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Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[linux-2.6/mini2440.git] / drivers / net / virtio_net.c
blob4d1d47953fc6e4d780c538b5ffd00c901ffc06bf
1 /* A simple network driver using virtio.
2 *
3 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19 //#define DEBUG
20 #include <linux/netdevice.h>
21 #include <linux/etherdevice.h>
22 #include <linux/ethtool.h>
23 #include <linux/module.h>
24 #include <linux/virtio.h>
25 #include <linux/virtio_net.h>
26 #include <linux/scatterlist.h>
27 #include <linux/if_vlan.h>
28
29 static int napi_weight = 128;
30 module_param(napi_weight, int, 0444);
31
32 static int csum = 1, gso = 1;
33 module_param(csum, bool, 0444);
34 module_param(gso, bool, 0444);
35
36 /* FIXME: MTU in config. */
37 #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
38 #define GOOD_COPY_LEN 128
39
40 #define VIRTNET_SEND_COMMAND_SG_MAX 2
41
42 struct virtnet_info
43 {
44 struct virtio_device *vdev;
45 struct virtqueue *rvq, *svq, *cvq;
46 struct net_device *dev;
47 struct napi_struct napi;
48 unsigned int status;
49
50 /* The skb we couldn't send because buffers were full. */
51 struct sk_buff *last_xmit_skb;
52
53 /* If we need to free in a timer, this is it. */
54 struct timer_list xmit_free_timer;
55
56 /* Number of input buffers, and max we've ever had. */
57 unsigned int num, max;
58
59 /* For cleaning up after transmission. */
60 struct tasklet_struct tasklet;
61 bool free_in_tasklet;
62
63 /* I like... big packets and I cannot lie! */
64 bool big_packets;
65
66 /* Host will merge rx buffers for big packets (shake it! shake it!) */
67 bool mergeable_rx_bufs;
68
69 /* Receive & send queues. */
70 struct sk_buff_head recv;
71 struct sk_buff_head send;
72
73 /* Chain pages by the private ptr. */
74 struct page *pages;
75 };
76
77 static inline void *skb_vnet_hdr(struct sk_buff *skb)
78 {
79 return (struct virtio_net_hdr *)skb->cb;
80 }
81
82 static void give_a_page(struct virtnet_info *vi, struct page *page)
83 {
84 page->private = (unsigned long)vi->pages;
85 vi->pages = page;
86 }
87
88 static void trim_pages(struct virtnet_info *vi, struct sk_buff *skb)
89 {
90 unsigned int i;
91
92 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
93 give_a_page(vi, skb_shinfo(skb)->frags[i].page);
94 skb_shinfo(skb)->nr_frags = 0;
95 skb->data_len = 0;
96 }
97
98 static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
99 {
100 struct page *p = vi->pages;
101
102 if (p)
103 vi->pages = (struct page *)p->private;
104 else
105 p = alloc_page(gfp_mask);
106 return p;
107 }
108
109 static void skb_xmit_done(struct virtqueue *svq)
110 {
111 struct virtnet_info *vi = svq->vdev->priv;
112
113 /* Suppress further interrupts. */
114 svq->vq_ops->disable_cb(svq);
115
116 /* We were probably waiting for more output buffers. */
117 netif_wake_queue(vi->dev);
118
119 /* Make sure we re-xmit last_xmit_skb: if there are no more packets
120 * queued, start_xmit won't be called. */
121 tasklet_schedule(&vi->tasklet);
122 }
123
124 static void receive_skb(struct net_device *dev, struct sk_buff *skb,
125 unsigned len)
126 {
127 struct virtnet_info *vi = netdev_priv(dev);
128 struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
129 int err;
130 int i;
131
132 if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
133 pr_debug("%s: short packet %i\n", dev->name, len);
134 dev->stats.rx_length_errors++;
135 goto drop;
136 }
137
138 if (vi->mergeable_rx_bufs) {
139 struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
140 unsigned int copy;
141 char *p = page_address(skb_shinfo(skb)->frags[0].page);
142
143 if (len > PAGE_SIZE)
144 len = PAGE_SIZE;
145 len -= sizeof(struct virtio_net_hdr_mrg_rxbuf);
146
147 memcpy(hdr, p, sizeof(*mhdr));
148 p += sizeof(*mhdr);
149
150 copy = len;
151 if (copy > skb_tailroom(skb))
152 copy = skb_tailroom(skb);
153
154 memcpy(skb_put(skb, copy), p, copy);
155
156 len -= copy;
157
