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Linux 2.6.33
[pohmelfs.git] / drivers / net / virtio_net.c
blob9ead30bd00c4227522aabc600e8032c02765d82f
1 /* A 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 /* Number of input buffers, and max we've ever had. */
51 unsigned int num, max;
52
53 /* I like... big packets and I cannot lie! */
54 bool big_packets;
55
56 /* Host will merge rx buffers for big packets (shake it! shake it!) */
57 bool mergeable_rx_bufs;
58
59 /* Receive & send queues. */
60 struct sk_buff_head recv;
61 struct sk_buff_head send;
62
63 /* Work struct for refilling if we run low on memory. */
64 struct delayed_work refill;
65
66 /* Chain pages by the private ptr. */
67 struct page *pages;
68 };
69
70 struct skb_vnet_hdr {
71 union {
72 struct virtio_net_hdr hdr;
73 struct virtio_net_hdr_mrg_rxbuf mhdr;
74 };
75 unsigned int num_sg;
76 };
77
78 static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
79 {
80 return (struct skb_vnet_hdr *)skb->cb;
81 }
82
83 static void give_a_page(struct virtnet_info *vi, struct page *page)
84 {
85 page->private = (unsigned long)vi->pages;
86 vi->pages = page;
87 }
88
89 static void trim_pages(struct virtnet_info *vi, struct sk_buff *skb)
90 {
91 unsigned int i;
92
93 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
94 give_a_page(vi, skb_shinfo(skb)->frags[i].page);
95 skb_shinfo(skb)->nr_frags = 0;
96 skb->data_len = 0;
97 }
98
99 static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
100 {
101 struct page *p = vi->pages;
102
103 if (p)
104 vi->pages = (struct page *)p->private;
105 else
106 p = alloc_page(gfp_mask);
107 return p;
108 }
109
110 static void skb_xmit_done(struct virtqueue *svq)
111 {
112 struct virtnet_info *vi = svq->vdev->priv;
113
114 /* Suppress further interrupts. */
115 svq->vq_ops->disable_cb(svq);
116
117 /* We were probably waiting for more output buffers. */
118 netif_wake_queue(vi->dev);
119 }
120
121 static void receive_skb(struct net_device *dev, struct sk_buff *skb,
122 unsigned len)
123 {
124 struct virtnet_info *vi = netdev_priv(dev);
125 struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
126 int err;
127 int i;
128
129 if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
130 pr_debug("%s: short packet %i\n", dev->name, len);
131 dev->stats.rx_length_errors++;
132 goto drop;
133 }
134
135 if (vi->mergeable_rx_bufs) {
136 unsigned int copy;
137 char *p = page_address(skb_shinfo(skb)->frags[0].page);
138
139 if (len > PAGE_SIZE)
140 len = PAGE_SIZE;
141 len -= sizeof(struct virtio_net_hdr_mrg_rxbuf);
142
143 memcpy(&hdr->mhdr, p, sizeof(hdr->mhdr));
144 p += sizeof(hdr->mhdr);
145
146 copy = len;
147 if (copy > skb_tailroom(skb))
148 copy = skb_tailroom(skb);
149
150 memcpy(skb_put(skb, copy), p, copy);
151
152 len -= copy;
153
154 if (!len) {
155 give_a_page(vi, skb_shinfo(skb)->frags[0].page);
156 skb_shinfo(skb)->nr_frags--;
157 } else {
158 skb_shinfo(skb)->frags[0].page_offset +=
159 sizeof(hdr->mhdr) + copy;
160 skb_shinfo(skb)->frags[0].size = len;
161 skb->data_len += len;
162 skb->len += len;
163 }
164
165 while (--hdr->mhdr.num_buffers) {
166 struct sk_buff *nskb;
167
168 i = skb_shinfo(skb)->nr_frags;
169 if (i >= MAX_SKB_FRAGS) {
170 pr_debug("%s: packet too long %d\n", dev->name,
171 len);
172 dev->stats.rx_length_errors++;
173 goto drop;
174 }
175
176 nskb = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
177 if (!nskb) {
178 pr_debug("%s: rx error: %d buffers missing\n",
179 dev->name, hdr->mhdr.num_buffers);
180 dev->stats.rx_length_errors++;
181 goto drop;
182 }
183
184 __skb_unlink(nskb, &vi->recv);
