qemu-nbd.c (36131B)
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 70static int verbose; 71static char *srcpath; 72static SocketAddress *saddr; 73static int persistent = 0; 74static enum { RUNNING, TERMINATE, TERMINATED } state; 75static int shared = 1; 76static int nb_fds; 77static QIONetListener *server; 78static QCryptoTLSCreds *tlscreds; 79static const char *tlsauthz; 80 81static 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 used to access the disk image, the\n" 139" valid options are: 'none', 'writeback' (default),\n" 140" 'writethrough', 'directsync' and 'unsafe'\n" 141" --aio=MODE set AIO mode (native, io_uring or threads)\n" 142" --discard=MODE set discard mode (ignore, unmap)\n" 143" --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 144" --image-opts treat FILE as a full set of image options\n" 145"\n" 146QEMU_HELP_BOTTOM "\n" 147 , name, name, NBD_DEFAULT_PORT, "DEVICE"); 148} 149 150static void version(const char *name) 151{ 152 printf( 153"%s " QEMU_FULL_VERSION "\n" 154"Written by Anthony Liguori.\n" 155"\n" 156QEMU_COPYRIGHT "\n" 157"This is free software; see the source for copying conditions. There is NO\n" 158"warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 159 , name); 160} 161 162#ifdef CONFIG_POSIX 163/* 164 * The client thread uses SIGTERM to interrupt the server. A signal 165 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 166 */ 167void qemu_system_killed(int signum, pid_t pid) 168{ 169 qatomic_cmpxchg(&state, RUNNING, TERMINATE); 170 qemu_notify_event(); 171} 172#endif /* CONFIG_POSIX */ 173 174static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, 175 const char *hostname) 176{ 177 int ret = EXIT_FAILURE; 178 int rc; 179 Error *err = NULL; 180 QIOChannelSocket *sioc; 181 NBDExportInfo *list; 182 int i, j; 183 184 sioc = qio_channel_socket_new(); 185 if (qio_channel_socket_connect_sync(sioc, saddr, &err) < 0) { 186 error_report_err(err); 187 goto out; 188 } 189 rc = nbd_receive_export_list(QIO_CHANNEL(sioc), tls, hostname, &list, 190 &err); 191 if (rc < 0) { 192 if (err) { 193 error_report_err(err); 194 } 195 goto out; 196 } 197 printf("exports available: %d\n", rc); 198 for (i = 0; i < rc; i++) { 199 printf(" export: '%s'\n", list[i].name); 200 if (list[i].description && *list[i].description) { 201 printf(" description: %s\n", list[i].description); 202 } 203 if (list[i].flags & NBD_FLAG_HAS_FLAGS) { 204 static const char *const flag_names[] = { 205 [NBD_FLAG_READ_ONLY_BIT] = "readonly", 206 [NBD_FLAG_SEND_FLUSH_BIT] = "flush", 207 [NBD_FLAG_SEND_FUA_BIT] = "fua", 208 [NBD_FLAG_ROTATIONAL_BIT] = "rotational", 209 [NBD_FLAG_SEND_TRIM_BIT] = "trim", 210 [NBD_FLAG_SEND_WRITE_ZEROES_BIT] = "zeroes", 211 [NBD_FLAG_SEND_DF_BIT] = "df", 212 [NBD_FLAG_CAN_MULTI_CONN_BIT] = "multi", 213 [NBD_FLAG_SEND_RESIZE_BIT] = "resize", 214 [NBD_FLAG_SEND_CACHE_BIT] = "cache", 215 [NBD_FLAG_SEND_FAST_ZERO_BIT] = "fast-zero", 216 }; 217 218 printf(" size: %" PRIu64 "\n", list[i].size); 219 printf(" flags: 0x%x (", list[i].flags); 220 for (size_t bit = 0; bit < ARRAY_SIZE(flag_names); bit++) { 221 if (flag_names[bit] && (list[i].flags & (1 << bit))) { 222 printf(" %s", flag_names[bit]); 223 } 224 } 225 printf(" )\n"); 226 } 227 if (list[i].min_block) { 228 printf(" min block: %u\n", list[i].min_block); 229 printf(" opt block: %u\n", list[i].opt_block); 230 printf(" max block: %u\n", list[i].max_block); 231 } 232 if (list[i].n_contexts) { 233 printf(" available meta contexts: %d\n", list[i].n_contexts); 234 for (j = 0; j < list[i].n_contexts; j++) { 235 printf(" %s\n", list[i].contexts[j]); 236 } 237 } 238 } 239 nbd_free_export_list(list, rc); 240 241 ret = EXIT_SUCCESS; 242 out: 243 object_unref(OBJECT(sioc)); 244 return ret; 245} 246 247 248#if HAVE_NBD_DEVICE 249static void *show_parts(void *arg) 250{ 251 char *device = arg; 252 int nbd; 253 254 /* linux just needs an open() to trigger 255 * the partition table update 256 * but remember to load the module with max_part != 0 : 257 * modprobe nbd max_part=63 258 */ 259 nbd = open(device, O_RDWR); 260 if (nbd >= 0) { 261 close(nbd); 262 } 263 return NULL; 264} 265 266static void *nbd_client_thread(void *arg) 267{ 268 char *device = arg; 269 NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; 270 QIOChannelSocket *sioc; 271 int fd = -1; 272 int ret = EXIT_FAILURE; 273 pthread_t show_parts_thread; 274 Error *local_error = NULL; 275 276 sioc = qio_channel_socket_new(); 277 if (qio_channel_socket_connect_sync(sioc, 278 saddr, 279 &local_error) < 0) { 280 error_report_err(local_error); 281 goto out; 282 } 283 284 if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), 285 NULL, NULL, NULL, &info, &local_error) < 0) { 286 if (local_error) { 287 error_report_err(local_error); 288 } 289 goto out; 290 } 291 292 fd = open(device, O_RDWR); 293 if (fd < 0) { 294 /* Linux-only, we can use %m in printf. */ 295 error_report("Failed to open %s: %m", device); 296 goto out; 297 } 298 299 if (nbd_init(fd, sioc, &info, &local_error) < 0) { 300 error_report_err(local_error); 301 goto out; 302 } 303 304 /* update partition table */ 305 pthread_create(&show_parts_thread, NULL, show_parts, device); 306 307 if (verbose) { 308 fprintf(stderr, "NBD device %s is now connected to %s\n", 309 device, srcpath); 310 } else { 311 /* Close stderr so that the qemu-nbd process exits. */ 312 dup2(STDOUT_FILENO, STDERR_FILENO); 313 } 314 315 if (nbd_client(fd) < 0) { 316 goto out; 317 } 318 319 ret = EXIT_SUCCESS; 320 321 out: 322 if (fd >= 0) { 323 close(fd); 324 } 325 object_unref(OBJECT(sioc)); 326 g_free(info.name); 327 kill(getpid(), SIGTERM); 328 return (void *) (intptr_t) ret; 329} 330#endif /* HAVE_NBD_DEVICE */ 331 332static int nbd_can_accept(void) 333{ 334 return state == RUNNING && (shared == 0 || nb_fds < shared); 335} 336 337static void nbd_update_server_watch(void); 338 339static void nbd_client_closed(NBDClient *client, bool negotiated) 340{ 341 nb_fds--; 342 if (negotiated && nb_fds == 0 && !persistent && state == RUNNING) { 343 state = TERMINATE; 344 } 345 nbd_update_server_watch(); 346 nbd_client_put(client); 347} 348 349static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, 350 gpointer opaque) 351{ 352 if (state >= TERMINATE) { 353 return; 354 } 355 356 nb_fds++; 357 nbd_update_server_watch(); 358 nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); 359} 360 361static void nbd_update_server_watch(void) 362{ 363 if (nbd_can_accept()) { 364 qio_net_listener_set_client_func(server, nbd_accept, NULL, NULL); 365 } else { 366 qio_net_listener_set_client_func(server, NULL, NULL, NULL); 367 } 368} 369 370 371static SocketAddress *nbd_build_socket_address(const