158 if (!len) {
159 give_a_page(vi, skb_shinfo(skb)->frags[0].page);
160 skb_shinfo(skb)->nr_frags--;
161 } else {
162 skb_shinfo(skb)->frags[0].page_offset +=
163 sizeof(*mhdr) + copy;
164 skb_shinfo(skb)->frags[0].size = len;
165 skb->data_len += len;
166 skb->len += len;
167 }
168
169 while (--mhdr->num_buffers) {
170 struct sk_buff *nskb;
171
172 i = skb_shinfo(skb)->nr_frags;
173 if (i >= MAX_SKB_FRAGS) {
174 pr_debug("%s: packet too long %d\n", dev->name,
175 len);
176 dev->stats.rx_length_errors++;
177 goto drop;
178 }
179
180 nskb = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
181 if (!nskb) {
182 pr_debug("%s: rx error: %d buffers missing\n",
183 dev->name, mhdr->num_buffers);
184 dev->stats.rx_length_errors++;
185 goto drop;
186 }
187
188 __skb_unlink(nskb, &vi->recv);
189 vi->num--;
190
191 skb_shinfo(skb)->frags[i] = skb_shinfo(nskb)->frags[0];
192 skb_shinfo(nskb)->nr_frags = 0;
193 kfree_skb(nskb);
194
195 if (len > PAGE_SIZE)
196 len = PAGE_SIZE;
197
198 skb_shinfo(skb)->frags[i].size = len;
199 skb_shinfo(skb)->nr_frags++;
200 skb->data_len += len;
201 skb->len += len;
202 }
203 } else {
204 len -= sizeof(struct virtio_net_hdr);
205
206 if (len <= MAX_PACKET_LEN)
207 trim_pages(vi, skb);
208
209 err = pskb_trim(skb, len);
210 if (err) {
211 pr_debug("%s: pskb_trim failed %i %d\n", dev->name,
212 len, err);
213 dev->stats.rx_dropped++;
214 goto drop;
215 }
216 }
217
218 skb->truesize += skb->data_len;
219 dev->stats.rx_bytes += skb->len;
220 dev->stats.rx_packets++;
221
222 if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
223 pr_debug("Needs csum!\n");
224 if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset))
225 goto frame_err;
226 }
227
228 skb->protocol = eth_type_trans(skb, dev);
229 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
230 ntohs(skb->protocol), skb->len, skb->pkt_type);
231
232 if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
233 pr_debug("GSO!\n");
234 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
235 case VIRTIO_NET_HDR_GSO_TCPV4:
236 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
237 break;
238 case VIRTIO_NET_HDR_GSO_UDP:
239 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
240 break;
241 case VIRTIO_NET_HDR_GSO_TCPV6:
242 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
243 break;
244 default:
245 if (net_ratelimit())
246 printk(KERN_WARNING "%s: bad gso type %u.\n",
247 dev->name, hdr->gso_type);
248 goto frame_err;
249 }
250
251 if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
252 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
253
254 skb_shinfo(skb)->gso_size = hdr->gso_size;
255 if (skb_shinfo(skb)->gso_size == 0) {
256 if (net_ratelimit())
257 printk(KERN_WARNING "%s: zero gso size.\n",
258 dev->name);
259 goto frame_err;
260 }
261
262 /* Header must be checked, and gso_segs computed. */
263 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
264 skb_shinfo(skb)->gso_segs = 0;
265 }
266
267 netif_receive_skb(skb);
268 return;
269
270 frame_err:
271 dev->stats.rx_frame_errors++;
272 drop:
273 dev_kfree_skb(skb);
274 }
275
276 static void try_fill_recv_maxbufs(struct virtnet_info *vi)
277 {
278 struct sk_buff *skb;
279 struct scatterlist sg[2+MAX_SKB_FRAGS];
280 int num, err, i;
281
282 sg_init_table(sg, 2+MAX_SKB_FRAGS);
283 for (;;) {
284 struct virtio_net_hdr *hdr;
285
286 skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
287 if (unlikely(!skb))
288 break;
289
290 skb_put(skb, MAX_PACKET_LEN);
291
292 hdr = skb_vnet_hdr(skb);
293 sg_set_buf(sg, hdr, sizeof(*hdr));
294
295 if (vi->big_packets) {
296 for (i = 0; i < MAX_SKB_FRAGS; i++) {
297 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
298 f->page = get_a_page(vi, GFP_ATOMIC);
299 if (!f->page)
300 break;
301
302 f->page_offset = 0;
303 f->size = PAGE_SIZE;
304
305 skb->data_len += PAGE_SIZE;
306 skb->len += PAGE_SIZE;
307
308 skb_shinfo(skb)->nr_frags++;
309 }
310 }
311
