trap signals for "-serial mon:stdio"
[qemu.git] / net / tap.c
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 int launch_script(const char *setup_script, const char *ifname, int fd);
63
64 static int tap_can_send(void *opaque);
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_handler2(s->fd,
71 s->read_poll && s->enabled ? tap_can_send : NULL,
72 s->read_poll && s->enabled ? tap_send : NULL,
73 s->write_poll && s->enabled ? tap_writable : NULL,
74 s);
75 }
76
77 static void tap_read_poll(TAPState *s, bool enable)
78 {
79 s->read_poll = enable;
80 tap_update_fd_handler(s);
81 }
82
83 static void tap_write_poll(TAPState *s, bool enable)
84 {
85 s->write_poll = enable;
86 tap_update_fd_handler(s);
87 }
88
89 static void tap_writable(void *opaque)
90 {
91 TAPState *s = opaque;
92
93 tap_write_poll(s, false);
94
95 qemu_flush_queued_packets(&s->nc);
96 }
97
98 static ssize_t tap_write_packet(TAPState *s, const struct iovec *iov, int iovcnt)
99 {
100 ssize_t len;
101
102 do {
103 len = writev(s->fd, iov, iovcnt);
104 } while (len == -1 && errno == EINTR);
105
106 if (len == -1 && errno == EAGAIN) {
107 tap_write_poll(s, true);
108 return 0;
109 }
110
111 return len;
112 }
113
114 static ssize_t tap_receive_iov(NetClientState *nc, const struct iovec *iov,
115 int iovcnt)
116 {
117 TAPState *s = DO_UPCAST(TAPState, nc, nc);
118 const struct iovec *iovp = iov;
119 struct iovec iov_copy[iovcnt + 1];
120 struct virtio_net_hdr_mrg_rxbuf hdr = { };
121
122 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
123 iov_copy[0].iov_base = &hdr;
124 iov_copy[0].iov_len = s->host_vnet_hdr_len;
125 memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov));
126 iovp = iov_copy;
127 iovcnt++;
128 }
129
130 return tap_write_packet(s, iovp, iovcnt);
131 }
132
133 static ssize_t tap_receive_raw(NetClientState *nc, const uint8_t *buf, size_t size)
134 {
135 TAPState *s = DO_UPCAST(TAPState, nc, nc);
136 struct iovec iov[2];
137 int iovcnt = 0;
138 struct virtio_net_hdr_mrg_rxbuf hdr = { };
139
140 if (s->host_vnet_hdr_len) {
141 iov[iovcnt].iov_base = &hdr;
142 iov[iovcnt].iov_len = s->host_vnet_hdr_len;
143 iovcnt++;
144 }
145
146 iov[iovcnt].iov_base = (char *)buf;
147 iov[iovcnt].iov_len = size;
148 iovcnt++;
149
150 return tap_write_packet(s, iov, iovcnt);
151 }
152
153 static ssize_t tap_receive(NetClientState *nc, const uint8_t *buf, size_t size)
154 {
155 TAPState *s = DO_UPCAST(TAPState, nc, nc);
156 struct iovec iov[1];
157
158 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
159 return tap_receive_raw(nc, buf, size);
160 }
161
162 iov[0].iov_base = (char *)buf;
163 iov[0].iov_len = size;
164
165 return tap_write_packet(s, iov, 1);
166 }
167
168 static int tap_can_send(void *opaque)
169 {
170 TAPState *s = opaque;
171
172 return qemu_can_send_packet(&s->nc);
173 }
174
175 #ifndef __sun__
176 ssize_t tap_read_packet(int tapfd, uint8_t *buf, int maxlen)
177 {
178 return read(tapfd, buf, maxlen);
179 }
180 #endif
181
182 static void tap_send_completed(NetClientState *nc, ssize_t len)
183 {
184 TAPState *s = DO_UPCAST(TAPState, nc, nc);
185 tap_read_poll(s, true);
186 }
187
188 static void tap_send(void *opaque)
189 {
190 TAPState *s = opaque;
191 int size;
192
193 do {
194 uint8_t *buf = s->buf;
195
196 size = tap_read_packet(s->fd, s->buf, sizeof(s->buf));
197 if (size <= 0) {
198 break;
199 }
200
201 if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
202 buf += s->host_vnet_hdr_len;
203 size -= s->host_vnet_hdr_len;
204 }
