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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
31static int napi_weight = NAPI_POLL_WEIGHT;
32module_param(napi_weight, int, 0444);
33
34static bool csum = true, gso = true;
35module_param(csum, bool, 0444);
36module_param(gso, bool, 0444);
37
38/* FIXME: MTU in config. */
39#define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
40#define GOOD_COPY_LEN 128
41
42/* Weight used for the RX packet size EWMA. The average packet size is used to
43 * determine the packet buffer size when refilling RX rings. As the entire RX
44 * ring may be refilled at once, the weight is chosen so that the EWMA will be
45 * insensitive to short-term, transient changes in packet size.
46 */
47#define RECEIVE_AVG_WEIGHT 64
48
49/* Minimum alignment for mergeable packet buffers. */
50#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256)
51
52#define VIRTNET_DRIVER_VERSION "1.0.0"
53
54struct virtnet_stats {
55 struct u64_stats_sync tx_syncp;
56 struct u64_stats_sync rx_syncp;
57 u64 tx_bytes;
58 u64 tx_packets;
59
60 u64 rx_bytes;
61 u64 rx_packets;
62};
63
64/* Internal representation of a send virtqueue */
65struct send_queue {
66 /* Virtqueue associated with this send _queue */
67 struct virtqueue *vq;
68
69 /* TX: fragments + linear part + virtio header */
70 struct scatterlist sg[MAX_SKB_FRAGS + 2];
71
72 /* Name of the send queue: output.$index */
73 char name[40];
74};
75
76/* Internal representation of a receive virtqueue */
77struct receive_queue {
78 /* Virtqueue associated with this receive_queue */
79 struct virtqueue *vq;
80
81 struct napi_struct napi;
82
83 /* Chain pages by the private ptr. */
84 struct page *pages;
85
86 /* Average packet length for mergeable receive buffers. */
87 struct ewma mrg_avg_pkt_len;
88
89 /* Page frag for packet buffer allocation. */
90 struct page_frag alloc_frag;
91
92 /* RX: fragments + linear part + virtio header */
93 struct scatterlist sg[MAX_SKB_FRAGS + 2];
94
95 /* Name of this receive queue: input.$index */
96 char name[40];
97};
98
99struct virtnet_info {
100 struct virtio_device *vdev;
101 struct virtqueue *cvq;
102 struct net_device *dev;
103 struct send_queue *sq;
104 struct receive_queue *rq;
105 unsigned int status;
106
107 /* Max # of queue pairs supported by the device */
108 u16 max_queue_pairs;
109
110 /* # of queue pairs currently used by the driver */
111 u16 curr_queue_pairs;
112
113 /* I like... big packets and I cannot lie! */
114 bool big_packets;
115
116 /* Host will merge rx buffers for big packets (shake it! shake it!) */
117 bool mergeable_rx_bufs;
118
119 /* Has control virtqueue */
120 bool has_cvq;
121
122 /* Host can handle any s/g split between our header and packet data */
123 bool any_header_sg;
124
125 /* enable config space updates */
126 bool config_enable;
127
128 /* Active statistics */
129 struct virtnet_stats __percpu *stats;
130
131 /* Work struct for refilling if we run low on memory. */
132 struct delayed_work refill;
133
134 /* Work struct for config space updates */
135 struct work_struct config_work;
136
137 /* Lock for config space updates */
138 struct mutex config_lock;
139
140 /* Does the affinity hint is set for virtqueues? */
141 bool affinity_hint_set;
142
143 /* CPU hot plug notifier */
144 struct notifier_block nb;
145};
146
147struct skb_vnet_hdr {
148 union {
149 struct virtio_net_hdr hdr;
150 struct virtio_net_hdr_mrg_rxbuf mhdr;
151 };
152};
153
154struct padded_vnet_hdr {
155 struct virtio_net_hdr hdr;
156 /*
157 * virtio_net_hdr should be in a separated sg buffer because of a
158 * QEMU bug, and data sg buffer shares same page with this header sg.
159 * This padding makes next sg 16 byte aligned after virtio_net_hdr.
160 */
161 char padding[6];
162};
163
164/* Converting between virtqueue no. and kernel tx/rx queue no.
165 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
166 */
167static int vq2txq(struct virtqueue *vq)
168{
169 return (vq->index - 1) / 2;
170}
171
172static int txq2vq(int txq)
173{
174 return txq * 2 + 1;
175}
176
177static int vq2rxq(struct virtqueue *vq)
178{
179 return vq->index / 2;
180}
181
182static int rxq2vq(int rxq)
183{
184 return rxq * 2;
185}
186
187static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
188{
189 return (struct skb_vnet_hdr *)skb->cb;
190}
191
192/*
193 * private is used to chain pages for big packets, put the whole
194 * most recent used list in the beginning for reuse
195 */
196static void give_pages(struct receive_queue *rq, struct page *page)
197{
198 struct page *end;
199
200 /* Find end of list, sew whole thing into vi->rq.pages. */
201 for (end = page; end->private; end = (struct page *)end->private);
202 end->private = (unsigned long)rq->pages;
203 rq->pages = page;
204}
205
206static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
207{
208 struct page *p = rq->pages;
209
210 if (p) {
211 rq->pages = (struct page *)p->private;
212 /* clear private here, it is used to chain pages */
213 p->private = 0;
214 } else
215 p = alloc_page(gfp_mask);
216 return p;
217}
218
219static void skb_xmit_done(struct virtqueue *vq)
220{
221 struct virtnet_info *vi = vq->vdev->priv;
222
223 /* Suppress further interrupts. */
224 virtqueue_disable_cb(vq);
225
226 /* We were probably waiting for more output buffers. */
227 netif_wake_subqueue(vi->dev, vq2txq(vq));
228}
229
230static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx)
231{
232 unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1);
233 return (truesize + 1) * MERGEABLE_BUFFER_ALIGN;
234}
235
236static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx)
237{
238 return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN);
239
240}
241
242static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize)
243{
244 unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN;
245 return (unsigned long)buf | (size - 1);
246}
247
248/* Called from bottom half context */
249static struct sk_buff *page_to_skb(struct receive_queue *rq,
250 struct page *page, unsigned int offset,
251 unsigned int len, unsigned int truesize)
252{
253 struct virtnet_info *vi = rq->vq->vdev->priv;
254 struct sk_buff *skb;
255 struct skb_vnet_hdr *hdr;
256 unsigned int copy, hdr_len, hdr_padded_len;
257 char *p;
258
259 p = page_address(page) + offset;
260
261 /* copy small packet so we can reuse these pages for small data */
262 skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
263 if (unlikely(!skb))
264 return NULL;
265
266 hdr = skb_vnet_hdr(skb);
267
268 if (vi->mergeable_rx_bufs) {
269 hdr_len = sizeof hdr->mhdr;
270 hdr_padded_len = sizeof hdr->mhdr;
271 } else {
272 hdr_len = sizeof hdr->hdr;
273 hdr_padded_len = sizeof(struct padded_vnet_hdr);
274 }
275
276 memcpy(hdr, p, hdr_len);
277
278 len -= hdr_len;
279 offset += hdr_padded_len;
280 p += hdr_padded_len;
281
282 copy = len;
283 if (copy > skb_tailroom(skb))
284 copy = skb_tailroom(skb);
285 memcpy(skb_put(skb, copy), p, copy);
286
287 len -= copy;
288 offset += copy;
289
290 if (vi->mergeable_rx_bufs) {
291 if (len)
292 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
293 else
294 put_page(page);
295 return skb;
296 }
297
298 /*
299 * Verify that we can indeed put this data into a skb.
300 * This is here to handle cases when the device erroneously
301 * tries to receive more than is possible. This is usually
302 * the case of a broken device.
303 */
304 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
305 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
306 dev_kfree_skb(skb);
307 return NULL;
308 }
309 BUG_ON(offset >= PAGE_SIZE);
310 while (len) {
311 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
312 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
313 frag_size, truesize);
314 len -= frag_size;
315 page = (struct page *)page->private;
316 offset = 0;
317 }
318
319 if (page)
320 give_pages(rq, page);
321
322 return skb;
323}
324
325static struct sk_buff *receive_small(void *buf, unsigned int len)
326{
327 struct sk_buff * skb = buf;
328
329 len -= sizeof(struct virtio_net_hdr);
330 skb_trim(skb, len);
331
332 return skb;
333}
334
335static struct sk_buff *receive_big(struct net_device *dev,
336 struct receive_queue *rq,
337 void *buf,
338 unsigned int len)
339{
340 struct page *page = buf;
341 struct sk_buff *skb = page_to_skb(rq, page, 0, len, PAGE_SIZE);
342
343 if (unlikely(!skb))
344 goto err;
345
346 return skb;
347
348err:
349 dev->stats.rx_dropped++;
350 give_pages(rq, page);
351 return NULL;
352}
353
354static struct sk_buff *receive_mergeable(struct net_device *dev,
355 struct receive_queue *rq,
356 unsigned long ctx,
357 unsigned int len)
358{
359 void *buf = mergeable_ctx_to_buf_address(ctx);
360 struct skb_vnet_hdr *hdr = buf;
361 int num_buf = hdr->mhdr.num_buffers;
362 struct page *page = virt_to_head_page(buf);
363 int offset = buf - page_address(page);
364 unsigned int truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
365
366 struct sk_buff *head_skb = page_to_skb(rq, page, offset, len, truesize);
367 struct sk_buff *curr_skb = head_skb;
368
369 if (unlikely(!curr_skb))
370 goto err_skb;
371 while (--num_buf) {
372 int num_skb_frags;
373
374 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
375 if (unlikely(!ctx)) {
376 pr_debug("%s: rx error: %d buffers out of %d missing\n",
377 dev->name, num_buf, hdr->mhdr.num_buffers);
378 dev->stats.rx_length_errors++;
379 goto err_buf;
380 }
381
382 buf = mergeable_ctx_to_buf_address(ctx);
383 page = virt_to_head_page(buf);
384
385 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
386 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
387 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
388
389 if (unlikely(!nskb))
390 goto err_skb;
391 if (curr_skb == head_skb)
392 skb_shinfo(curr_skb)->frag_list = nskb;
393 else
394 curr_skb->next = nskb;
395 curr_skb = nskb;
396 head_skb->truesize += nskb->truesize;
397 num_skb_frags = 0;
398 }
399 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
400 if (curr_skb != head_skb) {
401 head_skb->data_len += len;
402 head_skb->len += len;
403 head_skb->truesize += truesize;
404 }
405 offset = buf - page_address(page);
406 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
407 put_page(page);
408 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
409 len, truesize);
410 } else {
411 skb_add_rx_frag(curr_skb, num_skb_frags, page,
412 offset, len, truesize);
413 }
414 }
415
416 ewma_add(&rq->mrg_avg_pkt_len, head_skb->len);
417 return head_skb;
418
419err_skb:
420 put_page(page);
421 while (--num_buf) {
422 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
423 if (unlikely(!ctx)) {
424 pr_debug("%s: rx error: %d buffers missing\n",
425 dev->name, num_buf);
426 dev->stats.rx_length_errors++;
427 break;
428 }
429 page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx));
430 put_page(page);
431 }
432err_buf:
433 dev->stats.rx_dropped++;
434 dev_kfree_skb(head_skb);
435 return NULL;
436}
437
438static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len)
439{
440 struct virtnet_info *vi = rq->vq->vdev->priv;
441 struct net_device *dev = vi->dev;
442 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
443 struct sk_buff *skb;
444 struct skb_vnet_hdr *hdr;
445
446 if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
447 pr_debug("%s: short packet %i\n", dev->name, len);
448 dev->stats.rx_length_errors++;
449 if (vi->mergeable_rx_bufs) {
450 unsigned long ctx = (unsigned long)buf;
451 void *base = mergeable_ctx_to_buf_address(ctx);
452 put_page(virt_to_head_page(base));
453 } else if (vi->big_packets) {
454 give_pages(rq, buf);
455 } else {
456 dev_kfree_skb(buf);
457 }
458 return;
459 }
460
461 if (vi->mergeable_rx_bufs)
462 skb = receive_mergeable(dev, rq, (unsigned long)buf, len);
463 else if (vi->big_packets)
464 skb = receive_big(dev, rq, buf, len);
465 else
466 skb = receive_small(buf, len);
467
468 if (unlikely(!skb))
469 return;
470
471 hdr = skb_vnet_hdr(skb);
472
473 u64_stats_update_begin(&stats->rx_syncp);
474 stats->rx_bytes += skb->len;
475 stats->rx_packets++;
476 u64_stats_update_end(&stats->rx_syncp);
477
478 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
479 pr_debug("Needs csum!\n");
480 if (!skb_partial_csum_set(skb,
481 hdr->hdr.csum_start,
482 hdr->hdr.csum_offset))
483 goto frame_err;
484 } else if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID) {
485 skb->ip_summed = CHECKSUM_UNNECESSARY;
486 }
487
488 skb->protocol = eth_type_trans(skb, dev);
489 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
490 ntohs(skb->protocol), skb->len, skb->pkt_type);
491
492 if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
493 pr_debug("GSO!\n");
494 switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
495 case VIRTIO_NET_HDR_GSO_TCPV4:
496 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
497 break;
498 case VIRTIO_NET_HDR_GSO_UDP:
499 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
500 break;
501 case VIRTIO_NET_HDR_GSO_TCPV6:
502 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
503 break;
504 default:
505 net_warn_ratelimited("%s: bad gso type %u.\n",
506 dev->name, hdr->hdr.gso_type);
507 goto frame_err;
508 }
509
510 if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
511 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
512
513 skb_shinfo(skb)->gso_size = hdr->hdr.gso_size;
514 if (skb_shinfo(skb)->gso_size == 0) {
515 net_warn_ratelimited("%s: zero gso size.\n", dev->name);
516 goto frame_err;
517 }
518
519 /* Header must be checked, and gso_segs computed. */
520 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
521 skb_shinfo(skb)->gso_segs = 0;
522 }
523
524 netif_receive_skb(skb);
525 return;
526
527frame_err:
528 dev->stats.rx_frame_errors++;
529 dev_kfree_skb(skb);
530}
531
532static int add_recvbuf_small(struct receive_queue *rq, gfp_t gfp)
533{
534 struct virtnet_info *vi = rq->vq->vdev->priv;
535 struct sk_buff *skb;
536 struct skb_vnet_hdr *hdr;
537 int err;
538
539 skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp);
540 if (unlikely(!skb))
541 return -ENOMEM;
542
543 skb_put(skb, GOOD_PACKET_LEN);
544
545 hdr = skb_vnet_hdr(skb);
546 sg_set_buf(rq->sg, &hdr->hdr, sizeof hdr->hdr);
547
548 skb_to_sgvec(skb, rq->sg + 1, 0, skb->len);
549
550 err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp);
551 if (err < 0)
552 dev_kfree_skb(skb);
553
554 return err;
555}
556
557static int add_recvbuf_big(struct receive_queue *rq, gfp_t gfp)
558{
559 struct page *first, *list = NULL;
560 char *p;
561 int i, err, offset;
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 virtio_net_hdr only due to QEMU bug */
587 sg_set_buf(&rq->sg[0], p, sizeof(struct virtio_net_hdr));
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
603static 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
613static 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 */
655static bool try_fill_recv(struct receive_queue *rq, gfp_t gfp)
656{
657 struct virtnet_info *vi = rq->vq->vdev->priv;
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(rq, gfp);
667 else
668 err = add_recvbuf_small(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
678static 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
690static 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
706static 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(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
728static int virtnet_poll(struct napi_struct *napi, int budget)
729{
730 struct receive_queue *rq =
731 container_of(napi, struct receive_queue, napi);
732 struct virtnet_info *vi = rq->vq->vdev->priv;
733 void *buf;
734 unsigned int r, len, received = 0;
735
736again:
737 while (received < budget &&
738 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
739 receive_buf(rq, buf, len);
740 received++;
741 }
742
743 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
744 if (!try_fill_recv(rq, GFP_ATOMIC))
745 schedule_delayed_work(&vi->refill, 0);
746 }
747
748 /* Out of packets? */
749 if (received < budget) {
750 r = virtqueue_enable_cb_prepare(rq->vq);
751 napi_complete(napi);
752 if (unlikely(virtqueue_poll(rq->vq, r)) &&
753 napi_schedule_prep(napi)) {
754 virtqueue_disable_cb(rq->vq);
755 __napi_schedule(napi);
756 goto again;
757 }
758 }
759
760 return received;
761}
762
763static int virtnet_open(struct net_device *dev)
764{
765 struct virtnet_info *vi = netdev_priv(dev);
766 int i;
767
768 for (i = 0; i < vi->max_queue_pairs; i++) {
769 if (i < vi->curr_queue_pairs)
770 /* Make sure we have some buffers: if oom use wq. */
771 if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
772 schedule_delayed_work(&vi->refill, 0);
773 virtnet_napi_enable(&vi->rq[i]);
774 }
775
776 return 0;
777}
778
779static void free_old_xmit_skbs(struct send_queue *sq)
780{
781 struct sk_buff *skb;
782 unsigned int len;
783 struct virtnet_info *vi = sq->vq->vdev->priv;
784 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
785
786 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
787 pr_debug("Sent skb %p\n", skb);
788
789 u64_stats_update_begin(&stats->tx_syncp);
790 stats->tx_bytes += skb->len;
791 stats->tx_packets++;
792 u64_stats_update_end(&stats->tx_syncp);
793
794 dev_kfree_skb_any(skb);
795 }
796}
797
798static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
799{
800 struct skb_vnet_hdr *hdr;
801 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
802 struct virtnet_info *vi = sq->vq->vdev->priv;
803 unsigned num_sg;
804 unsigned hdr_len;
805 bool can_push;
806
807 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
808 if (vi->mergeable_rx_bufs)
809 hdr_len = sizeof hdr->mhdr;
810 else
811 hdr_len = sizeof hdr->hdr;
812
813 can_push = vi->any_header_sg &&
814 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
815 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
816 /* Even if we can, don't push here yet as this would skew
817 * csum_start offset below. */
818 if (can_push)
819 hdr = (struct skb_vnet_hdr *)(skb->data - hdr_len);
820 else
821 hdr = skb_vnet_hdr(skb);
822
823 if (skb->ip_summed == CHECKSUM_PARTIAL) {
824 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
825 hdr->hdr.csum_start = skb_checksum_start_offset(skb);
826 hdr->hdr.csum_offset = skb->csum_offset;
827 } else {
828 hdr->hdr.flags = 0;
829 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
830 }
831
832 if (skb_is_gso(skb)) {
833 hdr->hdr.hdr_len = skb_headlen(skb);
834 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
835 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
836 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
837 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
838 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
839 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
840 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
841 else
842 BUG();
843 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
844 hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
845 } else {
846 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
847 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
848 }
849
850 if (vi->mergeable_rx_bufs)
851 hdr->mhdr.num_buffers = 0;
852
853 if (can_push) {
854 __skb_push(skb, hdr_len);
855 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
856 /* Pull header back to avoid skew in tx bytes calculations. */
857 __skb_pull(skb, hdr_len);
858 } else {
859 sg_set_buf(sq->sg, hdr, hdr_len);
860 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
861 }
862 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
863}
864
865static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
866{
867 struct virtnet_info *vi = netdev_priv(dev);
868 int qnum = skb_get_queue_mapping(skb);
869 struct send_queue *sq = &vi->sq[qnum];
870 int err;
871
872 /* Free up any pending old buffers before queueing new ones. */
873 free_old_xmit_skbs(sq);
874
875 /* Try to transmit */
876 err = xmit_skb(sq, skb);
877
878 /* This should not happen! */
879 if (unlikely(err)) {
880 dev->stats.tx_fifo_errors++;
881 if (net_ratelimit())
882 dev_warn(&dev->dev,
883 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
884 dev->stats.tx_dropped++;
885 dev_kfree_skb_any(skb);
886 return NETDEV_TX_OK;
887 }
888 virtqueue_kick(sq->vq);
889
890 /* Don't wait up for transmitted skbs to be freed. */
891 skb_orphan(skb);
892 nf_reset(skb);
893
894 /* Apparently nice girls don't return TX_BUSY; stop the queue
895 * before it gets out of hand. Naturally, this wastes entries. */
896 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
897 netif_stop_subqueue(dev, qnum);
898 if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
899 /* More just got used, free them then recheck. */
900 free_old_xmit_skbs(sq);
901 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
902 netif_start_subqueue(dev, qnum);
903 virtqueue_disable_cb(sq->vq);
904 }
905 }
906 }
907
908 return NETDEV_TX_OK;
909}
910
911/*
912 * Send command via the control virtqueue and check status. Commands
913 * supported by the hypervisor, as indicated by feature bits, should
914 * never fail unless improperly formatted.
915 */
916static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
917 struct scatterlist *out)
918{
919 struct scatterlist *sgs[4], hdr, stat;
920 struct virtio_net_ctrl_hdr ctrl;
921 virtio_net_ctrl_ack status = ~0;
922 unsigned out_num = 0, tmp;
923
924 /* Caller should know better */
925 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
926
927 ctrl.class = class;
928 ctrl.cmd = cmd;
929 /* Add header */
930 sg_init_one(&hdr, &ctrl, sizeof(ctrl));
931 sgs[out_num++] = &hdr;
932
933 if (out)
934 sgs[out_num++] = out;
935
936 /* Add return status. */
937 sg_init_one(&stat, &status, sizeof(status));
938 sgs[out_num] = &stat;
939
940 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
941 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
942
943 if (unlikely(!virtqueue_kick(vi->cvq)))
944 return status == VIRTIO_NET_OK;
945
946 /* Spin for a response, the kick causes an ioport write, trapping
947 * into the hypervisor, so the request should be handled immediately.
