NULL; 566 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 567 QDict *options = NULL; 568 const char *export_name = NULL; /* defaults to "" later for server mode */ 569 const char *export_description = NULL; 570 BlockDirtyBitmapOrStrList *bitmaps = NULL; 571 bool alloc_depth = false; 572 const char *tlscredsid = NULL; 573 const char *tlshostname = NULL; 574 bool imageOpts = false; 575 bool writethrough = false; /* Client will flush as needed. */ 576 bool fork_process = false; 577 bool list = false; 578 int old_stderr = -1; 579 unsigned socket_activation; 580 const char *pid_file_name = NULL; 581 const char *selinux_label = NULL; 582 BlockExportOptions *export_opts; 583 584 #ifdef CONFIG_POSIX 585 os_setup_early_signal_handling(); 586 os_setup_signal_handling(); 587 #endif 588 589 socket_init(); 590 error_init(argv[0]); 591 module_call_init(MODULE_INIT_TRACE); 592 qcrypto_init(&error_fatal); 593 594 module_call_init(MODULE_INIT_QOM); 595 qemu_add_opts(&qemu_trace_opts); 596 qemu_init_exec_dir(argv[0]); 597 598 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 599 switch (ch) { 600 case 's': 601 flags |= BDRV_O_SNAPSHOT; 602 break; 603 case 'n': 604 optarg = (char *) "none"; 605 /* fallthrough */ 606 case QEMU_NBD_OPT_CACHE: 607 if (seen_cache) { 608 error_report("-n and --cache can only be specified once"); 609 exit(EXIT_FAILURE); 610 } 611 seen_cache = true; 612 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 613 error_report("Invalid cache mode `%s'", optarg); 614 exit(EXIT_FAILURE); 615 } 616 break; 617 case QEMU_NBD_OPT_AIO: 618 if (seen_aio) { 619 error_report("--aio can only be specified once"); 620 exit(EXIT_FAILURE); 621 } 622 seen_aio = true; 623 if (bdrv_parse_aio(optarg, &flags) < 0) { 624 error_report("Invalid aio mode '%s'", optarg); 625 exit(EXIT_FAILURE); 626 } 627 break; 628 case QEMU_NBD_OPT_DISCARD: 629 if (seen_discard) { 630 error_report("--discard can only be specified once"); 631 exit(EXIT_FAILURE); 632 } 633 seen_discard = true; 634 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 635 error_report("Invalid discard mode `%s'", optarg); 636 exit(EXIT_FAILURE); 637 } 638 break; 639 case QEMU_NBD_OPT_DETECT_ZEROES: 640 detect_zeroes = 641 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 642 optarg, 643 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 644 &local_err); 645 if (local_err) { 646 error_reportf_err(local_err, 647 "Failed to parse detect_zeroes mode: "); 648 exit(EXIT_FAILURE); 649 } 650 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 651 !(flags & BDRV_O_UNMAP)) { 652 error_report("setting detect-zeroes to unmap is not allowed " 653 "without setting discard operation to unmap"); 654 exit(EXIT_FAILURE); 655 } 656 break; 657 case 'b': 658 bindto = optarg; 659 break; 660 case 'p': 661 port = optarg; 662 break; 663 case 'o': 664 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 665 error_report("Invalid offset '%s'", optarg); 666 exit(EXIT_FAILURE); 667 } 668 break; 669 case 'l': 670 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 671 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 672 optarg, false); 673 if (!sn_opts) { 674 error_report("Failed in parsing snapshot param `%s'", 675 optarg); 676 exit(EXIT_FAILURE); 677 } 678 } else { 679 