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 "qapi/error.h" 21 #include "qemu-common.h" 22 #include "qemu/cutils.h" 23 #include "sysemu/block-backend.h" 24 #include "block/block_int.h" 25 #include "block/nbd.h" 26 #include "qemu/main-loop.h" 27 #include "qemu/error-report.h" 28 #include "qemu/config-file.h" 29 #include "qemu/bswap.h" 30 #include "qemu/log.h" 31 #include "block/snapshot.h" 32 #include "qapi/util.h" 33 #include "qapi/qmp/qstring.h" 34 #include "qom/object_interfaces.h" 35 #include "io/channel-socket.h" 36 #include "crypto/init.h" 37 #include "trace/control.h" 38 39 #include <getopt.h> 40 #include <libgen.h> 41 #include <pthread.h> 42 43 #define SOCKET_PATH "/var/lock/qemu-nbd-%s" 44 #define QEMU_NBD_OPT_CACHE 256 45 #define QEMU_NBD_OPT_AIO 257 46 #define QEMU_NBD_OPT_DISCARD 258 47 #define QEMU_NBD_OPT_DETECT_ZEROES 259 48 #define QEMU_NBD_OPT_OBJECT 260 49 #define QEMU_NBD_OPT_TLSCREDS 261 50 #define QEMU_NBD_OPT_IMAGE_OPTS 262 51 #define QEMU_NBD_OPT_FORK 263 52 53 #define MBR_SIZE 512 54 55 static NBDExport *exp; 56 static bool newproto; 57 static int verbose; 58 static char *srcpath; 59 static SocketAddress *saddr; 60 static int persistent = 0; 61 static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; 62 static int shared = 1; 63 static int nb_fds; 64 static QIOChannelSocket *server_ioc; 65 static int server_watch = -1; 66 static QCryptoTLSCreds *tlscreds; 67 68 static void usage(const char *name) 69 { 70 (printf) ( 71 "Usage: %s [OPTIONS] FILE\n" 72 "QEMU Disk Network Block Device Server\n" 73 "\n" 74 " -h, --help display this help and exit\n" 75 " -V, --version output version information and exit\n" 76 "\n" 77 "Connection properties:\n" 78 " -p, --port=PORT port to listen on (default `%d')\n" 79 " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" 80 " -k, --socket=PATH path to the unix socket\n" 81 " (default '"SOCKET_PATH"')\n" 82 " -e, --shared=NUM device can be shared by NUM clients (default '1')\n" 83 " -t, --persistent don't exit on the last connection\n" 84 " -v, --verbose display extra debugging information\n" 85 " -x, --export-name=NAME expose export by name\n" 86 " -D, --description=TEXT with -x, also export a human-readable description\n" 87 "\n" 88 "Exposing part of the image:\n" 89 " -o, --offset=OFFSET offset into the image\n" 90 " -P, --partition=NUM only expose partition NUM\n" 91 "\n" 92 "General purpose options:\n" 93 " --object type,id=ID,... define an object such as 'secret' for providing\n" 94 " passwords and/or encryption keys\n" 95 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 96 " specify tracing options\n" 97 " --fork fork off the server process and exit the parent\n" 98 " once the server is running\n" 99 #ifdef __linux__ 100 "Kernel NBD client support:\n" 101 " -c, --connect=DEV connect FILE to the local NBD device DEV\n" 102 " -d, --disconnect disconnect the specified device\n" 103 "\n" 104 #endif 105 "\n" 106 "Block device options:\n" 107 " -f, --format=FORMAT set image format (raw, qcow2, ...)\n" 108 " -r, --read-only export read-only\n" 109 " -s, --snapshot use FILE as an external snapshot, create a temporary\n" 110 " file with backing_file=FILE, redirect the write to\n" 111 " the temporary one\n" 112 " -l, --load-snapshot=SNAPSHOT_PARAM\n" 113 " load an internal snapshot inside FILE and export it\n" 114 " as an read-only device, SNAPSHOT_PARAM format is\n" 115 " 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" 116 " '[ID_OR_NAME]'\n" 117 " -n, --nocache disable host cache\n" 118 " --cache=MODE set cache mode (none, writeback, ...)\n" 119 " --aio=MODE set AIO mode (native or threads)\n" 120 " --discard=MODE set discard mode (ignore, unmap)\n" 121 " --detect-zeroes=MODE set detect-zeroes mode (off, on, unmap)\n" 122 " --image-opts treat FILE as a full set of image options\n" 123 "\n" 124 "Report bugs to <qemu-devel@nongnu.org>\n" 125 , name, NBD_DEFAULT_PORT, "DEVICE"); 126 } 127 128 static void version(const char *name) 129 { 130 printf( 131 "%s version 0.0.1\n" 132 "Written by Anthony Liguori.