linux-user: stack_base is now mandatory on all targets
[qemu.git] / hw / virtio-net.c
1 /*
2 * Virtio Network Device
3 *
4 * Copyright IBM, Corp. 2007
5 *
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 */
13
14 #include "iov.h"
15 #include "virtio.h"
16 #include "net.h"
17 #include "net/checksum.h"
18 #include "net/tap.h"
19 #include "qemu-error.h"
20 #include "qemu-timer.h"
21 #include "virtio-net.h"
22 #include "vhost_net.h"
23
24 #define VIRTIO_NET_VM_VERSION 11
25
26 #define MAC_TABLE_ENTRIES 64
27 #define MAX_VLAN (1 << 12) /* Per 802.1Q definition */
28
29 typedef struct VirtIONet
30 {
31 VirtIODevice vdev;
32 uint8_t mac[ETH_ALEN];
33 uint16_t status;
34 VirtQueue *rx_vq;
35 VirtQueue *tx_vq;
36 VirtQueue *ctrl_vq;
37 NICState *nic;
38 QEMUTimer *tx_timer;
39 QEMUBH *tx_bh;
40 uint32_t tx_timeout;
41 int32_t tx_burst;
42 int tx_waiting;
43 uint32_t has_vnet_hdr;
44 uint8_t has_ufo;
45 struct {
46 VirtQueueElement elem;
47 ssize_t len;
48 } async_tx;
49 int mergeable_rx_bufs;
50 uint8_t promisc;
51 uint8_t allmulti;
52 uint8_t alluni;
53 uint8_t nomulti;
54 uint8_t nouni;
55 uint8_t nobcast;
56 uint8_t vhost_started;
57 struct {
58 int in_use;
59 int first_multi;
60 uint8_t multi_overflow;
61 uint8_t uni_overflow;
62 uint8_t *macs;
63 } mac_table;
64 uint32_t *vlans;
65 DeviceState *qdev;
66 } VirtIONet;
67
68 /* TODO
69 * - we could suppress RX interrupt if we were so inclined.
70 */
71
72 static VirtIONet *to_virtio_net(VirtIODevice *vdev)
73 {
74 return (VirtIONet *)vdev;
75 }
76
77 static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
78 {
79 VirtIONet *n = to_virtio_net(vdev);
80 struct virtio_net_config netcfg;
81
82 stw_p(&netcfg.status, n->status);
83 memcpy(netcfg.mac, n->mac, ETH_ALEN);
84 memcpy(config, &netcfg, sizeof(netcfg));
85 }
86
87 static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
88 {
89 VirtIONet *n = to_virtio_net(vdev);
90 struct virtio_net_config netcfg;
91
92 memcpy(&netcfg, config, sizeof(netcfg));
93
94 if (memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
95 memcpy(n->mac, netcfg.mac, ETH_ALEN);
96 qemu_format_nic_info_str(&n->nic->nc, n->mac);
97 }
98 }
99
100 static bool virtio_net_started(VirtIONet *n, uint8_t status)
101 {
102 return (status & VIRTIO_CONFIG_S_DRIVER_OK) &&
103 (n->status & VIRTIO_NET_S_LINK_UP) && n->vdev.vm_running;
104 }
105
106 static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
107 {
108 if (!n->nic->nc.peer) {
109 return;
110 }
111 if (n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
112 return;
113 }
114
115 if (!tap_get_vhost_net(n->nic->nc.peer)) {
116 return;
117 }
118 if (!!n->vhost_started == virtio_net_started(n, status) &&
119 !n->nic->nc.peer->link_down) {
120 return;
121 }
122 if (!n->vhost_started) {
123 int r;
124 if (!vhost_net_query(tap_get_vhost_net(n->nic->nc.peer), &n->vdev)) {
125 return;
126 }
127 r = vhost_net_start(tap_get_vhost_net(n->nic->nc.peer), &n->vdev);
128 if (r < 0) {
129 error_report("unable to start vhost net: %d: "
130 "falling back on userspace virtio", -r);
131 } else {
132 n->vhost_started = 1;
133 }
134 } else {
135 vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), &n->vdev);
136 n->vhost_started = 0;
137 }
138 }
139
140 static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
141 {
142 VirtIONet *n = to_virtio_net(vdev);
143
144 virtio_net_vhost_status(n, status);
145
146 if (!n->tx_waiting) {
147 return;
148 }
149
150 if (virtio_net_started(n, status) && !n->vhost_started) {
151 if (n->tx_timer) {
152 qemu_mod_timer(n->tx_timer,
153 qemu_get_clock_ns(vm_clock) + n->tx_timeout);
154 } else {
155 qemu_bh_schedule(n->tx_bh);
156 }
157 } else {
158 if (n->tx_timer) {
159 qemu_del_timer(n->tx_timer);
160 } else {
161 qemu_bh_cancel(n->tx_bh);
162 }
163 }
164 }
165
166 static void virtio_net_set_link_status(VLANClientState *nc)
167 {
168 VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
169 uint16_t old_status = n->status;
170
171 if (nc->link_down)
172 n->status &= ~VIRTIO_NET_S_LINK_UP;
173 else
174 n->status |= VIRTIO_NET_S_LINK_UP;
175
176 if (n->status != old_status)
177 virtio_notify_config(&n->vdev);
178
179 virtio_net_set_status(&n->vdev, n->vdev.status);
180 }
181
182 static void virtio_net_reset(VirtIODevice *vdev)
183 {
