1 /* 2 * QEMU System Emulator 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * Copyright (c) 2009 Red Hat, Inc. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy 8 * of this software and associated documentation files (the "Software"), to deal 9 * in the Software without restriction, including without limitation the rights 10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 * copies of the Software, and to permit persons to whom the Software is 12 * furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in 15 * all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 23 * THE SOFTWARE. 24 */ 25 26 #include "tap_int.h" 27 28 #include "config-host.h" 29 30 #include <sys/ioctl.h> 31 #include <sys/stat.h> 32 #include <sys/wait.h> 33 #include <sys/socket.h> 34 #include <net/if.h> 35 36 #include "net/net.h" 37 #include "clients.h" 38 #include "monitor/monitor.h" 39 #include "sysemu/sysemu.h" 40 #include "qemu-common.h" 41 #include "qemu/error-report.h" 42 43 #include "net/tap.h" 44 45 #include "net/vhost_net.h" 46 47 typedef struct TAPState { 48 NetClientState nc; 49 int fd; 50 char down_script[1024]; 51 char down_script_arg[128]; 52 uint8_t buf[NET_BUFSIZE]; 53 bool read_poll; 54 bool write_poll; 55 bool using_vnet_hdr; 56 bool has_ufo; 57 bool enabled; 58 VHostNetState *vhost_net; 59 unsigned host_vnet_hdr_len; 60 } TAPState; 61 62 static void launch_script(const char *setup_script, const char *ifname, 63 int fd, Error **errp); 64 65 static void tap_send(void *opaque); 66 static void tap_writable(void *opaque); 67 68 static void tap_update_fd_handler(TAPState *s) 69 { 70 qemu_set_fd_handler(s->fd, 71 s->read_poll && s->enabled ? tap_send : NULL, 72 s->write_poll && s->enabled ? tap_writable : NULL, 73 s); 74 } 75 76 static void tap_read_poll(TAPState *s, bool enable) 77 { 78 s->read_poll = enable; 79 tap_update_fd_handler(s); 80 } 81 82 static void tap_write_poll(TAPState *s, bool enable) 83 { 84 s->write_poll = enable; 85 tap_update_fd_handler(s); 86 } 87 88 static void tap_writable(void *opaque) 89 { 90 TAPState *s = opaque; 91 92 tap_write_poll(s, false); 93 94 qemu_flush_queued_packets(&s->nc); 95 } 96 97 static ssize_t tap_write_packet(TAPState *s, const struct iovec *iov, int iovcnt) 98 { 99 ssize_t len; 100 101 do { 102 len = writev(s->fd, iov, iovcnt); 103 } while (len == -1 && errno == EINTR); 104 105 if (len == -1 && errno == EAGAIN) { 106 tap_write_poll(s, true); 107 return 0; 108 } 109 110 return len; 111 } 112 113 static ssize_t tap_receive_iov(NetClientState *nc, const struct iovec *iov, 114 int iovcnt) 115 { 116 TAPState *s = DO_UPCAST(TAPState, nc, nc); 117 const struct iovec *iovp = iov; 118 struct iovec iov_copy[iovcnt + 1]; 119 struct virtio_net_hdr_mrg_rxbuf hdr = { }; 120 121 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) { 122 iov_copy[0].iov_base = &hdr; 123 iov_copy[0].iov_len = s->host_vnet_hdr_len; 124 memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov)); 125 iovp = iov_copy; 126 iovcnt++; 127 } 128 129 return tap_write_packet(s, iovp, iovcnt); 130 } 131 132 static ssize_t tap_receive_raw(NetClientState *nc, const uint8_t *buf, size_t size) 133 { 134 TAPState *s = DO_UPCAST(TAPState, nc, nc); 135 struct iovec iov[2]; 136 int iovcnt = 0; 137 struct