\n" 133 "\n" 134 "Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n" 135 "This is free software; see the source for copying conditions. There is NO\n" 136 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" 137 , name); 138 } 139 140 struct partition_record 141 { 142 uint8_t bootable; 143 uint8_t start_head; 144 uint32_t start_cylinder; 145 uint8_t start_sector; 146 uint8_t system; 147 uint8_t end_head; 148 uint8_t end_cylinder; 149 uint8_t end_sector; 150 uint32_t start_sector_abs; 151 uint32_t nb_sectors_abs; 152 }; 153 154 static void read_partition(uint8_t *p, struct partition_record *r) 155 { 156 r->bootable = p[0]; 157 r->start_head = p[1]; 158 r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); 159 r->start_sector = p[2] & 0x3f; 160 r->system = p[4]; 161 r->end_head = p[5]; 162 r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); 163 r->end_sector = p[6] & 0x3f; 164 165 r->start_sector_abs = ldl_le_p(p + 8); 166 r->nb_sectors_abs = ldl_le_p(p + 12); 167 } 168 169 static int find_partition(BlockBackend *blk, int partition, 170 off_t *offset, off_t *size) 171 { 172 struct partition_record mbr[4]; 173 uint8_t data[MBR_SIZE]; 174 int i; 175 int ext_partnum = 4; 176 int ret; 177 178 ret = blk_pread(blk, 0, data, sizeof(data)); 179 if (ret < 0) { 180 error_report("error while reading: %s", strerror(-ret)); 181 exit(EXIT_FAILURE); 182 } 183 184 if (data[510] != 0x55 || data[511] != 0xaa) { 185 return -EINVAL; 186 } 187 188 for (i = 0; i < 4; i++) { 189 read_partition(&data[446 + 16 * i], &mbr[i]); 190 191 if (!mbr[i].system || !mbr[i].nb_sectors_abs) { 192 continue; 193 } 194 195 if (mbr[i].system == 0xF || mbr[i].system == 0x5) { 196 struct partition_record ext[4]; 197 uint8_t data1[MBR_SIZE]; 198 int j; 199 200 ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, 201 data1, sizeof(data1)); 202 if (ret < 0) { 203 error_report("error while reading: %s", strerror(-ret)); 204 exit(EXIT_FAILURE); 205 } 206 207 for (j = 0; j < 4; j++) { 208 read_partition(&data1[446 + 16 * j], &ext[j]); 209 if (!ext[j].system || !ext[j].nb_sectors_abs) { 210 continue; 211 } 212 213 if ((ext_partnum + j + 1) == partition) { 214 *offset = (uint64_t)ext[j].start_sector_abs << 9; 215 *size = (uint64_t)ext[j].nb_sectors_abs << 9; 216 return 0; 217 } 218 } 219 ext_partnum += 4; 220 } else if ((i + 1) == partition) { 221 *offset = (uint64_t)mbr[i].start_sector_abs << 9; 222 *size = (uint64_t)mbr[i].nb_sectors_abs << 9; 223 return 0; 224 } 225 } 226 227 return -ENOENT; 228 } 229 230 static void termsig_handler(int signum) 231 { 232 atomic_cmpxchg(&state, RUNNING, TERMINATE); 233 qemu_notify_event(); 234 } 235 236 237 static void *show_parts(void *arg) 238 { 239 char *device = arg; 240 int nbd; 241 242 /* linux just needs an open() to trigger 243 * the partition table update 244 * but remember to load the module with max_part != 0 : 245 * modprobe nbd max_part=63 246 */ 247 nbd = open(device, O_RDWR); 248 if (nbd >= 0) { 249 close(nbd); 250 } 251 return NULL; 252 } 253 254 static void *nbd_client_thread(void *arg) 255 { 256 char *device = arg; 257 off_t size; 258 uint16_t nbdflags; 259 QIOChannelSocket *sioc; 260 int fd; 261 int ret; 262 pthread_t show_parts_thread; 263 Error *local_error = NULL; 264 265 sioc = qio_channel_socket_new(); 266 if (qio_channel_socket_connect_sync(sioc, 267 saddr, 268 &local_error) < 0) { 269 error_report_err(local_error); 270 goto out; 271 } 272 273 ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), NULL, &nbdflags, 274 NULL, NULL, NULL, 275 &size, &local_error); 276 if (ret < 0) { 277 if (local_error) { 278 error_report_err(local_error); 279 } 280 goto out_socket; 281 } 282 283 fd = open(device, O_RDWR); 