205
206 size = qemu_send_packet_async(&s->nc, buf, size, tap_send_completed);
207 if (size == 0) {
208 tap_read_poll(s, false);
209 }
210 } while (size > 0 && qemu_can_send_packet(&s->nc));
211 }
212
213 bool tap_has_ufo(NetClientState *nc)
214 {
215 TAPState *s = DO_UPCAST(TAPState, nc, nc);
216
217 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
218
219 return s->has_ufo;
220 }
221
222 int tap_has_vnet_hdr(NetClientState *nc)
223 {
224 TAPState *s = DO_UPCAST(TAPState, nc, nc);
225
226 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
227
228 return !!s->host_vnet_hdr_len;
229 }
230
231 int tap_has_vnet_hdr_len(NetClientState *nc, int len)
232 {
233 TAPState *s = DO_UPCAST(TAPState, nc, nc);
234
235 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
236
237 return tap_probe_vnet_hdr_len(s->fd, len);
238 }
239
240 void tap_set_vnet_hdr_len(NetClientState *nc, int len)
241 {
242 TAPState *s = DO_UPCAST(TAPState, nc, nc);
243
244 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
245 assert(len == sizeof(struct virtio_net_hdr_mrg_rxbuf) ||
246 len == sizeof(struct virtio_net_hdr));
247
248 tap_fd_set_vnet_hdr_len(s->fd, len);
249 s->host_vnet_hdr_len = len;
250 }
251
252 void tap_using_vnet_hdr(NetClientState *nc, bool using_vnet_hdr)
253 {
254 TAPState *s = DO_UPCAST(TAPState, nc, nc);
255
256 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
257 assert(!!s->host_vnet_hdr_len == using_vnet_hdr);
258
259 s->using_vnet_hdr = using_vnet_hdr;
260 }
261
262 void tap_set_offload(NetClientState *nc, int csum, int tso4,
263 int tso6, int ecn, int ufo)
264 {
265 TAPState *s = DO_UPCAST(TAPState, nc, nc);
266 if (s->fd < 0) {
267 return;
268 }
269
270 tap_fd_set_offload(s->fd, csum, tso4, tso6, ecn, ufo);
271 }
272
273 static void tap_cleanup(NetClientState *nc)
274 {
275 TAPState *s = DO_UPCAST(TAPState, nc, nc);
276
277 if (s->vhost_net) {
278 vhost_net_cleanup(s->vhost_net);
279 s->vhost_net = NULL;
280 }
281
282 qemu_purge_queued_packets(nc);
283
284 if (s->down_script[0])
285 launch_script(s->down_script, s->down_script_arg, s->fd);
286
287 tap_read_poll(s, false);
288 tap_write_poll(s, false);
289 close(s->fd);
290 s->fd = -1;
291 }
292
293 static void tap_poll(NetClientState *nc, bool enable)
294 {
295 TAPState *s = DO_UPCAST(TAPState, nc, nc);
296 tap_read_poll(s, enable);
297 tap_write_poll(s, enable);
298 }
299
300 int tap_get_fd(NetClientState *nc)
301 {
302 TAPState *s = DO_UPCAST(TAPState, nc, nc);
303 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
304 return s->fd;
305 }
306
307 /* fd support */
308
309 static NetClientInfo net_tap_info = {
310 .type = NET_CLIENT_OPTIONS_KIND_TAP,
311 .size = sizeof(TAPState),
312 .receive = tap_receive,
313 .receive_raw = tap_receive_raw,
314 .receive_iov = tap_receive_iov,
315 .poll = tap_poll,
316 .cleanup = tap_cleanup,
317 };
318
319 static TAPState *net_tap_fd_init(NetClientState *peer,
320 const char *model,
321 const char *name,
322 int fd,
323 int vnet_hdr)
324 {
325 NetClientState *nc;
326 TAPState *s;
327
328 nc = qemu_new_net_client(&net_tap_info, peer, model, name);
329
330 s = DO_UPCAST(TAPState, nc, nc);
331
332 s->fd = fd;
333 s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0;
334 s->using_vnet_hdr = false;
335 s->has_ufo = tap_probe_has_ufo(s->fd);
336 s->enabled = true;
337 tap_set_offload(&s->nc, 0, 0, 0, 0, 0);
338 /*
339 * Make sure host header length is set correctly in tap:
340 * it might have been modified by another instance of qemu.
