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Linux 4.1.16
[linux/fpc-iii.git] / drivers / net / virtio_net.c
blob237f8e5e493ddaae958684e8ed411c6f7f2363d6
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, see <http://www.gnu.org/licenses/>.
17 */
18 //#define DEBUG
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/ethtool.h>
22 #include <linux/module.h>
23 #include <linux/virtio.h>
24 #include <linux/virtio_net.h>
25 #include <linux/scatterlist.h>
26 #include <linux/if_vlan.h>
27 #include <linux/slab.h>
28 #include <linux/cpu.h>
29 #include <linux/average.h>
30 #include <net/busy_poll.h>
31
32 static int napi_weight = NAPI_POLL_WEIGHT;
33 module_param(napi_weight, int, 0444);
34
35 static bool csum = true, gso = true;
36 module_param(csum, bool, 0444);
37 module_param(gso, bool, 0444);
38
39 /* FIXME: MTU in config. */
40 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
41 #define GOOD_COPY_LEN 128
42
43 /* Weight used for the RX packet size EWMA. The average packet size is used to
44 * determine the packet buffer size when refilling RX rings. As the entire RX
45 * ring may be refilled at once, the weight is chosen so that the EWMA will be
46 * insensitive to short-term, transient changes in packet size.
47 */
48 #define RECEIVE_AVG_WEIGHT 64
49
50 /* Minimum alignment for mergeable packet buffers. */
51 #define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256)
52
53 #define VIRTNET_DRIVER_VERSION "1.0.0"
54
55 struct virtnet_stats {
56 struct u64_stats_sync tx_syncp;
57 struct u64_stats_sync rx_syncp;
58 u64 tx_bytes;
59 u64 tx_packets;
60
61 u64 rx_bytes;
62 u64 rx_packets;
63 };
64
65 /* Internal representation of a send virtqueue */
66 struct send_queue {
67 /* Virtqueue associated with this send _queue */
68 struct virtqueue *vq;
69
70 /* TX: fragments + linear part + virtio header */
71 struct scatterlist sg[MAX_SKB_FRAGS + 2];
72
73 /* Name of the send queue: output.$index */
74 char name[40];
75 };
76
77 /* Internal representation of a receive virtqueue */
78 struct receive_queue {
79 /* Virtqueue associated with this receive_queue */
80 struct virtqueue *vq;
81
82 struct napi_struct napi;
83
84 /* Chain pages by the private ptr. */
85 struct page *pages;
86
87 /* Average packet length for mergeable receive buffers. */
88 struct ewma mrg_avg_pkt_len;
89
90 /* Page frag for packet buffer allocation. */
91 struct page_frag alloc_frag;
92
93 /* RX: fragments + linear part + virtio header */
94 struct scatterlist sg[MAX_SKB_FRAGS + 2];
95
96 /* Name of this receive queue: input.$index */
97 char name[40];
98 };
99
100 struct virtnet_info {
101 struct virtio_device *vdev;
102 struct virtqueue *cvq;
103 struct net_device *dev;
104 struct send_queue *sq;
105 struct receive_queue *rq;
106 unsigned int status;
107
108 /* Max # of queue pairs supported by the device */
109 u16 max_queue_pairs;
110
111 /* # of queue pairs currently used by the driver */
112 u16 curr_queue_pairs;
113
114 /* I like... big packets and I cannot lie! */
115 bool big_packets;
116
117 /* Host will merge rx buffers for big packets (shake it! shake it!) */
118 bool mergeable_rx_bufs;
119
120 /* Has control virtqueue */
121 bool has_cvq;
122
123 /* Host can handle any s/g split between our header and packet data */
124 bool any_header_sg;
125
126 /* Packet virtio header size */
127 u8 hdr_len;
128
129 /* Active statistics */
130 struct virtnet_stats __percpu *stats;
131
132 /* Work struct for refilling if we run low on memory. */
133 struct delayed_work refill;
134
135 /* Work struct for config space updates */
136 struct work_struct config_work;
137
138 /* Does the affinity hint is set for virtqueues? */
139 bool affinity_hint_set;
140
141 /* CPU hot plug notifier */
142 struct notifier_block nb;
143 };
144
145 struct padded_vnet_hdr {
146 struct virtio_net_hdr_mrg_rxbuf hdr;
147 /*
148 * hdr is in a separate sg buffer, and data sg buffer shares same page
149 * with this header sg. This padding makes next sg 16 byte aligned
150 * after the header.
151 */
152 char padding[4];
153 };
154
155 /* Converting between virtqueue no. and kernel tx/rx queue no.
156 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
157 */
158 static int vq2txq(struct virtqueue *vq)
159 {
160 return (vq->index - 1) / 2;
161 }
162
163 static int txq2vq(int txq)
164 {
165 return txq * 2 + 1;
166 }
167
168 static int vq2rxq(struct virtqueue *vq)
169 {
170 return vq->index / 2;
171 }
172
173 static int rxq2vq(int rxq)
174 {
175 return rxq * 2;
176 }
177
178 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
179 {
180 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
181 }
182
183 /*
184 * private is used to chain pages for big packets, put the whole
185 * most recent used list in the beginning for reuse
186 */
187 static void give_pages(struct receive_queue *rq, struct page *page)
188 {
189 struct page *end;
190
191 /* Find end of list, sew whole thing into vi->rq.pages. */
192 for (end = page; end->private; end = (struct page *)end->private);
193 end->private = (unsigned long)rq->pages;
194 rq->pages = page;
195 }
196
197 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
198 {
199 struct page *p = rq->pages;
200
201 if (p) {
202 rq->pages = (struct page *)p->private;
203 /* clear private here, it is used to chain pages */
204 p->private = 0;
205 } else
206 p = alloc_page(gfp_mask);
207 return p;
208 }
209
210 static void skb_xmit_done(struct virtqueue *vq)
211 {
212 struct virtnet_info *vi = vq->vdev->priv;
213
214 /* Suppress further interrupts. */
215 virtqueue_disable_cb(vq);
216
217 /* We were probably waiting for more output buffers. */
218 netif_wake_subqueue(vi->dev, vq2txq(vq));
219 }
220
221 static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx)
222 {
223 unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1);
224 return (truesize + 1) * MERGEABLE_BUFFER_ALIGN;
225 }
226
227 static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx)
228 {
229 return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN);
230
231 }
232
233 static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize)
234 {
235 unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN;
236 return (unsigned long)buf | (size - 1);
237 }
238
239 /* Called from bottom half context */
240 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
241 struct receive_queue *rq,
242 struct page *page, unsigned int offset,
243 unsigned int len, unsigned int truesize)
244 {
245 struct sk_buff *skb;
246 struct virtio_net_hdr_mrg_rxbuf *hdr;
247 unsigned int copy, hdr_len, hdr_padded_len;
248 char *p;
249
250 p = page_address(page) + offset;
251
252 /* copy small packet so we can reuse these pages for small data */
253 skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
254 if (unlikely(!skb))
255 return NULL;
256
257 hdr = skb_vnet_hdr(skb);
258
259 hdr_len = vi->hdr_len;
260 if (vi->mergeable_rx_bufs)
261 hdr_padded_len = sizeof *hdr;
262 else
263 hdr_padded_len = sizeof(struct padded_vnet_hdr);
264
265 memcpy(hdr, p, hdr_len);
266
267 len -= hdr_len;
268 offset += hdr_padded_len;
269 p += hdr_padded_len;
270
271 copy = len;
272 if (copy > skb_tailroom(skb))
273 copy = skb_tailroom(skb);
274 memcpy(skb_put(skb, copy), p, copy);
275
276 len -= copy;
277 offset += copy;
278
279 if (vi->mergeable_rx_bufs) {
280 if (len)
281 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
282 else
283 put_page(page);
284 return skb;
285 }
286
287 /*
288 * Verify that we can indeed put this data into a skb.