184 VirtIONet *n = to_virtio_net(vdev);
185
186 /* Reset back to compatibility mode */
187 n->promisc = 1;
188 n->allmulti = 0;
189 n->alluni = 0;
190 n->nomulti = 0;
191 n->nouni = 0;
192 n->nobcast = 0;
193
194 /* Flush any MAC and VLAN filter table state */
195 n->mac_table.in_use = 0;
196 n->mac_table.first_multi = 0;
197 n->mac_table.multi_overflow = 0;
198 n->mac_table.uni_overflow = 0;
199 memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
200 memset(n->vlans, 0, MAX_VLAN >> 3);
201 }
202
203 static int peer_has_vnet_hdr(VirtIONet *n)
204 {
205 if (!n->nic->nc.peer)
206 return 0;
207
208 if (n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP)
209 return 0;
210
211 n->has_vnet_hdr = tap_has_vnet_hdr(n->nic->nc.peer);
212
213 return n->has_vnet_hdr;
214 }
215
216 static int peer_has_ufo(VirtIONet *n)
217 {
218 if (!peer_has_vnet_hdr(n))
219 return 0;
220
221 n->has_ufo = tap_has_ufo(n->nic->nc.peer);
222
223 return n->has_ufo;
224 }
225
226 static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
227 {
228 VirtIONet *n = to_virtio_net(vdev);
229
230 features |= (1 << VIRTIO_NET_F_MAC);
231
232 if (peer_has_vnet_hdr(n)) {
233 tap_using_vnet_hdr(n->nic->nc.peer, 1);
234 } else {
235 features &= ~(0x1 << VIRTIO_NET_F_CSUM);
236 features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO4);
237 features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO6);
238 features &= ~(0x1 << VIRTIO_NET_F_HOST_ECN);
239
240 features &= ~(0x1 << VIRTIO_NET_F_GUEST_CSUM);
241 features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO4);
242 features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO6);
243 features &= ~(0x1 << VIRTIO_NET_F_GUEST_ECN);
244 }
245
246 if (!peer_has_vnet_hdr(n) || !peer_has_ufo(n)) {
247 features &= ~(0x1 << VIRTIO_NET_F_GUEST_UFO);
248 features &= ~(0x1 << VIRTIO_NET_F_HOST_UFO);
249 }
250
251 if (!n->nic->nc.peer ||
252 n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
253 return features;
254 }
255 if (!tap_get_vhost_net(n->nic->nc.peer)) {
256 return features;
257 }
258 return vhost_net_get_features(tap_get_vhost_net(n->nic->nc.peer), features);
259 }
260
261 static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
262 {
263 uint32_t features = 0;
264
265 /* Linux kernel 2.6.25. It understood MAC (as everyone must),
266 * but also these: */
267 features |= (1 << VIRTIO_NET_F_MAC);
268 features |= (1 << VIRTIO_NET_F_CSUM);
269 features |= (1 << VIRTIO_NET_F_HOST_TSO4);
270 features |= (1 << VIRTIO_NET_F_HOST_TSO6);
271 features |= (1 << VIRTIO_NET_F_HOST_ECN);
272
273 return features;
274 }
275
276 static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
277 {
278 VirtIONet *n = to_virtio_net(vdev);
279
280 n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF));
281
282 if (n->has_vnet_hdr) {
283 tap_set_offload(n->nic->nc.peer,
284 (features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
285 (features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
286 (features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
287 (features >> VIRTIO_NET_F_GUEST_ECN) & 1,
288 (features >> VIRTIO_NET_F_GUEST_UFO) & 1);
289 }
290 if (!n->nic->nc.peer ||
291 n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
292 return;
293 }
294 if (!tap_get_vhost_net(n->nic->nc.peer)) {
295 return;
296 }
297 vhost_net_ack_features(tap_get_vhost_net(n->nic->nc.peer), features);
298 }
299
300 static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
301 VirtQueueElement *elem)
302 {
303 uint8_t on;
304
305 if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(on)) {
306 error_report("virtio-net ctrl invalid rx mode command");
307 exit(1);
308 }
309
310 on = ldub_p(elem->out_sg[1].iov_base);
311
312 if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC)
313 n->promisc = on;
314 else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI)
315 n->allmulti = on;
316 else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLUNI)
317 n->alluni = on;
318 else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOMULTI)
319 n->nomulti = on;
320 else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOUNI)
321 n->nouni = on;
322 else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOBCAST)
323 n->nobcast = on;
324 else
325 return VIRTIO_NET_ERR;
326
327 return VIRTIO_NET_OK;