284 if (fd < 0) { 285 /* Linux-only, we can use %m in printf. */ 286 error_report("Failed to open %s: %m", device); 287 goto out_socket; 288 } 289 290 ret = nbd_init(fd, sioc, nbdflags, size); 291 if (ret < 0) { 292 goto out_fd; 293 } 294 295 /* update partition table */ 296 pthread_create(&show_parts_thread, NULL, show_parts, device); 297 298 if (verbose) { 299 fprintf(stderr, "NBD device %s is now connected to %s\n", 300 device, srcpath); 301 } else { 302 /* Close stderr so that the qemu-nbd process exits. */ 303 dup2(STDOUT_FILENO, STDERR_FILENO); 304 } 305 306 ret = nbd_client(fd); 307 if (ret) { 308 goto out_fd; 309 } 310 close(fd); 311 object_unref(OBJECT(sioc)); 312 kill(getpid(), SIGTERM); 313 return (void *) EXIT_SUCCESS; 314 315 out_fd: 316 close(fd); 317 out_socket: 318 object_unref(OBJECT(sioc)); 319 out: 320 kill(getpid(), SIGTERM); 321 return (void *) EXIT_FAILURE; 322 } 323 324 static int nbd_can_accept(void) 325 { 326 return nb_fds < shared; 327 } 328 329 static void nbd_export_closed(NBDExport *exp) 330 { 331 assert(state == TERMINATING); 332 state = TERMINATED; 333 } 334 335 static void nbd_update_server_watch(void); 336 337 static void nbd_client_closed(NBDClient *client) 338 { 339 nb_fds--; 340 if (nb_fds == 0 && !persistent && state == RUNNING) { 341 state = TERMINATE; 342 } 343 nbd_update_server_watch(); 344 nbd_client_put(client); 345 } 346 347 static gboolean nbd_accept(QIOChannel *ioc, GIOCondition cond, gpointer opaque) 348 { 349 QIOChannelSocket *cioc; 350 351 cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc), 352 NULL); 353 if (!cioc) { 354 return TRUE; 355 } 356 357 if (state >= TERMINATE) { 358 object_unref(OBJECT(cioc)); 359 return TRUE; 360 } 361 362 nb_fds++; 363 nbd_update_server_watch(); 364 nbd_client_new(newproto ? NULL : exp, cioc, 365 tlscreds, NULL, nbd_client_closed); 366 object_unref(OBJECT(cioc)); 367 368 return TRUE; 369 } 370 371 static void nbd_update_server_watch(void) 372 { 373 if (nbd_can_accept()) { 374 if (server_watch == -1) { 375 server_watch = qio_channel_add_watch(QIO_CHANNEL(server_ioc), 376 G_IO_IN, 377 nbd_accept, 378 NULL, NULL); 379 } 380 } else { 381 if (server_watch != -1) { 382 g_source_remove(server_watch); 383 server_watch = -1; 384 } 385 } 386 } 387 388 389 static SocketAddress *nbd_build_socket_address(const char *sockpath, 390 const char *bindto, 391 const char *port) 392 { 393 SocketAddress *saddr; 394 395 saddr = g_new0(SocketAddress, 1); 396 if (sockpath) { 397 saddr->type = SOCKET_ADDRESS_KIND_UNIX; 398 saddr->u.q_unix.data = g_new0(UnixSocketAddress, 1); 399 saddr->u.q_unix.data->path = g_strdup(sockpath); 400 } else { 401 InetSocketAddress *inet; 402 saddr->type = SOCKET_ADDRESS_KIND_INET; 403 inet = saddr->u.inet.data = g_new0(InetSocketAddress, 1); 404 inet->host = g_strdup(bindto); 405 if (port) { 406 inet->port = g_strdup(port); 407 } else { 408 inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); 409 } 410 } 411 412 return saddr; 413 } 414 415 416 static QemuOptsList file_opts = { 417 .name = "file", 418 .implied_opt_name = "file", 419 .head = QTAILQ_HEAD_INITIALIZER(file_opts.head), 420 .desc = { 421 /* no elements => accept any params */ 422 { /* end of list */ } 423 }, 424 }; 425 426 static QemuOptsList qemu_object_opts = { 427 .name = "object", 428 .implied_opt_name = "qom-type", 429 .