sfc: Create multiple TX queues
[linux/fpc-iii.git] / drivers / net / virtio_net.c
blobb0a85d0387962b6ce2394637f9ae6dbbac5f6684
1 /* A network driver using virtio.
3 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
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.
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.
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
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 #include <linux/slab.h>
30 static int napi_weight = 128;
31 module_param(napi_weight, int, 0444);
33 static int csum = 1, gso = 1;
34 module_param(csum, bool, 0444);
35 module_param(gso, bool, 0444);
37 /* FIXME: MTU in config. */
38 #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
39 #define GOOD_COPY_LEN 128
41 #define VIRTNET_SEND_COMMAND_SG_MAX 2
43 struct virtnet_info {
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;
50 /* Number of input buffers, and max we've ever had. */
51 unsigned int num, max;
53 /* I like... big packets and I cannot lie! */
54 bool big_packets;
56 /* Host will merge rx buffers for big packets (shake it! shake it!) */
57 bool mergeable_rx_bufs;
59 /* Work struct for refilling if we run low on memory. */
60 struct delayed_work refill;
62 /* Chain pages by the private ptr. */
63 struct page *pages;
65 /* fragments + linear part + virtio header */
66 struct scatterlist rx_sg[MAX_SKB_FRAGS + 2];
67 struct scatterlist tx_sg[MAX_SKB_FRAGS + 2];
70 struct skb_vnet_hdr {
71 union {
72 struct virtio_net_hdr hdr;
73 struct virtio_net_hdr_mrg_rxbuf mhdr;
75 unsigned int num_sg;
78 struct padded_vnet_hdr {
79 struct virtio_net_hdr hdr;
81 * virtio_net_hdr should be in a separated sg buffer because of a
82 * QEMU bug, and data sg buffer shares same page with this header sg.
83 * This padding makes next sg 16 byte aligned after virtio_net_hdr.
85 char padding[6];
88 static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
90 return (struct skb_vnet_hdr *)skb->cb;
94 * private is used to chain pages for big packets, put the whole
95 * most recent used list in the beginning for reuse
97 static void give_pages(struct virtnet_info *vi, struct page *page)
99 struct page *end;
101 /* Find end of list, sew whole thing into vi->pages. */
102 for (end = page; end->private; end = (struct page *)end->private);
103 end->private = (unsigned long)vi->pages;
104 vi->pages = page;
107 static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
109 struct page *p = vi->pages;
111 if (p) {
112 vi->pages = (struct page *)p->private;
113 /* clear private here, it is used to chain pages */
114 p->private = 0;
115 } else
116 p = alloc_page(gfp_mask);
117 return p;
120 static void skb_xmit_done(struct virtqueue *svq)
122 struct virtnet_info *vi = svq->vdev->priv;
124 /* Suppress further interrupts. */
125 svq->vq_ops->disable_cb(svq);
127 /* We were probably waiting for more output buffers. */
128 netif_wake_queue(vi->dev);
131 static void set_skb_frag(struct sk_buff *skb, struct page *page,
132 unsigned int offset, unsigned int *len)
134 int i = skb_shinfo(skb)->nr_frags;
135 skb_frag_t *f;
137 f = &skb_shinfo(skb)->frags[i];
138 f->size = min((unsigned)PAGE_SIZE - offset, *len);
139 f->page_offset = offset;
140 f->page = page;
142 skb->data_len += f->size;
143 skb->len += f->size;
144 skb_shinfo(skb)->nr_frags++;
145 *len -= f->size;
148 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
149 struct page *page, unsigned int len)
151 struct sk_buff *skb;
152 struct skb_vnet_hdr *hdr;
153 unsigned int copy, hdr_len, offset;
154 char *p;
156 p = page_address(page);
158 /* copy small packet so we can reuse these pages for small data */
159 skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
160 if (unlikely(!skb))
161 return NULL;
163 hdr = skb_vnet_hdr(skb);
165 if (vi->mergeable_rx_bufs) {
166 hdr_len = sizeof hdr->mhdr;
167 offset = hdr_len;
168 } else {
169 hdr_len = sizeof hdr->hdr;
170 offset = sizeof(struct padded_vnet_hdr);
173 memcpy(hdr, p, hdr_len);
175 len -= hdr_len;
176 p += offset;
