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md: stop defining MAJOR_NR
[linux-2.6.git] / drivers / net / virtio_net.c
blobc68808336c8c4d84e90e03a8d0649592b72c1626
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 struct virtnet_info
41 {
42 struct virtio_device *vdev;
43 struct virtqueue *rvq, *svq;
44 struct net_device *dev;
45 struct napi_struct napi;
46
47 /* The skb we couldn't send because buffers were full. */
48 struct sk_buff *last_xmit_skb;
49
50 /* If we need to free in a timer, this is it. */
51 struct timer_list xmit_free_timer;
52
53 /* Number of input buffers, and max we've ever had. */
54 unsigned int num, max;
55
56 /* For cleaning up after transmission. */
57 struct tasklet_struct tasklet;
58 bool free_in_tasklet;
59
60 /* I like... big packets and I cannot lie! */
61 bool big_packets;
62
63 /* Host will merge rx buffers for big packets (shake it! shake it!) */
64 bool mergeable_rx_bufs;
65
66 /* Receive & send queues. */
67 struct sk_buff_head recv;
68 struct sk_buff_head send;
69
70 /* Chain pages by the private ptr. */
71 struct page *pages;
72 };
73
74 static inline void *skb_vnet_hdr(struct sk_buff *skb)
75 {
76 return (struct virtio_net_hdr *)skb->cb;
77 }
78
79 static void give_a_page(struct virtnet_info *vi, struct page *page)
80 {
81 page->private = (unsigned long)vi->pages;
82 vi->pages = page;
83 }
84
85 static void trim_pages(struct virtnet_info *vi, struct sk_buff *skb)
86 {
87 unsigned int i;
88
89 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
90 give_a_page(vi, skb_shinfo(skb)->frags[i].page);
91 skb_shinfo(skb)->nr_frags = 0;
92 skb->data_len = 0;
93 }
94
95 static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
96 {
97 struct page *p = vi->pages;
98
99 if (p)
100 vi->pages = (struct page *)p->private;
101 else
102 p = alloc_page(gfp_mask);
103 return p;
104 }
105
106 static void skb_xmit_done(struct virtqueue *svq)
107 {
108 struct virtnet_info *vi = svq->vdev->priv;
109
110 /* Suppress further interrupts. */
111 svq->vq_ops->disable_cb(svq);
112
113 /* We were probably waiting for more output buffers. */
114 netif_wake_queue(vi->dev);
115
116 /* Make sure we re-xmit last_xmit_skb: if there are no more packets
117 * queued, start_xmit won't be called. */
118 tasklet_schedule(&vi->tasklet);
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 virtio_net_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 struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
137 unsigned int copy;
138 char *p = page_address(skb_shinfo(skb)->frags[0].page);
139
140 if (len > PAGE_SIZE)
141 len = PAGE_SIZE;
142 len -= sizeof(struct virtio_net_hdr_mrg_rxbuf);
143
144 memcpy(hdr, p, sizeof(*mhdr));
145 p += sizeof(*mhdr);
146
147 copy = len;
148 if (copy > skb_tailroom(skb))
149 copy = skb_tailroom(skb);
150
151 memcpy(skb_put(skb, copy), p, copy);
152
153 len -= copy;
154
155 if (!len) {
156 give_a_page(vi, skb_shinfo(skb)->frags[0].page);
157 skb_shinfo(skb)->nr_frags--;
158 } else {
159 skb_shinfo(skb)->frags[0].page_offset +=
160 sizeof(*mhdr) + copy;
161 skb_shinfo(skb)->frags[0].size = len;
162 skb->data_len += len;
163 skb->len += len;
164 }
165
166 while (--mhdr->num_buffers) {
167 struct sk_buff *nskb;
168
169 i = skb_shinfo(skb)->nr_frags;
170 if (i >= MAX_SKB_FRAGS) {
171 pr_debug("%s: packet too long %d\n", dev->name,
172 len);
173 dev->stats.rx_length_errors++;
174 goto drop;
175 }
176
177 nskb = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
178 if (!nskb) {
179 pr_debug("%s: rx error: %d buffers missing\n",
180 dev->name, mhdr->num_buffers);
