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 "qemu/osdep.h" 27 #include "tap_int.h" 28 29 30 #include <sys/ioctl.h> 31 #include <sys/wait.h> 32 #include <sys/socket.h> 33 #include <net/if.h> 34 35 #include "net/net.h" 36 #include "clients.h" 37 #include "monitor/monitor.h" 38 #include "sysemu/sysemu.h" 39 #include "qapi/error.h" 40 #include "qemu-common.h" 41 #include "qemu/cutils.h" 42 #include "qemu/error-report.h" 43 44 #include "net/tap.h" 45 46 #include "net/vhost_net.h" 47 48 typedef struct TAPState { 49 NetClientState nc; 50 int fd; 51 char down_script[1024]; 52 char down_script_arg[128]; 53 uint8_t buf[NET_BUFSIZE]; 54 bool read_poll; 55 bool write_poll; 56 bool using_vnet_hdr; 57 bool has_ufo; 58 bool enabled; 59 VHostNetState *vhost_net; 60 unsigned host_vnet_hdr_len; 61 Notifier exit; 62 } TAPState; 63 64 static void launch_script(const char *setup_script, const char *ifname, 65 int fd, Error **errp); 66 67 static void tap_send(void *opaque); 68 static void tap_writable(void *opaque); 69 70 static void tap_update_fd_handler(TAPState *s) 71 { 72 qemu_set_fd_handler(s->fd, 73 s->read_poll && s->enabled ? tap_send : NULL, 74 s->write_poll && s->enabled ? tap_writable : NULL, 75 s); 76 } 77 78 static void tap_read_poll(TAPState *s, bool enable) 79 { 80 s->read_poll = enable; 81 tap_update_fd_handler(s); 82 } 83 84 static void tap_write_poll(TAPState *s, bool enable) 85 { 86 s->write_poll = enable; 87 tap_update_fd_handler(s); 88 } 89 90 static void tap_writable(void *opaque) 91 { 92 TAPState *s = opaque; 93 94 tap_write_poll(s, false); 95 96 qemu_flush_queued_packets(&s->nc); 97 } 98 99 static ssize_t tap_write_packet(TAPState *s, const struct iovec *iov, int iovcnt) 100 { 101 ssize_t len; 102 103 do { 104 len = writev(s->fd, iov, iovcnt); 105 } while (len == -1 && errno == EINTR); 106 107 if (len == -1 && errno == EAGAIN) { 108 tap_write_poll(s, true); 109 return 0; 110 } 111 112 return len; 113 } 114 115 static ssize_t tap_receive_iov(NetClientState *nc, const struct iovec *iov, 116 int iovcnt) 117 { 118 TAPState *s = DO_UPCAST(TAPState, nc, nc); 119 const struct iovec *iovp = iov; 120 struct iovec iov_copy[iovcnt + 1]; 121 struct virtio_net_hdr_mrg_rxbuf hdr = { }; 122 123 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) { 124 iov_copy[0].iov_base = &hdr; 125 iov_copy[0].iov_len = s->host_vnet_hdr_len; 126 memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov)); 127 iovp = iov_copy; 128 iovcnt++; 129 } 130 131 return tap_write_packet(s, iovp, iovcnt); 132 } 133 134 static ssize_t tap_receive_raw(NetClientState *nc, const uint8_t *buf, size_t size) 135 { 136 TAPState *s = DO_UPCAST(TAPState, nc, nc); 137 struct iovec iov[2]; 138 int iovcnt = 0; 139 struct virtio_net_hdr_mrg_rxbuf hdr = { }; 140 141 if (s->host_vnet_hdr_len) { 142 iov[iovcnt].iov_base = &hdr; 143 iov[iovcnt].iov_len = s->host_vnet_hdr_len; 144 iovcnt++; 145 } 146 147 iov[iovcnt].iov_base = (char *)buf; 148 iov[iovcnt].iov_len = size; 149 iovcnt++; 150 151 return tap_write_packet(s, iov, iovcnt); 152 } 153 154 static ssize_t tap_receive(NetClientState *nc, const uint8_t *buf, size_t size) 155 { 156 TAPState *s = DO_UPCAST(TAPState, nc, nc); 157 struct iovec iov[1]; 158 159 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) { 160 return tap_receive_raw(nc, buf, size); 