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scsi: aacraid: VPD 83 type3 support
[linux/fpc-iii.git] / drivers / net / virtio_net.c
blob4a105006ca637bc985698fa378ff6d14e1494b3f
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/bpf.h>
26 #include <linux/scatterlist.h>
27 #include <linux/if_vlan.h>
28 #include <linux/slab.h>
29 #include <linux/cpu.h>
30 #include <linux/average.h>
31 #include <net/busy_poll.h>
32
33 static int napi_weight = NAPI_POLL_WEIGHT;
34 module_param(napi_weight, int, 0444);
35
36 static bool csum = true, gso = true;
37 module_param(csum, bool, 0444);
38 module_param(gso, bool, 0444);
39
40 /* FIXME: MTU in config. */
41 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
42 #define GOOD_COPY_LEN 128
43
44 /* RX packet size EWMA. The average packet size is used to determine the packet
45 * buffer size when refilling RX rings. As the entire RX ring may be refilled
46 * at once, the weight is chosen so that the EWMA will be insensitive to short-
47 * term, transient changes in packet size.
48 */
49 DECLARE_EWMA(pkt_len, 1, 64)
50
51 /* Minimum alignment for mergeable packet buffers. */
52 #define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256)
53
54 #define VIRTNET_DRIVER_VERSION "1.0.0"
55
56 struct virtnet_stats {
57 struct u64_stats_sync tx_syncp;
58 struct u64_stats_sync rx_syncp;
59 u64 tx_bytes;
60 u64 tx_packets;
61
62 u64 rx_bytes;
63 u64 rx_packets;
64 };
65
66 /* Internal representation of a send virtqueue */
67 struct send_queue {
68 /* Virtqueue associated with this send _queue */
69 struct virtqueue *vq;
70
71 /* TX: fragments + linear part + virtio header */
72 struct scatterlist sg[MAX_SKB_FRAGS + 2];
73
74 /* Name of the send queue: output.$index */
75 char name[40];
76 };
77
78 /* Internal representation of a receive virtqueue */
79 struct receive_queue {
80 /* Virtqueue associated with this receive_queue */
81 struct virtqueue *vq;
82
83 struct napi_struct napi;
84
85 struct bpf_prog __rcu *xdp_prog;
86
87 /* Chain pages by the private ptr. */
88 struct page *pages;
89
90 /* Average packet length for mergeable receive buffers. */
91 struct ewma_pkt_len mrg_avg_pkt_len;
92
93 /* Page frag for packet buffer allocation. */
94 struct page_frag alloc_frag;
95
96 /* RX: fragments + linear part + virtio header */
97 struct scatterlist sg[MAX_SKB_FRAGS + 2];
98
99 /* Name of this receive queue: input.$index */
100 char name[40];
101 };
102
103 struct virtnet_info {
104 struct virtio_device *vdev;
105 struct virtqueue *cvq;
106 struct net_device *dev;
107 struct send_queue *sq;
108 struct receive_queue *rq;
109 unsigned int status;
110
111 /* Max # of queue pairs supported by the device */
112 u16 max_queue_pairs;
113
114 /* # of queue pairs currently used by the driver */
115 u16 curr_queue_pairs;
116
117 /* # of XDP queue pairs currently used by the driver */
118 u16 xdp_queue_pairs;
119
120 /* I like... big packets and I cannot lie! */
121 bool big_packets;
122
123 /* Host will merge rx buffers for big packets (shake it! shake it!) */
124 bool mergeable_rx_bufs;
125
126 /* Has control virtqueue */
127 bool has_cvq;
128
129 /* Host can handle any s/g split between our header and packet data */
130 bool any_header_sg;
131
132 /* Packet virtio header size */
133 u8 hdr_len;
134
135 /* Active statistics */
136 struct virtnet_stats __percpu *stats;
137
138 /* Work struct for refilling if we run low on memory. */
139 struct delayed_work refill;
140
141 /* Work struct for config space updates */
142 struct work_struct config_work;
143
144 /* Does the affinity hint is set for virtqueues? */
145 bool affinity_hint_set;
146
147 /* CPU hotplug instances for online & dead */
148 struct hlist_node node;
149 struct hlist_node node_dead;
150
151 /* Control VQ buffers: protected by the rtnl lock */
152 struct virtio_net_ctrl_hdr ctrl_hdr;
153 virtio_net_ctrl_ack ctrl_status;
154 struct virtio_net_ctrl_mq ctrl_mq;
155 u8 ctrl_promisc;
156 u8 ctrl_allmulti;
157 u16 ctrl_vid;
158
159 /* Ethtool settings */
160 u8 duplex;
161 u32 speed;
162 };
163
164 struct padded_vnet_hdr {
165 struct virtio_net_hdr_mrg_rxbuf hdr;
166 /*
167 * hdr is in a separate sg buffer, and data sg buffer shares same page
168 * with this header sg. This padding makes next sg 16 byte aligned
169 * after the header.
170 */
171 char padding[4];
172 };
173
174 /* Converting between virtqueue no. and kernel tx/rx queue no.
175 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
176 */
177 static int vq2txq(struct virtqueue *vq)
178 {
179 return (vq->index - 1) / 2;
180 }
181
182 static int txq2vq(int txq)
183 {
184 return txq * 2 + 1;
185 }
186
187 static int vq2rxq(struct virtqueue *vq)
188 {
189 return vq->index / 2;
190 }
191
192 static int rxq2vq(int rxq)
193 {
194 return rxq * 2;
195 }
196
197 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
198 {
199 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
200 }
201
202 /*
203 * private is used to chain pages for big packets, put the whole
204 * most recent used list in the beginning for reuse
205 */
206 static void give_pages(struct receive_queue *rq, struct page *page)
207 {
208 struct page *end;
209
210 /* Find end of list, sew whole thing into vi->rq.pages. */
211 for (end = page; end->private; end = (struct page *)end->private);
212 end->private = (unsigned long)rq->pages;
213 rq->pages = page;
214 }
215
216 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
217 {
218 struct page *p = rq->pages;
219
220 if (p) {
221 rq->pages = (struct page *)p->private;
222 /* clear private here, it is used to chain pages */
223 p->private = 0;
224 } else
225 p = alloc_page(gfp_mask);
226 return p;
227 }
228
229 static void skb_xmit_done(struct virtqueue *vq)
230 {
231 struct virtnet_info *vi = vq->vdev->priv;
232
233 /* Suppress further interrupts. */
234 virtqueue_disable_cb(vq);
235
236 /* We were probably waiting for more output buffers. */
237 netif_wake_subqueue(vi->dev, vq2txq(vq));
238 }
239
240 static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx)
241 {
242 unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1);
243 return (truesize + 1) * MERGEABLE_BUFFER_ALIGN;
244 }
245
246 static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx)
247 {
248 return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN);
249
250 }
251
252 static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize)
253 {
254 unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN;
255 return (unsigned long)buf | (size - 1);
256 }
257
258 /* Called from bottom half context */
259 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
260 struct receive_queue *rq,
261 struct page *page, unsigned int offset,
262 unsigned int len, unsigned int truesize)
263 {
264 struct sk_buff *skb;
265 struct virtio_net_hdr_mrg_rxbuf *hdr;
266 unsigned int copy, hdr_len, hdr_padded_len;
267 char *p;
268
269 p = page_address(page) + offset;
270
271 /* copy small packet so we can reuse these pages for small data */
272 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
273 if (unlikely(!skb))
274 return NULL;
275
276 hdr = skb_vnet_hdr(skb);
277
278 hdr_len = vi->hdr_len;
279 if (vi->mergeable_rx_bufs)
280 hdr_padded_len = sizeof *hdr;
281 else
282 hdr_padded_len = sizeof(struct padded_vnet_hdr);
283
284 memcpy(hdr, p, hdr_len);
285
286 len -= hdr_len;
287 offset += hdr_padded_len;
288 p += hdr_padded_len;
289
290 copy = len;
291 if (copy > skb_tailroom(skb))
292 copy = skb_tailroom(skb);
293 memcpy(skb_put(skb, copy), p, copy);
294
295 len -= copy;
296 offset += copy;
297
298 if (vi->mergeable_rx_bufs) {
299 if (len)
300 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
301 else
302 put_page(page);
303 return skb;
304 }
305
306 /*
307 * Verify that we can indeed put this data into a skb.
308 * This is here to handle cases when the device erroneously
309 * tries to receive more than is possible. This is usually
310 * the case of a broken device.