181 dev->stats.rx_length_errors++;
182 goto drop;
183 }
184
185 __skb_unlink(nskb, &vi->recv);
186 vi->num--;
187
188 skb_shinfo(skb)->frags[i] = skb_shinfo(nskb)->frags[0];
189 skb_shinfo(nskb)->nr_frags = 0;
190 kfree_skb(nskb);
191
192 if (len > PAGE_SIZE)
193 len = PAGE_SIZE;
194
195 skb_shinfo(skb)->frags[i].size = len;
196 skb_shinfo(skb)->nr_frags++;
197 skb->data_len += len;
198 skb->len += len;
199 }
200 } else {
201 len -= sizeof(struct virtio_net_hdr);
202
203 if (len <= MAX_PACKET_LEN)
204 trim_pages(vi, skb);
205
206 err = pskb_trim(skb, len);
207 if (err) {
208 pr_debug("%s: pskb_trim failed %i %d\n", dev->name,
209 len, err);
210 dev->stats.rx_dropped++;
211 goto drop;
212 }
213 }
214
215 skb->truesize += skb->data_len;
216 dev->stats.rx_bytes += skb->len;
217 dev->stats.rx_packets++;
218
219 if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
220 pr_debug("Needs csum!\n");
221 if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset))
222 goto frame_err;
223 }
224
225 skb->protocol = eth_type_trans(skb, dev);
226 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
227 ntohs(skb->protocol), skb->len, skb->pkt_type);
228
229 if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
230 pr_debug("GSO!\n");
231 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
232 case VIRTIO_NET_HDR_GSO_TCPV4:
233 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
234 break;
235 case VIRTIO_NET_HDR_GSO_UDP:
236 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
237 break;
238 case VIRTIO_NET_HDR_GSO_TCPV6:
239 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
240 break;
241 default:
242 if (net_ratelimit())
243 printk(KERN_WARNING "%s: bad gso type %u.\n",
244 dev->name, hdr->gso_type);
245 goto frame_err;
246 }
247
248 if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
249 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
250
251 skb_shinfo(skb)->gso_size = hdr->gso_size;
252 if (skb_shinfo(skb)->gso_size == 0) {
253 if (net_ratelimit())
254 printk(KERN_WARNING "%s: zero gso size.\n",
255 dev->name);
256 goto frame_err;
257 }
258
259 /* Header must be checked, and gso_segs computed. */
260 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
261 skb_shinfo(skb)->gso_segs = 0;
262 }
263
264 netif_receive_skb(skb);
265 return;
266
267 frame_err:
268 dev->stats.rx_frame_errors++;
269 drop:
270 dev_kfree_skb(skb);
271 }
272
273 static void try_fill_recv_maxbufs(struct virtnet_info *vi)
274 {
275 struct sk_buff *skb;
276 struct scatterlist sg[2+MAX_SKB_FRAGS];
277 int num, err, i;
278
279 sg_init_table(sg, 2+MAX_SKB_FRAGS);
280 for (;;) {
281 struct virtio_net_hdr *hdr;
282
283 skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
284 if (unlikely(!skb))
285 break;
286
287 skb_put(skb, MAX_PACKET_LEN);
288
289 hdr = skb_vnet_hdr(skb);
290 sg_set_buf(sg, hdr, sizeof(*hdr));
291
292 if (vi->big_packets) {
293 for (i = 0; i < MAX_SKB_FRAGS; i++) {
294 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
295 f->page = get_a_page(vi, GFP_ATOMIC);
296 if (!f->page)
297 break;
298
299 f->page_offset = 0;
300 f->size = PAGE_SIZE;
301
302 skb->data_len += PAGE_SIZE;
303 skb->len += PAGE_SIZE;
304
305 skb_shinfo(skb)->nr_frags++;
306 }
307 }
308
309 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
310 skb_queue_head(&vi->recv, skb);
311
312 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
313 if (err) {
314 skb_unlink(skb, &vi->recv);
315 trim_pages(vi, skb);
316 kfree_skb(skb);
317 break;
318 }
319 vi->num++;
320 }
321 if (unlikely(vi->num > vi->max))
322 vi->max = vi->num;