948 */
949 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
950 !virtqueue_is_broken(vi->cvq))
951 cpu_relax();
952
953 return status == VIRTIO_NET_OK;
954}
955
956static int virtnet_set_mac_address(struct net_device *dev, void *p)
957{
958 struct virtnet_info *vi = netdev_priv(dev);
959 struct virtio_device *vdev = vi->vdev;
960 int ret;
961 struct sockaddr *addr = p;
962 struct scatterlist sg;
963
964 ret = eth_prepare_mac_addr_change(dev, p);
965 if (ret)
966 return ret;
967
968 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
969 sg_init_one(&sg, addr->sa_data, dev->addr_len);
970 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
971 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
972 dev_warn(&vdev->dev,
973 "Failed to set mac address by vq command.\n");
974 return -EINVAL;
975 }
976 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
977 unsigned int i;
978
979 /* Naturally, this has an atomicity problem. */
980 for (i = 0; i < dev->addr_len; i++)
981 virtio_cwrite8(vdev,
982 offsetof(struct virtio_net_config, mac) +
983 i, addr->sa_data[i]);
984 }
985
986 eth_commit_mac_addr_change(dev, p);
987
988 return 0;
989}
990
991static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,
992 struct rtnl_link_stats64 *tot)
993{
994 struct virtnet_info *vi = netdev_priv(dev);
995 int cpu;
996 unsigned int start;
997
998 for_each_possible_cpu(cpu) {
999 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1000 u64 tpackets, tbytes, rpackets, rbytes;
1001
1002 do {
1003 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1004 tpackets = stats->tx_packets;
1005 tbytes = stats->tx_bytes;
1006 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1007
1008 do {
1009 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1010 rpackets = stats->rx_packets;
1011 rbytes = stats->rx_bytes;
1012 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1013
1014 tot->rx_packets += rpackets;
1015 tot->tx_packets += tpackets;
1016 tot->rx_bytes += rbytes;
1017 tot->tx_bytes += tbytes;
1018 }
1019
1020 tot->tx_dropped = dev->stats.tx_dropped;
1021 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1022 tot->rx_dropped = dev->stats.rx_dropped;
1023 tot->rx_length_errors = dev->stats.rx_length_errors;
1024 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1025
1026 return tot;
1027}
1028
1029#ifdef CONFIG_NET_POLL_CONTROLLER
1030static void virtnet_netpoll(struct net_device *dev)
1031{
1032 struct virtnet_info *vi = netdev_priv(dev);
1033 int i;
1034
1035 for (i = 0; i < vi->curr_queue_pairs; i++)
1036 napi_schedule(&vi->rq[i].napi);
1037}
1038#endif
1039
1040static void virtnet_ack_link_announce(struct virtnet_info *vi)
1041{
1042 rtnl_lock();
1043 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1044 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1045 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1046 rtnl_unlock();
1047}
1048
1049static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1050{
1051 struct scatterlist sg;
1052 struct virtio_net_ctrl_mq s;
1053 struct net_device *dev = vi->dev;
1054
1055 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1056 return 0;
1057
1058 s.virtqueue_pairs = queue_pairs;
1059 sg_init_one(&sg, &s, sizeof(s));
1060
1061 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1062 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1063 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1064 queue_pairs);
1065 return -EINVAL;
1066 } else {
1067 vi->curr_queue_pairs = queue_pairs;
1068 /* virtnet_open() will refill when device is going to up. */
1069 if (dev->flags & IFF_UP)
1070 schedule_delayed_work(&vi->refill, 0);
1071 }
1072
1073 return 0;
1074}
1075
1076static int virtnet_close(struct net_device *dev)
1077{
1078 struct virtnet_info *vi = netdev_priv(dev);
1079 int i;
1080
1081 /* Make sure refill_work doesn't re-enable napi! */
1082 cancel_delayed_work_sync(&vi->refill);
1083
1084 for (i = 0; i < vi->max_queue_pairs; i++)
1085 napi_disable(&vi->rq[i].napi);
1086
1087 return 0;
1088}
1089
1090static void virtnet_set_rx_mode(struct net_device *dev)
1091{
1092 struct virtnet_info *vi = netdev_priv(dev);
1093 struct scatterlist sg[2];
1094 u8 promisc, allmulti;
1095 struct virtio_net_ctrl_mac *mac_data;
1096 struct netdev_hw_addr *ha;
1097 int uc_count;
1098 int mc_count;
1099 void *buf;
1100 int i;
1101
1102 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1103 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1104 return;
1105
1106 promisc = ((dev->flags & IFF_PROMISC) != 0);
1107 allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1108
1109 sg_init_one(sg, &promisc, sizeof(promisc));
1110
1111 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1112 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1113 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1114 promisc ? "en" : "dis");
1115
1116 sg_init_one(sg, &allmulti, sizeof(allmulti));
1117
1118 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1119 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1120 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1121 allmulti ? "en" : "dis");
1122
1123 uc_count = netdev_uc_count(dev);
1124 mc_count = netdev_mc_count(dev);
1125 /* MAC filter - use one buffer for both lists */
1126 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1127 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1128 mac_data = buf;
1129 if (!buf)
1130 return;
1131
1132 sg_init_table(sg, 2);
1133
1134 /* Store the unicast list and count in the front of the buffer */
1135 mac_data->entries = uc_count;
1136 i = 0;
1137 netdev_for_each_uc_addr(ha, dev)
1138 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1139
1140 sg_set_buf(&sg[0], mac_data,
1141 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1142
1143 /* multicast list and count fill the end */
1144 mac_data = (void *)&mac_data->macs[uc_count][0];
1145
1146 mac_data->entries = mc_count;
1147 i = 0;
1148 netdev_for_each_mc_addr(ha, dev)
1149 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1150
1151 sg_set_buf(&sg[1], mac_data,
1152 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1153
1154 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1155 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1156 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1157
1158 kfree(buf);
1159}
1160
1161static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1162 __be16 proto, u16 vid)
1163{
1164 struct virtnet_info *vi = netdev_priv(dev);
1165 struct scatterlist sg;
1166
1167 sg_init_one(&sg, &vid, sizeof(vid));
1168
1169 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1170 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1171 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1172 return 0;
1173}
1174
1175static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1176 __be16 proto, u16 vid)
1177{
1178 struct virtnet_info *vi = netdev_priv(dev);
1179 struct scatterlist sg;
1180
1181 sg_init_one(&sg, &vid, sizeof(vid));
1182
1183 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1184 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1185 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1186 return 0;
1187}
1188
1189static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1190{
1191 int i;
1192
1193 if (vi->affinity_hint_set) {
1194 for (i = 0; i < vi->max_queue_pairs; i++) {
1195 virtqueue_set_affinity(vi->rq[i].vq, -1);
1196 virtqueue_set_affinity(vi->sq[i].vq, -1);
1197 }
1198
1199 vi->affinity_hint_set = false;
1200 }
1201}
1202
1203static void virtnet_set_affinity(struct virtnet_info *vi)
1204{
1205 int i;
1206 int cpu;
1207
1208 /* In multiqueue mode, when the number of cpu is equal to the number of
1209 * queue pairs, we let the queue pairs to be private to one cpu by
1210 * setting the affinity hint to eliminate the contention.
1211 */
1212 if (vi->curr_queue_pairs == 1 ||
1213 vi->max_queue_pairs != num_online_cpus()) {
1214 virtnet_clean_affinity(vi, -1);
1215 return;
1216 }
1217
1218 i = 0;
1219 for_each_online_cpu(cpu) {
1220 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1221 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1222 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1223 i++;
1224 }
1225
1226 vi->affinity_hint_set = true;
1227}
1228
1229static int virtnet_cpu_callback(struct notifier_block *nfb,
1230 unsigned long action, void *hcpu)
1231{
1232 struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb);
1233
1234 switch(action & ~CPU_TASKS_FROZEN) {
1235 case CPU_ONLINE:
1236 case CPU_DOWN_FAILED:
1237 case CPU_DEAD:
1238 virtnet_set_affinity(vi);
1239 break;
1240 case CPU_DOWN_PREPARE:
1241 virtnet_clean_affinity(vi, (long)hcpu);
1242 break;
1243 default:
1244 break;
1245 }
1246
1247 return NOTIFY_OK;
1248}
1249
1250static void virtnet_get_ringparam(struct net_device *dev,
1251 struct ethtool_ringparam *ring)
1252{
1253 struct virtnet_info *vi = netdev_priv(dev);
1254
1255 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1256 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1257 ring->rx_pending = ring->rx_max_pending;
1258 ring->tx_pending = ring->tx_max_pending;
1259}
1260
1261
1262static void virtnet_get_drvinfo(struct net_device *dev,
1263 struct ethtool_drvinfo *info)
1264{
1265 struct virtnet_info *vi = netdev_priv(dev);
1266 struct virtio_device *vdev = vi->vdev;
1267
1268 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1269 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1270 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1271
1272}
1273
1274/* TODO: Eliminate OOO packets during switching */
1275static int virtnet_set_channels(struct net_device *dev,
1276 struct ethtool_channels *channels)
1277{
1278 struct virtnet_info *vi = netdev_priv(dev);
1279 u16 queue_pairs = channels->combined_count;
1280 int err;
1281
1282 /* We don't support separate rx/tx channels.
1283 * We don't allow setting 'other' channels.
1284 */
1285 if (channels->rx_count || channels->tx_count || channels->other_count)
1286 return -EINVAL;
1287
1288 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1289 return -EINVAL;
1290
1291 get_online_cpus();
1292 err = virtnet_set_queues(vi, queue_pairs);
1293 if (!err) {
1294 netif_set_real_num_tx_queues(dev, queue_pairs);
1295 netif_set_real_num_rx_queues(dev, queue_pairs);
1296
1297 virtnet_set_affinity(vi);
1298 }
1299 put_online_cpus();
1300
1301 return err;
1302}
1303
1304static void virtnet_get_channels(struct net_device *dev,
1305 struct ethtool_channels *channels)
1306{
1307 struct virtnet_info *vi = netdev_priv(dev);
1308
1309 channels->combined_count = vi->curr_queue_pairs;
1310 channels->max_combined = vi->max_queue_pairs;
1311 channels->max_other = 0;
1312 channels->rx_count = 0;
1313 channels->tx_count = 0;
1314 channels->other_count = 0;
1315}
1316
1317static const struct ethtool_ops virtnet_ethtool_ops = {
1318 .get_drvinfo = virtnet_get_drvinfo,
1319 .get_link = ethtool_op_get_link,
1320 .get_ringparam = virtnet_get_ringparam,
1321 .set_channels = virtnet_set_channels,
1322 .get_channels = virtnet_get_channels,
1323};
1324
1325#define MIN_MTU 68
1326#define MAX_MTU 65535
1327
1328static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
1329{
1330 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
1331 return -EINVAL;
1332 dev->mtu = new_mtu;
1333 return 0;
1334}
1335
1336static const struct net_device_ops virtnet_netdev = {
1337 .ndo_open = virtnet_open,
1338 .ndo_stop = virtnet_close,
1339 .ndo_start_xmit = start_xmit,
1340 .ndo_validate_addr = eth_validate_addr,
1341 .ndo_set_mac_address = virtnet_set_mac_address,
1342 .ndo_set_rx_mode = virtnet_set_rx_mode,
1343 .ndo_change_mtu = virtnet_change_mtu,
1344 .ndo_get_stats64 = virtnet_stats,
1345 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
1346 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
1347#ifdef CONFIG_NET_POLL_CONTROLLER
1348 .ndo_poll_controller = virtnet_netpoll,
1349#endif
1350};
1351
1352static void virtnet_config_changed_work(struct work_struct *work)
1353{
1354 struct virtnet_info *vi =
1355 container_of(work, struct virtnet_info, config_work);
1356 u16 v;
1357
1358 mutex_lock(&vi->config_lock);
1359 if (!vi->config_enable)
1360 goto done;
1361
1362 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
1363 struct virtio_net_config, status, &v) < 0)
1364 goto done;
1365
1366 if (v & VIRTIO_NET_S_ANNOUNCE) {
1367 netdev_notify_peers(vi->dev);
1368 virtnet_ack_link_announce(vi);
1369 }
1370
1371 /* Ignore unknown (future) status bits */
1372 v &= VIRTIO_NET_S_LINK_UP;
1373
1374 if (vi->status == v)
1375 goto done;
1376
1377 vi->status = v;
1378
1379 if (vi->status & VIRTIO_NET_S_LINK_UP) {
1380 netif_carrier_on(vi->dev);
1381 netif_tx_wake_all_queues(vi->dev);
1382 } else {
1383 netif_carrier_off(vi->dev);
1384 netif_tx_stop_all_queues(vi->dev);
1385 }
1386done:
1387 mutex_unlock(&vi->config_lock);
1388}
1389
1390static void virtnet_config_changed(struct virtio_device *vdev)
1391{
1392 struct virtnet_info *vi = vdev->priv;
1393
1394 schedule_work(&vi->config_work);
1395}
1396
1397static void virtnet_free_queues(struct virtnet_info *vi)
1398{
1399 int i;
1400
1401 for (i = 0; i < vi->max_queue_pairs; i++)
1402 netif_napi_del(&vi->rq[i].napi);
1403
1404 kfree(vi->rq);
1405 kfree(vi->sq);
1406}
1407
1408static void free_receive_bufs(struct virtnet_info *vi)
1409{
1410 int i;
1411
1412 for (i = 0; i < vi->max_queue_pairs; i++) {
1413 while (vi->rq[i].pages)
1414 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
1415 }
1416}
1417
1418static void free_receive_page_frags(struct virtnet_info *vi)
1419{
1420 int i;
1421 for (i = 0; i < vi->max_queue_pairs; i++)
1422 if (vi->rq[i].alloc_frag.page)
1423 put_page(vi->rq[i].alloc_frag.page);
1424}
1425
1426static void free_unused_bufs(struct virtnet_info *vi)
1427{
1428 void *buf;
1429 int i;
1430
1431 for (i = 0; i < vi->max_queue_pairs; i++) {
1432 struct virtqueue *vq = vi->sq[i].vq;
1433 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
1434 dev_kfree_skb(buf);
1435 }
1436
1437 for (i = 0; i < vi->max_queue_pairs; i++) {
1438 struct virtqueue *vq = vi->rq[i].vq;
1439
1440 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
1441 if (vi->mergeable_rx_bufs) {
1442 unsigned long ctx = (unsigned long)buf;
1443 void *base = mergeable_ctx_to_buf_address(ctx);
1444 put_page(virt_to_head_page(base));
1445 } else if (vi->big_packets) {
1446 give_pages(&vi->rq[i], buf);
1447 } else {
1448 dev_kfree_skb(buf);
1449 }
1450 }
1451 }
1452}
1453
1454static void virtnet_del_vqs(struct virtnet_info *vi)
1455{
1456 struct virtio_device *vdev = vi->vdev;
1457
1458 virtnet_clean_affinity(vi, -1);
1459
1460 vdev->config->del_vqs(vdev);
1461
1462 virtnet_free_queues(vi);
1463}
1464
1465static int virtnet_find_vqs(struct virtnet_info *vi)
1466{
1467 vq_callback_t **callbacks;
1468 struct virtqueue **vqs;
1469 int ret = -ENOMEM;
1470 int i, total_vqs;
1471 const char **names;
1472
1473 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
1474 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
1475 * possible control vq.
1476 */
1477 total_vqs = vi->max_queue_pairs * 2 +
1478 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
1479
1480 /* Allocate space for find_vqs parameters */
1481 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
1482 if (!vqs)
1483 goto err_vq;
1484 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
1485 if (!callbacks)
1486 goto err_callback;
1487 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
1488 if (!names)
1489 goto err_names;
1490
1491 /* Parameters for control virtqueue, if any */
1492 if (vi->has_cvq) {
1493 callbacks[total_vqs - 1] = NULL;
1494 names[total_vqs - 1] = "control";
1495 }
1496
1497 /* Allocate/initialize parameters for send/receive virtqueues */
1498 for (i = 0; i < vi->max_queue_pairs; i++) {
1499 callbacks[rxq2vq(i)] = skb_recv_done;
1500 callbacks[txq2vq(i)] = skb_xmit_done;
1501 sprintf(vi->rq[i].name, "input.%d", i);
1502 sprintf(vi->sq[i].name, "output.%d", i);
1503 names[rxq2vq(i)] = vi->rq[i].name;
1504 names[txq2vq(i)] = vi->sq[i].name;
1505 }
1506
1507 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
1508 names);
1509 if (ret)
1510 goto err_find;
1511
1512 if (vi->has_cvq) {
1513 vi->cvq = vqs[total_vqs - 1];
1514 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
1515 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1516 }
1517
1518 for (i = 0; i < vi->max_queue_pairs; i++) {
1519 vi->rq[i].vq = vqs[rxq2vq(i)];
1520 vi->sq[i].vq = vqs[txq2vq(i)];
1521 }
1522
1523 kfree(names);
1524 kfree(callbacks);
1525 kfree(vqs);
1526
1527 return 0;
1528
1529err_find:
1530 kfree(names);
1531err_names:
1532 kfree(callbacks);
1533err_callback:
1534 kfree(vqs);
1535err_vq:
1536 return ret;
1537}
1538
1539static int virtnet_alloc_queues(struct virtnet_info *vi)
1540{
1541 int i;
1542
1543 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
1544 if (!vi->sq)
1545 goto err_sq;
1546 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
1547 if (!vi->rq)
1548 goto err_rq;
1549
1550 INIT_DELAYED_WORK(&vi->refill, refill_work);
1551 for (i = 0; i < vi->max_queue_pairs; i++) {
1552 vi->rq[i].pages = NULL;
1553 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
1554 napi_weight);
1555
1556 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
1557 ewma_init(&vi->rq[i].mrg_avg_pkt_len, 1, RECEIVE_AVG_WEIGHT);
1558 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
1559 }
1560
1561 return 0;
1562
1563err_rq:
1564 kfree(vi->sq);
1565err_sq:
1566 return -ENOMEM;
1567}
1568
1569static int init_vqs(struct virtnet_info *vi)
1570{
1571 int ret;
1572
1573 /* Allocate send & receive queues */
1574 ret = virtnet_alloc_queues(vi);
1575 if (ret)
1576 goto err;
1577
1578 ret = virtnet_find_vqs(vi);
1579 if (ret)
1580 goto err_free;
1581
1582 get_online_cpus();
1583 virtnet_set_affinity(vi);
1584 put_online_cpus();
1585
1586 return 0;
1587
1588err_free:
1589 virtnet_free_queues(vi);
1590err:
1591 return ret;
1592}
1593
1594#ifdef CONFIG_SYSFS
1595static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
1596 struct rx_queue_attribute *attribute, char *buf)
1597{
1598 struct virtnet_info *vi = netdev_priv(queue->dev);
1599 unsigned int queue_index = get_netdev_rx_queue_index(queue);
1600 struct ewma *avg;
1601
1602 BUG_ON(queue_index >= vi->max_queue_pairs);
1603 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
1604 return sprintf(buf, "%u\n", get_mergeable_buf_len(avg));
1605}
1606
1607static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
1608 __ATTR_RO(mergeable_rx_buffer_size);
1609
1610static struct attribute *virtio_net_mrg_rx_attrs[] = {
1611 &mergeable_rx_buffer_size_attribute.attr,
1612 NULL
1613};
1614
1615static const struct attribute_group virtio_net_mrg_rx_group = {
1616 .name = "virtio_net",
1617 .attrs = virtio_net_mrg_rx_attrs
1618};
1619#endif
1620
1621static int virtnet_probe(struct virtio_device *vdev)
1622{
1623 int i, err;
1624 struct net_device *dev;
1625 struct virtnet_info *vi;
1626 u16 max_queue_pairs;
1627
1628 /* Find if host supports multiqueue virtio_net device */
1629 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
1630 struct virtio_net_config,
1631 max_virtqueue_pairs, &max_queue_pairs);
1632
1633 /* We need at least 2 queue's */
1634 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
1635 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
1636 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
1637 max_queue_pairs = 1;
1638
1639 /* Allocate ourselves a network device with room for our info */
1640 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
1641 if (!dev)
1642 return -ENOMEM;
1643
1644 /* Set up network device as normal. */
1645 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
1646 dev->netdev_ops = &virtnet_netdev;
1647 dev->features = NETIF_F_HIGHDMA;
1648
1649 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
1650 SET_NETDEV_DEV(dev, &vdev->dev);
1651
1652 /* Do we support "hardware" checksums? */
1653 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
1654 /* This opens up the world of extra features. */
1655 dev->hw_features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1656 if (csum)
1657 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1658
1659 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
1660 dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
1661 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
1662 }
1663 /* Individual feature bits: what can host handle? */
1664 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
1665 dev->hw_features |= NETIF_F_TSO;
1666 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
1667 dev->hw_features |= NETIF_F_TSO6;
1668 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
1669 dev->hw_features |= NETIF_F_TSO_ECN;
1670 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
1671 dev->hw_features |= NETIF_F_UFO;
1672
1673 if (gso)
1674 dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
1675 /* (!csum && gso) case will be fixed by register_netdev() */
1676 }
1677 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
1678 dev->features |= NETIF_F_RXCSUM;
1679
1680 dev->vlan_features = dev->features;
1681
1682 /* Configuration may specify what MAC to use. Otherwise random. */
1683 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
1684 virtio_cread_bytes(vdev,
1685 offsetof(struct virtio_net_config, mac),
1686 dev->dev_addr, dev->addr_len);
1687 else
1688 eth_hw_addr_random(dev);
1689
1690 /* Set up our device-specific information */
1691 vi = netdev_priv(dev);
1692 vi->dev = dev;
1693 vi->vdev = vdev;
1694 vdev->priv = vi;
1695 vi->stats = alloc_percpu(struct virtnet_stats);
1696 err = -ENOMEM;
1697 if (vi->stats == NULL)
1698 goto free;
1699
1700 for_each_possible_cpu(i) {
1701 struct virtnet_stats *virtnet_stats;
1702 virtnet_stats = per_cpu_ptr(vi->stats, i);
1703 u64_stats_init(&virtnet_stats->tx_syncp);
1704 u64_stats_init(&virtnet_stats->rx_syncp);
1705 }
1706
1707 mutex_init(&vi->config_lock);
1708 vi->config_enable = true;
1709 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
1710
1711 /* If we can receive ANY GSO packets, we must allocate large ones. */
1712 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1713 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1714 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
1715 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
1716 vi->big_packets = true;
1717
1718 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
1719 vi->mergeable_rx_bufs = true;
1720
1721 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT))
1722 vi->any_header_sg = true;
1723
1724 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
1725 vi->has_cvq = true;
1726
1727 /* Use single tx/rx queue pair as default */
1728 vi->curr_queue_pairs = 1;
1729 vi->max_queue_pairs = max_queue_pairs;
1730
1731 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
1732 err = init_vqs(vi);
1733 if (err)
1734 goto free_stats;
1735
1736#ifdef CONFIG_SYSFS
1737 if (vi->mergeable_rx_bufs)
1738 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
1739#endif
1740 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
1741 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
1742
1743 err = register_netdev(dev);
1744 if (err) {
1745 pr_debug("virtio_net: registering device failed\n");
1746 goto free_vqs;
1747 }
1748
1749 /* Last of all, set up some receive buffers. */
1750 for (i = 0; i < vi->curr_queue_pairs; i++) {
1751 try_fill_recv(&vi->rq[i], GFP_KERNEL);
1752
1753 /* If we didn't even get one input buffer, we're useless. */
1754 if (vi->rq[i].vq->num_free ==
1755 virtqueue_get_vring_size(vi->rq[i].vq)) {
1756 free_unused_bufs(vi);
1757 err = -ENOMEM;
1758 goto free_recv_bufs;
1759 }
1760 }
1761
1762 vi->nb.notifier_call = &virtnet_cpu_callback;
1763 err = register_hotcpu_notifier(&vi->nb);
1764 if (err) {
1765 pr_debug("virtio_net: registering cpu notifier failed\n");
1766 goto free_recv_bufs;
1767 }
1768
1769 /* Assume link up if device can't report link status,
1770 otherwise get link status from config. */
1771 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
1772 netif_carrier_off(dev);
1773 schedule_work(&vi->config_work);
1774 } else {
1775 vi->status = VIRTIO_NET_S_LINK_UP;
1776 netif_carrier_on(dev);
1777 }
1778
1779 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
1780 dev->name, max_queue_pairs);
1781
1782 return 0;
1783
1784free_recv_bufs:
1785 free_receive_bufs(vi);
1786 unregister_netdev(dev);
1787free_vqs:
1788 cancel_delayed_work_sync(&vi->refill);
1789 free_receive_page_frags(vi);
1790 virtnet_del_vqs(vi);
1791free_stats:
1792 free_percpu(vi->stats);
1793free:
1794 free_netdev(dev);
1795 return err;
1796}
1797
1798static void remove_vq_common(struct virtnet_info *vi)
1799{
1800 vi->vdev->config->reset(vi->vdev);
1801
1802 /* Free unused buffers in both send and recv, if any. */
1803 free_unused_bufs(vi);
1804
1805 free_receive_bufs(vi);
1806
1807 free_receive_page_frags(vi);
1808
1809 virtnet_del_vqs(vi);
1810}
1811
1812static void virtnet_remove(struct virtio_device *vdev)
1813{
1814 struct virtnet_info *vi = vdev->priv;
1815
1816 unregister_hotcpu_notifier(&vi->nb);
1817
1818 /* Prevent config work handler from accessing the device. */
1819 mutex_lock(&vi->config_lock);
1820 vi->config_enable = false;
1821 mutex_unlock(&vi->config_lock);
1822
1823 unregister_netdev(vi->dev);
1824
1825 remove_vq_common(vi);
1826
1827 flush_work(&vi->config_work);
1828
1829 free_percpu(vi->stats);
1830 free_netdev(vi->dev);
1831}
1832
1833#ifdef CONFIG_PM_SLEEP
1834static int virtnet_freeze(struct virtio_device *vdev)
1835{
1836 struct virtnet_info *vi = vdev->priv;
1837 int i;
1838
1839 unregister_hotcpu_notifier(&vi->nb);
1840
1841 /* Prevent config work handler from accessing the device */
1842 mutex_lock(&vi->config_lock);
1843 vi->config_enable = false;
1844 mutex_unlock(&vi->config_lock);
1845
1846 netif_device_detach(vi->dev);
1847 cancel_delayed_work_sync(&vi->refill);
1848
1849 if (netif_running(vi->dev))
1850 for (i = 0; i < vi->max_queue_pairs; i++) {
1851 napi_disable(&vi->rq[i].napi);
1852 netif_napi_del(&vi->rq[i].napi);
1853 }
1854
1855 remove_vq_common(vi);
1856
1857 flush_work(&vi->config_work);
1858
1859 return 0;
1860}
1861
1862static int virtnet_restore(struct virtio_device *vdev)
1863{
1864 struct virtnet_info *vi = vdev->priv;
1865 int err, i;
1866
1867 err = init_vqs(vi);
1868 if (err)
1869 return err;
1870
1871 if (netif_running(vi->dev)) {
1872 for (i = 0; i < vi->curr_queue_pairs; i++)
1873 if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
1874 schedule_delayed_work(&vi->refill, 0);
1875
1876 for (i = 0; i < vi->max_queue_pairs; i++)
1877 virtnet_napi_enable(&vi->rq[i]);
1878 }
1879
1880 netif_device_attach(vi->dev);
1881
1882 mutex_lock(&vi->config_lock);
1883 vi->config_enable = true;
1884 mutex_unlock(&vi->config_lock);
1885
1886 rtnl_lock();
1887 virtnet_set_queues(vi, vi->curr_queue_pairs);
1888 rtnl_unlock();
1889
1890 err = register_hotcpu_notifier(&vi->nb);
1891 if (err)
1892 return err;
1893
1894 return 0;
1895}
1896#endif
1897
1898static struct virtio_device_id id_table[] = {
1899 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
1900 { 0 },
1901};
1902
1903static unsigned int features[] = {
1904 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
1905 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
1906 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
1907 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
1908 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
1909 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
1910 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
1911 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ,
1912 VIRTIO_NET_F_CTRL_MAC_ADDR,
1913 VIRTIO_F_ANY_LAYOUT,
1914};
1915
1916static struct virtio_driver virtio_net_driver = {
1917 .feature_table = features,
1918 .feature_table_size = ARRAY_SIZE(features),
1919 .driver.name = KBUILD_MODNAME,
1920 .driver.owner = THIS_MODULE,
1921 .id_table = id_table,
1922 .probe = virtnet_probe,
1923 .remove = virtnet_remove,
1924 .config_changed = virtnet_config_changed,
1925#ifdef CONFIG_PM_SLEEP
1926 .freeze = virtnet_freeze,
1927 .restore = virtnet_restore,
1928#endif
1929};
1930
1931module_virtio_driver(virtio_net_driver);
1932
1933MODULE_DEVICE_TABLE(virtio, id_table);
1934MODULE_DESCRIPTION("Virtio network driver");
1935MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* A network driver using virtio.