char *sockpath, 372 const char *bindto, 373 const char *port) 374{ 375 SocketAddress *saddr; 376 377 saddr = g_new0(SocketAddress, 1); 378 if (sockpath) { 379 saddr->type = SOCKET_ADDRESS_TYPE_UNIX; 380 saddr->u.q_unix.path = g_strdup(sockpath); 381 } else { 382 InetSocketAddress *inet; 383 saddr->type = SOCKET_ADDRESS_TYPE_INET; 384 inet = &saddr->u.inet; 385 inet->host = g_strdup(bindto); 386 if (port) { 387 inet->port = g_strdup(port); 388 } else { 389 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 390 } 391 } 392 393 return saddr; 394} 395 396 397static QemuOptsList file_opts = { 398 .name = "file", 399 .implied_opt_name = "file", 400 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 401 .desc = { 402 /* no elements => accept any params */ 403 { /* end of list */ } 404 }, 405}; 406 407static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list, 408 Error **errp) 409{ 410 Object *obj; 411 QCryptoTLSCreds *creds; 412 413 obj = object_resolve_path_component( 414 object_get_objects_root(), id); 415 if (!obj) { 416 error_setg(errp, "No TLS credentials with id '%s'", 417 id); 418 return NULL; 419 } 420 creds = (QCryptoTLSCreds *) 421 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 422 if (!creds) { 423 error_setg(errp, "Object with id '%s' is not TLS credentials", 424 id); 425 return NULL; 426 } 427 428 if (!qcrypto_tls_creds_check_endpoint(creds, 429 list 430 ? QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT 431 : QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, 432 errp)) { 433 return NULL; 434 } 435 object_ref(obj); 436 return creds; 437} 438 439static void setup_address_and_port(const char **address, const char **port) 440{ 441 if (*address == NULL) { 442 *address = "0.0.0.0"; 443 } 444 445 if (*port == NULL) { 446 *port = stringify(NBD_DEFAULT_PORT); 447 } 448} 449 450/* 451 * Check socket parameters compatibility when socket activation is used. 452 */ 453static const char *socket_activation_validate_opts(const char *device, 454 const char *sockpath, 455 const char *address, 456 const char *port, 457 bool list) 458{ 459 if (device != NULL) { 460 return "NBD device can't be set when using socket activation"; 461 } 462 463 if (sockpath != NULL) { 464 return "Unix socket can't be set when using socket activation"; 465 } 466 467 if (address != NULL) { 468 return "The interface can't be set when using socket activation"; 469 } 470 471 if (port != NULL) { 472 return "TCP port number can't be set when using socket activation"; 473 } 474 475 if (list) { 476 return "List mode is incompatible with socket activation"; 477 } 478 479 return NULL; 480} 481 482static void qemu_nbd_shutdown(void) 483{ 484 job_cancel_sync_all(); 485 blk_exp_close_all(); 486 bdrv_close_all(); 487} 488 489int main(int argc, char **argv) 490{ 491 BlockBackend *blk; 492 BlockDriverState *bs; 493 uint64_t dev_offset = 0; 494 bool readonly = false; 495 bool disconnect = false; 496 const char *bindto = NULL; 497 const char *port = NULL; 498 char *sockpath = NULL; 499 char *device = NULL; 500 QemuOpts *sn_opts = NULL; 501 const char *sn_id_or_name = NULL; 502 const char *sopt = "hVb:o:p:rsnc:dvk:e:f:tl:x:T:D:AB:L"; 503 struct option lopt[] = { 504 { "help", no_argument, NULL, 'h' }, 505 { "version", no_argument, NULL, 'V' }, 506 { "bind", required_argument, NULL, 