323 vi->rvq->vq_ops->kick(vi->rvq);
324 }
325
326 static void try_fill_recv(struct virtnet_info *vi)
327 {
328 struct sk_buff *skb;
329 struct scatterlist sg[1];
330 int err;
331
332 if (!vi->mergeable_rx_bufs) {
333 try_fill_recv_maxbufs(vi);
334 return;
335 }
336
337 for (;;) {
338 skb_frag_t *f;
339
340 skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN);
341 if (unlikely(!skb))
342 break;
343
344 skb_reserve(skb, NET_IP_ALIGN);
345
346 f = &skb_shinfo(skb)->frags[0];
347 f->page = get_a_page(vi, GFP_ATOMIC);
348 if (!f->page) {
349 kfree_skb(skb);
350 break;
351 }
352
353 f->page_offset = 0;
354 f->size = PAGE_SIZE;
355
356 skb_shinfo(skb)->nr_frags++;
357
358 sg_init_one(sg, page_address(f->page), PAGE_SIZE);
359 skb_queue_head(&vi->recv, skb);
360
361 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb);
362 if (err) {
363 skb_unlink(skb, &vi->recv);
364 kfree_skb(skb);
365 break;
366 }
367 vi->num++;
368 }
369 if (unlikely(vi->num > vi->max))
370 vi->max = vi->num;
371 vi->rvq->vq_ops->kick(vi->rvq);
372 }
373
374 static void skb_recv_done(struct virtqueue *rvq)
375 {
376 struct virtnet_info *vi = rvq->vdev->priv;
377 /* Schedule NAPI, Suppress further interrupts if successful. */
378 if (netif_rx_schedule_prep(&vi->napi)) {
379 rvq->vq_ops->disable_cb(rvq);
380 __netif_rx_schedule(&vi->napi);
381 }
382 }
383
384 static int virtnet_poll(struct napi_struct *napi, int budget)
385 {
386 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
387 struct sk_buff *skb = NULL;
388 unsigned int len, received = 0;
389
390 again:
391 while (received < budget &&
392 (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
393 __skb_unlink(skb, &vi->recv);
394 receive_skb(vi->dev, skb, len);
395 vi->num--;
396 received++;
397 }
398
399 /* FIXME: If we oom and completely run out of inbufs, we need
400 * to start a timer trying to fill more. */
401 if (vi->num < vi->max / 2)
402 try_fill_recv(vi);
403
404 /* Out of packets? */
405 if (received < budget) {
406 netif_rx_complete(napi);
407 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
408 && napi_schedule_prep(napi)) {
409 vi->rvq->vq_ops->disable_cb(vi->rvq);
410 __netif_rx_schedule(napi);
411 goto again;
412 }
413 }
414
415 return received;
416 }
417
418 static void free_old_xmit_skbs(struct virtnet_info *vi)
419 {
420 struct sk_buff *skb;
421 unsigned int len;
422
423 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
424 pr_debug("Sent skb %p\n", skb);
425 __skb_unlink(skb, &vi->send);
426 vi->dev->stats.tx_bytes += skb->len;
427 vi->dev->stats.tx_packets++;
428 kfree_skb(skb);
429 }
430 }
431
432 /* If the virtio transport doesn't always notify us when all in-flight packets
433 * are consumed, we fall back to using this function on a timer to free them. */
434 static void xmit_free(unsigned long data)
435 {
436 struct virtnet_info *vi = (void *)data;
437
438 netif_tx_lock(vi->dev);
439
440 free_old_xmit_skbs(vi);
441
442 if (!skb_queue_empty(&vi->send))
443 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
444
445 netif_tx_unlock(vi->dev);
446 }
447
448 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
449 {
450 int num, err;
451 struct scatterlist sg[2+MAX_SKB_FRAGS];
452 struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
453 struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
454 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
455
456 sg_init_table(sg, 2+MAX_SKB_FRAGS);
457
458 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
459
460 if (skb->ip_summed == CHECKSUM_PARTIAL) {
461 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