341 */
342 if (tap_probe_vnet_hdr_len(s->fd, s->host_vnet_hdr_len)) {
343 tap_fd_set_vnet_hdr_len(s->fd, s->host_vnet_hdr_len);
344 }
345 tap_read_poll(s, true);
346 s->vhost_net = NULL;
347 return s;
348 }
349
350 static int launch_script(const char *setup_script, const char *ifname, int fd)
351 {
352 int pid, status;
353 char *args[3];
354 char **parg;
355
356 /* try to launch network script */
357 pid = fork();
358 if (pid == 0) {
359 int open_max = sysconf(_SC_OPEN_MAX), i;
360
361 for (i = 0; i < open_max; i++) {
362 if (i != STDIN_FILENO &&
363 i != STDOUT_FILENO &&
364 i != STDERR_FILENO &&
365 i != fd) {
366 close(i);
367 }
368 }
369 parg = args;
370 *parg++ = (char *)setup_script;
371 *parg++ = (char *)ifname;
372 *parg = NULL;
373 execv(setup_script, args);
374 _exit(1);
375 } else if (pid > 0) {
376 while (waitpid(pid, &status, 0) != pid) {
377 /* loop */
378 }
379
380 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
381 return 0;
382 }
383 }
384 fprintf(stderr, "%s: could not launch network script\n", setup_script);
385 return -1;
386 }
387
388 static int recv_fd(int c)
389 {
390 int fd;
391 uint8_t msgbuf[CMSG_SPACE(sizeof(fd))];
392 struct msghdr msg = {
393 .msg_control = msgbuf,
394 .msg_controllen = sizeof(msgbuf),
395 };
396 struct cmsghdr *cmsg;
397 struct iovec iov;
398 uint8_t req[1];
399 ssize_t len;
400
401 cmsg = CMSG_FIRSTHDR(&msg);
402 cmsg->cmsg_level = SOL_SOCKET;
403 cmsg->cmsg_type = SCM_RIGHTS;
404 cmsg->cmsg_len = CMSG_LEN(sizeof(fd));
405 msg.msg_controllen = cmsg->cmsg_len;
406
407 iov.iov_base = req;
408 iov.iov_len = sizeof(req);
409
410 msg.msg_iov = &iov;
411 msg.msg_iovlen = 1;
412
413 len = recvmsg(c, &msg, 0);
414 if (len > 0) {
415 memcpy(&fd, CMSG_DATA(cmsg), sizeof(fd));
416 return fd;
417 }
418
419 return len;
420 }
421
422 static int net_bridge_run_helper(const char *helper, const char *bridge)
423 {
424 sigset_t oldmask, mask;
425 int pid, status;
426 char *args[5];
427 char **parg;
428 int sv[2];
429
430 sigemptyset(&mask);
431 sigaddset(&mask, SIGCHLD);
432 sigprocmask(SIG_BLOCK, &mask, &oldmask);
433
434 if (socketpair(PF_UNIX, SOCK_STREAM, 0, sv) == -1) {
435 return -1;
436 }
437
438 /* try to launch bridge helper */
439 pid = fork();
440 if (pid == 0) {
441 int open_max = sysconf(_SC_OPEN_MAX), i;
442 char fd_buf[6+10];
443 char br_buf[6+IFNAMSIZ] = {0};
444 char helper_cmd[PATH_MAX + sizeof(fd_buf) + sizeof(br_buf) + 15];
445
446 for (i = 0; i < open_max; i++) {
447 if (i != STDIN_FILENO &&
448 i != STDOUT_FILENO &&
449 i != STDERR_FILENO &&
450 i != sv[1]) {
451 close(i);
452 }
453 }
454
455 snprintf(fd_buf, sizeof(fd_buf), "%s%d", "--fd=", sv[1]);
456
457 if (strrchr(helper, ' ') || strrchr(helper, '\t')) {
458 /* assume helper is a command */
459
460 if (strstr(helper, "--br=") == NULL) {
461 snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge);
462 }
463
464 snprintf(helper_cmd, sizeof(helper_cmd), "%s %s %s %s",
465 helper, "--use-vnet", fd_buf, br_buf);
466
467 parg = args;
468 *parg++ = (char *)"sh";
469 *parg++ = (char *)"-c";
470 *parg++ = helper_cmd;
471 *parg++ = NULL;
472
473 execv("/bin/sh", args);
474 } else {
475 /* assume helper is just the executable path name */
476
477 snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge);