178 copy = len;
179 if (copy > skb_tailroom(skb))
180 copy = skb_tailroom(skb);
181 memcpy(skb_put(skb, copy), p, copy);
183 len -= copy;
184 offset += copy;
186 while (len) {
187 set_skb_frag(skb, page, offset, &len);
188 page = (struct page *)page->private;
189 offset = 0;
192 if (page)
193 give_pages(vi, page);
195 return skb;
198 static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb)
200 struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
201 struct page *page;
202 int num_buf, i, len;
204 num_buf = hdr->mhdr.num_buffers;
205 while (--num_buf) {
206 i = skb_shinfo(skb)->nr_frags;
207 if (i >= MAX_SKB_FRAGS) {
208 pr_debug("%s: packet too long\n", skb->dev->name);
209 skb->dev->stats.rx_length_errors++;
210 return -EINVAL;
213 page = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
214 if (!page) {
215 pr_debug("%s: rx error: %d buffers missing\n",
216 skb->dev->name, hdr->mhdr.num_buffers);
217 skb->dev->stats.rx_length_errors++;
218 return -EINVAL;
220 if (len > PAGE_SIZE)
221 len = PAGE_SIZE;
223 set_skb_frag(skb, page, 0, &len);
225 --vi->num;
227 return 0;
230 static void receive_buf(struct net_device *dev, void *buf, unsigned int len)
232 struct virtnet_info *vi = netdev_priv(dev);
233 struct sk_buff *skb;
234 struct page *page;
235 struct skb_vnet_hdr *hdr;
237 if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
238 pr_debug("%s: short packet %i\n", dev->name, len);
239 dev->stats.rx_length_errors++;
240 if (vi->mergeable_rx_bufs || vi->big_packets)
241 give_pages(vi, buf);
242 else
243 dev_kfree_skb(buf);
244 return;
247 if (!vi->mergeable_rx_bufs && !vi->big_packets) {
248 skb = buf;
249 len -= sizeof(struct virtio_net_hdr);
250 skb_trim(skb, len);
251 } else {
252 page = buf;
253 skb = page_to_skb(vi, page, len);
254 if (unlikely(!skb)) {
255 dev->stats.rx_dropped++;
256 give_pages(vi, page);
257 return;
259 if (vi->mergeable_rx_bufs)
260 if (receive_mergeable(vi, skb)) {
261 dev_kfree_skb(skb);
262 return;
266 hdr = skb_vnet_hdr(skb);
267 skb->truesize += skb->data_len;
268 dev->stats.rx_bytes += skb->len;
269 dev->stats.rx_packets++;
271 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
272 pr_debug("Needs csum!\n");
273 if (!skb_partial_csum_set(skb,
274 hdr->hdr.csum_start,
275 hdr->hdr.csum_offset))
276 goto frame_err;
279 skb->protocol = eth_type_trans(skb, dev);
280 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
281 ntohs(skb->protocol), skb->len, skb->pkt_type);
283 if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
284 pr_debug("GSO!\n");
285 switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
286 case VIRTIO_NET_HDR_GSO_TCPV4:
287 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
288 break;
289 case VIRTIO_NET_HDR_GSO_UDP:
290 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
291 break;
292 case VIRTIO_NET_HDR_GSO_TCPV6:
293 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
294 break;
295 default:
296 if (net_ratelimit())
297 printk(KERN_WARNING "%s: bad gso type %u.\n",
298 dev->name, hdr->hdr.gso_type);
299 goto frame_err;
302 if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
303 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
305 skb_shinfo(skb)->gso_size = hdr->hdr.gso_size;
306 if (skb_shinfo(skb)->gso_size == 0) {
307 if (net_ratelimit())
308 printk(KERN_WARNING "%s: zero gso size.\n",
309 dev->name);
310 goto frame_err;
313 /* Header must be checked, and gso_segs computed. */
314 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
315 skb_shinfo(skb)->gso_segs = 0;
318 netif_receive_skb(skb);
319 return;
321 frame_err:
322 dev->stats.rx_frame_errors++;
323 dev_kfree_skb(skb);
326 static int add_recvbuf_small(struct virtnet_info *vi, gfp_t gfp)
328 struct sk_buff *skb;
329 struct skb_vnet_hdr *hdr;
330 int err;
332 skb = netdev_alloc_skb_ip_align(vi->dev, MAX_PACKET_LEN);
333 if (unlikely(!skb))
334 return -ENOMEM;
336 skb_put(skb, MAX_PACKET_LEN);
338 hdr = skb_vnet_hdr(skb);
339 sg_set_buf(vi->rx_sg, &hdr->hdr, sizeof hdr->hdr);