311 */
312 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
313 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
314 dev_kfree_skb(skb);
315 return NULL;
316 }
317 BUG_ON(offset >= PAGE_SIZE);
318 while (len) {
319 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
320 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
321 frag_size, truesize);
322 len -= frag_size;
323 page = (struct page *)page->private;
324 offset = 0;
325 }
326
327 if (page)
328 give_pages(rq, page);
329
330 return skb;
331 }
332
333 static void virtnet_xdp_xmit(struct virtnet_info *vi,
334 struct receive_queue *rq,
335 struct send_queue *sq,
336 struct xdp_buff *xdp,
337 void *data)
338 {
339 struct virtio_net_hdr_mrg_rxbuf *hdr;
340 unsigned int num_sg, len;
341 void *xdp_sent;
342 int err;
343
344 /* Free up any pending old buffers before queueing new ones. */
345 while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) {
346 if (vi->mergeable_rx_bufs) {
347 struct page *sent_page = virt_to_head_page(xdp_sent);
348
349 put_page(sent_page);
350 } else { /* small buffer */
351 struct sk_buff *skb = xdp_sent;
352
353 kfree_skb(skb);
354 }
355 }
356
357 if (vi->mergeable_rx_bufs) {
358 /* Zero header and leave csum up to XDP layers */
359 hdr = xdp->data;
360 memset(hdr, 0, vi->hdr_len);
361
362 num_sg = 1;
363 sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data);
364 } else { /* small buffer */
365 struct sk_buff *skb = data;
366
367 /* Zero header and leave csum up to XDP layers */
368 hdr = skb_vnet_hdr(skb);
369 memset(hdr, 0, vi->hdr_len);
370
371 num_sg = 2;
372 sg_init_table(sq->sg, 2);
373 sg_set_buf(sq->sg, hdr, vi->hdr_len);
374 skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
375 }
376 err = virtqueue_add_outbuf(sq->vq, sq->sg, num_sg,
377 data, GFP_ATOMIC);
378 if (unlikely(err)) {
379 if (vi->mergeable_rx_bufs) {
380 struct page *page = virt_to_head_page(xdp->data);
381
382 put_page(page);
383 } else /* small buffer */
384 kfree_skb(data);
385 return; // On error abort to avoid unnecessary kick
386 }
387
388 virtqueue_kick(sq->vq);
389 }
390
391 static u32 do_xdp_prog(struct virtnet_info *vi,
392 struct receive_queue *rq,
393 struct bpf_prog *xdp_prog,
394 void *data, int len)
395 {
396 int hdr_padded_len;
397 struct xdp_buff xdp;
398 void *buf;
399 unsigned int qp;
400 u32 act;
401
402 if (vi->mergeable_rx_bufs) {
403 hdr_padded_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
404 xdp.data = data + hdr_padded_len;
405 xdp.data_end = xdp.data + (len - vi->hdr_len);
406 buf = data;
407 } else { /* small buffers */
408 struct sk_buff *skb = data;
409
410 xdp.data = skb->data;
411 xdp.data_end = xdp.data + len;
412 buf = skb->data;
413 }
414
415 act = bpf_prog_run_xdp(xdp_prog, &xdp);
416 switch (act) {
417 case XDP_PASS:
418 return XDP_PASS;
419 case XDP_TX:
420 qp = vi->curr_queue_pairs -
421 vi->xdp_queue_pairs +
422 smp_processor_id();
423 xdp.data = buf;
424 virtnet_xdp_xmit(vi, rq, &vi->sq[qp], &xdp, data);
425 return XDP_TX;
426 default:
427 bpf_warn_invalid_xdp_action(act);
428 case XDP_ABORTED:
429 case XDP_DROP:
430 return XDP_DROP;
431 }
432 }
433
434 static struct sk_buff *receive_small(struct net_device *dev,
435 struct virtnet_info *vi,
436 struct receive_queue *rq,
437 void *buf, unsigned int len)
438 {
439 struct sk_buff * skb = buf;
440 struct bpf_prog *xdp_prog;
441
442 len -= vi->hdr_len;
443 skb_trim(skb, len);
444
445 rcu_read_lock();
446 xdp_prog = rcu_dereference(rq->xdp_prog);
447 if (xdp_prog) {
448 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
449 u32 act;
450
451 if (unlikely(hdr->hdr.gso_type || hdr->hdr.flags))
452 goto err_xdp;
453 act = do_xdp_prog(vi, rq, xdp_prog, skb, len);
454 switch (act) {
455 case XDP_PASS:
456 break;
457 case XDP_TX:
458 rcu_read_unlock();
459 goto xdp_xmit;
460 case XDP_DROP:
461 default:
462 goto err_xdp;
463 }
464 }
465 rcu_read_unlock();
466
467 return skb;
468
469 err_xdp:
470 rcu_read_unlock();
471 dev->stats.rx_dropped++;
472 kfree_skb(skb);
473 xdp_xmit:
474 return NULL;
475 }
476
477 static struct sk_buff *receive_big(struct net_device *dev,
478 struct virtnet_info *vi,
479 struct receive_queue *rq,
480 void *buf,
481 unsigned int len)
482 {
483 struct page *page = buf;
484 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
485
486 if (unlikely(!skb))
487 goto err;
488
489 return skb;
490
491 err:
492 dev->stats.rx_dropped++;
493 give_pages(rq, page);
494 return NULL;
495 }
496
497 /* The conditions to enable XDP should preclude the underlying device from
498 * sending packets across multiple buffers (num_buf > 1). However per spec
499 * it does not appear to be illegal to do so but rather just against convention.
500 * So in order to avoid making a system unresponsive the packets are pushed
501 * into a page and the XDP program is run. This will be extremely slow and we
502 * push a warning to the user to fix this as soon as possible. Fixing this may
503 * require resolving the underlying hardware to determine why multiple buffers
504 * are being received or simply loading the XDP program in the ingress stack
505 * after the skb is built because there is no advantage to running it here
506 * anymore.
507 */
508 static struct page *xdp_linearize_page(struct receive_queue *rq,
509 u16 *num_buf,
510 struct page *p,
511 int offset,
512 unsigned int *len)
513 {
514 struct page *page = alloc_page(GFP_ATOMIC);
515 unsigned int page_off = 0;
516
517 if (!page)
518 return NULL;
519
520 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
521 page_off += *len;
522
523 while (--*num_buf) {
524 unsigned int buflen;
525 unsigned long ctx;
526 void *buf;
527 int off;
528
529 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &buflen);
530 if (unlikely(!ctx))
531 goto err_buf;
532
533 buf = mergeable_ctx_to_buf_address(ctx);
534 p = virt_to_head_page(buf);
535 off = buf - page_address(p);
536
537 /* guard against a misconfigured or uncooperative backend that
538 * is sending packet larger than the MTU.
539 */
540 if ((page_off + buflen) > PAGE_SIZE) {
541 put_page(p);
542 goto err_buf;
543 }
544
545 memcpy(page_address(page) + page_off,
546 page_address(p) + off, buflen);
547 page_off += buflen;
548 put_page(p);
549 }
550
551 *len = page_off;
552 return page;
553 err_buf:
554 __free_pages(page, 0);
555 return NULL;
556 }
557
558 static struct sk_buff *receive_mergeable(struct net_device *dev,
559 struct virtnet_info *vi,
560 struct receive_queue *rq,
561 unsigned long ctx,
562 unsigned int len)
563 {
564 void *buf = mergeable_ctx_to_buf_address(ctx);
565 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
566 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
567 struct page *page = virt_to_head_page(buf);
568 int offset = buf - page_address(page);
569 struct sk_buff *head_skb, *curr_skb;
570 struct bpf_prog *xdp_prog;
571 unsigned int truesize;
572
573 head_skb = NULL;
574
575 rcu_read_lock();
576 xdp_prog = rcu_dereference(rq->xdp_prog);
577 if (xdp_prog) {
578 struct page *xdp_page;
579 u32 act;
580
581 /* This happens when rx buffer size is underestimated */
582 if (unlikely(num_buf > 1)) {
583 /* linearize data for XDP */
584 xdp_page = xdp_linearize_page(rq, &num_buf,
585 page, offset, &len);
586 if (!xdp_page)
587 goto err_xdp;
588 offset = 0;
589 } else {
590 xdp_page = page;
591 }
592
593 /* Transient failure which in theory could occur if
594 * in-flight packets from before XDP was enabled reach
595 * the receive path after XDP is loaded. In practice I
596 * was not able to create this condition.