sn_id_or_name = optarg; 680 } 681 /* fall through */ 682 case 'r': 683 readonly = true; 684 flags &= ~BDRV_O_RDWR; 685 break; 686 case 'A': 687 alloc_depth = true; 688 break; 689 case 'B': 690 { 691 BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1); 692 *el = (BlockDirtyBitmapOrStr) { 693 .type = QTYPE_QSTRING, 694 .u.local = g_strdup(optarg), 695 }; 696 QAPI_LIST_PREPEND(bitmaps, el); 697 } 698 break; 699 case 'k': 700 sockpath = optarg; 701 if (sockpath[0] != '/') { 702 error_report("socket path must be absolute"); 703 exit(EXIT_FAILURE); 704 } 705 break; 706 case 'd': 707 disconnect = true; 708 break; 709 case 'c': 710 device = optarg; 711 break; 712 case 'e': 713 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 714 shared < 0) { 715 error_report("Invalid shared device number '%s'", optarg); 716 exit(EXIT_FAILURE); 717 } 718 break; 719 case 'f': 720 fmt = optarg; 721 break; 722 case 't': 723 persistent = 1; 724 break; 725 case 'x': 726 export_name = optarg; 727 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 728 error_report("export name '%s' too long", export_name); 729 exit(EXIT_FAILURE); 730 } 731 break; 732 case 'D': 733 export_description = optarg; 734 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 735 error_report("export description '%s' too long", 736 export_description); 737 exit(EXIT_FAILURE); 738 } 739 break; 740 case 'v': 741 verbose = 1; 742 break; 743 case 'V': 744 version(argv[0]); 745 exit(0); 746 break; 747 case 'h': 748 usage(argv[0]); 749 exit(0); 750 break; 751 case '?': 752 error_report("Try `%s --help' for more information.", argv[0]); 753 exit(EXIT_FAILURE); 754 case QEMU_NBD_OPT_OBJECT: 755 user_creatable_process_cmdline(optarg); 756 break; 757 case QEMU_NBD_OPT_TLSCREDS: 758 tlscredsid = optarg; 759 break; 760 case QEMU_NBD_OPT_TLSHOSTNAME: 761 tlshostname = optarg; 762 break; 763 case QEMU_NBD_OPT_IMAGE_OPTS: 764 imageOpts = true; 765 break; 766 case 'T': 767 trace_opt_parse(optarg); 768 break; 769 case QEMU_NBD_OPT_TLSAUTHZ: 770 tlsauthz = optarg; 771 break; 772 case QEMU_NBD_OPT_FORK: 773 fork_process = true; 774 break; 775 case 'L': 776 list = true; 777 break; 778 case QEMU_NBD_OPT_PID_FILE: 779 pid_file_name = optarg; 780 break; 781 case QEMU_NBD_OPT_SELINUX_LABEL: 782 selinux_label = optarg; 783 break; 784 } 785 } 786 787 if (list) { 788 if (argc != optind) { 789 error_report("List mode is incompatible with a file name"); 790 exit(EXIT_FAILURE); 791 } 792 if (export_name || export_description || dev_offset || 793 device || disconnect || fmt || sn_id_or_name || bitmaps || 794 alloc_depth || seen_aio || seen_discard || seen_cache) { 795 error_report("List mode is incompatible with per-device settings"); 796 exit(EXIT_FAILURE); 797 } 798 if (fork_process) { 799 error_report("List mode is incompatible with forking"); 800 exit(EXIT_FAILURE); 801 } 802 } else if ((argc - optind) != 1) { 803 error_report("Invalid number of arguments"); 804 error_printf("Try `%s --help' for more information.