328 }
329
330 static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
331 VirtQueueElement *elem)
332 {
333 struct virtio_net_ctrl_mac mac_data;
334
335 if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
336 elem->out_sg[1].iov_len < sizeof(mac_data) ||
337 elem->out_sg[2].iov_len < sizeof(mac_data))
338 return VIRTIO_NET_ERR;
339
340 n->mac_table.in_use = 0;
341 n->mac_table.first_multi = 0;
342 n->mac_table.uni_overflow = 0;
343 n->mac_table.multi_overflow = 0;
344 memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
345
346 mac_data.entries = ldl_p(elem->out_sg[1].iov_base);
347
348 if (sizeof(mac_data.entries) +
349 (mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len)
350 return VIRTIO_NET_ERR;
351
352 if (mac_data.entries <= MAC_TABLE_ENTRIES) {
353 memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data),
354 mac_data.entries * ETH_ALEN);
355 n->mac_table.in_use += mac_data.entries;
356 } else {
357 n->mac_table.uni_overflow = 1;
358 }
359
360 n->mac_table.first_multi = n->mac_table.in_use;
361
362 mac_data.entries = ldl_p(elem->out_sg[2].iov_base);
363
364 if (sizeof(mac_data.entries) +
365 (mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len)
366 return VIRTIO_NET_ERR;
367
368 if (mac_data.entries) {
369 if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
370 memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN),
371 elem->out_sg[2].iov_base + sizeof(mac_data),
372 mac_data.entries * ETH_ALEN);
373 n->mac_table.in_use += mac_data.entries;
374 } else {
375 n->mac_table.multi_overflow = 1;
376 }
377 }
378
379 return VIRTIO_NET_OK;
380 }
381
382 static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
383 VirtQueueElement *elem)
384 {
385 uint16_t vid;
386
387 if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(vid)) {
388 error_report("virtio-net ctrl invalid vlan command");
389 return VIRTIO_NET_ERR;
390 }
391
392 vid = lduw_p(elem->out_sg[1].iov_base);
393
394 if (vid >= MAX_VLAN)
395 return VIRTIO_NET_ERR;
396
397 if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
398 n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
399 else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
400 n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
401 else
402 return VIRTIO_NET_ERR;
403
404 return VIRTIO_NET_OK;
405 }
406
407 static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
408 {
409 VirtIONet *n = to_virtio_net(vdev);
410 struct virtio_net_ctrl_hdr ctrl;
411 virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
412 VirtQueueElement elem;
413
414 while (virtqueue_pop(vq, &elem)) {
415 if ((elem.in_num < 1) || (elem.out_num < 1)) {
416 error_report("virtio-net ctrl missing headers");
417 exit(1);
418 }
419
420 if (elem.out_sg[0].iov_len < sizeof(ctrl) ||
421 elem.in_sg[elem.in_num - 1].iov_len < sizeof(status)) {
422 error_report("virtio-net ctrl header not in correct element");
423 exit(1);
424 }
425
426 ctrl.class = ldub_p(elem.out_sg[0].iov_base);
427 ctrl.cmd = ldub_p(elem.out_sg[0].iov_base + sizeof(ctrl.class));
428
429 if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE)
430 status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem);
431 else if (ctrl.class == VIRTIO_NET_CTRL_MAC)
432 status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
433 else if (ctrl.class == VIRTIO_NET_CTRL_VLAN)
434 status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem);
435
436 stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
437
438 virtqueue_push(vq, &elem, sizeof(status));
439 virtio_notify(vdev, vq);
440 }
441 }
442
443 /* RX */
444
445 static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
446 {
447 VirtIONet *n = to_virtio_net(vdev);
448
449 qemu_flush_queued_packets(&n->nic->nc);
450
451 /* We now have RX buffers, signal to the IO thread to break out of the
452 * select to re-poll the tap file descriptor */
453 qemu_notify_event();
454 }
455
456 static int virtio_net_can_receive(VLANClientState *nc)
457 {
458 VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
459 if (!n->vdev.vm_running) {
460 return 0;
461 }
462
463 if (!virtio_queue_ready(n->rx_vq) ||
464 !(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
465 return 0;
466
467 return 1;
468 }
469
470 static int virtio_net_has_buffers(VirtIONet *n, int bufsize)
