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296f96fc RR |
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> | |
a9ea3fc6 | 22 | #include <linux/ethtool.h> |
296f96fc RR |
23 | #include <linux/module.h> |
24 | #include <linux/virtio.h> | |
25 | #include <linux/virtio_net.h> | |
26 | #include <linux/scatterlist.h> | |
e918085a | 27 | #include <linux/if_vlan.h> |
296f96fc | 28 | |
6c0cd7c0 DL |
29 | static int napi_weight = 128; |
30 | module_param(napi_weight, int, 0444); | |
31 | ||
34a48579 RR |
32 | static int csum = 1, gso = 1; |
33 | module_param(csum, bool, 0444); | |
34 | module_param(gso, bool, 0444); | |
35 | ||
296f96fc | 36 | /* FIXME: MTU in config. */ |
e918085a | 37 | #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) |
3f2c31d9 | 38 | #define GOOD_COPY_LEN 128 |
296f96fc RR |
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; | |
9f4d26d0 | 46 | unsigned int status; |
296f96fc | 47 | |
99ffc696 RR |
48 | /* The skb we couldn't send because buffers were full. */ |
49 | struct sk_buff *last_xmit_skb; | |
50 | ||
363f1514 | 51 | /* If we need to free in a timer, this is it. */ |
14c998f0 MM |
52 | struct timer_list xmit_free_timer; |
53 | ||
296f96fc RR |
54 | /* Number of input buffers, and max we've ever had. */ |
55 | unsigned int num, max; | |
56 | ||
11a3a154 RR |
57 | /* For cleaning up after transmission. */ |
58 | struct tasklet_struct tasklet; | |
363f1514 | 59 | bool free_in_tasklet; |
11a3a154 | 60 | |
97402b96 HX |
61 | /* I like... big packets and I cannot lie! */ |
62 | bool big_packets; | |
63 | ||
3f2c31d9 MM |
64 | /* Host will merge rx buffers for big packets (shake it! shake it!) */ |
65 | bool mergeable_rx_bufs; | |
66 | ||
296f96fc RR |
67 | /* Receive & send queues. */ |
68 | struct sk_buff_head recv; | |
69 | struct sk_buff_head send; | |
fb6813f4 RR |
70 | |
71 | /* Chain pages by the private ptr. */ | |
72 | struct page *pages; | |
296f96fc RR |
73 | }; |
74 | ||
3f2c31d9 | 75 | static inline void *skb_vnet_hdr(struct sk_buff *skb) |
296f96fc RR |
76 | { |
77 | return (struct virtio_net_hdr *)skb->cb; | |
78 | } | |
79 | ||
fb6813f4 RR |
80 | static void give_a_page(struct virtnet_info *vi, struct page *page) |
81 | { | |
82 | page->private = (unsigned long)vi->pages; | |
83 | vi->pages = page; | |
84 | } | |
85 | ||
0a888fd1 MM |
86 | static void trim_pages(struct virtnet_info *vi, struct sk_buff *skb) |
87 | { | |
88 | unsigned int i; | |
89 | ||
90 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) | |
91 | give_a_page(vi, skb_shinfo(skb)->frags[i].page); | |
92 | skb_shinfo(skb)->nr_frags = 0; | |
93 | skb->data_len = 0; | |
94 | } | |
95 | ||
fb6813f4 RR |
96 | static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask) |
97 | { | |
98 | struct page *p = vi->pages; | |
99 | ||
100 | if (p) | |
101 | vi->pages = (struct page *)p->private; | |
102 | else | |
103 | p = alloc_page(gfp_mask); | |
104 | return p; | |
105 | } | |
106 | ||
2cb9c6ba | 107 | static void skb_xmit_done(struct virtqueue *svq) |
296f96fc | 108 | { |
2cb9c6ba | 109 | struct virtnet_info *vi = svq->vdev->priv; |
296f96fc | 110 | |
2cb9c6ba RR |
111 | /* Suppress further interrupts. */ |
112 | svq->vq_ops->disable_cb(svq); | |
11a3a154 | 113 | |
363f1514 | 114 | /* We were probably waiting for more output buffers. */ |
296f96fc | 115 | netif_wake_queue(vi->dev); |
11a3a154 RR |
116 | |
117 | /* Make sure we re-xmit last_xmit_skb: if there are no more packets | |
118 | * queued, start_xmit won't be called. */ | |
119 | tasklet_schedule(&vi->tasklet); | |
296f96fc RR |
120 | } |
121 | ||
122 | static void receive_skb(struct net_device *dev, struct sk_buff *skb, | |
123 | unsigned len) | |