185 vi->num--;
186
187 skb_shinfo(skb)->frags[i] = skb_shinfo(nskb)->frags[0];
188 skb_shinfo(nskb)->nr_frags = 0;
189 kfree_skb(nskb);
190
191 if (len > PAGE_SIZE)
192 len = PAGE_SIZE;
193
194 skb_shinfo(skb)->frags[i].size = len;
195 skb_shinfo(skb)->nr_frags++;
196 skb->data_len += len;
197 skb->len += len;
198 }
199 } else {
200 len -= sizeof(hdr->hdr);
201
202 if (len <= MAX_PACKET_LEN)
203 trim_pages(vi, skb);
204
205 err = pskb_trim(skb, len);
206 if (err) {
207 pr_debug("%s: pskb_trim failed %i %d\n", dev->name,
208 len, err);
209 dev->stats.rx_dropped++;
210 goto drop;
211 }
212 }
213
214 skb->truesize += skb->data_len;
215 dev->stats.rx_bytes += skb->len;
216 dev->stats.rx_packets++;
217
218 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
219 pr_debug("Needs csum!\n");
220 if (!skb_partial_csum_set(skb,
221 hdr->hdr.csum_start,
222 hdr->hdr.csum_offset))
223 goto frame_err;
224 }
225
226 skb->protocol = eth_type_trans(skb, dev);
227 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
228 ntohs(skb->protocol), skb->len, skb->pkt_type);
229
230 if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
231 pr_debug("GSO!\n");
232 switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
233 case VIRTIO_NET_HDR_GSO_TCPV4:
234 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
235 break;
236 case VIRTIO_NET_HDR_GSO_UDP:
237 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
238 break;
239 case VIRTIO_NET_HDR_GSO_TCPV6:
240 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
241 break;
242 default:
243 if (net_ratelimit())
244 printk(KERN_WARNING "%s: bad gso type %u.\n",
245 dev->name, hdr->hdr.gso_type);
246 goto frame_err;
247 }
248
249 if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
250 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
251
252 skb_shinfo(skb)->gso_size = hdr->hdr.gso_size;
253 if (skb_shinfo(skb)->gso_size == 0) {
254 if (net_ratelimit())
255 printk(KERN_WARNING "%s: zero gso size.\n",
256 dev->name);
257 goto frame_err;
258 }
259
260 /* Header must be checked, and gso_segs computed. */
261 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
262 skb_shinfo(skb)->gso_segs = 0;
263 }
264
265 netif_receive_skb(skb);
266 return;
267
268 frame_err:
269 dev->stats.rx_frame_errors++;
270 drop:
271 dev_kfree_skb(skb);
272 }
273
274 static bool try_fill_recv_maxbufs(struct virtnet_info *vi, gfp_t gfp)
275 {
276 struct sk_buff *skb;
277 struct scatterlist sg[2+MAX_SKB_FRAGS];
278 int num, err, i;
279 bool oom = false;
280
281 sg_init_table(sg, 2+MAX_SKB_FRAGS);
282 do {
283 struct skb_vnet_hdr *hdr;
284
285 skb = netdev_alloc_skb_ip_align(vi->dev, MAX_PACKET_LEN);
286 if (unlikely(!skb)) {
287 oom = true;
288 break;
289 }
290
291 skb_put(skb, MAX_PACKET_LEN);
292
293 hdr = skb_vnet_hdr(skb);
294 sg_set_buf(sg, &hdr->hdr, sizeof(hdr->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);
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 < 0) {
318 skb_unlink(skb, &vi->recv);
319 trim_pages(vi, skb);
320 kfree_skb(skb);
321 break;
322 }
323 vi->num++;
324 } while (err >= num);
325 if (unlikely(vi->num > vi->max))
326 vi->max = vi->num;
327 vi->rvq->vq_ops->kick(vi->rvq);
328 return !oom;
329 }
330
331 /* Returns false if we couldn't fill entirely (OOM). */
332 static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
333 {
334 struct sk_buff *skb;
335 struct scatterlist sg[1];
336 int err;
337 bool oom = false;
338
339 if (!vi->mergeable_rx_bufs)
340 return try_fill_recv_maxbufs(vi, gfp);
341
342 do {
343 skb_frag_t *f;
344
345 skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