'b' }, 507 { "port", required_argument, NULL, 'p' }, 508 { "socket", required_argument, NULL, 'k' }, 509 { "offset", required_argument, NULL, 'o' }, 510 { "read-only", no_argument, NULL, 'r' }, 511 { "allocation-depth", no_argument, NULL, 'A' }, 512 { "bitmap", required_argument, NULL, 'B' }, 513 { "connect", required_argument, NULL, 'c' }, 514 { "disconnect", no_argument, NULL, 'd' }, 515 { "list", no_argument, NULL, 'L' }, 516 { "snapshot", no_argument, NULL, 's' }, 517 { "load-snapshot", required_argument, NULL, 'l' }, 518 { "nocache", no_argument, NULL, 'n' }, 519 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 520 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 521 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 522 { "detect-zeroes", required_argument, NULL, 523 QEMU_NBD_OPT_DETECT_ZEROES }, 524 { "shared", required_argument, NULL, 'e' }, 525 { "format", required_argument, NULL, 'f' }, 526 { "persistent", no_argument, NULL, 't' }, 527 { "verbose", no_argument, NULL, 'v' }, 528 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 529 { "export-name", required_argument, NULL, 'x' }, 530 { "description", required_argument, NULL, 'D' }, 531 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 532 { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, 533 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 534 { "trace", required_argument, NULL, 'T' }, 535 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 536 { "pid-file", required_argument, NULL, QEMU_NBD_OPT_PID_FILE }, 537 { NULL, 0, NULL, 0 } 538 }; 539 int ch; 540 int opt_ind = 0; 541 int flags = BDRV_O_RDWR; 542 int ret = 0; 543 bool seen_cache = false; 544 bool seen_discard = false; 545 bool seen_aio = false; 546 pthread_t client_thread; 547 const char *fmt = NULL; 548 Error *local_err = NULL; 549 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 550 QDict *options = NULL; 551 const char *export_name = NULL; /* defaults to "" later for server mode */ 552 const char *export_description = NULL; 553 strList *bitmaps = NULL; 554 bool alloc_depth = false; 555 const char *tlscredsid = NULL; 556 bool imageOpts = false; 557 bool writethrough = false; /* Client will flush as needed. */ 558 bool fork_process = false; 559 bool list = false; 560 int old_stderr = -1; 561 unsigned socket_activation; 562 const char *pid_file_name = NULL; 563 BlockExportOptions *export_opts; 564 565#ifdef CONFIG_POSIX 566 os_setup_early_signal_handling(); 567 os_setup_signal_handling(); 568#endif 569 570 socket_init(); 571 error_init(argv[0]); 572 module_call_init(MODULE_INIT_TRACE); 573 qcrypto_init(&error_fatal); 574 575 module_call_init(MODULE_INIT_QOM); 576 qemu_add_opts(&qemu_trace_opts); 577 qemu_init_exec_dir(argv[0]); 578 579 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 580 switch (ch) { 581 case 's': 582 flags |= BDRV_O_SNAPSHOT; 583 break; 584 case 'n': 585 optarg = (char *) "none"; 586 /* fallthrough */ 587 case QEMU_NBD_OPT_CACHE: 588 if (seen_cache) { 589 error_report("-n and --cache can only be specified once"); 590 exit(EXIT_FAILURE); 591 } 592 seen_cache = true; 593 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 594 error_report("Invalid cache mode `%s'", optarg); 595 exit(EXIT_FAILURE); 596 } 597 break; 598 case QEMU_NBD_OPT_AIO: 599 if (seen_aio) { 600 error_report("--aio can only