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head), 430 .desc = { 431 { } 432 }, 433 }; 434 435 436 437 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) 438 { 439 Object *obj; 440 QCryptoTLSCreds *creds; 441 442 obj = object_resolve_path_component( 443 object_get_objects_root(), id); 444 if (!obj) { 445 error_setg(errp, "No TLS credentials with id '%s'", 446 id); 447 return NULL; 448 } 449 creds = (QCryptoTLSCreds *) 450 object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); 451 if (!creds) { 452 error_setg(errp, "Object with id '%s' is not TLS credentials", 453 id); 454 return NULL; 455 } 456 457 if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { 458 error_setg(errp, 459 "Expecting TLS credentials with a server endpoint"); 460 return NULL; 461 } 462 object_ref(obj); 463 return creds; 464 } 465 466 static void setup_address_and_port(const char **address, const char **port) 467 { 468 if (*address == NULL) { 469 *address = "0.0.0.0"; 470 } 471 472 if (*port == NULL) { 473 *port = stringify(NBD_DEFAULT_PORT); 474 } 475 } 476 477 #define FIRST_SOCKET_ACTIVATION_FD 3 /* defined by systemd ABI */ 478 479 #ifndef _WIN32 480 /* 481 * Check if socket activation was requested via use of the 482 * LISTEN_FDS and LISTEN_PID environment variables. 483 * 484 * Returns 0 if no socket activation, or the number of FDs. 485 */ 486 static unsigned int check_socket_activation(void) 487 { 488 const char *s; 489 unsigned long pid; 490 unsigned long nr_fds; 491 unsigned int i; 492 int fd; 493 int err; 494 495 s = getenv("LISTEN_PID"); 496 if (s == NULL) { 497 return 0; 498 } 499 err = qemu_strtoul(s, NULL, 10, &pid); 500 if (err) { 501 if (verbose) { 502 fprintf(stderr, "malformed %s environment variable (ignored)\n", 503 "LISTEN_PID"); 504 } 505 return 0; 506 } 507 if (pid != getpid()) { 508 if (verbose) { 509 fprintf(stderr, "%s was not for us (ignored)\n", 510 "LISTEN_PID"); 511 } 512 return 0; 513 } 514 515 s = getenv("LISTEN_FDS"); 516 if (s == NULL) { 517 return 0; 518 } 519 err = qemu_strtoul(s, NULL, 10, &nr_fds); 520 if (err) { 521 if (verbose) { 522 fprintf(stderr, "malformed %s environment variable (ignored)\n", 523 "LISTEN_FDS"); 524 } 525 return 0; 526 } 527 assert(nr_fds <= UINT_MAX); 528 529 /* A limitation of current qemu-nbd is that it can only listen on 530 * a single socket. When that limitation is lifted, we can change 531 * this function to allow LISTEN_FDS > 1, and remove the assertion 532 * in the main function below. 533 */ 534 if (nr_fds > 1) { 535 error_report("qemu-nbd does not support socket activation with %s > 1", 536 "LISTEN_FDS"); 537 exit(EXIT_FAILURE); 538 } 539 540 /* So these are not passed to any child processes we might start. */ 541 unsetenv("LISTEN_FDS"); 542 unsetenv("LISTEN_PID"); 543 544 /* So the file descriptors don't leak into child processes. */ 545 for (i = 0; i < nr_fds; ++i) { 546 fd = FIRST_SOCKET_ACTIVATION_FD + i; 547 if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1) { 548 /* If we cannot set FD_CLOEXEC then it probably means the file 549 * descriptor is invalid, so socket activation has gone wrong 550 * and we should exit. 551 */ 552 error_report("Socket activation failed: " 553 "invalid file descriptor fd = %d: %m", 554 fd); 555 exit(EXIT_FAILURE); 556 } 557 } 558 559 return (unsigned int) nr_fds; 560 } 561 562 #else /* !_WIN32 */ 563 static unsigned int check_socket_activation(void) 564 { 565 return 0; 566 } 567 #endif 568 569 /* 570 * Check socket parameters compatibility when socket activation is used. 571 */ 572 static const char *socket_activation_validate_opts(const char *device, 573 const char *sockpath, 574 const char *address, 575 const char *port) 576 { 577 if (device != NULL) { 578 return "NBD device can't be set when using socket activation"; 579 } 580 581 if (sockpath != NULL) { 582 return "Unix socket can't be set when using socket activation"; 583 } 584 585 if (address != NULL) { 586 return "The interface can't be set when using socket activation"; 587 } 588 589 if (port != NULL) { 590 return "TCP port number can't be set when using socket activation"; 591 } 592 593 return NULL; 594 } 595 596 int main(int argc, char **argv) 597 { 598 BlockBackend *blk; 599 BlockDriverState *bs; 600 off_t dev_offset = 0; 601 uint16_t nbdflags = 0; 602 bool disconnect = false; 603 const char *bindto = NULL; 604 const char *port = NULL; 605 char *sockpath = NULL; 