597 */
598 if (unlikely(hdr->hdr.gso_type))
599 goto err_xdp;
600
601 act = do_xdp_prog(vi, rq, xdp_prog,
602 page_address(xdp_page) + offset, len);
603 switch (act) {
604 case XDP_PASS:
605 /* We can only create skb based on xdp_page. */
606 if (unlikely(xdp_page != page)) {
607 rcu_read_unlock();
608 put_page(page);
609 head_skb = page_to_skb(vi, rq, xdp_page,
610 0, len, PAGE_SIZE);
611 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
612 return head_skb;
613 }
614 break;
615 case XDP_TX:
616 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
617 if (unlikely(xdp_page != page))
618 goto err_xdp;
619 rcu_read_unlock();
620 goto xdp_xmit;
621 case XDP_DROP:
622 default:
623 if (unlikely(xdp_page != page))
624 __free_pages(xdp_page, 0);
625 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
626 goto err_xdp;
627 }
628 }
629 rcu_read_unlock();
630
631 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
632 head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
633 curr_skb = head_skb;
634
635 if (unlikely(!curr_skb))
636 goto err_skb;
637 while (--num_buf) {
638 int num_skb_frags;
639
640 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
641 if (unlikely(!ctx)) {
642 pr_debug("%s: rx error: %d buffers out of %d missing\n",
643 dev->name, num_buf,
644 virtio16_to_cpu(vi->vdev,
645 hdr->num_buffers));
646 dev->stats.rx_length_errors++;
647 goto err_buf;
648 }
649
650 buf = mergeable_ctx_to_buf_address(ctx);
651 page = virt_to_head_page(buf);
652
653 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
654 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
655 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
656
657 if (unlikely(!nskb))
658 goto err_skb;
659 if (curr_skb == head_skb)
660 skb_shinfo(curr_skb)->frag_list = nskb;
661 else
662 curr_skb->next = nskb;
663 curr_skb = nskb;
664 head_skb->truesize += nskb->truesize;
665 num_skb_frags = 0;
666 }
667 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
668 if (curr_skb != head_skb) {
669 head_skb->data_len += len;
670 head_skb->len += len;
671 head_skb->truesize += truesize;
672 }
673 offset = buf - page_address(page);
674 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
675 put_page(page);
676 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
677 len, truesize);
678 } else {
679 skb_add_rx_frag(curr_skb, num_skb_frags, page,
680 offset, len, truesize);
681 }
682 }
683
684 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
685 return head_skb;
686
687 err_xdp:
688 rcu_read_unlock();
689 err_skb:
690 put_page(page);
691 while (--num_buf) {
692 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
693 if (unlikely(!ctx)) {
694 pr_debug("%s: rx error: %d buffers missing\n",
695 dev->name, num_buf);
696 dev->stats.rx_length_errors++;
697 break;
698 }
699 page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx));
700 put_page(page);
701 }
702 err_buf:
703 dev->stats.rx_dropped++;
704 dev_kfree_skb(head_skb);
705 xdp_xmit:
706 return NULL;
707 }
708
709 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
710 void *buf, unsigned int len)
711 {
712 struct net_device *dev = vi->dev;
713 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
714 struct sk_buff *skb;
715 struct virtio_net_hdr_mrg_rxbuf *hdr;
716
717 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
718 pr_debug("%s: short packet %i\n", dev->name, len);
719 dev->stats.rx_length_errors++;
720 if (vi->mergeable_rx_bufs) {
721 unsigned long ctx = (unsigned long)buf;
722 void *base = mergeable_ctx_to_buf_address(ctx);
723 put_page(virt_to_head_page(base));
724 } else if (vi->big_packets) {
725 give_pages(rq, buf);
726 } else {
727 dev_kfree_skb(buf);
728 }
729 return;
730 }
731
732 if (vi->mergeable_rx_bufs)
733 skb = receive_mergeable(dev, vi, rq, (unsigned long)buf, len);
734 else if (vi->big_packets)
735 skb = receive_big(dev, vi, rq, buf, len);
736 else
737 skb = receive_small(dev, vi, rq, buf, len);
738
739 if (unlikely(!skb))
740 return;
741
742 hdr = skb_vnet_hdr(skb);
743
744 u64_stats_update_begin(&stats->rx_syncp);
745 stats->rx_bytes += skb->len;
746 stats->rx_packets++;
747 u64_stats_update_end(&stats->rx_syncp);
748
749 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
750 skb->ip_summed = CHECKSUM_UNNECESSARY;
751
752 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
753 virtio_is_little_endian(vi->vdev))) {
754 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
755 dev->name, hdr->hdr.gso_type,
756 hdr->hdr.gso_size);
757 goto frame_err;
758 }
759
760 skb->protocol = eth_type_trans(skb, dev);
761 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
762 ntohs(skb->protocol), skb->len, skb->pkt_type);
763
764 napi_gro_receive(&rq->napi, skb);
765 return;
766
767 frame_err:
768 dev->stats.rx_frame_errors++;
769 dev_kfree_skb(skb);
770 }
771
772 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
773 gfp_t gfp)
774 {
775 struct sk_buff *skb;
776 struct virtio_net_hdr_mrg_rxbuf *hdr;
777 int err;
778
779 skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp);
780 if (unlikely(!skb))
781 return -ENOMEM;
782
783 skb_put(skb, GOOD_PACKET_LEN);
784
785 hdr = skb_vnet_hdr(skb);
786 sg_init_table(rq->sg, 2);
787 sg_set_buf(rq->sg, hdr, vi->hdr_len);
788 skb_to_sgvec(skb, rq->sg + 1, 0, skb->len);
789
790 err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp);
791 if (err < 0)
792 dev_kfree_skb(skb);
793
794 return err;
795 }
796
797 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
798 gfp_t gfp)
799 {
800 struct page *first, *list = NULL;
801 char *p;
802 int i, err, offset;
803
804 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
805
806 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
807 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
808 first = get_a_page(rq, gfp);
809 if (!first) {
810 if (list)
811 give_pages(rq, list);
812 return -ENOMEM;
813 }
814 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
815
816 /* chain new page in list head to match sg */
817 first->private = (unsigned long)list;
818 list = first;
819 }
820
821 first = get_a_page(rq, gfp);
822 if (!first) {
823 give_pages(rq, list);
824 return -ENOMEM;
825 }
826 p = page_address(first);
827
828 /* rq->sg[0], rq->sg[1] share the same page */
829 /* a separated rq->sg[0] for header - required in case !any_header_sg */
830 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
831
832 /* rq->sg[1] for data packet, from offset */
833 offset = sizeof(struct padded_vnet_hdr);
834 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
835
836 /* chain first in list head */
837 first->private = (unsigned long)list;
838 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
839 first, gfp);
840 if (err < 0)
841 give_pages(rq, first);
842
843 return err;
844 }
845
846 static unsigned int get_mergeable_buf_len(struct ewma_pkt_len *avg_pkt_len)
847 {
848 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
849 unsigned int len;
850
851 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
852 GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
853 return ALIGN(len, MERGEABLE_BUFFER_ALIGN);
854 }
855
856 static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
857 {
858 struct page_frag *alloc_frag = &rq->alloc_frag;
859 char *buf;
860 unsigned long ctx;
861 int err;
862 unsigned int len, hole;
863
864 len = get_mergeable_buf_len(&rq->mrg_avg_pkt_len);
865 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
866 return -ENOMEM;
867
868 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
869 ctx = mergeable_buf_to_ctx(buf, len);
870 get_page(alloc_frag->page);
871 alloc_frag->offset += len;
872 hole = alloc_frag->size - alloc_frag->offset;
873 if (hole < len) {
874 /* To avoid internal fragmentation, if there is very likely not
875 * enough space for another buffer, add the remaining space to
876 * the current buffer. This extra space is not included in
877 * the truesize stored in ctx.
878 */
879 len += hole;
880 alloc_frag->offset += hole;
881 }
882
883 sg_init_one(rq->sg, buf, len);
884 err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, (void *)ctx, gfp);
885 if (err < 0)
886 put_page(virt_to_head_page(buf));
887
888 return err;
889 }
890
891 /*
892 * Returns false if we couldn't fill entirely (OOM).
893 *
894 * Normally run in the receive path, but can also be run from ndo_open
895 * before we're receiving packets, or from refill_work which is
896 * careful to disable receiving (using napi_disable).
897 */
898 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
899 gfp_t gfp)
900 {
901 int err;
902 bool oom;
903
904 gfp |= __GFP_COLD;
905 do {
906 if (vi->mergeable_rx_bufs)
907 err = add_recvbuf_mergeable(rq, gfp);
908 else if (vi->big_packets)
909 err = add_recvbuf_big(vi, rq, gfp);
910 else
911 err = add_recvbuf_small(vi, rq, gfp);
912
913 oom = err == -ENOMEM;
914 if (err)
915 break;
916 } while (rq->vq->num_free);
917 virtqueue_kick(rq->vq);
918 return !oom;
919 }
920
921 static void skb_recv_done(struct virtqueue *rvq)
922 {
923 struct virtnet_info *vi = rvq->vdev->priv;
924 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
925
926 /* Schedule NAPI, Suppress further interrupts if successful. */
927 if (napi_schedule_prep(&rq->napi)) {
928 virtqueue_disable_cb(rvq);
929 __napi_schedule(&rq->napi);
930 }
931 }
932
933 static void virtnet_napi_enable(struct receive_queue *rq)
934 {
935 napi_enable(&rq->napi);
936
937 /* If all buffers were filled by other side before we napi_enabled, we
938 * won't get another interrupt, so process any outstanding packets
939 * now. virtnet_poll wants re-enable the queue, so we disable here.
940 * We synchronize against interrupts via NAPI_STATE_SCHED */
941 if (napi_schedule_prep(&rq->napi)) {
942 virtqueue_disable_cb(rq->vq);
943 local_bh_disable();
944 __napi_schedule(&rq->napi);
945 local_bh_enable();
946 }
947 }
948
949 static void refill_work(struct work_struct *work)
950 {
951 struct virtnet_info *vi =
952 container_of(work, struct virtnet_info, refill.work);
953 bool still_empty;
954 int i;
955
956 for (i = 0; i < vi->curr_queue_pairs; i++) {
957 struct receive_queue *rq = &vi->rq[i];
958
959 napi_disable(&rq->napi);
960 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
961 virtnet_napi_enable(rq);
962
963 /* In theory, this can happen: if we don't get any buffers in
964 * we will *never* try to fill again.