312 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
313 skb_queue_head(&vi->recv, skb);
314
315 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
316 if (err) {
317 skb_unlink(skb, &vi->recv);
318 trim_pages(vi, skb);
319 kfree_skb(skb);
320 break;
321 }
322 vi->num++;
323 }
324 if (unlikely(vi->num > vi->max))
325 vi->max = vi->num;
326 vi->rvq->vq_ops->kick(vi->rvq);
327 }
328
329 static void try_fill_recv(struct virtnet_info *vi)
330 {
331 struct sk_buff *skb;
332 struct scatterlist sg[1];
333 int err;
334
335 if (!vi->mergeable_rx_bufs) {
336 try_fill_recv_maxbufs(vi);
337 return;
338 }
339
340 for (;;) {
341 skb_frag_t *f;
342
343 skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN);
344 if (unlikely(!skb))
345 break;
346
347 skb_reserve(skb, NET_IP_ALIGN);
348
349 f = &skb_shinfo(skb)->frags[0];
350 f->page = get_a_page(vi, GFP_ATOMIC);
351 if (!f->page) {
352 kfree_skb(skb);
353 break;
354 }
355
356 f->page_offset = 0;
357 f->size = PAGE_SIZE;
358
359 skb_shinfo(skb)->nr_frags++;
360
361 sg_init_one(sg, page_address(f->page), PAGE_SIZE);
362 skb_queue_head(&vi->recv, skb);
363
364 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb);
365 if (err) {
366 skb_unlink(skb, &vi->recv);
367 kfree_skb(skb);
368 break;
369 }
370 vi->num++;
371 }
372 if (unlikely(vi->num > vi->max))
373 vi->max = vi->num;
374 vi->rvq->vq_ops->kick(vi->rvq);
375 }
376
377 static void skb_recv_done(struct virtqueue *rvq)
378 {
379 struct virtnet_info *vi = rvq->vdev->priv;
380 /* Schedule NAPI, Suppress further interrupts if successful. */
381 if (napi_schedule_prep(&vi->napi)) {
382 rvq->vq_ops->disable_cb(rvq);
383 __napi_schedule(&vi->napi);
384 }
385 }
386
387 static int virtnet_poll(struct napi_struct *napi, int budget)
388 {
389 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
390 struct sk_buff *skb = NULL;
391 unsigned int len, received = 0;
392
393 again:
394 while (received < budget &&
395 (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
396 __skb_unlink(skb, &vi->recv);
397 receive_skb(vi->dev, skb, len);
398 vi->num--;
399 received++;
400 }
401
402 /* FIXME: If we oom and completely run out of inbufs, we need
403 * to start a timer trying to fill more. */
404 if (vi->num < vi->max / 2)
405 try_fill_recv(vi);
406
407 /* Out of packets? */
408 if (received < budget) {
409 napi_complete(napi);
410 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
411 && napi_schedule_prep(napi)) {
412 vi->rvq->vq_ops->disable_cb(vi->rvq);
413 __napi_schedule(napi);
414 goto again;
415 }
416 }
417
418 return received;
419 }
420
421 static void free_old_xmit_skbs(struct virtnet_info *vi)
422 {
423 struct sk_buff *skb;
424 unsigned int len;
425
426 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
427 pr_debug("Sent skb %p\n", skb);
428 __skb_unlink(skb, &vi->send);
429 vi->dev->stats.tx_bytes += skb->len;
430 vi->dev->stats.tx_packets++;
431 kfree_skb(skb);
432 }
433 }
434
435 /* If the virtio transport doesn't always notify us when all in-flight packets
436 * are consumed, we fall back to using this function on a timer to free them. */
437 static void xmit_free(unsigned long data)
438 {
439 struct virtnet_info *vi = (void *)data;
440
441 netif_tx_lock(vi->dev);
442
443 free_old_xmit_skbs(vi);
444
445 if (!skb_queue_empty(&vi->send))
446 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
447
448 netif_tx_unlock(vi->dev);
449 }
450
451 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
452 {
453 int num, err;
454 struct scatterlist sg[2+MAX_SKB_FRAGS];
455 struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
456 struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
457 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
458
459 sg_init_table(sg, 2+MAX_SKB_FRAGS);
460
461 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
462
463 if (skb->ip_summed == CHECKSUM_PARTIAL) {
464 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
465 hdr->csum_start = skb->csum_start - skb_headroom(skb);