471 {
472 if (virtio_queue_empty(n->rx_vq) ||
473 (n->mergeable_rx_bufs &&
474 !virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
475 virtio_queue_set_notification(n->rx_vq, 1);
476
477 /* To avoid a race condition where the guest has made some buffers
478 * available after the above check but before notification was
479 * enabled, check for available buffers again.
480 */
481 if (virtio_queue_empty(n->rx_vq) ||
482 (n->mergeable_rx_bufs &&
483 !virtqueue_avail_bytes(n->rx_vq, bufsize, 0)))
484 return 0;
485 }
486
487 virtio_queue_set_notification(n->rx_vq, 0);
488 return 1;
489 }
490
491 /* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
492 * it never finds out that the packets don't have valid checksums. This
493 * causes dhclient to get upset. Fedora's carried a patch for ages to
494 * fix this with Xen but it hasn't appeared in an upstream release of
495 * dhclient yet.
496 *
497 * To avoid breaking existing guests, we catch udp packets and add
498 * checksums. This is terrible but it's better than hacking the guest
499 * kernels.
500 *
501 * N.B. if we introduce a zero-copy API, this operation is no longer free so
502 * we should provide a mechanism to disable it to avoid polluting the host
503 * cache.
504 */
505 static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
506 const uint8_t *buf, size_t size)
507 {
508 if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
509 (size > 27 && size < 1500) && /* normal sized MTU */
510 (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
511 (buf[23] == 17) && /* ip.protocol == UDP */
512 (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
513 /* FIXME this cast is evil */
514 net_checksum_calculate((uint8_t *)buf, size);
515 hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
516 }
517 }
518
519 static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
520 const void *buf, size_t size, size_t hdr_len)
521 {
522 struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)iov[0].iov_base;
523 int offset = 0;
524
525 hdr->flags = 0;
526 hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
527
528 if (n->has_vnet_hdr) {
529 memcpy(hdr, buf, sizeof(*hdr));
530 offset = sizeof(*hdr);
531 work_around_broken_dhclient(hdr, buf + offset, size - offset);
532 }
533
534 /* We only ever receive a struct virtio_net_hdr from the tapfd,
535 * but we may be passing along a larger header to the guest.
536 */
537 iov[0].iov_base += hdr_len;
538 iov[0].iov_len -= hdr_len;
539
540 return offset;
541 }
542
543 static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
544 {
545 static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
546 static const uint8_t vlan[] = {0x81, 0x00};
547 uint8_t *ptr = (uint8_t *)buf;
548 int i;
549
550 if (n->promisc)
551 return 1;
552
553 if (n->has_vnet_hdr) {
554 ptr += sizeof(struct virtio_net_hdr);
555 }
556
557 if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
558 int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff;
559 if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
560 return 0;
561 }
562
563 if (ptr[0] & 1) { // multicast
564 if (!memcmp(ptr, bcast, sizeof(bcast))) {
565 return !n->nobcast;
566 } else if (n->nomulti) {
567 return 0;
568 } else if (n->allmulti || n->mac_table.multi_overflow) {
569 return 1;
570 }
571
572 for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
573 if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
574 return 1;
575 }
576 }
577 } else { // unicast
578 if (n->nouni) {
579 return 0;
580 } else if (n->alluni || n->mac_table.uni_overflow) {
581 return 1;
582 } else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
583 return 1;
584 }
585
586 for (i = 0; i < n->mac_table.first_multi; i++) {
587 if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
588 return 1;
589 }
590 }
591 }
592
593 return 0;
594 }
595
596 static ssize_t virtio_net_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
597 {
598 VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
599 struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL;
600 size_t guest_hdr_len, offset, i, host_hdr_len;
601
602 if (!virtio_net_can_receive(&n->nic->nc))
603 return -1;
604
605 /* hdr_len refers to the header we supply to the guest */
606 guest_hdr_len = n->mergeable_rx_bufs ?