289 * This is here to handle cases when the device erroneously
290 * tries to receive more than is possible. This is usually
291 * the case of a broken device.
292 */
293 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
294 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
295 dev_kfree_skb(skb);
296 return NULL;
297 }
298 BUG_ON(offset >= PAGE_SIZE);
299 while (len) {
300 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
301 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
302 frag_size, truesize);
303 len -= frag_size;
304 page = (struct page *)page->private;
305 offset = 0;
306 }
307
308 if (page)
309 give_pages(rq, page);
310
311 return skb;
312 }
313
314 static struct sk_buff *receive_small(struct virtnet_info *vi, void *buf, unsigned int len)
315 {
316 struct sk_buff * skb = buf;
317
318 len -= vi->hdr_len;
319 skb_trim(skb, len);
320
321 return skb;
322 }
323
324 static struct sk_buff *receive_big(struct net_device *dev,
325 struct virtnet_info *vi,
326 struct receive_queue *rq,
327 void *buf,
328 unsigned int len)
329 {
330 struct page *page = buf;
331 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
332
333 if (unlikely(!skb))
334 goto err;
335
336 return skb;
337
338 err:
339 dev->stats.rx_dropped++;
340 give_pages(rq, page);
341 return NULL;
342 }
343
344 static struct sk_buff *receive_mergeable(struct net_device *dev,
345 struct virtnet_info *vi,
346 struct receive_queue *rq,
347 unsigned long ctx,
348 unsigned int len)
349 {
350 void *buf = mergeable_ctx_to_buf_address(ctx);
351 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
352 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
353 struct page *page = virt_to_head_page(buf);
354 int offset = buf - page_address(page);
355 unsigned int truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
356
357 struct sk_buff *head_skb = page_to_skb(vi, rq, page, offset, len,
358 truesize);
359 struct sk_buff *curr_skb = head_skb;
360
361 if (unlikely(!curr_skb))
362 goto err_skb;
363 while (--num_buf) {
364 int num_skb_frags;
365
366 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
367 if (unlikely(!ctx)) {
368 pr_debug("%s: rx error: %d buffers out of %d missing\n",
369 dev->name, num_buf,
370 virtio16_to_cpu(vi->vdev,
371 hdr->num_buffers));
372 dev->stats.rx_length_errors++;
373 goto err_buf;
374 }
375
376 buf = mergeable_ctx_to_buf_address(ctx);
377 page = virt_to_head_page(buf);
378
379 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
380 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
381 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
382
383 if (unlikely(!nskb))
384 goto err_skb;
385 if (curr_skb == head_skb)
386 skb_shinfo(curr_skb)->frag_list = nskb;
387 else
388 curr_skb->next = nskb;
389 curr_skb = nskb;
390 head_skb->truesize += nskb->truesize;
391 num_skb_frags = 0;
392 }
393 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
394 if (curr_skb != head_skb) {
395 head_skb->data_len += len;
396 head_skb->len += len;
397 head_skb->truesize += truesize;
398 }
399 offset = buf - page_address(page);
400 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
401 put_page(page);
402 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
403 len, truesize);
404 } else {
405 skb_add_rx_frag(curr_skb, num_skb_frags, page,
406 offset, len, truesize);
407 }
408 }
409
410 ewma_add(&rq->mrg_avg_pkt_len, head_skb->len);
411 return head_skb;
412
413 err_skb:
414 put_page(page);
415 while (--num_buf) {
416 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
417 if (unlikely(!ctx)) {
418 pr_debug("%s: rx error: %d buffers missing\n",
419 dev->name, num_buf);
420 dev->stats.rx_length_errors++;
421 break;
422 }
423 page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx));
424 put_page(page);
425 }
426 err_buf:
427 dev->stats.rx_dropped++;
428 dev_kfree_skb(head_skb);
429 return NULL;
430 }
431
432 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
433 void *buf, unsigned int len)
434 {
435 struct net_device *dev = vi->dev;
436 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
437 struct sk_buff *skb;
438 struct virtio_net_hdr_mrg_rxbuf *hdr;
439
440 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
441 pr_debug("%s: short packet %i\n", dev->name, len);
442 dev->stats.rx_length_errors++;
443 if (vi->mergeable_rx_bufs) {
444 unsigned long ctx = (unsigned long)buf;
445 void *base = mergeable_ctx_to_buf_address(ctx);
446 put_page(virt_to_head_page(base));
447 } else if (vi->big_packets) {
448 give_pages(rq, buf);
449 } else {
450 dev_kfree_skb(buf);
451 }
452 return;
453 }
454
455 if (vi->mergeable_rx_bufs)
456 skb = receive_mergeable(dev, vi, rq, (unsigned long)buf, len);
457 else if (vi->big_packets)
458 skb = receive_big(dev, vi, rq, buf, len);
459 else
460 skb = receive_small(vi, buf, len);
461
462 if (unlikely(!skb))
463 return;
464
465 hdr = skb_vnet_hdr(skb);
466
467 u64_stats_update_begin(&stats->rx_syncp);
468 stats->rx_bytes += skb->len;
469 stats->rx_packets++;
470 u64_stats_update_end(&stats->rx_syncp);
471
472 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
473 pr_debug("Needs csum!\n");
474 if (!skb_partial_csum_set(skb,
475 virtio16_to_cpu(vi->vdev, hdr->hdr.csum_start),
476 virtio16_to_cpu(vi->vdev, hdr->hdr.csum_offset)))
477 goto frame_err;
478 } else if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID) {
479 skb->ip_summed = CHECKSUM_UNNECESSARY;
480 }
481
482 skb->protocol = eth_type_trans(skb, dev);
483 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
484 ntohs(skb->protocol), skb->len, skb->pkt_type);
485
486 if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
487 pr_debug("GSO!\n");
488 switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
489 case VIRTIO_NET_HDR_GSO_TCPV4:
490 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
491 break;
492 case VIRTIO_NET_HDR_GSO_UDP:
493 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
494 break;
495 case VIRTIO_NET_HDR_GSO_TCPV6:
496 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
497 break;
498 default:
499 net_warn_ratelimited("%s: bad gso type %u.\n",
500 dev->name, hdr->hdr.gso_type);
501 goto frame_err;
502 }
503
504 if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