466 hdr->csum_offset = skb->csum_offset;
467 } else {
468 hdr->flags = 0;
469 hdr->csum_offset = hdr->csum_start = 0;
470 }
471
472 if (skb_is_gso(skb)) {
473 hdr->hdr_len = skb_transport_header(skb) - skb->data;
474 hdr->gso_size = skb_shinfo(skb)->gso_size;
475 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
476 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
477 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
478 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
479 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
480 hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
481 else
482 BUG();
483 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
484 hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
485 } else {
486 hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
487 hdr->gso_size = hdr->hdr_len = 0;
488 }
489
490 mhdr->num_buffers = 0;
491
492 /* Encode metadata header at front. */
493 if (vi->mergeable_rx_bufs)
494 sg_set_buf(sg, mhdr, sizeof(*mhdr));
495 else
496 sg_set_buf(sg, hdr, sizeof(*hdr));
497
498 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
499
500 err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
501 if (!err && !vi->free_in_tasklet)
502 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
503
504 return err;
505 }
506
507 static void xmit_tasklet(unsigned long data)
508 {
509 struct virtnet_info *vi = (void *)data;
510
511 netif_tx_lock_bh(vi->dev);
512 if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) {
513 vi->svq->vq_ops->kick(vi->svq);
514 vi->last_xmit_skb = NULL;
515 }
516 if (vi->free_in_tasklet)
517 free_old_xmit_skbs(vi);
518 netif_tx_unlock_bh(vi->dev);
519 }
520
521 static int start_xmit(struct sk_buff *skb, struct net_device *dev)
522 {
523 struct virtnet_info *vi = netdev_priv(dev);
524
525 again:
526 /* Free up any pending old buffers before queueing new ones. */
527 free_old_xmit_skbs(vi);
528
529 /* If we has a buffer left over from last time, send it now. */
530 if (unlikely(vi->last_xmit_skb) &&
531 xmit_skb(vi, vi->last_xmit_skb) != 0)
532 goto stop_queue;
533
534 vi->last_xmit_skb = NULL;
535
536 /* Put new one in send queue and do transmit */
537 if (likely(skb)) {
538 __skb_queue_head(&vi->send, skb);
539 if (xmit_skb(vi, skb) != 0) {
540 vi->last_xmit_skb = skb;
541 skb = NULL;
542 goto stop_queue;
543 }
544 }
545 done:
546 vi->svq->vq_ops->kick(vi->svq);
547 return NETDEV_TX_OK;
548
549 stop_queue:
550 pr_debug("%s: virtio not prepared to send\n", dev->name);
551 netif_stop_queue(dev);
552
553 /* Activate callback for using skbs: if this returns false it
554 * means some were used in the meantime. */
555 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
556 vi->svq->vq_ops->disable_cb(vi->svq);
557 netif_start_queue(dev);
558 goto again;
559 }
560 if (skb) {
561 /* Drop this skb: we only queue one. */
562 vi->dev->stats.tx_dropped++;
563 kfree_skb(skb);
564 }
565 goto done;
566 }
567
568 static int virtnet_set_mac_address(struct net_device *dev, void *p)
569 {
570 struct virtnet_info *vi = netdev_priv(dev);
571 struct virtio_device *vdev = vi->vdev;
572 int ret;
573
574 ret = eth_mac_addr(dev, p);
575 if (ret)
576 return ret;
577
578 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
579 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
580 dev->dev_addr, dev->addr_len);
581
582 return 0;
583 }
584
585 #ifdef CONFIG_NET_POLL_CONTROLLER
586 static void virtnet_netpoll(struct net_device *dev)
587 {
588 struct virtnet_info *vi = netdev_priv(dev);
589
590 napi_schedule(&vi->napi);
591 }
592 #endif
593
594 static int virtnet_open(struct net_device *dev)
595 {
596 struct virtnet_info *vi = netdev_priv(dev);
597
598 napi_enable(&vi->napi);
599
600 /* If all buffers were filled by other side before we napi_enabled, we
601 * won't get another interrupt, so process any outstanding packets
602 * now. virtnet_poll wants re-enable the queue, so we disable here.