462 hdr->csum_start = skb->csum_start - skb_headroom(skb);
463 hdr->csum_offset = skb->csum_offset;
464 } else {
465 hdr->flags = 0;
466 hdr->csum_offset = hdr->csum_start = 0;
467 }
468
469 if (skb_is_gso(skb)) {
470 hdr->hdr_len = skb_transport_header(skb) - skb->data;
471 hdr->gso_size = skb_shinfo(skb)->gso_size;
472 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
473 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
474 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
475 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
476 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
477 hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
478 else
479 BUG();
480 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
481 hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
482 } else {
483 hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
484 hdr->gso_size = hdr->hdr_len = 0;
485 }
486
487 mhdr->num_buffers = 0;
488
489 /* Encode metadata header at front. */
490 if (vi->mergeable_rx_bufs)
491 sg_set_buf(sg, mhdr, sizeof(*mhdr));
492 else
493 sg_set_buf(sg, hdr, sizeof(*hdr));
494
495 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
496
497 err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
498 if (!err && !vi->free_in_tasklet)
499 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
500
501 return err;
502 }
503
504 static void xmit_tasklet(unsigned long data)
505 {
506 struct virtnet_info *vi = (void *)data;
507
508 netif_tx_lock_bh(vi->dev);
509 if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) {
510 vi->svq->vq_ops->kick(vi->svq);
511 vi->last_xmit_skb = NULL;
512 }
513 if (vi->free_in_tasklet)
514 free_old_xmit_skbs(vi);
515 netif_tx_unlock_bh(vi->dev);
516 }
517
518 static int start_xmit(struct sk_buff *skb, struct net_device *dev)
519 {
520 struct virtnet_info *vi = netdev_priv(dev);
521
522 again:
523 /* Free up any pending old buffers before queueing new ones. */
524 free_old_xmit_skbs(vi);
525
526 /* If we has a buffer left over from last time, send it now. */
527 if (unlikely(vi->last_xmit_skb) &&
528 xmit_skb(vi, vi->last_xmit_skb) != 0)
529 goto stop_queue;
530
531 vi->last_xmit_skb = NULL;
532
533 /* Put new one in send queue and do transmit */
534 if (likely(skb)) {
535 __skb_queue_head(&vi->send, skb);
536 if (xmit_skb(vi, skb) != 0) {
537 vi->last_xmit_skb = skb;
538 skb = NULL;
539 goto stop_queue;
540 }
541 }
542 done:
543 vi->svq->vq_ops->kick(vi->svq);
544 return NETDEV_TX_OK;
545
546 stop_queue:
547 pr_debug("%s: virtio not prepared to send\n", dev->name);
548 netif_stop_queue(dev);
549
550 /* Activate callback for using skbs: if this returns false it
551 * means some were used in the meantime. */
552 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
553 vi->svq->vq_ops->disable_cb(vi->svq);
554 netif_start_queue(dev);
555 goto again;
556 }
557 if (skb) {
558 /* Drop this skb: we only queue one. */
559 vi->dev->stats.tx_dropped++;
560 kfree_skb(skb);
561 }
562 goto done;
563 }
564
565 #ifdef CONFIG_NET_POLL_CONTROLLER
566 static void virtnet_netpoll(struct net_device *dev)
567 {
568 struct virtnet_info *vi = netdev_priv(dev);
569
570 napi_schedule(&vi->napi);
571 }
572 #endif
573
574 static int virtnet_open(struct net_device *dev)
575 {
576 struct virtnet_info *vi = netdev_priv(dev);
577
578 napi_enable(&vi->napi);
579
580 /* If all buffers were filled by other side before we napi_enabled, we
581 * won't get another interrupt, so process any outstanding packets
582 * now. virtnet_poll wants re-enable the queue, so we disable here.