341 skb_to_sgvec(skb, vi->rx_sg + 1, 0, skb->len);
343 err = vi->rvq->vq_ops->add_buf(vi->rvq, vi->rx_sg, 0, 2, skb);
344 if (err < 0)
345 dev_kfree_skb(skb);
347 return err;
350 static int add_recvbuf_big(struct virtnet_info *vi, gfp_t gfp)
352 struct page *first, *list = NULL;
353 char *p;
354 int i, err, offset;
356 /* page in vi->rx_sg[MAX_SKB_FRAGS + 1] is list tail */
357 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
358 first = get_a_page(vi, gfp);
359 if (!first) {
360 if (list)
361 give_pages(vi, list);
362 return -ENOMEM;
364 sg_set_buf(&vi->rx_sg[i], page_address(first), PAGE_SIZE);
366 /* chain new page in list head to match sg */
367 first->private = (unsigned long)list;
368 list = first;
371 first = get_a_page(vi, gfp);
372 if (!first) {
373 give_pages(vi, list);
374 return -ENOMEM;
376 p = page_address(first);
378 /* vi->rx_sg[0], vi->rx_sg[1] share the same page */
379 /* a separated vi->rx_sg[0] for virtio_net_hdr only due to QEMU bug */
380 sg_set_buf(&vi->rx_sg[0], p, sizeof(struct virtio_net_hdr));
382 /* vi->rx_sg[1] for data packet, from offset */
383 offset = sizeof(struct padded_vnet_hdr);
384 sg_set_buf(&vi->rx_sg[1], p + offset, PAGE_SIZE - offset);
386 /* chain first in list head */
387 first->private = (unsigned long)list;
388 err = vi->rvq->vq_ops->add_buf(vi->rvq, vi->rx_sg, 0, MAX_SKB_FRAGS + 2,
389 first);
390 if (err < 0)
391 give_pages(vi, first);
393 return err;
396 static int add_recvbuf_mergeable(struct virtnet_info *vi, gfp_t gfp)
398 struct page *page;
399 int err;
401 page = get_a_page(vi, gfp);
402 if (!page)
403 return -ENOMEM;
405 sg_init_one(vi->rx_sg, page_address(page), PAGE_SIZE);
407 err = vi->rvq->vq_ops->add_buf(vi->rvq, vi->rx_sg, 0, 1, page);
408 if (err < 0)
409 give_pages(vi, page);
411 return err;
414 /* Returns false if we couldn't fill entirely (OOM). */
415 static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
417 int err;
418 bool oom = false;
420 do {
421 if (vi->mergeable_rx_bufs)
422 err = add_recvbuf_mergeable(vi, gfp);
423 else if (vi->big_packets)
424 err = add_recvbuf_big(vi, gfp);
425 else
426 err = add_recvbuf_small(vi, gfp);
428 if (err < 0) {
429 oom = true;
430 break;
432 ++vi->num;
433 } while (err > 0);
434 if (unlikely(vi->num > vi->max))
435 vi->max = vi->num;
436 vi->rvq->vq_ops->kick(vi->rvq);
437 return !oom;
440 static void skb_recv_done(struct virtqueue *rvq)
442 struct virtnet_info *vi = rvq->vdev->priv;
443 /* Schedule NAPI, Suppress further interrupts if successful. */
444 if (napi_schedule_prep(&vi->napi)) {
445 rvq->vq_ops->disable_cb(rvq);
446 __napi_schedule(&vi->napi);
450 static void refill_work(struct work_struct *work)
452 struct virtnet_info *vi;
453 bool still_empty;
455 vi = container_of(work, struct virtnet_info, refill.work);
456 napi_disable(&vi->napi);
457 still_empty = !try_fill_recv(vi, GFP_KERNEL);
458 napi_enable(&vi->napi);
460 /* In theory, this can happen: if we don't get any buffers in
461 * we will *never* try to fill again. */
462 if (still_empty)
463 schedule_delayed_work(&vi->refill, HZ/2);
466 static int virtnet_poll(struct napi_struct *napi, int budget)
468 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
469 void *buf;
470 unsigned int len, received = 0;
472 again:
473 while (received < budget &&
474 (buf = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
475 receive_buf(vi->dev, buf, len);
476 --vi->num;
477 received++;
480 if (vi->num < vi->max / 2) {
481 if (!try_fill_recv(vi, GFP_ATOMIC))
482 schedule_delayed_work(&vi->refill, 0);
485 /* Out of packets? */
486 if (received < budget) {
487 napi_complete(napi);
488 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) &&
489 napi_schedule_prep(napi)) {
490 vi->rvq->vq_ops->disable_cb(vi->rvq);
491 __napi_schedule(napi);
492 goto again;
496 return received;
499 static unsigned int free_old_xmit_skbs(struct virtnet_info *vi)
501 struct sk_buff *skb;
502 unsigned int len, tot_sgs = 0;
504 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
505 pr_debug("Sent skb %p\n", skb);