603 * We synchronize against interrupts via NAPI_STATE_SCHED */
604 if (napi_schedule_prep(&vi->napi)) {
605 vi->rvq->vq_ops->disable_cb(vi->rvq);
606 __napi_schedule(&vi->napi);
607 }
608 return 0;
609 }
610
611 /*
612 * Send command via the control virtqueue and check status. Commands
613 * supported by the hypervisor, as indicated by feature bits, should
614 * never fail unless improperly formated.
615 */
616 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
617 struct scatterlist *data, int out, int in)
618 {
619 struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
620 struct virtio_net_ctrl_hdr ctrl;
621 virtio_net_ctrl_ack status = ~0;
622 unsigned int tmp;
623 int i;
624
625 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
626 BUG(); /* Caller should know better */
627 return false;
628 }
629
630 BUG_ON(out + in > VIRTNET_SEND_COMMAND_SG_MAX);
631
632 out++; /* Add header */
633 in++; /* Add return status */
634
635 ctrl.class = class;
636 ctrl.cmd = cmd;
637
638 sg_init_table(sg, out + in);
639
640 sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
641 for_each_sg(data, s, out + in - 2, i)
642 sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
643 sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
644
645 if (vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) != 0)
646 BUG();
647
648 vi->cvq->vq_ops->kick(vi->cvq);
649
650 /*
651 * Spin for a response, the kick causes an ioport write, trapping
652 * into the hypervisor, so the request should be handled immediately.
653 */
654 while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp))
655 cpu_relax();
656
657 return status == VIRTIO_NET_OK;
658 }
659
660 static int virtnet_close(struct net_device *dev)
661 {
662 struct virtnet_info *vi = netdev_priv(dev);
663
664 napi_disable(&vi->napi);
665
666 return 0;
667 }
668
669 static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
670 {
671 struct virtnet_info *vi = netdev_priv(dev);
672 struct virtio_device *vdev = vi->vdev;
673
674 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
675 return -ENOSYS;
676
677 return ethtool_op_set_tx_hw_csum(dev, data);
678 }
679
680 static void virtnet_set_rx_mode(struct net_device *dev)
681 {
682 struct virtnet_info *vi = netdev_priv(dev);
683 struct scatterlist sg[2];
684 u8 promisc, allmulti;
685 struct virtio_net_ctrl_mac *mac_data;
686 struct dev_addr_list *addr;
687 void *buf;
688 int i;
689
690 /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
691 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
692 return;
693
694 promisc = ((dev->flags & IFF_PROMISC) != 0);
695 allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
696
697 sg_init_one(sg, &promisc, sizeof(promisc));
698
699 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
700 VIRTIO_NET_CTRL_RX_PROMISC,
701 sg, 1, 0))
702 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
703 promisc ? "en" : "dis");
704
705 sg_init_one(sg, &allmulti, sizeof(allmulti));
706
707 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
708 VIRTIO_NET_CTRL_RX_ALLMULTI,
709 sg, 1, 0))
710 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
711 allmulti ? "en" : "dis");
712
713 /* MAC filter - use one buffer for both lists */
714 mac_data = buf = kzalloc(((dev->uc_count + dev->mc_count) * ETH_ALEN) +
715 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
716 if (!buf) {
717 dev_warn(&dev->dev, "No memory for MAC address buffer\n");
718 return;
719 }
720
721 sg_init_table(sg, 2);
722
723 /* Store the unicast list and count in the front of the buffer */
724 mac_data->entries = dev->uc_count;
725 addr = dev->uc_list;
726 for (i = 0; i < dev->uc_count; i++, addr = addr->next)
727 memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN);
728
729 sg_set_buf(&sg[0], mac_data,
730 sizeof(mac_data->entries) + (dev->uc_count * ETH_ALEN));
731
732 /* multicast list and count fill the end */
733 mac_data = (void *)&mac_data->macs[dev->uc_count][0];
734
735 mac_data->entries = dev->mc_count;
736 addr = dev->mc_list;
737 for (i = 0; i < dev->mc_count; i++, addr = addr->next)
738 memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN);
739
740 sg_set_buf(&sg[1], mac_data,
741 sizeof(mac_data->entries) + (dev->mc_count * ETH_ALEN));
742
743 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
744 VIRTIO_NET_CTRL_MAC_TABLE_SET,
745 sg, 2, 0))
746 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
747
748 kfree(buf);
749 }
750
751 static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
