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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};
65
66struct virtnet_stat_desc {
67 char desc[ETH_GSTRING_LEN];
68 size_t offset;
69};
70
71struct virtnet_sq_stats {
72 struct u64_stats_sync syncp;
73 u64 packets;
74 u64 bytes;
75 u64 xdp_tx;
76 u64 xdp_tx_drops;
77 u64 kicks;
78};
79
80struct virtnet_rq_stats {
81 struct u64_stats_sync syncp;
82 u64 packets;
83 u64 bytes;
84 u64 drops;
85 u64 xdp_packets;
86 u64 xdp_tx;
87 u64 xdp_redirects;
88 u64 xdp_drops;
89 u64 kicks;
90};
91
92#define VIRTNET_SQ_STAT(m) offsetof(struct virtnet_sq_stats, m)
93#define VIRTNET_RQ_STAT(m) offsetof(struct virtnet_rq_stats, m)
94
95static const struct virtnet_stat_desc virtnet_sq_stats_desc[] = {
96 { "packets", VIRTNET_SQ_STAT(packets) },
97 { "bytes", VIRTNET_SQ_STAT(bytes) },
98 { "xdp_tx", VIRTNET_SQ_STAT(xdp_tx) },
99 { "xdp_tx_drops", VIRTNET_SQ_STAT(xdp_tx_drops) },
100 { "kicks", VIRTNET_SQ_STAT(kicks) },
101};
102
103static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = {
104 { "packets", VIRTNET_RQ_STAT(packets) },
105 { "bytes", VIRTNET_RQ_STAT(bytes) },
106 { "drops", VIRTNET_RQ_STAT(drops) },
107 { "xdp_packets", VIRTNET_RQ_STAT(xdp_packets) },
108 { "xdp_tx", VIRTNET_RQ_STAT(xdp_tx) },
109 { "xdp_redirects", VIRTNET_RQ_STAT(xdp_redirects) },
110 { "xdp_drops", VIRTNET_RQ_STAT(xdp_drops) },
111 { "kicks", VIRTNET_RQ_STAT(kicks) },
112};
113
114#define VIRTNET_SQ_STATS_LEN ARRAY_SIZE(virtnet_sq_stats_desc)
115#define VIRTNET_RQ_STATS_LEN ARRAY_SIZE(virtnet_rq_stats_desc)
116
117/* Internal representation of a send virtqueue */
118struct send_queue {
119 /* Virtqueue associated with this send _queue */
120 struct virtqueue *vq;
121
122 /* TX: fragments + linear part + virtio header */
123 struct scatterlist sg[MAX_SKB_FRAGS + 2];
124
125 /* Name of the send queue: output.$index */
126 char name[40];
127
128 struct virtnet_sq_stats stats;
129
130 struct napi_struct napi;
131};
132
133/* Internal representation of a receive virtqueue */
134struct receive_queue {
135 /* Virtqueue associated with this receive_queue */
136 struct virtqueue *vq;
137
138 struct napi_struct napi;
139
140 struct bpf_prog __rcu *xdp_prog;
141
142 struct virtnet_rq_stats stats;
143
144 /* Chain pages by the private ptr. */
145 struct page *pages;
146
147 /* Average packet length for mergeable receive buffers. */
148 struct ewma_pkt_len mrg_avg_pkt_len;
149
150 /* Page frag for packet buffer allocation. */
151 struct page_frag alloc_frag;
152
153 /* RX: fragments + linear part + virtio header */
154 struct scatterlist sg[MAX_SKB_FRAGS + 2];
155
156 /* Min single buffer size for mergeable buffers case. */
157 unsigned int min_buf_len;
158
159 /* Name of this receive queue: input.$index */
160 char name[40];
161
162 struct xdp_rxq_info xdp_rxq;
163};
164
165/* Control VQ buffers: protected by the rtnl lock */
166struct control_buf {
167 struct virtio_net_ctrl_hdr hdr;
168 virtio_net_ctrl_ack status;
169 struct virtio_net_ctrl_mq mq;
170 u8 promisc;
171 u8 allmulti;
172 __virtio16 vid;
173 __virtio64 offloads;
174};
175
176struct virtnet_info {
177 struct virtio_device *vdev;
178 struct virtqueue *cvq;
179 struct net_device *dev;
180 struct send_queue *sq;
181 struct receive_queue *rq;
182 unsigned int status;
183
184 /* Max # of queue pairs supported by the device */
185 u16 max_queue_pairs;
186
187 /* # of queue pairs currently used by the driver */
188 u16 curr_queue_pairs;
189
190 /* # of XDP queue pairs currently used by the driver */
191 u16 xdp_queue_pairs;
192
193 /* I like... big packets and I cannot lie! */
194 bool big_packets;
195
196 /* Host will merge rx buffers for big packets (shake it! shake it!) */
197 bool mergeable_rx_bufs;
198
199 /* Has control virtqueue */
200 bool has_cvq;
201
202 /* Host can handle any s/g split between our header and packet data */
203 bool any_header_sg;
204
205 /* Packet virtio header size */
206 u8 hdr_len;
207
208 /* Work struct for refilling if we run low on memory. */
209 struct delayed_work refill;
210
211 /* Work struct for config space updates */
212 struct work_struct config_work;
213
214 /* Does the affinity hint is set for virtqueues? */
215 bool affinity_hint_set;
216
217 /* CPU hotplug instances for online & dead */
218 struct hlist_node node;
219 struct hlist_node node_dead;
220
221 struct control_buf *ctrl;
222
223 /* Ethtool settings */
224 u8 duplex;
225 u32 speed;
226
227 unsigned long guest_offloads;
228 unsigned long guest_offloads_capable;
229
230 /* failover when STANDBY feature enabled */
231 struct failover *failover;
232};
233
234struct padded_vnet_hdr {
235 struct virtio_net_hdr_mrg_rxbuf hdr;
236 /*
237 * hdr is in a separate sg buffer, and data sg buffer shares same page
238 * with this header sg. This padding makes next sg 16 byte aligned
239 * after the header.
240 */
241 char padding[4];
242};
243
244static bool is_xdp_frame(void *ptr)
245{
246 return (unsigned long)ptr & VIRTIO_XDP_FLAG;
247}
248
249static void *xdp_to_ptr(struct xdp_frame *ptr)
250{
251 return (void *)((unsigned long)ptr | VIRTIO_XDP_FLAG);
252}
253
254static struct xdp_frame *ptr_to_xdp(void *ptr)
255{
256 return (struct xdp_frame *)((unsigned long)ptr & ~VIRTIO_XDP_FLAG);
257}
258
259/* Converting between virtqueue no. and kernel tx/rx queue no.
260 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
261 */
262static int vq2txq(struct virtqueue *vq)
263{
264 return (vq->index - 1) / 2;
265}
266
267static int txq2vq(int txq)
268{
269 return txq * 2 + 1;
270}
271
272static int vq2rxq(struct virtqueue *vq)
273{
274 return vq->index / 2;
275}
276
277static int rxq2vq(int rxq)
278{
279 return rxq * 2;
280}
281
282static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
283{
284 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
285}
286
287/*
288 * private is used to chain pages for big packets, put the whole
289 * most recent used list in the beginning for reuse
290 */
291static void give_pages(struct receive_queue *rq, struct page *page)
292{
293 struct page *end;
294
295 /* Find end of list, sew whole thing into vi->rq.pages. */
296 for (end = page; end->private; end = (struct page *)end->private);
297 end->private = (unsigned long)rq->pages;
298 rq->pages = page;
299}
300
301static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
302{
303 struct page *p = rq->pages;
304
305 if (p) {
306 rq->pages = (struct page *)p->private;
307 /* clear private here, it is used to chain pages */
308 p->private = 0;
309 } else
310 p = alloc_page(gfp_mask);
311 return p;
312}
313
314static void virtqueue_napi_schedule(struct napi_struct *napi,
315 struct virtqueue *vq)
316{
317 if (napi_schedule_prep(napi)) {
318 virtqueue_disable_cb(vq);
319 __napi_schedule(napi);
320 }
321}
322
323static void virtqueue_napi_complete(struct napi_struct *napi,
324 struct virtqueue *vq, int processed)
325{
326 int opaque;
327
328 opaque = virtqueue_enable_cb_prepare(vq);
329 if (napi_complete_done(napi, processed)) {
330 if (unlikely(virtqueue_poll(vq, opaque)))
331 virtqueue_napi_schedule(napi, vq);
332 } else {
333 virtqueue_disable_cb(vq);
334 }
335}
336
337static void skb_xmit_done(struct virtqueue *vq)
338{
339 struct virtnet_info *vi = vq->vdev->priv;
340 struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
341
342 /* Suppress further interrupts. */
343 virtqueue_disable_cb(vq);
344
345 if (napi->weight)
346 virtqueue_napi_schedule(napi, vq);
347 else
348 /* We were probably waiting for more output buffers. */
349 netif_wake_subqueue(vi->dev, vq2txq(vq));
350}
351
352#define MRG_CTX_HEADER_SHIFT 22
353static void *mergeable_len_to_ctx(unsigned int truesize,
354 unsigned int headroom)
355{
356 return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize);
357}
358
359static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
360{
361 return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
362}
363
364static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
365{
366 return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
367}
368
369/* Called from bottom half context */
370static struct sk_buff *page_to_skb(struct virtnet_info *vi,
371 struct receive_queue *rq,
372 struct page *page, unsigned int offset,
373 unsigned int len, unsigned int truesize,
374 bool hdr_valid)
375{
376 struct sk_buff *skb;
377 struct virtio_net_hdr_mrg_rxbuf *hdr;
378 unsigned int copy, hdr_len, hdr_padded_len;
379 char *p;
380
381 p = page_address(page) + offset;
382
383 /* copy small packet so we can reuse these pages for small data */
384 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
385 if (unlikely(!skb))
386 return NULL;
387
388 hdr = skb_vnet_hdr(skb);
389
390 hdr_len = vi->hdr_len;
391 if (vi->mergeable_rx_bufs)
392 hdr_padded_len = sizeof(*hdr);
393 else
394 hdr_padded_len = sizeof(struct padded_vnet_hdr);
395
396 if (hdr_valid)
397 memcpy(hdr, p, hdr_len);
398
399 len -= hdr_len;
400 offset += hdr_padded_len;
401 p += hdr_padded_len;
402
403 copy = len;
404 if (copy > skb_tailroom(skb))
405 copy = skb_tailroom(skb);
406 skb_put_data(skb, p, copy);
407
408 len -= copy;
409 offset += copy;
410
411 if (vi->mergeable_rx_bufs) {
412 if (len)
413 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
414 else
415 put_page(page);
416 return skb;
417 }
418
419 /*
420 * Verify that we can indeed put this data into a skb.
421 * This is here to handle cases when the device erroneously
422 * tries to receive more than is possible. This is usually
423 * the case of a broken device.
424 */
425 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
426 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
427 dev_kfree_skb(skb);
428 return NULL;
429 }
430 BUG_ON(offset >= PAGE_SIZE);
431 while (len) {
432 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
433 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
434 frag_size, truesize);
435 len -= frag_size;
436 page = (struct page *)page->private;
437 offset = 0;
438 }
439
440 if (page)
441 give_pages(rq, page);
442
443 return skb;
444}
445
446static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
447 struct send_queue *sq,
448 struct xdp_frame *xdpf)
449{
450 struct virtio_net_hdr_mrg_rxbuf *hdr;
451 int err;
452
453 /* virtqueue want to use data area in-front of packet */
454 if (unlikely(xdpf->metasize > 0))
455 return -EOPNOTSUPP;
456
457 if (unlikely(xdpf->headroom < vi->hdr_len))
458 return -EOVERFLOW;
459
460 /* Make room for virtqueue hdr (also change xdpf->headroom?) */
461 xdpf->data -= vi->hdr_len;
462 /* Zero header and leave csum up to XDP layers */
463 hdr = xdpf->data;
464 memset(hdr, 0, vi->hdr_len);
465 xdpf->len += vi->hdr_len;
466
467 sg_init_one(sq->sg, xdpf->data, xdpf->len);
468
469 err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp_to_ptr(xdpf),
470 GFP_ATOMIC);
471 if (unlikely(err))
472 return -ENOSPC; /* Caller handle free/refcnt */
473
474 return 0;
475}
476
477static struct send_queue *virtnet_xdp_sq(struct virtnet_info *vi)
478{
479 unsigned int qp;
480
481 qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
482 return &vi->sq[qp];
483}
484
485static int virtnet_xdp_xmit(struct net_device *dev,
486 int n, struct xdp_frame **frames, u32 flags)
487{
488 struct virtnet_info *vi = netdev_priv(dev);
489 struct receive_queue *rq = vi->rq;
490 struct bpf_prog *xdp_prog;
491 struct send_queue *sq;
492 unsigned int len;
493 int packets = 0;
494 int bytes = 0;
495 int drops = 0;
496 int kicks = 0;
497 int ret, err;
498 void *ptr;
499 int i;
500
501 /* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this
502 * indicate XDP resources have been successfully allocated.