965 */
966 if (still_empty)
967 schedule_delayed_work(&vi->refill, HZ/2);
968 }
969 }
970
971 static int virtnet_receive(struct receive_queue *rq, int budget)
972 {
973 struct virtnet_info *vi = rq->vq->vdev->priv;
974 unsigned int len, received = 0;
975 void *buf;
976
977 while (received < budget &&
978 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
979 receive_buf(vi, rq, buf, len);
980 received++;
981 }
982
983 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
984 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
985 schedule_delayed_work(&vi->refill, 0);
986 }
987
988 return received;
989 }
990
991 static int virtnet_poll(struct napi_struct *napi, int budget)
992 {
993 struct receive_queue *rq =
994 container_of(napi, struct receive_queue, napi);
995 unsigned int r, received;
996
997 received = virtnet_receive(rq, budget);
998
999 /* Out of packets? */
1000 if (received < budget) {
1001 r = virtqueue_enable_cb_prepare(rq->vq);
1002 napi_complete_done(napi, received);
1003 if (unlikely(virtqueue_poll(rq->vq, r)) &&
1004 napi_schedule_prep(napi)) {
1005 virtqueue_disable_cb(rq->vq);
1006 __napi_schedule(napi);
1007 }
1008 }
1009
1010 return received;
1011 }
1012
1013 #ifdef CONFIG_NET_RX_BUSY_POLL
1014 /* must be called with local_bh_disable()d */
1015 static int virtnet_busy_poll(struct napi_struct *napi)
1016 {
1017 struct receive_queue *rq =
1018 container_of(napi, struct receive_queue, napi);
1019 struct virtnet_info *vi = rq->vq->vdev->priv;
1020 int r, received = 0, budget = 4;
1021
1022 if (!(vi->status & VIRTIO_NET_S_LINK_UP))
1023 return LL_FLUSH_FAILED;
1024
1025 if (!napi_schedule_prep(napi))
1026 return LL_FLUSH_BUSY;
1027
1028 virtqueue_disable_cb(rq->vq);
1029
1030 again:
1031 received += virtnet_receive(rq, budget);
1032
1033 r = virtqueue_enable_cb_prepare(rq->vq);
1034 clear_bit(NAPI_STATE_SCHED, &napi->state);
1035 if (unlikely(virtqueue_poll(rq->vq, r)) &&
1036 napi_schedule_prep(napi)) {
1037 virtqueue_disable_cb(rq->vq);
1038 if (received < budget) {
1039 budget -= received;
1040 goto again;
1041 } else {
1042 __napi_schedule(napi);
1043 }
1044 }
1045
1046 return received;
1047 }
1048 #endif /* CONFIG_NET_RX_BUSY_POLL */
1049
1050 static int virtnet_open(struct net_device *dev)
1051 {
1052 struct virtnet_info *vi = netdev_priv(dev);
1053 int i;
1054
1055 for (i = 0; i < vi->max_queue_pairs; i++) {
1056 if (i < vi->curr_queue_pairs)
1057 /* Make sure we have some buffers: if oom use wq. */
1058 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1059 schedule_delayed_work(&vi->refill, 0);
1060 virtnet_napi_enable(&vi->rq[i]);
1061 }
1062
1063 return 0;
1064 }
1065
1066 static void free_old_xmit_skbs(struct send_queue *sq)
1067 {
1068 struct sk_buff *skb;
1069 unsigned int len;
1070 struct virtnet_info *vi = sq->vq->vdev->priv;
1071 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1072
1073 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1074 pr_debug("Sent skb %p\n", skb);
1075
1076 u64_stats_update_begin(&stats->tx_syncp);
1077 stats->tx_bytes += skb->len;
1078 stats->tx_packets++;
1079 u64_stats_update_end(&stats->tx_syncp);
1080
1081 dev_kfree_skb_any(skb);
1082 }
1083 }
1084
1085 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1086 {
1087 struct virtio_net_hdr_mrg_rxbuf *hdr;
1088 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1089 struct virtnet_info *vi = sq->vq->vdev->priv;
1090 unsigned num_sg;
1091 unsigned hdr_len = vi->hdr_len;
1092 bool can_push;
1093
1094 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1095
1096 can_push = vi->any_header_sg &&
1097 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1098 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1099 /* Even if we can, don't push here yet as this would skew
1100 * csum_start offset below. */
1101 if (can_push)
1102 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1103 else
1104 hdr = skb_vnet_hdr(skb);
1105
1106 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1107 virtio_is_little_endian(vi->vdev)))
1108 BUG();
1109
1110 if (vi->mergeable_rx_bufs)
1111 hdr->num_buffers = 0;
1112
1113 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1114 if (can_push) {
1115 __skb_push(skb, hdr_len);
1116 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1117 /* Pull header back to avoid skew in tx bytes calculations. */
1118 __skb_pull(skb, hdr_len);
1119 } else {
1120 sg_set_buf(sq->sg, hdr, hdr_len);
1121 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
1122 }
1123 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1124 }
1125
1126 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1127 {
1128 struct virtnet_info *vi = netdev_priv(dev);
1129 int qnum = skb_get_queue_mapping(skb);
1130 struct send_queue *sq = &vi->sq[qnum];
1131 int err;
1132 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1133 bool kick = !skb->xmit_more;
1134
1135 /* Free up any pending old buffers before queueing new ones. */
1136 free_old_xmit_skbs(sq);
1137
1138 /* timestamp packet in software */
1139 skb_tx_timestamp(skb);
1140
1141 /* Try to transmit */
1142 err = xmit_skb(sq, skb);
1143
1144 /* This should not happen! */
1145 if (unlikely(err)) {
1146 dev->stats.tx_fifo_errors++;
1147 if (net_ratelimit())
1148 dev_warn(&dev->dev,
1149 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
1150 dev->stats.tx_dropped++;
1151 dev_kfree_skb_any(skb);
1152 return NETDEV_TX_OK;
1153 }
1154
1155 /* Don't wait up for transmitted skbs to be freed. */
1156 skb_orphan(skb);
1157 nf_reset(skb);
1158
1159 /* If running out of space, stop queue to avoid getting packets that we
1160 * are then unable to transmit.
1161 * An alternative would be to force queuing layer to requeue the skb by
1162 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1163 * returned in a normal path of operation: it means that driver is not
1164 * maintaining the TX queue stop/start state properly, and causes
1165 * the stack to do a non-trivial amount of useless work.
1166 * Since most packets only take 1 or 2 ring slots, stopping the queue
1167 * early means 16 slots are typically wasted.
1168 */
1169 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1170 netif_stop_subqueue(dev, qnum);
1171 if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1172 /* More just got used, free them then recheck. */
1173 free_old_xmit_skbs(sq);
1174 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1175 netif_start_subqueue(dev, qnum);
1176 virtqueue_disable_cb(sq->vq);
1177 }
1178 }
1179 }
1180
1181 if (kick || netif_xmit_stopped(txq))
1182 virtqueue_kick(sq->vq);
1183
1184 return NETDEV_TX_OK;
1185 }
1186
1187 /*
1188 * Send command via the control virtqueue and check status. Commands
1189 * supported by the hypervisor, as indicated by feature bits, should
1190 * never fail unless improperly formatted.
1191 */
1192 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1193 struct scatterlist *out)
1194 {
1195 struct scatterlist *sgs[4], hdr, stat;
1196 unsigned out_num = 0, tmp;
1197
1198 /* Caller should know better */
1199 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1200
1201 vi->ctrl_status = ~0;
1202 vi->ctrl_hdr.class = class;
1203 vi->ctrl_hdr.cmd = cmd;
1204 /* Add header */
1205 sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
1206 sgs[out_num++] = &hdr;
1207
1208 if (out)
1209 sgs[out_num++] = out;
1210
1211 /* Add return status. */
1212 sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
1213 sgs[out_num] = &stat;
1214
1215 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1216 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1217
1218 if (unlikely(!virtqueue_kick(vi->cvq)))
1219 return vi->ctrl_status == VIRTIO_NET_OK;
1220
1221 /* Spin for a response, the kick causes an ioport write, trapping
1222 * into the hypervisor, so the request should be handled immediately.
