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x86, delay: tsc based udelay should have rdtsc_barrier
[linux-2.6/mini2440.git] / drivers / net / virtio_net.c
blob2a6e81d5b579aa9032ae633bb80b6444bcf1ae40
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 + NET_IP_ALIGN);
287 if (unlikely(!skb))
288 break;
289
290 skb_reserve(skb, NET_IP_ALIGN);
291 skb_put(skb, MAX_PACKET_LEN);
292
293 hdr = skb_vnet_hdr(skb);
294 sg_set_buf(sg, hdr, sizeof(*hdr));
295
296 if (vi->big_packets) {
297 for (i = 0; i < MAX_SKB_FRAGS; i++) {
298 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
299 f->page = get_a_page(vi, GFP_ATOMIC);
300 if (!f->page)
301 break;
302
303 f->page_offset = 0;
304 f->size = PAGE_SIZE;
305
306 skb->data_len += PAGE_SIZE;
307 skb->len += PAGE_SIZE;
308
309 skb_shinfo(skb)->nr_frags++;
310 }
311 }
312
313 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
314 skb_queue_head(&vi->recv, skb);
315
316 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
317 if (err) {
318 skb_unlink(skb, &vi->recv);
319 trim_pages(vi, skb);
320 kfree_skb(skb);
321 break;
322 }
323 vi->num++;
324 }
325 if (unlikely(vi->num > vi->max))
326 vi->max = vi->num;
327 vi->rvq->vq_ops->kick(vi->rvq);
328 }
329
330 static void try_fill_recv(struct virtnet_info *vi)
331 {
332 struct sk_buff *skb;
333 struct scatterlist sg[1];
334 int err;
335
336 if (!vi->mergeable_rx_bufs) {
337 try_fill_recv_maxbufs(vi);
338 return;
339 }
340
341 for (;;) {
342 skb_frag_t *f;
343
344 skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN);
345 if (unlikely(!skb))
346 break;
347
348 skb_reserve(skb, NET_IP_ALIGN);
349
350 f = &skb_shinfo(skb)->frags[0];
351 f->page = get_a_page(vi, GFP_ATOMIC);
352 if (!f->page) {
353 kfree_skb(skb);
354 break;
355 }
356
357 f->page_offset = 0;
358 f->size = PAGE_SIZE;
359
360 skb_shinfo(skb)->nr_frags++;
361
362 sg_init_one(sg, page_address(f->page), PAGE_SIZE);
363 skb_queue_head(&vi->recv, skb);
364
365 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb);
366 if (err) {
367 skb_unlink(skb, &vi->recv);
368 kfree_skb(skb);
369 break;
370 }
371 vi->num++;
372 }
373 if (unlikely(vi->num > vi->max))
374 vi->max = vi->num;
375 vi->rvq->vq_ops->kick(vi->rvq);
376 }
377
378 static void skb_recv_done(struct virtqueue *rvq)
379 {
380 struct virtnet_info *vi = rvq->vdev->priv;
381 /* Schedule NAPI, Suppress further interrupts if successful. */
382 if (napi_schedule_prep(&vi->napi)) {
383 rvq->vq_ops->disable_cb(rvq);
384 __napi_schedule(&vi->napi);
385 }
386 }
387
388 static int virtnet_poll(struct napi_struct *napi, int budget)
389 {
390 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
391 struct sk_buff *skb = NULL;
392 unsigned int len, received = 0;
393
394 again:
395 while (received < budget &&
396 (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
397 __skb_unlink(skb, &vi->recv);
398 receive_skb(vi->dev, skb, len);
399 vi->num--;
400 received++;
401 }
402
403 /* FIXME: If we oom and completely run out of inbufs, we need
404 * to start a timer trying to fill more. */
405 if (vi->num < vi->max / 2)
406 try_fill_recv(vi);
407
408 /* Out of packets? */
409 if (received < budget) {
410 napi_complete(napi);
411 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
412 && napi_schedule_prep(napi)) {
413 vi->rvq->vq_ops->disable_cb(vi->rvq);
414 __napi_schedule(napi);
415 goto again;
416 }
417 }
418
419 return received;
420 }
421
422 static void free_old_xmit_skbs(struct virtnet_info *vi)
423 {
424 struct sk_buff *skb;
425 unsigned int len;
426
427 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
428 pr_debug("Sent skb %p\n", skb);
429 __skb_unlink(skb, &vi->send);
430 vi->dev->stats.tx_bytes += skb->len;
431 vi->dev->stats.tx_packets++;
432 kfree_skb(skb);
433 }
434 }
435
436 /* If the virtio transport doesn't always notify us when all in-flight packets
437 * are consumed, we fall back to using this function on a timer to free them. */
438 static void xmit_free(unsigned long data)
439 {
440 struct virtnet_info *vi = (void *)data;
441
442 netif_tx_lock(vi->dev);
443
444 free_old_xmit_skbs(vi);
445
446 if (!skb_queue_empty(&vi->send))
447 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
448
449 netif_tx_unlock(vi->dev);
450 }
451
452 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
453 {
454 int num, err;
455 struct scatterlist sg[2+MAX_SKB_FRAGS];