583 * We synchronize against interrupts via NAPI_STATE_SCHED */
584 if (netif_rx_schedule_prep(&vi->napi)) {
585 vi->rvq->vq_ops->disable_cb(vi->rvq);
586 __netif_rx_schedule(&vi->napi);
587 }
588 return 0;
589 }
590
591 static int virtnet_close(struct net_device *dev)
592 {
593 struct virtnet_info *vi = netdev_priv(dev);
594
595 napi_disable(&vi->napi);
596
597 return 0;
598 }
599
600 static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
601 {
602 struct virtnet_info *vi = netdev_priv(dev);
603 struct virtio_device *vdev = vi->vdev;
604
605 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
606 return -ENOSYS;
607
608 return ethtool_op_set_tx_hw_csum(dev, data);
609 }
610
611 static struct ethtool_ops virtnet_ethtool_ops = {
612 .set_tx_csum = virtnet_set_tx_csum,
613 .set_sg = ethtool_op_set_sg,
614 .set_tso = ethtool_op_set_tso,
615 };
616
617 #define MIN_MTU 68
618 #define MAX_MTU 65535
619
620 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
621 {
622 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
623 return -EINVAL;
624 dev->mtu = new_mtu;
625 return 0;
626 }
627
628 static const struct net_device_ops virtnet_netdev = {
629 .ndo_open = virtnet_open,
630 .ndo_stop = virtnet_close,
631 .ndo_start_xmit = start_xmit,
632 .ndo_validate_addr = eth_validate_addr,
633 .ndo_set_mac_address = eth_mac_addr,
634 .ndo_change_mtu = virtnet_change_mtu,
635 #ifdef CONFIG_NET_POLL_CONTROLLER
636 .ndo_poll_controller = virtnet_netpoll,
637 #endif
638 };
639
640 static int virtnet_probe(struct virtio_device *vdev)
641 {
642 int err;
643 struct net_device *dev;
644 struct virtnet_info *vi;
645
646 /* Allocate ourselves a network device with room for our info */
647 dev = alloc_etherdev(sizeof(struct virtnet_info));
648 if (!dev)
649 return -ENOMEM;
650
651 /* Set up network device as normal. */
652 dev->netdev_ops = &virtnet_netdev;
653 dev->features = NETIF_F_HIGHDMA;
654 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
655 SET_NETDEV_DEV(dev, &vdev->dev);
656
657 /* Do we support "hardware" checksums? */
658 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
659 /* This opens up the world of extra features. */
660 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
661 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
662 dev->features |= NETIF_F_TSO | NETIF_F_UFO
663 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
664 }
665 /* Individual feature bits: what can host handle? */
666 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
667 dev->features |= NETIF_F_TSO;
668 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
669 dev->features |= NETIF_F_TSO6;
670 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
671 dev->features |= NETIF_F_TSO_ECN;
672 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
673 dev->features |= NETIF_F_UFO;
674 }
675
676 /* Configuration may specify what MAC to use. Otherwise random. */
677 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
678 vdev->config->get(vdev,
679 offsetof(struct virtio_net_config, mac),
680 dev->dev_addr, dev->addr_len);
681 } else
682 random_ether_addr(dev->dev_addr);
683
684 /* Set up our device-specific information */
685 vi = netdev_priv(dev);
686 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
687 vi->dev = dev;
688 vi->vdev = vdev;
689 vdev->priv = vi;
690 vi->pages = NULL;
691
692 /* If they give us a callback when all buffers are done, we don't need
693 * the timer. */
694 vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY);
695