1223 */
1224 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1225 !virtqueue_is_broken(vi->cvq))
1226 cpu_relax();
1227
1228 return vi->ctrl_status == VIRTIO_NET_OK;
1229 }
1230
1231 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1232 {
1233 struct virtnet_info *vi = netdev_priv(dev);
1234 struct virtio_device *vdev = vi->vdev;
1235 int ret;
1236 struct sockaddr *addr;
1237 struct scatterlist sg;
1238
1239 addr = kmalloc(sizeof(*addr), GFP_KERNEL);
1240 if (!addr)
1241 return -ENOMEM;
1242 memcpy(addr, p, sizeof(*addr));
1243
1244 ret = eth_prepare_mac_addr_change(dev, addr);
1245 if (ret)
1246 goto out;
1247
1248 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1249 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1250 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1251 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1252 dev_warn(&vdev->dev,
1253 "Failed to set mac address by vq command.\n");
1254 ret = -EINVAL;
1255 goto out;
1256 }
1257 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1258 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1259 unsigned int i;
1260
1261 /* Naturally, this has an atomicity problem. */
1262 for (i = 0; i < dev->addr_len; i++)
1263 virtio_cwrite8(vdev,
1264 offsetof(struct virtio_net_config, mac) +
1265 i, addr->sa_data[i]);
1266 }
1267
1268 eth_commit_mac_addr_change(dev, p);
1269 ret = 0;
1270
1271 out:
1272 kfree(addr);
1273 return ret;
1274 }
1275
1276 static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,
1277 struct rtnl_link_stats64 *tot)
1278 {
1279 struct virtnet_info *vi = netdev_priv(dev);
1280 int cpu;
1281 unsigned int start;
1282
1283 for_each_possible_cpu(cpu) {
1284 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1285 u64 tpackets, tbytes, rpackets, rbytes;
1286
1287 do {
1288 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1289 tpackets = stats->tx_packets;
1290 tbytes = stats->tx_bytes;
1291 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1292
1293 do {
1294 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1295 rpackets = stats->rx_packets;
1296 rbytes = stats->rx_bytes;
1297 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1298
1299 tot->rx_packets += rpackets;
1300 tot->tx_packets += tpackets;
1301 tot->rx_bytes += rbytes;
1302 tot->tx_bytes += tbytes;
1303 }
1304
1305 tot->tx_dropped = dev->stats.tx_dropped;
1306 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1307 tot->rx_dropped = dev->stats.rx_dropped;
1308 tot->rx_length_errors = dev->stats.rx_length_errors;
1309 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1310
1311 return tot;
1312 }
1313
1314 #ifdef CONFIG_NET_POLL_CONTROLLER
1315 static void virtnet_netpoll(struct net_device *dev)
1316 {
1317 struct virtnet_info *vi = netdev_priv(dev);
1318 int i;
1319
1320 for (i = 0; i < vi->curr_queue_pairs; i++)
1321 napi_schedule(&vi->rq[i].napi);
1322 }
1323 #endif
1324
1325 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1326 {
1327 rtnl_lock();
1328 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1329 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1330 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1331 rtnl_unlock();
1332 }
1333
1334 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1335 {
1336 struct scatterlist sg;
1337 struct net_device *dev = vi->dev;
1338
1339 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1340 return 0;
1341
1342 vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1343 sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq));
1344
1345 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1346 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1347 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1348 queue_pairs);
1349 return -EINVAL;
1350 } else {
1351 vi->curr_queue_pairs = queue_pairs;
1352 /* virtnet_open() will refill when device is going to up. */
1353 if (dev->flags & IFF_UP)
1354 schedule_delayed_work(&vi->refill, 0);
1355 }
1356
1357 return 0;
1358 }
1359
1360 static int virtnet_close(struct net_device *dev)
1361 {
1362 struct virtnet_info *vi = netdev_priv(dev);
1363 int i;
1364
1365 /* Make sure refill_work doesn't re-enable napi! */
1366 cancel_delayed_work_sync(&vi->refill);
1367
1368 for (i = 0; i < vi->max_queue_pairs; i++)
1369 napi_disable(&vi->rq[i].napi);
1370
1371 return 0;
1372 }
1373
1374 static void virtnet_set_rx_mode(struct net_device *dev)
1375 {
1376 struct virtnet_info *vi = netdev_priv(dev);
1377 struct scatterlist sg[2];
1378 struct virtio_net_ctrl_mac *mac_data;
1379 struct netdev_hw_addr *ha;
1380 int uc_count;
1381 int mc_count;
1382 void *buf;
1383 int i;
1384
1385 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1386 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1387 return;
1388
1389 vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
1390 vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1391
1392 sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
1393
1394 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1395 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1396 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1397 vi->ctrl_promisc ? "en" : "dis");
1398
1399 sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
1400
1401 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1402 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1403 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1404 vi->ctrl_allmulti ? "en" : "dis");
1405
1406 uc_count = netdev_uc_count(dev);
1407 mc_count = netdev_mc_count(dev);
1408 /* MAC filter - use one buffer for both lists */
1409 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1410 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1411 mac_data = buf;
1412 if (!buf)
1413 return;
1414
1415 sg_init_table(sg, 2);
1416
1417 /* Store the unicast list and count in the front of the buffer */
1418 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1419 i = 0;
1420 netdev_for_each_uc_addr(ha, dev)
1421 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1422
1423 sg_set_buf(&sg[0], mac_data,
1424 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1425
1426 /* multicast list and count fill the end */
1427 mac_data = (void *)&mac_data->macs[uc_count][0];
1428
1429 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1430 i = 0;
1431 netdev_for_each_mc_addr(ha, dev)
1432 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1433
1434 sg_set_buf(&sg[1], mac_data,
1435 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1436
1437 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1438 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1439 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1440
1441 kfree(buf);
1442 }
1443
1444 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1445 __be16 proto, u16 vid)
1446 {
1447 struct virtnet_info *vi = netdev_priv(dev);
1448 struct scatterlist sg;
1449
1450 vi->ctrl_vid = vid;
1451 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1452
1453 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1454 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1455 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1456 return 0;
1457 }
1458
1459 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1460 __be16 proto, u16 vid)
1461 {
1462 struct virtnet_info *vi = netdev_priv(dev);
1463 struct scatterlist sg;
1464
1465 vi->ctrl_vid = vid;
1466 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1467
1468 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1469 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1470 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1471 return 0;
1472 }
1473
1474 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1475 {
1476 int i;
1477
1478 if (vi->affinity_hint_set) {
1479 for (i = 0; i < vi->max_queue_pairs; i++) {
1480 virtqueue_set_affinity(vi->rq[i].vq, -1);
1481 virtqueue_set_affinity(vi->sq[i].vq, -1);
1482 }
1483
1484 vi->affinity_hint_set = false;
1485 }
1486 }
1487
1488 static void virtnet_set_affinity(struct virtnet_info *vi)
1489 {
1490 int i;
1491 int cpu;
1492
1493 /* In multiqueue mode, when the number of cpu is equal to the number of
1494 * queue pairs, we let the queue pairs to be private to one cpu by
1495 * setting the affinity hint to eliminate the contention.
1496 */
1497 if (vi->curr_queue_pairs == 1 ||
1498 vi->max_queue_pairs != num_online_cpus()) {
1499 virtnet_clean_affinity(vi, -1);
1500 return;
1501 }
1502
1503 i = 0;
1504 for_each_online_cpu(cpu) {
1505 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1506 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1507 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1508 i++;
1509 }
1510
1511 vi->affinity_hint_set = true;
1512 }
1513
1514 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1515 {
1516 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1517 node);
1518 virtnet_set_affinity(vi);
1519 return 0;
1520 }
1521
1522 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1523 {
1524 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1525 node_dead);
1526 virtnet_set_affinity(vi);
1527 return 0;
1528 }
1529
1530 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1531 {
1532 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1533 node);
1534
1535 virtnet_clean_affinity(vi, cpu);
1536 return 0;
1537 }
1538
1539 static enum cpuhp_state virtionet_online;
1540
1541 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1542 {
1543 int ret;
1544
1545 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
1546 if (ret)
1547 return ret;
1548 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1549 &vi->node_dead);
1550 if (!ret)
1551 return ret;
1552 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1553 return ret;
1554 }
1555
1556 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
1557 {
1558 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1559 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1560 &vi->node_dead);
1561 }
1562
1563 static void virtnet_get_ringparam(struct net_device *dev,
1564 struct ethtool_ringparam *ring)
1565 {
1566 struct virtnet_info *vi = netdev_priv(dev);
1567
1568 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1569 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1570 ring->rx_pending = ring->rx_max_pending;
1571 ring->tx_pending = ring->tx_max_pending;
1572 }
1573
1574
1575 static void virtnet_get_drvinfo(struct net_device *dev,
1576 struct ethtool_drvinfo *info)
1577 {
1578 struct virtnet_info *vi = netdev_priv(dev);
1579 struct virtio_device *vdev = vi->vdev;
1580
1581 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1582 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1583 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1584
1585 }
1586
1587 /* TODO: Eliminate OOO packets during switching */
1588 static int virtnet_set_channels(struct net_device *dev,
1589 struct ethtool_channels *channels)
1590 {
1591 struct virtnet_info *vi = netdev_priv(dev);
1592 u16 queue_pairs = channels->combined_count;
1593 int err;
1594
1595 /* We don't support separate rx/tx channels.
1596 * We don't allow setting 'other' channels.
1597 */
1598 if (channels->rx_count || channels->tx_count || channels->other_count)
1599 return -EINVAL;
1600
1601 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1602 return -EINVAL;
1603
1604 /* For now we don't support modifying channels while XDP is loaded
1605 * also when XDP is loaded all RX queues have XDP programs so we only
1606 * need to check a single RX queue.