124 | { | |
3f2c31d9 | 125 | struct virtnet_info *vi = netdev_priv(dev); |
296f96fc | 126 | struct virtio_net_hdr *hdr = skb_vnet_hdr(skb); |
97402b96 | 127 | int err; |
3f2c31d9 | 128 | int i; |
296f96fc RR |
129 | |
130 | if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) { | |
131 | pr_debug("%s: short packet %i\n", dev->name, len); | |
132 | dev->stats.rx_length_errors++; | |
133 | goto drop; | |
134 | } | |
23cde76d | 135 | |
3f2c31d9 MM |
136 | if (vi->mergeable_rx_bufs) { |
137 | struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb); | |
138 | unsigned int copy; | |
139 | char *p = page_address(skb_shinfo(skb)->frags[0].page); | |
fb6813f4 | 140 | |
3f2c31d9 MM |
141 | if (len > PAGE_SIZE) |
142 | len = PAGE_SIZE; | |
143 | len -= sizeof(struct virtio_net_hdr_mrg_rxbuf); | |
144 | ||
145 | memcpy(hdr, p, sizeof(*mhdr)); | |
146 | p += sizeof(*mhdr); | |
147 | ||
148 | copy = len; | |
149 | if (copy > skb_tailroom(skb)) | |
150 | copy = skb_tailroom(skb); | |
151 | ||
152 | memcpy(skb_put(skb, copy), p, copy); | |
153 | ||
154 | len -= copy; | |
155 | ||
156 | if (!len) { | |
157 | give_a_page(vi, skb_shinfo(skb)->frags[0].page); | |
158 | skb_shinfo(skb)->nr_frags--; | |
159 | } else { | |
160 | skb_shinfo(skb)->frags[0].page_offset += | |
161 | sizeof(*mhdr) + copy; | |
162 | skb_shinfo(skb)->frags[0].size = len; | |
163 | skb->data_len += len; | |
164 | skb->len += len; | |
165 | } | |
166 | ||
167 | while (--mhdr->num_buffers) { | |
168 | struct sk_buff *nskb; | |
169 | ||
170 | i = skb_shinfo(skb)->nr_frags; | |
171 | if (i >= MAX_SKB_FRAGS) { | |
172 | pr_debug("%s: packet too long %d\n", dev->name, | |
173 | len); | |
174 | dev->stats.rx_length_errors++; | |
175 | goto drop; | |
176 | } | |
177 | ||
178 | nskb = vi->rvq->vq_ops->get_buf(vi->rvq, &len); | |
179 | if (!nskb) { | |
180 | pr_debug("%s: rx error: %d buffers missing\n", | |
181 | dev->name, mhdr->num_buffers); | |
182 | dev->stats.rx_length_errors++; | |
183 | goto drop; | |
184 | } | |
185 | ||
186 | __skb_unlink(nskb, &vi->recv); | |
187 | vi->num--; | |
188 | ||
189 | skb_shinfo(skb)->frags[i] = skb_shinfo(nskb)->frags[0]; | |
190 | skb_shinfo(nskb)->nr_frags = 0; | |
191 | kfree_skb(nskb); | |
192 | ||
193 | if (len > PAGE_SIZE) | |
194 | len = PAGE_SIZE; | |
195 | ||
196 | skb_shinfo(skb)->frags[i].size = len; | |
197 | skb_shinfo(skb)->nr_frags++; | |
198 | skb->data_len += len; | |
199 | skb->len += len; | |
200 | } | |
201 | } else { | |
202 | len -= sizeof(struct virtio_net_hdr); | |
203 | ||
204 | if (len <= MAX_PACKET_LEN) | |
205 | trim_pages(vi, skb); | |
206 | ||
207 | err = pskb_trim(skb, len); | |
208 | if (err) { | |
209 | pr_debug("%s: pskb_trim failed %i %d\n", dev->name, | |
210 | len, err); | |
211 | dev->stats.rx_dropped++; | |
212 | goto drop; | |
213 | } | |
97402b96 | 214 | } |
3f2c31d9 | 215 | |
97402b96 | 216 | skb->truesize += skb->data_len; |
296f96fc RR |
217 | dev->stats.rx_bytes += skb->len; |
218 | dev->stats.rx_packets++; | |
219 | ||
220 | if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { | |
221 | pr_debug("Needs csum!\n"); | |
f35d9d8a | 222 | if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset)) |
296f96fc | 223 | goto frame_err; |
296f96fc RR |
224 | } |
225 | ||
23cde76d MM |
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 | ||
296f96fc RR |
230 | if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) { |
231 | pr_debug("GSO!\n"); | |
34a48579 | 232 | switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { |
296f96fc RR |
233 | case VIRTIO_NET_HDR_GSO_TCPV4: |
234 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; | |
235 | break; | |
296f96fc RR |