503 */
504 xdp_prog = rcu_dereference(rq->xdp_prog);
505 if (!xdp_prog)
506 return -ENXIO;
507
508 sq = virtnet_xdp_sq(vi);
509
510 if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
511 ret = -EINVAL;
512 drops = n;
513 goto out;
514 }
515
516 /* Free up any pending old buffers before queueing new ones. */
517 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
518 if (likely(is_xdp_frame(ptr))) {
519 struct xdp_frame *frame = ptr_to_xdp(ptr);
520
521 bytes += frame->len;
522 xdp_return_frame(frame);
523 } else {
524 struct sk_buff *skb = ptr;
525
526 bytes += skb->len;
527 napi_consume_skb(skb, false);
528 }
529 packets++;
530 }
531
532 for (i = 0; i < n; i++) {
533 struct xdp_frame *xdpf = frames[i];
534
535 err = __virtnet_xdp_xmit_one(vi, sq, xdpf);
536 if (err) {
537 xdp_return_frame_rx_napi(xdpf);
538 drops++;
539 }
540 }
541 ret = n - drops;
542
543 if (flags & XDP_XMIT_FLUSH) {
544 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
545 kicks = 1;
546 }
547out:
548 u64_stats_update_begin(&sq->stats.syncp);
549 sq->stats.bytes += bytes;
550 sq->stats.packets += packets;
551 sq->stats.xdp_tx += n;
552 sq->stats.xdp_tx_drops += drops;
553 sq->stats.kicks += kicks;
554 u64_stats_update_end(&sq->stats.syncp);
555
556 return ret;
557}
558
559static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
560{
561 return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
562}
563
564/* We copy the packet for XDP in the following cases:
565 *
566 * 1) Packet is scattered across multiple rx buffers.
567 * 2) Headroom space is insufficient.
568 *
569 * This is inefficient but it's a temporary condition that
570 * we hit right after XDP is enabled and until queue is refilled
571 * with large buffers with sufficient headroom - so it should affect
572 * at most queue size packets.
573 * Afterwards, the conditions to enable
574 * XDP should preclude the underlying device from sending packets
575 * across multiple buffers (num_buf > 1), and we make sure buffers
576 * have enough headroom.
577 */
578static struct page *xdp_linearize_page(struct receive_queue *rq,
579 u16 *num_buf,
580 struct page *p,
581 int offset,
582 int page_off,
583 unsigned int *len)
584{
585 struct page *page = alloc_page(GFP_ATOMIC);
586
587 if (!page)
588 return NULL;
589
590 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
591 page_off += *len;
592
593 while (--*num_buf) {
594 int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
595 unsigned int buflen;
596 void *buf;
597 int off;
598
599 buf = virtqueue_get_buf(rq->vq, &buflen);
600 if (unlikely(!buf))
601 goto err_buf;
602
603 p = virt_to_head_page(buf);
604 off = buf - page_address(p);
605
606 /* guard against a misconfigured or uncooperative backend that
607 * is sending packet larger than the MTU.
608 */
609 if ((page_off + buflen + tailroom) > PAGE_SIZE) {
610 put_page(p);
611 goto err_buf;
612 }
613
614 memcpy(page_address(page) + page_off,
615 page_address(p) + off, buflen);
616 page_off += buflen;
617 put_page(p);
618 }
619
620 /* Headroom does not contribute to packet length */
621 *len = page_off - VIRTIO_XDP_HEADROOM;
622 return page;
623err_buf:
624 __free_pages(page, 0);
625 return NULL;
626}
627
628static struct sk_buff *receive_small(struct net_device *dev,
629 struct virtnet_info *vi,
630 struct receive_queue *rq,
631 void *buf, void *ctx,
632 unsigned int len,
633 unsigned int *xdp_xmit,
634 struct virtnet_rq_stats *stats)
635{
636 struct sk_buff *skb;
637 struct bpf_prog *xdp_prog;
638 unsigned int xdp_headroom = (unsigned long)ctx;
639 unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
640 unsigned int headroom = vi->hdr_len + header_offset;
641 unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
642 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
643 struct page *page = virt_to_head_page(buf);
644 unsigned int delta = 0;
645 struct page *xdp_page;
646 int err;
647
648 len -= vi->hdr_len;
649 stats->bytes += len;
650
651 rcu_read_lock();
652 xdp_prog = rcu_dereference(rq->xdp_prog);
653 if (xdp_prog) {
654 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
655 struct xdp_frame *xdpf;
656 struct xdp_buff xdp;
657 void *orig_data;
658 u32 act;
659
660 if (unlikely(hdr->hdr.gso_type))
661 goto err_xdp;
662
663 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
664 int offset = buf - page_address(page) + header_offset;
665 unsigned int tlen = len + vi->hdr_len;
666 u16 num_buf = 1;
667
668 xdp_headroom = virtnet_get_headroom(vi);
669 header_offset = VIRTNET_RX_PAD + xdp_headroom;
670 headroom = vi->hdr_len + header_offset;
671 buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
672 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
673 xdp_page = xdp_linearize_page(rq, &num_buf, page,
674 offset, header_offset,
675 &tlen);
676 if (!xdp_page)
677 goto err_xdp;
678
679 buf = page_address(xdp_page);
680 put_page(page);
681 page = xdp_page;
682 }
683
684 xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
685 xdp.data = xdp.data_hard_start + xdp_headroom;
686 xdp_set_data_meta_invalid(&xdp);
687 xdp.data_end = xdp.data + len;
688 xdp.rxq = &rq->xdp_rxq;
689 orig_data = xdp.data;
690 act = bpf_prog_run_xdp(xdp_prog, &xdp);
691 stats->xdp_packets++;
692
693 switch (act) {
694 case XDP_PASS:
695 /* Recalculate length in case bpf program changed it */
696 delta = orig_data - xdp.data;
697 len = xdp.data_end - xdp.data;
698 break;
699 case XDP_TX:
700 stats->xdp_tx++;
701 xdpf = convert_to_xdp_frame(&xdp);
702 if (unlikely(!xdpf))
703 goto err_xdp;
704 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
705 if (unlikely(err < 0)) {
706 trace_xdp_exception(vi->dev, xdp_prog, act);
707 goto err_xdp;
708 }
709 *xdp_xmit |= VIRTIO_XDP_TX;
710 rcu_read_unlock();
711 goto xdp_xmit;
712 case XDP_REDIRECT:
713 stats->xdp_redirects++;
714 err = xdp_do_redirect(dev, &xdp, xdp_prog);
715 if (err)
716 goto err_xdp;
717 *xdp_xmit |= VIRTIO_XDP_REDIR;
718 rcu_read_unlock();
719 goto xdp_xmit;
720 default:
721 bpf_warn_invalid_xdp_action(act);
722 /* fall through */
723 case XDP_ABORTED:
724 trace_xdp_exception(vi->dev, xdp_prog, act);
725 case XDP_DROP:
726 goto err_xdp;
727 }
728 }
729 rcu_read_unlock();
730
731 skb = build_skb(buf, buflen);
732 if (!skb) {
733 put_page(page);
734 goto err;
735 }
736 skb_reserve(skb, headroom - delta);
737 skb_put(skb, len);
738 if (!delta) {
739 buf += header_offset;
740 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
741 } /* keep zeroed vnet hdr since packet was changed by bpf */
742
743err:
744 return skb;
745
746err_xdp:
747 rcu_read_unlock();
748 stats->xdp_drops++;
749 stats->drops++;
750 put_page(page);
751xdp_xmit:
752 return NULL;
753}
754
755static struct sk_buff *receive_big(struct net_device *dev,
756 struct virtnet_info *vi,
757 struct receive_queue *rq,
758 void *buf,
759 unsigned int len,
760 struct virtnet_rq_stats *stats)
761{
762 struct page *page = buf;
763 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len,
764 PAGE_SIZE, true);
765
766 stats->bytes += len - vi->hdr_len;
767 if (unlikely(!skb))
768 goto err;
769
770 return skb;
771
772err:
773 stats->drops++;
774 give_pages(rq, page);
775 return NULL;
776}
777
778static struct sk_buff *receive_mergeable(struct net_device *dev,
779 struct virtnet_info *vi,
780 struct receive_queue *rq,
781 void *buf,
782 void *ctx,
783 unsigned int len,
784 unsigned int *xdp_xmit,
785 struct virtnet_rq_stats *stats)
786{
787 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
788 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
789 struct page *page = virt_to_head_page(buf);
790 int offset = buf - page_address(page);
791 struct sk_buff *head_skb, *curr_skb;
792 struct bpf_prog *xdp_prog;
793 unsigned int truesize;
794 unsigned int headroom = mergeable_ctx_to_headroom(ctx);
795 int err;
796
797 head_skb = NULL;
798 stats->bytes += len - vi->hdr_len;
799
800 rcu_read_lock();
801 xdp_prog = rcu_dereference(rq->xdp_prog);
802 if (xdp_prog) {
803 struct xdp_frame *xdpf;
804 struct page *xdp_page;
805 struct xdp_buff xdp;
806 void *data;
807 u32 act;
808
809 /* Transient failure which in theory could occur if
810 * in-flight packets from before XDP was enabled reach
811 * the receive path after XDP is loaded.
812 */
813 if (unlikely(hdr->hdr.gso_type))
814 goto err_xdp;
815
816 /* This happens when rx buffer size is underestimated
817 * or headroom is not enough because of the buffer
818 * was refilled before XDP is set. This should only
819 * happen for the first several packets, so we don't
820 * care much about its performance.
821 */
822 if (unlikely(num_buf > 1 ||
823 headroom < virtnet_get_headroom(vi))) {
824 /* linearize data for XDP */
825 xdp_page = xdp_linearize_page(rq, &num_buf,
826 page, offset,
827 VIRTIO_XDP_HEADROOM,
828 &len);
829 if (!xdp_page)
830 goto err_xdp;
831 offset = VIRTIO_XDP_HEADROOM;
832 } else {
833 xdp_page = page;
834 }
835
836 /* Allow consuming headroom but reserve enough space to push
837 * the descriptor on if we get an XDP_TX return code.