1607 */
1608 if (vi->rq[0].xdp_prog)
1609 return -EINVAL;
1610
1611 get_online_cpus();
1612 err = virtnet_set_queues(vi, queue_pairs);
1613 if (!err) {
1614 netif_set_real_num_tx_queues(dev, queue_pairs);
1615 netif_set_real_num_rx_queues(dev, queue_pairs);
1616
1617 virtnet_set_affinity(vi);
1618 }
1619 put_online_cpus();
1620
1621 return err;
1622 }
1623
1624 static void virtnet_get_channels(struct net_device *dev,
1625 struct ethtool_channels *channels)
1626 {
1627 struct virtnet_info *vi = netdev_priv(dev);
1628
1629 channels->combined_count = vi->curr_queue_pairs;
1630 channels->max_combined = vi->max_queue_pairs;
1631 channels->max_other = 0;
1632 channels->rx_count = 0;
1633 channels->tx_count = 0;
1634 channels->other_count = 0;
1635 }
1636
1637 /* Check if the user is trying to change anything besides speed/duplex */
1638 static bool virtnet_validate_ethtool_cmd(const struct ethtool_cmd *cmd)
1639 {
1640 struct ethtool_cmd diff1 = *cmd;
1641 struct ethtool_cmd diff2 = {};
1642
1643 /* cmd is always set so we need to clear it, validate the port type
1644 * and also without autonegotiation we can ignore advertising
1645 */
1646 ethtool_cmd_speed_set(&diff1, 0);
1647 diff2.port = PORT_OTHER;
1648 diff1.advertising = 0;
1649 diff1.duplex = 0;
1650 diff1.cmd = 0;
1651
1652 return !memcmp(&diff1, &diff2, sizeof(diff1));
1653 }
1654
1655 static int virtnet_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1656 {
1657 struct virtnet_info *vi = netdev_priv(dev);
1658 u32 speed;
1659
1660 speed = ethtool_cmd_speed(cmd);
1661 /* don't allow custom speed and duplex */
1662 if (!ethtool_validate_speed(speed) ||
1663 !ethtool_validate_duplex(cmd->duplex) ||
1664 !virtnet_validate_ethtool_cmd(cmd))
1665 return -EINVAL;
1666 vi->speed = speed;
1667 vi->duplex = cmd->duplex;
1668
1669 return 0;
1670 }
1671
1672 static int virtnet_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1673 {
1674 struct virtnet_info *vi = netdev_priv(dev);
1675
1676 ethtool_cmd_speed_set(cmd, vi->speed);
1677 cmd->duplex = vi->duplex;
1678 cmd->port = PORT_OTHER;
1679
1680 return 0;
1681 }
1682
1683 static void virtnet_init_settings(struct net_device *dev)
1684 {
1685 struct virtnet_info *vi = netdev_priv(dev);
1686
1687 vi->speed = SPEED_UNKNOWN;
1688 vi->duplex = DUPLEX_UNKNOWN;
1689 }
1690
1691 static const struct ethtool_ops virtnet_ethtool_ops = {
1692 .get_drvinfo = virtnet_get_drvinfo,
1693 .get_link = ethtool_op_get_link,
1694 .get_ringparam = virtnet_get_ringparam,
1695 .set_channels = virtnet_set_channels,
1696 .get_channels = virtnet_get_channels,
1697 .get_ts_info = ethtool_op_get_ts_info,
1698 .get_settings = virtnet_get_settings,
1699 .set_settings = virtnet_set_settings,
1700 };
1701
1702 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog)
1703 {
1704 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
1705 struct virtnet_info *vi = netdev_priv(dev);
1706 struct bpf_prog *old_prog;
1707 u16 xdp_qp = 0, curr_qp;
1708 int i, err;
1709
1710 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1711 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1712 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
1713 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO)) {
1714 netdev_warn(dev, "can't set XDP while host is implementing LRO, disable LRO first\n");
1715 return -EOPNOTSUPP;
1716 }
1717
1718 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
1719 netdev_warn(dev, "XDP expects header/data in single page, any_header_sg required\n");
1720 return -EINVAL;
1721 }
1722
1723 if (dev->mtu > max_sz) {
1724 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
1725 return -EINVAL;
1726 }
1727
1728 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
1729 if (prog)
1730 xdp_qp = nr_cpu_ids;
1731
1732 /* XDP requires extra queues for XDP_TX */
1733 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
1734 netdev_warn(dev, "request %i queues but max is %i\n",
1735 curr_qp + xdp_qp, vi->max_queue_pairs);
1736 return -ENOMEM;
1737 }
1738
1739 err = virtnet_set_queues(vi, curr_qp + xdp_qp);
1740 if (err) {
1741 dev_warn(&dev->dev, "XDP Device queue allocation failure.\n");
1742 return err;
1743 }
1744
1745 if (prog) {
1746 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
1747 if (IS_ERR(prog)) {
1748 virtnet_set_queues(vi, curr_qp);
1749 return PTR_ERR(prog);
1750 }
1751 }
1752
1753 vi->xdp_queue_pairs = xdp_qp;
1754 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
1755
1756 for (i = 0; i < vi->max_queue_pairs; i++) {
1757 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
1758 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
1759 if (old_prog)
1760 bpf_prog_put(old_prog);
1761 }
1762
1763 return 0;
1764 }
1765
1766 static bool virtnet_xdp_query(struct net_device *dev)
1767 {
1768 struct virtnet_info *vi = netdev_priv(dev);
1769 int i;
1770
1771 for (i = 0; i < vi->max_queue_pairs; i++) {
1772 if (vi->rq[i].xdp_prog)
1773 return true;
1774 }
1775 return false;
1776 }
1777
1778 static int virtnet_xdp(struct net_device *dev, struct netdev_xdp *xdp)
1779 {
1780 switch (xdp->command) {
1781 case XDP_SETUP_PROG:
1782 return virtnet_xdp_set(dev, xdp->prog);
1783 case XDP_QUERY_PROG:
1784 xdp->prog_attached = virtnet_xdp_query(dev);
1785 return 0;
1786 default:
1787 return -EINVAL;
1788 }
1789 }
1790
1791 static const struct net_device_ops virtnet_netdev = {
1792 .ndo_open = virtnet_open,
1793 .ndo_stop = virtnet_close,
1794 .ndo_start_xmit = start_xmit,
1795 .ndo_validate_addr = eth_validate_addr,
1796 .ndo_set_mac_address = virtnet_set_mac_address,
1797 .ndo_set_rx_mode = virtnet_set_rx_mode,
1798 .ndo_get_stats64 = virtnet_stats,
1799 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
1800 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
1801 #ifdef CONFIG_NET_POLL_CONTROLLER
1802 .ndo_poll_controller = virtnet_netpoll,
1803 #endif
1804 #ifdef CONFIG_NET_RX_BUSY_POLL
1805 .ndo_busy_poll = virtnet_busy_poll,
1806 #endif
1807 .ndo_xdp = virtnet_xdp,
1808 };
1809
1810 static void virtnet_config_changed_work(struct work_struct *work)
1811 {
1812 struct virtnet_info *vi =
1813 container_of(work, struct virtnet_info, config_work);
1814 u16 v;
1815
1816 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
1817 struct virtio_net_config, status, &v) < 0)
1818 return;
1819
1820 if (v & VIRTIO_NET_S_ANNOUNCE) {
1821 netdev_notify_peers(vi->dev);
1822 virtnet_ack_link_announce(vi);
1823 }
1824
1825 /* Ignore unknown (future) status bits */
1826 v &= VIRTIO_NET_S_LINK_UP;
1827
1828 if (vi->status == v)
1829 return;
1830
1831 vi->status = v;
1832
1833 if (vi->status & VIRTIO_NET_S_LINK_UP) {
1834 netif_carrier_on(vi->dev);
1835 netif_tx_wake_all_queues(vi->dev);
1836 } else {
1837 netif_carrier_off(vi->dev);
1838 netif_tx_stop_all_queues(vi->dev);
1839 }
1840 }
1841
1842 static void virtnet_config_changed(struct virtio_device *vdev)
1843 {
1844 struct virtnet_info *vi = vdev->priv;
1845
1846 schedule_work(&vi->config_work);
1847 }
1848
1849 static void virtnet_free_queues(struct virtnet_info *vi)
1850 {
1851 int i;
1852
1853 for (i = 0; i < vi->max_queue_pairs; i++) {
1854 napi_hash_del(&vi->rq[i].napi);
1855 netif_napi_del(&vi->rq[i].napi);
1856 }
1857
1858 /* We called napi_hash_del() before netif_napi_del(),
1859 * we need to respect an RCU grace period before freeing vi->rq
1860 */
1861 synchronize_net();
1862
1863 kfree(vi->rq);
1864 kfree(vi->sq);
1865 }
1866
1867 static void free_receive_bufs(struct virtnet_info *vi)
1868 {
1869 struct bpf_prog *old_prog;
1870 int i;
1871
1872 rtnl_lock();
1873 for (i = 0; i < vi->max_queue_pairs; i++) {
1874 while (vi->rq[i].pages)
1875 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
1876
1877 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
1878 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
1879 if (old_prog)
1880 bpf_prog_put(old_prog);
1881 }
1882 rtnl_unlock();
1883 }
1884
1885 static void free_receive_page_frags(struct virtnet_info *vi)
1886 {
1887 int i;
1888 for (i = 0; i < vi->max_queue_pairs; i++)
1889 if (vi->rq[i].alloc_frag.page)
1890 put_page(vi->rq[i].alloc_frag.page);
1891 }
1892
1893 static bool is_xdp_queue(struct virtnet_info *vi, int q)
1894 {
1895 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
1896 return false;
1897 else if (q < vi->curr_queue_pairs)
1898 return true;
1899 else
1900 return false;
1901 }
1902
1903 static void free_unused_bufs(struct virtnet_info *vi)
1904 {
1905 void *buf;
1906 int i;
1907
1908 for (i = 0; i < vi->max_queue_pairs; i++) {
1909 struct virtqueue *vq = vi->sq[i].vq;
1910 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
1911 if (!is_xdp_queue(vi, i))
1912 dev_kfree_skb(buf);
1913 else
1914 put_page(virt_to_head_page(buf));
1915 }
1916 }
1917
1918 for (i = 0; i < vi->max_queue_pairs; i++) {
1919 struct virtqueue *vq = vi->rq[i].vq;
1920
1921 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
1922 if (vi->mergeable_rx_bufs) {
1923 unsigned long ctx = (unsigned long)buf;
1924 void *base = mergeable_ctx_to_buf_address(ctx);
1925 put_page(virt_to_head_page(base));
1926 } else if (vi->big_packets) {
1927 give_pages(&vi->rq[i], buf);
1928 } else {
1929 dev_kfree_skb(buf);
1930 }
1931 }
1932 }
1933 }
1934
1935 static void virtnet_del_vqs(struct virtnet_info *vi)
1936 {
1937 struct virtio_device *vdev = vi->vdev;
1938
1939 virtnet_clean_affinity(vi, -1);
1940
1941 vdev->config->del_vqs(vdev);
1942
1943 virtnet_free_queues(vi);
1944 }
1945
1946 static int virtnet_find_vqs(struct virtnet_info *vi)
1947 {
1948 vq_callback_t **callbacks;
1949 struct virtqueue **vqs;
1950 int ret = -ENOMEM;
1951 int i, total_vqs;
1952 const char **names;
1953
1954 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
1955 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
1956 * possible control vq.