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->gso_type); | |
246 | goto frame_err; | |
247 | } | |
248 | ||
34a48579 RR |
249 | if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) |
250 | skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; | |
251 | ||
296f96fc RR |
252 | skb_shinfo(skb)->gso_size = 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 | ||
3f2c31d9 | 274 | static void try_fill_recv_maxbufs(struct virtnet_info *vi) |
296f96fc RR |
275 | { |
276 | struct sk_buff *skb; | |
05271685 | 277 | struct scatterlist sg[2+MAX_SKB_FRAGS]; |
97402b96 | 278 | int num, err, i; |
296f96fc | 279 | |
05271685 | 280 | sg_init_table(sg, 2+MAX_SKB_FRAGS); |
296f96fc | 281 | for (;;) { |
3f2c31d9 MM |
282 | struct virtio_net_hdr *hdr; |
283 | ||
296f96fc RR |
284 | skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN); |
285 | if (unlikely(!skb)) | |
286 | break; | |
287 | ||
288 | skb_put(skb, MAX_PACKET_LEN); | |
3f2c31d9 MM |
289 | |
290 | hdr = skb_vnet_hdr(skb); | |
8527bec5 | 291 | sg_set_buf(sg, hdr, sizeof(*hdr)); |
97402b96 HX |
292 | |
293 | if (vi->big_packets) { | |
294 | for (i = 0; i < MAX_SKB_FRAGS; i++) { | |
295 | skb_frag_t *f = &skb_shinfo(skb)->frags[i]; | |
fb6813f4 | 296 | f->page = get_a_page(vi, GFP_ATOMIC); |
97402b96 HX |
297 | if (!f->page) |
298 | break; | |
299 | ||
300 | f->page_offset = 0; | |
301 | f->size = PAGE_SIZE; | |
302 | ||
303 | skb->data_len += PAGE_SIZE; | |
304 | skb->len += PAGE_SIZE; | |
305 | ||
306 | skb_shinfo(skb)->nr_frags++; | |
307 | } | |
308 | } | |
309 | ||
296f96fc RR |
310 | num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; |
311 | skb_queue_head(&vi->recv, skb); | |
312 | ||
313 | err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb); | |
314 | if (err) { | |
315 | skb_unlink(skb, &vi->recv); | |
0a888fd1 | 316 | trim_pages(vi, skb); |
296f96fc RR |
317 | kfree_skb(skb); |
318 | break; | |
319 | } | |
320 | vi->num++; | |
321 | } | |
322 | if (unlikely(vi->num > vi->max)) | |
323 | vi->max = vi->num; | |
324 | vi->rvq->vq_ops->kick(vi->rvq); | |
325 | } | |
326 | ||
3f2c31d9 MM |
327 | static void try_fill_recv(struct virtnet_info *vi) |
328 | { | |
329 | struct sk_buff *skb; | |
330 | struct scatterlist sg[1]; | |
331 | int err; | |
332 | ||
333 | if (!vi->mergeable_rx_bufs) { | |
334 | try_fill_recv_maxbufs(vi); | |
335 | return; | |
336 | } | |
337 | ||
338 | for (;;) { | |
339 | skb_frag_t *f; | |
340 | ||
341 | skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN); | |
342 | if (unlikely(!skb)) | |
343 | break; | |
344 | ||
345 | skb_reserve(skb, NET_IP_ALIGN); | |
346 | ||
347 | f = &skb_shinfo(skb)->frags[0]; | |
348 | f->page = get_a_page(vi, GFP_ATOMIC); | |
349 | if (!f->page) { | |
350 | kfree_skb(skb); | |
351 | break; | |
352 | } | |
353 | ||
354 | f->page_offset = 0; | |
355 | f->size = PAGE_SIZE; | |
356 | ||
357 | skb_shinfo(skb)->nr_frags++; | |
358 | ||
359 | sg_init_one(sg, page_address(f->page), PAGE_SIZE); | |
360 | skb_queue_head(&vi->recv, skb); | |
361 | ||
362 | err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb); | |
363 | if (err) { | |
364 | skb_unlink(skb, &vi->recv); | |
365 | kfree_skb(skb); | |
366 | break; | |
367 | } | |
368 | vi->num++; | |
369 | } | |
370 | if (unlikely(vi->num > vi->max)) | |
371 | vi->max = vi->num; | |
372 | vi->rvq->vq_ops->kick(vi->rvq); | |
373 | } | |
374 | ||
18445c4d | 375 | static void skb_recv_done(struct virtqueue *rvq) |
296f96fc RR |
376 | { |
377 | struct virtnet_info *vi = rvq->vdev->priv; | |
18445c4d | 378 | /* Schedule NAPI, Suppress further interrupts if successful. */ |
288379f0 | 379 | if (napi_schedule_prep(&vi->napi)) { |
18445c4d | 380 | rvq->vq_ops->disable_cb(rvq); |