478
479 parg = args;
480 *parg++ = (char *)helper;
481 *parg++ = (char *)"--use-vnet";
482 *parg++ = fd_buf;
483 *parg++ = br_buf;
484 *parg++ = NULL;
485
486 execv(helper, args);
487 }
488 _exit(1);
489
490 } else if (pid > 0) {
491 int fd;
492
493 close(sv[1]);
494
495 do {
496 fd = recv_fd(sv[0]);
497 } while (fd == -1 && errno == EINTR);
498
499 close(sv[0]);
500
501 while (waitpid(pid, &status, 0) != pid) {
502 /* loop */
503 }
504 sigprocmask(SIG_SETMASK, &oldmask, NULL);
505 if (fd < 0) {
506 fprintf(stderr, "failed to recv file descriptor\n");
507 return -1;
508 }
509
510 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
511 return fd;
512 }
513 }
514 fprintf(stderr, "failed to launch bridge helper\n");
515 return -1;
516 }
517
518 int net_init_bridge(const NetClientOptions *opts, const char *name,
519 NetClientState *peer)
520 {
521 const NetdevBridgeOptions *bridge;
522 const char *helper, *br;
523
524 TAPState *s;
525 int fd, vnet_hdr;
526
527 assert(opts->kind == NET_CLIENT_OPTIONS_KIND_BRIDGE);
528 bridge = opts->bridge;
529
530 helper = bridge->has_helper ? bridge->helper : DEFAULT_BRIDGE_HELPER;
531 br = bridge->has_br ? bridge->br : DEFAULT_BRIDGE_INTERFACE;
532
533 fd = net_bridge_run_helper(helper, br);
534 if (fd == -1) {
535 return -1;
536 }
537
538 fcntl(fd, F_SETFL, O_NONBLOCK);
539
540 vnet_hdr = tap_probe_vnet_hdr(fd);
541
542 s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr);
543 if (!s) {
544 close(fd);
545 return -1;
546 }
547
548 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s,br=%s", helper,
549 br);
550
551 return 0;
552 }
553
554 static int net_tap_init(const NetdevTapOptions *tap, int *vnet_hdr,
555 const char *setup_script, char *ifname,
556 size_t ifname_sz, int mq_required)
557 {
558 int fd, vnet_hdr_required;
559
560 if (tap->has_vnet_hdr) {
561 *vnet_hdr = tap->vnet_hdr;
562 vnet_hdr_required = *vnet_hdr;
563 } else {
564 *vnet_hdr = 1;
565 vnet_hdr_required = 0;
566 }
567
568 TFR(fd = tap_open(ifname, ifname_sz, vnet_hdr, vnet_hdr_required,
569 mq_required));
570 if (fd < 0) {
571 return -1;
572 }
573
574 if (setup_script &&
575 setup_script[0] != '\0' &&
576 strcmp(setup_script, "no") != 0 &&
577 launch_script(setup_script, ifname, fd)) {
578 close(fd);
579 return -1;
580 }
581
582 return fd;
583 }
584
585 #define MAX_TAP_QUEUES 1024
586
587 static int net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
588 const char *model, const char *name,
589 const char *ifname, const char *script,
590 const char *downscript, const char *vhostfdname,
591 int vnet_hdr, int fd)
592 {
593 TAPState *s;
594
595 s = net_tap_fd_init(peer, model, name, fd, vnet_hdr);
596 if (!s) {
597 close(fd);
598 return -1;
599 }
600
601 if (tap_set_sndbuf(s->fd, tap) < 0) {
602 return -1;
603 }
604
605 if (tap->has_fd || tap->has_fds) {
606 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "fd=%d", fd);
607 } else if (tap->has_helper) {
608 snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s",
609 tap->helper);
610 } else {
611 snprintf(s->nc.info_str, sizeof(s->nc.info_str),
612 "ifname=%s,script=%s,downscript=%s", ifname, script,
613 downscript);
614
615 if (strcmp(downscript, "no") != 0) {
616 snprintf(s->down_script, sizeof(s->down_script), "%s", downscript);