3 *
4 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
5 */
6//#define DEBUG
7#include <linux/netdevice.h>
8#include <linux/etherdevice.h>
9#include <linux/ethtool.h>
10#include <linux/module.h>
11#include <linux/virtio.h>
12#include <linux/virtio_net.h>
13#include <linux/bpf.h>
14#include <linux/bpf_trace.h>
15#include <linux/scatterlist.h>
16#include <linux/if_vlan.h>
17#include <linux/slab.h>
18#include <linux/cpu.h>
19#include <linux/average.h>
20#include <linux/filter.h>
21#include <linux/kernel.h>
22#include <net/route.h>
23#include <net/xdp.h>
24#include <net/net_failover.h>
25
26static int napi_weight = NAPI_POLL_WEIGHT;
27module_param(napi_weight, int, 0444);
28
29static bool csum = true, gso = true, napi_tx = true;
30module_param(csum, bool, 0444);
31module_param(gso, bool, 0444);
32module_param(napi_tx, bool, 0644);
33
34/* FIXME: MTU in config. */
35#define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
36#define GOOD_COPY_LEN 128
37
38#define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
39
40/* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
41#define VIRTIO_XDP_HEADROOM 256
42
43/* Separating two types of XDP xmit */
44#define VIRTIO_XDP_TX BIT(0)
45#define VIRTIO_XDP_REDIR BIT(1)
46
47#define VIRTIO_XDP_FLAG BIT(0)
48
49/* RX packet size EWMA. The average packet size is used to determine the packet
50 * buffer size when refilling RX rings. As the entire RX ring may be refilled
51 * at once, the weight is chosen so that the EWMA will be insensitive to short-
52 * term, transient changes in packet size.
53 */
54DECLARE_EWMA(pkt_len, 0, 64)
55
56#define VIRTNET_DRIVER_VERSION "1.0.0"
57
58static const unsigned long guest_offloads[] = {
59 VIRTIO_NET_F_GUEST_TSO4,
60 VIRTIO_NET_F_GUEST_TSO6,
61 VIRTIO_NET_F_GUEST_ECN,
62 VIRTIO_NET_F_GUEST_UFO,
63 VIRTIO_NET_F_GUEST_CSUM,
64 VIRTIO_NET_F_GUEST_USO4,
65 VIRTIO_NET_F_GUEST_USO6
66};
67
68#define GUEST_OFFLOAD_GRO_HW_MASK ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
69 (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
70 (1ULL << VIRTIO_NET_F_GUEST_ECN) | \
71 (1ULL << VIRTIO_NET_F_GUEST_UFO) | \
72 (1ULL << VIRTIO_NET_F_GUEST_USO4) | \
73 (1ULL << VIRTIO_NET_F_GUEST_USO6))
74
75struct virtnet_stat_desc {
76 char desc[ETH_GSTRING_LEN];
77 size_t offset;
78};
79
80struct virtnet_sq_stats {
81 struct u64_stats_sync syncp;
82 u64 packets;
83 u64 bytes;
84 u64 xdp_tx;
85 u64 xdp_tx_drops;
86 u64 kicks;
87 u64 tx_timeouts;
88};
89
90struct virtnet_rq_stats {
91 struct u64_stats_sync syncp;
92 u64 packets;
93 u64 bytes;
94 u64 drops;
95 u64 xdp_packets;
96 u64 xdp_tx;
97 u64 xdp_redirects;
98 u64 xdp_drops;
99 u64 kicks;
100};
101
102#define VIRTNET_SQ_STAT(m) offsetof(struct virtnet_sq_stats, m)
103#define VIRTNET_RQ_STAT(m) offsetof(struct virtnet_rq_stats, m)
104
105static const struct virtnet_stat_desc virtnet_sq_stats_desc[] = {
106 { "packets", VIRTNET_SQ_STAT(packets) },
107 { "bytes", VIRTNET_SQ_STAT(bytes) },
108 { "xdp_tx", VIRTNET_SQ_STAT(xdp_tx) },
109 { "xdp_tx_drops", VIRTNET_SQ_STAT(xdp_tx_drops) },
110 { "kicks", VIRTNET_SQ_STAT(kicks) },
111 { "tx_timeouts", VIRTNET_SQ_STAT(tx_timeouts) },
112};
113
114static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = {
115 { "packets", VIRTNET_RQ_STAT(packets) },
116 { "bytes", VIRTNET_RQ_STAT(bytes) },
117 { "drops", VIRTNET_RQ_STAT(drops) },
118 { "xdp_packets", VIRTNET_RQ_STAT(xdp_packets) },
119 { "xdp_tx", VIRTNET_RQ_STAT(xdp_tx) },
120 { "xdp_redirects", VIRTNET_RQ_STAT(xdp_redirects) },
121 { "xdp_drops", VIRTNET_RQ_STAT(xdp_drops) },
122 { "kicks", VIRTNET_RQ_STAT(kicks) },
123};
124
125#define VIRTNET_SQ_STATS_LEN ARRAY_SIZE(virtnet_sq_stats_desc)
126#define VIRTNET_RQ_STATS_LEN ARRAY_SIZE(virtnet_rq_stats_desc)
127
128/* Internal representation of a send virtqueue */
129struct send_queue {
130 /* Virtqueue associated with this send _queue */
131 struct virtqueue *vq;
132
133 /* TX: fragments + linear part + virtio header */
134 struct scatterlist sg[MAX_SKB_FRAGS + 2];
135
136 /* Name of the send queue: output.$index */
137 char name[40];
138
139 struct virtnet_sq_stats stats;
140
141 struct napi_struct napi;
142
143 /* Record whether sq is in reset state. */
144 bool reset;
145};
146
147/* Internal representation of a receive virtqueue */
148struct receive_queue {
149 /* Virtqueue associated with this receive_queue */
150 struct virtqueue *vq;
151
152 struct napi_struct napi;
153
154 struct bpf_prog __rcu *xdp_prog;
155
156 struct virtnet_rq_stats stats;
157
158 /* Chain pages by the private ptr. */
159 struct page *pages;
160
161 /* Average packet length for mergeable receive buffers. */
162 struct ewma_pkt_len mrg_avg_pkt_len;
163
164 /* Page frag for packet buffer allocation. */
165 struct page_frag alloc_frag;
166
167 /* RX: fragments + linear part + virtio header */
168 struct scatterlist sg[MAX_SKB_FRAGS + 2];
169
170 /* Min single buffer size for mergeable buffers case. */
171 unsigned int min_buf_len;
172
173 /* Name of this receive queue: input.$index */
174 char name[40];
175
176 struct xdp_rxq_info xdp_rxq;
177};
178
179/* This structure can contain rss message with maximum settings for indirection table and keysize
180 * Note, that default structure that describes RSS configuration virtio_net_rss_config
181 * contains same info but can't handle table values.
182 * In any case, structure would be passed to virtio hw through sg_buf split by parts
183 * because table sizes may be differ according to the device configuration.
184 */
185#define VIRTIO_NET_RSS_MAX_KEY_SIZE 40
186#define VIRTIO_NET_RSS_MAX_TABLE_LEN 128
187struct virtio_net_ctrl_rss {
188 u32 hash_types;
189 u16 indirection_table_mask;
190 u16 unclassified_queue;
191 u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN];
192 u16 max_tx_vq;
193 u8 hash_key_length;
194 u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE];
195};
196
197/* Control VQ buffers: protected by the rtnl lock */
198struct control_buf {
199 struct virtio_net_ctrl_hdr hdr;
200 virtio_net_ctrl_ack status;
201 struct virtio_net_ctrl_mq mq;
202 u8 promisc;
203 u8 allmulti;
204 __virtio16 vid;
205 __virtio64 offloads;
206 struct virtio_net_ctrl_rss rss;
207};
208
209struct virtnet_info {
210 struct virtio_device *vdev;
211 struct virtqueue *cvq;
212 struct net_device *dev;
213 struct send_queue *sq;
214 struct receive_queue *rq;
215 unsigned int status;
216
217 /* Max # of queue pairs supported by the device */
218 u16 max_queue_pairs;
219
220 /* # of queue pairs currently used by the driver */
221 u16 curr_queue_pairs;
222
223 /* # of XDP queue pairs currently used by the driver */
224 u16 xdp_queue_pairs;
225
226 /* xdp_queue_pairs may be 0, when xdp is already loaded. So add this. */
227 bool xdp_enabled;
228
229 /* I like... big packets and I cannot lie! */
230 bool big_packets;
231
232 /* number of sg entries allocated for big packets */
233 unsigned int big_packets_num_skbfrags;
234
235 /* Host will merge rx buffers for big packets (shake it! shake it!) */
236 bool mergeable_rx_bufs;
237
238 /* Host supports rss and/or hash report */
239 bool has_rss;
240 bool has_rss_hash_report;
241 u8 rss_key_size;
242 u16 rss_indir_table_size;
243 u32 rss_hash_types_supported;
244 u32 rss_hash_types_saved;
245
246 /* Has control virtqueue */
247 bool has_cvq;
248
249 /* Host can handle any s/g split between our header and packet data */
250 bool any_header_sg;
251
252 /* Packet virtio header size */
253 u8 hdr_len;
254
255 /* Work struct for delayed refilling if we run low on memory. */
256 struct delayed_work refill;
257
258 /* Is delayed refill enabled? */
259 bool refill_enabled;
260
261 /* The lock to synchronize the access to refill_enabled */
262 spinlock_t refill_lock;
263
264 /* Work struct for config space updates */
265 struct work_struct config_work;
266
267 /* Does the affinity hint is set for virtqueues? */
268 bool affinity_hint_set;
269
270 /* CPU hotplug instances for online & dead */
271 struct hlist_node node;
272 struct hlist_node node_dead;
273
274 struct control_buf *ctrl;
275
276 /* Ethtool settings */
277 u8 duplex;
278 u32 speed;
279
280 /* Interrupt coalescing settings */
281 u32 tx_usecs;
282 u32 rx_usecs;
283 u32 tx_max_packets;
284 u32 rx_max_packets;
285
286 unsigned long guest_offloads;
287 unsigned long guest_offloads_capable;
288
289 /* failover when STANDBY feature enabled */
290 struct failover *failover;
291};
292
293struct padded_vnet_hdr {
294 struct virtio_net_hdr_v1_hash hdr;
295 /*
296 * hdr is in a separate sg buffer, and data sg buffer shares same page
297 * with this header sg. This padding makes next sg 16 byte aligned
298 * after the header.
299 */
300 char padding[12];
301};
302
303static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf);
304static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf);
305
306static bool is_xdp_frame(void *ptr)
307{
308 return (unsigned long)ptr & VIRTIO_XDP_FLAG;
309}
310
311static void *xdp_to_ptr(struct xdp_frame *ptr)
312{
313 return (void *)((unsigned long)ptr | VIRTIO_XDP_FLAG);
314}
315
316static struct xdp_frame *ptr_to_xdp(void *ptr)
317{
318 return (struct xdp_frame *)((unsigned long)ptr & ~VIRTIO_XDP_FLAG);
319}
320
321/* Converting between virtqueue no. and kernel tx/rx queue no.
322 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
323 */
324static int vq2txq(struct virtqueue *vq)
325{
326 return (vq->index - 1) / 2;
327}
328
329static int txq2vq(int txq)
330{
331 return txq * 2 + 1;
332}
333
334static int vq2rxq(struct virtqueue *vq)
335{
336 return vq->index / 2;
337}
338
339static int rxq2vq(int rxq)
340{
341 return rxq * 2;
342}
343
344static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
345{
346 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
347}
348
349/*
350 * private is used to chain pages for big packets, put the whole
351 * most recent used list in the beginning for reuse
352 */
353static void give_pages(struct receive_queue *rq, struct page *page)
354{
355 struct page *end;
356
357 /* Find end of list, sew whole thing into vi->rq.pages. */
358 for (end = page; end->private; end = (struct page *)end->private);
359 end->private = (unsigned long)rq->pages;
360 rq->pages = page;
361}
362
363static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
364{
365 struct page *p = rq->pages;
366
367 if (p) {
368 rq->pages = (struct page *)p->private;
369 /* clear private here, it is used to chain pages */
370 p->private = 0;
371 } else
372 p = alloc_page(gfp_mask);
373 return p;
374}
375
376static void enable_delayed_refill(struct virtnet_info *vi)
377{
378 spin_lock_bh(&vi->refill_lock);
379 vi->refill_enabled = true;
380 spin_unlock_bh(&vi->refill_lock);
381}
382
383static void disable_delayed_refill(struct virtnet_info *vi)
384{
385 spin_lock_bh(&vi->refill_lock);
386 vi->refill_enabled = false;
387 spin_unlock_bh(&vi->refill_lock);
388}
389
390static void virtqueue_napi_schedule(struct napi_struct *napi,
391 struct virtqueue *vq)
392{
393 if (napi_schedule_prep(napi)) {
394 virtqueue_disable_cb(vq);
395 __napi_schedule(napi);
396 }
397}
398
399static void virtqueue_napi_complete(struct napi_struct *napi,
400 struct virtqueue *vq, int processed)
401{
402 int opaque;
403
404 opaque = virtqueue_enable_cb_prepare(vq);
405 if (napi_complete_done(napi, processed)) {
406 if (unlikely(virtqueue_poll(vq, opaque)))
407 virtqueue_napi_schedule(napi, vq);
408 } else {
409 virtqueue_disable_cb(vq);
410 }
411}
412
413static void skb_xmit_done(struct virtqueue *vq)
414{
415 struct virtnet_info *vi = vq->vdev->priv;
416 struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
417
418 /* Suppress further interrupts. */
419 virtqueue_disable_cb(vq);
420
421 if (napi->weight)
422 virtqueue_napi_schedule(napi, vq);
423 else
424 /* We were probably waiting for more output buffers. */
425 netif_wake_subqueue(vi->dev, vq2txq(vq));
426}
427
428#define MRG_CTX_HEADER_SHIFT 22
429static void *mergeable_len_to_ctx(unsigned int truesize,
430 unsigned int headroom)
431{
432 return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize);
433}
434
435static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
436{
437 return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
438}
439
440static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
441{
442 return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
443}
444
445/* Called from bottom half context */
446static struct sk_buff *page_to_skb(struct virtnet_info *vi,
447 struct receive_queue *rq,
448 struct page *page, unsigned int offset,
449 unsigned int len, unsigned int truesize,
450 bool hdr_valid, unsigned int metasize,
451 unsigned int headroom)
452{
453 struct sk_buff *skb;
454 struct virtio_net_hdr_mrg_rxbuf *hdr;
455 unsigned int copy, hdr_len, hdr_padded_len;
456 struct page *page_to_free = NULL;
457 int tailroom, shinfo_size;
458 char *p, *hdr_p, *buf;
459
460 p = page_address(page) + offset;
461 hdr_p = p;
462
463 hdr_len = vi->hdr_len;
464 if (vi->mergeable_rx_bufs)
465 hdr_padded_len = hdr_len;
466 else
467 hdr_padded_len = sizeof(struct padded_vnet_hdr);
468
469 /* If headroom is not 0, there is an offset between the beginning of the
470 * data and the allocated space, otherwise the data and the allocated
471 * space are aligned.
472 *
473 * Buffers with headroom use PAGE_SIZE as alloc size, see
474 * add_recvbuf_mergeable() + get_mergeable_buf_len()
475 */
476 truesize = headroom ? PAGE_SIZE : truesize;
477 tailroom = truesize - headroom;
478 buf = p - headroom;
479
480 len -= hdr_len;
481 offset += hdr_padded_len;
482 p += hdr_padded_len;
483 tailroom -= hdr_padded_len + len;
484
485 shinfo_size = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
486
487 /* copy small packet so we can reuse these pages */
488 if (!NET_IP_ALIGN && len > GOOD_COPY_LEN && tailroom >= shinfo_size) {
489 skb = build_skb(buf, truesize);
490 if (unlikely(!skb))
491 return NULL;
492
493 skb_reserve(skb, p - buf);
494 skb_put(skb, len);
495
496 page = (struct page *)page->private;
497 if (page)
498 give_pages(rq, page);
499 goto ok;
500 }
501
502 /* copy small packet so we can reuse these pages for small data */
503 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
504 if (unlikely(!skb))
505 return NULL;
506
507 /* Copy all frame if it fits skb->head, otherwise
508 * we let virtio_net_hdr_to_skb() and GRO pull headers as needed.
509 */
510 if (len <= skb_tailroom(skb))
511 copy = len;
512 else
513 copy = ETH_HLEN + metasize;
514 skb_put_data(skb, p, copy);
515
516 len -= copy;
517 offset += copy;
518
519 if (vi->mergeable_rx_bufs) {
520 if (len)
521 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
522 else
523 page_to_free = page;
524 goto ok;
525 }
526
527 /*
528 * Verify that we can indeed put this data into a skb.
529 * This is here to handle cases when the device erroneously
530 * tries to receive more than is possible. This is usually
531 * the case of a broken device.