1957 */
1958 total_vqs = vi->max_queue_pairs * 2 +
1959 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
1960
1961 /* Allocate space for find_vqs parameters */
1962 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
1963 if (!vqs)
1964 goto err_vq;
1965 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
1966 if (!callbacks)
1967 goto err_callback;
1968 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
1969 if (!names)
1970 goto err_names;
1971
1972 /* Parameters for control virtqueue, if any */
1973 if (vi->has_cvq) {
1974 callbacks[total_vqs - 1] = NULL;
1975 names[total_vqs - 1] = "control";
1976 }
1977
1978 /* Allocate/initialize parameters for send/receive virtqueues */
1979 for (i = 0; i < vi->max_queue_pairs; i++) {
1980 callbacks[rxq2vq(i)] = skb_recv_done;
1981 callbacks[txq2vq(i)] = skb_xmit_done;
1982 sprintf(vi->rq[i].name, "input.%d", i);
1983 sprintf(vi->sq[i].name, "output.%d", i);
1984 names[rxq2vq(i)] = vi->rq[i].name;
1985 names[txq2vq(i)] = vi->sq[i].name;
1986 }
1987
1988 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
1989 names);
1990 if (ret)
1991 goto err_find;
1992
1993 if (vi->has_cvq) {
1994 vi->cvq = vqs[total_vqs - 1];
1995 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
1996 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1997 }
1998
1999 for (i = 0; i < vi->max_queue_pairs; i++) {
2000 vi->rq[i].vq = vqs[rxq2vq(i)];
2001 vi->sq[i].vq = vqs[txq2vq(i)];
2002 }
2003
2004 kfree(names);
2005 kfree(callbacks);
2006 kfree(vqs);
2007
2008 return 0;
2009
2010 err_find:
2011 kfree(names);
2012 err_names:
2013 kfree(callbacks);
2014 err_callback:
2015 kfree(vqs);
2016 err_vq:
2017 return ret;
2018 }
2019
2020 static int virtnet_alloc_queues(struct virtnet_info *vi)
2021 {
2022 int i;
2023
2024 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
2025 if (!vi->sq)
2026 goto err_sq;
2027 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
2028 if (!vi->rq)
2029 goto err_rq;
2030
2031 INIT_DELAYED_WORK(&vi->refill, refill_work);
2032 for (i = 0; i < vi->max_queue_pairs; i++) {
2033 vi->rq[i].pages = NULL;
2034 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2035 napi_weight);
2036
2037 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2038 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2039 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2040 }
2041
2042 return 0;
2043
2044 err_rq:
2045 kfree(vi->sq);
2046 err_sq:
2047 return -ENOMEM;
2048 }
2049
2050 static int init_vqs(struct virtnet_info *vi)
2051 {
2052 int ret;
2053
2054 /* Allocate send & receive queues */
2055 ret = virtnet_alloc_queues(vi);
2056 if (ret)
2057 goto err;
2058
2059 ret = virtnet_find_vqs(vi);
2060 if (ret)
2061 goto err_free;
2062
2063 get_online_cpus();
2064 virtnet_set_affinity(vi);
2065 put_online_cpus();
2066
2067 return 0;
2068
2069 err_free:
2070 virtnet_free_queues(vi);
2071 err:
2072 return ret;
2073 }
2074
2075 #ifdef CONFIG_SYSFS
2076 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2077 struct rx_queue_attribute *attribute, char *buf)
2078 {
2079 struct virtnet_info *vi = netdev_priv(queue->dev);
2080 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2081 struct ewma_pkt_len *avg;
2082
2083 BUG_ON(queue_index >= vi->max_queue_pairs);
2084 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2085 return sprintf(buf, "%u\n", get_mergeable_buf_len(avg));
2086 }
2087
2088 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2089 __ATTR_RO(mergeable_rx_buffer_size);
2090
2091 static struct attribute *virtio_net_mrg_rx_attrs[] = {
2092 &mergeable_rx_buffer_size_attribute.attr,
2093 NULL
2094 };
2095
2096 static const struct attribute_group virtio_net_mrg_rx_group = {
2097 .name = "virtio_net",
2098 .attrs = virtio_net_mrg_rx_attrs
2099 };
2100 #endif
2101
2102 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2103 unsigned int fbit,
2104 const char *fname, const char *dname)
2105 {
2106 if (!virtio_has_feature(vdev, fbit))
2107 return false;
2108
2109 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2110 fname, dname);
2111
2112 return true;
2113 }
2114
2115 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2116 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2117
2118 static bool virtnet_validate_features(struct virtio_device *vdev)
2119 {
2120 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2121 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2122 "VIRTIO_NET_F_CTRL_VQ") ||
2123 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2124 "VIRTIO_NET_F_CTRL_VQ") ||
2125 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2126 "VIRTIO_NET_F_CTRL_VQ") ||
2127 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2128 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2129 "VIRTIO_NET_F_CTRL_VQ"))) {
2130 return false;
2131 }
2132
2133 return true;
2134 }
2135
2136 #define MIN_MTU ETH_MIN_MTU
2137 #define MAX_MTU ETH_MAX_MTU
2138
2139 static int virtnet_probe(struct virtio_device *vdev)
2140 {
2141 int i, err;
2142 struct net_device *dev;
2143 struct virtnet_info *vi;
2144 u16 max_queue_pairs;
2145 int mtu;
2146
2147 if (!vdev->config->get) {
2148 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2149 __func__);
2150 return -EINVAL;
2151 }
2152
2153 if (!virtnet_validate_features(vdev))
2154 return -EINVAL;
2155
2156 /* Find if host supports multiqueue virtio_net device */
2157 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2158 struct virtio_net_config,
2159 max_virtqueue_pairs, &max_queue_pairs);
2160
2161 /* We need at least 2 queue's */
2162 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2163 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2164 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2165 max_queue_pairs = 1;
2166
2167 /* Allocate ourselves a network device with room for our info */
2168 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2169 if (!dev)
2170 return -ENOMEM;
2171
2172 /* Set up network device as normal. */
2173 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2174 dev->netdev_ops = &virtnet_netdev;
2175 dev->features = NETIF_F_HIGHDMA;
2176
2177 dev->ethtool_ops = &virtnet_ethtool_ops;
2178 SET_NETDEV_DEV(dev, &vdev->dev);
2179
2180 /* Do we support "hardware" checksums? */
2181 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2182 /* This opens up the world of extra features. */
2183 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2184 if (csum)
2185 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2186
2187 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2188 dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
2189 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2190 }
2191 /* Individual feature bits: what can host handle? */
2192 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
2193 dev->hw_features |= NETIF_F_TSO;
2194 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
2195 dev->hw_features |= NETIF_F_TSO6;
2196 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
2197 dev->hw_features |= NETIF_F_TSO_ECN;
2198 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
2199 dev->hw_features |= NETIF_F_UFO;
2200
2201 dev->features |= NETIF_F_GSO_ROBUST;
2202
2203 if (gso)
2204 dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
2205 /* (!csum && gso) case will be fixed by register_netdev() */
2206 }
2207 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
2208 dev->features |= NETIF_F_RXCSUM;
2209
2210 dev->vlan_features = dev->features;
2211
2212 /* MTU range: 68 - 65535 */
2213 dev->min_mtu = MIN_MTU;
2214 dev->max_mtu = MAX_MTU;
2215
2216 /* Configuration may specify what MAC to use. Otherwise random. */
2217 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
2218 virtio_cread_bytes(vdev,
2219 offsetof(struct virtio_net_config, mac),
2220 dev->dev_addr, dev->addr_len);
2221 else
2222 eth_hw_addr_random(dev);
2223
2224 /* Set up our device-specific information */
2225 vi = netdev_priv(dev);
2226 vi->dev = dev;
2227 vi->vdev = vdev;
2228 vdev->priv = vi;
2229 vi->stats = alloc_percpu(struct virtnet_stats);
2230 err = -ENOMEM;
2231 if (vi->stats == NULL)
2232 goto free;