346 if (unlikely(!skb)) {
347 oom = true;
348 break;
349 }
350
351 f = &skb_shinfo(skb)->frags[0];
352 f->page = get_a_page(vi, gfp);
353 if (!f->page) {
354 oom = true;
355 kfree_skb(skb);
356 break;
357 }
358
359 f->page_offset = 0;
360 f->size = PAGE_SIZE;
361
362 skb_shinfo(skb)->nr_frags++;
363
364 sg_init_one(sg, page_address(f->page), PAGE_SIZE);
365 skb_queue_head(&vi->recv, skb);
366
367 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb);
368 if (err < 0) {
369 skb_unlink(skb, &vi->recv);
370 kfree_skb(skb);
371 break;
372 }
373 vi->num++;
374 } while (err > 0);
375 if (unlikely(vi->num > vi->max))
376 vi->max = vi->num;
377 vi->rvq->vq_ops->kick(vi->rvq);
378 return !oom;
379 }
380
381 static void skb_recv_done(struct virtqueue *rvq)
382 {
383 struct virtnet_info *vi = rvq->vdev->priv;
384 /* Schedule NAPI, Suppress further interrupts if successful. */
385 if (napi_schedule_prep(&vi->napi)) {
386 rvq->vq_ops->disable_cb(rvq);
387 __napi_schedule(&vi->napi);
388 }
389 }
390
391 static void refill_work(struct work_struct *work)
392 {
393 struct virtnet_info *vi;
394 bool still_empty;
395
396 vi = container_of(work, struct virtnet_info, refill.work);
397 napi_disable(&vi->napi);
398 still_empty = !try_fill_recv(vi, GFP_KERNEL);
399 napi_enable(&vi->napi);
400
401 /* In theory, this can happen: if we don't get any buffers in
402 * we will *never* try to fill again. */
403 if (still_empty)
404 schedule_delayed_work(&vi->refill, HZ/2);
405 }
406
407 static int virtnet_poll(struct napi_struct *napi, int budget)
408 {
409 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
410 struct sk_buff *skb = NULL;
411 unsigned int len, received = 0;
412
413 again:
414 while (received < budget &&
415 (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
416 __skb_unlink(skb, &vi->recv);
417 receive_skb(vi->dev, skb, len);
418 vi->num--;
419 received++;
420 }
421
422 if (vi->num < vi->max / 2) {
423 if (!try_fill_recv(vi, GFP_ATOMIC))
424 schedule_delayed_work(&vi->refill, 0);
425 }
426
427 /* Out of packets? */
428 if (received < budget) {
429 napi_complete(napi);
430 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) &&
431 napi_schedule_prep(napi)) {
432 vi->rvq->vq_ops->disable_cb(vi->rvq);
433 __napi_schedule(napi);
434 goto again;
435 }
436 }
437
438 return received;
439 }
440
441 static unsigned int free_old_xmit_skbs(struct virtnet_info *vi)
442 {
443 struct sk_buff *skb;
444 unsigned int len, tot_sgs = 0;
445
446 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
447 pr_debug("Sent skb %p\n", skb);
448 __skb_unlink(skb, &vi->send);
449 vi->dev->stats.tx_bytes += skb->len;
450 vi->dev->stats.tx_packets++;
451 tot_sgs += skb_vnet_hdr(skb)->num_sg;
452 dev_kfree_skb_any(skb);
453 }
454 return tot_sgs;
455 }
456
457 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
458 {
459 struct scatterlist sg[2+MAX_SKB_FRAGS];
460 struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
461 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
462
463 sg_init_table(sg, 2+MAX_SKB_FRAGS);
464
465 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
466
467 if (skb->ip_summed == CHECKSUM_PARTIAL) {
468 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
469 hdr->hdr.csum_start = skb->csum_start - skb_headroom(skb);
470 hdr->hdr.csum_offset = skb->csum_offset;
471 } else {
472 hdr->hdr.flags = 0;
473 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
474 }
475
476 if (skb_is_gso(skb)) {
477 hdr->hdr.hdr_len = skb_headlen(skb);
478 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
479 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