838 */
839 data = page_address(xdp_page) + offset;
840 xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
841 xdp.data = data + vi->hdr_len;
842 xdp_set_data_meta_invalid(&xdp);
843 xdp.data_end = xdp.data + (len - vi->hdr_len);
844 xdp.rxq = &rq->xdp_rxq;
845
846 act = bpf_prog_run_xdp(xdp_prog, &xdp);
847 stats->xdp_packets++;
848
849 switch (act) {
850 case XDP_PASS:
851 /* recalculate offset to account for any header
852 * adjustments. Note other cases do not build an
853 * skb and avoid using offset
854 */
855 offset = xdp.data -
856 page_address(xdp_page) - vi->hdr_len;
857
858 /* recalculate len if xdp.data or xdp.data_end were
859 * adjusted
860 */
861 len = xdp.data_end - xdp.data + vi->hdr_len;
862 /* We can only create skb based on xdp_page. */
863 if (unlikely(xdp_page != page)) {
864 rcu_read_unlock();
865 put_page(page);
866 head_skb = page_to_skb(vi, rq, xdp_page,
867 offset, len,
868 PAGE_SIZE, false);
869 return head_skb;
870 }
871 break;
872 case XDP_TX:
873 stats->xdp_tx++;
874 xdpf = convert_to_xdp_frame(&xdp);
875 if (unlikely(!xdpf))
876 goto err_xdp;
877 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
878 if (unlikely(err < 0)) {
879 trace_xdp_exception(vi->dev, xdp_prog, act);
880 if (unlikely(xdp_page != page))
881 put_page(xdp_page);
882 goto err_xdp;
883 }
884 *xdp_xmit |= VIRTIO_XDP_TX;
885 if (unlikely(xdp_page != page))
886 put_page(page);
887 rcu_read_unlock();
888 goto xdp_xmit;
889 case XDP_REDIRECT:
890 stats->xdp_redirects++;
891 err = xdp_do_redirect(dev, &xdp, xdp_prog);
892 if (err) {
893 if (unlikely(xdp_page != page))
894 put_page(xdp_page);
895 goto err_xdp;
896 }
897 *xdp_xmit |= VIRTIO_XDP_REDIR;
898 if (unlikely(xdp_page != page))
899 put_page(page);
900 rcu_read_unlock();
901 goto xdp_xmit;
902 default:
903 bpf_warn_invalid_xdp_action(act);
904 /* fall through */
905 case XDP_ABORTED:
906 trace_xdp_exception(vi->dev, xdp_prog, act);
907 /* fall through */
908 case XDP_DROP:
909 if (unlikely(xdp_page != page))
910 __free_pages(xdp_page, 0);
911 goto err_xdp;
912 }
913 }
914 rcu_read_unlock();
915
916 truesize = mergeable_ctx_to_truesize(ctx);
917 if (unlikely(len > truesize)) {
918 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
919 dev->name, len, (unsigned long)ctx);
920 dev->stats.rx_length_errors++;
921 goto err_skb;
922 }
923
924 head_skb = page_to_skb(vi, rq, page, offset, len, truesize, !xdp_prog);
925 curr_skb = head_skb;
926
927 if (unlikely(!curr_skb))
928 goto err_skb;
929 while (--num_buf) {
930 int num_skb_frags;
931
932 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
933 if (unlikely(!buf)) {
934 pr_debug("%s: rx error: %d buffers out of %d missing\n",
935 dev->name, num_buf,
936 virtio16_to_cpu(vi->vdev,
937 hdr->num_buffers));
938 dev->stats.rx_length_errors++;
939 goto err_buf;
940 }
941
942 stats->bytes += len;
943 page = virt_to_head_page(buf);
944
945 truesize = mergeable_ctx_to_truesize(ctx);
946 if (unlikely(len > truesize)) {
947 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
948 dev->name, len, (unsigned long)ctx);
949 dev->stats.rx_length_errors++;
950 goto err_skb;
951 }
952
953 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
954 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
955 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
956
957 if (unlikely(!nskb))
958 goto err_skb;
959 if (curr_skb == head_skb)
960 skb_shinfo(curr_skb)->frag_list = nskb;
961 else
962 curr_skb->next = nskb;
963 curr_skb = nskb;
964 head_skb->truesize += nskb->truesize;
965 num_skb_frags = 0;
966 }
967 if (curr_skb != head_skb) {
968 head_skb->data_len += len;
969 head_skb->len += len;
970 head_skb->truesize += truesize;
971 }
972 offset = buf - page_address(page);
973 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
974 put_page(page);
975 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
976 len, truesize);
977 } else {
978 skb_add_rx_frag(curr_skb, num_skb_frags, page,
979 offset, len, truesize);
980 }
981 }
982
983 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
984 return head_skb;
985
986err_xdp:
987 rcu_read_unlock();
988 stats->xdp_drops++;
989err_skb:
990 put_page(page);
991 while (num_buf-- > 1) {
992 buf = virtqueue_get_buf(rq->vq, &len);
993 if (unlikely(!buf)) {
994 pr_debug("%s: rx error: %d buffers missing\n",
995 dev->name, num_buf);
996 dev->stats.rx_length_errors++;
997 break;
998 }
999 stats->bytes += len;
1000 page = virt_to_head_page(buf);
1001 put_page(page);
1002 }
1003err_buf:
1004 stats->drops++;
1005 dev_kfree_skb(head_skb);
1006xdp_xmit:
1007 return NULL;
1008}
1009
1010static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
1011 void *buf, unsigned int len, void **ctx,
1012 unsigned int *xdp_xmit,
1013 struct virtnet_rq_stats *stats)
1014{
1015 struct net_device *dev = vi->dev;
1016 struct sk_buff *skb;
1017 struct virtio_net_hdr_mrg_rxbuf *hdr;
1018
1019 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
1020 pr_debug("%s: short packet %i\n", dev->name, len);
1021 dev->stats.rx_length_errors++;
1022 if (vi->mergeable_rx_bufs) {
1023 put_page(virt_to_head_page(buf));
1024 } else if (vi->big_packets) {
1025 give_pages(rq, buf);
1026 } else {
1027 put_page(virt_to_head_page(buf));
1028 }
1029 return;
1030 }
1031
1032 if (vi->mergeable_rx_bufs)
1033 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit,
1034 stats);
1035 else if (vi->big_packets)
1036 skb = receive_big(dev, vi, rq, buf, len, stats);
1037 else
1038 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats);
1039
1040 if (unlikely(!skb))
1041 return;
1042
1043 hdr = skb_vnet_hdr(skb);
1044
1045 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
1046 skb->ip_summed = CHECKSUM_UNNECESSARY;
1047
1048 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
1049 virtio_is_little_endian(vi->vdev))) {
1050 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
1051 dev->name, hdr->hdr.gso_type,
1052 hdr->hdr.gso_size);
1053 goto frame_err;
1054 }
1055
1056 skb_record_rx_queue(skb, vq2rxq(rq->vq));
1057 skb->protocol = eth_type_trans(skb, dev);
1058 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
1059 ntohs(skb->protocol), skb->len, skb->pkt_type);
1060
1061 napi_gro_receive(&rq->napi, skb);
1062 return;
1063
1064frame_err:
1065 dev->stats.rx_frame_errors++;
1066 dev_kfree_skb(skb);
1067}
1068
1069/* Unlike mergeable buffers, all buffers are allocated to the
1070 * same size, except for the headroom. For this reason we do
1071 * not need to use mergeable_len_to_ctx here - it is enough
1072 * to store the headroom as the context ignoring the truesize.
1073 */
1074static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
1075 gfp_t gfp)
1076{
1077 struct page_frag *alloc_frag = &rq->alloc_frag;
1078 char *buf;
1079 unsigned int xdp_headroom = virtnet_get_headroom(vi);
1080 void *ctx = (void *)(unsigned long)xdp_headroom;
1081 int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
1082 int err;
1083
1084 len = SKB_DATA_ALIGN(len) +
1085 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
1086 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
1087 return -ENOMEM;
1088
1089 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1090 get_page(alloc_frag->page);
1091 alloc_frag->offset += len;
1092 sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
1093 vi->hdr_len + GOOD_PACKET_LEN);
1094 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1095 if (err < 0)
1096 put_page(virt_to_head_page(buf));
1097 return err;
1098}
1099
1100static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
1101 gfp_t gfp)
1102{
1103 struct page *first, *list = NULL;
1104 char *p;
1105 int i, err, offset;
1106
1107 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
1108
1109 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
1110 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
1111 first = get_a_page(rq, gfp);
1112 if (!first) {
1113 if (list)
1114 give_pages(rq, list);
1115 return -ENOMEM;
1116 }
1117 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
1118
1119 /* chain new page in list head to match sg */
1120 first->private = (unsigned long)list;
1121 list = first;
1122 }
1123
1124 first = get_a_page(rq, gfp);
1125 if (!first) {
1126 give_pages(rq, list);
1127 return -ENOMEM;
1128 }
1129 p = page_address(first);
1130
1131 /* rq->sg[0], rq->sg[1] share the same page */
1132 /* a separated rq->sg[0] for header - required in case !any_header_sg */
1133 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
1134
1135 /* rq->sg[1] for data packet, from offset */
1136 offset = sizeof(struct padded_vnet_hdr);
1137 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
1138
1139 /* chain first in list head */
1140 first->private = (unsigned long)list;
1141 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
1142 first, gfp);
1143 if (err < 0)
1144 give_pages(rq, first);
1145
1146 return err;
1147}
1148
1149static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
1150 struct ewma_pkt_len *avg_pkt_len,
1151 unsigned int room)
1152{
1153 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
1154 unsigned int len;
1155
1156 if (room)
1157 return PAGE_SIZE - room;
1158
1159 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
1160 rq->min_buf_len, PAGE_SIZE - hdr_len);
1161
1162 return ALIGN(len, L1_CACHE_BYTES);
1163}
1164
1165static int add_recvbuf_mergeable(struct virtnet_info *vi,
1166 struct receive_queue *rq, gfp_t gfp)
1167{
1168 struct page_frag *alloc_frag = &rq->alloc_frag;
1169 unsigned int headroom = virtnet_get_headroom(vi);
1170 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1171 unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
1172 char *buf;
1173 void *ctx;
1174 int err;
1175 unsigned int len, hole;
1176
1177 /* Extra tailroom is needed to satisfy XDP's assumption. This
1178 * means rx frags coalescing won't work, but consider we've
1179 * disabled GSO for XDP, it won't be a big issue.
1180 */
1181 len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room);
1182 if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp)))
1183 return -ENOMEM;
1184
1185 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1186 buf += headroom; /* advance address leaving hole at front of pkt */
1187 get_page(alloc_frag->page);
1188 alloc_frag->offset += len + room;
1189 hole = alloc_frag->size - alloc_frag->offset;
1190 if (hole < len + room) {
1191 /* To avoid internal fragmentation, if there is very likely not
1192 * enough space for another buffer, add the remaining space to
1193 * the current buffer.
1194 */
1195 len += hole;
1196 alloc_frag->offset += hole;
1197 }
1198
1199 sg_init_one(rq->sg, buf, len);
1200 ctx = mergeable_len_to_ctx(len, headroom);
1201 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1202 if (err < 0)
1203 put_page(virt_to_head_page(buf));
1204
1205 return err;
1206}
1207
1208/*
1209 * Returns false if we couldn't fill entirely (OOM).
1210 *
1211 * Normally run in the receive path, but can also be run from ndo_open
1212 * before we're receiving packets, or from refill_work which is
1213 * careful to disable receiving (using napi_disable).
1214 */
1215static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
1216 gfp_t gfp)
1217{
1218 int err;
1219 bool oom;
1220
1221 do {
1222 if (vi->mergeable_rx_bufs)
1223 err = add_recvbuf_mergeable(vi, rq, gfp);
1224 else if (vi->big_packets)
1225 err = add_recvbuf_big(vi, rq, gfp);
1226 else
1227 err = add_recvbuf_small(vi, rq, gfp);
1228
1229 oom = err == -ENOMEM;
1230 if (err)
1231 break;
1232 } while (rq->vq->num_free);
1233 if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
1234 u64_stats_update_begin(&rq->stats.syncp);
1235 rq->stats.kicks++;
1236 u64_stats_update_end(&rq->stats.syncp);
1237 }
1238
1239 return !oom;
1240}
1241
1242static void skb_recv_done(struct virtqueue *rvq)
1243{
1244 struct virtnet_info *vi = rvq->vdev->priv;
1245 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
1246
1247 virtqueue_napi_schedule(&rq->napi, rvq);
1248}
1249
1250static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
1251{
1252 napi_enable(napi);
1253
1254 /* If all buffers were filled by other side before we napi_enabled, we
1255 * won't get another interrupt, so process any outstanding packets now.
1256 * Call local_bh_enable after to trigger softIRQ processing.
1257 */
1258 local_bh_disable();
1259 virtqueue_napi_schedule(napi, vq);
1260 local_bh_enable();
1261}
1262
1263static void virtnet_napi_tx_enable(struct virtnet_info *vi,
1264 struct virtqueue *vq,
1265 struct napi_struct *napi)
1266{
1267 if (!napi->weight)
1268 return;
1269
1270 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1271 * enable the feature if this is likely affine with the transmit path.