607 sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
608
609
610 host_hdr_len = n->has_vnet_hdr ? sizeof(struct virtio_net_hdr) : 0;
611 if (!virtio_net_has_buffers(n, size + guest_hdr_len - host_hdr_len))
612 return 0;
613
614 if (!receive_filter(n, buf, size))
615 return size;
616
617 offset = i = 0;
618
619 while (offset < size) {
620 VirtQueueElement elem;
621 int len, total;
622 struct iovec sg[VIRTQUEUE_MAX_SIZE];
623
624 total = 0;
625
626 if (virtqueue_pop(n->rx_vq, &elem) == 0) {
627 if (i == 0)
628 return -1;
629 error_report("virtio-net unexpected empty queue: "
630 "i %zd mergeable %d offset %zd, size %zd, "
631 "guest hdr len %zd, host hdr len %zd guest features 0x%x",
632 i, n->mergeable_rx_bufs, offset, size,
633 guest_hdr_len, host_hdr_len, n->vdev.guest_features);
634 exit(1);
635 }
636
637 if (elem.in_num < 1) {
638 error_report("virtio-net receive queue contains no in buffers");
639 exit(1);
640 }
641
642 if (!n->mergeable_rx_bufs && elem.in_sg[0].iov_len != guest_hdr_len) {
643 error_report("virtio-net header not in first element");
644 exit(1);
645 }
646
647 memcpy(&sg, &elem.in_sg[0], sizeof(sg[0]) * elem.in_num);
648
649 if (i == 0) {
650 if (n->mergeable_rx_bufs)
651 mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base;
652
653 offset += receive_header(n, sg, elem.in_num,
654 buf + offset, size - offset, guest_hdr_len);
655 total += guest_hdr_len;
656 }
657
658 /* copy in packet. ugh */
659 len = iov_from_buf(sg, elem.in_num,
660 buf + offset, 0, size - offset);
661 total += len;
662 offset += len;
663 /* If buffers can't be merged, at this point we
664 * must have consumed the complete packet.
665 * Otherwise, drop it. */
666 if (!n->mergeable_rx_bufs && offset < size) {
667 #if 0
668 error_report("virtio-net truncated non-mergeable packet: "
669 "i %zd mergeable %d offset %zd, size %zd, "
670 "guest hdr len %zd, host hdr len %zd",
671 i, n->mergeable_rx_bufs,
672 offset, size, guest_hdr_len, host_hdr_len);
673 #endif
674 return size;
675 }
676
677 /* signal other side */
678 virtqueue_fill(n->rx_vq, &elem, total, i++);
679 }
680
681 if (mhdr) {
682 stw_p(&mhdr->num_buffers, i);
683 }
684
685 virtqueue_flush(n->rx_vq, i);
686 virtio_notify(&n->vdev, n->rx_vq);
687
688 return size;
689 }
690
691 static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq);
692
693 static void virtio_net_tx_complete(VLANClientState *nc, ssize_t len)
694 {
695 VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
696
697 virtqueue_push(n->tx_vq, &n->async_tx.elem, n->async_tx.len);
698 virtio_notify(&n->vdev, n->tx_vq);
699
700 n->async_tx.elem.out_num = n->async_tx.len = 0;
701
702 virtio_queue_set_notification(n->tx_vq, 1);
703 virtio_net_flush_tx(n, n->tx_vq);
704 }
705
706 /* TX */
707 static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
708 {
709 VirtQueueElement elem;
710 int32_t num_packets = 0;
711 if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)) {
712 return num_packets;
713 }
714
715 assert(n->vdev.vm_running);
716
717 if (n->async_tx.elem.out_num) {
718 virtio_queue_set_notification(n->tx_vq, 0);
719 return num_packets;
720 }
721
722 while (virtqueue_pop(vq, &elem)) {
723 ssize_t ret, len = 0;
724 unsigned int out_num = elem.out_num;
725 struct iovec *out_sg = &elem.out_sg[0];
726 unsigned hdr_len;
727
728 /* hdr_len refers to the header received from the guest */
729 hdr_len = n->mergeable_rx_bufs ?