456 struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
457 struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
458 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
459
460 sg_init_table(sg, 2+MAX_SKB_FRAGS);
461
462 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
463
464 if (skb->ip_summed == CHECKSUM_PARTIAL) {
465 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
466 hdr->csum_start = skb->csum_start - skb_headroom(skb);
467 hdr->csum_offset = skb->csum_offset;
468 } else {
469 hdr->flags = 0;
470 hdr->csum_offset = hdr->csum_start = 0;
471 }
472
473 if (skb_is_gso(skb)) {
474 hdr->hdr_len = skb_headlen(skb);
475 hdr->gso_size = skb_shinfo(skb)->gso_size;
476 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
477 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
478 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
479 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
480 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
481 hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
482 else
483 BUG();
484 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
485 hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
486 } else {
487 hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
488 hdr->gso_size = hdr->hdr_len = 0;
489 }
490
491 mhdr->num_buffers = 0;
492
493 /* Encode metadata header at front. */
494 if (vi->mergeable_rx_bufs)
495 sg_set_buf(sg, mhdr, sizeof(*mhdr));
496 else
497 sg_set_buf(sg, hdr, sizeof(*hdr));
498
499 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
500
501 err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
502 if (!err && !vi->free_in_tasklet)
503 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
504
505 return err;
506 }
507
508 static void xmit_tasklet(unsigned long data)
509 {
510 struct virtnet_info *vi = (void *)data;
511
512 netif_tx_lock_bh(vi->dev);
513 if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) {
514 vi->svq->vq_ops->kick(vi->svq);
515 vi->last_xmit_skb = NULL;
516 }
517 if (vi->free_in_tasklet)
518 free_old_xmit_skbs(vi);
519 netif_tx_unlock_bh(vi->dev);
520 }
521
522 static int start_xmit(struct sk_buff *skb, struct net_device *dev)
523 {
524 struct virtnet_info *vi = netdev_priv(dev);
525
526 again:
527 /* Free up any pending old buffers before queueing new ones. */
528 free_old_xmit_skbs(vi);
529
530 /* If we has a buffer left over from last time, send it now. */
531 if (unlikely(vi->last_xmit_skb) &&
532 xmit_skb(vi, vi->last_xmit_skb) != 0)
533 goto stop_queue;
534
535 vi->last_xmit_skb = NULL;
536
537 /* Put new one in send queue and do transmit */
538 if (likely(skb)) {
539 __skb_queue_head(&vi->send, skb);
540 if (xmit_skb(vi, skb) != 0) {
541 vi->last_xmit_skb = skb;
542 skb = NULL;
543 goto stop_queue;
544 }
545 }
546 done:
547 vi->svq->vq_ops->kick(vi->svq);
548 return NETDEV_TX_OK;
549
550 stop_queue:
551 pr_debug("%s: virtio not prepared to send\n", dev->name);
552 netif_stop_queue(dev);
553
554 /* Activate callback for using skbs: if this returns false it
555 * means some were used in the meantime. */
556 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
557 vi->svq->vq_ops->disable_cb(vi->svq);
558 netif_start_queue(dev);
559 goto again;
560 }
561 if (skb) {
562 /* Drop this skb: we only queue one. */
563 vi->dev->stats.tx_dropped++;
564 kfree_skb(skb);
565 }
566 goto done;
567 }
568
569 static int virtnet_set_mac_address(struct net_device *dev, void *p)
570 {
571 struct virtnet_info *vi = netdev_priv(dev);
572 struct virtio_device *vdev = vi->vdev;
573 int ret;
574
575 ret = eth_mac_addr(dev, p);
576 if (ret)
577 return ret;
578
579 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
580 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
581 dev->dev_addr, dev->addr_len);
582
583 return 0;
584 }
585
586 #ifdef CONFIG_NET_POLL_CONTROLLER
587 static void virtnet_netpoll(struct net_device *dev)
588 {
589 struct virtnet_info *vi = netdev_priv(dev);
590
591 napi_schedule(&vi->napi);
592 }
593 #endif
594
595 static int virtnet_open(struct net_device *dev)
596 {
597 struct virtnet_info *vi = netdev_priv(dev);
598
599 napi_enable(&vi->napi);
600
601 /* If all buffers were filled by other side before we napi_enabled, we
602 * won't get another interrupt, so process any outstanding packets
603 * now. virtnet_poll wants re-enable the queue, so we disable here.