1272 */
1273 if (!vi->affinity_hint_set) {
1274 napi->weight = 0;
1275 return;
1276 }
1277
1278 return virtnet_napi_enable(vq, napi);
1279}
1280
1281static void virtnet_napi_tx_disable(struct napi_struct *napi)
1282{
1283 if (napi->weight)
1284 napi_disable(napi);
1285}
1286
1287static void refill_work(struct work_struct *work)
1288{
1289 struct virtnet_info *vi =
1290 container_of(work, struct virtnet_info, refill.work);
1291 bool still_empty;
1292 int i;
1293
1294 for (i = 0; i < vi->curr_queue_pairs; i++) {
1295 struct receive_queue *rq = &vi->rq[i];
1296
1297 napi_disable(&rq->napi);
1298 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1299 virtnet_napi_enable(rq->vq, &rq->napi);
1300
1301 /* In theory, this can happen: if we don't get any buffers in
1302 * we will *never* try to fill again.
1303 */
1304 if (still_empty)
1305 schedule_delayed_work(&vi->refill, HZ/2);
1306 }
1307}
1308
1309static int virtnet_receive(struct receive_queue *rq, int budget,
1310 unsigned int *xdp_xmit)
1311{
1312 struct virtnet_info *vi = rq->vq->vdev->priv;
1313 struct virtnet_rq_stats stats = {};
1314 unsigned int len;
1315 void *buf;
1316 int i;
1317
1318 if (!vi->big_packets || vi->mergeable_rx_bufs) {
1319 void *ctx;
1320
1321 while (stats.packets < budget &&
1322 (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1323 receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats);
1324 stats.packets++;
1325 }
1326 } else {
1327 while (stats.packets < budget &&
1328 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1329 receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats);
1330 stats.packets++;
1331 }
1332 }
1333
1334 if (rq->vq->num_free > min((unsigned int)budget, virtqueue_get_vring_size(rq->vq)) / 2) {
1335 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
1336 schedule_delayed_work(&vi->refill, 0);
1337 }
1338
1339 u64_stats_update_begin(&rq->stats.syncp);
1340 for (i = 0; i < VIRTNET_RQ_STATS_LEN; i++) {
1341 size_t offset = virtnet_rq_stats_desc[i].offset;
1342 u64 *item;
1343
1344 item = (u64 *)((u8 *)&rq->stats + offset);
1345 *item += *(u64 *)((u8 *)&stats + offset);
1346 }
1347 u64_stats_update_end(&rq->stats.syncp);
1348
1349 return stats.packets;
1350}
1351
1352static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi)
1353{
1354 unsigned int len;
1355 unsigned int packets = 0;
1356 unsigned int bytes = 0;
1357 void *ptr;
1358
1359 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1360 if (likely(!is_xdp_frame(ptr))) {
1361 struct sk_buff *skb = ptr;
1362
1363 pr_debug("Sent skb %p\n", skb);
1364
1365 bytes += skb->len;
1366 napi_consume_skb(skb, in_napi);
1367 } else {
1368 struct xdp_frame *frame = ptr_to_xdp(ptr);
1369
1370 bytes += frame->len;
1371 xdp_return_frame(frame);
1372 }
1373 packets++;
1374 }
1375
1376 /* Avoid overhead when no packets have been processed
1377 * happens when called speculatively from start_xmit.
1378 */
1379 if (!packets)
1380 return;
1381
1382 u64_stats_update_begin(&sq->stats.syncp);
1383 sq->stats.bytes += bytes;
1384 sq->stats.packets += packets;
1385 u64_stats_update_end(&sq->stats.syncp);
1386}
1387
1388static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
1389{
1390 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
1391 return false;
1392 else if (q < vi->curr_queue_pairs)
1393 return true;
1394 else
1395 return false;
1396}
1397
1398static void virtnet_poll_cleantx(struct receive_queue *rq)
1399{
1400 struct virtnet_info *vi = rq->vq->vdev->priv;
1401 unsigned int index = vq2rxq(rq->vq);
1402 struct send_queue *sq = &vi->sq[index];
1403 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1404
1405 if (!sq->napi.weight || is_xdp_raw_buffer_queue(vi, index))
1406 return;
1407
1408 if (__netif_tx_trylock(txq)) {
1409 free_old_xmit_skbs(sq, true);
1410 __netif_tx_unlock(txq);
1411 }
1412
1413 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1414 netif_tx_wake_queue(txq);
1415}
1416
1417static int virtnet_poll(struct napi_struct *napi, int budget)
1418{
1419 struct receive_queue *rq =
1420 container_of(napi, struct receive_queue, napi);
1421 struct virtnet_info *vi = rq->vq->vdev->priv;
1422 struct send_queue *sq;
1423 unsigned int received;
1424 unsigned int xdp_xmit = 0;
1425
1426 virtnet_poll_cleantx(rq);
1427
1428 received = virtnet_receive(rq, budget, &xdp_xmit);
1429
1430 /* Out of packets? */
1431 if (received < budget)
1432 virtqueue_napi_complete(napi, rq->vq, received);
1433
1434 if (xdp_xmit & VIRTIO_XDP_REDIR)
1435 xdp_do_flush_map();
1436
1437 if (xdp_xmit & VIRTIO_XDP_TX) {
1438 sq = virtnet_xdp_sq(vi);
1439 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1440 u64_stats_update_begin(&sq->stats.syncp);
1441 sq->stats.kicks++;
1442 u64_stats_update_end(&sq->stats.syncp);
1443 }
1444 }
1445
1446 return received;
1447}
1448
1449static int virtnet_open(struct net_device *dev)
1450{
1451 struct virtnet_info *vi = netdev_priv(dev);
1452 int i, err;
1453
1454 for (i = 0; i < vi->max_queue_pairs; i++) {
1455 if (i < vi->curr_queue_pairs)
1456 /* Make sure we have some buffers: if oom use wq. */
1457 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1458 schedule_delayed_work(&vi->refill, 0);
1459
1460 err = xdp_rxq_info_reg(&vi->rq[i].xdp_rxq, dev, i);
1461 if (err < 0)
1462 return err;
1463
1464 err = xdp_rxq_info_reg_mem_model(&vi->rq[i].xdp_rxq,
1465 MEM_TYPE_PAGE_SHARED, NULL);
1466 if (err < 0) {
1467 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
1468 return err;
1469 }
1470
1471 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1472 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
1473 }
1474
1475 return 0;
1476}
1477
1478static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1479{
1480 struct send_queue *sq = container_of(napi, struct send_queue, napi);
1481 struct virtnet_info *vi = sq->vq->vdev->priv;
1482 unsigned int index = vq2txq(sq->vq);
1483 struct netdev_queue *txq;
1484
1485 if (unlikely(is_xdp_raw_buffer_queue(vi, index))) {
1486 /* We don't need to enable cb for XDP */
1487 napi_complete_done(napi, 0);
1488 return 0;
1489 }
1490
1491 txq = netdev_get_tx_queue(vi->dev, index);
1492 __netif_tx_lock(txq, raw_smp_processor_id());
1493 free_old_xmit_skbs(sq, true);
1494 __netif_tx_unlock(txq);
1495
1496 virtqueue_napi_complete(napi, sq->vq, 0);
1497
1498 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1499 netif_tx_wake_queue(txq);
1500
1501 return 0;
1502}
1503
1504static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1505{
1506 struct virtio_net_hdr_mrg_rxbuf *hdr;
1507 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1508 struct virtnet_info *vi = sq->vq->vdev->priv;
1509 int num_sg;
1510 unsigned hdr_len = vi->hdr_len;
1511 bool can_push;
1512
1513 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1514
1515 can_push = vi->any_header_sg &&
1516 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1517 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1518 /* Even if we can, don't push here yet as this would skew
1519 * csum_start offset below. */
1520 if (can_push)
1521 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1522 else
1523 hdr = skb_vnet_hdr(skb);
1524
1525 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1526 virtio_is_little_endian(vi->vdev), false,
1527 0))
1528 BUG();
1529
1530 if (vi->mergeable_rx_bufs)
1531 hdr->num_buffers = 0;
1532
1533 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1534 if (can_push) {
1535 __skb_push(skb, hdr_len);
1536 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1537 if (unlikely(num_sg < 0))
1538 return num_sg;
1539 /* Pull header back to avoid skew in tx bytes calculations. */
1540 __skb_pull(skb, hdr_len);
1541 } else {
1542 sg_set_buf(sq->sg, hdr, hdr_len);
1543 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
1544 if (unlikely(num_sg < 0))
1545 return num_sg;
1546 num_sg++;
1547 }
1548 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1549}
1550
1551static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1552{
1553 struct virtnet_info *vi = netdev_priv(dev);
1554 int qnum = skb_get_queue_mapping(skb);
1555 struct send_queue *sq = &vi->sq[qnum];
1556 int err;
1557 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1558 bool kick = !netdev_xmit_more();
1559 bool use_napi = sq->napi.weight;
1560
1561 /* Free up any pending old buffers before queueing new ones. */
1562 free_old_xmit_skbs(sq, false);
1563
1564 if (use_napi && kick)
1565 virtqueue_enable_cb_delayed(sq->vq);
1566
1567 /* timestamp packet in software */
1568 skb_tx_timestamp(skb);
1569
1570 /* Try to transmit */
1571 err = xmit_skb(sq, skb);
1572
1573 /* This should not happen! */
1574 if (unlikely(err)) {
1575 dev->stats.tx_fifo_errors++;
1576 if (net_ratelimit())
1577 dev_warn(&dev->dev,
1578 "Unexpected TXQ (%d) queue failure: %d\n",
1579 qnum, err);
1580 dev->stats.tx_dropped++;
1581 dev_kfree_skb_any(skb);
1582 return NETDEV_TX_OK;
1583 }
1584
1585 /* Don't wait up for transmitted skbs to be freed. */
1586 if (!use_napi) {
1587 skb_orphan(skb);
1588 nf_reset_ct(skb);
1589 }
1590
1591 /* If running out of space, stop queue to avoid getting packets that we
1592 * are then unable to transmit.
1593 * An alternative would be to force queuing layer to requeue the skb by
1594 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1595 * returned in a normal path of operation: it means that driver is not
1596 * maintaining the TX queue stop/start state properly, and causes
1597 * the stack to do a non-trivial amount of useless work.
1598 * Since most packets only take 1 or 2 ring slots, stopping the queue
1599 * early means 16 slots are typically wasted.
1600 */
1601 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1602 netif_stop_subqueue(dev, qnum);
1603 if (!use_napi &&
1604 unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1605 /* More just got used, free them then recheck. */
1606 free_old_xmit_skbs(sq, false);
1607 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1608 netif_start_subqueue(dev, qnum);
1609 virtqueue_disable_cb(sq->vq);
1610 }
1611 }
1612 }
1613
1614 if (kick || netif_xmit_stopped(txq)) {
1615 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1616 u64_stats_update_begin(&sq->stats.syncp);
1617 sq->stats.kicks++;
1618 u64_stats_update_end(&sq->stats.syncp);
1619 }
1620 }
1621
1622 return NETDEV_TX_OK;
1623}
1624
1625/*
1626 * Send command via the control virtqueue and check status. Commands
1627 * supported by the hypervisor, as indicated by feature bits, should
1628 * never fail unless improperly formatted.
1629 */
1630static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1631 struct scatterlist *out)
1632{
1633 struct scatterlist *sgs[4], hdr, stat;
1634 unsigned out_num = 0, tmp;
1635
1636 /* Caller should know better */
1637 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1638
1639 vi->ctrl->status = ~0;
1640 vi->ctrl->hdr.class = class;
1641 vi->ctrl->hdr.cmd = cmd;
1642 /* Add header */
1643 sg_init_one(&hdr, &vi->ctrl->hdr, sizeof(vi->ctrl->hdr));
1644 sgs[out_num++] = &hdr;
1645
1646 if (out)
1647 sgs[out_num++] = out;
1648
1649 /* Add return status. */
1650 sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status));
1651 sgs[out_num] = &stat;
1652
1653 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1654 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1655
1656 if (unlikely(!virtqueue_kick(vi->cvq)))
1657 return vi->ctrl->status == VIRTIO_NET_OK;
1658
1659 /* Spin for a response, the kick causes an ioport write, trapping
1660 * into the hypervisor, so the request should be handled immediately.