730 sizeof(struct virtio_net_hdr_mrg_rxbuf) :
731 sizeof(struct virtio_net_hdr);
732
733 if (out_num < 1 || out_sg->iov_len != hdr_len) {
734 error_report("virtio-net header not in first element");
735 exit(1);
736 }
737
738 /* ignore the header if GSO is not supported */
739 if (!n->has_vnet_hdr) {
740 out_num--;
741 out_sg++;
742 len += hdr_len;
743 } else if (n->mergeable_rx_bufs) {
744 /* tapfd expects a struct virtio_net_hdr */
745 hdr_len -= sizeof(struct virtio_net_hdr);
746 out_sg->iov_len -= hdr_len;
747 len += hdr_len;
748 }
749
750 ret = qemu_sendv_packet_async(&n->nic->nc, out_sg, out_num,
751 virtio_net_tx_complete);
752 if (ret == 0) {
753 virtio_queue_set_notification(n->tx_vq, 0);
754 n->async_tx.elem = elem;
755 n->async_tx.len = len;
756 return -EBUSY;
757 }
758
759 len += ret;
760
761 virtqueue_push(vq, &elem, len);
762 virtio_notify(&n->vdev, vq);
763
764 if (++num_packets >= n->tx_burst) {
765 break;
766 }
767 }
768 return num_packets;
769 }
770
771 static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
772 {
773 VirtIONet *n = to_virtio_net(vdev);
774
775 /* This happens when device was stopped but VCPU wasn't. */
776 if (!n->vdev.vm_running) {
777 n->tx_waiting = 1;
778 return;
779 }
780
781 if (n->tx_waiting) {
782 virtio_queue_set_notification(vq, 1);
783 qemu_del_timer(n->tx_timer);
784 n->tx_waiting = 0;
785 virtio_net_flush_tx(n, vq);
786 } else {
787 qemu_mod_timer(n->tx_timer,
788 qemu_get_clock_ns(vm_clock) + n->tx_timeout);
789 n->tx_waiting = 1;
790 virtio_queue_set_notification(vq, 0);
791 }
792 }
793
794 static void virtio_net_handle_tx_bh(VirtIODevice *vdev, VirtQueue *vq)
795 {
796 VirtIONet *n = to_virtio_net(vdev);
797
798 if (unlikely(n->tx_waiting)) {
799 return;
800 }
801 n->tx_waiting = 1;
802 /* This happens when device was stopped but VCPU wasn't. */
803 if (!n->vdev.vm_running) {
804 return;
805 }
806 virtio_queue_set_notification(vq, 0);
807 qemu_bh_schedule(n->tx_bh);
808 }
809
810 static void virtio_net_tx_timer(void *opaque)
811 {
812 VirtIONet *n = opaque;
813 assert(n->vdev.vm_running);
814
815 n->tx_waiting = 0;
816
817 /* Just in case the driver is not ready on more */
818 if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
819 return;
820
821 virtio_queue_set_notification(n->tx_vq, 1);
822 virtio_net_flush_tx(n, n->tx_vq);
823 }
824
825 static void virtio_net_tx_bh(void *opaque)
826 {
827 VirtIONet *n = opaque;
828 int32_t ret;
829
830 assert(n->vdev.vm_running);
831
832 n->tx_waiting = 0;
833
834 /* Just in case the driver is not ready on more */
835 if (unlikely(!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)))
836 return;
837
838 ret = virtio_net_flush_tx(n, n->tx_vq);
839 if (ret == -EBUSY) {
840 return; /* Notification re-enable handled by tx_complete */
841 }
842
843 /* If we flush a full burst of packets, assume there are
844 * more coming and immediately reschedule */
845 if (ret >= n->tx_burst) {
846 qemu_bh_schedule(n->tx_bh);
847 n->tx_waiting = 1;
848 return;
849 }
850
851 /* If less than a full burst, re-enable notification and flush
852 * anything that may have come in while we weren't looking. If
853 * we find something, assume the guest is still active and reschedule */
854 virtio_queue_set_notification(n->tx_vq, 1);
855 if (virtio_net_flush_tx(n, n->tx_vq) > 0) {
856 virtio_queue_set_notification(n->tx_vq, 0);
857 qemu_bh_schedule(n->tx_bh);