532 */
533 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
534 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
535 dev_kfree_skb(skb);
536 return NULL;
537 }
538 BUG_ON(offset >= PAGE_SIZE);
539 while (len) {
540 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
541 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
542 frag_size, truesize);
543 len -= frag_size;
544 page = (struct page *)page->private;
545 offset = 0;
546 }
547
548 if (page)
549 give_pages(rq, page);
550
551ok:
552 /* hdr_valid means no XDP, so we can copy the vnet header */
553 if (hdr_valid) {
554 hdr = skb_vnet_hdr(skb);
555 memcpy(hdr, hdr_p, hdr_len);
556 }
557 if (page_to_free)
558 put_page(page_to_free);
559
560 if (metasize) {
561 __skb_pull(skb, metasize);
562 skb_metadata_set(skb, metasize);
563 }
564
565 return skb;
566}
567
568static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
569 struct send_queue *sq,
570 struct xdp_frame *xdpf)
571{
572 struct virtio_net_hdr_mrg_rxbuf *hdr;
573 int err;
574
575 if (unlikely(xdpf->headroom < vi->hdr_len))
576 return -EOVERFLOW;
577
578 /* Make room for virtqueue hdr (also change xdpf->headroom?) */
579 xdpf->data -= vi->hdr_len;
580 /* Zero header and leave csum up to XDP layers */
581 hdr = xdpf->data;
582 memset(hdr, 0, vi->hdr_len);
583 xdpf->len += vi->hdr_len;
584
585 sg_init_one(sq->sg, xdpf->data, xdpf->len);
586
587 err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp_to_ptr(xdpf),
588 GFP_ATOMIC);
589 if (unlikely(err))
590 return -ENOSPC; /* Caller handle free/refcnt */
591
592 return 0;
593}
594
595/* when vi->curr_queue_pairs > nr_cpu_ids, the txq/sq is only used for xdp tx on
596 * the current cpu, so it does not need to be locked.
597 *
598 * Here we use marco instead of inline functions because we have to deal with
599 * three issues at the same time: 1. the choice of sq. 2. judge and execute the
600 * lock/unlock of txq 3. make sparse happy. It is difficult for two inline
601 * functions to perfectly solve these three problems at the same time.
602 */
603#define virtnet_xdp_get_sq(vi) ({ \
604 int cpu = smp_processor_id(); \
605 struct netdev_queue *txq; \
606 typeof(vi) v = (vi); \
607 unsigned int qp; \
608 \
609 if (v->curr_queue_pairs > nr_cpu_ids) { \
610 qp = v->curr_queue_pairs - v->xdp_queue_pairs; \
611 qp += cpu; \
612 txq = netdev_get_tx_queue(v->dev, qp); \
613 __netif_tx_acquire(txq); \
614 } else { \
615 qp = cpu % v->curr_queue_pairs; \
616 txq = netdev_get_tx_queue(v->dev, qp); \
617 __netif_tx_lock(txq, cpu); \
618 } \
619 v->sq + qp; \
620})
621
622#define virtnet_xdp_put_sq(vi, q) { \
623 struct netdev_queue *txq; \
624 typeof(vi) v = (vi); \
625 \
626 txq = netdev_get_tx_queue(v->dev, (q) - v->sq); \
627 if (v->curr_queue_pairs > nr_cpu_ids) \
628 __netif_tx_release(txq); \
629 else \
630 __netif_tx_unlock(txq); \
631}
632
633static int virtnet_xdp_xmit(struct net_device *dev,
634 int n, struct xdp_frame **frames, u32 flags)
635{
636 struct virtnet_info *vi = netdev_priv(dev);
637 struct receive_queue *rq = vi->rq;
638 struct bpf_prog *xdp_prog;
639 struct send_queue *sq;
640 unsigned int len;
641 int packets = 0;
642 int bytes = 0;
643 int nxmit = 0;
644 int kicks = 0;
645 void *ptr;
646 int ret;
647 int i;
648
649 /* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this
650 * indicate XDP resources have been successfully allocated.
651 */
652 xdp_prog = rcu_access_pointer(rq->xdp_prog);
653 if (!xdp_prog)
654 return -ENXIO;
655
656 sq = virtnet_xdp_get_sq(vi);
657
658 if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
659 ret = -EINVAL;
660 goto out;
661 }
662
663 /* Free up any pending old buffers before queueing new ones. */
664 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
665 if (likely(is_xdp_frame(ptr))) {
666 struct xdp_frame *frame = ptr_to_xdp(ptr);
667
668 bytes += frame->len;
669 xdp_return_frame(frame);
670 } else {
671 struct sk_buff *skb = ptr;
672
673 bytes += skb->len;
674 napi_consume_skb(skb, false);
675 }
676 packets++;
677 }
678
679 for (i = 0; i < n; i++) {
680 struct xdp_frame *xdpf = frames[i];
681
682 if (__virtnet_xdp_xmit_one(vi, sq, xdpf))
683 break;
684 nxmit++;
685 }
686 ret = nxmit;
687
688 if (flags & XDP_XMIT_FLUSH) {
689 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
690 kicks = 1;
691 }
692out:
693 u64_stats_update_begin(&sq->stats.syncp);
694 sq->stats.bytes += bytes;
695 sq->stats.packets += packets;
696 sq->stats.xdp_tx += n;
697 sq->stats.xdp_tx_drops += n - nxmit;
698 sq->stats.kicks += kicks;
699 u64_stats_update_end(&sq->stats.syncp);
700
701 virtnet_xdp_put_sq(vi, sq);
702 return ret;
703}
704
705static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
706{
707 return vi->xdp_enabled ? VIRTIO_XDP_HEADROOM : 0;
708}
709
710/* We copy the packet for XDP in the following cases:
711 *
712 * 1) Packet is scattered across multiple rx buffers.
713 * 2) Headroom space is insufficient.
714 *
715 * This is inefficient but it's a temporary condition that
716 * we hit right after XDP is enabled and until queue is refilled
717 * with large buffers with sufficient headroom - so it should affect
718 * at most queue size packets.
719 * Afterwards, the conditions to enable
720 * XDP should preclude the underlying device from sending packets
721 * across multiple buffers (num_buf > 1), and we make sure buffers
722 * have enough headroom.
723 */
724static struct page *xdp_linearize_page(struct receive_queue *rq,
725 u16 *num_buf,
726 struct page *p,
727 int offset,
728 int page_off,
729 unsigned int *len)
730{
731 struct page *page = alloc_page(GFP_ATOMIC);
732
733 if (!page)
734 return NULL;
735
736 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
737 page_off += *len;
738
739 while (--*num_buf) {
740 int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
741 unsigned int buflen;
742 void *buf;
743 int off;
744
745 buf = virtqueue_get_buf(rq->vq, &buflen);
746 if (unlikely(!buf))
747 goto err_buf;
748
749 p = virt_to_head_page(buf);
750 off = buf - page_address(p);
751
752 /* guard against a misconfigured or uncooperative backend that
753 * is sending packet larger than the MTU.
754 */
755 if ((page_off + buflen + tailroom) > PAGE_SIZE) {
756 put_page(p);
757 goto err_buf;
758 }
759
760 memcpy(page_address(page) + page_off,
761 page_address(p) + off, buflen);
762 page_off += buflen;
763 put_page(p);
764 }
765
766 /* Headroom does not contribute to packet length */
767 *len = page_off - VIRTIO_XDP_HEADROOM;
768 return page;
769err_buf:
770 __free_pages(page, 0);
771 return NULL;
772}
773
774static struct sk_buff *receive_small(struct net_device *dev,
775 struct virtnet_info *vi,
776 struct receive_queue *rq,
777 void *buf, void *ctx,
778 unsigned int len,
779 unsigned int *xdp_xmit,
780 struct virtnet_rq_stats *stats)
781{
782 struct sk_buff *skb;
783 struct bpf_prog *xdp_prog;
784 unsigned int xdp_headroom = (unsigned long)ctx;
785 unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
786 unsigned int headroom = vi->hdr_len + header_offset;
787 unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
788 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
789 struct page *page = virt_to_head_page(buf);
790 unsigned int delta = 0;
791 struct page *xdp_page;
792 int err;
793 unsigned int metasize = 0;
794
795 len -= vi->hdr_len;
796 stats->bytes += len;
797
798 if (unlikely(len > GOOD_PACKET_LEN)) {
799 pr_debug("%s: rx error: len %u exceeds max size %d\n",
800 dev->name, len, GOOD_PACKET_LEN);
801 dev->stats.rx_length_errors++;
802 goto err;
803 }
804
805 if (likely(!vi->xdp_enabled)) {
806 xdp_prog = NULL;
807 goto skip_xdp;
808 }
809
810 rcu_read_lock();
811 xdp_prog = rcu_dereference(rq->xdp_prog);
812 if (xdp_prog) {
813 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
814 struct xdp_frame *xdpf;
815 struct xdp_buff xdp;
816 void *orig_data;
817 u32 act;
818
819 if (unlikely(hdr->hdr.gso_type))
820 goto err_xdp;
821
822 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
823 int offset = buf - page_address(page) + header_offset;
824 unsigned int tlen = len + vi->hdr_len;
825 u16 num_buf = 1;
826
827 xdp_headroom = virtnet_get_headroom(vi);
828 header_offset = VIRTNET_RX_PAD + xdp_headroom;
829 headroom = vi->hdr_len + header_offset;
830 buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
831 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
832 xdp_page = xdp_linearize_page(rq, &num_buf, page,
833 offset, header_offset,
834 &tlen);
835 if (!xdp_page)
836 goto err_xdp;
837
838 buf = page_address(xdp_page);
839 put_page(page);
840 page = xdp_page;
841 }
842
843 xdp_init_buff(&xdp, buflen, &rq->xdp_rxq);
844 xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len,
845 xdp_headroom, len, true);
846 orig_data = xdp.data;
847 act = bpf_prog_run_xdp(xdp_prog, &xdp);
848 stats->xdp_packets++;
849
850 switch (act) {
851 case XDP_PASS:
852 /* Recalculate length in case bpf program changed it */
853 delta = orig_data - xdp.data;
854 len = xdp.data_end - xdp.data;
855 metasize = xdp.data - xdp.data_meta;
856 break;
857 case XDP_TX:
858 stats->xdp_tx++;
859 xdpf = xdp_convert_buff_to_frame(&xdp);
860 if (unlikely(!xdpf))
861 goto err_xdp;
862 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
863 if (unlikely(!err)) {
864 xdp_return_frame_rx_napi(xdpf);
865 } else if (unlikely(err < 0)) {
866 trace_xdp_exception(vi->dev, xdp_prog, act);
867 goto err_xdp;
868 }
869 *xdp_xmit |= VIRTIO_XDP_TX;
870 rcu_read_unlock();
871 goto xdp_xmit;
872 case XDP_REDIRECT:
873 stats->xdp_redirects++;
874 err = xdp_do_redirect(dev, &xdp, xdp_prog);
875 if (err)
876 goto err_xdp;
877 *xdp_xmit |= VIRTIO_XDP_REDIR;
878 rcu_read_unlock();
879 goto xdp_xmit;
880 default:
881 bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act);
882 fallthrough;
883 case XDP_ABORTED:
884 trace_xdp_exception(vi->dev, xdp_prog, act);
885 goto err_xdp;
886 case XDP_DROP:
887 goto err_xdp;
888 }
889 }
890 rcu_read_unlock();
891
892skip_xdp:
893 skb = build_skb(buf, buflen);
894 if (!skb)
895 goto err;
896 skb_reserve(skb, headroom - delta);
897 skb_put(skb, len);
898 if (!xdp_prog) {
899 buf += header_offset;
900 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
901 } /* keep zeroed vnet hdr since XDP is loaded */
902
903 if (metasize)
904 skb_metadata_set(skb, metasize);
905
906 return skb;
907
908err_xdp:
909 rcu_read_unlock();
910 stats->xdp_drops++;
911err:
912 stats->drops++;
913 put_page(page);
914xdp_xmit:
915 return NULL;
916}
917
918static struct sk_buff *receive_big(struct net_device *dev,
919 struct virtnet_info *vi,
920 struct receive_queue *rq,
921 void *buf,
922 unsigned int len,
923 struct virtnet_rq_stats *stats)
924{
925 struct page *page = buf;
926 struct sk_buff *skb =
927 page_to_skb(vi, rq, page, 0, len, PAGE_SIZE, true, 0, 0);
928
929 stats->bytes += len - vi->hdr_len;
930 if (unlikely(!skb))
931 goto err;
932
933 return skb;
934
935err:
936 stats->drops++;
937 give_pages(rq, page);
938 return NULL;
939}
940
941static struct sk_buff *receive_mergeable(struct net_device *dev,
942 struct virtnet_info *vi,
943 struct receive_queue *rq,
944 void *buf,
945 void *ctx,
946 unsigned int len,
947 unsigned int *xdp_xmit,
948 struct virtnet_rq_stats *stats)
949{
950 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
951 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
952 struct page *page = virt_to_head_page(buf);
953 int offset = buf - page_address(page);
954 struct sk_buff *head_skb, *curr_skb;
955 struct bpf_prog *xdp_prog;
956 unsigned int truesize = mergeable_ctx_to_truesize(ctx);
957 unsigned int headroom = mergeable_ctx_to_headroom(ctx);
958 unsigned int metasize = 0;
959 unsigned int frame_sz;
960 int err;
961
962 head_skb = NULL;
963 stats->bytes += len - vi->hdr_len;
964
965 if (unlikely(len > truesize)) {
966 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
967 dev->name, len, (unsigned long)ctx);
968 dev->stats.rx_length_errors++;
969 goto err_skb;
970 }
971
972 if (likely(!vi->xdp_enabled)) {
973 xdp_prog = NULL;
974 goto skip_xdp;
975 }
976
977 rcu_read_lock();
978 xdp_prog = rcu_dereference(rq->xdp_prog);
979 if (xdp_prog) {
980 struct xdp_frame *xdpf;
981 struct page *xdp_page;
982 struct xdp_buff xdp;
983 void *data;
984 u32 act;
985
986 /* Transient failure which in theory could occur if
987 * in-flight packets from before XDP was enabled reach
988 * the receive path after XDP is loaded.
989 */
990 if (unlikely(hdr->hdr.gso_type))
991 goto err_xdp;
992
993 /* Buffers with headroom use PAGE_SIZE as alloc size,
994 * see add_recvbuf_mergeable() + get_mergeable_buf_len()
995 */
996 frame_sz = headroom ? PAGE_SIZE : truesize;
997
998 /* This happens when rx buffer size is underestimated
999 * or headroom is not enough because of the buffer
1000 * was refilled before XDP is set. This should only
1001 * happen for the first several packets, so we don't
1002 * care much about its performance.
1003 */
1004 if (unlikely(num_buf > 1 ||
1005 headroom < virtnet_get_headroom(vi))) {
1006 /* linearize data for XDP */
1007 xdp_page = xdp_linearize_page(rq, &num_buf,
1008 page, offset,
1009 VIRTIO_XDP_HEADROOM,
1010 &len);
1011 frame_sz = PAGE_SIZE;
1012
1013 if (!xdp_page)
1014 goto err_xdp;
1015 offset = VIRTIO_XDP_HEADROOM;
1016 } else {
1017 xdp_page = page;
1018 }
1019
1020 /* Allow consuming headroom but reserve enough space to push
1021 * the descriptor on if we get an XDP_TX return code.
1022 */
1023 data = page_address(xdp_page) + offset;
1024 xdp_init_buff(&xdp, frame_sz - vi->hdr_len, &rq->xdp_rxq);
1025 xdp_prepare_buff(&xdp, data - VIRTIO_XDP_HEADROOM + vi->hdr_len,
1026 VIRTIO_XDP_HEADROOM, len - vi->hdr_len, true);
1027
1028 act = bpf_prog_run_xdp(xdp_prog, &xdp);
1029 stats->xdp_packets++;
1030
1031 switch (act) {
1032 case XDP_PASS:
1033 metasize = xdp.data - xdp.data_meta;
1034
1035 /* recalculate offset to account for any header
1036 * adjustments and minus the metasize to copy the
1037 * metadata in page_to_skb(). Note other cases do not
1038 * build an skb and avoid using offset
1039 */
1040 offset = xdp.data - page_address(xdp_page) -
1041 vi->hdr_len - metasize;
1042
1043 /* recalculate len if xdp.data, xdp.data_end or
1044 * xdp.data_meta were adjusted
1045 */
1046 len = xdp.data_end - xdp.data + vi->hdr_len + metasize;
1047
1048 /* recalculate headroom if xdp.data or xdp_data_meta
1049 * were adjusted, note that offset should always point
1050 * to the start of the reserved bytes for virtio_net
1051 * header which are followed by xdp.data, that means
1052 * that offset is equal to the headroom (when buf is
1053 * starting at the beginning of the page, otherwise
1054 * there is a base offset inside the page) but it's used
1055 * with a different starting point (buf start) than
1056 * xdp.data (buf start + vnet hdr size). If xdp.data or
1057 * data_meta were adjusted by the xdp prog then the
1058 * headroom size has changed and so has the offset, we
1059 * can use data_hard_start, which points at buf start +
1060 * vnet hdr size, to calculate the new headroom and use
1061 * it later to compute buf start in page_to_skb()
1062 */
1063 headroom = xdp.data - xdp.data_hard_start - metasize;
1064
1065 /* We can only create skb based on xdp_page. */
1066 if (unlikely(xdp_page != page)) {
1067 rcu_read_unlock();
1068 put_page(page);
1069 head_skb = page_to_skb(vi, rq, xdp_page, offset,
1070 len, PAGE_SIZE, false,
1071 metasize,
1072 headroom);
1073 return head_skb;
1074 }
1075 break;
1076 case XDP_TX:
1077 stats->xdp_tx++;
1078 xdpf = xdp_convert_buff_to_frame(&xdp);
1079 if (unlikely(!xdpf)) {
1080 if (unlikely(xdp_page != page))
1081 put_page(xdp_page);
1082 goto err_xdp;
1083 }
1084 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
1085 if (unlikely(!err)) {
1086 xdp_return_frame_rx_napi(xdpf);
1087 } else if (unlikely(err < 0)) {
1088 trace_xdp_exception(vi->dev, xdp_prog, act);
1089 if (unlikely(xdp_page != page))
1090 put_page(xdp_page);
1091 goto err_xdp;
1092 }
1093 *xdp_xmit |= VIRTIO_XDP_TX;
1094 if (unlikely(xdp_page != page))
1095 put_page(page);
1096 rcu_read_unlock();
1097 goto xdp_xmit;
1098 case XDP_REDIRECT:
1099 stats->xdp_redirects++;
1100 err = xdp_do_redirect(dev, &xdp, xdp_prog);
1101 if (err) {
1102 if (unlikely(xdp_page != page))
1103 put_page(xdp_page);
1104 goto err_xdp;
1105 }
1106 *xdp_xmit |= VIRTIO_XDP_REDIR;
1107 if (unlikely(xdp_page != page))
1108 put_page(page);
1109 rcu_read_unlock();
1110 goto xdp_xmit;
1111 default:
1112 bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act);
1113 fallthrough;
1114 case XDP_ABORTED:
1115 trace_xdp_exception(vi->dev, xdp_prog, act);
1116 fallthrough;
1117 case XDP_DROP:
1118 if (unlikely(xdp_page != page))
1119 __free_pages(xdp_page, 0);
1120 goto err_xdp;
1121 }
1122 }
1123 rcu_read_unlock();
1124
1125skip_xdp:
1126 head_skb = page_to_skb(vi, rq, page, offset, len, truesize, !xdp_prog,
1127 metasize, headroom);
1128 curr_skb = head_skb;
1129
1130 if (unlikely(!curr_skb))
1131 goto err_skb;
1132 while (--num_buf) {
1133 int num_skb_frags;
1134
1135 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
1136 if (unlikely(!buf)) {
1137 pr_debug("%s: rx error: %d buffers out of %d missing\n",
1138 dev->name, num_buf,
1139 virtio16_to_cpu(vi->vdev,
1140 hdr->num_buffers));
1141 dev->stats.rx_length_errors++;
1142 goto err_buf;
1143 }
1144
1145 stats->bytes += len;
1146 page = virt_to_head_page(buf);
1147
1148 truesize = mergeable_ctx_to_truesize(ctx);
1149 if (unlikely(len > truesize)) {
1150 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
1151 dev->name, len, (unsigned long)ctx);
1152 dev->stats.rx_length_errors++;
1153 goto err_skb;
1154 }
1155
1156 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
1157 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
1158 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
1159
1160 if (unlikely(!nskb))
1161 goto err_skb;
1162 if (curr_skb == head_skb)
1163 skb_shinfo(curr_skb)->frag_list = nskb;
1164 else
1165 curr_skb->next = nskb;
1166 curr_skb = nskb;
1167 head_skb->truesize += nskb->truesize;
1168 num_skb_frags = 0;
1169 }
1170 if (curr_skb != head_skb) {
1171 head_skb->data_len += len;
1172 head_skb->len += len;
1173 head_skb->truesize += truesize;
1174 }
1175 offset = buf - page_address(page);
1176 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
1177 put_page(page);
1178 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
1179 len, truesize);
1180 } else {
1181 skb_add_rx_frag(curr_skb, num_skb_frags, page,
1182 offset, len, truesize);
1183 }
1184 }
1185
1186 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
1187 return head_skb;
1188
1189err_xdp:
1190 rcu_read_unlock();
1191 stats->xdp_drops++;
1192err_skb:
1193 put_page(page);
1194 while (num_buf-- > 1) {
1195 buf = virtqueue_get_buf(rq->vq, &len);
1196 if (unlikely(!buf)) {
1197 pr_debug("%s: rx error: %d buffers missing\n",
1198 dev->name, num_buf);
1199 dev->stats.rx_length_errors++;
1200 break;
1201 }
1202 stats->bytes += len;
1203 page = virt_to_head_page(buf);
1204 put_page(page);
1205 }
1206err_buf:
1207 stats->drops++;
1208 dev_kfree_skb(head_skb);
1209xdp_xmit:
1210 return NULL;
1211}
1212
1213static void virtio_skb_set_hash(const struct virtio_net_hdr_v1_hash *hdr_hash,
1214 struct sk_buff *skb)
1215{
1216 enum pkt_hash_types rss_hash_type;
1217
1218 if (!hdr_hash || !skb)
1219 return;
1220
1221 switch (__le16_to_cpu(hdr_hash->hash_report)) {
1222 case VIRTIO_NET_HASH_REPORT_TCPv4:
1223 case VIRTIO_NET_HASH_REPORT_UDPv4:
1224 case VIRTIO_NET_HASH_REPORT_TCPv6:
1225 case VIRTIO_NET_HASH_REPORT_UDPv6:
1226 case VIRTIO_NET_HASH_REPORT_TCPv6_EX:
1227 case VIRTIO_NET_HASH_REPORT_UDPv6_EX:
1228 rss_hash_type = PKT_HASH_TYPE_L4;
1229 break;
1230 case VIRTIO_NET_HASH_REPORT_IPv4:
1231 case VIRTIO_NET_HASH_REPORT_IPv6:
1232 case VIRTIO_NET_HASH_REPORT_IPv6_EX:
1233 rss_hash_type = PKT_HASH_TYPE_L3;
1234 break;
1235 case VIRTIO_NET_HASH_REPORT_NONE:
1236 default:
1237 rss_hash_type = PKT_HASH_TYPE_NONE;
1238 }
1239 skb_set_hash(skb, __le32_to_cpu(hdr_hash->hash_value), rss_hash_type);
1240}
1241
1242static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
1243 void *buf, unsigned int len, void **ctx,
1244 unsigned int *xdp_xmit,
1245 struct virtnet_rq_stats *stats)
1246{
1247 struct net_device *dev = vi->dev;
1248 struct sk_buff *skb;
1249 struct virtio_net_hdr_mrg_rxbuf *hdr;
1250
1251 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
1252 pr_debug("%s: short packet %i\n", dev->name, len);
1253 dev->stats.rx_length_errors++;
1254 if (vi->mergeable_rx_bufs) {
1255 put_page(virt_to_head_page(buf));
1256 } else if (vi->big_packets) {
1257 give_pages(rq, buf);
1258 } else {
1259 put_page(virt_to_head_page(buf));
1260 }
1261 return;
1262 }
1263
1264 if (vi->mergeable_rx_bufs)
1265 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit,
1266 stats);
1267 else if (vi->big_packets)
1268 skb = receive_big(dev, vi, rq, buf, len, stats);
1269 else
1270 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats);
1271
1272 if (unlikely(!skb))
1273 return;
1274
1275 hdr = skb_vnet_hdr(skb);
1276 if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report)
1277 virtio_skb_set_hash((const struct virtio_net_hdr_v1_hash *)hdr, skb);
1278
1279 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
1280 skb->ip_summed = CHECKSUM_UNNECESSARY;
1281
1282 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
1283 virtio_is_little_endian(vi->vdev))) {
1284 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
1285 dev->name, hdr->hdr.gso_type,
1286 hdr->hdr.gso_size);
1287 goto frame_err;
1288 }
1289
1290 skb_record_rx_queue(skb, vq2rxq(rq->vq));
1291 skb->protocol = eth_type_trans(skb, dev);
1292 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
1293 ntohs(skb->protocol), skb->len, skb->pkt_type);
1294
1295 napi_gro_receive(&rq->napi, skb);
1296 return;
1297
1298frame_err:
1299 dev->stats.rx_frame_errors++;
1300 dev_kfree_skb(skb);
1301}
1302
1303/* Unlike mergeable buffers, all buffers are allocated to the
1304 * same size, except for the headroom. For this reason we do
1305 * not need to use mergeable_len_to_ctx here - it is enough
1306 * to store the headroom as the context ignoring the truesize.