1661 */
1662 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1663 !virtqueue_is_broken(vi->cvq))
1664 cpu_relax();
1665
1666 return vi->ctrl->status == VIRTIO_NET_OK;
1667}
1668
1669static int virtnet_set_mac_address(struct net_device *dev, void *p)
1670{
1671 struct virtnet_info *vi = netdev_priv(dev);
1672 struct virtio_device *vdev = vi->vdev;
1673 int ret;
1674 struct sockaddr *addr;
1675 struct scatterlist sg;
1676
1677 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
1678 return -EOPNOTSUPP;
1679
1680 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
1681 if (!addr)
1682 return -ENOMEM;
1683
1684 ret = eth_prepare_mac_addr_change(dev, addr);
1685 if (ret)
1686 goto out;
1687
1688 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1689 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1690 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1691 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1692 dev_warn(&vdev->dev,
1693 "Failed to set mac address by vq command.\n");
1694 ret = -EINVAL;
1695 goto out;
1696 }
1697 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1698 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1699 unsigned int i;
1700
1701 /* Naturally, this has an atomicity problem. */
1702 for (i = 0; i < dev->addr_len; i++)
1703 virtio_cwrite8(vdev,
1704 offsetof(struct virtio_net_config, mac) +
1705 i, addr->sa_data[i]);
1706 }
1707
1708 eth_commit_mac_addr_change(dev, p);
1709 ret = 0;
1710
1711out:
1712 kfree(addr);
1713 return ret;
1714}
1715
1716static void virtnet_stats(struct net_device *dev,
1717 struct rtnl_link_stats64 *tot)
1718{
1719 struct virtnet_info *vi = netdev_priv(dev);
1720 unsigned int start;
1721 int i;
1722
1723 for (i = 0; i < vi->max_queue_pairs; i++) {
1724 u64 tpackets, tbytes, rpackets, rbytes, rdrops;
1725 struct receive_queue *rq = &vi->rq[i];
1726 struct send_queue *sq = &vi->sq[i];
1727
1728 do {
1729 start = u64_stats_fetch_begin_irq(&sq->stats.syncp);
1730 tpackets = sq->stats.packets;
1731 tbytes = sq->stats.bytes;
1732 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start));
1733
1734 do {
1735 start = u64_stats_fetch_begin_irq(&rq->stats.syncp);
1736 rpackets = rq->stats.packets;
1737 rbytes = rq->stats.bytes;
1738 rdrops = rq->stats.drops;
1739 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start));
1740
1741 tot->rx_packets += rpackets;
1742 tot->tx_packets += tpackets;
1743 tot->rx_bytes += rbytes;
1744 tot->tx_bytes += tbytes;
1745 tot->rx_dropped += rdrops;
1746 }
1747
1748 tot->tx_dropped = dev->stats.tx_dropped;
1749 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1750 tot->rx_length_errors = dev->stats.rx_length_errors;
1751 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1752}
1753
1754static void virtnet_ack_link_announce(struct virtnet_info *vi)
1755{
1756 rtnl_lock();
1757 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1758 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1759 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1760 rtnl_unlock();
1761}
1762
1763static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1764{
1765 struct scatterlist sg;
1766 struct net_device *dev = vi->dev;
1767
1768 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1769 return 0;
1770
1771 vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1772 sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq));
1773
1774 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1775 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1776 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1777 queue_pairs);
1778 return -EINVAL;
1779 } else {
1780 vi->curr_queue_pairs = queue_pairs;
1781 /* virtnet_open() will refill when device is going to up. */
1782 if (dev->flags & IFF_UP)
1783 schedule_delayed_work(&vi->refill, 0);
1784 }
1785
1786 return 0;
1787}
1788
1789static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1790{
1791 int err;
1792
1793 rtnl_lock();
1794 err = _virtnet_set_queues(vi, queue_pairs);
1795 rtnl_unlock();
1796 return err;
1797}
1798
1799static int virtnet_close(struct net_device *dev)
1800{
1801 struct virtnet_info *vi = netdev_priv(dev);
1802 int i;
1803
1804 /* Make sure refill_work doesn't re-enable napi! */
1805 cancel_delayed_work_sync(&vi->refill);
1806
1807 for (i = 0; i < vi->max_queue_pairs; i++) {
1808 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
1809 napi_disable(&vi->rq[i].napi);
1810 virtnet_napi_tx_disable(&vi->sq[i].napi);
1811 }
1812
1813 return 0;
1814}
1815
1816static void virtnet_set_rx_mode(struct net_device *dev)
1817{
1818 struct virtnet_info *vi = netdev_priv(dev);
1819 struct scatterlist sg[2];
1820 struct virtio_net_ctrl_mac *mac_data;
1821 struct netdev_hw_addr *ha;
1822 int uc_count;
1823 int mc_count;
1824 void *buf;
1825 int i;
1826
1827 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1828 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1829 return;
1830
1831 vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0);
1832 vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1833
1834 sg_init_one(sg, &vi->ctrl->promisc, sizeof(vi->ctrl->promisc));
1835
1836 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1837 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1838 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1839 vi->ctrl->promisc ? "en" : "dis");
1840
1841 sg_init_one(sg, &vi->ctrl->allmulti, sizeof(vi->ctrl->allmulti));
1842
1843 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1844 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1845 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1846 vi->ctrl->allmulti ? "en" : "dis");
1847
1848 uc_count = netdev_uc_count(dev);
1849 mc_count = netdev_mc_count(dev);
1850 /* MAC filter - use one buffer for both lists */
1851 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1852 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1853 mac_data = buf;
1854 if (!buf)
1855 return;
1856
1857 sg_init_table(sg, 2);
1858
1859 /* Store the unicast list and count in the front of the buffer */
1860 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1861 i = 0;
1862 netdev_for_each_uc_addr(ha, dev)
1863 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1864
1865 sg_set_buf(&sg[0], mac_data,
1866 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1867
1868 /* multicast list and count fill the end */
1869 mac_data = (void *)&mac_data->macs[uc_count][0];
1870
1871 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1872 i = 0;
1873 netdev_for_each_mc_addr(ha, dev)
1874 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1875
1876 sg_set_buf(&sg[1], mac_data,
1877 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1878
1879 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1880 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1881 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1882
1883 kfree(buf);
1884}
1885
1886static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1887 __be16 proto, u16 vid)
1888{
1889 struct virtnet_info *vi = netdev_priv(dev);
1890 struct scatterlist sg;
1891
1892 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
1893 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
1894
1895 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1896 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1897 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1898 return 0;
1899}
1900
1901static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1902 __be16 proto, u16 vid)
1903{
1904 struct virtnet_info *vi = netdev_priv(dev);
1905 struct scatterlist sg;
1906
1907 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
1908 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
1909
1910 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1911 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1912 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1913 return 0;
1914}
1915
1916static void virtnet_clean_affinity(struct virtnet_info *vi)
1917{
1918 int i;
1919
1920 if (vi->affinity_hint_set) {
1921 for (i = 0; i < vi->max_queue_pairs; i++) {
1922 virtqueue_set_affinity(vi->rq[i].vq, NULL);
1923 virtqueue_set_affinity(vi->sq[i].vq, NULL);
1924 }
1925
1926 vi->affinity_hint_set = false;
1927 }
1928}
1929
1930static void virtnet_set_affinity(struct virtnet_info *vi)
1931{
1932 cpumask_var_t mask;
1933 int stragglers;
1934 int group_size;
1935 int i, j, cpu;
1936 int num_cpu;
1937 int stride;
1938
1939 if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
1940 virtnet_clean_affinity(vi);
1941 return;
1942 }
1943
1944 num_cpu = num_online_cpus();
1945 stride = max_t(int, num_cpu / vi->curr_queue_pairs, 1);
1946 stragglers = num_cpu >= vi->curr_queue_pairs ?
1947 num_cpu % vi->curr_queue_pairs :
1948 0;
1949 cpu = cpumask_next(-1, cpu_online_mask);
1950
1951 for (i = 0; i < vi->curr_queue_pairs; i++) {
1952 group_size = stride + (i < stragglers ? 1 : 0);
1953
1954 for (j = 0; j < group_size; j++) {
1955 cpumask_set_cpu(cpu, mask);
1956 cpu = cpumask_next_wrap(cpu, cpu_online_mask,
1957 nr_cpu_ids, false);
1958 }
1959 virtqueue_set_affinity(vi->rq[i].vq, mask);
1960 virtqueue_set_affinity(vi->sq[i].vq, mask);
1961 __netif_set_xps_queue(vi->dev, cpumask_bits(mask), i, false);
1962 cpumask_clear(mask);
1963 }
1964
1965 vi->affinity_hint_set = true;
1966 free_cpumask_var(mask);
1967}
1968
1969static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1970{
1971 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1972 node);
1973 virtnet_set_affinity(vi);
1974 return 0;
1975}
1976
1977static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1978{
1979 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1980 node_dead);
1981 virtnet_set_affinity(vi);
1982 return 0;
1983}
1984
1985static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1986{
1987 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1988 node);
1989
1990 virtnet_clean_affinity(vi);
1991 return 0;
1992}
1993
1994static enum cpuhp_state virtionet_online;
1995
1996static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1997{
1998 int ret;
1999
2000 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
2001 if (ret)
2002 return ret;
2003 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2004 &vi->node_dead);
2005 if (!ret)
2006 return ret;
2007 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2008 return ret;
2009}
2010
2011static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
2012{
2013 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2014 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2015 &vi->node_dead);
2016}
2017
2018static void virtnet_get_ringparam(struct net_device *dev,
2019 struct ethtool_ringparam *ring)
2020{
2021 struct virtnet_info *vi = netdev_priv(dev);
2022
2023 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
2024 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
2025 ring->rx_pending = ring->rx_max_pending;
2026 ring->tx_pending = ring->tx_max_pending;
2027}
2028
2029
2030static void virtnet_get_drvinfo(struct net_device *dev,
2031 struct ethtool_drvinfo *info)
2032{
2033 struct virtnet_info *vi = netdev_priv(dev);
2034 struct virtio_device *vdev = vi->vdev;
2035
2036 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
2037 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
2038 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
2039
2040}
2041
2042/* TODO: Eliminate OOO packets during switching */
2043static int virtnet_set_channels(struct net_device *dev,
2044 struct ethtool_channels *channels)
2045{
2046 struct virtnet_info *vi = netdev_priv(dev);
2047 u16 queue_pairs = channels->combined_count;
2048 int err;
2049
2050 /* We don't support separate rx/tx channels.
2051 * We don't allow setting 'other' channels.
2052 */
2053 if (channels->rx_count || channels->tx_count || channels->other_count)
2054 return -EINVAL;
2055
2056 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
2057 return -EINVAL;
2058
2059 /* For now we don't support modifying channels while XDP is loaded
2060 * also when XDP is loaded all RX queues have XDP programs so we only
2061 * need to check a single RX queue.