480 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
481 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
482 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
483 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
484 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
485 else
486 BUG();
487 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
488 hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
489 } else {
490 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
491 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
492 }
493
494 hdr->mhdr.num_buffers = 0;
495
496 /* Encode metadata header at front. */
497 if (vi->mergeable_rx_bufs)
498 sg_set_buf(sg, &hdr->mhdr, sizeof(hdr->mhdr));
499 else
500 sg_set_buf(sg, &hdr->hdr, sizeof(hdr->hdr));
501
502 hdr->num_sg = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
503 return vi->svq->vq_ops->add_buf(vi->svq, sg, hdr->num_sg, 0, skb);
504 }
505
506 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
507 {
508 struct virtnet_info *vi = netdev_priv(dev);
509 int capacity;
510
511 again:
512 /* Free up any pending old buffers before queueing new ones. */
513 free_old_xmit_skbs(vi);
514
515 /* Try to transmit */
516 capacity = xmit_skb(vi, skb);
517
518 /* This can happen with OOM and indirect buffers. */
519 if (unlikely(capacity < 0)) {
520 netif_stop_queue(dev);
521 dev_warn(&dev->dev, "Unexpected full queue\n");
522 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
523 vi->svq->vq_ops->disable_cb(vi->svq);
524 netif_start_queue(dev);
525 goto again;
526 }
527 return NETDEV_TX_BUSY;
528 }
529 vi->svq->vq_ops->kick(vi->svq);
530
531 /*
532 * Put new one in send queue. You'd expect we'd need this before
533 * xmit_skb calls add_buf(), since the callback can be triggered
534 * immediately after that. But since the callback just triggers
535 * another call back here, normal network xmit locking prevents the
536 * race.
537 */
538 __skb_queue_head(&vi->send, skb);
539
540 /* Don't wait up for transmitted skbs to be freed. */
541 skb_orphan(skb);
542 nf_reset(skb);
543
544 /* Apparently nice girls don't return TX_BUSY; stop the queue
545 * before it gets out of hand. Naturally, this wastes entries. */
546 if (capacity < 2+MAX_SKB_FRAGS) {
547 netif_stop_queue(dev);
548 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
549 /* More just got used, free them then recheck. */
550 capacity += free_old_xmit_skbs(vi);
551 if (capacity >= 2+MAX_SKB_FRAGS) {
552 netif_start_queue(dev);
553 vi->svq->vq_ops->disable_cb(vi->svq);
554 }
555 }
556 }
557
558 return NETDEV_TX_OK;
559 }
560
561 static int virtnet_set_mac_address(struct net_device *dev, void *p)
562 {
563 struct virtnet_info *vi = netdev_priv(dev);
564 struct virtio_device *vdev = vi->vdev;
565 int ret;
566
567 ret = eth_mac_addr(dev, p);
568 if (ret)
569 return ret;
570
571 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
572 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
573 dev->dev_addr, dev->addr_len);
574
575 return 0;
576 }
577
578 #ifdef CONFIG_NET_POLL_CONTROLLER
579 static void virtnet_netpoll(struct net_device *dev)
580 {
581 struct virtnet_info *vi = netdev_priv(dev);
582
583 napi_schedule(&vi->napi);
584 }
585 #endif
586
587 static int virtnet_open(struct net_device *dev)
588 {
589 struct virtnet_info *vi = netdev_priv(dev);
590
591 napi_enable(&vi->napi);
592
593 /* If all buffers were filled by other side before we napi_enabled, we
594 * won't get another interrupt, so process any outstanding packets
595 * now. virtnet_poll wants re-enable the queue, so we disable here.