2233
2234 for_each_possible_cpu(i) {
2235 struct virtnet_stats *virtnet_stats;
2236 virtnet_stats = per_cpu_ptr(vi->stats, i);
2237 u64_stats_init(&virtnet_stats->tx_syncp);
2238 u64_stats_init(&virtnet_stats->rx_syncp);
2239 }
2240
2241 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
2242
2243 /* If we can receive ANY GSO packets, we must allocate large ones. */
2244 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2245 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2246 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
2247 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
2248 vi->big_packets = true;
2249
2250 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
2251 vi->mergeable_rx_bufs = true;
2252
2253 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
2254 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2255 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2256 else
2257 vi->hdr_len = sizeof(struct virtio_net_hdr);
2258
2259 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
2260 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2261 vi->any_header_sg = true;
2262
2263 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2264 vi->has_cvq = true;
2265
2266 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2267 mtu = virtio_cread16(vdev,
2268 offsetof(struct virtio_net_config,
2269 mtu));
2270 if (mtu < dev->min_mtu) {
2271 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2272 } else {
2273 dev->mtu = mtu;
2274 dev->max_mtu = mtu;
2275 }
2276 }
2277
2278 if (vi->any_header_sg)
2279 dev->needed_headroom = vi->hdr_len;
2280
2281 /* Enable multiqueue by default */
2282 if (num_online_cpus() >= max_queue_pairs)
2283 vi->curr_queue_pairs = max_queue_pairs;
2284 else
2285 vi->curr_queue_pairs = num_online_cpus();
2286 vi->max_queue_pairs = max_queue_pairs;
2287
2288 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2289 err = init_vqs(vi);
2290 if (err)
2291 goto free_stats;
2292
2293 #ifdef CONFIG_SYSFS
2294 if (vi->mergeable_rx_bufs)
2295 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
2296 #endif
2297 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
2298 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
2299
2300 virtnet_init_settings(dev);
2301
2302 err = register_netdev(dev);
2303 if (err) {
2304 pr_debug("virtio_net: registering device failed\n");
2305 goto free_vqs;
2306 }
2307
2308 virtio_device_ready(vdev);
2309
2310 err = virtnet_cpu_notif_add(vi);
2311 if (err) {
2312 pr_debug("virtio_net: registering cpu notifier failed\n");
2313 goto free_unregister_netdev;
2314 }
2315
2316 rtnl_lock();
2317 virtnet_set_queues(vi, vi->curr_queue_pairs);
2318 rtnl_unlock();
2319
2320 /* Assume link up if device can't report link status,
2321 otherwise get link status from config. */
2322 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
2323 netif_carrier_off(dev);
2324 schedule_work(&vi->config_work);
2325 } else {
2326 vi->status = VIRTIO_NET_S_LINK_UP;
2327 netif_carrier_on(dev);
2328 }
2329
2330 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2331 dev->name, max_queue_pairs);
2332
2333 return 0;
2334
2335 free_unregister_netdev:
2336 vi->vdev->config->reset(vdev);
2337
2338 unregister_netdev(dev);
2339 free_vqs:
2340 cancel_delayed_work_sync(&vi->refill);
2341 free_receive_page_frags(vi);
2342 virtnet_del_vqs(vi);
2343 free_stats:
2344 free_percpu(vi->stats);
2345 free:
2346 free_netdev(dev);
2347 return err;
2348 }
2349
2350 static void remove_vq_common(struct virtnet_info *vi)
2351 {
2352 vi->vdev->config->reset(vi->vdev);
2353
2354 /* Free unused buffers in both send and recv, if any. */
2355 free_unused_bufs(vi);
2356
2357 free_receive_bufs(vi);
2358
2359 free_receive_page_frags(vi);
2360
2361 virtnet_del_vqs(vi);
2362 }
2363
2364 static void virtnet_remove(struct virtio_device *vdev)
2365 {
2366 struct virtnet_info *vi = vdev->priv;
2367
2368 virtnet_cpu_notif_remove(vi);
2369
2370 /* Make sure no work handler is accessing the device. */
2371 flush_work(&vi->config_work);
2372
2373 unregister_netdev(vi->dev);
2374
2375 remove_vq_common(vi);
2376
2377 free_percpu(vi->stats);
2378 free_netdev(vi->dev);
2379 }
2380
2381 #ifdef CONFIG_PM_SLEEP
2382 static int virtnet_freeze(struct virtio_device *vdev)
2383 {
2384 struct virtnet_info *vi = vdev->priv;
2385 int i;
2386
2387 virtnet_cpu_notif_remove(vi);
2388
2389 /* Make sure no work handler is accessing the device */
2390 flush_work(&vi->config_work);
2391
2392 netif_device_detach(vi->dev);
2393 cancel_delayed_work_sync(&vi->refill);
2394
2395 if (netif_running(vi->dev)) {
2396 for (i = 0; i < vi->max_queue_pairs; i++)
2397 napi_disable(&vi->rq[i].napi);
2398 }
2399
2400 remove_vq_common(vi);
2401
2402 return 0;
2403 }
2404
2405 static int virtnet_restore(struct virtio_device *vdev)
2406 {
2407 struct virtnet_info *vi = vdev->priv;
2408 int err, i;
2409
2410 err = init_vqs(vi);
2411 if (err)
2412 return err;
2413
2414 virtio_device_ready(vdev);
2415
2416 if (netif_running(vi->dev)) {
2417 for (i = 0; i < vi->curr_queue_pairs; i++)
2418 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
2419 schedule_delayed_work(&vi->refill, 0);
2420
2421 for (i = 0; i < vi->max_queue_pairs; i++)
2422 virtnet_napi_enable(&vi->rq[i]);
2423 }
2424
2425 netif_device_attach(vi->dev);
2426
2427 rtnl_lock();
2428 virtnet_set_queues(vi, vi->curr_queue_pairs);
2429 rtnl_unlock();
2430
2431 err = virtnet_cpu_notif_add(vi);
2432 if (err)
2433 return err;
2434
2435 return 0;
2436 }
2437 #endif
2438
2439 static struct virtio_device_id id_table[] = {
2440 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
2441 { 0 },
2442 };
2443
2444 #define VIRTNET_FEATURES \
2445 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2446 VIRTIO_NET_F_MAC, \
2447 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2448 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2449 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2450 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2451 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2452 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2453 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2454 VIRTIO_NET_F_MTU
2455
2456 static unsigned int features[] = {
2457 VIRTNET_FEATURES,
2458 };
2459
2460 static unsigned int features_legacy[] = {
2461 VIRTNET_FEATURES,
2462 VIRTIO_NET_F_GSO,
2463 VIRTIO_F_ANY_LAYOUT,
2464 };
2465
2466 static struct virtio_driver virtio_net_driver = {
2467 .feature_table = features,
2468 .feature_table_size = ARRAY_SIZE(features),
2469 .feature_table_legacy = features_legacy,
2470 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
2471 .driver.name = KBUILD_MODNAME,
2472 .driver.owner = THIS_MODULE,
2473 .id_table = id_table,
2474 .probe = virtnet_probe,
2475 .remove = virtnet_remove,
2476 .config_changed = virtnet_config_changed,
2477 #ifdef CONFIG_PM_SLEEP
2478 .freeze = virtnet_freeze,
2479 .restore = virtnet_restore,
2480 #endif
2481 };
2482
2483 static __init int virtio_net_driver_init(void)
2484 {
2485 int ret;
2486
2487 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
2488 virtnet_cpu_online,
2489 virtnet_cpu_down_prep);
2490 if (ret < 0)
2491 goto out;
2492 virtionet_online = ret;
2493 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
2494 NULL, virtnet_cpu_dead);
2495 if (ret)
2496 goto err_dead;
2497
2498 ret = register_virtio_driver(&virtio_net_driver);
2499 if (ret)
2500 goto err_virtio;
2501 return 0;
2502 err_virtio:
2503 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2504 err_dead:
2505 cpuhp_remove_multi_state(virtionet_online);
2506 out:
2507 return ret;
2508 }
2509 module_init(virtio_net_driver_init);
2510
2511 static __exit void virtio_net_driver_exit(void)
2512 {
2513 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2514 cpuhp_remove_multi_state(virtionet_online);
2515 unregister_virtio_driver(&virtio_net_driver);
2516 }
2517 module_exit(virtio_net_driver_exit);
2518
2519 MODULE_DEVICE_TABLE(virtio, id_table);
2520 MODULE_DESCRIPTION("Virtio network driver");
2521 MODULE_LICENSE("GPL");
Linux with added FPC-III support