696 /* If we can receive ANY GSO packets, we must allocate large ones. */
697 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4)
698 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)
699 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
700 vi->big_packets = true;
701
702 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
703 vi->mergeable_rx_bufs = true;
704
705 /* We expect two virtqueues, receive then send. */
706 vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
707 if (IS_ERR(vi->rvq)) {
708 err = PTR_ERR(vi->rvq);
709 goto free;
710 }
711
712 vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
713 if (IS_ERR(vi->svq)) {
714 err = PTR_ERR(vi->svq);
715 goto free_recv;
716 }
717
718 /* Initialize our empty receive and send queues. */
719 skb_queue_head_init(&vi->recv);
720 skb_queue_head_init(&vi->send);
721
722 tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi);
723
724 if (!vi->free_in_tasklet)
725 setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
726
727 err = register_netdev(dev);
728 if (err) {
729 pr_debug("virtio_net: registering device failed\n");
730 goto free_send;
731 }
732
733 /* Last of all, set up some receive buffers. */
734 try_fill_recv(vi);
735
736 /* If we didn't even get one input buffer, we're useless. */
737 if (vi->num == 0) {
738 err = -ENOMEM;
739 goto unregister;
740 }
741
742 pr_debug("virtnet: registered device %s\n", dev->name);
743 return 0;
744
745 unregister:
746 unregister_netdev(dev);
747 free_send:
748 vdev->config->del_vq(vi->svq);
749 free_recv:
750 vdev->config->del_vq(vi->rvq);
751 free:
752 free_netdev(dev);
753 return err;
754 }
755
756 static void virtnet_remove(struct virtio_device *vdev)
757 {
758 struct virtnet_info *vi = vdev->priv;
759 struct sk_buff *skb;
760
761 /* Stop all the virtqueues. */
762 vdev->config->reset(vdev);
763
764 if (!vi->free_in_tasklet)
765 del_timer_sync(&vi->xmit_free_timer);
766
767 /* Free our skbs in send and recv queues, if any. */
768 while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
769 kfree_skb(skb);
770 vi->num--;
771 }
772 __skb_queue_purge(&vi->send);
773
774 BUG_ON(vi->num != 0);
775
776 vdev->config->del_vq(vi->svq);
777 vdev->config->del_vq(vi->rvq);
778 unregister_netdev(vi->dev);
779
780 while (vi->pages)
781 __free_pages(get_a_page(vi, GFP_KERNEL), 0);
782
783 free_netdev(vi->dev);
784 }
785
786 static struct virtio_device_id id_table[] = {
787 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
788 { 0 },
789 };
790
791 static unsigned int features[] = {
792 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
793 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
794 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
795 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
796 VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */
797 VIRTIO_NET_F_MRG_RXBUF,
798 VIRTIO_F_NOTIFY_ON_EMPTY,
799 };
800
801 static struct virtio_driver virtio_net = {
802 .feature_table = features,
803 .feature_table_size = ARRAY_SIZE(features),
804 .driver.name = KBUILD_MODNAME,
805 .driver.owner = THIS_MODULE,
806 .id_table = id_table,
807 .probe = virtnet_probe,
808 .remove = __devexit_p(virtnet_remove),
809 };
810
811 static int __init init(void)
812 {
813 return register_virtio_driver(&virtio_net);
814 }
815
816 static void __exit fini(void)
817 {
818 unregister_virtio_driver(&virtio_net);
819 }
820 module_init(init);
821 module_exit(fini);
822
823 MODULE_DEVICE_TABLE(virtio, id_table);
824 MODULE_DESCRIPTION("Virtio network driver");
825 MODULE_LICENSE("GPL");
Linus' kernel tree