505 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
506
507 skb_shinfo(skb)->gso_size = virtio16_to_cpu(vi->vdev,
508 hdr->hdr.gso_size);
509 if (skb_shinfo(skb)->gso_size == 0) {
510 net_warn_ratelimited("%s: zero gso size.\n", dev->name);
511 goto frame_err;
512 }
513
514 /* Header must be checked, and gso_segs computed. */
515 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
516 skb_shinfo(skb)->gso_segs = 0;
517 }
518
519 skb_mark_napi_id(skb, &rq->napi);
520
521 netif_receive_skb(skb);
522 return;
523
524 frame_err:
525 dev->stats.rx_frame_errors++;
526 dev_kfree_skb(skb);
527 }
528
529 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
530 gfp_t gfp)
531 {
532 struct sk_buff *skb;
533 struct virtio_net_hdr_mrg_rxbuf *hdr;
534 int err;
535
536 skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp);
537 if (unlikely(!skb))
538 return -ENOMEM;
539
540 skb_put(skb, GOOD_PACKET_LEN);
541
542 hdr = skb_vnet_hdr(skb);
543 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
544 sg_set_buf(rq->sg, hdr, vi->hdr_len);
545 skb_to_sgvec(skb, rq->sg + 1, 0, skb->len);
546
547 err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp);
548 if (err < 0)
549 dev_kfree_skb(skb);
550
551 return err;
552 }
553
554 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
555 gfp_t gfp)
556 {
557 struct page *first, *list = NULL;
558 char *p;
559 int i, err, offset;
560
561 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
562
563 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
564 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
565 first = get_a_page(rq, gfp);
566 if (!first) {
567 if (list)
568 give_pages(rq, list);
569 return -ENOMEM;
570 }
571 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
572
573 /* chain new page in list head to match sg */
574 first->private = (unsigned long)list;
575 list = first;
576 }
577
578 first = get_a_page(rq, gfp);
579 if (!first) {
580 give_pages(rq, list);
581 return -ENOMEM;
582 }
583 p = page_address(first);
584
585 /* rq->sg[0], rq->sg[1] share the same page */
586 /* a separated rq->sg[0] for header - required in case !any_header_sg */
587 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
588
589 /* rq->sg[1] for data packet, from offset */
590 offset = sizeof(struct padded_vnet_hdr);
591 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
592
593 /* chain first in list head */
594 first->private = (unsigned long)list;
595 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
596 first, gfp);
597 if (err < 0)
598 give_pages(rq, first);
599
600 return err;
601 }
602
603 static unsigned int get_mergeable_buf_len(struct ewma *avg_pkt_len)
604 {
605 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
606 unsigned int len;
607
608 len = hdr_len + clamp_t(unsigned int, ewma_read(avg_pkt_len),
609 GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
610 return ALIGN(len, MERGEABLE_BUFFER_ALIGN);
611 }
612
613 static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
614 {
615 struct page_frag *alloc_frag = &rq->alloc_frag;
616 char *buf;
617 unsigned long ctx;
618 int err;
619 unsigned int len, hole;
620
621 len = get_mergeable_buf_len(&rq->mrg_avg_pkt_len);
622 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
623 return -ENOMEM;
624
625 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
626 ctx = mergeable_buf_to_ctx(buf, len);
627 get_page(alloc_frag->page);
628 alloc_frag->offset += len;
629 hole = alloc_frag->size - alloc_frag->offset;
630 if (hole < len) {
631 /* To avoid internal fragmentation, if there is very likely not
632 * enough space for another buffer, add the remaining space to
633 * the current buffer. This extra space is not included in
634 * the truesize stored in ctx.
635 */
636 len += hole;
637 alloc_frag->offset += hole;
638 }
639
640 sg_init_one(rq->sg, buf, len);
641 err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, (void *)ctx, gfp);
642 if (err < 0)
643 put_page(virt_to_head_page(buf));
644
645 return err;
646 }
647
648 /*
649 * Returns false if we couldn't fill entirely (OOM).
650 *
651 * Normally run in the receive path, but can also be run from ndo_open
652 * before we're receiving packets, or from refill_work which is
653 * careful to disable receiving (using napi_disable).
654 */
655 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
656 gfp_t gfp)
657 {
658 int err;
659 bool oom;
660
661 gfp |= __GFP_COLD;
662 do {
663 if (vi->mergeable_rx_bufs)
664 err = add_recvbuf_mergeable(rq, gfp);
665 else if (vi->big_packets)
666 err = add_recvbuf_big(vi, rq, gfp);
667 else
668 err = add_recvbuf_small(vi, rq, gfp);
669
670 oom = err == -ENOMEM;
671 if (err)
672 break;
673 } while (rq->vq->num_free);
674 virtqueue_kick(rq->vq);
675 return !oom;
676 }
677
678 static void skb_recv_done(struct virtqueue *rvq)
679 {
680 struct virtnet_info *vi = rvq->vdev->priv;
681 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
682
683 /* Schedule NAPI, Suppress further interrupts if successful. */
684 if (napi_schedule_prep(&rq->napi)) {
685 virtqueue_disable_cb(rvq);
686 __napi_schedule(&rq->napi);
687 }
688 }
689
690 static void virtnet_napi_enable(struct receive_queue *rq)
691 {
692 napi_enable(&rq->napi);
693
694 /* If all buffers were filled by other side before we napi_enabled, we
695 * won't get another interrupt, so process any outstanding packets
696 * now. virtnet_poll wants re-enable the queue, so we disable here.
697 * We synchronize against interrupts via NAPI_STATE_SCHED */
698 if (napi_schedule_prep(&rq->napi)) {
699 virtqueue_disable_cb(rq->vq);
700 local_bh_disable();
701 __napi_schedule(&rq->napi);
702 local_bh_enable();
703 }
704 }
705
706 static void refill_work(struct work_struct *work)
707 {
708 struct virtnet_info *vi =
709 container_of(work, struct virtnet_info, refill.work);
710 bool still_empty;
711 int i;
712
713 for (i = 0; i < vi->curr_queue_pairs; i++) {
714 struct receive_queue *rq = &vi->rq[i];
715
716 napi_disable(&rq->napi);
717 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
718 virtnet_napi_enable(rq);
719
720 /* In theory, this can happen: if we don't get any buffers in
721 * we will *never* try to fill again.