2062 */
2063 if (vi->rq[0].xdp_prog)
2064 return -EINVAL;
2065
2066 get_online_cpus();
2067 err = _virtnet_set_queues(vi, queue_pairs);
2068 if (!err) {
2069 netif_set_real_num_tx_queues(dev, queue_pairs);
2070 netif_set_real_num_rx_queues(dev, queue_pairs);
2071
2072 virtnet_set_affinity(vi);
2073 }
2074 put_online_cpus();
2075
2076 return err;
2077}
2078
2079static void virtnet_get_strings(struct net_device *dev, u32 stringset, u8 *data)
2080{
2081 struct virtnet_info *vi = netdev_priv(dev);
2082 char *p = (char *)data;
2083 unsigned int i, j;
2084
2085 switch (stringset) {
2086 case ETH_SS_STATS:
2087 for (i = 0; i < vi->curr_queue_pairs; i++) {
2088 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2089 snprintf(p, ETH_GSTRING_LEN, "rx_queue_%u_%s",
2090 i, virtnet_rq_stats_desc[j].desc);
2091 p += ETH_GSTRING_LEN;
2092 }
2093 }
2094
2095 for (i = 0; i < vi->curr_queue_pairs; i++) {
2096 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2097 snprintf(p, ETH_GSTRING_LEN, "tx_queue_%u_%s",
2098 i, virtnet_sq_stats_desc[j].desc);
2099 p += ETH_GSTRING_LEN;
2100 }
2101 }
2102 break;
2103 }
2104}
2105
2106static int virtnet_get_sset_count(struct net_device *dev, int sset)
2107{
2108 struct virtnet_info *vi = netdev_priv(dev);
2109
2110 switch (sset) {
2111 case ETH_SS_STATS:
2112 return vi->curr_queue_pairs * (VIRTNET_RQ_STATS_LEN +
2113 VIRTNET_SQ_STATS_LEN);
2114 default:
2115 return -EOPNOTSUPP;
2116 }
2117}
2118
2119static void virtnet_get_ethtool_stats(struct net_device *dev,
2120 struct ethtool_stats *stats, u64 *data)
2121{
2122 struct virtnet_info *vi = netdev_priv(dev);
2123 unsigned int idx = 0, start, i, j;
2124 const u8 *stats_base;
2125 size_t offset;
2126
2127 for (i = 0; i < vi->curr_queue_pairs; i++) {
2128 struct receive_queue *rq = &vi->rq[i];
2129
2130 stats_base = (u8 *)&rq->stats;
2131 do {
2132 start = u64_stats_fetch_begin_irq(&rq->stats.syncp);
2133 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2134 offset = virtnet_rq_stats_desc[j].offset;
2135 data[idx + j] = *(u64 *)(stats_base + offset);
2136 }
2137 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start));
2138 idx += VIRTNET_RQ_STATS_LEN;
2139 }
2140
2141 for (i = 0; i < vi->curr_queue_pairs; i++) {
2142 struct send_queue *sq = &vi->sq[i];
2143
2144 stats_base = (u8 *)&sq->stats;
2145 do {
2146 start = u64_stats_fetch_begin_irq(&sq->stats.syncp);
2147 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2148 offset = virtnet_sq_stats_desc[j].offset;
2149 data[idx + j] = *(u64 *)(stats_base + offset);
2150 }
2151 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start));
2152 idx += VIRTNET_SQ_STATS_LEN;
2153 }
2154}
2155
2156static void virtnet_get_channels(struct net_device *dev,
2157 struct ethtool_channels *channels)
2158{
2159 struct virtnet_info *vi = netdev_priv(dev);
2160
2161 channels->combined_count = vi->curr_queue_pairs;
2162 channels->max_combined = vi->max_queue_pairs;
2163 channels->max_other = 0;
2164 channels->rx_count = 0;
2165 channels->tx_count = 0;
2166 channels->other_count = 0;
2167}
2168
2169/* Check if the user is trying to change anything besides speed/duplex */
2170static bool
2171virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings *cmd)
2172{
2173 struct ethtool_link_ksettings diff1 = *cmd;
2174 struct ethtool_link_ksettings diff2 = {};
2175
2176 /* cmd is always set so we need to clear it, validate the port type
2177 * and also without autonegotiation we can ignore advertising
2178 */
2179 diff1.base.speed = 0;
2180 diff2.base.port = PORT_OTHER;
2181 ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
2182 diff1.base.duplex = 0;
2183 diff1.base.cmd = 0;
2184 diff1.base.link_mode_masks_nwords = 0;
2185
2186 return !memcmp(&diff1.base, &diff2.base, sizeof(diff1.base)) &&
2187 bitmap_empty(diff1.link_modes.supported,
2188 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
2189 bitmap_empty(diff1.link_modes.advertising,
2190 __ETHTOOL_LINK_MODE_MASK_NBITS) &&
2191 bitmap_empty(diff1.link_modes.lp_advertising,
2192 __ETHTOOL_LINK_MODE_MASK_NBITS);
2193}
2194
2195static int virtnet_set_link_ksettings(struct net_device *dev,
2196 const struct ethtool_link_ksettings *cmd)
2197{
2198 struct virtnet_info *vi = netdev_priv(dev);
2199 u32 speed;
2200
2201 speed = cmd->base.speed;
2202 /* don't allow custom speed and duplex */
2203 if (!ethtool_validate_speed(speed) ||
2204 !ethtool_validate_duplex(cmd->base.duplex) ||
2205 !virtnet_validate_ethtool_cmd(cmd))
2206 return -EINVAL;
2207 vi->speed = speed;
2208 vi->duplex = cmd->base.duplex;
2209
2210 return 0;
2211}
2212
2213static int virtnet_get_link_ksettings(struct net_device *dev,
2214 struct ethtool_link_ksettings *cmd)
2215{
2216 struct virtnet_info *vi = netdev_priv(dev);
2217
2218 cmd->base.speed = vi->speed;
2219 cmd->base.duplex = vi->duplex;
2220 cmd->base.port = PORT_OTHER;
2221
2222 return 0;
2223}
2224
2225static int virtnet_set_coalesce(struct net_device *dev,
2226 struct ethtool_coalesce *ec)
2227{
2228 struct ethtool_coalesce ec_default = {
2229 .cmd = ETHTOOL_SCOALESCE,
2230 .rx_max_coalesced_frames = 1,
2231 };
2232 struct virtnet_info *vi = netdev_priv(dev);
2233 int i, napi_weight;
2234
2235 if (ec->tx_max_coalesced_frames > 1)
2236 return -EINVAL;
2237
2238 ec_default.tx_max_coalesced_frames = ec->tx_max_coalesced_frames;
2239 napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
2240
2241 /* disallow changes to fields not explicitly tested above */
2242 if (memcmp(ec, &ec_default, sizeof(ec_default)))
2243 return -EINVAL;
2244
2245 if (napi_weight ^ vi->sq[0].napi.weight) {
2246 if (dev->flags & IFF_UP)
2247 return -EBUSY;
2248 for (i = 0; i < vi->max_queue_pairs; i++)
2249 vi->sq[i].napi.weight = napi_weight;
2250 }
2251
2252 return 0;
2253}
2254
2255static int virtnet_get_coalesce(struct net_device *dev,
2256 struct ethtool_coalesce *ec)
2257{
2258 struct ethtool_coalesce ec_default = {
2259 .cmd = ETHTOOL_GCOALESCE,
2260 .rx_max_coalesced_frames = 1,
2261 };
2262 struct virtnet_info *vi = netdev_priv(dev);
2263
2264 memcpy(ec, &ec_default, sizeof(ec_default));
2265
2266 if (vi->sq[0].napi.weight)
2267 ec->tx_max_coalesced_frames = 1;
2268
2269 return 0;
2270}
2271
2272static void virtnet_init_settings(struct net_device *dev)
2273{
2274 struct virtnet_info *vi = netdev_priv(dev);
2275
2276 vi->speed = SPEED_UNKNOWN;
2277 vi->duplex = DUPLEX_UNKNOWN;
2278}
2279
2280static void virtnet_update_settings(struct virtnet_info *vi)
2281{
2282 u32 speed;
2283 u8 duplex;
2284
2285 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
2286 return;
2287
2288 speed = virtio_cread32(vi->vdev, offsetof(struct virtio_net_config,
2289 speed));
2290 if (ethtool_validate_speed(speed))
2291 vi->speed = speed;
2292 duplex = virtio_cread8(vi->vdev, offsetof(struct virtio_net_config,
2293 duplex));
2294 if (ethtool_validate_duplex(duplex))
2295 vi->duplex = duplex;
2296}
2297
2298static const struct ethtool_ops virtnet_ethtool_ops = {
2299 .get_drvinfo = virtnet_get_drvinfo,
2300 .get_link = ethtool_op_get_link,
2301 .get_ringparam = virtnet_get_ringparam,
2302 .get_strings = virtnet_get_strings,
2303 .get_sset_count = virtnet_get_sset_count,
2304 .get_ethtool_stats = virtnet_get_ethtool_stats,
2305 .set_channels = virtnet_set_channels,
2306 .get_channels = virtnet_get_channels,
2307 .get_ts_info = ethtool_op_get_ts_info,
2308 .get_link_ksettings = virtnet_get_link_ksettings,
2309 .set_link_ksettings = virtnet_set_link_ksettings,
2310 .set_coalesce = virtnet_set_coalesce,
2311 .get_coalesce = virtnet_get_coalesce,
2312};
2313
2314static void virtnet_freeze_down(struct virtio_device *vdev)
2315{
2316 struct virtnet_info *vi = vdev->priv;
2317 int i;
2318
2319 /* Make sure no work handler is accessing the device */
2320 flush_work(&vi->config_work);
2321
2322 netif_tx_lock_bh(vi->dev);
2323 netif_device_detach(vi->dev);
2324 netif_tx_unlock_bh(vi->dev);
2325 cancel_delayed_work_sync(&vi->refill);
2326
2327 if (netif_running(vi->dev)) {
2328 for (i = 0; i < vi->max_queue_pairs; i++) {
2329 napi_disable(&vi->rq[i].napi);
2330 virtnet_napi_tx_disable(&vi->sq[i].napi);
2331 }
2332 }
2333}
2334
2335static int init_vqs(struct virtnet_info *vi);
2336
2337static int virtnet_restore_up(struct virtio_device *vdev)
2338{
2339 struct virtnet_info *vi = vdev->priv;
2340 int err, i;
2341
2342 err = init_vqs(vi);
2343 if (err)
2344 return err;
2345
2346 virtio_device_ready(vdev);
2347
2348 if (netif_running(vi->dev)) {
2349 for (i = 0; i < vi->curr_queue_pairs; i++)
2350 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
2351 schedule_delayed_work(&vi->refill, 0);
2352
2353 for (i = 0; i < vi->max_queue_pairs; i++) {
2354 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2355 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
2356 &vi->sq[i].napi);
2357 }
2358 }
2359
2360 netif_tx_lock_bh(vi->dev);
2361 netif_device_attach(vi->dev);
2362 netif_tx_unlock_bh(vi->dev);
2363 return err;
2364}
2365
2366static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
2367{
2368 struct scatterlist sg;
2369 vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads);
2370
2371 sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads));
2372
2373 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
2374 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
2375 dev_warn(&vi->dev->dev, "Fail to set guest offload.\n");
2376 return -EINVAL;
2377 }
2378
2379 return 0;
2380}
2381
2382static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
2383{
2384 u64 offloads = 0;
2385
2386 if (!vi->guest_offloads)
2387 return 0;
2388
2389 return virtnet_set_guest_offloads(vi, offloads);
2390}
2391
2392static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
2393{
2394 u64 offloads = vi->guest_offloads;
2395
2396 if (!vi->guest_offloads)
2397 return 0;
2398
2399 return virtnet_set_guest_offloads(vi, offloads);
2400}
2401
2402static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
2403 struct netlink_ext_ack *extack)
2404{