752 {
753 struct virtnet_info *vi = netdev_priv(dev);
754 struct scatterlist sg;
755
756 sg_init_one(&sg, &vid, sizeof(vid));
757
758 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
759 VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
760 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
761 }
762
763 static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
764 {
765 struct virtnet_info *vi = netdev_priv(dev);
766 struct scatterlist sg;
767
768 sg_init_one(&sg, &vid, sizeof(vid));
769
770 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
771 VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
772 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
773 }
774
775 static struct ethtool_ops virtnet_ethtool_ops = {
776 .set_tx_csum = virtnet_set_tx_csum,
777 .set_sg = ethtool_op_set_sg,
778 .set_tso = ethtool_op_set_tso,
779 .get_link = ethtool_op_get_link,
780 };
781
782 #define MIN_MTU 68
783 #define MAX_MTU 65535
784
785 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
786 {
787 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
788 return -EINVAL;
789 dev->mtu = new_mtu;
790 return 0;
791 }
792
793 static const struct net_device_ops virtnet_netdev = {
794 .ndo_open = virtnet_open,
795 .ndo_stop = virtnet_close,
796 .ndo_start_xmit = start_xmit,
797 .ndo_validate_addr = eth_validate_addr,
798 .ndo_set_mac_address = virtnet_set_mac_address,
799 .ndo_set_rx_mode = virtnet_set_rx_mode,
800 .ndo_change_mtu = virtnet_change_mtu,
801 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
802 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
803 #ifdef CONFIG_NET_POLL_CONTROLLER
804 .ndo_poll_controller = virtnet_netpoll,
805 #endif
806 };
807
808 static void virtnet_update_status(struct virtnet_info *vi)
809 {
810 u16 v;
811
812 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS))
813 return;
814
815 vi->vdev->config->get(vi->vdev,
816 offsetof(struct virtio_net_config, status),
817 &v, sizeof(v));
818
819 /* Ignore unknown (future) status bits */
820 v &= VIRTIO_NET_S_LINK_UP;
821
822 if (vi->status == v)
823 return;
824
825 vi->status = v;
826
827 if (vi->status & VIRTIO_NET_S_LINK_UP) {
828 netif_carrier_on(vi->dev);
829 netif_wake_queue(vi->dev);
830 } else {
831 netif_carrier_off(vi->dev);
832 netif_stop_queue(vi->dev);
833 }
834 }
835
836 static void virtnet_config_changed(struct virtio_device *vdev)
837 {
838 struct virtnet_info *vi = vdev->priv;
839
840 virtnet_update_status(vi);
841 }
842
843 static int virtnet_probe(struct virtio_device *vdev)
844 {
845 int err;
846 struct net_device *dev;
847 struct virtnet_info *vi;
848
849 /* Allocate ourselves a network device with room for our info */
850 dev = alloc_etherdev(sizeof(struct virtnet_info));
851 if (!dev)
852 return -ENOMEM;
853
854 /* Set up network device as normal. */
855 dev->netdev_ops = &virtnet_netdev;
856 dev->features = NETIF_F_HIGHDMA;
857 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
858 SET_NETDEV_DEV(dev, &vdev->dev);
859
860 /* Do we support "hardware" checksums? */
861 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
862 /* This opens up the world of extra features. */
863 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
864 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
865 dev->features |= NETIF_F_TSO | NETIF_F_UFO
866 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
867 }
868 /* Individual feature bits: what can host handle? */
869 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
870 dev->features |= NETIF_F_TSO;
871 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
872 dev->features |= NETIF_F_TSO6;
873 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
874 dev->features |= NETIF_F_TSO_ECN;
875 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
876 dev->features |= NETIF_F_UFO;
877 }
878
879 /* Configuration may specify what MAC to use. Otherwise random. */
880 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
881 vdev->config->get(vdev,
882 offsetof(struct virtio_net_config, mac),
883 dev->dev_addr, dev->addr_len);
884 } else
885 random_ether_addr(dev->dev_addr);
886
887 /* Set up our device-specific information */
888 vi = netdev_priv(dev);
889 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
890 vi->dev = dev;
891 vi->vdev = vdev;
892 vdev->priv = vi;
893 vi->pages = NULL;
894
895 /* If they give us a callback when all buffers are done, we don't need
896 * the timer. */