596 * We synchronize against interrupts via NAPI_STATE_SCHED */
597 if (napi_schedule_prep(&vi->napi)) {
598 vi->rvq->vq_ops->disable_cb(vi->rvq);
599 __napi_schedule(&vi->napi);
600 }
601 return 0;
602 }
603
604 /*
605 * Send command via the control virtqueue and check status. Commands
606 * supported by the hypervisor, as indicated by feature bits, should
607 * never fail unless improperly formated.
608 */
609 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
610 struct scatterlist *data, int out, int in)
611 {
612 struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
613 struct virtio_net_ctrl_hdr ctrl;
614 virtio_net_ctrl_ack status = ~0;
615 unsigned int tmp;
616 int i;
617
618 /* Caller should know better */
619 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
620 (out + in > VIRTNET_SEND_COMMAND_SG_MAX));
621
622 out++; /* Add header */
623 in++; /* Add return status */
624
625 ctrl.class = class;
626 ctrl.cmd = cmd;
627
628 sg_init_table(sg, out + in);
629
630 sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
631 for_each_sg(data, s, out + in - 2, i)
632 sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
633 sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
634
635 BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) < 0);
636
637 vi->cvq->vq_ops->kick(vi->cvq);
638
639 /*
640 * Spin for a response, the kick causes an ioport write, trapping
641 * into the hypervisor, so the request should be handled immediately.
642 */
643 while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp))
644 cpu_relax();
645
646 return status == VIRTIO_NET_OK;
647 }
648
649 static int virtnet_close(struct net_device *dev)
650 {
651 struct virtnet_info *vi = netdev_priv(dev);
652
653 napi_disable(&vi->napi);
654
655 return 0;
656 }
657
658 static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
659 {
660 struct virtnet_info *vi = netdev_priv(dev);
661 struct virtio_device *vdev = vi->vdev;
662
663 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
664 return -ENOSYS;
665
666 return ethtool_op_set_tx_hw_csum(dev, data);
667 }
668
669 static void virtnet_set_rx_mode(struct net_device *dev)
670 {
671 struct virtnet_info *vi = netdev_priv(dev);
672 struct scatterlist sg[2];
673 u8 promisc, allmulti;
674 struct virtio_net_ctrl_mac *mac_data;
675 struct dev_addr_list *addr;
676 struct netdev_hw_addr *ha;
677 void *buf;
678 int i;
679
680 /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
681 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
682 return;
683
684 promisc = ((dev->flags & IFF_PROMISC) != 0);
685 allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
686
687 sg_init_one(sg, &promisc, sizeof(promisc));
688
689 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
690 VIRTIO_NET_CTRL_RX_PROMISC,
691 sg, 1, 0))
692 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
693 promisc ? "en" : "dis");
694
695 sg_init_one(sg, &allmulti, sizeof(allmulti));
696
697 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
698 VIRTIO_NET_CTRL_RX_ALLMULTI,
699 sg, 1, 0))
700 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
701 allmulti ? "en" : "dis");
702
703 /* MAC filter - use one buffer for both lists */
704 mac_data = buf = kzalloc(((dev->uc.count + dev->mc_count) * ETH_ALEN) +
705 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
706 if (!buf) {
707 dev_warn(&dev->dev, "No memory for MAC address buffer\n");
708 return;
709 }
710
711 sg_init_table(sg, 2);
712
713 /* Store the unicast list and count in the front of the buffer */
714 mac_data->entries = dev->uc.count;
715 i = 0;
716 list_for_each_entry(ha, &dev->uc.list, list)
717 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
718
719 sg_set_buf(&sg[0], mac_data,
720 sizeof(mac_data->entries) + (dev->uc.count * ETH_ALEN));
721
722 /* multicast list and count fill the end */
723 mac_data = (void *)&mac_data->macs[dev->uc.count][0];
724
725 mac_data->entries = dev->mc_count;
726 addr = dev->mc_list;
727 for (i = 0; i < dev->mc_count; i++, addr = addr->next)
728 memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN);
729
730 sg_set_buf(&sg[1], mac_data,
731 sizeof(mac_data->entries) + (dev->mc_count * ETH_ALEN));
732
733 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