virtio_net_hdr_mrg_rxbuf hdr = { }; 138 139 if (s->host_vnet_hdr_len) { 140 iov[iovcnt].iov_base = &hdr; 141 iov[iovcnt].iov_len = s->host_vnet_hdr_len; 142 iovcnt++; 143 } 144 145 iov[iovcnt].iov_base = (char *)buf; 146 iov[iovcnt].iov_len = size; 147 iovcnt++; 148 149 return tap_write_packet(s, iov, iovcnt); 150 } 151 152 static ssize_t tap_receive(NetClientState *nc, const uint8_t *buf, size_t size) 153 { 154 TAPState *s = DO_UPCAST(TAPState, nc, nc); 155 struct iovec iov[1]; 156 157 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) { 158 return tap_receive_raw(nc, buf, size); 159 } 160 161 iov[0].iov_base = (char *)buf; 162 iov[0].iov_len = size; 163 164 return tap_write_packet(s, iov, 1); 165 } 166 167 #ifndef __sun__ 168 ssize_t tap_read_packet(int tapfd, uint8_t *buf, int maxlen) 169 { 170 return read(tapfd, buf, maxlen); 171 } 172 #endif 173 174 static void tap_send_completed(NetClientState *nc, ssize_t len) 175 { 176 TAPState *s = DO_UPCAST(TAPState, nc, nc); 177 tap_read_poll(s, true); 178 } 179 180 static void tap_send(void *opaque) 181 { 182 TAPState *s = opaque; 183 int size; 184 int packets = 0; 185 186 while (true) { 187 uint8_t *buf = s->buf; 188 189 size = tap_read_packet(s->fd, s->buf, sizeof(s->buf)); 190 if (size <= 0) { 191 break; 192 } 193 194 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) { 195 buf += s->host_vnet_hdr_len; 196 size -= s->host_vnet_hdr_len; 197 } 198 199 size = qemu_send_packet_async(&s->nc, buf, size, tap_send_completed); 200 if (size == 0) { 201 tap_read_poll(s, false); 202 break; 203 } else if (size < 0) { 204 break; 205 } 206 207 /* 208 * When the host keeps receiving more packets while tap_send() is 209 * running we can hog the QEMU global mutex. Limit the number of 210 * packets that are processed per tap_send() callback to prevent 211 * stalling the guest. 212 */ 213 packets++; 214 if (packets >= 50) { 215 break; 216 } 217 } 218 } 219 220 static bool tap_has_ufo(NetClientState *nc) 221 { 222 TAPState *s = DO_UPCAST(TAPState, nc, nc); 223 224 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); 225 226 return s->has_ufo; 227 } 228 229 static bool tap_has_vnet_hdr(NetClientState *nc) 230 { 231 TAPState *s = DO_UPCAST(TAPState, nc, nc); 232 233 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); 234 235 return !!s->host_vnet_hdr_len; 236 } 237 238 static bool tap_has_vnet_hdr_len(NetClientState *nc, int len) 239 { 240 TAPState *s = DO_UPCAST(TAPState, nc, nc); 241 242 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); 243 244 return !!tap_probe_vnet_hdr_len(s->fd, len); 245 } 246 247 static void tap_set_vnet_hdr_len(NetClientState *nc, int len) 248 { 249 TAPState *s = DO_UPCAST(TAPState, nc, nc); 250 251 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); 252 assert(len == sizeof(struct virtio_net_hdr_mrg_rxbuf) || 253 len == sizeof(struct virtio_net_hdr)); 254 255 tap_fd_set_vnet_hdr_len(s->fd, len); 256 s->host_vnet_hdr_len = len; 257 } 258 259 static void tap_using_vnet_hdr(NetClientState *nc, bool using_vnet_hdr) 260 { 261 TAPState *s = DO_UPCAST(TAPState, nc, nc); 262 263 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); 264 assert(!!s->host_vnet_hdr_len == using_vnet_hdr); 265 266 s->using_vnet_hdr = using_vnet_hdr; 267 } 268 269 