606 char *device = NULL; 607 off_t fd_size; 608 QemuOpts *sn_opts = NULL; 609 const char *sn_id_or_name = NULL; 610 const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; 611 struct option lopt[] = { 612 { "help", no_argument, NULL, 'h' }, 613 { "version", no_argument, NULL, 'V' }, 614 { "bind", required_argument, NULL, 'b' }, 615 { "port", required_argument, NULL, 'p' }, 616 { "socket", required_argument, NULL, 'k' }, 617 { "offset", required_argument, NULL, 'o' }, 618 { "read-only", no_argument, NULL, 'r' }, 619 { "partition", required_argument, NULL, 'P' }, 620 { "connect", required_argument, NULL, 'c' }, 621 { "disconnect", no_argument, NULL, 'd' }, 622 { "snapshot", no_argument, NULL, 's' }, 623 { "load-snapshot", required_argument, NULL, 'l' }, 624 { "nocache", no_argument, NULL, 'n' }, 625 { "cache", required_argument, NULL, QEMU_NBD_OPT_CACHE }, 626 { "aio", required_argument, NULL, QEMU_NBD_OPT_AIO }, 627 { "discard", required_argument, NULL, QEMU_NBD_OPT_DISCARD }, 628 { "detect-zeroes", required_argument, NULL, 629 QEMU_NBD_OPT_DETECT_ZEROES }, 630 { "shared", required_argument, NULL, 'e' }, 631 { "format", required_argument, NULL, 'f' }, 632 { "persistent", no_argument, NULL, 't' }, 633 { "verbose", no_argument, NULL, 'v' }, 634 { "object", required_argument, NULL, QEMU_NBD_OPT_OBJECT }, 635 { "export-name", required_argument, NULL, 'x' }, 636 { "description", required_argument, NULL, 'D' }, 637 { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, 638 { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, 639 { "trace", required_argument, NULL, 'T' }, 640 { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, 641 { NULL, 0, NULL, 0 } 642 }; 643 int ch; 644 int opt_ind = 0; 645 char *end; 646 int flags = BDRV_O_RDWR; 647 int partition = -1; 648 int ret = 0; 649 bool seen_cache = false; 650 bool seen_discard = false; 651 bool seen_aio = false; 652 pthread_t client_thread; 653 const char *fmt = NULL; 654 Error *local_err = NULL; 655 BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF; 656 QDict *options = NULL; 657 const char *export_name = NULL; 658 const char *export_description = NULL; 659 const char *tlscredsid = NULL; 660 bool imageOpts = false; 661 bool writethrough = true; 662 char *trace_file = NULL; 663 bool fork_process = false; 664 int old_stderr = -1; 665 unsigned socket_activation; 666 667 /* The client thread uses SIGTERM to interrupt the server. A signal 668 * handler ensures that "qemu-nbd -v -c" exits with a nice status code. 669 */ 670 struct sigaction sa_sigterm; 671 memset(&sa_sigterm, 0, sizeof(sa_sigterm)); 672 sa_sigterm.sa_handler = termsig_handler; 673 sigaction(SIGTERM, &sa_sigterm, NULL); 674 675 module_call_init(MODULE_INIT_TRACE); 676 qcrypto_init(&error_fatal); 677 678 module_call_init(MODULE_INIT_QOM); 679 qemu_add_opts(&qemu_object_opts); 680 qemu_add_opts(&qemu_trace_opts); 681 qemu_init_exec_dir(argv[0]); 682 683 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { 684 switch (ch) { 685 case 's': 686 flags |= BDRV_O_SNAPSHOT; 687 break; 688 case 'n': 689 optarg = (char *) "none"; 690 /* fallthrough */ 691 case QEMU_NBD_OPT_CACHE: 692 if (seen_cache) { 693 error_report("-n and --cache can only be specified once"); 694 exit(EXIT_FAILURE); 695 } 696 seen_cache = true; 697 if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) == -1) { 698 error_report("Invalid cache mode `%s'", optarg); 699 exit(EXIT_FAILURE); 700 } 701 break; 702 case QEMU_NBD_OPT_AIO: 703 if (seen_aio) { 704 error_report("--aio can only be specified once"); 705 exit(EXIT_FAILURE); 706 } 707 seen_aio = true; 708 if (!strcmp(optarg, "native")) { 709 flags |= BDRV_O_NATIVE_AIO; 710 } else if (!strcmp(optarg, "threads")) { 711 /* this is the default */ 712 } else { 713 error_report("invalid aio mode `%s'", optarg); 714 exit(EXIT_FAILURE); 715 } 716 break; 717 case QEMU_NBD_OPT_DISCARD: 