2405 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
2406 struct virtnet_info *vi = netdev_priv(dev);
2407 struct bpf_prog *old_prog;
2408 u16 xdp_qp = 0, curr_qp;
2409 int i, err;
2410
2411 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
2412 && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2413 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2414 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
2415 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
2416 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))) {
2417 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO/CSUM, disable LRO/CSUM first");
2418 return -EOPNOTSUPP;
2419 }
2420
2421 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
2422 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
2423 return -EINVAL;
2424 }
2425
2426 if (dev->mtu > max_sz) {
2427 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
2428 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
2429 return -EINVAL;
2430 }
2431
2432 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
2433 if (prog)
2434 xdp_qp = nr_cpu_ids;
2435
2436 /* XDP requires extra queues for XDP_TX */
2437 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
2438 NL_SET_ERR_MSG_MOD(extack, "Too few free TX rings available");
2439 netdev_warn(dev, "request %i queues but max is %i\n",
2440 curr_qp + xdp_qp, vi->max_queue_pairs);
2441 return -ENOMEM;
2442 }
2443
2444 old_prog = rtnl_dereference(vi->rq[0].xdp_prog);
2445 if (!prog && !old_prog)
2446 return 0;
2447
2448 if (prog) {
2449 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
2450 if (IS_ERR(prog))
2451 return PTR_ERR(prog);
2452 }
2453
2454 /* Make sure NAPI is not using any XDP TX queues for RX. */
2455 if (netif_running(dev)) {
2456 for (i = 0; i < vi->max_queue_pairs; i++) {
2457 napi_disable(&vi->rq[i].napi);
2458 virtnet_napi_tx_disable(&vi->sq[i].napi);
2459 }
2460 }
2461
2462 if (!prog) {
2463 for (i = 0; i < vi->max_queue_pairs; i++) {
2464 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
2465 if (i == 0)
2466 virtnet_restore_guest_offloads(vi);
2467 }
2468 synchronize_net();
2469 }
2470
2471 err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
2472 if (err)
2473 goto err;
2474 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
2475 vi->xdp_queue_pairs = xdp_qp;
2476
2477 if (prog) {
2478 for (i = 0; i < vi->max_queue_pairs; i++) {
2479 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
2480 if (i == 0 && !old_prog)
2481 virtnet_clear_guest_offloads(vi);
2482 }
2483 }
2484
2485 for (i = 0; i < vi->max_queue_pairs; i++) {
2486 if (old_prog)
2487 bpf_prog_put(old_prog);
2488 if (netif_running(dev)) {
2489 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2490 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
2491 &vi->sq[i].napi);
2492 }
2493 }
2494
2495 return 0;
2496
2497err:
2498 if (!prog) {
2499 virtnet_clear_guest_offloads(vi);
2500 for (i = 0; i < vi->max_queue_pairs; i++)
2501 rcu_assign_pointer(vi->rq[i].xdp_prog, old_prog);
2502 }
2503
2504 if (netif_running(dev)) {
2505 for (i = 0; i < vi->max_queue_pairs; i++) {
2506 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2507 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
2508 &vi->sq[i].napi);
2509 }
2510 }
2511 if (prog)
2512 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
2513 return err;
2514}
2515
2516static u32 virtnet_xdp_query(struct net_device *dev)
2517{
2518 struct virtnet_info *vi = netdev_priv(dev);
2519 const struct bpf_prog *xdp_prog;
2520 int i;
2521
2522 for (i = 0; i < vi->max_queue_pairs; i++) {
2523 xdp_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2524 if (xdp_prog)
2525 return xdp_prog->aux->id;
2526 }
2527 return 0;
2528}
2529
2530static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
2531{
2532 switch (xdp->command) {
2533 case XDP_SETUP_PROG:
2534 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
2535 case XDP_QUERY_PROG:
2536 xdp->prog_id = virtnet_xdp_query(dev);
2537 return 0;
2538 default:
2539 return -EINVAL;
2540 }
2541}
2542
2543static int virtnet_get_phys_port_name(struct net_device *dev, char *buf,
2544 size_t len)
2545{
2546 struct virtnet_info *vi = netdev_priv(dev);
2547 int ret;
2548
2549 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
2550 return -EOPNOTSUPP;
2551
2552 ret = snprintf(buf, len, "sby");
2553 if (ret >= len)
2554 return -EOPNOTSUPP;
2555
2556 return 0;
2557}
2558
2559static int virtnet_set_features(struct net_device *dev,
2560 netdev_features_t features)
2561{
2562 struct virtnet_info *vi = netdev_priv(dev);
2563 u64 offloads;
2564 int err;
2565
2566 if ((dev->features ^ features) & NETIF_F_LRO) {
2567 if (vi->xdp_queue_pairs)
2568 return -EBUSY;
2569
2570 if (features & NETIF_F_LRO)
2571 offloads = vi->guest_offloads_capable;
2572 else
2573 offloads = 0;
2574
2575 err = virtnet_set_guest_offloads(vi, offloads);
2576 if (err)
2577 return err;
2578 vi->guest_offloads = offloads;
2579 }
2580
2581 return 0;
2582}
2583
2584static const struct net_device_ops virtnet_netdev = {
2585 .ndo_open = virtnet_open,
2586 .ndo_stop = virtnet_close,
2587 .ndo_start_xmit = start_xmit,
2588 .ndo_validate_addr = eth_validate_addr,
2589 .ndo_set_mac_address = virtnet_set_mac_address,
2590 .ndo_set_rx_mode = virtnet_set_rx_mode,
2591 .ndo_get_stats64 = virtnet_stats,
2592 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
2593 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
2594 .ndo_bpf = virtnet_xdp,
2595 .ndo_xdp_xmit = virtnet_xdp_xmit,
2596 .ndo_features_check = passthru_features_check,
2597 .ndo_get_phys_port_name = virtnet_get_phys_port_name,
2598 .ndo_set_features = virtnet_set_features,
2599};
2600
2601static void virtnet_config_changed_work(struct work_struct *work)
2602{
2603 struct virtnet_info *vi =
2604 container_of(work, struct virtnet_info, config_work);
2605 u16 v;
2606
2607 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
2608 struct virtio_net_config, status, &v) < 0)
2609 return;
2610
2611 if (v & VIRTIO_NET_S_ANNOUNCE) {
2612 netdev_notify_peers(vi->dev);
2613 virtnet_ack_link_announce(vi);
2614 }
2615
2616 /* Ignore unknown (future) status bits */
2617 v &= VIRTIO_NET_S_LINK_UP;
2618
2619 if (vi->status == v)
2620 return;
2621
2622 vi->status = v;
2623
2624 if (vi->status & VIRTIO_NET_S_LINK_UP) {
2625 virtnet_update_settings(vi);
2626 netif_carrier_on(vi->dev);
2627 netif_tx_wake_all_queues(vi->dev);
2628 } else {
2629 netif_carrier_off(vi->dev);
2630 netif_tx_stop_all_queues(vi->dev);
2631 }
2632}
2633
2634static void virtnet_config_changed(struct virtio_device *vdev)
2635{
2636 struct virtnet_info *vi = vdev->priv;
2637
2638 schedule_work(&vi->config_work);
2639}
2640
2641static void virtnet_free_queues(struct virtnet_info *vi)
2642{
2643 int i;
2644
2645 for (i = 0; i < vi->max_queue_pairs; i++) {
2646 napi_hash_del(&vi->rq[i].napi);
2647 netif_napi_del(&vi->rq[i].napi);
2648 netif_napi_del(&vi->sq[i].napi);
2649 }
2650
2651 /* We called napi_hash_del() before netif_napi_del(),
2652 * we need to respect an RCU grace period before freeing vi->rq
2653 */
2654 synchronize_net();
2655
2656 kfree(vi->rq);
2657 kfree(vi->sq);
2658 kfree(vi->ctrl);
2659}
2660
2661static void _free_receive_bufs(struct virtnet_info *vi)
2662{
2663 struct bpf_prog *old_prog;
2664 int i;
2665
2666 for (i = 0; i < vi->max_queue_pairs; i++) {
2667 while (vi->rq[i].pages)
2668 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
2669
2670 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2671 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
2672 if (old_prog)
2673 bpf_prog_put(old_prog);
2674 }
2675}
2676
2677static void free_receive_bufs(struct virtnet_info *vi)
2678{
2679 rtnl_lock();
2680 _free_receive_bufs(vi);
2681 rtnl_unlock();
2682}
2683
2684static void free_receive_page_frags(struct virtnet_info *vi)
2685{
2686 int i;
2687 for (i = 0; i < vi->max_queue_pairs; i++)
2688 if (vi->rq[i].alloc_frag.page)
2689 put_page(vi->rq[i].alloc_frag.page);
2690}
2691
2692static void free_unused_bufs(struct virtnet_info *vi)
2693{
2694 void *buf;
2695 int i;
2696
2697 for (i = 0; i < vi->max_queue_pairs; i++) {
2698 struct virtqueue *vq = vi->sq[i].vq;
2699 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2700 if (!is_xdp_frame(buf))
2701 dev_kfree_skb(buf);
2702 else
2703 xdp_return_frame(ptr_to_xdp(buf));
2704 }
2705 }
2706
2707 for (i = 0; i < vi->max_queue_pairs; i++) {
2708 struct virtqueue *vq = vi->rq[i].vq;
2709
2710 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2711 if (vi->mergeable_rx_bufs) {
2712 put_page(virt_to_head_page(buf));
2713 } else if (vi->big_packets) {
2714 give_pages(&vi->rq[i], buf);
2715 } else {
2716 put_page(virt_to_head_page(buf));
2717 }
2718 }
2719 }
2720}
2721
2722static void virtnet_del_vqs(struct virtnet_info *vi)
2723{
2724 struct virtio_device *vdev = vi->vdev;
2725
2726 virtnet_clean_affinity(vi);
2727
2728 vdev->config->del_vqs(vdev);
2729
2730 virtnet_free_queues(vi);
2731}
2732
2733/* How large should a single buffer be so a queue full of these can fit at
2734 * least one full packet?
2735 * Logic below assumes the mergeable buffer header is used.
2736 */
2737static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
2738{
2739 const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2740 unsigned int rq_size = virtqueue_get_vring_size(vq);
2741 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
2742 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
2743 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
2744
2745 return max(max(min_buf_len, hdr_len) - hdr_len,
2746 (unsigned int)GOOD_PACKET_LEN);
2747}
2748
2749static int virtnet_find_vqs(struct virtnet_info *vi)
2750{
2751 vq_callback_t **callbacks;
2752 struct virtqueue **vqs;
2753 int ret = -ENOMEM;
2754 int i, total_vqs;
2755 const char **names;
2756 bool *ctx;
2757
2758 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2759 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2760 * possible control vq.