static void tap_set_offload(NetClientState *nc, int csum, int tso4, 270 int tso6, int ecn, int ufo) 271 { 272 TAPState *s = DO_UPCAST(TAPState, nc, nc); 273 if (s->fd < 0) { 274 return; 275 } 276 277 tap_fd_set_offload(s->fd, csum, tso4, tso6, ecn, ufo); 278 } 279 280 static void tap_cleanup(NetClientState *nc) 281 { 282 TAPState *s = DO_UPCAST(TAPState, nc, nc); 283 Error *err = NULL; 284 285 if (s->vhost_net) { 286 vhost_net_cleanup(s->vhost_net); 287 s->vhost_net = NULL; 288 } 289 290 qemu_purge_queued_packets(nc); 291 292 if (s->down_script[0]) { 293 launch_script(s->down_script, s->down_script_arg, s->fd, &err); 294 if (err) { 295 error_report_err(err); 296 } 297 } 298 299 tap_read_poll(s, false); 300 tap_write_poll(s, false); 301 close(s->fd); 302 s->fd = -1; 303 } 304 305 static void tap_poll(NetClientState *nc, bool enable) 306 { 307 TAPState *s = DO_UPCAST(TAPState, nc, nc); 308 tap_read_poll(s, enable); 309 tap_write_poll(s, enable); 310 } 311 312 int tap_get_fd(NetClientState *nc) 313 { 314 TAPState *s = DO_UPCAST(TAPState, nc, nc); 315 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); 316 return s->fd; 317 } 318 319 /* fd support */ 320 321 static NetClientInfo net_tap_info = { 322 .type = NET_CLIENT_OPTIONS_KIND_TAP, 323 .size = sizeof(TAPState), 324 .receive = tap_receive, 325 .receive_raw = tap_receive_raw, 326 .receive_iov = tap_receive_iov, 327 .poll = tap_poll, 328 .cleanup = tap_cleanup, 329 .has_ufo = tap_has_ufo, 330 .has_vnet_hdr = tap_has_vnet_hdr, 331 .has_vnet_hdr_len = tap_has_vnet_hdr_len, 332 .using_vnet_hdr = tap_using_vnet_hdr, 333 .set_offload = tap_set_offload, 334 .set_vnet_hdr_len = tap_set_vnet_hdr_len, 335 }; 336 337 static TAPState *net_tap_fd_init(NetClientState *peer, 338 const char *model, 339 const char *name, 340 int fd, 341 int vnet_hdr) 342 { 343 NetClientState *nc; 344 TAPState *s; 345 346 nc = qemu_new_net_client(&net_tap_info, peer, model, name); 347 348 s = DO_UPCAST(TAPState, nc, nc); 349 350 s->fd = fd; 351 s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0; 352 s->using_vnet_hdr = false; 353 s->has_ufo = tap_probe_has_ufo(s->fd); 354 s->enabled = true; 355 tap_set_offload(&s->nc, 0, 0, 0, 0, 0); 356 /* 357 * Make sure host header length is set correctly in tap: 358 * it might have been modified by another instance of qemu. 359 */ 360 if (tap_probe_vnet_hdr_len(s->fd, s->host_vnet_hdr_len)) { 361 tap_fd_set_vnet_hdr_len(s->fd, s->host_vnet_hdr_len); 362 } 363 tap_read_poll(s, true); 364 s->vhost_net = NULL; 365 return s; 366 } 367 368 static void launch_script(const char *setup_script, const char *ifname, 369 int fd, Error **errp) 370 { 371 int pid, status; 372 char *args[3]; 373 char **parg; 374 375 /* try to launch network script */ 376 pid = fork(); 377 if (pid < 0) { 378 error_setg_errno(errp, errno, "could not launch network script %s", 379 setup_script); 380 return; 381 } 382 if (pid == 0) { 383 int open_max = sysconf(_SC_OPEN_MAX), i; 384 385 for (i = 3; i < open_max; i++) { 386 if (i != fd) { 387 close(i); 388 } 389 } 390 parg = args; 391 *parg++ = (char *)setup_script; 392 *parg++ = (char *)ifname; 393 *parg = NULL; 394 execv(setup_script, args); 395 _exit(1); 396 } else { 397 while (waitpid(pid, &status, 0) != pid) { 398 /* loop */ 399 } 400 