506 vi->dev->stats.tx_bytes += skb->len;
507 vi->dev->stats.tx_packets++;
508 tot_sgs += skb_vnet_hdr(skb)->num_sg;
509 dev_kfree_skb_any(skb);
511 return tot_sgs;
514 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
516 struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
517 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
519 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
521 if (skb->ip_summed == CHECKSUM_PARTIAL) {
522 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
523 hdr->hdr.csum_start = skb->csum_start - skb_headroom(skb);
524 hdr->hdr.csum_offset = skb->csum_offset;
525 } else {
526 hdr->hdr.flags = 0;
527 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
530 if (skb_is_gso(skb)) {
531 hdr->hdr.hdr_len = skb_headlen(skb);
532 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
533 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
534 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
535 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
536 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
537 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
538 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
539 else
540 BUG();
541 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
542 hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
543 } else {
544 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
545 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
548 hdr->mhdr.num_buffers = 0;
550 /* Encode metadata header at front. */
551 if (vi->mergeable_rx_bufs)
552 sg_set_buf(vi->tx_sg, &hdr->mhdr, sizeof hdr->mhdr);
553 else
554 sg_set_buf(vi->tx_sg, &hdr->hdr, sizeof hdr->hdr);
556 hdr->num_sg = skb_to_sgvec(skb, vi->tx_sg + 1, 0, skb->len) + 1;
557 return vi->svq->vq_ops->add_buf(vi->svq, vi->tx_sg, hdr->num_sg,
558 0, skb);
561 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
563 struct virtnet_info *vi = netdev_priv(dev);
564 int capacity;
566 again:
567 /* Free up any pending old buffers before queueing new ones. */
568 free_old_xmit_skbs(vi);
570 /* Try to transmit */
571 capacity = xmit_skb(vi, skb);
573 /* This can happen with OOM and indirect buffers. */
574 if (unlikely(capacity < 0)) {
575 netif_stop_queue(dev);
576 dev_warn(&dev->dev, "Unexpected full queue\n");
577 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
578 vi->svq->vq_ops->disable_cb(vi->svq);
579 netif_start_queue(dev);
580 goto again;
582 return NETDEV_TX_BUSY;
584 vi->svq->vq_ops->kick(vi->svq);
586 /* Don't wait up for transmitted skbs to be freed. */
587 skb_orphan(skb);
588 nf_reset(skb);
590 /* Apparently nice girls don't return TX_BUSY; stop the queue
591 * before it gets out of hand. Naturally, this wastes entries. */
592 if (capacity < 2+MAX_SKB_FRAGS) {
593 netif_stop_queue(dev);
594 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
595 /* More just got used, free them then recheck. */
596 capacity += free_old_xmit_skbs(vi);
597 if (capacity >= 2+MAX_SKB_FRAGS) {
598 netif_start_queue(dev);
599 vi->svq->vq_ops->disable_cb(vi->svq);
604 return NETDEV_TX_OK;
607 static int virtnet_set_mac_address(struct net_device *dev, void *p)
609 struct virtnet_info *vi = netdev_priv(dev);
610 struct virtio_device *vdev = vi->vdev;
611 int ret;
613 ret = eth_mac_addr(dev, p);
614 if (ret)
615 return ret;
617 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
618 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
619 dev->dev_addr, dev->addr_len);
621 return 0;
624 #ifdef CONFIG_NET_POLL_CONTROLLER
625 static void virtnet_netpoll(struct net_device *dev)
627 struct virtnet_info *vi = netdev_priv(dev);
629 napi_schedule(&vi->napi);
631 #endif
633 static int virtnet_open(struct net_device *dev)
635 struct virtnet_info *vi = netdev_priv(dev);
637 napi_enable(&vi->napi);
639 /* If all buffers were filled by other side before we napi_enabled, we
640 * won't get another interrupt, so process any outstanding packets
641 * now. virtnet_poll wants re-enable the queue, so we disable here.