1307 */
1308static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
1309 gfp_t gfp)
1310{
1311 struct page_frag *alloc_frag = &rq->alloc_frag;
1312 char *buf;
1313 unsigned int xdp_headroom = virtnet_get_headroom(vi);
1314 void *ctx = (void *)(unsigned long)xdp_headroom;
1315 int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
1316 int err;
1317
1318 len = SKB_DATA_ALIGN(len) +
1319 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
1320 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
1321 return -ENOMEM;
1322
1323 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1324 get_page(alloc_frag->page);
1325 alloc_frag->offset += len;
1326 sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
1327 vi->hdr_len + GOOD_PACKET_LEN);
1328 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1329 if (err < 0)
1330 put_page(virt_to_head_page(buf));
1331 return err;
1332}
1333
1334static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
1335 gfp_t gfp)
1336{
1337 struct page *first, *list = NULL;
1338 char *p;
1339 int i, err, offset;
1340
1341 sg_init_table(rq->sg, vi->big_packets_num_skbfrags + 2);
1342
1343 /* page in rq->sg[vi->big_packets_num_skbfrags + 1] is list tail */
1344 for (i = vi->big_packets_num_skbfrags + 1; i > 1; --i) {
1345 first = get_a_page(rq, gfp);
1346 if (!first) {
1347 if (list)
1348 give_pages(rq, list);
1349 return -ENOMEM;
1350 }
1351 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
1352
1353 /* chain new page in list head to match sg */
1354 first->private = (unsigned long)list;
1355 list = first;
1356 }
1357
1358 first = get_a_page(rq, gfp);
1359 if (!first) {
1360 give_pages(rq, list);
1361 return -ENOMEM;
1362 }
1363 p = page_address(first);
1364
1365 /* rq->sg[0], rq->sg[1] share the same page */
1366 /* a separated rq->sg[0] for header - required in case !any_header_sg */
1367 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
1368
1369 /* rq->sg[1] for data packet, from offset */
1370 offset = sizeof(struct padded_vnet_hdr);
1371 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
1372
1373 /* chain first in list head */
1374 first->private = (unsigned long)list;
1375 err = virtqueue_add_inbuf(rq->vq, rq->sg, vi->big_packets_num_skbfrags + 2,
1376 first, gfp);
1377 if (err < 0)
1378 give_pages(rq, first);
1379
1380 return err;
1381}
1382
1383static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
1384 struct ewma_pkt_len *avg_pkt_len,
1385 unsigned int room)
1386{
1387 struct virtnet_info *vi = rq->vq->vdev->priv;
1388 const size_t hdr_len = vi->hdr_len;
1389 unsigned int len;
1390
1391 if (room)
1392 return PAGE_SIZE - room;
1393
1394 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
1395 rq->min_buf_len, PAGE_SIZE - hdr_len);
1396
1397 return ALIGN(len, L1_CACHE_BYTES);
1398}
1399
1400static int add_recvbuf_mergeable(struct virtnet_info *vi,
1401 struct receive_queue *rq, gfp_t gfp)
1402{
1403 struct page_frag *alloc_frag = &rq->alloc_frag;
1404 unsigned int headroom = virtnet_get_headroom(vi);
1405 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1406 unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
1407 char *buf;
1408 void *ctx;
1409 int err;
1410 unsigned int len, hole;
1411
1412 /* Extra tailroom is needed to satisfy XDP's assumption. This
1413 * means rx frags coalescing won't work, but consider we've
1414 * disabled GSO for XDP, it won't be a big issue.
1415 */
1416 len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room);
1417 if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp)))
1418 return -ENOMEM;
1419
1420 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1421 buf += headroom; /* advance address leaving hole at front of pkt */
1422 get_page(alloc_frag->page);
1423 alloc_frag->offset += len + room;
1424 hole = alloc_frag->size - alloc_frag->offset;
1425 if (hole < len + room) {
1426 /* To avoid internal fragmentation, if there is very likely not
1427 * enough space for another buffer, add the remaining space to
1428 * the current buffer.
1429 */
1430 len += hole;
1431 alloc_frag->offset += hole;
1432 }
1433
1434 sg_init_one(rq->sg, buf, len);
1435 ctx = mergeable_len_to_ctx(len, headroom);
1436 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1437 if (err < 0)
1438 put_page(virt_to_head_page(buf));
1439
1440 return err;
1441}
1442
1443/*
1444 * Returns false if we couldn't fill entirely (OOM).
1445 *
1446 * Normally run in the receive path, but can also be run from ndo_open
1447 * before we're receiving packets, or from refill_work which is
1448 * careful to disable receiving (using napi_disable).
1449 */
1450static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
1451 gfp_t gfp)
1452{
1453 int err;
1454 bool oom;
1455
1456 do {
1457 if (vi->mergeable_rx_bufs)
1458 err = add_recvbuf_mergeable(vi, rq, gfp);
1459 else if (vi->big_packets)
1460 err = add_recvbuf_big(vi, rq, gfp);
1461 else
1462 err = add_recvbuf_small(vi, rq, gfp);
1463
1464 oom = err == -ENOMEM;
1465 if (err)
1466 break;
1467 } while (rq->vq->num_free);
1468 if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
1469 unsigned long flags;
1470
1471 flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
1472 rq->stats.kicks++;
1473 u64_stats_update_end_irqrestore(&rq->stats.syncp, flags);
1474 }
1475
1476 return !oom;
1477}
1478
1479static void skb_recv_done(struct virtqueue *rvq)
1480{
1481 struct virtnet_info *vi = rvq->vdev->priv;
1482 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
1483
1484 virtqueue_napi_schedule(&rq->napi, rvq);
1485}
1486
1487static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
1488{
1489 napi_enable(napi);
1490
1491 /* If all buffers were filled by other side before we napi_enabled, we
1492 * won't get another interrupt, so process any outstanding packets now.
1493 * Call local_bh_enable after to trigger softIRQ processing.
1494 */
1495 local_bh_disable();
1496 virtqueue_napi_schedule(napi, vq);
1497 local_bh_enable();
1498}
1499
1500static void virtnet_napi_tx_enable(struct virtnet_info *vi,
1501 struct virtqueue *vq,
1502 struct napi_struct *napi)
1503{
1504 if (!napi->weight)
1505 return;
1506
1507 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1508 * enable the feature if this is likely affine with the transmit path.
1509 */
1510 if (!vi->affinity_hint_set) {
1511 napi->weight = 0;
1512 return;
1513 }
1514
1515 return virtnet_napi_enable(vq, napi);
1516}
1517
1518static void virtnet_napi_tx_disable(struct napi_struct *napi)
1519{
1520 if (napi->weight)
1521 napi_disable(napi);
1522}
1523
1524static void refill_work(struct work_struct *work)
1525{
1526 struct virtnet_info *vi =
1527 container_of(work, struct virtnet_info, refill.work);
1528 bool still_empty;
1529 int i;
1530
1531 for (i = 0; i < vi->curr_queue_pairs; i++) {
1532 struct receive_queue *rq = &vi->rq[i];
1533
1534 napi_disable(&rq->napi);
1535 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1536 virtnet_napi_enable(rq->vq, &rq->napi);
1537
1538 /* In theory, this can happen: if we don't get any buffers in
1539 * we will *never* try to fill again.
1540 */
1541 if (still_empty)
1542 schedule_delayed_work(&vi->refill, HZ/2);
1543 }
1544}
1545
1546static int virtnet_receive(struct receive_queue *rq, int budget,
1547 unsigned int *xdp_xmit)
1548{
1549 struct virtnet_info *vi = rq->vq->vdev->priv;
1550 struct virtnet_rq_stats stats = {};
1551 unsigned int len;
1552 void *buf;
1553 int i;
1554
1555 if (!vi->big_packets || vi->mergeable_rx_bufs) {
1556 void *ctx;
1557
1558 while (stats.packets < budget &&
1559 (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1560 receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats);
1561 stats.packets++;
1562 }
1563 } else {
1564 while (stats.packets < budget &&
1565 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1566 receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats);
1567 stats.packets++;
1568 }
1569 }
1570
1571 if (rq->vq->num_free > min((unsigned int)budget, virtqueue_get_vring_size(rq->vq)) / 2) {
1572 if (!try_fill_recv(vi, rq, GFP_ATOMIC)) {
1573 spin_lock(&vi->refill_lock);
1574 if (vi->refill_enabled)
1575 schedule_delayed_work(&vi->refill, 0);
1576 spin_unlock(&vi->refill_lock);
1577 }
1578 }
1579
1580 u64_stats_update_begin(&rq->stats.syncp);
1581 for (i = 0; i < VIRTNET_RQ_STATS_LEN; i++) {
1582 size_t offset = virtnet_rq_stats_desc[i].offset;
1583 u64 *item;
1584
1585 item = (u64 *)((u8 *)&rq->stats + offset);
1586 *item += *(u64 *)((u8 *)&stats + offset);
1587 }
1588 u64_stats_update_end(&rq->stats.syncp);
1589
1590 return stats.packets;
1591}
1592
1593static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi)
1594{
1595 unsigned int len;
1596 unsigned int packets = 0;
1597 unsigned int bytes = 0;
1598 void *ptr;
1599
1600 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1601 if (likely(!is_xdp_frame(ptr))) {
1602 struct sk_buff *skb = ptr;
1603
1604 pr_debug("Sent skb %p\n", skb);
1605
1606 bytes += skb->len;
1607 napi_consume_skb(skb, in_napi);
1608 } else {
1609 struct xdp_frame *frame = ptr_to_xdp(ptr);
1610
1611 bytes += frame->len;
1612 xdp_return_frame(frame);
1613 }
1614 packets++;
1615 }
1616
1617 /* Avoid overhead when no packets have been processed
1618 * happens when called speculatively from start_xmit.
1619 */
1620 if (!packets)
1621 return;
1622
1623 u64_stats_update_begin(&sq->stats.syncp);
1624 sq->stats.bytes += bytes;
1625 sq->stats.packets += packets;
1626 u64_stats_update_end(&sq->stats.syncp);
1627}
1628
1629static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
1630{
1631 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
1632 return false;
1633 else if (q < vi->curr_queue_pairs)
1634 return true;
1635 else
1636 return false;
1637}
1638
1639static void virtnet_poll_cleantx(struct receive_queue *rq)
1640{
1641 struct virtnet_info *vi = rq->vq->vdev->priv;
1642 unsigned int index = vq2rxq(rq->vq);
1643 struct send_queue *sq = &vi->sq[index];
1644 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1645
1646 if (!sq->napi.weight || is_xdp_raw_buffer_queue(vi, index))
1647 return;
1648
1649 if (__netif_tx_trylock(txq)) {
1650 if (sq->reset) {
1651 __netif_tx_unlock(txq);
1652 return;
1653 }
1654
1655 do {
1656 virtqueue_disable_cb(sq->vq);
1657 free_old_xmit_skbs(sq, true);
1658 } while (unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
1659
1660 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1661 netif_tx_wake_queue(txq);
1662
1663 __netif_tx_unlock(txq);
1664 }
1665}
1666
1667static int virtnet_poll(struct napi_struct *napi, int budget)
1668{
1669 struct receive_queue *rq =
1670 container_of(napi, struct receive_queue, napi);
1671 struct virtnet_info *vi = rq->vq->vdev->priv;
1672 struct send_queue *sq;
1673 unsigned int received;
1674 unsigned int xdp_xmit = 0;
1675
1676 virtnet_poll_cleantx(rq);
1677
1678 received = virtnet_receive(rq, budget, &xdp_xmit);
1679
1680 if (xdp_xmit & VIRTIO_XDP_REDIR)
1681 xdp_do_flush();
1682
1683 /* Out of packets? */
1684 if (received < budget)
1685 virtqueue_napi_complete(napi, rq->vq, received);
1686
1687 if (xdp_xmit & VIRTIO_XDP_TX) {
1688 sq = virtnet_xdp_get_sq(vi);
1689 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1690 u64_stats_update_begin(&sq->stats.syncp);
1691 sq->stats.kicks++;
1692 u64_stats_update_end(&sq->stats.syncp);
1693 }
1694 virtnet_xdp_put_sq(vi, sq);
1695 }
1696
1697 return received;
1698}
1699
1700static int virtnet_open(struct net_device *dev)
1701{
1702 struct virtnet_info *vi = netdev_priv(dev);
1703 int i, err;
1704
1705 enable_delayed_refill(vi);
1706
1707 for (i = 0; i < vi->max_queue_pairs; i++) {
1708 if (i < vi->curr_queue_pairs)
1709 /* Make sure we have some buffers: if oom use wq. */
1710 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1711 schedule_delayed_work(&vi->refill, 0);
1712
1713 err = xdp_rxq_info_reg(&vi->rq[i].xdp_rxq, dev, i, vi->rq[i].napi.napi_id);
1714 if (err < 0)
1715 return err;
1716
1717 err = xdp_rxq_info_reg_mem_model(&vi->rq[i].xdp_rxq,
1718 MEM_TYPE_PAGE_SHARED, NULL);
1719 if (err < 0) {
1720 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
1721 return err;
1722 }
1723
1724 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1725 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
1726 }
1727
1728 return 0;
1729}
1730
1731static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1732{
1733 struct send_queue *sq = container_of(napi, struct send_queue, napi);
1734 struct virtnet_info *vi = sq->vq->vdev->priv;
1735 unsigned int index = vq2txq(sq->vq);
1736 struct netdev_queue *txq;
1737 int opaque;
1738 bool done;
1739
1740 if (unlikely(is_xdp_raw_buffer_queue(vi, index))) {
1741 /* We don't need to enable cb for XDP */
1742 napi_complete_done(napi, 0);
1743 return 0;
1744 }
1745
1746 txq = netdev_get_tx_queue(vi->dev, index);
1747 __netif_tx_lock(txq, raw_smp_processor_id());
1748 virtqueue_disable_cb(sq->vq);
1749 free_old_xmit_skbs(sq, true);
1750
1751 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1752 netif_tx_wake_queue(txq);
1753
1754 opaque = virtqueue_enable_cb_prepare(sq->vq);
1755
1756 done = napi_complete_done(napi, 0);
1757
1758 if (!done)
1759 virtqueue_disable_cb(sq->vq);
1760
1761 __netif_tx_unlock(txq);
1762
1763 if (done) {
1764 if (unlikely(virtqueue_poll(sq->vq, opaque))) {
1765 if (napi_schedule_prep(napi)) {
1766 __netif_tx_lock(txq, raw_smp_processor_id());
1767 virtqueue_disable_cb(sq->vq);
1768 __netif_tx_unlock(txq);
1769 __napi_schedule(napi);
1770 }
1771 }
1772 }
1773
1774 return 0;
1775}
1776
1777static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1778{
1779 struct virtio_net_hdr_mrg_rxbuf *hdr;
1780 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1781 struct virtnet_info *vi = sq->vq->vdev->priv;
1782 int num_sg;
1783 unsigned hdr_len = vi->hdr_len;
1784 bool can_push;
1785
1786 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1787
1788 can_push = vi->any_header_sg &&
1789 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1790 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1791 /* Even if we can, don't push here yet as this would skew
1792 * csum_start offset below. */
1793 if (can_push)
1794 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1795 else
1796 hdr = skb_vnet_hdr(skb);
1797
1798 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1799 virtio_is_little_endian(vi->vdev), false,
1800 0))
1801 return -EPROTO;
1802
1803 if (vi->mergeable_rx_bufs)
1804 hdr->num_buffers = 0;
1805
1806 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1807 if (can_push) {
1808 __skb_push(skb, hdr_len);
1809 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1810 if (unlikely(num_sg < 0))
1811 return num_sg;
1812 /* Pull header back to avoid skew in tx bytes calculations. */
1813 __skb_pull(skb, hdr_len);
1814 } else {
1815 sg_set_buf(sq->sg, hdr, hdr_len);
1816 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
1817 if (unlikely(num_sg < 0))
1818 return num_sg;
1819 num_sg++;
1820 }
1821 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1822}
1823
1824static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1825{
1826 struct virtnet_info *vi = netdev_priv(dev);
1827 int qnum = skb_get_queue_mapping(skb);
1828 struct send_queue *sq = &vi->sq[qnum];
1829 int err;
1830 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1831 bool kick = !netdev_xmit_more();
1832 bool use_napi = sq->napi.weight;
1833
1834 /* Free up any pending old buffers before queueing new ones. */
1835 do {
1836 if (use_napi)
1837 virtqueue_disable_cb(sq->vq);
1838
1839 free_old_xmit_skbs(sq, false);
1840
1841 } while (use_napi && kick &&
1842 unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
1843
1844 /* timestamp packet in software */
1845 skb_tx_timestamp(skb);
1846
1847 /* Try to transmit */
1848 err = xmit_skb(sq, skb);
1849
1850 /* This should not happen! */
1851 if (unlikely(err)) {
1852 dev->stats.tx_fifo_errors++;
1853 if (net_ratelimit())
1854 dev_warn(&dev->dev,
1855 "Unexpected TXQ (%d) queue failure: %d\n",
1856 qnum, err);
1857 dev->stats.tx_dropped++;
1858 dev_kfree_skb_any(skb);
1859 return NETDEV_TX_OK;
1860 }
1861
1862 /* Don't wait up for transmitted skbs to be freed. */
1863 if (!use_napi) {
1864 skb_orphan(skb);
1865 nf_reset_ct(skb);
1866 }
1867
1868 /* If running out of space, stop queue to avoid getting packets that we
1869 * are then unable to transmit.
1870 * An alternative would be to force queuing layer to requeue the skb by
1871 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1872 * returned in a normal path of operation: it means that driver is not
1873 * maintaining the TX queue stop/start state properly, and causes
1874 * the stack to do a non-trivial amount of useless work.
1875 * Since most packets only take 1 or 2 ring slots, stopping the queue
1876 * early means 16 slots are typically wasted.
1877 */
1878 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1879 netif_stop_subqueue(dev, qnum);
1880 if (use_napi) {
1881 if (unlikely(!virtqueue_enable_cb_delayed(sq->vq)))
1882 virtqueue_napi_schedule(&sq->napi, sq->vq);
1883 } else if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1884 /* More just got used, free them then recheck. */
1885 free_old_xmit_skbs(sq, false);
1886 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1887 netif_start_subqueue(dev, qnum);
1888 virtqueue_disable_cb(sq->vq);
1889 }
1890 }
1891 }
1892
1893 if (kick || netif_xmit_stopped(txq)) {
1894 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1895 u64_stats_update_begin(&sq->stats.syncp);
1896 sq->stats.kicks++;
1897 u64_stats_update_end(&sq->stats.syncp);
1898 }
1899 }
1900
1901 return NETDEV_TX_OK;
1902}
1903
1904static int virtnet_rx_resize(struct virtnet_info *vi,
1905 struct receive_queue *rq, u32 ring_num)
1906{
1907 bool running = netif_running(vi->dev);
1908 int err, qindex;
1909
1910 qindex = rq - vi->rq;
1911
1912 if (running)
1913 napi_disable(&rq->napi);
1914
1915 err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_free_unused_buf);
1916 if (err)
1917 netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err);
1918
1919 if (!try_fill_recv(vi, rq, GFP_KERNEL))
1920 schedule_delayed_work(&vi->refill, 0);
1921
1922 if (running)
1923 virtnet_napi_enable(rq->vq, &rq->napi);
1924 return err;
1925}
1926
1927static int virtnet_tx_resize(struct virtnet_info *vi,
1928 struct send_queue *sq, u32 ring_num)
1929{
1930 bool running = netif_running(vi->dev);
1931 struct netdev_queue *txq;
1932 int err, qindex;
1933
1934 qindex = sq - vi->sq;
1935
1936 if (running)
1937 virtnet_napi_tx_disable(&sq->napi);
1938
1939 txq = netdev_get_tx_queue(vi->dev, qindex);
1940
1941 /* 1. wait all ximt complete
1942 * 2. fix the race of netif_stop_subqueue() vs netif_start_subqueue()
1943 */
1944 __netif_tx_lock_bh(txq);
1945
1946 /* Prevent rx poll from accessing sq. */
1947 sq->reset = true;
1948
1949 /* Prevent the upper layer from trying to send packets. */
1950 netif_stop_subqueue(vi->dev, qindex);
1951
1952 __netif_tx_unlock_bh(txq);
1953
1954 err = virtqueue_resize(sq->vq, ring_num, virtnet_sq_free_unused_buf);
1955 if (err)
1956 netdev_err(vi->dev, "resize tx fail: tx queue index: %d err: %d\n", qindex, err);
1957
1958 __netif_tx_lock_bh(txq);
1959 sq->reset = false;
1960 netif_tx_wake_queue(txq);
1961 __netif_tx_unlock_bh(txq);
1962
1963 if (running)
1964 virtnet_napi_tx_enable(vi, sq->vq, &sq->napi);
1965 return err;
1966}
1967
1968/*
1969 * Send command via the control virtqueue and check status. Commands
1970 * supported by the hypervisor, as indicated by feature bits, should
1971 * never fail unless improperly formatted.