288379f0 | 381 | __napi_schedule(&vi->napi); |
18445c4d | 382 | } |
296f96fc RR |
383 | } |
384 | ||
385 | static int virtnet_poll(struct napi_struct *napi, int budget) | |
386 | { | |
387 | struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi); | |
388 | struct sk_buff *skb = NULL; | |
389 | unsigned int len, received = 0; | |
390 | ||
391 | again: | |
392 | while (received < budget && | |
393 | (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) { | |
394 | __skb_unlink(skb, &vi->recv); | |
395 | receive_skb(vi->dev, skb, len); | |
396 | vi->num--; | |
397 | received++; | |
398 | } | |
399 | ||
400 | /* FIXME: If we oom and completely run out of inbufs, we need | |
401 | * to start a timer trying to fill more. */ | |
402 | if (vi->num < vi->max / 2) | |
403 | try_fill_recv(vi); | |
404 | ||
8329d98e RR |
405 | /* Out of packets? */ |
406 | if (received < budget) { | |
288379f0 | 407 | napi_complete(napi); |
18445c4d | 408 | if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) |
4265f161 CB |
409 | && napi_schedule_prep(napi)) { |
410 | vi->rvq->vq_ops->disable_cb(vi->rvq); | |
288379f0 | 411 | __napi_schedule(napi); |
296f96fc | 412 | goto again; |
4265f161 | 413 | } |
296f96fc RR |
414 | } |
415 | ||
416 | return received; | |
417 | } | |
418 | ||
419 | static void free_old_xmit_skbs(struct virtnet_info *vi) | |
420 | { | |
421 | struct sk_buff *skb; | |
422 | unsigned int len; | |
423 | ||
424 | while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) { | |
425 | pr_debug("Sent skb %p\n", skb); | |
426 | __skb_unlink(skb, &vi->send); | |
655aa31f | 427 | vi->dev->stats.tx_bytes += skb->len; |
296f96fc RR |
428 | vi->dev->stats.tx_packets++; |
429 | kfree_skb(skb); | |
430 | } | |
431 | } | |
432 | ||
363f1514 RR |
433 | /* If the virtio transport doesn't always notify us when all in-flight packets |
434 | * are consumed, we fall back to using this function on a timer to free them. */ | |
14c998f0 MM |
435 | static void xmit_free(unsigned long data) |
436 | { | |
437 | struct virtnet_info *vi = (void *)data; | |
438 | ||
439 | netif_tx_lock(vi->dev); | |
440 | ||
441 | free_old_xmit_skbs(vi); | |
442 | ||
443 | if (!skb_queue_empty(&vi->send)) | |
444 | mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10)); | |
445 | ||
446 | netif_tx_unlock(vi->dev); | |
447 | } | |
448 | ||
99ffc696 | 449 | static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) |
296f96fc | 450 | { |
14c998f0 | 451 | int num, err; |
05271685 | 452 | struct scatterlist sg[2+MAX_SKB_FRAGS]; |
3f2c31d9 MM |
453 | struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb); |
454 | struct virtio_net_hdr *hdr = skb_vnet_hdr(skb); | |
296f96fc | 455 | const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; |
296f96fc | 456 | |
05271685 | 457 | sg_init_table(sg, 2+MAX_SKB_FRAGS); |
4d125de3 | 458 | |
e174961c | 459 | pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest); |
296f96fc | 460 | |
296f96fc RR |
461 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
462 | hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; | |
463 | hdr->csum_start = skb->csum_start - skb_headroom(skb); | |
464 | hdr->csum_offset = skb->csum_offset; | |
465 | } else { | |
466 | hdr->flags = 0; | |
467 | hdr->csum_offset = hdr->csum_start = 0; | |
468 | } | |
469 | ||
470 | if (skb_is_gso(skb)) { | |
50c8ea80 | 471 | hdr->hdr_len = skb_transport_header(skb) - skb->data; |
296f96fc | 472 | hdr->gso_size = skb_shinfo(skb)->gso_size; |
34a48579 | 473 | if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) |
296f96fc RR |
474 | hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; |
475 | else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) | |