401 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) { 402 return; 403 } 404 error_setg(errp, "network script %s failed with status %d", 405 setup_script, status); 406 } 407 } 408 409 static int recv_fd(int c) 410 { 411 int fd; 412 uint8_t msgbuf[CMSG_SPACE(sizeof(fd))]; 413 struct msghdr msg = { 414 .msg_control = msgbuf, 415 .msg_controllen = sizeof(msgbuf), 416 }; 417 struct cmsghdr *cmsg; 418 struct iovec iov; 419 uint8_t req[1]; 420 ssize_t len; 421 422 cmsg = CMSG_FIRSTHDR(&msg); 423 cmsg->cmsg_level = SOL_SOCKET; 424 cmsg->cmsg_type = SCM_RIGHTS; 425 cmsg->cmsg_len = CMSG_LEN(sizeof(fd)); 426 msg.msg_controllen = cmsg->cmsg_len; 427 428 iov.iov_base = req; 429 iov.iov_len = sizeof(req); 430 431 msg.msg_iov = &iov; 432 msg.msg_iovlen = 1; 433 434 len = recvmsg(c, &msg, 0); 435 if (len > 0) { 436 memcpy(&fd, CMSG_DATA(cmsg), sizeof(fd)); 437 return fd; 438 } 439 440 return len; 441 } 442 443 static int net_bridge_run_helper(const char *helper, const char *bridge, 444 Error **errp) 445 { 446 sigset_t oldmask, mask; 447 int pid, status; 448 char *args[5]; 449 char **parg; 450 int sv[2]; 451 452 sigemptyset(&mask); 453 sigaddset(&mask, SIGCHLD); 454 sigprocmask(SIG_BLOCK, &mask, &oldmask); 455 456 if (socketpair(PF_UNIX, SOCK_STREAM, 0, sv) == -1) { 457 error_setg_errno(errp, errno, "socketpair() failed"); 458 return -1; 459 } 460 461 /* try to launch bridge helper */ 462 pid = fork(); 463 if (pid < 0) { 464 error_setg_errno(errp, errno, "Can't fork bridge helper"); 465 return -1; 466 } 467 if (pid == 0) { 468 int open_max = sysconf(_SC_OPEN_MAX), i; 469 char fd_buf[6+10]; 470 char br_buf[6+IFNAMSIZ] = {0}; 471 char helper_cmd[PATH_MAX + sizeof(fd_buf) + sizeof(br_buf) + 15]; 472 473 for (i = 3; i < open_max; i++) { 474 if (i != sv[1]) { 475 close(i); 476 } 477 } 478 479 snprintf(fd_buf, sizeof(fd_buf), "%s%d", "--fd=", sv[1]); 480 481 if (strrchr(helper, ' ') || strrchr(helper, '\t')) { 482 /* assume helper is a command */ 483 484 if (strstr(helper, "--br=") == NULL) { 485 snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge); 486 } 487 488 snprintf(helper_cmd, sizeof(helper_cmd), "%s %s %s %s", 489 helper, "--use-vnet", fd_buf, br_buf); 490 491 parg = args; 492 *parg++ = (char *)"sh"; 493 *parg++ = (char *)"-c"; 494 *parg++ = helper_cmd; 495 *parg++ = NULL; 496 497 execv("/bin/sh", args); 498 } else { 499 /* assume helper is just the executable path name */ 500 501 snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge); 502 503 parg = args; 504 *parg++ = (char *)helper; 505 *parg++ = (char *)"--use-vnet"; 506 *parg++ = fd_buf; 507 *parg++ = br_buf; 508 *parg++ = NULL; 509 510 execv(helper, args); 511 } 512 _exit(1); 513 514 } else { 515 int fd; 516 int saved_errno; 517 518 close(sv[1]); 519 520 do { 521 fd = recv_fd(sv[0]); 522 } while (fd == -1 && errno == EINTR); 523 saved_errno = errno; 524 525 close(sv[0]); 526 527 while (waitpid(pid, &status, 0) != pid) { 528 /* loop */ 529 } 530 sigprocmask(SIG_SETMASK, &oldmask, NULL); 531 if (fd < 0) { 532 error_setg_errno(errp, saved_errno, 533 "failed to recv file descriptor"); 534 return -1; 535 } 536 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { 537 error_setg(errp, "bridge helper failed"); 538 return -1; 539 } 540 return fd; 541 } 542 } 543 544 int net_init_bridge(const NetClientOptions *opts, const char *name, 545 NetClientState *peer, Error **errp) 546 { 547 const NetdevBridgeOptions *bridge; 548 const char *helper, *br; 549 TAPState *s; 550 int fd, vnet_hdr; 551 552 assert(opts->kind == NET_CLIENT_OPTIONS_KIND_BRIDGE); 553 bridge = opts->bridge; 554 555 helper = bridge->has_helper ? bridge->helper : DEFAULT_BRIDGE_HELPER; 556 br = bridge->has_br ? bridge->br : DEFAULT_BRIDGE_INTERFACE; 557 558 fd = net_bridge_run_helper(helper, br, errp); 559 if (fd == -1) { 560 return -1; 561 } 562 563 fcntl(fd, F_SETFL, O_NONBLOCK); 564 vnet_hdr = tap_probe_vnet_hdr(fd); 565 s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr); 566 567 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s,br=%s", helper, 568 br); 569 570 return 0; 571 } 572 573 static int net_tap_init(const NetdevTapOptions *tap, int *vnet_hdr, 574 const char *setup_script, char *ifname, 575 size_t ifname_sz, int mq_required, Error **errp) 576 { 577 Error *err = NULL; 578 int fd, vnet_hdr_required; 579 580 if (tap->has_vnet_hdr) { 581 *vnet_hdr = tap->vnet_hdr; 582 vnet_hdr_required = *vnet_hdr; 583 } else { 584 *vnet_hdr = 1; 585 vnet_hdr_required = 0; 586 } 587 588 TFR(fd = tap_open(ifname, ifname_sz, vnet_hdr, vnet_hdr_required, 589 mq_required, errp)); 590 if (fd < 0) { 591 return -1; 592 } 593 594 if (setup_script && 595 setup_script[0] != '\0' && 596 strcmp(setup_script, "no") != 0) { 597 launch_script(setup_script, ifname, fd, &err); 598 if (err) { 599 error_propagate(errp, err); 600 close(fd); 601 return -1; 602 } 603 } 604 605 return fd; 606 } 607 608 #define MAX_TAP_QUEUES 1024 609 610 static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, 611 const char *model, const char *name, 612 const char *ifname, const char *script, 613 const char *downscript, const char *vhostfdname, 614 int vnet_hdr, int fd, Error **errp) 615 { 616 Error *err = NULL; 617 TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); 618 int vhostfd; 619 620 tap_set_sndbuf(s->fd, tap, &err); 621 if (err) { 622 error_propagate(errp, err); 623 return; 624 } 625 626 if (tap->has_fd || tap->has_fds) { 627 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "fd=%d", fd); 628 } else if (tap->has_helper) { 629 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s", 630 tap->helper); 631 } else { 632 snprintf(s->nc.info_str, sizeof(s->nc.info_str), 633 "ifname=%s,script=%s,downscript=%s", ifname, script, 634 downscript); 635 636 if (strcmp(downscript, "no") != 0) { 637 snprintf(s->down_script, sizeof(s->down_script), "%s", downscript); 638 snprintf(s->down_script_arg, sizeof(s->down_script_arg), 639 "%s", ifname); 640 } 641 } 642 643 if (tap->has_vhost ? tap->vhost : 644 vhostfdname || (tap->has_vhostforce && tap->vhostforce)) { 645 VhostNetOptions options; 646 647 options.backend_type = VHOST_BACKEND_TYPE_KERNEL; 648 options.net_backend = &s->nc; 649 options.force = tap->has_vhostforce && tap->vhostforce; 650 651 if (tap->has_vhostfd || tap->has_vhostfds) { 652 vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err); 653 if (vhostfd == -1) { 654 error_propagate(errp, err); 655 return; 656 } 657 } else { 658 vhostfd = open("/dev/vhost-net", O_RDWR); 659 if (vhostfd < 0) { 660 error_setg_errno(errp, errno, 