1972 */
1973static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1974 struct scatterlist *out)
1975{
1976 struct scatterlist *sgs[4], hdr, stat;
1977 unsigned out_num = 0, tmp;
1978 int ret;
1979
1980 /* Caller should know better */
1981 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1982
1983 vi->ctrl->status = ~0;
1984 vi->ctrl->hdr.class = class;
1985 vi->ctrl->hdr.cmd = cmd;
1986 /* Add header */
1987 sg_init_one(&hdr, &vi->ctrl->hdr, sizeof(vi->ctrl->hdr));
1988 sgs[out_num++] = &hdr;
1989
1990 if (out)
1991 sgs[out_num++] = out;
1992
1993 /* Add return status. */
1994 sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status));
1995 sgs[out_num] = &stat;
1996
1997 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1998 ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1999 if (ret < 0) {
2000 dev_warn(&vi->vdev->dev,
2001 "Failed to add sgs for command vq: %d\n.", ret);
2002 return false;
2003 }
2004
2005 if (unlikely(!virtqueue_kick(vi->cvq)))
2006 return vi->ctrl->status == VIRTIO_NET_OK;
2007
2008 /* Spin for a response, the kick causes an ioport write, trapping
2009 * into the hypervisor, so the request should be handled immediately.
2010 */
2011 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
2012 !virtqueue_is_broken(vi->cvq))
2013 cpu_relax();
2014
2015 return vi->ctrl->status == VIRTIO_NET_OK;
2016}
2017
2018static int virtnet_set_mac_address(struct net_device *dev, void *p)
2019{
2020 struct virtnet_info *vi = netdev_priv(dev);
2021 struct virtio_device *vdev = vi->vdev;
2022 int ret;
2023 struct sockaddr *addr;
2024 struct scatterlist sg;
2025
2026 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
2027 return -EOPNOTSUPP;
2028
2029 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
2030 if (!addr)
2031 return -ENOMEM;
2032
2033 ret = eth_prepare_mac_addr_change(dev, addr);
2034 if (ret)
2035 goto out;
2036
2037 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
2038 sg_init_one(&sg, addr->sa_data, dev->addr_len);
2039 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
2040 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
2041 dev_warn(&vdev->dev,
2042 "Failed to set mac address by vq command.\n");
2043 ret = -EINVAL;
2044 goto out;
2045 }
2046 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
2047 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
2048 unsigned int i;
2049
2050 /* Naturally, this has an atomicity problem. */
2051 for (i = 0; i < dev->addr_len; i++)
2052 virtio_cwrite8(vdev,
2053 offsetof(struct virtio_net_config, mac) +
2054 i, addr->sa_data[i]);
2055 }
2056
2057 eth_commit_mac_addr_change(dev, p);
2058 ret = 0;
2059
2060out:
2061 kfree(addr);
2062 return ret;
2063}
2064
2065static void virtnet_stats(struct net_device *dev,
2066 struct rtnl_link_stats64 *tot)
2067{
2068 struct virtnet_info *vi = netdev_priv(dev);
2069 unsigned int start;
2070 int i;
2071
2072 for (i = 0; i < vi->max_queue_pairs; i++) {
2073 u64 tpackets, tbytes, terrors, rpackets, rbytes, rdrops;
2074 struct receive_queue *rq = &vi->rq[i];
2075 struct send_queue *sq = &vi->sq[i];
2076
2077 do {
2078 start = u64_stats_fetch_begin(&sq->stats.syncp);
2079 tpackets = sq->stats.packets;
2080 tbytes = sq->stats.bytes;
2081 terrors = sq->stats.tx_timeouts;
2082 } while (u64_stats_fetch_retry(&sq->stats.syncp, start));
2083
2084 do {
2085 start = u64_stats_fetch_begin(&rq->stats.syncp);
2086 rpackets = rq->stats.packets;
2087 rbytes = rq->stats.bytes;
2088 rdrops = rq->stats.drops;
2089 } while (u64_stats_fetch_retry(&rq->stats.syncp, start));
2090
2091 tot->rx_packets += rpackets;
2092 tot->tx_packets += tpackets;
2093 tot->rx_bytes += rbytes;
2094 tot->tx_bytes += tbytes;
2095 tot->rx_dropped += rdrops;
2096 tot->tx_errors += terrors;
2097 }
2098
2099 tot->tx_dropped = dev->stats.tx_dropped;
2100 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
2101 tot->rx_length_errors = dev->stats.rx_length_errors;
2102 tot->rx_frame_errors = dev->stats.rx_frame_errors;
2103}
2104
2105static void virtnet_ack_link_announce(struct virtnet_info *vi)
2106{
2107 rtnl_lock();
2108 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
2109 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
2110 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
2111 rtnl_unlock();
2112}
2113
2114static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
2115{
2116 struct scatterlist sg;
2117 struct net_device *dev = vi->dev;
2118
2119 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
2120 return 0;
2121
2122 vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
2123 sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq));
2124
2125 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
2126 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
2127 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
2128 queue_pairs);
2129 return -EINVAL;
2130 } else {
2131 vi->curr_queue_pairs = queue_pairs;
2132 /* virtnet_open() will refill when device is going to up. */
2133 if (dev->flags & IFF_UP)
2134 schedule_delayed_work(&vi->refill, 0);
2135 }
2136
2137 return 0;
2138}
2139
2140static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
2141{
2142 int err;
2143
2144 rtnl_lock();
2145 err = _virtnet_set_queues(vi, queue_pairs);
2146 rtnl_unlock();
2147 return err;
2148}
2149
2150static int virtnet_close(struct net_device *dev)
2151{
2152 struct virtnet_info *vi = netdev_priv(dev);
2153 int i;
2154
2155 /* Make sure NAPI doesn't schedule refill work */
2156 disable_delayed_refill(vi);
2157 /* Make sure refill_work doesn't re-enable napi! */
2158 cancel_delayed_work_sync(&vi->refill);
2159
2160 for (i = 0; i < vi->max_queue_pairs; i++) {
2161 napi_disable(&vi->rq[i].napi);
2162 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
2163 virtnet_napi_tx_disable(&vi->sq[i].napi);
2164 }
2165
2166 return 0;
2167}
2168
2169static void virtnet_set_rx_mode(struct net_device *dev)
2170{
2171 struct virtnet_info *vi = netdev_priv(dev);
2172 struct scatterlist sg[2];
2173 struct virtio_net_ctrl_mac *mac_data;
2174 struct netdev_hw_addr *ha;
2175 int uc_count;
2176 int mc_count;
2177 void *buf;
2178 int i;
2179
2180 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
2181 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
2182 return;
2183
2184 vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0);
2185 vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
2186
2187 sg_init_one(sg, &vi->ctrl->promisc, sizeof(vi->ctrl->promisc));
2188
2189 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
2190 VIRTIO_NET_CTRL_RX_PROMISC, sg))
2191 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
2192 vi->ctrl->promisc ? "en" : "dis");
2193
2194 sg_init_one(sg, &vi->ctrl->allmulti, sizeof(vi->ctrl->allmulti));
2195
2196 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
2197 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
2198 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
2199 vi->ctrl->allmulti ? "en" : "dis");
2200
2201 uc_count = netdev_uc_count(dev);
2202 mc_count = netdev_mc_count(dev);
2203 /* MAC filter - use one buffer for both lists */
2204 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
2205 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
2206 mac_data = buf;
2207 if (!buf)
2208 return;
2209
2210 sg_init_table(sg, 2);
2211
2212 /* Store the unicast list and count in the front of the buffer */
2213 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
2214 i = 0;
2215 netdev_for_each_uc_addr(ha, dev)
2216 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
2217
2218 sg_set_buf(&sg[0], mac_data,
2219 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
2220
2221 /* multicast list and count fill the end */
2222 mac_data = (void *)&mac_data->macs[uc_count][0];
2223
2224 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
2225 i = 0;
2226 netdev_for_each_mc_addr(ha, dev)
2227 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
2228
2229 sg_set_buf(&sg[1], mac_data,
2230 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
2231
2232 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
2233 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
2234 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
2235
2236 kfree(buf);
2237}
2238
2239static int virtnet_vlan_rx_add_vid(struct net_device *dev,
2240 __be16 proto, u16 vid)
2241{
2242 struct virtnet_info *vi = netdev_priv(dev);
2243 struct scatterlist sg;
2244
2245 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
2246 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
2247
2248 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
2249 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
2250 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
2251 return 0;
2252}
2253
2254static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
2255 __be16 proto, u16 vid)
2256{
2257 struct virtnet_info *vi = netdev_priv(dev);
2258 struct scatterlist sg;
2259
2260 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
2261 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
2262
2263 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
2264 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
2265 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
2266 return 0;
2267}
2268
2269static void virtnet_clean_affinity(struct virtnet_info *vi)
2270{
2271 int i;
2272
2273 if (vi->affinity_hint_set) {
2274 for (i = 0; i < vi->max_queue_pairs; i++) {
2275 virtqueue_set_affinity(vi->rq[i].vq, NULL);
2276 virtqueue_set_affinity(vi->sq[i].vq, NULL);
2277 }
2278
2279 vi->affinity_hint_set = false;
2280 }
2281}
2282
2283static void virtnet_set_affinity(struct virtnet_info *vi)
2284{
2285 cpumask_var_t mask;
2286 int stragglers;
2287 int group_size;
2288 int i, j, cpu;
2289 int num_cpu;
2290 int stride;
2291
2292 if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
2293 virtnet_clean_affinity(vi);
2294 return;
2295 }
2296
2297 num_cpu = num_online_cpus();
2298 stride = max_t(int, num_cpu / vi->curr_queue_pairs, 1);
2299 stragglers = num_cpu >= vi->curr_queue_pairs ?
2300 num_cpu % vi->curr_queue_pairs :
2301 0;
2302 cpu = cpumask_first(cpu_online_mask);
2303
2304 for (i = 0; i < vi->curr_queue_pairs; i++) {
2305 group_size = stride + (i < stragglers ? 1 : 0);
2306
2307 for (j = 0; j < group_size; j++) {
2308 cpumask_set_cpu(cpu, mask);
2309 cpu = cpumask_next_wrap(cpu, cpu_online_mask,
2310 nr_cpu_ids, false);
2311 }
2312 virtqueue_set_affinity(vi->rq[i].vq, mask);
2313 virtqueue_set_affinity(vi->sq[i].vq, mask);
2314 __netif_set_xps_queue(vi->dev, cpumask_bits(mask), i, XPS_CPUS);
2315 cpumask_clear(mask);
2316 }
2317
2318 vi->affinity_hint_set = true;
2319 free_cpumask_var(mask);
2320}
2321
2322static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
2323{
2324 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
2325 node);
2326 virtnet_set_affinity(vi);
2327 return 0;
2328}
2329
2330static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
2331{
2332 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
2333 node_dead);
2334 virtnet_set_affinity(vi);
2335 return 0;
2336}
2337
2338static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
2339{
2340 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
2341 node);
2342
2343 virtnet_clean_affinity(vi);
2344 return 0;
2345}
2346
2347static enum cpuhp_state virtionet_online;
2348
2349static int virtnet_cpu_notif_add(struct virtnet_info *vi)
2350{
2351 int ret;
2352
2353 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
2354 if (ret)
2355 return ret;
2356 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2357 &vi->node_dead);
2358 if (!ret)
2359 return ret;
2360 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2361 return ret;
2362}
2363
2364static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
2365{
2366 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2367 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2368 &vi->node_dead);
2369}
2370
2371static void virtnet_get_ringparam(struct net_device *dev,
2372 struct ethtool_ringparam *ring,
2373 struct kernel_ethtool_ringparam *kernel_ring,
2374 struct netlink_ext_ack *extack)
2375{
2376 struct virtnet_info *vi = netdev_priv(dev);
2377
2378 ring->rx_max_pending = vi->rq[0].vq->num_max;
2379 ring->tx_max_pending = vi->sq[0].vq->num_max;
2380 ring->rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
2381 ring->tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
2382}
2383
2384static int virtnet_set_ringparam(struct net_device *dev,
2385 struct ethtool_ringparam *ring,
2386 struct kernel_ethtool_ringparam *kernel_ring,
2387 struct netlink_ext_ack *extack)
2388{
2389 struct virtnet_info *vi = netdev_priv(dev);
2390 u32 rx_pending, tx_pending;
2391 struct receive_queue *rq;
2392 struct send_queue *sq;
2393 int i, err;
2394
2395 if (ring->rx_mini_pending || ring->rx_jumbo_pending)
2396 return -EINVAL;
2397
2398 rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
2399 tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
2400
2401 if (ring->rx_pending == rx_pending &&
2402 ring->tx_pending == tx_pending)
2403 return 0;
2404
2405 if (ring->rx_pending > vi->rq[0].vq->num_max)
2406 return -EINVAL;
2407
2408 if (ring->tx_pending > vi->sq[0].vq->num_max)
2409 return -EINVAL;
2410
2411 for (i = 0; i < vi->max_queue_pairs; i++) {
2412 rq = vi->rq + i;
2413 sq = vi->sq + i;
2414
2415 if (ring->tx_pending != tx_pending) {
2416 err = virtnet_tx_resize(vi, sq, ring->tx_pending);
2417 if (err)
2418 return err;
2419 }
2420
2421 if (ring->rx_pending != rx_pending) {
2422 err = virtnet_rx_resize(vi, rq, ring->rx_pending);
2423 if (err)
2424 return err;
2425 }
2426 }
2427
2428 return 0;
2429}
2430
2431static bool virtnet_commit_rss_command(struct virtnet_info *vi)
2432{
2433 struct net_device *dev = vi->dev;
2434 struct scatterlist sgs[4];
2435 unsigned int sg_buf_size;
2436
2437 /* prepare sgs */
2438 sg_init_table(sgs, 4);
2439
2440 sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table);
2441 sg_set_buf(&sgs[0], &vi->ctrl->rss, sg_buf_size);
2442
2443 sg_buf_size = sizeof(uint16_t) * (vi->ctrl->rss.indirection_table_mask + 1);
2444 sg_set_buf(&sgs[1], vi->ctrl->rss.indirection_table, sg_buf_size);
2445
2446 sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key)
2447 - offsetof(struct virtio_net_ctrl_rss, max_tx_vq);
2448 sg_set_buf(&sgs[2], &vi->ctrl->rss.max_tx_vq, sg_buf_size);
2449
2450 sg_buf_size = vi->rss_key_size;
2451 sg_set_buf(&sgs[3], vi->ctrl->rss.key, sg_buf_size);
2452
2453 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
2454 vi->has_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG
2455 : VIRTIO_NET_CTRL_MQ_HASH_CONFIG, sgs)) {
2456 dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n");
2457 return false;
2458 }
2459 return true;
2460}
2461
2462static void virtnet_init_default_rss(struct virtnet_info *vi)
2463{
2464 u32 indir_val = 0;
2465 int i = 0;
2466
2467 vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
2468 vi->rss_hash_types_saved = vi->rss_hash_types_supported;
2469 vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size
2470 ? vi->rss_indir_table_size - 1 : 0;
2471 vi->ctrl->rss.unclassified_queue = 0;
2472
2473 for (; i < vi->rss_indir_table_size; ++i) {
2474 indir_val = ethtool_rxfh_indir_default(i, vi->curr_queue_pairs);
2475 vi->ctrl->rss.indirection_table[i] = indir_val;
2476 }
2477
2478 vi->ctrl->rss.max_tx_vq = vi->curr_queue_pairs;
2479 vi->ctrl->rss.hash_key_length = vi->rss_key_size;
2480
2481 netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
2482}
2483
2484static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info)
2485{
2486 info->data = 0;
2487 switch (info->flow_type) {
2488 case TCP_V4_FLOW:
2489 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
2490 info->data = RXH_IP_SRC | RXH_IP_DST |
2491 RXH_L4_B_0_1 | RXH_L4_B_2_3;
2492 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
2493 info->data = RXH_IP_SRC | RXH_IP_DST;
2494 }
2495 break;
2496 case TCP_V6_FLOW:
2497 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
2498 info->data = RXH_IP_SRC | RXH_IP_DST |
2499 RXH_L4_B_0_1 | RXH_L4_B_2_3;
2500 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
2501 info->data = RXH_IP_SRC | RXH_IP_DST;
2502 }
2503 break;
2504 case UDP_V4_FLOW:
2505 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
2506 info->data = RXH_IP_SRC | RXH_IP_DST |
2507 RXH_L4_B_0_1 | RXH_L4_B_2_3;
2508 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
2509 info->data = RXH_IP_SRC | RXH_IP_DST;
2510 }
2511 break;
2512 case UDP_V6_FLOW:
2513 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
2514 info->data = RXH_IP_SRC | RXH_IP_DST |
2515 RXH_L4_B_0_1 | RXH_L4_B_2_3;
2516 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
2517 info->data = RXH_IP_SRC | RXH_IP_DST;
2518 }
2519 break;
2520 case IPV4_FLOW:
2521 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
2522 info->data = RXH_IP_SRC | RXH_IP_DST;
2523
2524 break;
2525 case IPV6_FLOW:
2526 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6)
2527 info->data = RXH_IP_SRC | RXH_IP_DST;
2528
2529 break;
2530 default:
2531 info->data = 0;
2532 break;
2533 }
2534}
2535
2536static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info)
2537{
2538 u32 new_hashtypes = vi->rss_hash_types_saved;
2539 bool is_disable = info->data & RXH_DISCARD;
2540 bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3);
2541
2542 /* supports only 'sd', 'sdfn' and 'r' */
2543 if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable))
2544 return false;
2545
2546 switch (info->flow_type) {
2547 case TCP_V4_FLOW:
2548 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4);
2549 if (!is_disable)
2550 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
2551 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0);
2552 break;
2553 case UDP_V4_FLOW:
2554 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4);
2555 if (!is_disable)
2556 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
2557 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0);
2558 break;
2559 case IPV4_FLOW:
2560 new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
2561 if (!is_disable)
2562 new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4;
2563 break;
2564 case TCP_V6_FLOW:
2565 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6);
2566 if (!is_disable)
2567 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
2568 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0);
2569 break;
2570 case UDP_V6_FLOW:
2571 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
2572 if (!is_disable)
2573 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
2574 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0);
2575 break;
2576 case IPV6_FLOW:
2577 new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
2578 if (!is_disable)
2579 new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6;
2580 break;
2581 default:
2582 /* unsupported flow */
2583 return false;
2584 }
2585
2586 /* if unsupported hashtype was set */
2587 if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported))
2588 return false;
2589
2590 if (new_hashtypes != vi->rss_hash_types_saved) {
2591 vi->rss_hash_types_saved = new_hashtypes;
2592 vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
2593 if (vi->dev->features & NETIF_F_RXHASH)
2594 return virtnet_commit_rss_command(vi);
2595 }
2596
2597 return true;
2598}
2599
2600static void virtnet_get_drvinfo(struct net_device *dev,
2601 struct ethtool_drvinfo *info)
2602{
2603 struct virtnet_info *vi = netdev_priv(dev);
2604 struct virtio_device *vdev = vi->vdev;
2605
2606 strscpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
2607 strscpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
2608 strscpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
2609
2610}
2611
2612/* TODO: Eliminate OOO packets during switching */
2613static int virtnet_set_channels(struct net_device *dev,
2614 struct ethtool_channels *channels)
2615{
2616 struct virtnet_info *vi = netdev_priv(dev);
2617 u16 queue_pairs = channels->combined_count;
2618 int err;
2619
2620 /* We don't support separate rx/tx channels.
2621 * We don't allow setting 'other' channels.
2622 */
2623 if (channels->rx_count || channels->tx_count || channels->other_count)
2624 return -EINVAL;
2625
2626 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
2627 return -EINVAL;
2628
2629 /* For now we don't support modifying channels while XDP is loaded
2630 * also when XDP is loaded all RX queues have XDP programs so we only
2631 * need to check a single RX queue.