642 * We synchronize against interrupts via NAPI_STATE_SCHED */
643 if (napi_schedule_prep(&vi->napi)) {
644 vi->rvq->vq_ops->disable_cb(vi->rvq);
645 __napi_schedule(&vi->napi);
647 return 0;
651 * Send command via the control virtqueue and check status. Commands
652 * supported by the hypervisor, as indicated by feature bits, should
653 * never fail unless improperly formated.
655 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
656 struct scatterlist *data, int out, int in)
658 struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
659 struct virtio_net_ctrl_hdr ctrl;
660 virtio_net_ctrl_ack status = ~0;
661 unsigned int tmp;
662 int i;
664 /* Caller should know better */
665 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
666 (out + in > VIRTNET_SEND_COMMAND_SG_MAX));
668 out++; /* Add header */
669 in++; /* Add return status */
671 ctrl.class = class;
672 ctrl.cmd = cmd;
674 sg_init_table(sg, out + in);
676 sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
677 for_each_sg(data, s, out + in - 2, i)
678 sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
679 sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
681 BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) < 0);
683 vi->cvq->vq_ops->kick(vi->cvq);
686 * Spin for a response, the kick causes an ioport write, trapping
687 * into the hypervisor, so the request should be handled immediately.
689 while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp))
690 cpu_relax();
692 return status == VIRTIO_NET_OK;
695 static int virtnet_close(struct net_device *dev)
697 struct virtnet_info *vi = netdev_priv(dev);
699 napi_disable(&vi->napi);
701 return 0;
704 static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
706 struct virtnet_info *vi = netdev_priv(dev);
707 struct virtio_device *vdev = vi->vdev;
709 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
710 return -ENOSYS;
712 return ethtool_op_set_tx_hw_csum(dev, data);
715 static void virtnet_set_rx_mode(struct net_device *dev)
717 struct virtnet_info *vi = netdev_priv(dev);
718 struct scatterlist sg[2];
719 u8 promisc, allmulti;
720 struct virtio_net_ctrl_mac *mac_data;
721 struct netdev_hw_addr *ha;
722 int uc_count;
723 int mc_count;
724 void *buf;
725 int i;
727 /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
728 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
729 return;
731 promisc = ((dev->flags & IFF_PROMISC) != 0);
732 allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
734 sg_init_one(sg, &promisc, sizeof(promisc));
736 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
737 VIRTIO_NET_CTRL_RX_PROMISC,
738 sg, 1, 0))
739 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
740 promisc ? "en" : "dis");
742 sg_init_one(sg, &allmulti, sizeof(allmulti));
744 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
745 VIRTIO_NET_CTRL_RX_ALLMULTI,
746 sg, 1, 0))
747 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
748 allmulti ? "en" : "dis");
750 uc_count = netdev_uc_count(dev);
751 mc_count = netdev_mc_count(dev);
752 /* MAC filter - use one buffer for both lists */
753 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
754 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
755 mac_data = buf;
756 if (!buf) {
757 dev_warn(&dev->dev, "No memory for MAC address buffer\n");
758 return;
761 sg_init_table(sg, 2);
763 /* Store the unicast list and count in the front of the buffer */
764 mac_data->entries = uc_count;
765 i = 0;
766 netdev_for_each_uc_addr(ha, dev)
767 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
769 sg_set_buf(&sg[0], mac_data,
770 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
772 /* multicast list and count fill the end */
773 mac_data = (void *)&mac_data->macs[uc_count][0];
775 mac_data->entries = mc_count;
776 i = 0;
777 netdev_for_each_mc_addr(ha, dev)
778 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
780 sg_set_buf(&sg[1], mac_data,
781 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
783 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
784 VIRTIO_NET_CTRL_MAC_TABLE_SET,
785 sg, 2, 0))
786 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