\n", argv[0]); 805 exit(EXIT_FAILURE); 806 } else if (!export_name) { 807 export_name = ""; 808 } 809 810 if (!trace_init_backends()) { 811 exit(1); 812 } 813 trace_init_file(); 814 qemu_set_log(LOG_TRACE, &error_fatal); 815 816 socket_activation = check_socket_activation(); 817 if (socket_activation == 0) { 818 if (!sockpath) { 819 setup_address_and_port(&bindto, &port); 820 } 821 } else { 822 /* Using socket activation - check user didn't use -p etc. */ 823 const char *err_msg = socket_activation_validate_opts(device, sockpath, 824 bindto, port, 825 selinux_label, 826 list); 827 if (err_msg != NULL) { 828 error_report("%s", err_msg); 829 exit(EXIT_FAILURE); 830 } 831 832 /* qemu-nbd can only listen on a single socket. */ 833 if (socket_activation > 1) { 834 error_report("qemu-nbd does not support socket activation with %s > 1", 835 "LISTEN_FDS"); 836 exit(EXIT_FAILURE); 837 } 838 } 839 840 if (tlscredsid) { 841 if (device) { 842 error_report("TLS is not supported with a host device"); 843 exit(EXIT_FAILURE); 844 } 845 if (tlsauthz && list) { 846 error_report("TLS authorization is incompatible with export list"); 847 exit(EXIT_FAILURE); 848 } 849 if (tlshostname && !list) { 850 error_report("TLS hostname is only supported with export list"); 851 exit(EXIT_FAILURE); 852 } 853 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 854 if (local_err) { 855 error_reportf_err(local_err, "Failed to get TLS creds: "); 856 exit(EXIT_FAILURE); 857 } 858 } else { 859 if (tlsauthz) { 860 error_report("--tls-authz is not permitted without --tls-creds"); 861 exit(EXIT_FAILURE); 862 } 863 if (tlshostname) { 864 error_report("--tls-hostname is not permitted without --tls-creds"); 865 exit(EXIT_FAILURE); 866 } 867 } 868 869 if (selinux_label) { 870 #ifdef CONFIG_SELINUX 871 if (sockpath == NULL && device == NULL) { 872 error_report("--selinux-label is not permitted without --socket"); 873 exit(EXIT_FAILURE); 874 } 875 #else 876 error_report("SELinux support not enabled in this binary"); 877 exit(EXIT_FAILURE); 878 #endif 879 } 880 881 if (list) { 882 saddr = nbd_build_socket_address(sockpath, bindto, port); 883 return qemu_nbd_client_list(saddr, tlscreds, 884 tlshostname ? tlshostname : bindto); 885 } 886 887 #if !HAVE_NBD_DEVICE 888 if (disconnect || device) { 889 error_report("Kernel /dev/nbdN support not available"); 890 exit(EXIT_FAILURE); 891 } 892 #else /* HAVE_NBD_DEVICE */ 893 if (disconnect) { 894 int nbdfd = open(argv[optind], O_RDWR); 895 if (nbdfd < 0) { 896 error_report("Cannot open %s: %s", argv[optind], 897 strerror(errno)); 898 exit(EXIT_FAILURE); 899 } 900 nbd_disconnect(nbdfd); 901 902 close(nbdfd); 903 904 printf("%s disconnected\n", argv[optind]); 905 906 return 0; 907 } 908 #endif 909 910 if ((device && !verbose) || fork_process) { 911 #ifndef WIN32 912 g_autoptr(GError) err = NULL; 913 int stderr_fd[2]; 914 pid_t pid; 915 int ret; 916 917 if (!g_unix_open_pipe(stderr_fd, FD_CLOEXEC, &err)) { 918 error_report("Error setting up communication pipe: %s", 919 err->message); 920 exit(EXIT_FAILURE); 921 } 922 923 /* Now daemonize, but keep a communication channel open to 924 * print errors and exit with the proper status code. 925 */ 926 pid = fork(); 927 if (pid < 0) { 928 error_report("Failed to fork: %s", strerror(errno)); 929 exit(EXIT_FAILURE); 930 } else if (pid == 0) { 931 close(stderr_fd[0]); 932 933 /* Remember parent's stderr if we will be restoring it. */ 934 if (fork_process) { 935 old_stderr = dup(STDERR_FILENO); 936 } 937 938 ret = qemu_daemon(1, 0); 939 940 /* Temporarily redirect