858 n->tx_waiting = 1;
859 }
860 }
861
862 static void virtio_net_save(QEMUFile *f, void *opaque)
863 {
864 VirtIONet *n = opaque;
865
866 /* At this point, backend must be stopped, otherwise
867 * it might keep writing to memory. */
868 assert(!n->vhost_started);
869 virtio_save(&n->vdev, f);
870
871 qemu_put_buffer(f, n->mac, ETH_ALEN);
872 qemu_put_be32(f, n->tx_waiting);
873 qemu_put_be32(f, n->mergeable_rx_bufs);
874 qemu_put_be16(f, n->status);
875 qemu_put_byte(f, n->promisc);
876 qemu_put_byte(f, n->allmulti);
877 qemu_put_be32(f, n->mac_table.in_use);
878 qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
879 qemu_put_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
880 qemu_put_be32(f, n->has_vnet_hdr);
881 qemu_put_byte(f, n->mac_table.multi_overflow);
882 qemu_put_byte(f, n->mac_table.uni_overflow);
883 qemu_put_byte(f, n->alluni);
884 qemu_put_byte(f, n->nomulti);
885 qemu_put_byte(f, n->nouni);
886 qemu_put_byte(f, n->nobcast);
887 qemu_put_byte(f, n->has_ufo);
888 }
889
890 static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
891 {
892 VirtIONet *n = opaque;
893 int i;
894
895 if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
896 return -EINVAL;
897
898 virtio_load(&n->vdev, f);
899
900 qemu_get_buffer(f, n->mac, ETH_ALEN);
901 n->tx_waiting = qemu_get_be32(f);
902 n->mergeable_rx_bufs = qemu_get_be32(f);
903
904 if (version_id >= 3)
905 n->status = qemu_get_be16(f);
906
907 if (version_id >= 4) {
908 if (version_id < 8) {
909 n->promisc = qemu_get_be32(f);
910 n->allmulti = qemu_get_be32(f);
911 } else {
912 n->promisc = qemu_get_byte(f);
913 n->allmulti = qemu_get_byte(f);
914 }
915 }
916
917 if (version_id >= 5) {
918 n->mac_table.in_use = qemu_get_be32(f);
919 /* MAC_TABLE_ENTRIES may be different from the saved image */
920 if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
921 qemu_get_buffer(f, n->mac_table.macs,
922 n->mac_table.in_use * ETH_ALEN);
923 } else if (n->mac_table.in_use) {
924 qemu_fseek(f, n->mac_table.in_use * ETH_ALEN, SEEK_CUR);
925 n->mac_table.multi_overflow = n->mac_table.uni_overflow = 1;
926 n->mac_table.in_use = 0;
927 }
928 }
929
930 if (version_id >= 6)
931 qemu_get_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
932
933 if (version_id >= 7) {
934 if (qemu_get_be32(f) && !peer_has_vnet_hdr(n)) {
935 error_report("virtio-net: saved image requires vnet_hdr=on");
936 return -1;
937 }
938
939 if (n->has_vnet_hdr) {
940 tap_using_vnet_hdr(n->nic->nc.peer, 1);
941 tap_set_offload(n->nic->nc.peer,
942 (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
943 (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
944 (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
945 (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_ECN) & 1,
946 (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_UFO) & 1);
947 }
948 }
949
950 if (version_id >= 9) {
951 n->mac_table.multi_overflow = qemu_get_byte(f);
952 n->mac_table.uni_overflow = qemu_get_byte(f);
953 }
954
955 if (version_id >= 10) {
956 n->alluni = qemu_get_byte(f);
957 n->nomulti = qemu_get_byte(f);
958 n->nouni = qemu_get_byte(f);
959 n->nobcast = qemu_get_byte(f);
960 }
961
962 if (version_id >= 11) {
963 if (qemu_get_byte(f) && !peer_has_ufo(n)) {
964 error_report("virtio-net: saved image requires TUN_F_UFO support");
965 return -1;
966 }
967 }
968
969 /* Find the first multicast entry in the saved MAC filter */