604 * We synchronize against interrupts via NAPI_STATE_SCHED */
605 if (napi_schedule_prep(&vi->napi)) {
606 vi->rvq->vq_ops->disable_cb(vi->rvq);
607 __napi_schedule(&vi->napi);
608 }
609 return 0;
610 }
611
612 /*
613 * Send command via the control virtqueue and check status. Commands
614 * supported by the hypervisor, as indicated by feature bits, should
615 * never fail unless improperly formated.
616 */
617 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
618 struct scatterlist *data, int out, int in)
619 {
620 struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
621 struct virtio_net_ctrl_hdr ctrl;
622 virtio_net_ctrl_ack status = ~0;
623 unsigned int tmp;
624 int i;
625
626 /* Caller should know better */
627 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
628 (out + in > VIRTNET_SEND_COMMAND_SG_MAX));
629
630 out++; /* Add header */
631 in++; /* Add return status */
632
633 ctrl.class = class;
634 ctrl.cmd = cmd;
635
636 sg_init_table(sg, out + in);
637
638 sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
639 for_each_sg(data, s, out + in - 2, i)
640 sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
641 sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
642
643 BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi));
644
645 vi->cvq->vq_ops->kick(vi->cvq);
646
647 /*
648 * Spin for a response, the kick causes an ioport write, trapping
649 * into the hypervisor, so the request should be handled immediately.
650 */
651 while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp))
652 cpu_relax();
653
654 return status == VIRTIO_NET_OK;
655 }
656
657 static int virtnet_close(struct net_device *dev)
658 {
659 struct virtnet_info *vi = netdev_priv(dev);
660
661 napi_disable(&vi->napi);
662
663 return 0;
664 }
665
666 static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
667 {
668 struct virtnet_info *vi = netdev_priv(dev);
669 struct virtio_device *vdev = vi->vdev;
670
671 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
672 return -ENOSYS;
673
674 return ethtool_op_set_tx_hw_csum(dev, data);
675 }
676
677 static void virtnet_set_rx_mode(struct net_device *dev)
678 {
679 struct virtnet_info *vi = netdev_priv(dev);
680 struct scatterlist sg[2];
681 u8 promisc, allmulti;
682 struct virtio_net_ctrl_mac *mac_data;
683 struct dev_addr_list *addr;
684 struct netdev_hw_addr *ha;
685 void *buf;
686 int i;
687
688 /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
689 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
690 return;
691
692 promisc = ((dev->flags & IFF_PROMISC) != 0);
693 allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
694
695 sg_init_one(sg, &promisc, sizeof(promisc));
696
697 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
698 VIRTIO_NET_CTRL_RX_PROMISC,
699 sg, 1, 0))
700 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
701 promisc ? "en" : "dis");
702
703 sg_init_one(sg, &allmulti, sizeof(allmulti));
704
705 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
706 VIRTIO_NET_CTRL_RX_ALLMULTI,
707 sg, 1, 0))
708 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
709 allmulti ? "en" : "dis");
710
711 /* MAC filter - use one buffer for both lists */
712 mac_data = buf = kzalloc(((dev->uc.count + dev->mc_count) * ETH_ALEN) +
713 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
714 if (!buf) {
715 dev_warn(&dev->dev, "No memory for MAC address buffer\n");
716 return;
717 }
718
719 sg_init_table(sg, 2);
720
721 /* Store the unicast list and count in the front of the buffer */
722 mac_data->entries = dev->uc.count;
723 i = 0;
724 list_for_each_entry(ha, &dev->uc.list, list)
725 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
726
727 sg_set_buf(&sg[0], mac_data,
728 sizeof(mac_data->entries) + (dev->uc.count * ETH_ALEN));
729
730 /* multicast list and count fill the end */
731 mac_data = (void *)&mac_data->macs[dev->uc.count][0];
732
733 mac_data->entries = dev->mc_count;
734 addr = dev->mc_list;
735 for (i = 0; i < dev->mc_count; i++, addr = addr->next)
736 memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN);
737
738 sg_set_buf(&sg[1], mac_data,
739 sizeof(mac_data->entries) + (dev->mc_count * ETH_ALEN));
740
741 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
742 VIRTIO_NET_CTRL_MAC_TABLE_SET,
743 sg, 2, 0))
744 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
745