722 */
723 if (still_empty)
724 schedule_delayed_work(&vi->refill, HZ/2);
725 }
726 }
727
728 static int virtnet_receive(struct receive_queue *rq, int budget)
729 {
730 struct virtnet_info *vi = rq->vq->vdev->priv;
731 unsigned int len, received = 0;
732 void *buf;
733
734 while (received < budget &&
735 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
736 receive_buf(vi, rq, buf, len);
737 received++;
738 }
739
740 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
741 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
742 schedule_delayed_work(&vi->refill, 0);
743 }
744
745 return received;
746 }
747
748 static int virtnet_poll(struct napi_struct *napi, int budget)
749 {
750 struct receive_queue *rq =
751 container_of(napi, struct receive_queue, napi);
752 unsigned int r, received;
753
754 received = virtnet_receive(rq, budget);
755
756 /* Out of packets? */
757 if (received < budget) {
758 r = virtqueue_enable_cb_prepare(rq->vq);
759 napi_complete(napi);
760 if (unlikely(virtqueue_poll(rq->vq, r)) &&
761 napi_schedule_prep(napi)) {
762 virtqueue_disable_cb(rq->vq);
763 __napi_schedule(napi);
764 }
765 }
766
767 return received;
768 }
769
770 #ifdef CONFIG_NET_RX_BUSY_POLL
771 /* must be called with local_bh_disable()d */
772 static int virtnet_busy_poll(struct napi_struct *napi)
773 {
774 struct receive_queue *rq =
775 container_of(napi, struct receive_queue, napi);
776 struct virtnet_info *vi = rq->vq->vdev->priv;
777 int r, received = 0, budget = 4;
778
779 if (!(vi->status & VIRTIO_NET_S_LINK_UP))
780 return LL_FLUSH_FAILED;
781
782 if (!napi_schedule_prep(napi))
783 return LL_FLUSH_BUSY;
784
785 virtqueue_disable_cb(rq->vq);
786
787 again:
788 received += virtnet_receive(rq, budget);
789
790 r = virtqueue_enable_cb_prepare(rq->vq);
791 clear_bit(NAPI_STATE_SCHED, &napi->state);
792 if (unlikely(virtqueue_poll(rq->vq, r)) &&
793 napi_schedule_prep(napi)) {
794 virtqueue_disable_cb(rq->vq);
795 if (received < budget) {
796 budget -= received;
797 goto again;
798 } else {
799 __napi_schedule(napi);
800 }
801 }
802
803 return received;
804 }
805 #endif /* CONFIG_NET_RX_BUSY_POLL */
806
807 static int virtnet_open(struct net_device *dev)
808 {
809 struct virtnet_info *vi = netdev_priv(dev);
810 int i;
811
812 for (i = 0; i < vi->max_queue_pairs; i++) {
813 if (i < vi->curr_queue_pairs)
814 /* Make sure we have some buffers: if oom use wq. */
815 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
816 schedule_delayed_work(&vi->refill, 0);
817 virtnet_napi_enable(&vi->rq[i]);
818 }
819
820 return 0;
821 }
822
823 static void free_old_xmit_skbs(struct send_queue *sq)
824 {
825 struct sk_buff *skb;
826 unsigned int len;
827 struct virtnet_info *vi = sq->vq->vdev->priv;
828 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
829
830 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
831 pr_debug("Sent skb %p\n", skb);
832
833 u64_stats_update_begin(&stats->tx_syncp);
834 stats->tx_bytes += skb->len;
835 stats->tx_packets++;
836 u64_stats_update_end(&stats->tx_syncp);
837
838 dev_kfree_skb_any(skb);
839 }
840 }
841
842 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
843 {
844 struct virtio_net_hdr_mrg_rxbuf *hdr;
845 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
846 struct virtnet_info *vi = sq->vq->vdev->priv;
847 unsigned num_sg;
848 unsigned hdr_len = vi->hdr_len;
849 bool can_push;
850
851 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
852
853 can_push = vi->any_header_sg &&
854 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
855 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
856 /* Even if we can, don't push here yet as this would skew
857 * csum_start offset below. */
858 if (can_push)
859 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
860 else
861 hdr = skb_vnet_hdr(skb);
862
863 if (skb->ip_summed == CHECKSUM_PARTIAL) {
864 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
865 hdr->hdr.csum_start = cpu_to_virtio16(vi->vdev,
866 skb_checksum_start_offset(skb));
867 hdr->hdr.csum_offset = cpu_to_virtio16(vi->vdev,
868 skb->csum_offset);
869 } else {
870 hdr->hdr.flags = 0;
871 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
872 }
873
874 if (skb_is_gso(skb)) {
875 hdr->hdr.hdr_len = cpu_to_virtio16(vi->vdev, skb_headlen(skb));
876 hdr->hdr.gso_size = cpu_to_virtio16(vi->vdev,
877 skb_shinfo(skb)->gso_size);
878 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
879 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
880 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
881 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
882 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
883 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
884 else
885 BUG();
886 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
887 hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
888 } else {
889 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
890 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
891 }
892
893 if (vi->mergeable_rx_bufs)
894 hdr->num_buffers = 0;
895
896 sg_init_table(sq->sg, MAX_SKB_FRAGS + 2);
897 if (can_push) {
898 __skb_push(skb, hdr_len);
899 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
900 /* Pull header back to avoid skew in tx bytes calculations. */
901 __skb_pull(skb, hdr_len);
902 } else {
903 sg_set_buf(sq->sg, hdr, hdr_len);
904 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
905 }
906 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
907 }
908
909 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
910 {
911 struct virtnet_info *vi = netdev_priv(dev);
912 int qnum = skb_get_queue_mapping(skb);
913 struct send_queue *sq = &vi->sq[qnum];
914 int err;
915 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
916 bool kick = !skb->xmit_more;
917
918 /* Free up any pending old buffers before queueing new ones. */
919 free_old_xmit_skbs(sq);
920
921 /* timestamp packet in software */
922 skb_tx_timestamp(skb);
923
924 /* Try to transmit */
925 err = xmit_skb(sq, skb);
926
927 /* This should not happen! */
928 if (unlikely(err)) {
929 dev->stats.tx_fifo_errors++;
930 if (net_ratelimit())
931 dev_warn(&dev->dev,
932 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
933 dev->stats.tx_dropped++;
934 dev_kfree_skb_any(skb);
935 return NETDEV_TX_OK;
936 }
937
938 /* Don't wait up for transmitted skbs to be freed. */
939 skb_orphan(skb);
940 nf_reset(skb);
941
942 /* If running out of space, stop queue to avoid getting packets that we
943 * are then unable to transmit.
944 * An alternative would be to force queuing layer to requeue the skb by
945 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
946 * returned in a normal path of operation: it means that driver is not
947 * maintaining the TX queue stop/start state properly, and causes
948 * the stack to do a non-trivial amount of useless work.
949 * Since most packets only take 1 or 2 ring slots, stopping the queue
950 * early means 16 slots are typically wasted.
951 */
952 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
953 netif_stop_subqueue(dev, qnum);
954 if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
955 /* More just got used, free them then recheck. */
956 free_old_xmit_skbs(sq);
957 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
958 netif_start_subqueue(dev, qnum);
959 virtqueue_disable_cb(sq->vq);
960 }
961 }
962 }
963
964 if (kick || netif_xmit_stopped(txq))
965 virtqueue_kick(sq->vq);
966
967 return NETDEV_TX_OK;
968 }
969
970 /*
971 * Send command via the control virtqueue and check status. Commands
972 * supported by the hypervisor, as indicated by feature bits, should
973 * never fail unless improperly formatted.
974 */
975 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
976 struct scatterlist *out)
977 {
978 struct scatterlist *sgs[4], hdr, stat;
979 struct virtio_net_ctrl_hdr ctrl;
980 virtio_net_ctrl_ack status = ~0;
981 unsigned out_num = 0, tmp;
982
983 /* Caller should know better */
984 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
985
986 ctrl.class = class;
987 ctrl.cmd = cmd;
988 /* Add header */
989 sg_init_one(&hdr, &ctrl, sizeof(ctrl));
990 sgs[out_num++] = &hdr;
991
992 if (out)
993 sgs[out_num++] = out;
994
995 /* Add return status. */
996 sg_init_one(&stat, &status, sizeof(status));
997 sgs[out_num] = &stat;
998
999 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1000 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1001
1002 if (unlikely(!virtqueue_kick(vi->cvq)))
1003 return status == VIRTIO_NET_OK;
1004
1005 /* Spin for a response, the kick causes an ioport write, trapping
1006 * into the hypervisor, so the request should be handled immediately.