476 | hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; | |
477 | else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP) | |
478 | hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP; | |
479 | else | |
480 | BUG(); | |
34a48579 RR |
481 | if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN) |
482 | hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; | |
296f96fc RR |
483 | } else { |
484 | hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE; | |
50c8ea80 | 485 | hdr->gso_size = hdr->hdr_len = 0; |
296f96fc RR |
486 | } |
487 | ||
3f2c31d9 MM |
488 | mhdr->num_buffers = 0; |
489 | ||
490 | /* Encode metadata header at front. */ | |
491 | if (vi->mergeable_rx_bufs) | |
8527bec5 | 492 | sg_set_buf(sg, mhdr, sizeof(*mhdr)); |
3f2c31d9 | 493 | else |
8527bec5 | 494 | sg_set_buf(sg, hdr, sizeof(*hdr)); |
3f2c31d9 | 495 | |
296f96fc | 496 | num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; |
99ffc696 | 497 | |
14c998f0 | 498 | err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb); |
363f1514 | 499 | if (!err && !vi->free_in_tasklet) |
14c998f0 MM |
500 | mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10)); |
501 | ||
502 | return err; | |
99ffc696 RR |
503 | } |
504 | ||
11a3a154 RR |
505 | static void xmit_tasklet(unsigned long data) |
506 | { | |
507 | struct virtnet_info *vi = (void *)data; | |
508 | ||
509 | netif_tx_lock_bh(vi->dev); | |
510 | if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) { | |
511 | vi->svq->vq_ops->kick(vi->svq); | |
512 | vi->last_xmit_skb = NULL; | |
513 | } | |
363f1514 RR |
514 | if (vi->free_in_tasklet) |
515 | free_old_xmit_skbs(vi); | |
11a3a154 RR |
516 | netif_tx_unlock_bh(vi->dev); |
517 | } | |
518 | ||
99ffc696 RR |
519 | static int start_xmit(struct sk_buff *skb, struct net_device *dev) |
520 | { | |
521 | struct virtnet_info *vi = netdev_priv(dev); | |
2cb9c6ba RR |
522 | |
523 | again: | |
524 | /* Free up any pending old buffers before queueing new ones. */ | |
525 | free_old_xmit_skbs(vi); | |
99ffc696 RR |
526 | |
527 | /* If we has a buffer left over from last time, send it now. */ | |
9953ca6c MM |
528 | if (unlikely(vi->last_xmit_skb) && |
529 | xmit_skb(vi, vi->last_xmit_skb) != 0) | |
530 | goto stop_queue; | |
531 | ||
532 | vi->last_xmit_skb = NULL; | |
2cb9c6ba | 533 | |
99ffc696 | 534 | /* Put new one in send queue and do transmit */ |
7eb2e251 RR |
535 | if (likely(skb)) { |
536 | __skb_queue_head(&vi->send, skb); | |
537 | if (xmit_skb(vi, skb) != 0) { | |
538 | vi->last_xmit_skb = skb; | |
539 | skb = NULL; | |
540 | goto stop_queue; | |
541 | } | |
296f96fc | 542 | } |
99ffc696 | 543 | done: |
296f96fc | 544 | vi->svq->vq_ops->kick(vi->svq); |
99ffc696 RR |
545 | return NETDEV_TX_OK; |
546 | ||
547 | stop_queue: | |
548 | pr_debug("%s: virtio not prepared to send\n", dev->name); | |
549 | netif_stop_queue(dev); | |
550 | ||
551 | /* Activate callback for using skbs: if this returns false it | |
552 | * means some were used in the meantime. */ | |
553 | if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) { | |
554 | vi->svq->vq_ops->disable_cb(vi->svq); | |
555 | netif_start_queue(dev); | |
556 | goto again; | |
557 | } | |
9953ca6c MM |
558 | if (skb) { |
559 | /* Drop this skb: we only queue one. */ | |
560 | vi->dev->stats.tx_dropped++; | |
561 | kfree_skb(skb); | |
562 | } | |
99ffc696 | 563 | goto done; |
296f96fc RR |
564 | } |
565 | ||
da74e89d AS |
566 | #ifdef CONFIG_NET_POLL_CONTROLLER |
567 | static void virtnet_netpoll(struct net_device *dev) | |
568 | { | |
569 | struct virtnet_info *vi = netdev_priv(dev); | |
570 | ||
571 | napi_schedule(&vi->napi); | |
572 | } | |
573 | #endif | |
574 | ||
296f96fc RR |