stderr to the parent's pipe... */ 941 dup2(stderr_fd[1], STDERR_FILENO); 942 if (ret < 0) { 943 error_report("Failed to daemonize: %s", strerror(errno)); 944 exit(EXIT_FAILURE); 945 } 946 947 /* ... close the descriptor we inherited and go on. */ 948 close(stderr_fd[1]); 949 } else { 950 bool errors = false; 951 char *buf; 952 953 /* In the parent. Print error messages from the child until 954 * it closes the pipe. 955 */ 956 close(stderr_fd[1]); 957 buf = g_malloc(1024); 958 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 959 errors = true; 960 ret = qemu_write_full(STDERR_FILENO, buf, ret); 961 if (ret < 0) { 962 exit(EXIT_FAILURE); 963 } 964 } 965 if (ret < 0) { 966 error_report("Cannot read from daemon: %s", 967 strerror(errno)); 968 exit(EXIT_FAILURE); 969 } 970 971 /* Usually the daemon should not print any message. 972 * Exit with zero status in that case. 973 */ 974 exit(errors); 975 } 976 #else /* WIN32 */ 977 error_report("Unable to fork into background on Windows hosts"); 978 exit(EXIT_FAILURE); 979 #endif /* WIN32 */ 980 } 981 982 if (device != NULL && sockpath == NULL) { 983 sockpath = g_malloc(128); 984 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 985 } 986 987 server = qio_net_listener_new(); 988 if (socket_activation == 0) { 989 int backlog; 990 991 if (persistent || shared == 0) { 992 backlog = SOMAXCONN; 993 } else { 994 backlog = MIN(shared, SOMAXCONN); 995 } 996 #ifdef CONFIG_SELINUX 997 if (selinux_label && setsockcreatecon_raw(selinux_label) == -1) { 998 error_report("Cannot set SELinux socket create context to %s: %s", 999 selinux_label, strerror(errno)); 1000 exit(EXIT_FAILURE); 1001 } 1002 #endif 1003 saddr = nbd_build_socket_address(sockpath, bindto, port); 1004 if (qio_net_listener_open_sync(server, saddr, backlog, 1005 &local_err) < 0) { 1006 object_unref(OBJECT(server)); 1007 error_report_err(local_err); 1008 exit(EXIT_FAILURE); 1009 } 1010 #ifdef CONFIG_SELINUX 1011 if (selinux_label && setsockcreatecon_raw(NULL) == -1) { 1012 error_report("Cannot clear SELinux socket create context: %s", 1013 strerror(errno)); 1014 exit(EXIT_FAILURE); 1015 } 1016 #endif 1017 } else { 1018 size_t i; 1019 /* See comment in check_socket_activation above. */ 1020 for (i = 0; i < socket_activation; i++) { 1021 QIOChannelSocket *sioc; 1022 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 1023 &local_err); 1024 if (sioc == NULL) { 1025 object_unref(OBJECT(server)); 1026 error_reportf_err(local_err, 1027 "Failed to use socket activation: "); 1028 exit(EXIT_FAILURE); 1029 } 1030 qio_net_listener_add(server, sioc); 1031 object_unref(OBJECT(sioc)); 1032 } 1033 } 1034 1035 qemu_init_main_loop(&error_fatal); 1036 bdrv_init(); 1037 atexit(qemu_nbd_shutdown); 1038 1039 srcpath = argv[optind]; 1040 if (imageOpts) { 1041 QemuOpts *opts; 1042 if (fmt) { 1043 error_report("--image-opts and -f are mutually exclusive"); 1044 exit(EXIT_FAILURE); 1045 } 1046 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1047 if (!opts) { 1048 qemu_opts_reset(&file_opts); 1049 exit(EXIT_FAILURE); 1050 } 1051 options = qemu_opts_to_qdict(opts, NULL); 1052 qemu_opts_reset(&file_opts); 1053 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1054 } else { 1055 if (fmt) { 1056 options = qdict_new(); 1057 