746 kfree(buf);
747 }
748
749 static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
750 {
751 struct virtnet_info *vi = netdev_priv(dev);
752 struct scatterlist sg;
753
754 sg_init_one(&sg, &vid, sizeof(vid));
755
756 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
757 VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
758 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
759 }
760
761 static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
762 {
763 struct virtnet_info *vi = netdev_priv(dev);
764 struct scatterlist sg;
765
766 sg_init_one(&sg, &vid, sizeof(vid));
767
768 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
769 VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
770 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
771 }
772
773 static struct ethtool_ops virtnet_ethtool_ops = {
774 .set_tx_csum = virtnet_set_tx_csum,
775 .set_sg = ethtool_op_set_sg,
776 .set_tso = ethtool_op_set_tso,
777 .get_link = ethtool_op_get_link,
778 };
779
780 #define MIN_MTU 68
781 #define MAX_MTU 65535
782
783 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
784 {
785 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
786 return -EINVAL;
787 dev->mtu = new_mtu;
788 return 0;
789 }
790
791 static const struct net_device_ops virtnet_netdev = {
792 .ndo_open = virtnet_open,
793 .ndo_stop = virtnet_close,
794 .ndo_start_xmit = start_xmit,
795 .ndo_validate_addr = eth_validate_addr,
796 .ndo_set_mac_address = virtnet_set_mac_address,
797 .ndo_set_rx_mode = virtnet_set_rx_mode,
798 .ndo_change_mtu = virtnet_change_mtu,
799 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
800 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
801 #ifdef CONFIG_NET_POLL_CONTROLLER
802 .ndo_poll_controller = virtnet_netpoll,
803 #endif
804 };
805
806 static void virtnet_update_status(struct virtnet_info *vi)
807 {
808 u16 v;
809
810 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS))
811 return;
812
813 vi->vdev->config->get(vi->vdev,
814 offsetof(struct virtio_net_config, status),
815 &v, sizeof(v));
816
817 /* Ignore unknown (future) status bits */
818 v &= VIRTIO_NET_S_LINK_UP;
819
820 if (vi->status == v)
821 return;
822
823 vi->status = v;
824
825 if (vi->status & VIRTIO_NET_S_LINK_UP) {
826 netif_carrier_on(vi->dev);
827 netif_wake_queue(vi->dev);
828 } else {
829 netif_carrier_off(vi->dev);
830 netif_stop_queue(vi->dev);
831 }
832 }
833
834 static void virtnet_config_changed(struct virtio_device *vdev)
835 {
836 struct virtnet_info *vi = vdev->priv;
837
838 virtnet_update_status(vi);
839 }
840
841 static int virtnet_probe(struct virtio_device *vdev)
842 {
843 int err;
844 struct net_device *dev;
845 struct virtnet_info *vi;
846 struct virtqueue *vqs[3];
847 vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
848 const char *names[] = { "input", "output", "control" };
849 int nvqs;
850
851 /* Allocate ourselves a network device with room for our info */
852 dev = alloc_etherdev(sizeof(struct virtnet_info));
853 if (!dev)
854 return -ENOMEM;
855
856 /* Set up network device as normal. */
857 dev->netdev_ops = &virtnet_netdev;
858 dev->features = NETIF_F_HIGHDMA;
859 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
860 SET_NETDEV_DEV(dev, &vdev->dev);
861
862 /* Do we support "hardware" checksums? */
863 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
864 /* This opens up the world of extra features. */
865 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
866 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
867 dev->features |= NETIF_F_TSO | NETIF_F_UFO
868 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
869 }
870 /* Individual feature bits: what can host handle? */
871 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
872 dev->features |= NETIF_F_TSO;
873 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
874 dev->features |= NETIF_F_TSO6;
875 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
876 dev->features |= NETIF_F_TSO_ECN;
877 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
878 dev->features |= NETIF_F_UFO;
879 }
880
881 /* Configuration may specify what MAC to use. Otherwise random. */
882 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
883 vdev->config->get(vdev,
884 offsetof(struct virtio_net_config, mac),
885 dev->dev_addr, dev->addr_len);
886 } else
887 random_ether_addr(dev->dev_addr);