575 | static int virtnet_open(struct net_device *dev) |
576 | { | |
577 | struct virtnet_info *vi = netdev_priv(dev); | |
578 | ||
296f96fc | 579 | napi_enable(&vi->napi); |
a48bd8f6 RR |
580 | |
581 | /* If all buffers were filled by other side before we napi_enabled, we | |
582 | * won't get another interrupt, so process any outstanding packets | |
370076d9 CB |
583 | * now. virtnet_poll wants re-enable the queue, so we disable here. |
584 | * We synchronize against interrupts via NAPI_STATE_SCHED */ | |
288379f0 | 585 | if (napi_schedule_prep(&vi->napi)) { |
370076d9 | 586 | vi->rvq->vq_ops->disable_cb(vi->rvq); |
288379f0 | 587 | __napi_schedule(&vi->napi); |
370076d9 | 588 | } |
296f96fc RR |
589 | return 0; |
590 | } | |
591 | ||
592 | static int virtnet_close(struct net_device *dev) | |
593 | { | |
594 | struct virtnet_info *vi = netdev_priv(dev); | |
296f96fc RR |
595 | |
596 | napi_disable(&vi->napi); | |
597 | ||
296f96fc RR |
598 | return 0; |
599 | } | |
600 | ||
a9ea3fc6 HX |
601 | static int virtnet_set_tx_csum(struct net_device *dev, u32 data) |
602 | { | |
603 | struct virtnet_info *vi = netdev_priv(dev); | |
604 | struct virtio_device *vdev = vi->vdev; | |
605 | ||
606 | if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) | |
607 | return -ENOSYS; | |
608 | ||
609 | return ethtool_op_set_tx_hw_csum(dev, data); | |
610 | } | |
611 | ||
612 | static struct ethtool_ops virtnet_ethtool_ops = { | |
613 | .set_tx_csum = virtnet_set_tx_csum, | |
614 | .set_sg = ethtool_op_set_sg, | |
0276b497 | 615 | .set_tso = ethtool_op_set_tso, |
9f4d26d0 | 616 | .get_link = ethtool_op_get_link, |
a9ea3fc6 HX |
617 | }; |
618 | ||
39da5814 MM |
619 | #define MIN_MTU 68 |
620 | #define MAX_MTU 65535 | |
621 | ||
622 | static int virtnet_change_mtu(struct net_device *dev, int new_mtu) | |
623 | { | |
624 | if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) | |
625 | return -EINVAL; | |
626 | dev->mtu = new_mtu; | |
627 | return 0; | |
628 | } | |
629 | ||
76288b4e SH |
630 | static const struct net_device_ops virtnet_netdev = { |
631 | .ndo_open = virtnet_open, | |
632 | .ndo_stop = virtnet_close, | |
633 | .ndo_start_xmit = start_xmit, | |
634 | .ndo_validate_addr = eth_validate_addr, | |
635 | .ndo_set_mac_address = eth_mac_addr, | |
636 | .ndo_change_mtu = virtnet_change_mtu, | |
637 | #ifdef CONFIG_NET_POLL_CONTROLLER | |
638 | .ndo_poll_controller = virtnet_netpoll, | |
639 | #endif | |
640 | }; | |
641 | ||
9f4d26d0 MM |
642 | static void virtnet_update_status(struct virtnet_info *vi) |
643 | { | |
644 | u16 v; | |
645 | ||
646 | if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) | |
647 | return; | |
648 | ||
649 | vi->vdev->config->get(vi->vdev, | |
650 | offsetof(struct virtio_net_config, status), | |
651 | &v, sizeof(v)); | |
652 | ||
653 | /* Ignore unknown (future) status bits */ | |
654 | v &= VIRTIO_NET_S_LINK_UP; | |
655 | ||
656 | if (vi->status == v) | |
657 | return; | |
658 | ||
659 | vi->status = v; | |
660 | ||
661 | if (vi->status & VIRTIO_NET_S_LINK_UP) { | |
662 | netif_carrier_on(vi->dev); | |
663 | netif_wake_queue(vi->dev); | |
664 | } else { | |
665 | netif_carrier_off(vi->dev); | |
666 | netif_stop_queue(vi->dev); | |
667 | } | |
668 | } | |
669 | ||
670 | static void virtnet_config_changed(struct virtio_device *vdev) | |
671 | { | |
672 | struct virtnet_info *vi = vdev->priv; | |
673 | ||
674 | virtnet_update_status(vi); | |
675 | } | |
676 | ||
296f96fc RR |
677 | static int virtnet_probe(struct virtio_device *vdev) |
678 | { | |
679 | int err; | |
296f96fc RR |
680 | struct net_device *dev; |
681 | struct virtnet_info *vi; | |
296f96fc RR |
682 | |
683 | /* Allocate ourselves a network device with room for our info */ | |