161 } 162 163 iov[0].iov_base = (char *)buf; 164 iov[0].iov_len = size; 165 166 return tap_write_packet(s, iov, 1); 167 } 168 169 #ifndef __sun__ 170 ssize_t tap_read_packet(int tapfd, uint8_t *buf, int maxlen) 171 { 172 return read(tapfd, buf, maxlen); 173 } 174 #endif 175 176 static void tap_send_completed(NetClientState *nc, ssize_t len) 177 { 178 TAPState *s = DO_UPCAST(TAPState, nc, nc); 179 tap_read_poll(s, true); 180 } 181 182 static void tap_send(void *opaque) 183 { 184 TAPState *s = opaque; 185 int size; 186 int packets = 0; 187 188 while (true) { 189 uint8_t *buf = s->buf; 190 191 size = tap_read_packet(s->fd, s->buf, sizeof(s->buf)); 192 if (size <= 0) { 193 break; 194 } 195 196 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) { 197 buf += s->host_vnet_hdr_len; 198 size -= s->host_vnet_hdr_len; 199 } 200 201 size = qemu_send_packet_async(&s->nc, buf, size, tap_send_completed); 202 if (size == 0) { 203 tap_read_poll(s, false); 204 break; 205 } else if (size < 0) { 206 break; 207 } 208 209 /* 210 * When the host keeps receiving more packets while tap_send() is 211 * running we can hog the QEMU global mutex. Limit the number of 212 * packets that are processed per tap_send() callback to prevent 213 * stalling the guest. 214 */ 215 packets++; 216 if (packets >= 50) { 217 break; 218 } 219 } 220 } 221 222 static bool tap_has_ufo(NetClientState *nc) 223 { 224 TAPState *s = DO_UPCAST(TAPState, nc, nc); 225 226 assert(nc->info->type == NET_CLIENT_DRIVER_TAP); 227 228 return s->has_ufo; 229 } 230 231 static bool tap_has_vnet_hdr(NetClientState *nc) 232 { 233 TAPState *s = DO_UPCAST(TAPState, nc, nc); 234 235 assert(nc->info->type == NET_CLIENT_DRIVER_TAP); 236 237 return !!s->host_vnet_hdr_len; 238 } 239 240 static bool tap_has_vnet_hdr_len(NetClientState *nc, int len) 241 { 242 TAPState *s = DO_UPCAST(TAPState, nc, nc); 243 244 assert(nc->info->type == NET_CLIENT_DRIVER_TAP); 245 246 return !!tap_probe_vnet_hdr_len(s->fd, len); 247 } 248 249 static void tap_set_vnet_hdr_len(NetClientState *nc, int len) 250 { 251 TAPState *s = DO_UPCAST(TAPState, nc, nc); 252 253 assert(nc->info->type == NET_CLIENT_DRIVER_TAP); 254 assert(len == sizeof(struct virtio_net_hdr_mrg_rxbuf) || 255 len == sizeof(struct virtio_net_hdr)); 256 257 tap_fd_set_vnet_hdr_len(s->fd, len); 258 s->host_vnet_hdr_len = len; 259 } 260 261 static void tap_using_vnet_hdr(NetClientState *nc, bool using_vnet_hdr) 262 { 263 TAPState *s = DO_UPCAST(TAPState, nc, nc); 264 265 assert(nc->info->type == NET_CLIENT_DRIVER_TAP); 266 assert(!!s->host_vnet_hdr_len == using_vnet_hdr); 267 268 s->using_vnet_hdr = using_vnet_hdr; 269 } 270 271 static int tap_set_vnet_le(NetClientState *nc, bool is_le) 272 { 273 TAPState *s = DO_UPCAST(TAPState, nc, nc); 274 275 return tap_fd_set_vnet_le(s->fd, is_le); 276 } 277 278 static int tap_set_vnet_be(NetClientState *nc, bool is_be) 279 { 280 TAPState *s = DO_UPCAST(TAPState, nc, nc); 281 282 return tap_fd_set_vnet_be(s->fd, is_be); 283 } 284 285 static void tap_set_offload(NetClientState *nc, int csum, int tso4, 286 int tso6, int ecn, int ufo) 287 { 288 TAPState *s = DO_UPCAST(TAPState, nc, nc); 289 if (s->fd < 0) { 290 return; 291 } 292 293 tap_fd_set_offload(s->fd, csum, tso4, tso6, ecn, ufo); 294 } 295 296 static void tap_exit_notify(Notifier *notifier, void *data) 297 { 298 TAPState *s = container_of(notifier, TAPState, exit); 299 Error *err = NULL; 300 301 if (s->down_script[0]) { 302 launch_script(s->down_script, s->down_script_arg, s->fd, &err); 303 if (err) { 304 error_report_err(err); 305 } 306 } 307 } 308 309 static void tap_cleanup(NetClientState *nc) 310 { 311 TAPState *s = DO_UPCAST(TAPState, nc, nc); 312 313 if (s->vhost_net) { 314 vhost_net_cleanup(s->vhost_net); 315 s->vhost_net = NULL; 316 } 317 318 qemu_purge_queued_packets(nc); 319 320 tap_exit_notify(&s->exit, NULL); 321 qemu_remove_exit_notifier(&s->exit); 322 323 tap_read_poll(s, false); 324 tap_write_poll(s, false); 325 close(s->fd); 326 s->fd = -1; 327 } 328 329 static void tap_poll(NetClientState *nc, bool enable) 330 { 331 TAPState *s = DO_UPCAST(TAPState, nc, nc); 332 tap_read_poll(s, enable); 333 tap_write_poll(s, enable); 334 } 335 336 int tap_get_fd(NetClientState *nc) 337 { 338 TAPState *s = DO_UPCAST(TAPState, nc, nc); 339 assert(nc->info->type == NET_CLIENT_DRIVER_TAP); 340 return s->fd; 341 } 342 343 /* fd support */ 344 345 static NetClientInfo net_tap_info = { 346 .type = NET_CLIENT_DRIVER_TAP, 347 .size = sizeof(TAPState), 348 .receive = tap_receive, 349 .receive_raw = tap_receive_raw, 350 .receive_iov = tap_receive_iov, 351 .poll = tap_poll, 352 .cleanup = tap_cleanup, 353 .has_ufo = tap_has_ufo, 354 .has_vnet_hdr = tap_has_vnet_hdr, 355 .has_vnet_hdr_len = tap_has_vnet_hdr_len, 356 .using_vnet_hdr = tap_using_vnet_hdr, 357 .set_offload = tap_set_offload, 358 .set_vnet_hdr_len = tap_set_vnet_hdr_len, 359 .set_vnet_le = tap_set_vnet_le, 360 .set_vnet_be = tap_set_vnet_be, 361 }; 362 363 static TAPState *net_tap_fd_init(NetClientState *peer, 364 const char *model, 365 const char *name, 366 int fd, 367 int vnet_hdr) 368 { 369 NetClientState *nc; 370 TAPState *s; 371 372 nc = qemu_new_net_client(&net_tap_info, peer, model, name); 373 374 s = DO_UPCAST(TAPState, nc, nc); 375 376 s->fd = fd; 377 s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0; 378 s->using_vnet_hdr = false; 379 s->has_ufo = tap_probe_has_ufo(s->fd); 380 s->enabled = true; 381 tap_set_offload(&s->nc, 0, 0, 0, 0, 0); 382 /* 383 * Make sure host header length is set correctly in tap: 384 * it might have been modified by another instance of qemu. 385 */ 386 if (tap_probe_vnet_hdr_len(s->fd, s->host_vnet_hdr_len)) { 387 tap_fd_set_vnet_hdr_len(s->fd, s->host_vnet_hdr_len); 388 } 389 tap_read_poll(s, true); 390 s->vhost_net = NULL; 391 392 s->exit.notify = tap_exit_notify; 393 qemu_add_exit_notifier(&s->exit); 394 395 return s; 396 } 397 398 static void launch_script(const char *setup_script, const char *ifname, 399 int fd, Error **errp) 400 { 401 int pid, status; 402 char *args[3]; 403 char **parg; 404 405 /* try to launch network script */ 406 pid = fork(); 407 if (pid < 0) { 408 error_setg_errno(errp, errno, "could not launch network script %s", 409 setup_script); 410 return; 411 } 412 if (pid == 0) { 413 int open_max = sysconf(_SC_OPEN_MAX), i; 414 415 for (i = 3; i < open_max; i++) { 416 if (i != fd) { 417 close(i); 418 } 419 } 420 parg = args; 421 *parg++ = (char *)setup_script; 422 *parg++ = (char *)ifname; 423 *parg = NULL; 424 execv(setup_script, args); 425 _exit(1); 426 } else { 427 while (waitpid(pid, &status, 0) != pid) { 428 /* loop */ 429 } 430 431 