617 snprintf(s->down_script_arg, sizeof(s->down_script_arg),
618 "%s", ifname);
619 }
620 }
621
622 if (tap->has_vhost ? tap->vhost :
623 vhostfdname || (tap->has_vhostforce && tap->vhostforce)) {
624 int vhostfd;
625
626 if (tap->has_vhostfd || tap->has_vhostfds) {
627 vhostfd = monitor_handle_fd_param(cur_mon, vhostfdname);
628 if (vhostfd == -1) {
629 return -1;
630 }
631 } else {
632 vhostfd = -1;
633 }
634
635 s->vhost_net = vhost_net_init(&s->nc, vhostfd,
636 tap->has_vhostforce && tap->vhostforce);
637 if (!s->vhost_net) {
638 error_report("vhost-net requested but could not be initialized");
639 return -1;
640 }
641 } else if (tap->has_vhostfd || tap->has_vhostfds) {
642 error_report("vhostfd= is not valid without vhost");
643 return -1;
644 }
645
646 return 0;
647 }
648
649 static int get_fds(char *str, char *fds[], int max)
650 {
651 char *ptr = str, *this;
652 size_t len = strlen(str);
653 int i = 0;
654
655 while (i < max && ptr < str + len) {
656 this = strchr(ptr, ':');
657
658 if (this == NULL) {
659 fds[i] = g_strdup(ptr);
660 } else {
661 fds[i] = g_strndup(ptr, this - ptr);
662 }
663
664 i++;
665 if (this == NULL) {
666 break;
667 } else {
668 ptr = this + 1;
669 }
670 }
671
672 return i;
673 }
674
675 int net_init_tap(const NetClientOptions *opts, const char *name,
676 NetClientState *peer)
677 {
678 const NetdevTapOptions *tap;
679 int fd, vnet_hdr = 0, i = 0, queues;
680 /* for the no-fd, no-helper case */
681 const char *script = NULL; /* suppress wrong "uninit'd use" gcc warning */
682 const char *downscript = NULL;
683 const char *vhostfdname;
684 char ifname[128];
685
686 assert(opts->kind == NET_CLIENT_OPTIONS_KIND_TAP);
687 tap = opts->tap;
688 queues = tap->has_queues ? tap->queues : 1;
689 vhostfdname = tap->has_vhostfd ? tap->vhostfd : NULL;
690
691 /* QEMU vlans does not support multiqueue tap, in this case peer is set.
692 * For -netdev, peer is always NULL. */
693 if (peer && (tap->has_queues || tap->has_fds || tap->has_vhostfds)) {
694 error_report("Multiqueue tap cannot be used with QEMU vlans");
695 return -1;
696 }
697
698 if (tap->has_fd) {
699 if (tap->has_ifname || tap->has_script || tap->has_downscript ||
700 tap->has_vnet_hdr || tap->has_helper || tap->has_queues ||
701 tap->has_fds || tap->has_vhostfds) {
702 error_report("ifname=, script=, downscript=, vnet_hdr=, "
703 "helper=, queues=, fds=, and vhostfds= "
704 "are invalid with fd=");
705 return -1;
706 }
707
708 fd = monitor_handle_fd_param(cur_mon, tap->fd);
709 if (fd == -1) {
710 return -1;
711 }
712
713 fcntl(fd, F_SETFL, O_NONBLOCK);
714
715 vnet_hdr = tap_probe_vnet_hdr(fd);
716
717 if (net_init_tap_one(tap, peer, "tap", name, NULL,
718 script, downscript,
719 vhostfdname, vnet_hdr, fd)) {
720 return -1;
721 }
722 } else if (tap->has_fds) {
723 char *fds[MAX_TAP_QUEUES];
724 char *vhost_fds[MAX_TAP_QUEUES];
725 int nfds, nvhosts;
726
727 if (tap->has_ifname || tap->has_script || tap->has_downscript ||
728 tap->has_vnet_hdr || tap->has_helper || tap->has_queues ||
729 tap->has_vhostfd) {
730 error_report("ifname=, script=, downscript=, vnet_hdr=, "
731 "helper=, queues=, and vhostfd= "
732 "are invalid with fds=");
733 return -1;
734 }
735
736 nfds = get_fds(tap->fds, fds, MAX_TAP_QUEUES);