be specified once"); 601 exit(EXIT_FAILURE); 602 } 603 seen_aio = true; 604 if (bdrv_parse_aio(optarg, &flags) < 0) { 605 error_report("Invalid aio mode '%s'", optarg); 606 exit(EXIT_FAILURE); 607 } 608 break; 609 case QEMU_NBD_OPT_DISCARD: 610 if (seen_discard) { 611 error_report("--discard can only be specified once"); 612 exit(EXIT_FAILURE); 613 } 614 seen_discard = true; 615 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 616 error_report("Invalid discard mode `%s'", optarg); 617 exit(EXIT_FAILURE); 618 } 619 break; 620 case QEMU_NBD_OPT_DETECT_ZEROES: 621 detect_zeroes = 622 qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, 623 optarg, 624 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 625 &local_err); 626 if (local_err) { 627 error_reportf_err(local_err, 628 "Failed to parse detect_zeroes mode: "); 629 exit(EXIT_FAILURE); 630 } 631 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 632 !(flags & BDRV_O_UNMAP)) { 633 error_report("setting detect-zeroes to unmap is not allowed " 634 "without setting discard operation to unmap"); 635 exit(EXIT_FAILURE); 636 } 637 break; 638 case 'b': 639 bindto = optarg; 640 break; 641 case 'p': 642 port = optarg; 643 break; 644 case 'o': 645 if (qemu_strtou64(optarg, NULL, 0, &dev_offset) < 0) { 646 error_report("Invalid offset '%s'", optarg); 647 exit(EXIT_FAILURE); 648 } 649 break; 650 case 'l': 651 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 652 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 653 optarg, false); 654 if (!sn_opts) { 655 error_report("Failed in parsing snapshot param `%s'", 656 optarg); 657 exit(EXIT_FAILURE); 658 } 659 } else { 660 sn_id_or_name = optarg; 661 } 662 /* fall through */ 663 case 'r': 664 readonly = true; 665 flags &= ~BDRV_O_RDWR; 666 break; 667 case 'A': 668 alloc_depth = true; 669 break; 670 case 'B': 671 QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg)); 672 break; 673 case 'k': 674 sockpath = optarg; 675 if (sockpath[0] != '/') { 676 error_report("socket path must be absolute"); 677 exit(EXIT_FAILURE); 678 } 679 break; 680 case 'd': 681 disconnect = true; 682 break; 683 case 'c': 684 device = optarg; 685 break; 686 case 'e': 687 if (qemu_strtoi(optarg, NULL, 0, &shared) < 0 || 688 shared < 0) { 689 error_report("Invalid shared device number '%s'", optarg); 690 exit(EXIT_FAILURE); 691 } 692 break; 693 case 'f': 694 fmt = optarg; 695 break; 696 case 't': 697 persistent = 1; 698 break; 699 case 'x': 700 export_name = optarg; 701 if (strlen(export_name) > NBD_MAX_STRING_SIZE) { 702 error_report("export name '%s' too long", export_name); 703 exit(EXIT_FAILURE); 704 } 705 break; 706 case 'D': 707 export_description = optarg; 708 if (strlen(export_description) > NBD_MAX_STRING_SIZE) { 709 error_report("export description '%s' too long", 710 export_description); 711 exit(EXIT_FAILURE); 712 } 713 break; 714 case 'v': 715 verbose = 1; 716 break; 717 case 'V': 718 version(argv[0]); 719 exit(0); 720 break; 721 case 'h': 722 usage(argv[0]); 723 exit(0); 724 break; 725 case '?': 726 error_report("Try `%s --help' for more information.", argv[0]); 727 exit(EXIT_FAILURE); 728 case QEMU_NBD_OPT_OBJECT: 729 user_creatable_process_cmdline(optarg); 730 break; 731 case QEMU_NBD_OPT_TLSCREDS: 732 tlscredsid = optarg; 733 break; 734 case QEMU_NBD_OPT_IMAGE_OPTS: 735 imageOpts = true; 736 break; 737 case 'T': 738 trace_opt_parse(optarg); 739 break; 740 case QEMU_NBD_OPT_TLSAUTHZ: 741 tlsauthz = optarg; 742 break; 743 case QEMU_NBD_OPT_FORK: 744 fork_process = true; 745 break; 746 case 'L': 747 list = true; 748 break; 749 case QEMU_NBD_OPT_PID_FILE: 750 pid_file_name = optarg; 751 break; 752 } 753 } 754 755 if (list) { 756 if (argc != optind) { 757 error_report("List mode is incompatible with a file name"); 758 exit(EXIT_FAILURE); 759 } 760 if (export_name || export_description || dev_offset || 761 device || disconnect || fmt || sn_id_or_name || bitmaps || 762 alloc_depth || seen_aio || seen_discard || seen_cache) { 763 error_report("List mode is incompatible with per-device settings"); 764 exit(EXIT_FAILURE); 765 } 766 if (fork_process) { 767 error_report("List mode is incompatible with forking"); 768 exit(EXIT_FAILURE); 769 } 770 } else if ((argc - optind) != 1) { 771 error_report("Invalid number of arguments"); 772 error_printf("Try `%s --help' for more information.\n", argv[0]); 773 exit(EXIT_FAILURE); 774 } else if (!export_name) { 775 export_name = ""; 776 } 777 778 if (!trace_init_backends()) { 779 exit(1); 780 } 781 trace_init_file(); 782 qemu_set_log(LOG_TRACE); 783 784 socket_activation = check_socket_activation(); 785 if (socket_activation == 0) { 786 setup_address_and_port(&bindto, &port); 787 } else { 788 /* Using socket activation - check user didn't use -p etc. */ 789 const char *err_msg = socket_activation_validate_opts(device, sockpath, 790 bindto, port, 791 list); 792 if (err_msg != NULL) { 793 error_report("%s", err_msg); 794 exit(EXIT_FAILURE); 795 } 796 797 /* qemu-nbd can only listen on a single socket. */ 798 if (socket_activation > 1) { 799 error_report("qemu-nbd does not support socket activation with %s > 1", 800 "LISTEN_FDS"); 801 exit(EXIT_FAILURE); 802 } 803 } 804 805 if (tlscredsid) { 806 if (sockpath) { 807 error_report("TLS is only supported with IPv4/IPv6"); 808 exit(EXIT_FAILURE); 809 } 810 if (device) { 811 error_report("TLS is not supported with a host device"); 812 exit(EXIT_FAILURE); 813 } 814 if (tlsauthz && list) { 815 error_report("TLS authorization is incompatible with export list"); 816 exit(EXIT_FAILURE); 817 } 818 tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); 819 if (local_err) { 820 error_reportf_err(local_err, "Failed to get TLS creds: "); 821 exit(EXIT_FAILURE); 822 } 823 } else { 824 if (tlsauthz) { 825 error_report("--tls-authz is not permitted without --tls-creds"); 826 exit(EXIT_FAILURE); 827 } 828 } 829 830 if (list) { 831 saddr = nbd_build_socket_address(sockpath, bindto, port); 832 return qemu_nbd_client_list(saddr, tlscreds, bindto); 833 } 834 835#if !HAVE_NBD_DEVICE 836 if (disconnect || device) { 837 error_report("Kernel /dev/nbdN support not available"); 838 exit(EXIT_FAILURE); 839 } 840#else /* HAVE_NBD_DEVICE */ 841 if (disconnect) { 842 int nbdfd = open(argv[optind], O_RDWR); 843 if (nbdfd < 0) { 844 error_report("Cannot open %s: %s", argv[optind], 845 strerror(errno)); 846 exit(EXIT_FAILURE); 847 } 848 nbd_disconnect(nbdfd); 849 850 close(nbdfd); 851 852 printf("%s disconnected\n", argv[optind]); 853 854 return 0; 855 } 856#endif 857 858 if ((device && !verbose) || fork_process) { 859#ifndef WIN32 860 int stderr_fd[2]; 861 pid_t pid; 862 int ret; 863 864 if (qemu_pipe(stderr_fd) < 0) { 865 error_report("Error setting up communication pipe: %s", 866 strerror(errno)); 867 exit(EXIT_FAILURE); 868 } 869 870 /* Now daemonize, but keep a communication channel open to 871 * print errors and exit with the proper status code. 872 */ 873 pid = fork(); 874 if (pid < 0) { 875 error_report("Failed to fork: %s", strerror(errno)); 876 exit(EXIT_FAILURE); 877 } else if (pid == 0) { 878 close(stderr_fd[0]); 879 880 /* Remember parent's stderr if we will be restoring it. */ 881 if (fork_process) { 882 old_stderr = dup(STDERR_FILENO); 883 } 884 885 ret = qemu_daemon(1, 0); 886 887 /* Temporarily redirect stderr to the parent's pipe... */ 888 dup2(stderr_fd[1], STDERR_FILENO); 889 if (ret < 0) { 890 error_report("Failed to daemonize: %s", strerror(errno)); 891 exit(EXIT_FAILURE); 892 } 893 894 /* ... close the descriptor we inherited and go on. */ 895 close(stderr_fd[1]); 896 } else { 897 bool errors = false; 898 char *buf; 899 900 /* In the parent. Print error messages from the child until 901 * it closes the pipe. 902 */ 903 close(stderr_fd[1]); 904 buf = g_malloc(1024); 905 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 906 errors = true; 907 ret = qemu_write_full(STDERR_FILENO, buf, ret); 908 if (ret < 0) { 909 exit(EXIT_FAILURE); 910 } 911 } 912 if (ret < 0) { 913 error_report("Cannot read from daemon: %s", 914 strerror(errno)); 915 exit(EXIT_FAILURE); 916 } 917 918 /* Usually the daemon should not print any message. 919 * Exit with zero status in that case. 920 */ 921 exit(errors); 922 } 923#else /* WIN32 */ 924 error_report("Unable to fork into background on Windows hosts"); 925 exit(EXIT_FAILURE); 926#endif /* WIN32 */ 927 } 928 929 if (device != NULL && sockpath == NULL) { 930 sockpath = g_malloc(128); 931 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 932 } 933 934 server = qio_net_listener_new(); 935 if (socket_activation == 0) { 936 int backlog; 937 938 if (persistent || shared == 0) { 939 backlog = SOMAXCONN; 940 } else { 941 backlog = MIN(shared, SOMAXCONN); 942 } 943 saddr = nbd_build_socket_address(sockpath, bindto, port); 944 if (qio_net_listener_open_sync(server, saddr, backlog, 945 &local_err) < 0) { 946 object_unref(OBJECT(server)); 947 error_report_err(local_err); 948 exit(EXIT_FAILURE); 949 } 950 } else { 951 size_t i; 952 /* See comment in check_socket_activation above. */ 953 for (i = 0; i < socket_activation; i++) { 954 QIOChannelSocket *sioc; 955 sioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD + i, 956 &local_err); 957 if (sioc == NULL) { 958 object_unref(OBJECT(server)); 959 error_reportf_err(local_err, 960 "Failed to use socket activation: "); 961 exit(EXIT_FAILURE); 962 } 963 qio_net_listener_add(server, sioc); 964 object_unref(OBJECT(sioc)); 965 } 966 } 967 968 qemu_init_main_loop(&error_fatal); 969 bdrv_init(); 970 atexit(qemu_nbd_shutdown); 971 972 srcpath = argv[optind]; 973 if (imageOpts) { 974 QemuOpts *opts; 975 if (fmt) { 976 error_report("--image-opts and -f are mutually exclusive"); 977 exit(EXIT_FAILURE); 978 } 979 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 980 if (!opts) { 981 qemu_opts_reset(&file_opts); 982 exit(EXIT_FAILURE); 983 } 984 options = qemu_opts_to_qdict(opts, NULL); 985 qemu_opts_reset(&file_opts); 986 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 987 } else { 988 if (fmt) { 989 options = qdict_new(); 990 qdict_put_str(options, "driver", fmt); 991 } 992 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 993 } 994 995 if (!blk) { 996 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 997 argv[optind]); 998 exit(EXIT_FAILURE); 999 } 1000 bs = blk_bs(blk); 1001 1002 if (dev_offset) { 1003 QDict *raw_opts = qdict_new(); 1004 qdict_put_str(raw_opts, "driver", "raw"); 1005 qdict_put_str(raw_opts, "file", bs->node_name); 1006 qdict_put_int(raw_opts, "offset", dev_offset); 1007 bs = bdrv_open(NULL, NULL, raw_opts, flags, &error_fatal); 1008 blk_remove_bs(blk); 1009 blk_insert_bs(blk, bs, &error_fatal); 1010 bdrv_unref(bs); 1011 } 1012 1013 blk_set_enable_write_cache(blk, !writethrough); 1014 1015 if (sn_opts) { 1016 ret = bdrv_snapshot_load_tmp(bs, 1017 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1018 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1019 &local_err); 1020 } else if (sn_id_or_name) { 1021 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1022 &local_err); 1023 } 1024 if (ret < 0) { 1025 error_reportf_err(local_err, "Failed to load snapshot: "); 1026 exit(EXIT_FAILURE); 1027 } 1028 1029 bs->detect_zeroes = detect_zeroes; 1030 1031 nbd_server_is_qemu_nbd(true); 1032 1033 export_opts = g_new(BlockExportOptions, 1); 1034 *export_opts = (BlockExportOptions) { 1035 .type = BLOCK_EXPORT_TYPE_NBD, 1036 .id = g_strdup("qemu-nbd-export"), 1037 .node_name = g_strdup(bdrv_get_node_name(bs)), 1038 .has_writethrough = true, 1039 .writethrough = writethrough, 1040 .has_writable = true, 1041 .writable = !readonly, 1042 .u.nbd = { 1043 .has_name = true, 1044 .name = g_strdup(export_name), 1045 .has_description = !!export_description, 1046 .description = g_strdup(export_description), 1047 .has_bitmaps = !!bitmaps, 1048 .bitmaps = bitmaps, 1049 .has_allocation_depth = alloc_depth, 1050 .allocation_depth = alloc_depth, 1051 }, 1052 }; 1053 blk_exp_add(export_opts, &error_fatal); 1054 qapi_free_BlockExportOptions(export_opts); 1055 1056 if (device) { 1057#if HAVE_NBD_DEVICE 1058 int ret; 1059 1060 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1061 if (ret != 0) { 1062 error_report("Failed to create client thread: %s", strerror(ret)); 1063 exit(EXIT_FAILURE); 1064 } 1065#endif 1066 } else { 1067 /* Shut up GCC warnings. */ 1068 memset(&client_thread, 0, sizeof(client_thread)); 1069 } 1070 1071 nbd_update_server_watch(); 1072 1073 if (pid_file_name) { 1074 qemu_write_pidfile(pid_file_name, &error_fatal); 1075 } 1076 1077 /* now when the initialization is (almost) complete, chdir("/") 1078 * to free any busy filesystems */ 1079 if (chdir("/") < 0) { 1080 error_report("Could not chdir to root directory: %s", 1081 strerror(errno)); 1082 exit(EXIT_FAILURE); 1083 } 1084 1085 if (fork_process) { 1086 dup2(old_stderr, STDERR_FILENO); 1087 close(old_stderr); 1088 } 1089 1090 state = RUNNING; 1091 do { 1092 main_loop_wait(false); 1093 if (state == TERMINATE) { 1094 blk_exp_close_all(); 1095 state = TERMINATED; 1096 } 1097 } while (state != TERMINATED); 1098 1099 blk_unref(blk); 1100 if (sockpath) { 1101 unlink(sockpath); 1102 } 1103 1104 qemu_opts_del(sn_opts); 1105 1106 if (device) { 1107 void *ret; 1108 pthread_join(client_thread, &ret); 1109 exit(ret != NULL); 1110 } else { 1111 exit(EXIT_SUCCESS); 1112 } 1113}