897 vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY);
898
899 /* If we can receive ANY GSO packets, we must allocate large ones. */
900 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4)
901 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)
902 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
903 vi->big_packets = true;
904
905 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
906 vi->mergeable_rx_bufs = true;
907
908 /* We expect two virtqueues, receive then send. */
909 vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
910 if (IS_ERR(vi->rvq)) {
911 err = PTR_ERR(vi->rvq);
912 goto free;
913 }
914
915 vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
916 if (IS_ERR(vi->svq)) {
917 err = PTR_ERR(vi->svq);
918 goto free_recv;
919 }
920
921 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
922 vi->cvq = vdev->config->find_vq(vdev, 2, NULL);
923 if (IS_ERR(vi->cvq)) {
924 err = PTR_ERR(vi->svq);
925 goto free_send;
926 }
927
928 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
929 dev->features |= NETIF_F_HW_VLAN_FILTER;
930 }
931
932 /* Initialize our empty receive and send queues. */
933 skb_queue_head_init(&vi->recv);
934 skb_queue_head_init(&vi->send);
935
936 tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi);
937
938 if (!vi->free_in_tasklet)
939 setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
940
941 err = register_netdev(dev);
942 if (err) {
943 pr_debug("virtio_net: registering device failed\n");
944 goto free_ctrl;
945 }
946
947 /* Last of all, set up some receive buffers. */
948 try_fill_recv(vi);
949
950 /* If we didn't even get one input buffer, we're useless. */
951 if (vi->num == 0) {
952 err = -ENOMEM;
953 goto unregister;
954 }
955
956 vi->status = VIRTIO_NET_S_LINK_UP;
957 virtnet_update_status(vi);
958 netif_carrier_on(dev);
959
960 pr_debug("virtnet: registered device %s\n", dev->name);
961 return 0;
962
963 unregister:
964 unregister_netdev(dev);
965 free_ctrl:
966 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
967 vdev->config->del_vq(vi->cvq);
968 free_send:
969 vdev->config->del_vq(vi->svq);
970 free_recv:
971 vdev->config->del_vq(vi->rvq);
972 free:
973 free_netdev(dev);
974 return err;
975 }
976
977 static void virtnet_remove(struct virtio_device *vdev)
978 {
979 struct virtnet_info *vi = vdev->priv;
980 struct sk_buff *skb;
981
982 /* Stop all the virtqueues. */
983 vdev->config->reset(vdev);
984
985 if (!vi->free_in_tasklet)
986 del_timer_sync(&vi->xmit_free_timer);
987
988 /* Free our skbs in send and recv queues, if any. */
989 while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
990 kfree_skb(skb);
991 vi->num--;
992 }
993 __skb_queue_purge(&vi->send);
994
995 BUG_ON(vi->num != 0);
996
997 vdev->config->del_vq(vi->svq);
998 vdev->config->del_vq(vi->rvq);
999 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
1000 vdev->config->del_vq(vi->cvq);
1001 unregister_netdev(vi->dev);
1002
1003 while (vi->pages)
1004 __free_pages(get_a_page(vi, GFP_KERNEL), 0);
1005
1006 free_netdev(vi->dev);
1007 }
1008
1009 static struct virtio_device_id id_table[] = {
1010 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
1011 { 0 },
1012 };
1013
1014 static unsigned int features[] = {
1015 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
1016 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
1017 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
1018 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
1019 VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */
1020 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
1021 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
1022 VIRTIO_F_NOTIFY_ON_EMPTY,
1023 };
1024
1025 static struct virtio_driver virtio_net = {
1026 .feature_table = features,
1027 .feature_table_size = ARRAY_SIZE(features),
1028 .driver.name = KBUILD_MODNAME,
1029 .driver.owner = THIS_MODULE,
1030 .id_table = id_table,
1031 .probe = virtnet_probe,
1032 .remove = __devexit_p(virtnet_remove),
1033 .config_changed = virtnet_config_changed,
1034 };
1035
1036 static int __init init(void)
1037 {
1038 return register_virtio_driver(&virtio_net);
1039 }
1040
1041 static void __exit fini(void)
1042 {
1043 unregister_virtio_driver(&virtio_net);
1044 }
1045 module_init(init);
1046 module_exit(fini);
1047
1048 MODULE_DEVICE_TABLE(virtio, id_table);
1049 MODULE_DESCRIPTION("Virtio network driver");
1050 MODULE_LICENSE("GPL");
Support for the Chinese Samsung S3C2440 based development boards