718 if (seen_discard) { 719 error_report("--discard can only be specified once"); 720 exit(EXIT_FAILURE); 721 } 722 seen_discard = true; 723 if (bdrv_parse_discard_flags(optarg, &flags) == -1) { 724 error_report("Invalid discard mode `%s'", optarg); 725 exit(EXIT_FAILURE); 726 } 727 break; 728 case QEMU_NBD_OPT_DETECT_ZEROES: 729 detect_zeroes = 730 qapi_enum_parse(BlockdevDetectZeroesOptions_lookup, 731 optarg, 732 BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX, 733 BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, 734 &local_err); 735 if (local_err) { 736 error_reportf_err(local_err, 737 "Failed to parse detect_zeroes mode: "); 738 exit(EXIT_FAILURE); 739 } 740 if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && 741 !(flags & BDRV_O_UNMAP)) { 742 error_report("setting detect-zeroes to unmap is not allowed " 743 "without setting discard operation to unmap"); 744 exit(EXIT_FAILURE); 745 } 746 break; 747 case 'b': 748 bindto = optarg; 749 break; 750 case 'p': 751 port = optarg; 752 break; 753 case 'o': 754 dev_offset = strtoll (optarg, &end, 0); 755 if (*end) { 756 error_report("Invalid offset `%s'", optarg); 757 exit(EXIT_FAILURE); 758 } 759 if (dev_offset < 0) { 760 error_report("Offset must be positive `%s'", optarg); 761 exit(EXIT_FAILURE); 762 } 763 break; 764 case 'l': 765 if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { 766 sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts, 767 optarg, false); 768 if (!sn_opts) { 769 error_report("Failed in parsing snapshot param `%s'", 770 optarg); 771 exit(EXIT_FAILURE); 772 } 773 } else { 774 sn_id_or_name = optarg; 775 } 776 /* fall through */ 777 case 'r': 778 nbdflags |= NBD_FLAG_READ_ONLY; 779 flags &= ~BDRV_O_RDWR; 780 break; 781 case 'P': 782 partition = strtol(optarg, &end, 0); 783 if (*end) { 784 error_report("Invalid partition `%s'", optarg); 785 exit(EXIT_FAILURE); 786 } 787 if (partition < 1 || partition > 8) { 788 error_report("Invalid partition %d", partition); 789 exit(EXIT_FAILURE); 790 } 791 break; 792 case 'k': 793 sockpath = optarg; 794 if (sockpath[0] != '/') { 795 error_report("socket path must be absolute"); 796 exit(EXIT_FAILURE); 797 } 798 break; 799 case 'd': 800 disconnect = true; 801 break; 802 case 'c': 803 device = optarg; 804 break; 805 case 'e': 806 shared = strtol(optarg, &end, 0); 807 if (*end) { 808 error_report("Invalid shared device number '%s'", optarg); 809 exit(EXIT_FAILURE); 810 } 811 if (shared < 1) { 812 error_report("Shared device number must be greater than 0"); 813 exit(EXIT_FAILURE); 814 } 815 break; 816 case 'f': 817 fmt = optarg; 818 break; 819 case 't': 820 persistent = 1; 821 break; 822 case 'x': 823 export_name = optarg; 824 break; 825 case 'D': 826 export_description = optarg; 827 break; 828 case 'v': 829 verbose = 1; 830 break; 831 case 'V': 832 version(argv[0]); 833 exit(0); 834 break; 835 case 'h': 836 usage(argv[0]); 837 exit(0); 838 break; 839 case '?': 840 error_report("Try `%s --help' for more information.", argv[0]); 841 exit(EXIT_FAILURE); 842 case QEMU_NBD_OPT_OBJECT: { 843 QemuOpts *opts; 844 opts = qemu_opts_parse_noisily(&qemu_object_opts, 845 optarg, true); 846 if (!opts) { 847 exit(EXIT_FAILURE); 848 } 849 } break; 850 case QEMU_NBD_OPT_TLSCREDS: 851 tlscredsid = optarg; 852 break; 853 case QEMU_NBD_OPT_IMAGE_OPTS: 854 imageOpts = true; 855 break; 856 case 'T': 857 g_free(trace_file); 858 trace_file = trace_opt_parse(optarg); 859 break; 860 case QEMU_NBD_OPT_FORK: 861 fork_process = true; 862 break; 863 } 864 } 865 866 if ((argc - optind) != 1) { 867 error_report("Invalid number of arguments"); 868 error_printf("Try `%s --help' for more information.