737 if (tap->has_vhostfds) {
738 nvhosts = get_fds(tap->vhostfds, vhost_fds, MAX_TAP_QUEUES);
739 if (nfds != nvhosts) {
740 error_report("The number of fds passed does not match the "
741 "number of vhostfds passed");
742 return -1;
743 }
744 }
745
746 for (i = 0; i < nfds; i++) {
747 fd = monitor_handle_fd_param(cur_mon, fds[i]);
748 if (fd == -1) {
749 return -1;
750 }
751
752 fcntl(fd, F_SETFL, O_NONBLOCK);
753
754 if (i == 0) {
755 vnet_hdr = tap_probe_vnet_hdr(fd);
756 } else if (vnet_hdr != tap_probe_vnet_hdr(fd)) {
757 error_report("vnet_hdr not consistent across given tap fds");
758 return -1;
759 }
760
761 if (net_init_tap_one(tap, peer, "tap", name, ifname,
762 script, downscript,
763 tap->has_vhostfds ? vhost_fds[i] : NULL,
764 vnet_hdr, fd)) {
765 return -1;
766 }
767 }
768 } else if (tap->has_helper) {
769 if (tap->has_ifname || tap->has_script || tap->has_downscript ||
770 tap->has_vnet_hdr || tap->has_queues || tap->has_vhostfds) {
771 error_report("ifname=, script=, downscript=, and vnet_hdr= "
772 "queues=, and vhostfds= are invalid with helper=");
773 return -1;
774 }
775
776 fd = net_bridge_run_helper(tap->helper, DEFAULT_BRIDGE_INTERFACE);
777 if (fd == -1) {
778 return -1;
779 }
780
781 fcntl(fd, F_SETFL, O_NONBLOCK);
782 vnet_hdr = tap_probe_vnet_hdr(fd);
783
784 if (net_init_tap_one(tap, peer, "bridge", name, ifname,
785 script, downscript, vhostfdname,
786 vnet_hdr, fd)) {
787 return -1;
788 }
789 } else {
790 if (tap->has_vhostfds) {
791 error_report("vhostfds= is invalid if fds= wasn't specified");
792 return -1;
793 }
794 script = tap->has_script ? tap->script : DEFAULT_NETWORK_SCRIPT;
795 downscript = tap->has_downscript ? tap->downscript :
796 DEFAULT_NETWORK_DOWN_SCRIPT;
797
798 if (tap->has_ifname) {
799 pstrcpy(ifname, sizeof ifname, tap->ifname);
800 } else {
801 ifname[0] = '\0';
802 }
803
804 for (i = 0; i < queues; i++) {
805 fd = net_tap_init(tap, &vnet_hdr, i >= 1 ? "no" : script,
806 ifname, sizeof ifname, queues > 1);
807 if (fd == -1) {
808 return -1;
809 }
810
811 if (queues > 1 && i == 0 && !tap->has_ifname) {
812 if (tap_fd_get_ifname(fd, ifname)) {
813 error_report("Fail to get ifname");
814 return -1;
815 }
816 }
817
818 if (net_init_tap_one(tap, peer, "tap", name, ifname,
819 i >= 1 ? "no" : script,
820 i >= 1 ? "no" : downscript,
821 vhostfdname, vnet_hdr, fd)) {
822 return -1;
823 }
824 }
825 }
826
827 return 0;
828 }
829
830 VHostNetState *tap_get_vhost_net(NetClientState *nc)
831 {
832 TAPState *s = DO_UPCAST(TAPState, nc, nc);
833 assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
834 return s->vhost_net;
835 }
836
837 int tap_enable(NetClientState *nc)
838 {
839 TAPState *s = DO_UPCAST(TAPState, nc, nc);
840 int ret;
841
842 if (s->enabled) {
843 return 0;
844 } else {
845 ret = tap_fd_enable(s->fd);
846 if (ret == 0) {
847 s->enabled = true;
848 tap_update_fd_handler(s);
849 }
850 return ret;
851 }
852 }
853
854 int tap_disable(NetClientState *nc)
855 {
856 TAPState *s = DO_UPCAST(TAPState, nc, nc);
857 int ret;
858
859 if (s->enabled == 0) {
860 return 0;
861 } else {
862 ret = tap_fd_disable(s->fd);
863 if (ret == 0) {
864 qemu_purge_queued_packets(nc);
865 s->enabled = false;
866 tap_update_fd_handler(s);
867 }
868 return ret;
869 }
870 }