684 | dev = alloc_etherdev(sizeof(struct virtnet_info)); | |
685 | if (!dev) | |
686 | return -ENOMEM; | |
687 | ||
688 | /* Set up network device as normal. */ | |
76288b4e | 689 | dev->netdev_ops = &virtnet_netdev; |
296f96fc | 690 | dev->features = NETIF_F_HIGHDMA; |
a9ea3fc6 | 691 | SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops); |
296f96fc RR |
692 | SET_NETDEV_DEV(dev, &vdev->dev); |
693 | ||
694 | /* Do we support "hardware" checksums? */ | |
c45a6816 | 695 | if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { |
296f96fc RR |
696 | /* This opens up the world of extra features. */ |
697 | dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; | |
c45a6816 | 698 | if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { |
34a48579 RR |
699 | dev->features |= NETIF_F_TSO | NETIF_F_UFO |
700 | | NETIF_F_TSO_ECN | NETIF_F_TSO6; | |
701 | } | |
5539ae96 | 702 | /* Individual feature bits: what can host handle? */ |
c45a6816 | 703 | if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4)) |
5539ae96 | 704 | dev->features |= NETIF_F_TSO; |
c45a6816 | 705 | if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6)) |
5539ae96 | 706 | dev->features |= NETIF_F_TSO6; |
c45a6816 | 707 | if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN)) |
5539ae96 | 708 | dev->features |= NETIF_F_TSO_ECN; |
c45a6816 | 709 | if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO)) |
5539ae96 | 710 | dev->features |= NETIF_F_UFO; |
296f96fc RR |
711 | } |
712 | ||
713 | /* Configuration may specify what MAC to use. Otherwise random. */ | |
c45a6816 | 714 | if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) { |
a586d4f6 RR |
715 | vdev->config->get(vdev, |
716 | offsetof(struct virtio_net_config, mac), | |
717 | dev->dev_addr, dev->addr_len); | |
296f96fc RR |
718 | } else |
719 | random_ether_addr(dev->dev_addr); | |
720 | ||
721 | /* Set up our device-specific information */ | |
722 | vi = netdev_priv(dev); | |
6c0cd7c0 | 723 | netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight); |
296f96fc RR |
724 | vi->dev = dev; |
725 | vi->vdev = vdev; | |
d9d5dcc8 | 726 | vdev->priv = vi; |
fb6813f4 | 727 | vi->pages = NULL; |
296f96fc | 728 | |
363f1514 RR |
729 | /* If they give us a callback when all buffers are done, we don't need |
730 | * the timer. */ | |
731 | vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY); | |
732 | ||
97402b96 HX |
733 | /* If we can receive ANY GSO packets, we must allocate large ones. */ |
734 | if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) | |
735 | || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) | |
736 | || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN)) | |
737 | vi->big_packets = true; | |
738 | ||
3f2c31d9 MM |
739 | if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) |
740 | vi->mergeable_rx_bufs = true; | |
741 | ||
296f96fc | 742 | /* We expect two virtqueues, receive then send. */ |
a586d4f6 | 743 | vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done); |
296f96fc RR |
744 | if (IS_ERR(vi->rvq)) { |
745 | err = PTR_ERR(vi->rvq); | |
746 | goto free; | |
747 | } | |
748 | ||
a586d4f6 | 749 | vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done); |
296f96fc RR |
750 | if (IS_ERR(vi->svq)) { |
751 | err = PTR_ERR(vi->svq); | |
752 | goto free_recv; | |
753 | } | |
754 | ||
755 | /* Initialize our empty receive and send queues. */ | |
756 | skb_queue_head_init(&vi->recv); | |
757 | skb_queue_head_init(&vi->send); | |
758 | ||
11a3a154 RR |
759 | tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi); |
760 | ||
363f1514 RR |
761 | if (!vi->free_in_tasklet) |
762 | setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi); | |