1007 */
1008 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1009 !virtqueue_is_broken(vi->cvq))
1010 cpu_relax();
1011
1012 return status == VIRTIO_NET_OK;
1013 }
1014
1015 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1016 {
1017 struct virtnet_info *vi = netdev_priv(dev);
1018 struct virtio_device *vdev = vi->vdev;
1019 int ret;
1020 struct sockaddr *addr = p;
1021 struct scatterlist sg;
1022
1023 ret = eth_prepare_mac_addr_change(dev, p);
1024 if (ret)
1025 return ret;
1026
1027 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1028 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1029 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1030 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1031 dev_warn(&vdev->dev,
1032 "Failed to set mac address by vq command.\n");
1033 return -EINVAL;
1034 }
1035 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1036 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1037 unsigned int i;
1038
1039 /* Naturally, this has an atomicity problem. */
1040 for (i = 0; i < dev->addr_len; i++)
1041 virtio_cwrite8(vdev,
1042 offsetof(struct virtio_net_config, mac) +
1043 i, addr->sa_data[i]);
1044 }
1045
1046 eth_commit_mac_addr_change(dev, p);
1047
1048 return 0;
1049 }
1050
1051 static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,
1052 struct rtnl_link_stats64 *tot)
1053 {
1054 struct virtnet_info *vi = netdev_priv(dev);
1055 int cpu;
1056 unsigned int start;
1057
1058 for_each_possible_cpu(cpu) {
1059 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1060 u64 tpackets, tbytes, rpackets, rbytes;
1061
1062 do {
1063 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1064 tpackets = stats->tx_packets;
1065 tbytes = stats->tx_bytes;
1066 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1067
1068 do {
1069 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1070 rpackets = stats->rx_packets;
1071 rbytes = stats->rx_bytes;
1072 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1073
1074 tot->rx_packets += rpackets;
1075 tot->tx_packets += tpackets;
1076 tot->rx_bytes += rbytes;
1077 tot->tx_bytes += tbytes;
1078 }
1079
1080 tot->tx_dropped = dev->stats.tx_dropped;
1081 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1082 tot->rx_dropped = dev->stats.rx_dropped;
1083 tot->rx_length_errors = dev->stats.rx_length_errors;
1084 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1085
1086 return tot;
1087 }
1088
1089 #ifdef CONFIG_NET_POLL_CONTROLLER
1090 static void virtnet_netpoll(struct net_device *dev)
1091 {
1092 struct virtnet_info *vi = netdev_priv(dev);
1093 int i;
1094
1095 for (i = 0; i < vi->curr_queue_pairs; i++)
1096 napi_schedule(&vi->rq[i].napi);
1097 }
1098 #endif
1099
1100 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1101 {
1102 rtnl_lock();
1103 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1104 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1105 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1106 rtnl_unlock();
1107 }
1108
1109 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1110 {
1111 struct scatterlist sg;
1112 struct virtio_net_ctrl_mq s;
1113 struct net_device *dev = vi->dev;
1114
1115 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1116 return 0;
1117
1118 s.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1119 sg_init_one(&sg, &s, sizeof(s));
1120
1121 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1122 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1123 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1124 queue_pairs);
1125 return -EINVAL;
1126 } else {
1127 vi->curr_queue_pairs = queue_pairs;
1128 /* virtnet_open() will refill when device is going to up. */
1129 if (dev->flags & IFF_UP)
1130 schedule_delayed_work(&vi->refill, 0);
1131 }
1132
1133 return 0;
1134 }
1135
1136 static int virtnet_close(struct net_device *dev)
1137 {
1138 struct virtnet_info *vi = netdev_priv(dev);
1139 int i;
1140
1141 /* Make sure refill_work doesn't re-enable napi! */
1142 cancel_delayed_work_sync(&vi->refill);
1143
1144 for (i = 0; i < vi->max_queue_pairs; i++)
1145 napi_disable(&vi->rq[i].napi);
1146
1147 return 0;
1148 }
1149
1150 static void virtnet_set_rx_mode(struct net_device *dev)
1151 {
1152 struct virtnet_info *vi = netdev_priv(dev);
1153 struct scatterlist sg[2];
1154 u8 promisc, allmulti;
1155 struct virtio_net_ctrl_mac *mac_data;
1156 struct netdev_hw_addr *ha;
1157 int uc_count;
1158 int mc_count;
1159 void *buf;
1160 int i;
1161
1162 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1163 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1164 return;
1165
1166 promisc = ((dev->flags & IFF_PROMISC) != 0);
1167 allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1168
1169 sg_init_one(sg, &promisc, sizeof(promisc));
1170
1171 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1172 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1173 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1174 promisc ? "en" : "dis");
1175
1176 sg_init_one(sg, &allmulti, sizeof(allmulti));
1177
1178 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1179 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1180 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1181 allmulti ? "en" : "dis");
1182
1183 uc_count = netdev_uc_count(dev);
1184 mc_count = netdev_mc_count(dev);
1185 /* MAC filter - use one buffer for both lists */
1186 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1187 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1188 mac_data = buf;
1189 if (!buf)
1190 return;
1191
1192 sg_init_table(sg, 2);
1193
1194 /* Store the unicast list and count in the front of the buffer */
1195 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1196 i = 0;
1197 netdev_for_each_uc_addr(ha, dev)
1198 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1199
1200 sg_set_buf(&sg[0], mac_data,
1201 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1202
1203 /* multicast list and count fill the end */
1204 mac_data = (void *)&mac_data->macs[uc_count][0];
1205
1206 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1207 i = 0;
1208 netdev_for_each_mc_addr(ha, dev)
1209 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1210
1211 sg_set_buf(&sg[1], mac_data,
1212 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1213
1214 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1215 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1216 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1217
1218 kfree(buf);
1219 }
1220
1221 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1222 __be16 proto, u16 vid)
1223 {
1224 struct virtnet_info *vi = netdev_priv(dev);
1225 struct scatterlist sg;
1226
1227 sg_init_one(&sg, &vid, sizeof(vid));
1228
1229 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1230 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1231 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1232 return 0;
1233 }
1234
1235 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1236 __be16 proto, u16 vid)
1237 {
1238 struct virtnet_info *vi = netdev_priv(dev);
1239 struct scatterlist sg;
1240
1241 sg_init_one(&sg, &vid, sizeof(vid));
1242
1243 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1244 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1245 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1246 return 0;
1247 }
1248
1249 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1250 {
1251 int i;
1252
1253 if (vi->affinity_hint_set) {
1254 for (i = 0; i < vi->max_queue_pairs; i++) {
1255 virtqueue_set_affinity(vi->rq[i].vq, -1);
1256 virtqueue_set_affinity(vi->sq[i].vq, -1);
1257 }
1258
1259 vi->affinity_hint_set = false;
1260 }
1261 }
1262
1263 static void virtnet_set_affinity(struct virtnet_info *vi)
1264 {
1265 int i;
1266 int cpu;
1267
1268 /* In multiqueue mode, when the number of cpu is equal to the number of
1269 * queue pairs, we let the queue pairs to be private to one cpu by
1270 * setting the affinity hint to eliminate the contention.
1271 */
1272 if (vi->curr_queue_pairs == 1 ||
1273 vi->max_queue_pairs != num_online_cpus()) {
1274 virtnet_clean_affinity(vi, -1);
1275 return;
1276 }
1277
1278 i = 0;
1279 for_each_online_cpu(cpu) {
1280 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1281 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1282 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1283 i++;
1284 }
1285
1286 vi->affinity_hint_set = true;
1287 }
1288
1289 static int virtnet_cpu_callback(struct notifier_block *nfb,
1290 unsigned long action, void *hcpu)
1291 {
1292 struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb);
1293
1294 switch(action & ~CPU_TASKS_FROZEN) {
1295 case CPU_ONLINE:
1296 case CPU_DOWN_FAILED:
1297 case CPU_DEAD:
1298 virtnet_set_affinity(vi);
1299 break;
1300 case CPU_DOWN_PREPARE:
1301 virtnet_clean_affinity(vi, (long)hcpu);
1302 break;
1303 default:
1304 break;
1305 }
1306
1307 return NOTIFY_OK;
1308 }
1309
1310 static void virtnet_get_ringparam(struct net_device *dev,
1311 struct ethtool_ringparam *ring)
1312 {
1313 struct virtnet_info *vi = netdev_priv(dev);
1314
1315 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1316 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1317 ring->rx_pending = ring->rx_max_pending;
1318 ring->tx_pending = ring->tx_max_pending;
1319 }
1320
1321
1322 static void virtnet_get_drvinfo(struct net_device *dev,
1323 struct ethtool_drvinfo *info)
1324 {
1325 struct virtnet_info *vi = netdev_priv(dev);
1326 struct virtio_device *vdev = vi->vdev;
1327
1328 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1329 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1330 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1331
1332 }
1333
1334 /* TODO: Eliminate OOO packets during switching */
1335 static int virtnet_set_channels(struct net_device *dev,
1336 struct ethtool_channels *channels)
1337 {
1338 struct virtnet_info *vi = netdev_priv(dev);
1339 u16 queue_pairs = channels->combined_count;
1340 int err;
1341
1342 /* We don't support separate rx/tx channels.