2632 */
2633 if (vi->rq[0].xdp_prog)
2634 return -EINVAL;
2635
2636 cpus_read_lock();
2637 err = _virtnet_set_queues(vi, queue_pairs);
2638 if (err) {
2639 cpus_read_unlock();
2640 goto err;
2641 }
2642 virtnet_set_affinity(vi);
2643 cpus_read_unlock();
2644
2645 netif_set_real_num_tx_queues(dev, queue_pairs);
2646 netif_set_real_num_rx_queues(dev, queue_pairs);
2647 err:
2648 return err;
2649}
2650
2651static void virtnet_get_strings(struct net_device *dev, u32 stringset, u8 *data)
2652{
2653 struct virtnet_info *vi = netdev_priv(dev);
2654 unsigned int i, j;
2655 u8 *p = data;
2656
2657 switch (stringset) {
2658 case ETH_SS_STATS:
2659 for (i = 0; i < vi->curr_queue_pairs; i++) {
2660 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++)
2661 ethtool_sprintf(&p, "rx_queue_%u_%s", i,
2662 virtnet_rq_stats_desc[j].desc);
2663 }
2664
2665 for (i = 0; i < vi->curr_queue_pairs; i++) {
2666 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++)
2667 ethtool_sprintf(&p, "tx_queue_%u_%s", i,
2668 virtnet_sq_stats_desc[j].desc);
2669 }
2670 break;
2671 }
2672}
2673
2674static int virtnet_get_sset_count(struct net_device *dev, int sset)
2675{
2676 struct virtnet_info *vi = netdev_priv(dev);
2677
2678 switch (sset) {
2679 case ETH_SS_STATS:
2680 return vi->curr_queue_pairs * (VIRTNET_RQ_STATS_LEN +
2681 VIRTNET_SQ_STATS_LEN);
2682 default:
2683 return -EOPNOTSUPP;
2684 }
2685}
2686
2687static void virtnet_get_ethtool_stats(struct net_device *dev,
2688 struct ethtool_stats *stats, u64 *data)
2689{
2690 struct virtnet_info *vi = netdev_priv(dev);
2691 unsigned int idx = 0, start, i, j;
2692 const u8 *stats_base;
2693 size_t offset;
2694
2695 for (i = 0; i < vi->curr_queue_pairs; i++) {
2696 struct receive_queue *rq = &vi->rq[i];
2697
2698 stats_base = (u8 *)&rq->stats;
2699 do {
2700 start = u64_stats_fetch_begin(&rq->stats.syncp);
2701 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2702 offset = virtnet_rq_stats_desc[j].offset;
2703 data[idx + j] = *(u64 *)(stats_base + offset);
2704 }
2705 } while (u64_stats_fetch_retry(&rq->stats.syncp, start));
2706 idx += VIRTNET_RQ_STATS_LEN;
2707 }
2708
2709 for (i = 0; i < vi->curr_queue_pairs; i++) {
2710 struct send_queue *sq = &vi->sq[i];
2711
2712 stats_base = (u8 *)&sq->stats;
2713 do {
2714 start = u64_stats_fetch_begin(&sq->stats.syncp);
2715 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2716 offset = virtnet_sq_stats_desc[j].offset;
2717 data[idx + j] = *(u64 *)(stats_base + offset);
2718 }
2719 } while (u64_stats_fetch_retry(&sq->stats.syncp, start));
2720 idx += VIRTNET_SQ_STATS_LEN;
2721 }
2722}
2723
2724static void virtnet_get_channels(struct net_device *dev,
2725 struct ethtool_channels *channels)
2726{
2727 struct virtnet_info *vi = netdev_priv(dev);
2728
2729 channels->combined_count = vi->curr_queue_pairs;
2730 channels->max_combined = vi->max_queue_pairs;
2731 channels->max_other = 0;
2732 channels->rx_count = 0;
2733 channels->tx_count = 0;
2734 channels->other_count = 0;
2735}
2736
2737static int virtnet_set_link_ksettings(struct net_device *dev,
2738 const struct ethtool_link_ksettings *cmd)
2739{
2740 struct virtnet_info *vi = netdev_priv(dev);
2741
2742 return ethtool_virtdev_set_link_ksettings(dev, cmd,
2743 &vi->speed, &vi->duplex);
2744}
2745
2746static int virtnet_get_link_ksettings(struct net_device *dev,
2747 struct ethtool_link_ksettings *cmd)
2748{
2749 struct virtnet_info *vi = netdev_priv(dev);
2750
2751 cmd->base.speed = vi->speed;
2752 cmd->base.duplex = vi->duplex;
2753 cmd->base.port = PORT_OTHER;
2754
2755 return 0;
2756}
2757
2758static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi,
2759 struct ethtool_coalesce *ec)
2760{
2761 struct scatterlist sgs_tx, sgs_rx;
2762 struct virtio_net_ctrl_coal_tx coal_tx;
2763 struct virtio_net_ctrl_coal_rx coal_rx;
2764
2765 coal_tx.tx_usecs = cpu_to_le32(ec->tx_coalesce_usecs);
2766 coal_tx.tx_max_packets = cpu_to_le32(ec->tx_max_coalesced_frames);
2767 sg_init_one(&sgs_tx, &coal_tx, sizeof(coal_tx));
2768
2769 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
2770 VIRTIO_NET_CTRL_NOTF_COAL_TX_SET,
2771 &sgs_tx))
2772 return -EINVAL;
2773
2774 /* Save parameters */
2775 vi->tx_usecs = ec->tx_coalesce_usecs;
2776 vi->tx_max_packets = ec->tx_max_coalesced_frames;
2777
2778 coal_rx.rx_usecs = cpu_to_le32(ec->rx_coalesce_usecs);
2779 coal_rx.rx_max_packets = cpu_to_le32(ec->rx_max_coalesced_frames);
2780 sg_init_one(&sgs_rx, &coal_rx, sizeof(coal_rx));
2781
2782 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
2783 VIRTIO_NET_CTRL_NOTF_COAL_RX_SET,
2784 &sgs_rx))
2785 return -EINVAL;
2786
2787 /* Save parameters */
2788 vi->rx_usecs = ec->rx_coalesce_usecs;
2789 vi->rx_max_packets = ec->rx_max_coalesced_frames;
2790
2791 return 0;
2792}
2793
2794static int virtnet_coal_params_supported(struct ethtool_coalesce *ec)
2795{
2796 /* usecs coalescing is supported only if VIRTIO_NET_F_NOTF_COAL
2797 * feature is negotiated.
2798 */
2799 if (ec->rx_coalesce_usecs || ec->tx_coalesce_usecs)
2800 return -EOPNOTSUPP;
2801
2802 if (ec->tx_max_coalesced_frames > 1 ||
2803 ec->rx_max_coalesced_frames != 1)
2804 return -EINVAL;
2805
2806 return 0;
2807}
2808
2809static int virtnet_set_coalesce(struct net_device *dev,
2810 struct ethtool_coalesce *ec,
2811 struct kernel_ethtool_coalesce *kernel_coal,
2812 struct netlink_ext_ack *extack)
2813{
2814 struct virtnet_info *vi = netdev_priv(dev);
2815 int ret, i, napi_weight;
2816 bool update_napi = false;
2817
2818 /* Can't change NAPI weight if the link is up */
2819 napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
2820 if (napi_weight ^ vi->sq[0].napi.weight) {
2821 if (dev->flags & IFF_UP)
2822 return -EBUSY;
2823 else
2824 update_napi = true;
2825 }
2826
2827 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL))
2828 ret = virtnet_send_notf_coal_cmds(vi, ec);
2829 else
2830 ret = virtnet_coal_params_supported(ec);
2831
2832 if (ret)
2833 return ret;
2834
2835 if (update_napi) {
2836 for (i = 0; i < vi->max_queue_pairs; i++)
2837 vi->sq[i].napi.weight = napi_weight;
2838 }
2839
2840 return ret;
2841}
2842
2843static int virtnet_get_coalesce(struct net_device *dev,
2844 struct ethtool_coalesce *ec,
2845 struct kernel_ethtool_coalesce *kernel_coal,
2846 struct netlink_ext_ack *extack)
2847{
2848 struct virtnet_info *vi = netdev_priv(dev);
2849
2850 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
2851 ec->rx_coalesce_usecs = vi->rx_usecs;
2852 ec->tx_coalesce_usecs = vi->tx_usecs;
2853 ec->tx_max_coalesced_frames = vi->tx_max_packets;
2854 ec->rx_max_coalesced_frames = vi->rx_max_packets;
2855 } else {
2856 ec->rx_max_coalesced_frames = 1;
2857
2858 if (vi->sq[0].napi.weight)
2859 ec->tx_max_coalesced_frames = 1;
2860 }
2861
2862 return 0;
2863}
2864
2865static void virtnet_init_settings(struct net_device *dev)
2866{
2867 struct virtnet_info *vi = netdev_priv(dev);
2868
2869 vi->speed = SPEED_UNKNOWN;
2870 vi->duplex = DUPLEX_UNKNOWN;
2871}
2872
2873static void virtnet_update_settings(struct virtnet_info *vi)
2874{
2875 u32 speed;
2876 u8 duplex;
2877
2878 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
2879 return;
2880
2881 virtio_cread_le(vi->vdev, struct virtio_net_config, speed, &speed);
2882
2883 if (ethtool_validate_speed(speed))
2884 vi->speed = speed;
2885
2886 virtio_cread_le(vi->vdev, struct virtio_net_config, duplex, &duplex);
2887
2888 if (ethtool_validate_duplex(duplex))
2889 vi->duplex = duplex;
2890}
2891
2892static u32 virtnet_get_rxfh_key_size(struct net_device *dev)
2893{
2894 return ((struct virtnet_info *)netdev_priv(dev))->rss_key_size;
2895}
2896
2897static u32 virtnet_get_rxfh_indir_size(struct net_device *dev)
2898{
2899 return ((struct virtnet_info *)netdev_priv(dev))->rss_indir_table_size;
2900}
2901
2902static int virtnet_get_rxfh(struct net_device *dev, u32 *indir, u8 *key, u8 *hfunc)
2903{
2904 struct virtnet_info *vi = netdev_priv(dev);
2905 int i;
2906
2907 if (indir) {
2908 for (i = 0; i < vi->rss_indir_table_size; ++i)
2909 indir[i] = vi->ctrl->rss.indirection_table[i];
2910 }
2911
2912 if (key)
2913 memcpy(key, vi->ctrl->rss.key, vi->rss_key_size);
2914
2915 if (hfunc)
2916 *hfunc = ETH_RSS_HASH_TOP;
2917
2918 return 0;
2919}
2920
2921static int virtnet_set_rxfh(struct net_device *dev, const u32 *indir, const u8 *key, const u8 hfunc)
2922{
2923 struct virtnet_info *vi = netdev_priv(dev);
2924 int i;
2925
2926 if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
2927 return -EOPNOTSUPP;
2928
2929 if (indir) {
2930 for (i = 0; i < vi->rss_indir_table_size; ++i)
2931 vi->ctrl->rss.indirection_table[i] = indir[i];
2932 }
2933 if (key)
2934 memcpy(vi->ctrl->rss.key, key, vi->rss_key_size);
2935
2936 virtnet_commit_rss_command(vi);
2937
2938 return 0;
2939}
2940
2941static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info, u32 *rule_locs)
2942{
2943 struct virtnet_info *vi = netdev_priv(dev);
2944 int rc = 0;
2945
2946 switch (info->cmd) {
2947 case ETHTOOL_GRXRINGS:
2948 info->data = vi->curr_queue_pairs;
2949 break;
2950 case ETHTOOL_GRXFH:
2951 virtnet_get_hashflow(vi, info);
2952 break;
2953 default:
2954 rc = -EOPNOTSUPP;
2955 }
2956
2957 return rc;
2958}
2959
2960static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
2961{
2962 struct virtnet_info *vi = netdev_priv(dev);
2963 int rc = 0;
2964
2965 switch (info->cmd) {
2966 case ETHTOOL_SRXFH:
2967 if (!virtnet_set_hashflow(vi, info))
2968 rc = -EINVAL;
2969
2970 break;
2971 default:
2972 rc = -EOPNOTSUPP;
2973 }
2974
2975 return rc;
2976}
2977
2978static const struct ethtool_ops virtnet_ethtool_ops = {
2979 .supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES |
2980 ETHTOOL_COALESCE_USECS,
2981 .get_drvinfo = virtnet_get_drvinfo,
2982 .get_link = ethtool_op_get_link,
2983 .get_ringparam = virtnet_get_ringparam,
2984 .set_ringparam = virtnet_set_ringparam,
2985 .get_strings = virtnet_get_strings,
2986 .get_sset_count = virtnet_get_sset_count,
2987 .get_ethtool_stats = virtnet_get_ethtool_stats,
2988 .set_channels = virtnet_set_channels,
2989 .get_channels = virtnet_get_channels,
2990 .get_ts_info = ethtool_op_get_ts_info,
2991 .get_link_ksettings = virtnet_get_link_ksettings,
2992 .set_link_ksettings = virtnet_set_link_ksettings,
2993 .set_coalesce = virtnet_set_coalesce,
2994 .get_coalesce = virtnet_get_coalesce,
2995 .get_rxfh_key_size = virtnet_get_rxfh_key_size,
2996 .get_rxfh_indir_size = virtnet_get_rxfh_indir_size,
2997 .get_rxfh = virtnet_get_rxfh,
2998 .set_rxfh = virtnet_set_rxfh,
2999 .get_rxnfc = virtnet_get_rxnfc,
3000 .set_rxnfc = virtnet_set_rxnfc,
3001};
3002
3003static void virtnet_freeze_down(struct virtio_device *vdev)
3004{
3005 struct virtnet_info *vi = vdev->priv;
3006
3007 /* Make sure no work handler is accessing the device */
3008 flush_work(&vi->config_work);
3009
3010 netif_tx_lock_bh(vi->dev);
3011 netif_device_detach(vi->dev);
3012 netif_tx_unlock_bh(vi->dev);
3013 if (netif_running(vi->dev))
3014 virtnet_close(vi->dev);
3015}
3016
3017static int init_vqs(struct virtnet_info *vi);
3018
3019static int virtnet_restore_up(struct virtio_device *vdev)
3020{
3021 struct virtnet_info *vi = vdev->priv;
3022 int err;
3023
3024 err = init_vqs(vi);
3025 if (err)
3026 return err;
3027
3028 virtio_device_ready(vdev);
3029
3030 enable_delayed_refill(vi);
3031
3032 if (netif_running(vi->dev)) {
3033 err = virtnet_open(vi->dev);
3034 if (err)
3035 return err;
3036 }
3037
3038 netif_tx_lock_bh(vi->dev);
3039 netif_device_attach(vi->dev);
3040 netif_tx_unlock_bh(vi->dev);
3041 return err;
3042}
3043
3044static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
3045{
3046 struct scatterlist sg;
3047 vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads);
3048
3049 sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads));
3050
3051 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
3052 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
3053 dev_warn(&vi->dev->dev, "Fail to set guest offload.\n");
3054 return -EINVAL;
3055 }
3056
3057 return 0;
3058}
3059
3060static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
3061{
3062 u64 offloads = 0;
3063
3064 if (!vi->guest_offloads)
3065 return 0;
3066
3067 return virtnet_set_guest_offloads(vi, offloads);
3068}
3069
3070static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
3071{
3072 u64 offloads = vi->guest_offloads;
3073
3074 if (!vi->guest_offloads)
3075 return 0;
3076
3077 return virtnet_set_guest_offloads(vi, offloads);
3078}
3079
3080static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
3081 struct netlink_ext_ack *extack)
3082{
3083 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
3084 struct virtnet_info *vi = netdev_priv(dev);
3085 struct bpf_prog *old_prog;
3086 u16 xdp_qp = 0, curr_qp;
3087 int i, err;
3088
3089 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
3090 && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3091 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
3092 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
3093 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
3094 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM) ||
3095 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO4) ||
3096 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO6))) {
3097 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing GRO_HW/CSUM, disable GRO_HW/CSUM first");
3098 return -EOPNOTSUPP;
3099 }
3100
3101 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
3102 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
3103 return -EINVAL;
3104 }
3105
3106 if (dev->mtu > max_sz) {
3107 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
3108 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
3109 return -EINVAL;
3110 }
3111
3112 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
3113 if (prog)
3114 xdp_qp = nr_cpu_ids;
3115
3116 /* XDP requires extra queues for XDP_TX */
3117 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
3118 netdev_warn_once(dev, "XDP request %i queues but max is %i. XDP_TX and XDP_REDIRECT will operate in a slower locked tx mode.\n",
3119 curr_qp + xdp_qp, vi->max_queue_pairs);
3120 xdp_qp = 0;
3121 }
3122
3123 old_prog = rtnl_dereference(vi->rq[0].xdp_prog);
3124 if (!prog && !old_prog)
3125 return 0;
3126
3127 if (prog)
3128 bpf_prog_add(prog, vi->max_queue_pairs - 1);
3129
3130 /* Make sure NAPI is not using any XDP TX queues for RX. */
3131 if (netif_running(dev)) {
3132 for (i = 0; i < vi->max_queue_pairs; i++) {
3133 napi_disable(&vi->rq[i].napi);
3134 virtnet_napi_tx_disable(&vi->sq[i].napi);
3135 }
3136 }
3137
3138 if (!prog) {
3139 for (i = 0; i < vi->max_queue_pairs; i++) {
3140 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
3141 if (i == 0)
3142 virtnet_restore_guest_offloads(vi);
3143 }
3144 synchronize_net();
3145 }
3146
3147 err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
3148 if (err)
3149 goto err;
3150 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
3151 vi->xdp_queue_pairs = xdp_qp;
3152
3153 if (prog) {
3154 vi->xdp_enabled = true;
3155 for (i = 0; i < vi->max_queue_pairs; i++) {
3156 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
3157 if (i == 0 && !old_prog)
3158 virtnet_clear_guest_offloads(vi);
3159 }
3160 } else {
3161 vi->xdp_enabled = false;
3162 }
3163
3164 for (i = 0; i < vi->max_queue_pairs; i++) {
3165 if (old_prog)
3166 bpf_prog_put(old_prog);
3167 if (netif_running(dev)) {
3168 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
3169 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
3170 &vi->sq[i].napi);
3171 }
3172 }
3173
3174 return 0;
3175
3176err:
3177 if (!prog) {
3178 virtnet_clear_guest_offloads(vi);
3179 for (i = 0; i < vi->max_queue_pairs; i++)
3180 rcu_assign_pointer(vi->rq[i].xdp_prog, old_prog);
3181 }
3182
3183 if (netif_running(dev)) {
3184 for (i = 0; i < vi->max_queue_pairs; i++) {
3185 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
3186 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
3187 &vi->sq[i].napi);
3188 }
3189 }
3190 if (prog)
3191 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
3192 return err;
3193}
3194
3195static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
3196{
3197 switch (xdp->command) {
3198 case XDP_SETUP_PROG:
3199 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
3200 default:
3201 return -EINVAL;
3202 }
3203}
3204
3205static int virtnet_get_phys_port_name(struct net_device *dev, char *buf,
3206 size_t len)
3207{
3208 struct virtnet_info *vi = netdev_priv(dev);
3209 int ret;
3210
3211 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
3212 return -EOPNOTSUPP;
3213
3214 ret = snprintf(buf, len, "sby");
3215 if (ret >= len)
3216 return -EOPNOTSUPP;
3217
3218 return 0;
3219}
3220
3221static int virtnet_set_features(struct net_device *dev,
3222 netdev_features_t features)
3223{
3224 struct virtnet_info *vi = netdev_priv(dev);
3225 u64 offloads;
3226 int err;
3227
3228 if ((dev->features ^ features) & NETIF_F_GRO_HW) {
3229 if (vi->xdp_enabled)
3230 return -EBUSY;
3231
3232 if (features & NETIF_F_GRO_HW)
3233 offloads = vi->guest_offloads_capable;
3234 else
3235 offloads = vi->guest_offloads_capable &
3236 ~GUEST_OFFLOAD_GRO_HW_MASK;
3237
3238 err = virtnet_set_guest_offloads(vi, offloads);
3239 if (err)
3240 return err;
3241 vi->guest_offloads = offloads;
3242 }
3243
3244 if ((dev->features ^ features) & NETIF_F_RXHASH) {
3245 if (features & NETIF_F_RXHASH)
3246 vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
3247 else
3248 vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
3249
3250 if (!virtnet_commit_rss_command(vi))
3251 return -EINVAL;
3252 }
3253
3254 return 0;
3255}
3256
3257static void virtnet_tx_timeout(struct net_device *dev, unsigned int txqueue)
3258{
3259 struct virtnet_info *priv = netdev_priv(dev);
3260 struct send_queue *sq = &priv->sq[txqueue];
3261 struct netdev_queue *txq = netdev_get_tx_queue(dev, txqueue);
3262
3263 u64_stats_update_begin(&sq->stats.syncp);
3264 sq->stats.tx_timeouts++;
3265 u64_stats_update_end(&sq->stats.syncp);
3266
3267 netdev_err(dev, "TX timeout on queue: %u, sq: %s, vq: 0x%x, name: %s, %u usecs ago\n",
3268 txqueue, sq->name, sq->vq->index, sq->vq->name,
3269 jiffies_to_usecs(jiffies - READ_ONCE(txq->trans_start)));
3270}
3271
3272static const struct net_device_ops virtnet_netdev = {
3273 .ndo_open = virtnet_open,
3274 .ndo_stop = virtnet_close,
3275 .ndo_start_xmit = start_xmit,
3276 .ndo_validate_addr = eth_validate_addr,
3277 .ndo_set_mac_address = virtnet_set_mac_address,
3278 .ndo_set_rx_mode = virtnet_set_rx_mode,
3279 .ndo_get_stats64 = virtnet_stats,
3280 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
3281 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
3282 .ndo_bpf = virtnet_xdp,
3283 .ndo_xdp_xmit = virtnet_xdp_xmit,
3284 .ndo_features_check = passthru_features_check,
3285 .ndo_get_phys_port_name = virtnet_get_phys_port_name,
3286 .ndo_set_features = virtnet_set_features,
3287 .ndo_tx_timeout = virtnet_tx_timeout,
3288};
3289
3290static void virtnet_config_changed_work(struct work_struct *work)
3291{
3292 struct virtnet_info *vi =
3293 container_of(work, struct virtnet_info, config_work);
3294 u16 v;
3295
3296 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
3297 struct virtio_net_config, status, &v) < 0)
3298 return;
3299
3300 if (v & VIRTIO_NET_S_ANNOUNCE) {
3301 netdev_notify_peers(vi->dev);
3302 virtnet_ack_link_announce(vi);
3303 }
3304
3305 /* Ignore unknown (future) status bits */
3306 v &= VIRTIO_NET_S_LINK_UP;
3307
3308 if (vi->status == v)
3309 return;
3310
3311 vi->status = v;
3312
3313 if (vi->status & VIRTIO_NET_S_LINK_UP) {
3314 virtnet_update_settings(vi);
3315 netif_carrier_on(vi->dev);
3316 netif_tx_wake_all_queues(vi->dev);
3317 } else {
3318 netif_carrier_off(vi->dev);
3319 netif_tx_stop_all_queues(vi->dev);
3320 }
3321}
3322
3323static void virtnet_config_changed(struct virtio_device *vdev)
3324{
3325 struct virtnet_info *vi = vdev->priv;
3326
3327 schedule_work(&vi->config_work);
3328}
3329
3330static void virtnet_free_queues(struct virtnet_info *vi)
3331{
3332 int i;
3333
3334 for (i = 0; i < vi->max_queue_pairs; i++) {
3335 __netif_napi_del(&vi->rq[i].napi);
3336 __netif_napi_del(&vi->sq[i].napi);
3337 }
3338
3339 /* We called __netif_napi_del(),
3340 * we need to respect an RCU grace period before freeing vi->rq
3341 */
3342 synchronize_net();
3343
3344 kfree(vi->rq);
3345 kfree(vi->sq);
3346 kfree(vi->ctrl);
3347}
3348
3349static void _free_receive_bufs(struct virtnet_info *vi)
3350{
3351 struct bpf_prog *old_prog;
3352 int i;
3353
3354 for (i = 0; i < vi->max_queue_pairs; i++) {
3355 while (vi->rq[i].pages)
3356 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
3357
3358 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
3359 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
3360 if (old_prog)
3361 bpf_prog_put(old_prog);
3362 }
3363}
3364
3365static void free_receive_bufs(struct virtnet_info *vi)
3366{
3367 rtnl_lock();
3368 _free_receive_bufs(vi);
3369 rtnl_unlock();
3370}
3371
3372static void free_receive_page_frags(struct virtnet_info *vi)
3373{
3374 int i;
3375 for (i = 0; i < vi->max_queue_pairs; i++)
3376 if (vi->rq[i].alloc_frag.page)
3377 put_page(vi->rq[i].alloc_frag.page);
3378}
3379
3380static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf)
3381{
3382 if (!is_xdp_frame(buf))
3383 dev_kfree_skb(buf);
3384 else
3385 xdp_return_frame(ptr_to_xdp(buf));
3386}
3387
3388static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf)
3389{
3390 struct virtnet_info *vi = vq->vdev->priv;
3391 int i = vq2rxq(vq);
3392
3393 if (vi->mergeable_rx_bufs)
3394 put_page(virt_to_head_page(buf));
3395 else if (vi->big_packets)
3396 give_pages(&vi->rq[i], buf);
3397 else
3398 put_page(virt_to_head_page(buf));
3399}
3400
3401static void free_unused_bufs(struct virtnet_info *vi)
3402{
3403 void *buf;
3404 int i;
3405
3406 for (i = 0; i < vi->max_queue_pairs; i++) {
3407 struct virtqueue *vq = vi->sq[i].vq;
3408 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
3409 virtnet_sq_free_unused_buf(vq, buf);
3410 }
3411
3412 for (i = 0; i < vi->max_queue_pairs; i++) {
3413 struct virtqueue *vq = vi->rq[i].vq;
3414 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
3415 virtnet_rq_free_unused_buf(vq, buf);
3416 }
3417}
3418
3419static void virtnet_del_vqs(struct virtnet_info *vi)
3420{
3421 struct virtio_device *vdev = vi->vdev;
3422
3423 virtnet_clean_affinity(vi);
3424
3425 vdev->config->del_vqs(vdev);
3426
3427 virtnet_free_queues(vi);
3428}
3429
3430/* How large should a single buffer be so a queue full of these can fit at
3431 * least one full packet?