\n", argv[0]); 869 exit(EXIT_FAILURE); 870 } 871 872 if (qemu_opts_foreach(&qemu_object_opts, 873 user_creatable_add_opts_foreach, 874 NULL, NULL)) { 875 exit(EXIT_FAILURE); 876 } 877 878 if (!trace_init_backends()) { 879 exit(1); 880 } 881 trace_init_file(trace_file); 882 qemu_set_log(LOG_TRACE); 883 884 socket_activation = check_socket_activation(); 885 if (socket_activation == 0) { 886 setup_address_and_port(&bindto, &port); 887 } else { 888 /* Using socket activation - check user didn't use -p etc. */ 889 const char *err_msg = socket_activation_validate_opts(device, sockpath, 890 bindto, port); 891 if (err_msg != NULL) { 892 error_report("%s", err_msg); 893 exit(EXIT_FAILURE); 894 } 895 } 896 897 if (tlscredsid) { 898 if (sockpath) { 899 error_report("TLS is only supported with IPv4/IPv6"); 900 exit(EXIT_FAILURE); 901 } 902 if (device) { 903 error_report("TLS is not supported with a host device"); 904 exit(EXIT_FAILURE); 905 } 906 if (!export_name) { 907 /* Set the default NBD protocol export name, since 908 * we *must* use new style protocol for TLS */ 909 export_name = ""; 910 } 911 tlscreds = nbd_get_tls_creds(tlscredsid, &local_err); 912 if (local_err) { 913 error_report("Failed to get TLS creds %s", 914 error_get_pretty(local_err)); 915 exit(EXIT_FAILURE); 916 } 917 } 918 919 if (disconnect) { 920 int nbdfd = open(argv[optind], O_RDWR); 921 if (nbdfd < 0) { 922 error_report("Cannot open %s: %s", argv[optind], 923 strerror(errno)); 924 exit(EXIT_FAILURE); 925 } 926 nbd_disconnect(nbdfd); 927 928 close(nbdfd); 929 930 printf("%s disconnected\n", argv[optind]); 931 932 return 0; 933 } 934 935 if ((device && !verbose) || fork_process) { 936 int stderr_fd[2]; 937 pid_t pid; 938 int ret; 939 940 if (qemu_pipe(stderr_fd) < 0) { 941 error_report("Error setting up communication pipe: %s", 942 strerror(errno)); 943 exit(EXIT_FAILURE); 944 } 945 946 /* Now daemonize, but keep a communication channel open to 947 * print errors and exit with the proper status code. 948 */ 949 pid = fork(); 950 if (pid < 0) { 951 error_report("Failed to fork: %s", strerror(errno)); 952 exit(EXIT_FAILURE); 953 } else if (pid == 0) { 954 close(stderr_fd[0]); 955 ret = qemu_daemon(1, 0); 956 957 /* Temporarily redirect stderr to the parent's pipe... */ 958 old_stderr = dup(STDERR_FILENO); 959 dup2(stderr_fd[1], STDERR_FILENO); 960 if (ret < 0) { 961 error_report("Failed to daemonize: %s", strerror(errno)); 962 exit(EXIT_FAILURE); 963 } 964 965 /* ... close the descriptor we inherited and go on. */ 966 close(stderr_fd[1]); 967 } else { 968 bool errors = false; 969 char *buf; 970 971 /* In the parent. Print error messages from the child until 972 * it closes the pipe. 973 */ 974 close(stderr_fd[1]); 975 buf = g_malloc(1024); 976 while ((ret = read(stderr_fd[0], buf, 1024)) > 0) { 977 errors = true; 978 ret = qemu_write_full(STDERR_FILENO, buf, ret); 979 if (ret < 0) { 980 exit(EXIT_FAILURE); 981 } 982 } 983 if (ret < 0) { 984 error_report("Cannot read from daemon: %s", 985 strerror(errno)); 986 exit(EXIT_FAILURE); 987 } 988 989 /* Usually the daemon should not print any message. 990 * Exit with zero status in that case. 991 */ 992 exit(errors); 993 } 994 } 995 996 if (device != NULL && sockpath == NULL) { 997 sockpath = g_malloc(128); 998 snprintf(sockpath, 128, SOCKET_PATH, basename(device)); 999 } 1000 1001 if (socket_activation == 0) { 1002 server_ioc = qio_channel_socket_new(); 1003 saddr = nbd_build_socket_address(sockpath, bindto, port); 1004 if (qio_channel_socket_listen_sync(server_ioc, saddr, &local_err) < 0) { 1005 object_unref(OBJECT(server_ioc)); 1006 error_report_err(local_err); 1007 return 1; 1008 } 1009 } else { 1010 /* See comment in check_socket_activation above. */ 1011 assert(socket_activation == 1); 1012 server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD, 1013 &local_err); 1014 if (server_ioc == NULL) { 1015 error_report("Failed to use socket activation: %s", 1016 error_get_pretty(local_err)); 1017 exit(EXIT_FAILURE); 1018 } 1019 } 1020 1021 if (qemu_init_main_loop(&local_err)) { 1022 