970 for (i = 0; i < n->mac_table.in_use; i++) {
971 if (n->mac_table.macs[i * ETH_ALEN] & 1) {
972 break;
973 }
974 }
975 n->mac_table.first_multi = i;
976 return 0;
977 }
978
979 static void virtio_net_cleanup(VLANClientState *nc)
980 {
981 VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
982
983 n->nic = NULL;
984 }
985
986 static NetClientInfo net_virtio_info = {
987 .type = NET_CLIENT_TYPE_NIC,
988 .size = sizeof(NICState),
989 .can_receive = virtio_net_can_receive,
990 .receive = virtio_net_receive,
991 .cleanup = virtio_net_cleanup,
992 .link_status_changed = virtio_net_set_link_status,
993 };
994
995 VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
996 virtio_net_conf *net)
997 {
998 VirtIONet *n;
999
1000 n = (VirtIONet *)virtio_common_init("virtio-net", VIRTIO_ID_NET,
1001 sizeof(struct virtio_net_config),
1002 sizeof(VirtIONet));
1003
1004 n->vdev.get_config = virtio_net_get_config;
1005 n->vdev.set_config = virtio_net_set_config;
1006 n->vdev.get_features = virtio_net_get_features;
1007 n->vdev.set_features = virtio_net_set_features;
1008 n->vdev.bad_features = virtio_net_bad_features;
1009 n->vdev.reset = virtio_net_reset;
1010 n->vdev.set_status = virtio_net_set_status;
1011 n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
1012
1013 if (net->tx && strcmp(net->tx, "timer") && strcmp(net->tx, "bh")) {
1014 error_report("virtio-net: "
1015 "Unknown option tx=%s, valid options: \"timer\" \"bh\"",
1016 net->tx);
1017 error_report("Defaulting to \"bh\"");
1018 }
1019
1020 if (net->tx && !strcmp(net->tx, "timer")) {
1021 n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx_timer);
1022 n->tx_timer = qemu_new_timer_ns(vm_clock, virtio_net_tx_timer, n);
1023 n->tx_timeout = net->txtimer;
1024 } else {
1025 n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx_bh);
1026 n->tx_bh = qemu_bh_new(virtio_net_tx_bh, n);
1027 }
1028 n->ctrl_vq = virtio_add_queue(&n->vdev, 64, virtio_net_handle_ctrl);
1029 qemu_macaddr_default_if_unset(&conf->macaddr);
1030 memcpy(&n->mac[0], &conf->macaddr, sizeof(n->mac));
1031 n->status = VIRTIO_NET_S_LINK_UP;
1032
1033 n->nic = qemu_new_nic(&net_virtio_info, conf, object_get_typename(OBJECT(dev)), dev->id, n);
1034
1035 qemu_format_nic_info_str(&n->nic->nc, conf->macaddr.a);
1036
1037 n->tx_waiting = 0;
1038 n->tx_burst = net->txburst;
1039 n->mergeable_rx_bufs = 0;
1040 n->promisc = 1; /* for compatibility */
1041
1042 n->mac_table.macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN);
1043
1044 n->vlans = g_malloc0(MAX_VLAN >> 3);
1045
1046 n->qdev = dev;
1047 register_savevm(dev, "virtio-net", -1, VIRTIO_NET_VM_VERSION,
1048 virtio_net_save, virtio_net_load, n);
1049
1050 add_boot_device_path(conf->bootindex, dev, "/ethernet-phy@0");
1051
1052 return &n->vdev;
1053 }
1054
1055 void virtio_net_exit(VirtIODevice *vdev)
1056 {
1057 VirtIONet *n = DO_UPCAST(VirtIONet, vdev, vdev);
1058
1059 /* This will stop vhost backend if appropriate. */
1060 virtio_net_set_status(vdev, 0);
1061
1062 qemu_purge_queued_packets(&n->nic->nc);
1063
1064 unregister_savevm(n->qdev, "virtio-net", n);
1065
1066 g_free(n->mac_table.macs);
1067 g_free(n->vlans);
1068
1069 if (n->tx_timer) {
1070 qemu_del_timer(n->tx_timer);
1071 qemu_free_timer(n->tx_timer);
1072 } else {
1073 qemu_bh_delete(n->tx_bh);
1074 }
1075
1076 qemu_del_vlan_client(&n->nic->nc);
1077 virtio_cleanup(&n->vdev);
1078 }