1343 * We don't allow setting 'other' channels.
1344 */
1345 if (channels->rx_count || channels->tx_count || channels->other_count)
1346 return -EINVAL;
1347
1348 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1349 return -EINVAL;
1350
1351 get_online_cpus();
1352 err = virtnet_set_queues(vi, queue_pairs);
1353 if (!err) {
1354 netif_set_real_num_tx_queues(dev, queue_pairs);
1355 netif_set_real_num_rx_queues(dev, queue_pairs);
1356
1357 virtnet_set_affinity(vi);
1358 }
1359 put_online_cpus();
1360
1361 return err;
1362 }
1363
1364 static void virtnet_get_channels(struct net_device *dev,
1365 struct ethtool_channels *channels)
1366 {
1367 struct virtnet_info *vi = netdev_priv(dev);
1368
1369 channels->combined_count = vi->curr_queue_pairs;
1370 channels->max_combined = vi->max_queue_pairs;
1371 channels->max_other = 0;
1372 channels->rx_count = 0;
1373 channels->tx_count = 0;
1374 channels->other_count = 0;
1375 }
1376
1377 static const struct ethtool_ops virtnet_ethtool_ops = {
1378 .get_drvinfo = virtnet_get_drvinfo,
1379 .get_link = ethtool_op_get_link,
1380 .get_ringparam = virtnet_get_ringparam,
1381 .set_channels = virtnet_set_channels,
1382 .get_channels = virtnet_get_channels,
1383 .get_ts_info = ethtool_op_get_ts_info,
1384 };
1385
1386 #define MIN_MTU 68
1387 #define MAX_MTU 65535
1388
1389 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
1390 {
1391 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
1392 return -EINVAL;
1393 dev->mtu = new_mtu;
1394 return 0;
1395 }
1396
1397 static const struct net_device_ops virtnet_netdev = {
1398 .ndo_open = virtnet_open,
1399 .ndo_stop = virtnet_close,
1400 .ndo_start_xmit = start_xmit,
1401 .ndo_validate_addr = eth_validate_addr,
1402 .ndo_set_mac_address = virtnet_set_mac_address,
1403 .ndo_set_rx_mode = virtnet_set_rx_mode,
1404 .ndo_change_mtu = virtnet_change_mtu,
1405 .ndo_get_stats64 = virtnet_stats,
1406 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
1407 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
1408 #ifdef CONFIG_NET_POLL_CONTROLLER
1409 .ndo_poll_controller = virtnet_netpoll,
1410 #endif
1411 #ifdef CONFIG_NET_RX_BUSY_POLL
1412 .ndo_busy_poll = virtnet_busy_poll,
1413 #endif
1414 };
1415
1416 static void virtnet_config_changed_work(struct work_struct *work)
1417 {
1418 struct virtnet_info *vi =
1419 container_of(work, struct virtnet_info, config_work);
1420 u16 v;
1421
1422 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
1423 struct virtio_net_config, status, &v) < 0)
1424 return;
1425
1426 if (v & VIRTIO_NET_S_ANNOUNCE) {
1427 netdev_notify_peers(vi->dev);
1428 virtnet_ack_link_announce(vi);
1429 }
1430
1431 /* Ignore unknown (future) status bits */
1432 v &= VIRTIO_NET_S_LINK_UP;
1433
1434 if (vi->status == v)
1435 return;
1436
1437 vi->status = v;
1438
1439 if (vi->status & VIRTIO_NET_S_LINK_UP) {
1440 netif_carrier_on(vi->dev);
1441 netif_tx_wake_all_queues(vi->dev);
1442 } else {
1443 netif_carrier_off(vi->dev);
1444 netif_tx_stop_all_queues(vi->dev);
1445 }
1446 }
1447
1448 static void virtnet_config_changed(struct virtio_device *vdev)
1449 {
1450 struct virtnet_info *vi = vdev->priv;
1451
1452 schedule_work(&vi->config_work);
1453 }
1454
1455 static void virtnet_free_queues(struct virtnet_info *vi)
1456 {
1457 int i;
1458
1459 for (i = 0; i < vi->max_queue_pairs; i++) {
1460 napi_hash_del(&vi->rq[i].napi);
1461 netif_napi_del(&vi->rq[i].napi);
1462 }
1463
1464 kfree(vi->rq);
1465 kfree(vi->sq);
1466 }
1467
1468 static void free_receive_bufs(struct virtnet_info *vi)
1469 {
1470 int i;
1471
1472 for (i = 0; i < vi->max_queue_pairs; i++) {
1473 while (vi->rq[i].pages)
1474 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
1475 }
1476 }
1477
1478 static void free_receive_page_frags(struct virtnet_info *vi)
1479 {
1480 int i;
1481 for (i = 0; i < vi->max_queue_pairs; i++)
1482 if (vi->rq[i].alloc_frag.page)
1483 put_page(vi->rq[i].alloc_frag.page);
1484 }
1485
1486 static void free_unused_bufs(struct virtnet_info *vi)
1487 {
1488 void *buf;
1489 int i;
1490
1491 for (i = 0; i < vi->max_queue_pairs; i++) {
1492 struct virtqueue *vq = vi->sq[i].vq;
1493 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
1494 dev_kfree_skb(buf);
1495 }
1496
1497 for (i = 0; i < vi->max_queue_pairs; i++) {
1498 struct virtqueue *vq = vi->rq[i].vq;
1499
1500 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
1501 if (vi->mergeable_rx_bufs) {
1502 unsigned long ctx = (unsigned long)buf;
1503 void *base = mergeable_ctx_to_buf_address(ctx);
1504 put_page(virt_to_head_page(base));
1505 } else if (vi->big_packets) {
1506 give_pages(&vi->rq[i], buf);
1507 } else {
1508 dev_kfree_skb(buf);
1509 }
1510 }
1511 }
1512 }
1513
1514 static void virtnet_del_vqs(struct virtnet_info *vi)
1515 {
1516 struct virtio_device *vdev = vi->vdev;
1517
1518 virtnet_clean_affinity(vi, -1);
1519
1520 vdev->config->del_vqs(vdev);
1521
1522 virtnet_free_queues(vi);
1523 }
1524
1525 static int virtnet_find_vqs(struct virtnet_info *vi)
1526 {
1527 vq_callback_t **callbacks;
1528 struct virtqueue **vqs;
1529 int ret = -ENOMEM;
1530 int i, total_vqs;
1531 const char **names;
1532
1533 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
1534 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
1535 * possible control vq.