734 VIRTIO_NET_CTRL_MAC_TABLE_SET,
735 sg, 2, 0))
736 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
737
738 kfree(buf);
739 }
740
741 static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
742 {
743 struct virtnet_info *vi = netdev_priv(dev);
744 struct scatterlist sg;
745
746 sg_init_one(&sg, &vid, sizeof(vid));
747
748 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
749 VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
750 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
751 }
752
753 static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
754 {
755 struct virtnet_info *vi = netdev_priv(dev);
756 struct scatterlist sg;
757
758 sg_init_one(&sg, &vid, sizeof(vid));
759
760 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
761 VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
762 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
763 }
764
765 static const struct ethtool_ops virtnet_ethtool_ops = {
766 .set_tx_csum = virtnet_set_tx_csum,
767 .set_sg = ethtool_op_set_sg,
768 .set_tso = ethtool_op_set_tso,
769 .set_ufo = ethtool_op_set_ufo,
770 .get_link = ethtool_op_get_link,
771 };
772
773 #define MIN_MTU 68
774 #define MAX_MTU 65535
775
776 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
777 {
778 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
779 return -EINVAL;
780 dev->mtu = new_mtu;
781 return 0;
782 }
783
784 static const struct net_device_ops virtnet_netdev = {
785 .ndo_open = virtnet_open,
786 .ndo_stop = virtnet_close,
787 .ndo_start_xmit = start_xmit,
788 .ndo_validate_addr = eth_validate_addr,
789 .ndo_set_mac_address = virtnet_set_mac_address,
790 .ndo_set_rx_mode = virtnet_set_rx_mode,
791 .ndo_change_mtu = virtnet_change_mtu,
792 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
793 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
794 #ifdef CONFIG_NET_POLL_CONTROLLER
795 .ndo_poll_controller = virtnet_netpoll,
796 #endif
797 };
798
799 static void virtnet_update_status(struct virtnet_info *vi)
800 {
801 u16 v;
802
803 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS))
804 return;
805
806 vi->vdev->config->get(vi->vdev,
807 offsetof(struct virtio_net_config, status),
808 &v, sizeof(v));
809
810 /* Ignore unknown (future) status bits */
811 v &= VIRTIO_NET_S_LINK_UP;
812
813 if (vi->status == v)
814 return;
815
816 vi->status = v;
817
818 if (vi->status & VIRTIO_NET_S_LINK_UP) {
819 netif_carrier_on(vi->dev);
820 netif_wake_queue(vi->dev);
821 } else {
822 netif_carrier_off(vi->dev);
823 netif_stop_queue(vi->dev);
824 }
825 }
826
827 static void virtnet_config_changed(struct virtio_device *vdev)
828 {
829 struct virtnet_info *vi = vdev->priv;
830
831 virtnet_update_status(vi);
832 }
833
834 static int virtnet_probe(struct virtio_device *vdev)
835 {
836 int err;
837 struct net_device *dev;
838 struct virtnet_info *vi;
839 struct virtqueue *vqs[3];
840 vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
841 const char *names[] = { "input", "output", "control" };
842 int nvqs;
843
844 /* Allocate ourselves a network device with room for our info */
845 dev = alloc_etherdev(sizeof(struct virtnet_info));
846 if (!dev)
847 return -ENOMEM;
848
849 /* Set up network device as normal. */
850 dev->netdev_ops = &virtnet_netdev;
851 dev->features = NETIF_F_HIGHDMA;
852 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
853 SET_NETDEV_DEV(dev, &vdev->dev);
854
855 /* Do we support "hardware" checksums? */
856 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
857 /* This opens up the world of extra features. */
858 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
859 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
860 dev->features |= NETIF_F_TSO | NETIF_F_UFO
861 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
862 }
863 /* Individual feature bits: what can host handle? */
864 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
865 dev->features |= NETIF_F_TSO;
866 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
867 dev->features |= NETIF_F_TSO6;
868 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
869 dev->features |= NETIF_F_TSO_ECN;
870 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
871 dev->features |= NETIF_F_UFO;
872 }
873
874 /* Configuration may specify what MAC to use. Otherwise random. */