788 kfree(buf);
791 static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
793 struct virtnet_info *vi = netdev_priv(dev);
794 struct scatterlist sg;
796 sg_init_one(&sg, &vid, sizeof(vid));
798 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
799 VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
800 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
803 static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
805 struct virtnet_info *vi = netdev_priv(dev);
806 struct scatterlist sg;
808 sg_init_one(&sg, &vid, sizeof(vid));
810 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
811 VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
812 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
815 static const struct ethtool_ops virtnet_ethtool_ops = {
816 .set_tx_csum = virtnet_set_tx_csum,
817 .set_sg = ethtool_op_set_sg,
818 .set_tso = ethtool_op_set_tso,
819 .set_ufo = ethtool_op_set_ufo,
820 .get_link = ethtool_op_get_link,
823 #define MIN_MTU 68
824 #define MAX_MTU 65535
826 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
828 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
829 return -EINVAL;
830 dev->mtu = new_mtu;
831 return 0;
834 static const struct net_device_ops virtnet_netdev = {
835 .ndo_open = virtnet_open,
836 .ndo_stop = virtnet_close,
837 .ndo_start_xmit = start_xmit,
838 .ndo_validate_addr = eth_validate_addr,
839 .ndo_set_mac_address = virtnet_set_mac_address,
840 .ndo_set_rx_mode = virtnet_set_rx_mode,
841 .ndo_change_mtu = virtnet_change_mtu,
842 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
843 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
844 #ifdef CONFIG_NET_POLL_CONTROLLER
845 .ndo_poll_controller = virtnet_netpoll,
846 #endif
849 static void virtnet_update_status(struct virtnet_info *vi)
851 u16 v;
853 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS))
854 return;
856 vi->vdev->config->get(vi->vdev,
857 offsetof(struct virtio_net_config, status),
858 &v, sizeof(v));
860 /* Ignore unknown (future) status bits */
861 v &= VIRTIO_NET_S_LINK_UP;
863 if (vi->status == v)
864 return;
866 vi->status = v;
868 if (vi->status & VIRTIO_NET_S_LINK_UP) {
869 netif_carrier_on(vi->dev);
870 netif_wake_queue(vi->dev);
871 } else {
872 netif_carrier_off(vi->dev);
873 netif_stop_queue(vi->dev);
877 static void virtnet_config_changed(struct virtio_device *vdev)
879 struct virtnet_info *vi = vdev->priv;
881 virtnet_update_status(vi);
884 static int virtnet_probe(struct virtio_device *vdev)
886 int err;
887 struct net_device *dev;
888 struct virtnet_info *vi;
889 struct virtqueue *vqs[3];
890 vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
891 const char *names[] = { "input", "output", "control" };
892 int nvqs;
894 /* Allocate ourselves a network device with room for our info */
895 dev = alloc_etherdev(sizeof(struct virtnet_info));
896 if (!dev)
897 return -ENOMEM;
899 /* Set up network device as normal. */
900 dev->netdev_ops = &virtnet_netdev;
901 dev->features = NETIF_F_HIGHDMA;
902 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
903 SET_NETDEV_DEV(dev, &vdev->dev);
905 /* Do we support "hardware" checksums? */
906 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
907 /* This opens up the world of extra features. */
908 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
909 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
910 dev->features |= NETIF_F_TSO | NETIF_F_UFO
911 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
913 /* Individual feature bits: what can host handle? */
914 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
915 dev->features |= NETIF_F_TSO;
916 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
917 dev->features |= NETIF_F_TSO6;
918 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
919 dev->features |= NETIF_F_TSO_ECN;
920 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
921 dev->features |= NETIF_F_UFO;
924 /* Configuration may specify what MAC to use. Otherwise random. */
925 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
926 vdev->config->get(vdev,
927 offsetof(struct virtio_net_config, mac),
928 dev->dev_addr, dev->addr_len);
929 } else