1536 */
1537 total_vqs = vi->max_queue_pairs * 2 +
1538 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
1539
1540 /* Allocate space for find_vqs parameters */
1541 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
1542 if (!vqs)
1543 goto err_vq;
1544 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
1545 if (!callbacks)
1546 goto err_callback;
1547 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
1548 if (!names)
1549 goto err_names;
1550
1551 /* Parameters for control virtqueue, if any */
1552 if (vi->has_cvq) {
1553 callbacks[total_vqs - 1] = NULL;
1554 names[total_vqs - 1] = "control";
1555 }
1556
1557 /* Allocate/initialize parameters for send/receive virtqueues */
1558 for (i = 0; i < vi->max_queue_pairs; i++) {
1559 callbacks[rxq2vq(i)] = skb_recv_done;
1560 callbacks[txq2vq(i)] = skb_xmit_done;
1561 sprintf(vi->rq[i].name, "input.%d", i);
1562 sprintf(vi->sq[i].name, "output.%d", i);
1563 names[rxq2vq(i)] = vi->rq[i].name;
1564 names[txq2vq(i)] = vi->sq[i].name;
1565 }
1566
1567 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
1568 names);
1569 if (ret)
1570 goto err_find;
1571
1572 if (vi->has_cvq) {
1573 vi->cvq = vqs[total_vqs - 1];
1574 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
1575 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1576 }
1577
1578 for (i = 0; i < vi->max_queue_pairs; i++) {
1579 vi->rq[i].vq = vqs[rxq2vq(i)];
1580 vi->sq[i].vq = vqs[txq2vq(i)];
1581 }
1582
1583 kfree(names);
1584 kfree(callbacks);
1585 kfree(vqs);
1586
1587 return 0;
1588
1589 err_find:
1590 kfree(names);
1591 err_names:
1592 kfree(callbacks);
1593 err_callback:
1594 kfree(vqs);
1595 err_vq:
1596 return ret;
1597 }
1598
1599 static int virtnet_alloc_queues(struct virtnet_info *vi)
1600 {
1601 int i;
1602
1603 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
1604 if (!vi->sq)
1605 goto err_sq;
1606 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
1607 if (!vi->rq)
1608 goto err_rq;
1609
1610 INIT_DELAYED_WORK(&vi->refill, refill_work);
1611 for (i = 0; i < vi->max_queue_pairs; i++) {
1612 vi->rq[i].pages = NULL;
1613 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
1614 napi_weight);
1615 napi_hash_add(&vi->rq[i].napi);
1616
1617 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
1618 ewma_init(&vi->rq[i].mrg_avg_pkt_len, 1, RECEIVE_AVG_WEIGHT);
1619 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
1620 }
1621
1622 return 0;
1623
1624 err_rq:
1625 kfree(vi->sq);
1626 err_sq:
1627 return -ENOMEM;
1628 }
1629
1630 static int init_vqs(struct virtnet_info *vi)
1631 {
1632 int ret;
1633
1634 /* Allocate send & receive queues */
1635 ret = virtnet_alloc_queues(vi);
1636 if (ret)
1637 goto err;
1638
1639 ret = virtnet_find_vqs(vi);
1640 if (ret)
1641 goto err_free;
1642
1643 get_online_cpus();
1644 virtnet_set_affinity(vi);
1645 put_online_cpus();
1646
1647 return 0;
1648
1649 err_free:
1650 virtnet_free_queues(vi);
1651 err:
1652 return ret;
1653 }
1654
1655 #ifdef CONFIG_SYSFS
1656 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
1657 struct rx_queue_attribute *attribute, char *buf)
1658 {
1659 struct virtnet_info *vi = netdev_priv(queue->dev);
1660 unsigned int queue_index = get_netdev_rx_queue_index(queue);
1661 struct ewma *avg;
1662
1663 BUG_ON(queue_index >= vi->max_queue_pairs);
1664 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
1665 return sprintf(buf, "%u\n", get_mergeable_buf_len(avg));
1666 }
1667
1668 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
1669 __ATTR_RO(mergeable_rx_buffer_size);
1670
1671 static struct attribute *virtio_net_mrg_rx_attrs[] = {
1672 &mergeable_rx_buffer_size_attribute.attr,
1673 NULL
1674 };
1675
1676 static const struct attribute_group virtio_net_mrg_rx_group = {
1677 .name = "virtio_net",
1678 .attrs = virtio_net_mrg_rx_attrs
1679 };
1680 #endif
1681
1682 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
1683 unsigned int fbit,
1684 const char *fname, const char *dname)
1685 {
1686 if (!virtio_has_feature(vdev, fbit))
1687 return false;
1688
1689 dev_err(&vdev->dev, "device advertises feature %s but not %s",
1690 fname, dname);
1691
1692 return true;
1693 }
1694
1695 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
1696 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
1697
1698 static bool virtnet_validate_features(struct virtio_device *vdev)
1699 {
1700 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
1701 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
1702 "VIRTIO_NET_F_CTRL_VQ") ||
1703 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
1704 "VIRTIO_NET_F_CTRL_VQ") ||
1705 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
1706 "VIRTIO_NET_F_CTRL_VQ") ||
1707 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
1708 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
1709 "VIRTIO_NET_F_CTRL_VQ"))) {
1710 return false;
1711 }
1712
1713 return true;
1714 }
1715
1716 static int virtnet_probe(struct virtio_device *vdev)
1717 {
1718 int i, err;
1719 struct net_device *dev;
1720 struct virtnet_info *vi;
1721 u16 max_queue_pairs;
1722
1723 if (!vdev->config->get) {
1724 dev_err(&vdev->dev, "%s failure: config access disabled\n",
1725 __func__);
1726 return -EINVAL;
1727 }
1728
1729 if (!virtnet_validate_features(vdev))
1730 return -EINVAL;
1731
1732 /* Find if host supports multiqueue virtio_net device */
1733 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
1734 struct virtio_net_config,
1735 max_virtqueue_pairs, &max_queue_pairs);
1736
1737 /* We need at least 2 queue's */
1738 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
1739 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
1740 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
1741 max_queue_pairs = 1;
1742
1743 /* Allocate ourselves a network device with room for our info */
1744 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
1745 if (!dev)
1746 return -ENOMEM;
1747
1748 /* Set up network device as normal. */
1749 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
1750 dev->netdev_ops = &virtnet_netdev;
1751 dev->features = NETIF_F_HIGHDMA;
1752
1753 dev->ethtool_ops = &virtnet_ethtool_ops;
1754 SET_NETDEV_DEV(dev, &vdev->dev);
1755
1756 /* Do we support "hardware" checksums? */
1757 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
1758 /* This opens up the world of extra features. */
1759 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
1760 if (csum)
1761 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
1762
1763 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
1764 dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
1765 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
1766 }
1767 /* Individual feature bits: what can host handle? */
1768 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
1769 dev->hw_features |= NETIF_F_TSO;
1770 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
1771 dev->hw_features |= NETIF_F_TSO6;
1772 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
1773 dev->hw_features |= NETIF_F_TSO_ECN;
1774 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
1775 dev->hw_features |= NETIF_F_UFO;
1776
1777 dev->features |= NETIF_F_GSO_ROBUST;
1778
1779 if (gso)
1780 dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
1781 /* (!csum && gso) case will be fixed by register_netdev() */
1782 }
1783 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
1784 dev->features |= NETIF_F_RXCSUM;
1785