875 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
876 vdev->config->get(vdev,
877 offsetof(struct virtio_net_config, mac),
878 dev->dev_addr, dev->addr_len);
879 } else
880 random_ether_addr(dev->dev_addr);
881
882 /* Set up our device-specific information */
883 vi = netdev_priv(dev);
884 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
885 vi->dev = dev;
886 vi->vdev = vdev;
887 vdev->priv = vi;
888 vi->pages = NULL;
889 INIT_DELAYED_WORK(&vi->refill, refill_work);
890
891 /* If we can receive ANY GSO packets, we must allocate large ones. */
892 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
893 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
894 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
895 vi->big_packets = true;
896
897 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
898 vi->mergeable_rx_bufs = true;
899
900 /* We expect two virtqueues, receive then send,
901 * and optionally control. */
902 nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
903
904 err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);
905 if (err)
906 goto free;
907
908 vi->rvq = vqs[0];
909 vi->svq = vqs[1];
910
911 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
912 vi->cvq = vqs[2];
913
914 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
915 dev->features |= NETIF_F_HW_VLAN_FILTER;
916 }
917
918 /* Initialize our empty receive and send queues. */
919 skb_queue_head_init(&vi->recv);
920 skb_queue_head_init(&vi->send);
921
922 err = register_netdev(dev);
923 if (err) {
924 pr_debug("virtio_net: registering device failed\n");
925 goto free_vqs;
926 }
927
928 /* Last of all, set up some receive buffers. */
929 try_fill_recv(vi, GFP_KERNEL);
930
931 /* If we didn't even get one input buffer, we're useless. */
932 if (vi->num == 0) {
933 err = -ENOMEM;
934 goto unregister;
935 }
936
937 vi->status = VIRTIO_NET_S_LINK_UP;
938 virtnet_update_status(vi);
939 netif_carrier_on(dev);
940
941 pr_debug("virtnet: registered device %s\n", dev->name);
942 return 0;
943
944 unregister:
945 unregister_netdev(dev);
946 cancel_delayed_work_sync(&vi->refill);
947 free_vqs:
948 vdev->config->del_vqs(vdev);
949 free:
950 free_netdev(dev);
951 return err;
952 }
953
954 static void __devexit virtnet_remove(struct virtio_device *vdev)
955 {
956 struct virtnet_info *vi = vdev->priv;
957 struct sk_buff *skb;
958
959 /* Stop all the virtqueues. */
960 vdev->config->reset(vdev);
961
962 /* Free our skbs in send and recv queues, if any. */
963 while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
964 kfree_skb(skb);
965 vi->num--;
966 }
967 __skb_queue_purge(&vi->send);
968
969 BUG_ON(vi->num != 0);
970
971 unregister_netdev(vi->dev);
972 cancel_delayed_work_sync(&vi->refill);
973
974 vdev->config->del_vqs(vi->vdev);
975
976 while (vi->pages)
977 __free_pages(get_a_page(vi, GFP_KERNEL), 0);
978
979 free_netdev(vi->dev);
980 }
981
982 static struct virtio_device_id id_table[] = {
983 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
984 { 0 },
985 };
986
987 static unsigned int features[] = {
988 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
989 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
990 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
991 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
992 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
993 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
994 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
995 };
996
997 static struct virtio_driver virtio_net_driver = {
998 .feature_table = features,
999 .feature_table_size = ARRAY_SIZE(features),
1000 .driver.name = KBUILD_MODNAME,
1001 .driver.owner = THIS_MODULE,
1002 .id_table = id_table,
1003 .probe = virtnet_probe,
1004 .remove = __devexit_p(virtnet_remove),
1005 .config_changed = virtnet_config_changed,
1006 };
1007
1008 static int __init init(void)
1009 {
1010 return register_virtio_driver(&virtio_net_driver);
1011 }
1012
1013 static void __exit fini(void)
1014 {
1015 unregister_virtio_driver(&virtio_net_driver);
1016 }
1017 module_init(init);
1018 module_exit(fini);
1019
1020 MODULE_DEVICE_TABLE(virtio, id_table);
1021 MODULE_DESCRIPTION("Virtio network driver");
1022 MODULE_LICENSE("GPL");