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) { 432 return; 433 } 434 error_setg(errp, "network script %s failed with status %d", 435 setup_script, status); 436 } 437 } 438 439 static int recv_fd(int c) 440 { 441 int fd; 442 uint8_t msgbuf[CMSG_SPACE(sizeof(fd))]; 443 struct msghdr msg = { 444 .msg_control = msgbuf, 445 .msg_controllen = sizeof(msgbuf), 446 }; 447 struct cmsghdr *cmsg; 448 struct iovec iov; 449 uint8_t req[1]; 450 ssize_t len; 451 452 cmsg = CMSG_FIRSTHDR(&msg); 453 cmsg->cmsg_level = SOL_SOCKET; 454 cmsg->cmsg_type = SCM_RIGHTS; 455 cmsg->cmsg_len = CMSG_LEN(sizeof(fd)); 456 msg.msg_controllen = cmsg->cmsg_len; 457 458 iov.iov_base = req; 459 iov.iov_len = sizeof(req); 460 461 msg.msg_iov = &iov; 462 msg.msg_iovlen = 1; 463 464 len = recvmsg(c, &msg, 0); 465 if (len > 0) { 466 memcpy(&fd, CMSG_DATA(cmsg), sizeof(fd)); 467 return fd; 468 } 469 470 return len; 471 } 472 473 static int net_bridge_run_helper(const char *helper, const char *bridge, 474 Error **errp) 475 { 476 sigset_t oldmask, mask; 477 int pid, status; 478 char *args[5]; 479 char **parg; 480 int sv[2]; 481 482 sigemptyset(&mask); 483 sigaddset(&mask, SIGCHLD); 484 sigprocmask(SIG_BLOCK, &mask, &oldmask); 485 486 if (socketpair(PF_UNIX, SOCK_STREAM, 0, sv) == -1) { 487 error_setg_errno(errp, errno, "socketpair() failed"); 488 return -1; 489 } 490 491 /* try to launch bridge helper */ 492 pid = fork(); 493 if (pid < 0) { 494 error_setg_errno(errp, errno, "Can't fork bridge helper"); 495 return -1; 496 } 497 if (pid == 0) { 498 int open_max = sysconf(_SC_OPEN_MAX), i; 499 char fd_buf[6+10]; 500 char br_buf[6+IFNAMSIZ] = {0}; 501 char helper_cmd[PATH_MAX + sizeof(fd_buf) + sizeof(br_buf) + 15]; 502 503 for (i = 3; i < open_max; i++) { 504 if (i != sv[1]) { 505 close(i); 506 } 507 } 508 509 snprintf(fd_buf, sizeof(fd_buf), "%s%d", "--fd=", sv[1]); 510 511 if (strrchr(helper, ' ') || strrchr(helper, '\t')) { 512 /* assume helper is a command */ 513 514 if (strstr(helper, "--br=") == NULL) { 515 snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge); 516 } 517 518 snprintf(helper_cmd, sizeof(helper_cmd), "%s %s %s %s", 519 helper, "--use-vnet", fd_buf, br_buf); 520 521 parg = args; 522 *parg++ = (char *)"sh"; 523 *parg++ = (char *)"-c"; 524 *parg++ = helper_cmd; 525 *parg++ = NULL; 526 527 execv("/bin/sh", args); 528 } else { 529 /* assume helper is just the executable path name */ 530 531 snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge); 532 533 parg = args; 534 *parg++ = (char *)helper; 535 *parg++ = (char *)"--use-vnet"; 536 *parg++ = fd_buf; 537 *parg++ = br_buf; 538 *parg++ = NULL; 539 540 execv(helper, args); 541 } 542 _exit(1); 543 544 } else { 545 int fd; 546 int saved_errno; 547 548 close(sv[1]); 549 550 do { 551 fd = recv_fd(sv[0]); 552 } while (fd == -1 && errno == EINTR); 553 saved_errno = errno; 554 555 close(sv[0]); 556 557 while (waitpid(pid, &status, 0) != pid) { 558 /* loop */ 559 } 560 sigprocmask(SIG_SETMASK, &oldmask, NULL); 561 if (fd < 0) { 562 error_setg_errno(errp, saved_errno, 563 "failed to recv file descriptor"); 564 return -1; 565 } 566 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { 567 error_setg(errp, "bridge helper failed"); 568 return -1; 569 } 570 return fd; 571 } 572 } 573 574 int net_init_bridge(const Netdev *netdev, const char *name, 575 NetClientState *peer, Error **errp) 576 { 577 const NetdevBridgeOptions *bridge; 578 const char *helper, *br; 579 TAPState *s; 580 int fd, vnet_hdr; 581 582 assert(netdev->type == NET_CLIENT_DRIVER_BRIDGE); 583 bridge = &netdev->u.bridge; 584 585 helper = bridge->has_helper ? bridge->helper : DEFAULT_BRIDGE_HELPER; 586 br = bridge->has_br ? bridge->br : DEFAULT_BRIDGE_INTERFACE; 587 588 fd = net_bridge_run_helper(helper, br, errp); 589 if (fd == -1) { 590 return -1; 591 } 592 593 fcntl(fd, F_SETFL, O_NONBLOCK); 594 vnet_hdr = tap_probe_vnet_hdr(fd); 595 s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr); 596 597 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s,br=%s", helper, 598 br); 599 600 return 0; 601 } 602 603 static int net_tap_init(const NetdevTapOptions *tap, int *vnet_hdr, 604 const char *setup_script, char *ifname, 605 size_t ifname_sz, int mq_required, Error **errp) 606 { 607 Error *err = NULL; 608 int fd, vnet_hdr_required; 609 610 if (tap->has_vnet_hdr) { 611 *vnet_hdr = tap->vnet_hdr; 612 vnet_hdr_required = *vnet_hdr; 613 } else { 614 *vnet_hdr = 1; 615 vnet_hdr_required = 0; 616 } 617 618 TFR(fd = tap_open(ifname, ifname_sz, vnet_hdr, vnet_hdr_required, 619 mq_required, errp)); 620 if (fd < 0) { 621 return -1; 622 } 623 624 if (setup_script && 625 setup_script[0] != '\0' && 626 strcmp(setup_script, "no") != 0) { 627 launch_script(setup_script, ifname, fd, &err); 628 if (err) { 629 error_propagate(errp, err); 630 close(fd); 631 return -1; 632 } 633 } 634 635 return fd; 636 } 637 638 #define MAX_TAP_QUEUES 1024 639 640 static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, 641 const char *model, const char *name, 642 const char *ifname, const char *script, 643 const char *downscript, const char *vhostfdname, 644 int vnet_hdr, int fd, Error **errp) 645 { 646 Error *err = NULL; 647 TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); 648 int vhostfd; 649 650 tap_set_sndbuf(s->fd, tap, &err); 651 if (err) { 652 error_propagate(errp, err); 653 return; 654 } 655 656 if (tap->has_fd || tap->has_fds) { 657 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "fd=%d", fd); 658 } else if (tap->has_helper) { 659 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s", 660 tap->helper); 661 } else { 662 snprintf(s->nc.info_str, sizeof(s->nc.info_str), 663 "ifname=%s,script=%s,downscript=%s", ifname, script, 664 downscript); 665 666 if (strcmp(downscript, "no") != 0) { 667 snprintf(s->down_script, sizeof(s->down_script), "%s", downscript); 668 snprintf(s->down_script_arg, sizeof(s->down_script_arg), 669 "%s", ifname); 670 } 671 } 672 673 if (tap->has_vhost ? tap->vhost : 674 vhostfdname || (tap->has_vhostforce && tap->vhostforce)) { 675 VhostNetOptions options; 676 677 options.backend_type = VHOST_BACKEND_TYPE_KERNEL; 678 options.net_backend = &s->nc; 679 if (tap->has_poll_us) { 680 options.busyloop_timeout = tap->poll_us; 681 } else { 682 options.busyloop_timeout = 0; 683 } 684 685 if (vhostfdname) { 686 vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err); 687 if (vhostfd == -1) { 688 error_propagate(errp, err); 689 return; 690 } 691 } else { 692 vhostfd = open("/dev/vhost-net", O_RDWR); 693 if (vhostfd < 0) { 694 error_setg_errno(errp, errno, 695 "tap: open vhost char device failed"); 696 return; 697 } 698 } 699 options.opaque = (void *)(uintptr_t)vhostfd; 700 701 s->vhost_net = vhost_net_init(&options); 702 if (!s->vhost_net) { 703 error_setg(errp, 704 "vhost-net requested but could not be initialized"); 705 return; 706 } 707 } else if (vhostfdname) { 708 error_setg(errp, "vhostfd(s)= is not valid without vhost"); 709 } 710 } 711 712 static int get_fds(char *str, char *fds[], int max) 713 { 714 char *ptr = str, *this; 715 size_t len = strlen(str); 716 int i = 0; 717 718 while (i < max && ptr < str + len) { 719 this = strchr(ptr, ':'); 720 721 if (this == NULL) { 722 fds[i] = g_strdup(ptr); 723 } else { 724 fds[i] = g_strndup(ptr, this - ptr); 725 } 726 727 i++; 728 if (this == NULL) { 729 break; 730 } else { 731 ptr = this + 1; 732 } 733 } 734 735 return i; 736 } 737 738 int net_init_tap(const Netdev *netdev, const char *name, 739 NetClientState *peer, Error **errp) 740 { 741 const NetdevTapOptions *tap; 742 int fd, vnet_hdr = 0, i = 0, queues; 743 /* for the no-fd, no-helper case */ 744 const char *script = NULL; /* suppress wrong "uninit'd use" gcc warning */ 745 const char *downscript = NULL; 746 Error *err = NULL; 747 const char *vhostfdname; 748 char ifname[128]; 749 750 assert(netdev->type == NET_CLIENT_DRIVER_TAP); 751 tap = &netdev->u.tap; 752 queues = tap->has_queues ? tap->queues : 1; 753 vhostfdname = tap->has_vhostfd ? tap->vhostfd : NULL; 754 755 /* QEMU vlans does not support multiqueue tap, in this case peer is set. 756 * For -netdev, peer is always NULL. */ 757 if (peer && (tap->has_queues || tap->has_fds || tap->has_vhostfds)) { 758 error_setg(errp, "Multiqueue tap cannot be used with QEMU vlans"); 759 return -1; 760 } 761 762 if (tap->has_fd) { 763 if (tap->has_ifname || tap->has_script || tap->has_downscript || 764 tap->has_vnet_hdr || tap->has_helper || tap->has_queues || 765 tap->has_fds || tap->has_vhostfds) { 766 error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, " 767 "helper=, queues=, fds=, and vhostfds= " 768 "are invalid with fd="); 769 return -1; 770 } 771 772 fd = monitor_fd_param(cur_mon, tap->fd, &err); 773 if (fd == -1) { 774 error_propagate(errp, err); 775 return -1; 776 } 777 778 fcntl(fd, F_SETFL, O_NONBLOCK); 779 780 vnet_hdr = tap_probe_vnet_hdr(fd); 781 782 net_init_tap_one(tap, peer, "tap", name, NULL, 783 script, downscript, 784 vhostfdname, vnet_hdr, fd, &err); 785 if (err) { 786 error_propagate(errp, err); 787 return -1; 788 } 789 } else if (tap->has_fds) { 790 char **fds = g_new0(char *, MAX_TAP_QUEUES); 791 char **vhost_fds = g_new0(char *, MAX_TAP_QUEUES); 792 int nfds, nvhosts; 793 794 if (tap->has_ifname || tap->has_script || tap->has_downscript || 795 tap->has_vnet_hdr || tap->has_helper || tap->has_queues || 796 tap->has_vhostfd) { 797 error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, " 798 "helper=, queues=, and vhostfd= " 799 "are invalid with fds="); 800 return -1; 801 } 802 803 nfds = get_fds(tap->fds, fds, MAX_TAP_QUEUES); 804 if (tap->has_vhostfds) { 805 nvhosts = get_fds(tap->vhostfds, vhost_fds, MAX_TAP_QUEUES); 806 if (nfds != nvhosts) { 807 error_setg(errp, "The number of fds passed does not match " 808 "the number of vhostfds passed"); 809 goto free_fail; 810 } 811 } 812 813 for (i = 0; i < nfds; i++) { 814 fd = monitor_fd_param(cur_mon, fds[i], &err); 815 if (fd == -1) { 816 error_propagate(errp, err); 817 goto free_fail; 818 } 819 820 fcntl(fd, F_SETFL, O_NONBLOCK); 821 822 if (i == 0) { 823 vnet_hdr = tap_probe_vnet_hdr(fd); 824 } else if (vnet_hdr != tap_probe_vnet_hdr(fd)) { 825 error_setg(errp, 826 "vnet_hdr not consistent across given tap fds"); 827 goto free_fail; 828 } 829 830 net_init_tap_one(tap, peer, "tap", name, ifname, 831 script, downscript, 832 tap->has_vhostfds ? vhost_fds[i] : NULL, 833 vnet_hdr, fd, &err); 834 if (err) { 835 error_propagate(errp, err); 836 goto free_fail; 837 } 838 } 839 g_free(fds); 840 g_free(vhost_fds); 841 return 0; 842 843 free_fail: 844 for (i = 0; i < nfds; i++) { 845 g_free(fds[i]); 846 g_free(vhost_fds[i]); 847 } 848 g_free(fds); 849 g_free(vhost_fds); 850 return -1; 851 } else if (tap->has_helper) { 852 if (tap->has_ifname || tap->has_script || tap->has_downscript || 853 tap->has_vnet_hdr || tap->has_queues || tap->has_vhostfds) { 854 error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, " 855 "queues=, and vhostfds= are invalid with helper="); 856 return -1; 857 } 858 859 fd = net_bridge_run_helper(tap->helper, DEFAULT_BRIDGE_INTERFACE, 860 errp); 861 if (fd == -1) { 862 return -1; 863 } 864 865 fcntl(fd, F_SETFL, O_NONBLOCK); 866 vnet_hdr = tap_probe_vnet_hdr(fd); 867 868 net_init_tap_one(tap, peer, "bridge", name, ifname, 869 script, downscript, vhostfdname, 870 vnet_hdr, fd, &err); 871 if (err) { 872 error_propagate(errp, err); 873 close(fd); 874 return -1; 875 } 876 } else { 877 if (tap->has_vhostfds) { 878 error_setg(errp, "vhostfds= is invalid if fds= wasn't specified"); 879 return -1; 880 } 881 script = tap->has_script ? tap->script : DEFAULT_NETWORK_SCRIPT; 882 downscript = tap->has_downscript ? tap->downscript : 883 DEFAULT_NETWORK_DOWN_SCRIPT; 884 885 if (tap->has_ifname) { 886 pstrcpy(ifname, sizeof ifname, tap->ifname); 887 } else { 888 ifname[0] = '\0'; 889 } 890 891 for (i = 0; i < queues; i++) { 892 fd = net_tap_init(tap, &vnet_hdr, i >= 1 ? "no" : script, 893 ifname, sizeof ifname, queues > 1, errp); 894 if (fd == -1) { 895 return -1; 896 } 897 898 if (queues > 1 && i == 0 && !tap->has_ifname) { 899 if (tap_fd_get_ifname(fd, ifname)) { 900 error_setg(errp, "Fail to get ifname"); 901 close(fd); 902 return -1; 903 } 904 } 905 906 net_init_tap_one(tap, peer, "tap", name, ifname, 907 i >= 1 ? "no" : script, 908 i >= 1 ? "no" : downscript, 909 vhostfdname, vnet_hdr, fd, &err); 910 if (err) { 911 error_propagate(errp, err); 912 close(fd); 913 return -1; 914 } 915 } 916 } 917 918 return 0; 919 } 920 921 VHostNetState *tap_get_vhost_net(NetClientState *nc) 922 { 923 TAPState *s = DO_UPCAST(TAPState, nc, nc); 924 assert(nc->info->type == NET_CLIENT_DRIVER_TAP); 925 return s->vhost_net; 926 } 927 928 int tap_enable(NetClientState *nc) 929 { 930 TAPState *s = DO_UPCAST(TAPState, nc, nc); 931 int ret; 932 933 if (s->enabled) { 934 return 0; 935 } else { 936 ret = tap_fd_enable(s->fd); 937 if (ret == 0) { 938 s->enabled = true; 939 tap_update_fd_handler(s); 940 } 941 return ret; 942 } 943 } 944 945 int tap_disable(NetClientState *nc) 946 { 947 TAPState *s = DO_UPCAST(TAPState, nc, nc); 948 int ret; 949 950 if (s->enabled == 0) { 951 return 0; 952 } else { 953 ret = tap_fd_disable(s->fd); 954 if (ret == 0) { 955 qemu_purge_queued_packets(nc); 956 s->enabled = false; 957 tap_update_fd_handler(s); 958 } 959 return ret; 960 } 961 } 962