1786 dev->vlan_features = dev->features;
1787
1788 /* Configuration may specify what MAC to use. Otherwise random. */
1789 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
1790 virtio_cread_bytes(vdev,
1791 offsetof(struct virtio_net_config, mac),
1792 dev->dev_addr, dev->addr_len);
1793 else
1794 eth_hw_addr_random(dev);
1795
1796 /* Set up our device-specific information */
1797 vi = netdev_priv(dev);
1798 vi->dev = dev;
1799 vi->vdev = vdev;
1800 vdev->priv = vi;
1801 vi->stats = alloc_percpu(struct virtnet_stats);
1802 err = -ENOMEM;
1803 if (vi->stats == NULL)
1804 goto free;
1805
1806 for_each_possible_cpu(i) {
1807 struct virtnet_stats *virtnet_stats;
1808 virtnet_stats = per_cpu_ptr(vi->stats, i);
1809 u64_stats_init(&virtnet_stats->tx_syncp);
1810 u64_stats_init(&virtnet_stats->rx_syncp);
1811 }
1812
1813 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
1814
1815 /* If we can receive ANY GSO packets, we must allocate large ones. */
1816 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1817 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1818 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
1819 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
1820 vi->big_packets = true;
1821
1822 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
1823 vi->mergeable_rx_bufs = true;
1824
1825 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
1826 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
1827 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
1828 else
1829 vi->hdr_len = sizeof(struct virtio_net_hdr);
1830
1831 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
1832 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
1833 vi->any_header_sg = true;
1834
1835 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
1836 vi->has_cvq = true;
1837
1838 if (vi->any_header_sg)
1839 dev->needed_headroom = vi->hdr_len;
1840
1841 /* Use single tx/rx queue pair as default */
1842 vi->curr_queue_pairs = 1;
1843 vi->max_queue_pairs = max_queue_pairs;
1844
1845 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
1846 err = init_vqs(vi);
1847 if (err)
1848 goto free_stats;
1849
1850 #ifdef CONFIG_SYSFS
1851 if (vi->mergeable_rx_bufs)
1852 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
1853 #endif
1854 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
1855 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
1856
1857 err = register_netdev(dev);
1858 if (err) {
1859 pr_debug("virtio_net: registering device failed\n");
1860 goto free_vqs;
1861 }
1862
1863 virtio_device_ready(vdev);
1864
1865 /* Last of all, set up some receive buffers. */
1866 for (i = 0; i < vi->curr_queue_pairs; i++) {
1867 try_fill_recv(vi, &vi->rq[i], GFP_KERNEL);
1868
1869 /* If we didn't even get one input buffer, we're useless. */
1870 if (vi->rq[i].vq->num_free ==
1871 virtqueue_get_vring_size(vi->rq[i].vq)) {
1872 free_unused_bufs(vi);
1873 err = -ENOMEM;
1874 goto free_recv_bufs;
1875 }
1876 }
1877
1878 vi->nb.notifier_call = &virtnet_cpu_callback;
1879 err = register_hotcpu_notifier(&vi->nb);
1880 if (err) {
1881 pr_debug("virtio_net: registering cpu notifier failed\n");
1882 goto free_recv_bufs;
1883 }
1884
1885 /* Assume link up if device can't report link status,
1886 otherwise get link status from config. */
1887 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
1888 netif_carrier_off(dev);
1889 schedule_work(&vi->config_work);
1890 } else {
1891 vi->status = VIRTIO_NET_S_LINK_UP;
1892 netif_carrier_on(dev);
1893 }
1894
1895 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
1896 dev->name, max_queue_pairs);
1897
1898 return 0;
1899
1900 free_recv_bufs:
1901 vi->vdev->config->reset(vdev);
1902
1903 free_receive_bufs(vi);
1904 unregister_netdev(dev);
1905 free_vqs:
1906 cancel_delayed_work_sync(&vi->refill);
1907 free_receive_page_frags(vi);
1908 virtnet_del_vqs(vi);
1909 free_stats:
1910 free_percpu(vi->stats);
1911 free:
1912 free_netdev(dev);
1913 return err;
1914 }
1915
1916 static void remove_vq_common(struct virtnet_info *vi)
1917 {
1918 vi->vdev->config->reset(vi->vdev);
1919
1920 /* Free unused buffers in both send and recv, if any. */
1921 free_unused_bufs(vi);
1922
1923 free_receive_bufs(vi);
1924
1925 free_receive_page_frags(vi);
1926
1927 virtnet_del_vqs(vi);
1928 }
1929
1930 static void virtnet_remove(struct virtio_device *vdev)
1931 {
1932 struct virtnet_info *vi = vdev->priv;
1933
1934 unregister_hotcpu_notifier(&vi->nb);
1935
1936 /* Make sure no work handler is accessing the device. */
1937 flush_work(&vi->config_work);
1938
1939 unregister_netdev(vi->dev);
1940
1941 remove_vq_common(vi);
1942
1943 free_percpu(vi->stats);
1944 free_netdev(vi->dev);
1945 }
1946
1947 #ifdef CONFIG_PM_SLEEP
1948 static int virtnet_freeze(struct virtio_device *vdev)
1949 {
1950 struct virtnet_info *vi = vdev->priv;
1951 int i;
1952
1953 unregister_hotcpu_notifier(&vi->nb);
1954
1955 /* Make sure no work handler is accessing the device */
1956 flush_work(&vi->config_work);
1957
1958 netif_device_detach(vi->dev);
1959 cancel_delayed_work_sync(&vi->refill);
1960
1961 if (netif_running(vi->dev)) {
1962 for (i = 0; i < vi->max_queue_pairs; i++)
1963 napi_disable(&vi->rq[i].napi);
1964 }
1965
1966 remove_vq_common(vi);
1967
1968 return 0;
1969 }
1970
1971 static int virtnet_restore(struct virtio_device *vdev)
1972 {
1973 struct virtnet_info *vi = vdev->priv;
1974 int err, i;
1975
1976 err = init_vqs(vi);
1977 if (err)
1978 return err;
1979
1980 virtio_device_ready(vdev);
1981
1982 if (netif_running(vi->dev)) {
1983 for (i = 0; i < vi->curr_queue_pairs; i++)
1984 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1985 schedule_delayed_work(&vi->refill, 0);
1986
1987 for (i = 0; i < vi->max_queue_pairs; i++)
1988 virtnet_napi_enable(&vi->rq[i]);
1989 }
1990
1991 netif_device_attach(vi->dev);
1992
1993 rtnl_lock();
1994 virtnet_set_queues(vi, vi->curr_queue_pairs);
1995 rtnl_unlock();
1996
1997 err = register_hotcpu_notifier(&vi->nb);
1998 if (err)
1999 return err;
2000
2001 return 0;
2002 }
2003 #endif
2004
2005 static struct virtio_device_id id_table[] = {
2006 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
2007 { 0 },
2008 };
2009
2010 static unsigned int features[] = {
2011 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
2012 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
2013 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
2014 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
2015 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
2016 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
2017 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
2018 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ,
2019 VIRTIO_NET_F_CTRL_MAC_ADDR,
2020 VIRTIO_F_ANY_LAYOUT,
2021 };
2022
2023 static struct virtio_driver virtio_net_driver = {
2024 .feature_table = features,
2025 .feature_table_size = ARRAY_SIZE(features),
2026 .driver.name = KBUILD_MODNAME,
2027 .driver.owner = THIS_MODULE,
2028 .id_table = id_table,
2029 .probe = virtnet_probe,
2030 .remove = virtnet_remove,
2031 .config_changed = virtnet_config_changed,
2032 #ifdef CONFIG_PM_SLEEP
2033 .freeze = virtnet_freeze,
2034 .restore = virtnet_restore,
2035 #endif
2036 };
2037
2038 module_virtio_driver(virtio_net_driver);
2039
2040 MODULE_DEVICE_TABLE(virtio, id_table);
2041 MODULE_DESCRIPTION("Virtio network driver");
2042 MODULE_LICENSE("GPL");
Linux with added FPC-III support