error_report_err(local_err); 1023 exit(EXIT_FAILURE); 1024 } 1025 bdrv_init(); 1026 atexit(bdrv_close_all); 1027 1028 srcpath = argv[optind]; 1029 if (imageOpts) { 1030 QemuOpts *opts; 1031 if (fmt) { 1032 error_report("--image-opts and -f are mutually exclusive"); 1033 exit(EXIT_FAILURE); 1034 } 1035 opts = qemu_opts_parse_noisily(&file_opts, srcpath, true); 1036 if (!opts) { 1037 qemu_opts_reset(&file_opts); 1038 exit(EXIT_FAILURE); 1039 } 1040 options = qemu_opts_to_qdict(opts, NULL); 1041 qemu_opts_reset(&file_opts); 1042 blk = blk_new_open(NULL, NULL, options, flags, &local_err); 1043 } else { 1044 if (fmt) { 1045 options = qdict_new(); 1046 qdict_put(options, "driver", qstring_from_str(fmt)); 1047 } 1048 blk = blk_new_open(srcpath, NULL, options, flags, &local_err); 1049 } 1050 1051 if (!blk) { 1052 error_reportf_err(local_err, "Failed to blk_new_open '%s': ", 1053 argv[optind]); 1054 exit(EXIT_FAILURE); 1055 } 1056 bs = blk_bs(blk); 1057 1058 blk_set_enable_write_cache(blk, !writethrough); 1059 1060 if (sn_opts) { 1061 ret = bdrv_snapshot_load_tmp(bs, 1062 qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), 1063 qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), 1064 &local_err); 1065 } else if (sn_id_or_name) { 1066 ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, 1067 &local_err); 1068 } 1069 if (ret < 0) { 1070 error_reportf_err(local_err, "Failed to load snapshot: "); 1071 exit(EXIT_FAILURE); 1072 } 1073 1074 bs->detect_zeroes = detect_zeroes; 1075 fd_size = blk_getlength(blk); 1076 if (fd_size < 0) { 1077 error_report("Failed to determine the image length: %s", 1078 strerror(-fd_size)); 1079 exit(EXIT_FAILURE); 1080 } 1081 1082 if (dev_offset >= fd_size) { 1083 error_report("Offset (%lld) has to be smaller than the image size " 1084 "(%lld)", 1085 (long long int)dev_offset, (long long int)fd_size); 1086 exit(EXIT_FAILURE); 1087 } 1088 fd_size -= dev_offset; 1089 1090 if (partition != -1) { 1091 ret = find_partition(blk, partition, &dev_offset, &fd_size); 1092 if (ret < 0) { 1093 error_report("Could not find partition %d: %s", partition, 1094 strerror(-ret)); 1095 exit(EXIT_FAILURE); 1096 } 1097 } 1098 1099 exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed, 1100 writethrough, NULL, &local_err); 1101 if (!exp) { 1102 error_report_err(local_err); 1103 exit(EXIT_FAILURE); 1104 } 1105 if (export_name) { 1106 nbd_export_set_name(exp, export_name); 1107 nbd_export_set_description(exp, export_description); 1108 newproto = true; 1109 } else if (export_description) { 1110 error_report("Export description requires an export name"); 1111 exit(EXIT_FAILURE); 1112 } 1113 1114 if (device) { 1115 int ret; 1116 1117 ret = pthread_create(&client_thread, NULL, nbd_client_thread, device); 1118 if (ret != 0) { 1119 error_report("Failed to create client thread: %s", strerror(ret)); 1120 exit(EXIT_FAILURE); 1121 } 1122 } else { 1123 /* Shut up GCC warnings. */ 1124 memset(&client_thread, 0, sizeof(client_thread)); 1125 } 1126 1127 nbd_update_server_watch(); 1128 1129 /* now when the initialization is (almost) complete, chdir("/") 1130 * to free any busy filesystems */ 1131 if (chdir("/") < 0) { 1132 error_report("Could not chdir to root directory: %s", 1133 strerror(errno)); 1134 exit(EXIT_FAILURE); 1135 } 1136 1137 if (fork_process) { 1138 dup2(old_stderr, STDERR_FILENO); 1139 close(old_stderr); 1140 } 1141 1142 state = RUNNING; 1143 do { 1144 main_loop_wait(false); 1145 if (state == TERMINATE) { 1146 state = TERMINATING; 1147 nbd_export_close(exp); 1148 nbd_export_put(exp); 1149 exp = NULL; 1150 } 1151 } while (state != TERMINATED); 1152 1153 blk_unref(blk); 1154 if (sockpath) { 1155 unlink(sockpath); 1156 } 1157 1158 qemu_opts_del(sn_opts); 1159 1160 if (device) { 1161 void *ret; 1162 pthread_join(client_thread, &ret); 1163 exit(ret != NULL); 1164 } else { 1165 exit(EXIT_SUCCESS); 1166 } 1167 } 1168