14c998f0 | 763 | |
296f96fc RR |
764 | err = register_netdev(dev); |
765 | if (err) { | |
766 | pr_debug("virtio_net: registering device failed\n"); | |
767 | goto free_send; | |
768 | } | |
b3369c1f RR |
769 | |
770 | /* Last of all, set up some receive buffers. */ | |
771 | try_fill_recv(vi); | |
772 | ||
773 | /* If we didn't even get one input buffer, we're useless. */ | |
774 | if (vi->num == 0) { | |
775 | err = -ENOMEM; | |
776 | goto unregister; | |
777 | } | |
778 | ||
9f4d26d0 MM |
779 | vi->status = VIRTIO_NET_S_LINK_UP; |
780 | virtnet_update_status(vi); | |
781 | ||
296f96fc | 782 | pr_debug("virtnet: registered device %s\n", dev->name); |
296f96fc RR |
783 | return 0; |
784 | ||
b3369c1f RR |
785 | unregister: |
786 | unregister_netdev(dev); | |
296f96fc RR |
787 | free_send: |
788 | vdev->config->del_vq(vi->svq); | |
789 | free_recv: | |
790 | vdev->config->del_vq(vi->rvq); | |
791 | free: | |
792 | free_netdev(dev); | |
793 | return err; | |
794 | } | |
795 | ||
796 | static void virtnet_remove(struct virtio_device *vdev) | |
797 | { | |
74b2553f | 798 | struct virtnet_info *vi = vdev->priv; |
b3369c1f RR |
799 | struct sk_buff *skb; |
800 | ||
6e5aa7ef RR |
801 | /* Stop all the virtqueues. */ |
802 | vdev->config->reset(vdev); | |
803 | ||
363f1514 RR |
804 | if (!vi->free_in_tasklet) |
805 | del_timer_sync(&vi->xmit_free_timer); | |
14c998f0 | 806 | |
b3369c1f | 807 | /* Free our skbs in send and recv queues, if any. */ |
b3369c1f RR |
808 | while ((skb = __skb_dequeue(&vi->recv)) != NULL) { |
809 | kfree_skb(skb); | |
810 | vi->num--; | |
811 | } | |
288369cc | 812 | __skb_queue_purge(&vi->send); |
b3369c1f RR |
813 | |
814 | BUG_ON(vi->num != 0); | |
74b2553f RR |
815 | |
816 | vdev->config->del_vq(vi->svq); | |
817 | vdev->config->del_vq(vi->rvq); | |
818 | unregister_netdev(vi->dev); | |
fb6813f4 RR |
819 | |
820 | while (vi->pages) | |
821 | __free_pages(get_a_page(vi, GFP_KERNEL), 0); | |
822 | ||
74b2553f | 823 | free_netdev(vi->dev); |
296f96fc RR |
824 | } |
825 | ||
826 | static struct virtio_device_id id_table[] = { | |
827 | { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, | |
828 | { 0 }, | |
829 | }; | |
830 | ||
c45a6816 | 831 | static unsigned int features[] = { |
5e4fe5c4 MM |
832 | VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, |
833 | VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC, | |
c45a6816 | 834 | VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, |
97402b96 HX |
835 | VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, |
836 | VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */ | |
9f4d26d0 | 837 | VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, |
97402b96 | 838 | VIRTIO_F_NOTIFY_ON_EMPTY, |
c45a6816 RR |
839 | }; |
840 | ||
296f96fc | 841 | static struct virtio_driver virtio_net = { |
c45a6816 RR |
842 | .feature_table = features, |
843 | .feature_table_size = ARRAY_SIZE(features), | |
296f96fc RR |
844 | .driver.name = KBUILD_MODNAME, |
845 | .driver.owner = THIS_MODULE, | |
846 | .id_table = id_table, | |
847 | .probe = virtnet_probe, | |
848 | .remove = __devexit_p(virtnet_remove), | |
9f4d26d0 | 849 | .config_changed = virtnet_config_changed, |
296f96fc RR |
850 | }; |
851 | ||
852 | static int __init init(void) | |
853 | { | |
854 | return register_virtio_driver(&virtio_net); | |
855 | } | |
856 | ||
857 | static void __exit fini(void) | |
858 | { | |
859 | unregister_virtio_driver(&virtio_net); | |
860 | } | |
861 | module_init(init); | |
862 | module_exit(fini); | |
863 | ||
864 | MODULE_DEVICE_TABLE(virtio, id_table); | |
865 | MODULE_DESCRIPTION("Virtio network driver"); | |
866 | MODULE_LICENSE("GPL"); |