661 "tap: open vhost char device failed"); 662 return; 663 } 664 } 665 options.opaque = (void *)(uintptr_t)vhostfd; 666 667 s->vhost_net = vhost_net_init(&options); 668 if (!s->vhost_net) { 669 error_setg(errp, 670 "vhost-net requested but could not be initialized"); 671 return; 672 } 673 } else if (tap->has_vhostfd || tap->has_vhostfds) { 674 error_setg(errp, "vhostfd= is not valid without vhost"); 675 } 676 } 677 678 static int get_fds(char *str, char *fds[], int max) 679 { 680 char *ptr = str, *this; 681 size_t len = strlen(str); 682 int i = 0; 683 684 while (i < max && ptr < str + len) { 685 this = strchr(ptr, ':'); 686 687 if (this == NULL) { 688 fds[i] = g_strdup(ptr); 689 } else { 690 fds[i] = g_strndup(ptr, this - ptr); 691 } 692 693 i++; 694 if (this == NULL) { 695 break; 696 } else { 697 ptr = this + 1; 698 } 699 } 700 701 return i; 702 } 703 704 int net_init_tap(const NetClientOptions *opts, const char *name, 705 NetClientState *peer, Error **errp) 706 { 707 const NetdevTapOptions *tap; 708 int fd, vnet_hdr = 0, i = 0, queues; 709 /* for the no-fd, no-helper case */ 710 const char *script = NULL; /* suppress wrong "uninit'd use" gcc warning */ 711 const char *downscript = NULL; 712 Error *err = NULL; 713 const char *vhostfdname; 714 char ifname[128]; 715 716 assert(opts->kind == NET_CLIENT_OPTIONS_KIND_TAP); 717 tap = opts->tap; 718 queues = tap->has_queues ? tap->queues : 1; 719 vhostfdname = tap->has_vhostfd ? tap->vhostfd : NULL; 720 721 /* QEMU vlans does not support multiqueue tap, in this case peer is set. 722 * For -netdev, peer is always NULL. */ 723 if (peer && (tap->has_queues || tap->has_fds || tap->has_vhostfds)) { 724 error_setg(errp, "Multiqueue tap cannot be used with QEMU vlans"); 725 return -1; 726 } 727 728 if (tap->has_fd) { 729 if (tap->has_ifname || tap->has_script || tap->has_downscript || 730 tap->has_vnet_hdr || tap->has_helper || tap->has_queues || 731 tap->has_fds || tap->has_vhostfds) { 732 error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, " 733 "helper=, queues=, fds=, and vhostfds= " 734 "are invalid with fd="); 735 return -1; 736 } 737 738 fd = monitor_fd_param(cur_mon, tap->fd, &err); 739 if (fd == -1) { 740 error_propagate(errp, err); 741 return -1; 742 } 743 744 fcntl(fd, F_SETFL, O_NONBLOCK); 745 746 vnet_hdr = tap_probe_vnet_hdr(fd); 747 748 net_init_tap_one(tap, peer, "tap", name, NULL, 749 script, downscript, 750 vhostfdname, vnet_hdr, fd, &err); 751 if (err) { 752 error_propagate(errp, err); 753 return -1; 754 } 755 } else if (tap->has_fds) { 756 char *fds[MAX_TAP_QUEUES]; 757 char *vhost_fds[MAX_TAP_QUEUES]; 758 int nfds, nvhosts; 759 760 if (tap->has_ifname || tap->has_script || tap->has_downscript || 761 tap->has_vnet_hdr || tap->has_helper || tap->has_queues || 762 tap->has_vhostfd) { 763 error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, " 764 "helper=, queues=, and vhostfd= " 765 "are invalid with fds="); 766 return -1; 767 } 768 769 nfds = get_fds(tap->fds, fds, MAX_TAP_QUEUES); 770 if (tap->has_vhostfds) { 771 nvhosts = get_fds(tap->vhostfds, vhost_fds, MAX_TAP_QUEUES); 772 if (nfds != nvhosts) { 773 error_setg(errp, "The number of fds passed does not match " 774 "the number of vhostfds passed"); 775 return -1; 776 } 777 } 