qdict_put_str(options, "driver", fmt); 1058 } 1059 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1060 } 1061 1062 if (!blk) { 1063 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1064 argv[optind]); 1065 exit(EXIT_FAILURE); 1066 } 1067 bs = blk_bs(blk); 1068 1069 if (dev_offset) { 1070 QDict *raw_opts = qdict_new(); 1071 qdict_put_str(raw_opts, "driver", "raw"); 1072 qdict_put_str(raw_opts, "file", bs->node_name); 1073 qdict_put_int(raw_opts, "offset", dev_offset); 1074 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1075 blk_remove_bs(blk); 1076 blk_insert_bs(blk, bs, &error_fatal); 1077 bdrv_unref(bs); 1078 } 1079 1080 blk_set_enable_write_cache(blk, !writethrough); 1081 1082 if (sn_opts) { 1083 ret = bdrv_snapshot_load_tmp(bs, 1084 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1085 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1086 &local_err); 1087 } else if (sn_id_or_name) { 1088 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1089 &local_err); 1090 } 1091 if (ret < 0) { 1092 error_reportf_err(local_err, "Failed to load snapshot: "); 1093 exit(EXIT_FAILURE); 1094 } 1095 1096 bs->detect_zeroes = detect_zeroes; 1097 1098 nbd_server_is_qemu_nbd(shared); 1099 1100 export_opts = g_new(BlockExportOptions, 1); 1101 *export_opts = (BlockExportOptions) { 1102 .type = BLOCK_EXPORT_TYPE_NBD, 1103 .id = g_strdup("qemu-nbd-export"), 1104 .node_name = g_strdup(bdrv_get_node_name(bs)), 1105 .has_writethrough = true, 1106 .writethrough = writethrough, 1107 .has_writable = true, 1108 .writable = !readonly, 1109 .u.nbd = { 1110 .has_name = true, 1111 .name = g_strdup(export_name), 1112 .has_description = !!export_description, 1113 .description = g_strdup(export_description), 1114 .has_bitmaps = !!bitmaps, 1115 .bitmaps = bitmaps, 1116 .has_allocation_depth = alloc_depth, 1117 .allocation_depth = alloc_depth, 1118 }, 1119 }; 1120 blk_exp_add(export_opts, &error_fatal); 1121 qapi_free_BlockExportOptions(export_opts); 1122 1123 if (device) { 1124 #if HAVE_NBD_DEVICE 1125 int ret; 1126 1127 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1128 if (ret != 0) { 1129 error_report("Failed to create client thread: %s", strerror(ret)); 1130 exit(EXIT_FAILURE); 1131 } 1132 #endif 1133 } else { 1134 /* Shut up GCC warnings. */ 1135 memset(&client_thread, 0, sizeof(client_thread)); 1136 } 1137 1138 nbd_update_server_watch(); 1139 1140 if (pid_file_name) { 1141 qemu_write_pidfile(pid_file_name, &error_fatal); 1142 } 1143 1144 /* now when the initialization is (almost) complete, chdir("/") 1145 * to free any busy filesystems */ 1146 if (chdir("/") < 0) { 1147 error_report("Could not chdir to root directory: %s", 1148 strerror(errno)); 1149 exit(EXIT_FAILURE); 1150 } 1151 1152 if (fork_process) { 1153 dup2(old_stderr, STDERR_FILENO); 1154 close(old_stderr); 1155 } 1156 1157 state = RUNNING; 1158 do { 1159 main_loop_wait(false); 1160 if (state == TERMINATE) { 1161 blk_exp_close_all(); 1162 state = TERMINATED; 1163 } 1164 } while (state != TERMINATED); 1165 1166 blk_unref(blk); 1167 if (sockpath) { 1168 unlink(sockpath); 1169 } 1170 1171 qemu_opts_del(sn_opts); 1172 1173 if (device) { 1174 void *ret; 1175 pthread_join(client_thread, &ret); 1176 exit(ret != NULL); 1177 } else { 1178 exit(EXIT_SUCCESS); 1179 } 1180 }