888
889 /* Set up our device-specific information */
890 vi = netdev_priv(dev);
891 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
892 vi->dev = dev;
893 vi->vdev = vdev;
894 vdev->priv = vi;
895 vi->pages = NULL;
896
897 /* If they give us a callback when all buffers are done, we don't need
898 * the timer. */
899 vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY);
900
901 /* If we can receive ANY GSO packets, we must allocate large ones. */
902 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4)
903 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)
904 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
905 vi->big_packets = true;
906
907 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
908 vi->mergeable_rx_bufs = true;
909
910 /* We expect two virtqueues, receive then send,
911 * and optionally control. */
912 nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
913
914 err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);
915 if (err)
916 goto free;
917
918 vi->rvq = vqs[0];
919 vi->svq = vqs[1];
920
921 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
922 vi->cvq = vqs[2];
923
924 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
925 dev->features |= NETIF_F_HW_VLAN_FILTER;
926 }
927
928 /* Initialize our empty receive and send queues. */
929 skb_queue_head_init(&vi->recv);
930 skb_queue_head_init(&vi->send);
931
932 tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi);
933
934 if (!vi->free_in_tasklet)
935 setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
936
937 err = register_netdev(dev);
938 if (err) {
939 pr_debug("virtio_net: registering device failed\n");
940 goto free_vqs;
941 }
942
943 /* Last of all, set up some receive buffers. */
944 try_fill_recv(vi);
945
946 /* If we didn't even get one input buffer, we're useless. */
947 if (vi->num == 0) {
948 err = -ENOMEM;
949 goto unregister;
950 }
951
952 vi->status = VIRTIO_NET_S_LINK_UP;
953 virtnet_update_status(vi);
954 netif_carrier_on(dev);
955
956 pr_debug("virtnet: registered device %s\n", dev->name);
957 return 0;
958
959 unregister:
960 unregister_netdev(dev);
961 free_vqs:
962 vdev->config->del_vqs(vdev);
963 free:
964 free_netdev(dev);
965 return err;
966 }
967
968 static void virtnet_remove(struct virtio_device *vdev)
969 {
970 struct virtnet_info *vi = vdev->priv;
971 struct sk_buff *skb;
972
973 /* Stop all the virtqueues. */
974 vdev->config->reset(vdev);
975
976 if (!vi->free_in_tasklet)
977 del_timer_sync(&vi->xmit_free_timer);
978
979 /* Free our skbs in send and recv queues, if any. */
980 while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
981 kfree_skb(skb);
982 vi->num--;
983 }
984 __skb_queue_purge(&vi->send);
985
986 BUG_ON(vi->num != 0);
987
988 unregister_netdev(vi->dev);
989
990 vdev->config->del_vqs(vi->vdev);
991
992 while (vi->pages)
993 __free_pages(get_a_page(vi, GFP_KERNEL), 0);
994
995 free_netdev(vi->dev);
996 }
997
998 static struct virtio_device_id id_table[] = {
999 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
1000 { 0 },
1001 };
1002
1003 static unsigned int features[] = {
1004 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
1005 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
1006 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
1007 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
1008 VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */
1009 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
1010 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
1011 VIRTIO_F_NOTIFY_ON_EMPTY,
1012 };
1013
1014 static struct virtio_driver virtio_net = {
1015 .feature_table = features,
1016 .feature_table_size = ARRAY_SIZE(features),
1017 .driver.name = KBUILD_MODNAME,
1018 .driver.owner = THIS_MODULE,
1019 .id_table = id_table,
1020 .probe = virtnet_probe,
1021 .remove = __devexit_p(virtnet_remove),
1022 .config_changed = virtnet_config_changed,
1023 };
1024
1025 static int __init init(void)
1026 {
1027 return register_virtio_driver(&virtio_net);
1028 }
1029
1030 static void __exit fini(void)
1031 {
1032 unregister_virtio_driver(&virtio_net);
1033 }
1034 module_init(init);
1035 module_exit(fini);
1036
1037 MODULE_DEVICE_TABLE(virtio, id_table);
1038 MODULE_DESCRIPTION("Virtio network driver");
1039 MODULE_LICENSE("GPL");
Support for the Chinese Samsung S3C2440 based development boards