930 random_ether_addr(dev->dev_addr);
932 /* Set up our device-specific information */
933 vi = netdev_priv(dev);
934 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
935 vi->dev = dev;
936 vi->vdev = vdev;
937 vdev->priv = vi;
938 vi->pages = NULL;
939 INIT_DELAYED_WORK(&vi->refill, refill_work);
940 sg_init_table(vi->rx_sg, ARRAY_SIZE(vi->rx_sg));
941 sg_init_table(vi->tx_sg, ARRAY_SIZE(vi->tx_sg));
943 /* If we can receive ANY GSO packets, we must allocate large ones. */
944 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
945 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
946 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
947 vi->big_packets = true;
949 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
950 vi->mergeable_rx_bufs = true;
952 /* We expect two virtqueues, receive then send,
953 * and optionally control. */
954 nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
956 err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);
957 if (err)
958 goto free;
960 vi->rvq = vqs[0];
961 vi->svq = vqs[1];
963 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
964 vi->cvq = vqs[2];
966 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
967 dev->features |= NETIF_F_HW_VLAN_FILTER;
970 err = register_netdev(dev);
971 if (err) {
972 pr_debug("virtio_net: registering device failed\n");
973 goto free_vqs;
976 /* Last of all, set up some receive buffers. */
977 try_fill_recv(vi, GFP_KERNEL);
979 /* If we didn't even get one input buffer, we're useless. */
980 if (vi->num == 0) {
981 err = -ENOMEM;
982 goto unregister;
985 vi->status = VIRTIO_NET_S_LINK_UP;
986 virtnet_update_status(vi);
987 netif_carrier_on(dev);
989 pr_debug("virtnet: registered device %s\n", dev->name);
990 return 0;
992 unregister:
993 unregister_netdev(dev);
994 cancel_delayed_work_sync(&vi->refill);
995 free_vqs:
996 vdev->config->del_vqs(vdev);
997 free:
998 free_netdev(dev);
999 return err;
1002 static void free_unused_bufs(struct virtnet_info *vi)
1004 void *buf;
1005 while (1) {
1006 buf = vi->svq->vq_ops->detach_unused_buf(vi->svq);
1007 if (!buf)
1008 break;
1009 dev_kfree_skb(buf);
1011 while (1) {
1012 buf = vi->rvq->vq_ops->detach_unused_buf(vi->rvq);
1013 if (!buf)
1014 break;
1015 if (vi->mergeable_rx_bufs || vi->big_packets)
1016 give_pages(vi, buf);
1017 else
1018 dev_kfree_skb(buf);
1019 --vi->num;
1021 BUG_ON(vi->num != 0);
1024 static void __devexit virtnet_remove(struct virtio_device *vdev)
1026 struct virtnet_info *vi = vdev->priv;
1028 /* Stop all the virtqueues. */
1029 vdev->config->reset(vdev);
1032 unregister_netdev(vi->dev);
1033 cancel_delayed_work_sync(&vi->refill);
1035 /* Free unused buffers in both send and recv, if any. */
1036 free_unused_bufs(vi);
1038 vdev->config->del_vqs(vi->vdev);
1040 while (vi->pages)
1041 __free_pages(get_a_page(vi, GFP_KERNEL), 0);
1043 free_netdev(vi->dev);
1046 static struct virtio_device_id id_table[] = {
1047 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
1048 { 0 },
1051 static unsigned int features[] = {
1052 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
1053 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
1054 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
1055 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
1056 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
1057 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
1058 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
1061 static struct virtio_driver virtio_net_driver = {
1062 .feature_table = features,
1063 .feature_table_size = ARRAY_SIZE(features),
1064 .driver.name = KBUILD_MODNAME,
1065 .driver.owner = THIS_MODULE,
1066 .id_table = id_table,
1067 .probe = virtnet_probe,
1068 .remove = __devexit_p(virtnet_remove),
1069 .config_changed = virtnet_config_changed,
1072 static int __init init(void)
1074 return register_virtio_driver(&virtio_net_driver);
1077 static void __exit fini(void)
1079 unregister_virtio_driver(&virtio_net_driver);
1081 module_init(init);
1082 module_exit(fini);
1084 MODULE_DEVICE_TABLE(virtio, id_table);
1085 MODULE_DESCRIPTION("Virtio network driver");
1086 MODULE_LICENSE("GPL");