778 779 for (i = 0; i < nfds; i++) { 780 fd = monitor_fd_param(cur_mon, fds[i], &err); 781 if (fd == -1) { 782 error_propagate(errp, err); 783 return -1; 784 } 785 786 fcntl(fd, F_SETFL, O_NONBLOCK); 787 788 if (i == 0) { 789 vnet_hdr = tap_probe_vnet_hdr(fd); 790 } else if (vnet_hdr != tap_probe_vnet_hdr(fd)) { 791 error_setg(errp, 792 "vnet_hdr not consistent across given tap fds"); 793 return -1; 794 } 795 796 net_init_tap_one(tap, peer, "tap", name, ifname, 797 script, downscript, 798 tap->has_vhostfds ? vhost_fds[i] : NULL, 799 vnet_hdr, fd, &err); 800 if (err) { 801 error_propagate(errp, err); 802 return -1; 803 } 804 } 805 } else if (tap->has_helper) { 806 if (tap->has_ifname || tap->has_script || tap->has_downscript || 807 tap->has_vnet_hdr || tap->has_queues || tap->has_vhostfds) { 808 error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, " 809 "queues=, and vhostfds= are invalid with helper="); 810 return -1; 811 } 812 813 fd = net_bridge_run_helper(tap->helper, DEFAULT_BRIDGE_INTERFACE, 814 errp); 815 if (fd == -1) { 816 return -1; 817 } 818 819 fcntl(fd, F_SETFL, O_NONBLOCK); 820 vnet_hdr = tap_probe_vnet_hdr(fd); 821 822 net_init_tap_one(tap, peer, "bridge", name, ifname, 823 script, downscript, vhostfdname, 824 vnet_hdr, fd, &err); 825 if (err) { 826 error_propagate(errp, err); 827 close(fd); 828 return -1; 829 } 830 } else { 831 if (tap->has_vhostfds) { 832 error_setg(errp, "vhostfds= is invalid if fds= wasn't specified"); 833 return -1; 834 } 835 script = tap->has_script ? tap->script : DEFAULT_NETWORK_SCRIPT; 836 downscript = tap->has_downscript ? tap->downscript : 837 DEFAULT_NETWORK_DOWN_SCRIPT; 838 839 if (tap->has_ifname) { 840 pstrcpy(ifname, sizeof ifname, tap->ifname); 841 } else { 842 ifname[0] = '\0'; 843 } 844 845 for (i = 0; i < queues; i++) { 846 fd = net_tap_init(tap, &vnet_hdr, i >= 1 ? "no" : script, 847 ifname, sizeof ifname, queues > 1, errp); 848 if (fd == -1) { 849 return -1; 850 } 851 852 if (queues > 1 && i == 0 && !tap->has_ifname) { 853 if (tap_fd_get_ifname(fd, ifname)) { 854 error_setg(errp, "Fail to get ifname"); 855 close(fd); 856 return -1; 857 } 858 } 859 860 net_init_tap_one(tap, peer, "tap", name, ifname, 861 i >= 1 ? "no" : script, 862 i >= 1 ? "no" : downscript, 863 vhostfdname, vnet_hdr, fd, &err); 864 if (err) { 865 error_propagate(errp, err); 866 close(fd); 867 return -1; 868 } 869 } 870 } 871 872 return 0; 873 } 874 875 VHostNetState *tap_get_vhost_net(NetClientState *nc) 876 { 877 TAPState *s = DO_UPCAST(TAPState, nc, nc); 878 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); 879 return s->vhost_net; 880 } 881 882 int tap_enable(NetClientState *nc) 883 { 884 TAPState *s = DO_UPCAST(TAPState, nc, nc); 885 int ret; 886 887 if (s->enabled) { 888 return 0; 889 } else { 890 ret = tap_fd_enable(s->fd); 891 if (ret == 0) { 892 s->enabled = true; 893 tap_update_fd_handler(s); 894 } 895 return ret; 896 } 897 } 898 899 int tap_disable(NetClientState *nc) 900 { 901 TAPState *s = DO_UPCAST(TAPState, nc, nc); 902 int ret; 903 904 if (s->enabled == 0) { 905 return 0; 906 } else { 907 ret = tap_fd_disable(s->fd); 908 if (ret == 0) { 909 qemu_purge_queued_packets(nc); 910 s->enabled = false; 911 tap_update_fd_handler(s); 912 } 913 return ret; 914 } 915 } 916