3432 * Logic below assumes the mergeable buffer header is used.
3433 */
3434static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
3435{
3436 const unsigned int hdr_len = vi->hdr_len;
3437 unsigned int rq_size = virtqueue_get_vring_size(vq);
3438 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
3439 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
3440 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
3441
3442 return max(max(min_buf_len, hdr_len) - hdr_len,
3443 (unsigned int)GOOD_PACKET_LEN);
3444}
3445
3446static int virtnet_find_vqs(struct virtnet_info *vi)
3447{
3448 vq_callback_t **callbacks;
3449 struct virtqueue **vqs;
3450 int ret = -ENOMEM;
3451 int i, total_vqs;
3452 const char **names;
3453 bool *ctx;
3454
3455 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
3456 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
3457 * possible control vq.
3458 */
3459 total_vqs = vi->max_queue_pairs * 2 +
3460 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
3461
3462 /* Allocate space for find_vqs parameters */
3463 vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
3464 if (!vqs)
3465 goto err_vq;
3466 callbacks = kmalloc_array(total_vqs, sizeof(*callbacks), GFP_KERNEL);
3467 if (!callbacks)
3468 goto err_callback;
3469 names = kmalloc_array(total_vqs, sizeof(*names), GFP_KERNEL);
3470 if (!names)
3471 goto err_names;
3472 if (!vi->big_packets || vi->mergeable_rx_bufs) {
3473 ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL);
3474 if (!ctx)
3475 goto err_ctx;
3476 } else {
3477 ctx = NULL;
3478 }
3479
3480 /* Parameters for control virtqueue, if any */
3481 if (vi->has_cvq) {
3482 callbacks[total_vqs - 1] = NULL;
3483 names[total_vqs - 1] = "control";
3484 }
3485
3486 /* Allocate/initialize parameters for send/receive virtqueues */
3487 for (i = 0; i < vi->max_queue_pairs; i++) {
3488 callbacks[rxq2vq(i)] = skb_recv_done;
3489 callbacks[txq2vq(i)] = skb_xmit_done;
3490 sprintf(vi->rq[i].name, "input.%d", i);
3491 sprintf(vi->sq[i].name, "output.%d", i);
3492 names[rxq2vq(i)] = vi->rq[i].name;
3493 names[txq2vq(i)] = vi->sq[i].name;
3494 if (ctx)
3495 ctx[rxq2vq(i)] = true;
3496 }
3497
3498 ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks,
3499 names, ctx, NULL);
3500 if (ret)
3501 goto err_find;
3502
3503 if (vi->has_cvq) {
3504 vi->cvq = vqs[total_vqs - 1];
3505 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
3506 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
3507 }
3508
3509 for (i = 0; i < vi->max_queue_pairs; i++) {
3510 vi->rq[i].vq = vqs[rxq2vq(i)];
3511 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
3512 vi->sq[i].vq = vqs[txq2vq(i)];
3513 }
3514
3515 /* run here: ret == 0. */
3516
3517
3518err_find:
3519 kfree(ctx);
3520err_ctx:
3521 kfree(names);
3522err_names:
3523 kfree(callbacks);
3524err_callback:
3525 kfree(vqs);
3526err_vq:
3527 return ret;
3528}
3529
3530static int virtnet_alloc_queues(struct virtnet_info *vi)
3531{
3532 int i;
3533
3534 if (vi->has_cvq) {
3535 vi->ctrl = kzalloc(sizeof(*vi->ctrl), GFP_KERNEL);
3536 if (!vi->ctrl)
3537 goto err_ctrl;
3538 } else {
3539 vi->ctrl = NULL;
3540 }
3541 vi->sq = kcalloc(vi->max_queue_pairs, sizeof(*vi->sq), GFP_KERNEL);
3542 if (!vi->sq)
3543 goto err_sq;
3544 vi->rq = kcalloc(vi->max_queue_pairs, sizeof(*vi->rq), GFP_KERNEL);
3545 if (!vi->rq)
3546 goto err_rq;
3547
3548 INIT_DELAYED_WORK(&vi->refill, refill_work);
3549 for (i = 0; i < vi->max_queue_pairs; i++) {
3550 vi->rq[i].pages = NULL;
3551 netif_napi_add_weight(vi->dev, &vi->rq[i].napi, virtnet_poll,
3552 napi_weight);
3553 netif_napi_add_tx_weight(vi->dev, &vi->sq[i].napi,
3554 virtnet_poll_tx,
3555 napi_tx ? napi_weight : 0);
3556
3557 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
3558 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
3559 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
3560
3561 u64_stats_init(&vi->rq[i].stats.syncp);
3562 u64_stats_init(&vi->sq[i].stats.syncp);
3563 }
3564
3565 return 0;
3566
3567err_rq:
3568 kfree(vi->sq);
3569err_sq:
3570 kfree(vi->ctrl);
3571err_ctrl:
3572 return -ENOMEM;
3573}
3574
3575static int init_vqs(struct virtnet_info *vi)
3576{
3577 int ret;
3578
3579 /* Allocate send & receive queues */
3580 ret = virtnet_alloc_queues(vi);
3581 if (ret)
3582 goto err;
3583
3584 ret = virtnet_find_vqs(vi);
3585 if (ret)
3586 goto err_free;
3587
3588 cpus_read_lock();
3589 virtnet_set_affinity(vi);
3590 cpus_read_unlock();
3591
3592 return 0;
3593
3594err_free:
3595 virtnet_free_queues(vi);
3596err:
3597 return ret;
3598}
3599
3600#ifdef CONFIG_SYSFS
3601static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
3602 char *buf)
3603{
3604 struct virtnet_info *vi = netdev_priv(queue->dev);
3605 unsigned int queue_index = get_netdev_rx_queue_index(queue);
3606 unsigned int headroom = virtnet_get_headroom(vi);
3607 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
3608 struct ewma_pkt_len *avg;
3609
3610 BUG_ON(queue_index >= vi->max_queue_pairs);
3611 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
3612 return sprintf(buf, "%u\n",
3613 get_mergeable_buf_len(&vi->rq[queue_index], avg,
3614 SKB_DATA_ALIGN(headroom + tailroom)));
3615}
3616
3617static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
3618 __ATTR_RO(mergeable_rx_buffer_size);
3619
3620static struct attribute *virtio_net_mrg_rx_attrs[] = {
3621 &mergeable_rx_buffer_size_attribute.attr,
3622 NULL
3623};
3624
3625static const struct attribute_group virtio_net_mrg_rx_group = {
3626 .name = "virtio_net",
3627 .attrs = virtio_net_mrg_rx_attrs
3628};
3629#endif
3630
3631static bool virtnet_fail_on_feature(struct virtio_device *vdev,
3632 unsigned int fbit,
3633 const char *fname, const char *dname)
3634{
3635 if (!virtio_has_feature(vdev, fbit))
3636 return false;
3637
3638 dev_err(&vdev->dev, "device advertises feature %s but not %s",
3639 fname, dname);
3640
3641 return true;
3642}
3643
3644#define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
3645 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
3646
3647static bool virtnet_validate_features(struct virtio_device *vdev)
3648{
3649 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
3650 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
3651 "VIRTIO_NET_F_CTRL_VQ") ||
3652 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
3653 "VIRTIO_NET_F_CTRL_VQ") ||
3654 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
3655 "VIRTIO_NET_F_CTRL_VQ") ||
3656 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
3657 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
3658 "VIRTIO_NET_F_CTRL_VQ") ||
3659 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS,
3660 "VIRTIO_NET_F_CTRL_VQ") ||
3661 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
3662 "VIRTIO_NET_F_CTRL_VQ") ||
3663 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_NOTF_COAL,
3664 "VIRTIO_NET_F_CTRL_VQ"))) {
3665 return false;
3666 }
3667
3668 return true;
3669}
3670
3671#define MIN_MTU ETH_MIN_MTU
3672#define MAX_MTU ETH_MAX_MTU
3673
3674static int virtnet_validate(struct virtio_device *vdev)
3675{
3676 if (!vdev->config->get) {
3677 dev_err(&vdev->dev, "%s failure: config access disabled\n",
3678 __func__);
3679 return -EINVAL;
3680 }
3681
3682 if (!virtnet_validate_features(vdev))
3683 return -EINVAL;
3684
3685 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
3686 int mtu = virtio_cread16(vdev,
3687 offsetof(struct virtio_net_config,
3688 mtu));
3689 if (mtu < MIN_MTU)
3690 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
3691 }
3692
3693 return 0;
3694}
3695
3696static bool virtnet_check_guest_gso(const struct virtnet_info *vi)
3697{
3698 return virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3699 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
3700 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
3701 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
3702 (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO4) &&
3703 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO6));
3704}
3705
3706static void virtnet_set_big_packets(struct virtnet_info *vi, const int mtu)
3707{
3708 bool guest_gso = virtnet_check_guest_gso(vi);
3709
3710 /* If device can receive ANY guest GSO packets, regardless of mtu,
3711 * allocate packets of maximum size, otherwise limit it to only
3712 * mtu size worth only.
3713 */
3714 if (mtu > ETH_DATA_LEN || guest_gso) {
3715 vi->big_packets = true;
3716 vi->big_packets_num_skbfrags = guest_gso ? MAX_SKB_FRAGS : DIV_ROUND_UP(mtu, PAGE_SIZE);
3717 }
3718}
3719
3720static int virtnet_probe(struct virtio_device *vdev)
3721{
3722 int i, err = -ENOMEM;
3723 struct net_device *dev;
3724 struct virtnet_info *vi;
3725 u16 max_queue_pairs;
3726 int mtu = 0;
3727
3728 /* Find if host supports multiqueue/rss virtio_net device */
3729 max_queue_pairs = 1;
3730 if (virtio_has_feature(vdev, VIRTIO_NET_F_MQ) || virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
3731 max_queue_pairs =
3732 virtio_cread16(vdev, offsetof(struct virtio_net_config, max_virtqueue_pairs));
3733
3734 /* We need at least 2 queue's */
3735 if (max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
3736 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
3737 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
3738 max_queue_pairs = 1;
3739
3740 /* Allocate ourselves a network device with room for our info */
3741 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
3742 if (!dev)
3743 return -ENOMEM;
3744
3745 /* Set up network device as normal. */
3746 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE |
3747 IFF_TX_SKB_NO_LINEAR;
3748 dev->netdev_ops = &virtnet_netdev;
3749 dev->features = NETIF_F_HIGHDMA;
3750
3751 dev->ethtool_ops = &virtnet_ethtool_ops;
3752 SET_NETDEV_DEV(dev, &vdev->dev);
3753
3754 /* Do we support "hardware" checksums? */
3755 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
3756 /* This opens up the world of extra features. */
3757 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
3758 if (csum)
3759 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
3760
3761 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
3762 dev->hw_features |= NETIF_F_TSO
3763 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
3764 }
3765 /* Individual feature bits: what can host handle? */
3766 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
3767 dev->hw_features |= NETIF_F_TSO;
3768 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
3769 dev->hw_features |= NETIF_F_TSO6;
3770 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
3771 dev->hw_features |= NETIF_F_TSO_ECN;
3772 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_USO))
3773 dev->hw_features |= NETIF_F_GSO_UDP_L4;
3774
3775 dev->features |= NETIF_F_GSO_ROBUST;
3776
3777 if (gso)
3778 dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
3779 /* (!csum && gso) case will be fixed by register_netdev() */
3780 }
3781 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
3782 dev->features |= NETIF_F_RXCSUM;
3783 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3784 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6))
3785 dev->features |= NETIF_F_GRO_HW;
3786 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS))
3787 dev->hw_features |= NETIF_F_GRO_HW;
3788
3789 dev->vlan_features = dev->features;
3790
3791 /* MTU range: 68 - 65535 */
3792 dev->min_mtu = MIN_MTU;
3793 dev->max_mtu = MAX_MTU;
3794
3795 /* Configuration may specify what MAC to use. Otherwise random. */
3796 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
3797 u8 addr[ETH_ALEN];
3798
3799 virtio_cread_bytes(vdev,
3800 offsetof(struct virtio_net_config, mac),
3801 addr, ETH_ALEN);
3802 eth_hw_addr_set(dev, addr);
3803 } else {
3804 eth_hw_addr_random(dev);
3805 }
3806
3807 /* Set up our device-specific information */
3808 vi = netdev_priv(dev);
3809 vi->dev = dev;
3810 vi->vdev = vdev;
3811 vdev->priv = vi;
3812
3813 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
3814 spin_lock_init(&vi->refill_lock);
3815
3816 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
3817 vi->mergeable_rx_bufs = true;
3818
3819 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
3820 vi->rx_usecs = 0;
3821 vi->tx_usecs = 0;
3822 vi->tx_max_packets = 0;
3823 vi->rx_max_packets = 0;
3824 }
3825
3826 if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT))
3827 vi->has_rss_hash_report = true;
3828
3829 if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
3830 vi->has_rss = true;
3831
3832 if (vi->has_rss || vi->has_rss_hash_report) {
3833 vi->rss_indir_table_size =
3834 virtio_cread16(vdev, offsetof(struct virtio_net_config,
3835 rss_max_indirection_table_length));
3836 vi->rss_key_size =
3837 virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
3838
3839 vi->rss_hash_types_supported =
3840 virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
3841 vi->rss_hash_types_supported &=
3842 ~(VIRTIO_NET_RSS_HASH_TYPE_IP_EX |
3843 VIRTIO_NET_RSS_HASH_TYPE_TCP_EX |
3844 VIRTIO_NET_RSS_HASH_TYPE_UDP_EX);
3845
3846 dev->hw_features |= NETIF_F_RXHASH;
3847 }
3848
3849 if (vi->has_rss_hash_report)
3850 vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);
3851 else if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
3852 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
3853 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
3854 else
3855 vi->hdr_len = sizeof(struct virtio_net_hdr);
3856
3857 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
3858 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
3859 vi->any_header_sg = true;
3860
3861 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
3862 vi->has_cvq = true;
3863
3864 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
3865 mtu = virtio_cread16(vdev,
3866 offsetof(struct virtio_net_config,
3867 mtu));
3868 if (mtu < dev->min_mtu) {
3869 /* Should never trigger: MTU was previously validated
3870 * in virtnet_validate.
3871 */
3872 dev_err(&vdev->dev,
3873 "device MTU appears to have changed it is now %d < %d",
3874 mtu, dev->min_mtu);
3875 err = -EINVAL;
3876 goto free;
3877 }
3878
3879 dev->mtu = mtu;
3880 dev->max_mtu = mtu;
3881 }
3882
3883 virtnet_set_big_packets(vi, mtu);
3884
3885 if (vi->any_header_sg)
3886 dev->needed_headroom = vi->hdr_len;
3887
3888 /* Enable multiqueue by default */
3889 if (num_online_cpus() >= max_queue_pairs)
3890 vi->curr_queue_pairs = max_queue_pairs;
3891 else
3892 vi->curr_queue_pairs = num_online_cpus();
3893 vi->max_queue_pairs = max_queue_pairs;
3894
3895 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
3896 err = init_vqs(vi);
3897 if (err)
3898 goto free;
3899
3900#ifdef CONFIG_SYSFS
3901 if (vi->mergeable_rx_bufs)
3902 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
3903#endif
3904 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
3905 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
3906
3907 virtnet_init_settings(dev);
3908
3909 if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
3910 vi->failover = net_failover_create(vi->dev);
3911 if (IS_ERR(vi->failover)) {
3912 err = PTR_ERR(vi->failover);
3913 goto free_vqs;
3914 }
3915 }
3916
3917 if (vi->has_rss || vi->has_rss_hash_report)
3918 virtnet_init_default_rss(vi);
3919
3920 /* serialize netdev register + virtio_device_ready() with ndo_open() */
3921 rtnl_lock();
3922
3923 err = register_netdevice(dev);
3924 if (err) {
3925 pr_debug("virtio_net: registering device failed\n");
3926 rtnl_unlock();
3927 goto free_failover;
3928 }
3929
3930 virtio_device_ready(vdev);
3931
3932 rtnl_unlock();
3933
3934 err = virtnet_cpu_notif_add(vi);
3935 if (err) {
3936 pr_debug("virtio_net: registering cpu notifier failed\n");
3937 goto free_unregister_netdev;
3938 }
3939
3940 virtnet_set_queues(vi, vi->curr_queue_pairs);
3941
3942 /* Assume link up if device can't report link status,
3943 otherwise get link status from config. */
3944 netif_carrier_off(dev);
3945 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
3946 schedule_work(&vi->config_work);
3947 } else {
3948 vi->status = VIRTIO_NET_S_LINK_UP;
3949 virtnet_update_settings(vi);
3950 netif_carrier_on(dev);
3951 }
3952
3953 for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
3954 if (virtio_has_feature(vi->vdev, guest_offloads[i]))
3955 set_bit(guest_offloads[i], &vi->guest_offloads);
3956 vi->guest_offloads_capable = vi->guest_offloads;
3957
3958 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
3959 dev->name, max_queue_pairs);
3960
3961 return 0;
3962
3963free_unregister_netdev:
3964 unregister_netdev(dev);
3965free_failover:
3966 net_failover_destroy(vi->failover);
3967free_vqs:
3968 virtio_reset_device(vdev);
3969 cancel_delayed_work_sync(&vi->refill);
3970 free_receive_page_frags(vi);
3971 virtnet_del_vqs(vi);
3972free:
3973 free_netdev(dev);
3974 return err;
3975}
3976
3977static void remove_vq_common(struct virtnet_info *vi)
3978{
3979 virtio_reset_device(vi->vdev);
3980
3981 /* Free unused buffers in both send and recv, if any. */
3982 free_unused_bufs(vi);
3983
3984 free_receive_bufs(vi);
3985
3986 free_receive_page_frags(vi);
3987
3988 virtnet_del_vqs(vi);
3989}
3990
3991static void virtnet_remove(struct virtio_device *vdev)
3992{
3993 struct virtnet_info *vi = vdev->priv;
3994
3995 virtnet_cpu_notif_remove(vi);
3996
3997 /* Make sure no work handler is accessing the device. */
3998 flush_work(&vi->config_work);
3999
4000 unregister_netdev(vi->dev);
4001
4002 net_failover_destroy(vi->failover);
4003
4004 remove_vq_common(vi);
4005
4006 free_netdev(vi->dev);
4007}
4008
4009static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
4010{
4011 struct virtnet_info *vi = vdev->priv;
4012
4013 virtnet_cpu_notif_remove(vi);
4014 virtnet_freeze_down(vdev);
4015 remove_vq_common(vi);
4016
4017 return 0;
4018}
4019
4020static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
4021{
4022 struct virtnet_info *vi = vdev->priv;
4023 int err;
4024
4025 err = virtnet_restore_up(vdev);
4026 if (err)
4027 return err;
4028 virtnet_set_queues(vi, vi->curr_queue_pairs);
4029
4030 err = virtnet_cpu_notif_add(vi);
4031 if (err) {
4032 virtnet_freeze_down(vdev);
4033 remove_vq_common(vi);
4034 return err;
4035 }
4036
4037 return 0;
4038}
4039
4040static struct virtio_device_id id_table[] = {
4041 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
4042 { 0 },
4043};
4044
4045#define VIRTNET_FEATURES \
4046 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
4047 VIRTIO_NET_F_MAC, \
4048 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
4049 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
4050 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
4051 VIRTIO_NET_F_HOST_USO, VIRTIO_NET_F_GUEST_USO4, VIRTIO_NET_F_GUEST_USO6, \
4052 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
4053 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
4054 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
4055 VIRTIO_NET_F_CTRL_MAC_ADDR, \
4056 VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
4057 VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
4058 VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT, VIRTIO_NET_F_NOTF_COAL
4059
4060static unsigned int features[] = {
4061 VIRTNET_FEATURES,
4062};
4063
4064static unsigned int features_legacy[] = {
4065 VIRTNET_FEATURES,
4066 VIRTIO_NET_F_GSO,
4067 VIRTIO_F_ANY_LAYOUT,
4068};
4069
4070static struct virtio_driver virtio_net_driver = {
4071 .feature_table = features,
4072 .feature_table_size = ARRAY_SIZE(features),
4073 .feature_table_legacy = features_legacy,
4074 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
4075 .driver.name = KBUILD_MODNAME,
4076 .driver.owner = THIS_MODULE,
4077 .id_table = id_table,
4078 .validate = virtnet_validate,
4079 .probe = virtnet_probe,
4080 .remove = virtnet_remove,
4081 .config_changed = virtnet_config_changed,
4082#ifdef CONFIG_PM_SLEEP
4083 .freeze = virtnet_freeze,
4084 .restore = virtnet_restore,
4085#endif
4086};
4087
4088static __init int virtio_net_driver_init(void)
4089{
4090 int ret;
4091
4092 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
4093 virtnet_cpu_online,
4094 virtnet_cpu_down_prep);
4095 if (ret < 0)
4096 goto out;
4097 virtionet_online = ret;
4098 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
4099 NULL, virtnet_cpu_dead);
4100 if (ret)
4101 goto err_dead;
4102 ret = register_virtio_driver(&virtio_net_driver);
4103 if (ret)
4104 goto err_virtio;
4105 return 0;
4106err_virtio:
4107 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
4108err_dead:
4109 cpuhp_remove_multi_state(virtionet_online);
4110out:
4111 return ret;
4112}
4113module_init(virtio_net_driver_init);
4114
4115static __exit void virtio_net_driver_exit(void)
4116{
4117 unregister_virtio_driver(&virtio_net_driver);
4118 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
4119 cpuhp_remove_multi_state(virtionet_online);
4120}
4121module_exit(virtio_net_driver_exit);
4122
4123MODULE_DEVICE_TABLE(virtio, id_table);
4124MODULE_DESCRIPTION("Virtio network driver");
4125MODULE_LICENSE("GPL");