2761 */
2762 total_vqs = vi->max_queue_pairs * 2 +
2763 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
2764
2765 /* Allocate space for find_vqs parameters */
2766 vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
2767 if (!vqs)
2768 goto err_vq;
2769 callbacks = kmalloc_array(total_vqs, sizeof(*callbacks), GFP_KERNEL);
2770 if (!callbacks)
2771 goto err_callback;
2772 names = kmalloc_array(total_vqs, sizeof(*names), GFP_KERNEL);
2773 if (!names)
2774 goto err_names;
2775 if (!vi->big_packets || vi->mergeable_rx_bufs) {
2776 ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL);
2777 if (!ctx)
2778 goto err_ctx;
2779 } else {
2780 ctx = NULL;
2781 }
2782
2783 /* Parameters for control virtqueue, if any */
2784 if (vi->has_cvq) {
2785 callbacks[total_vqs - 1] = NULL;
2786 names[total_vqs - 1] = "control";
2787 }
2788
2789 /* Allocate/initialize parameters for send/receive virtqueues */
2790 for (i = 0; i < vi->max_queue_pairs; i++) {
2791 callbacks[rxq2vq(i)] = skb_recv_done;
2792 callbacks[txq2vq(i)] = skb_xmit_done;
2793 sprintf(vi->rq[i].name, "input.%d", i);
2794 sprintf(vi->sq[i].name, "output.%d", i);
2795 names[rxq2vq(i)] = vi->rq[i].name;
2796 names[txq2vq(i)] = vi->sq[i].name;
2797 if (ctx)
2798 ctx[rxq2vq(i)] = true;
2799 }
2800
2801 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2802 names, ctx, NULL);
2803 if (ret)
2804 goto err_find;
2805
2806 if (vi->has_cvq) {
2807 vi->cvq = vqs[total_vqs - 1];
2808 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2809 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2810 }
2811
2812 for (i = 0; i < vi->max_queue_pairs; i++) {
2813 vi->rq[i].vq = vqs[rxq2vq(i)];
2814 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
2815 vi->sq[i].vq = vqs[txq2vq(i)];
2816 }
2817
2818 /* run here: ret == 0. */
2819
2820
2821err_find:
2822 kfree(ctx);
2823err_ctx:
2824 kfree(names);
2825err_names:
2826 kfree(callbacks);
2827err_callback:
2828 kfree(vqs);
2829err_vq:
2830 return ret;
2831}
2832
2833static int virtnet_alloc_queues(struct virtnet_info *vi)
2834{
2835 int i;
2836
2837 vi->ctrl = kzalloc(sizeof(*vi->ctrl), GFP_KERNEL);
2838 if (!vi->ctrl)
2839 goto err_ctrl;
2840 vi->sq = kcalloc(vi->max_queue_pairs, sizeof(*vi->sq), GFP_KERNEL);
2841 if (!vi->sq)
2842 goto err_sq;
2843 vi->rq = kcalloc(vi->max_queue_pairs, sizeof(*vi->rq), GFP_KERNEL);
2844 if (!vi->rq)
2845 goto err_rq;
2846
2847 INIT_DELAYED_WORK(&vi->refill, refill_work);
2848 for (i = 0; i < vi->max_queue_pairs; i++) {
2849 vi->rq[i].pages = NULL;
2850 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2851 napi_weight);
2852 netif_tx_napi_add(vi->dev, &vi->sq[i].napi, virtnet_poll_tx,
2853 napi_tx ? napi_weight : 0);
2854
2855 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2856 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2857 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2858
2859 u64_stats_init(&vi->rq[i].stats.syncp);
2860 u64_stats_init(&vi->sq[i].stats.syncp);
2861 }
2862
2863 return 0;
2864
2865err_rq:
2866 kfree(vi->sq);
2867err_sq:
2868 kfree(vi->ctrl);
2869err_ctrl:
2870 return -ENOMEM;
2871}
2872
2873static int init_vqs(struct virtnet_info *vi)
2874{
2875 int ret;
2876
2877 /* Allocate send & receive queues */
2878 ret = virtnet_alloc_queues(vi);
2879 if (ret)
2880 goto err;
2881
2882 ret = virtnet_find_vqs(vi);
2883 if (ret)
2884 goto err_free;
2885
2886 get_online_cpus();
2887 virtnet_set_affinity(vi);
2888 put_online_cpus();
2889
2890 return 0;
2891
2892err_free:
2893 virtnet_free_queues(vi);
2894err:
2895 return ret;
2896}
2897
2898#ifdef CONFIG_SYSFS
2899static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2900 char *buf)
2901{
2902 struct virtnet_info *vi = netdev_priv(queue->dev);
2903 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2904 unsigned int headroom = virtnet_get_headroom(vi);
2905 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
2906 struct ewma_pkt_len *avg;
2907
2908 BUG_ON(queue_index >= vi->max_queue_pairs);
2909 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2910 return sprintf(buf, "%u\n",
2911 get_mergeable_buf_len(&vi->rq[queue_index], avg,
2912 SKB_DATA_ALIGN(headroom + tailroom)));
2913}
2914
2915static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2916 __ATTR_RO(mergeable_rx_buffer_size);
2917
2918static struct attribute *virtio_net_mrg_rx_attrs[] = {
2919 &mergeable_rx_buffer_size_attribute.attr,
2920 NULL
2921};
2922
2923static const struct attribute_group virtio_net_mrg_rx_group = {
2924 .name = "virtio_net",
2925 .attrs = virtio_net_mrg_rx_attrs
2926};
2927#endif
2928
2929static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2930 unsigned int fbit,
2931 const char *fname, const char *dname)
2932{
2933 if (!virtio_has_feature(vdev, fbit))
2934 return false;
2935
2936 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2937 fname, dname);
2938
2939 return true;
2940}
2941
2942#define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2943 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2944
2945static bool virtnet_validate_features(struct virtio_device *vdev)
2946{
2947 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2948 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2949 "VIRTIO_NET_F_CTRL_VQ") ||
2950 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2951 "VIRTIO_NET_F_CTRL_VQ") ||
2952 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2953 "VIRTIO_NET_F_CTRL_VQ") ||
2954 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2955 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2956 "VIRTIO_NET_F_CTRL_VQ"))) {
2957 return false;
2958 }
2959
2960 return true;
2961}
2962
2963#define MIN_MTU ETH_MIN_MTU
2964#define MAX_MTU ETH_MAX_MTU
2965
2966static int virtnet_validate(struct virtio_device *vdev)
2967{
2968 if (!vdev->config->get) {
2969 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2970 __func__);
2971 return -EINVAL;
2972 }
2973
2974 if (!virtnet_validate_features(vdev))
2975 return -EINVAL;
2976
2977 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2978 int mtu = virtio_cread16(vdev,
2979 offsetof(struct virtio_net_config,
2980 mtu));
2981 if (mtu < MIN_MTU)
2982 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2983 }
2984
2985 return 0;
2986}
2987
2988static int virtnet_probe(struct virtio_device *vdev)
2989{
2990 int i, err = -ENOMEM;
2991 struct net_device *dev;
2992 struct virtnet_info *vi;
2993 u16 max_queue_pairs;
2994 int mtu;
2995
2996 /* Find if host supports multiqueue virtio_net device */
2997 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2998 struct virtio_net_config,
2999 max_virtqueue_pairs, &max_queue_pairs);
3000
3001 /* We need at least 2 queue's */
3002 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
3003 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
3004 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
3005 max_queue_pairs = 1;
3006
3007 /* Allocate ourselves a network device with room for our info */
3008 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
3009 if (!dev)
3010 return -ENOMEM;
3011
3012 /* Set up network device as normal. */
3013 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
3014 dev->netdev_ops = &virtnet_netdev;
3015 dev->features = NETIF_F_HIGHDMA;
3016
3017 dev->ethtool_ops = &virtnet_ethtool_ops;
3018 SET_NETDEV_DEV(dev, &vdev->dev);
3019
3020 /* Do we support "hardware" checksums? */
3021 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
3022 /* This opens up the world of extra features. */
3023 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
3024 if (csum)
3025 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
3026
3027 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
3028 dev->hw_features |= NETIF_F_TSO
3029 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
3030 }
3031 /* Individual feature bits: what can host handle? */
3032 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
3033 dev->hw_features |= NETIF_F_TSO;
3034 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
3035 dev->hw_features |= NETIF_F_TSO6;
3036 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
3037 dev->hw_features |= NETIF_F_TSO_ECN;
3038
3039 dev->features |= NETIF_F_GSO_ROBUST;
3040
3041 if (gso)
3042 dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
3043 /* (!csum && gso) case will be fixed by register_netdev() */
3044 }
3045 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
3046 dev->features |= NETIF_F_RXCSUM;
3047 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3048 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6))
3049 dev->features |= NETIF_F_LRO;
3050 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS))
3051 dev->hw_features |= NETIF_F_LRO;
3052
3053 dev->vlan_features = dev->features;
3054
3055 /* MTU range: 68 - 65535 */
3056 dev->min_mtu = MIN_MTU;
3057 dev->max_mtu = MAX_MTU;
3058
3059 /* Configuration may specify what MAC to use. Otherwise random. */
3060 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
3061 virtio_cread_bytes(vdev,
3062 offsetof(struct virtio_net_config, mac),
3063 dev->dev_addr, dev->addr_len);
3064 else
3065 eth_hw_addr_random(dev);
3066
3067 /* Set up our device-specific information */
3068 vi = netdev_priv(dev);
3069 vi->dev = dev;
3070 vi->vdev = vdev;
3071 vdev->priv = vi;
3072
3073 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
3074
3075 /* If we can receive ANY GSO packets, we must allocate large ones. */
3076 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3077 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
3078 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
3079 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
3080 vi->big_packets = true;
3081
3082 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
3083 vi->mergeable_rx_bufs = true;
3084
3085 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
3086 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
3087 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
3088 else
3089 vi->hdr_len = sizeof(struct virtio_net_hdr);
3090
3091 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
3092 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
3093 vi->any_header_sg = true;
3094
3095 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
3096 vi->has_cvq = true;
3097
3098 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
3099 mtu = virtio_cread16(vdev,
3100 offsetof(struct virtio_net_config,
3101 mtu));
3102 if (mtu < dev->min_mtu) {
3103 /* Should never trigger: MTU was previously validated
3104 * in virtnet_validate.
3105 */
3106 dev_err(&vdev->dev,
3107 "device MTU appears to have changed it is now %d < %d",
3108 mtu, dev->min_mtu);
3109 goto free;
3110 }
3111
3112 dev->mtu = mtu;
3113 dev->max_mtu = mtu;
3114
3115 /* TODO: size buffers correctly in this case. */
3116 if (dev->mtu > ETH_DATA_LEN)
3117 vi->big_packets = true;
3118 }
3119
3120 if (vi->any_header_sg)
3121 dev->needed_headroom = vi->hdr_len;
3122
3123 /* Enable multiqueue by default */
3124 if (num_online_cpus() >= max_queue_pairs)
3125 vi->curr_queue_pairs = max_queue_pairs;
3126 else
3127 vi->curr_queue_pairs = num_online_cpus();
3128 vi->max_queue_pairs = max_queue_pairs;
3129
3130 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
3131 err = init_vqs(vi);
3132 if (err)
3133 goto free;
3134
3135#ifdef CONFIG_SYSFS
3136 if (vi->mergeable_rx_bufs)
3137 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
3138#endif
3139 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
3140 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
3141
3142 virtnet_init_settings(dev);
3143
3144 if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
3145 vi->failover = net_failover_create(vi->dev);
3146 if (IS_ERR(vi->failover)) {
3147 err = PTR_ERR(vi->failover);
3148 goto free_vqs;
3149 }
3150 }
3151
3152 err = register_netdev(dev);
3153 if (err) {
3154 pr_debug("virtio_net: registering device failed\n");
3155 goto free_failover;
3156 }
3157
3158 virtio_device_ready(vdev);
3159
3160 err = virtnet_cpu_notif_add(vi);
3161 if (err) {
3162 pr_debug("virtio_net: registering cpu notifier failed\n");
3163 goto free_unregister_netdev;
3164 }
3165
3166 virtnet_set_queues(vi, vi->curr_queue_pairs);
3167
3168 /* Assume link up if device can't report link status,
3169 otherwise get link status from config. */
3170 netif_carrier_off(dev);
3171 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
3172 schedule_work(&vi->config_work);
3173 } else {
3174 vi->status = VIRTIO_NET_S_LINK_UP;
3175 virtnet_update_settings(vi);
3176 netif_carrier_on(dev);
3177 }
3178
3179 for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
3180 if (virtio_has_feature(vi->vdev, guest_offloads[i]))
3181 set_bit(guest_offloads[i], &vi->guest_offloads);
3182 vi->guest_offloads_capable = vi->guest_offloads;
3183
3184 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
3185 dev->name, max_queue_pairs);
3186
3187 return 0;
3188
3189free_unregister_netdev:
3190 vi->vdev->config->reset(vdev);
3191
3192 unregister_netdev(dev);
3193free_failover:
3194 net_failover_destroy(vi->failover);
3195free_vqs:
3196 cancel_delayed_work_sync(&vi->refill);
3197 free_receive_page_frags(vi);
3198 virtnet_del_vqs(vi);
3199free:
3200 free_netdev(dev);
3201 return err;
3202}
3203
3204static void remove_vq_common(struct virtnet_info *vi)
3205{
3206 vi->vdev->config->reset(vi->vdev);
3207
3208 /* Free unused buffers in both send and recv, if any. */
3209 free_unused_bufs(vi);
3210
3211 free_receive_bufs(vi);
3212
3213 free_receive_page_frags(vi);
3214
3215 virtnet_del_vqs(vi);
3216}
3217
3218static void virtnet_remove(struct virtio_device *vdev)
3219{
3220 struct virtnet_info *vi = vdev->priv;
3221
3222 virtnet_cpu_notif_remove(vi);
3223
3224 /* Make sure no work handler is accessing the device. */
3225 flush_work(&vi->config_work);
3226
3227 unregister_netdev(vi->dev);
3228
3229 net_failover_destroy(vi->failover);
3230
3231 remove_vq_common(vi);
3232
3233 free_netdev(vi->dev);
3234}
3235
3236static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
3237{
3238 struct virtnet_info *vi = vdev->priv;
3239
3240 virtnet_cpu_notif_remove(vi);
3241 virtnet_freeze_down(vdev);
3242 remove_vq_common(vi);
3243
3244 return 0;
3245}
3246
3247static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
3248{
3249 struct virtnet_info *vi = vdev->priv;
3250 int err;
3251
3252 err = virtnet_restore_up(vdev);
3253 if (err)
3254 return err;
3255 virtnet_set_queues(vi, vi->curr_queue_pairs);
3256
3257 err = virtnet_cpu_notif_add(vi);
3258 if (err)
3259 return err;
3260
3261 return 0;
3262}
3263
3264static struct virtio_device_id id_table[] = {
3265 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
3266 { 0 },
3267};
3268
3269#define VIRTNET_FEATURES \
3270 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
3271 VIRTIO_NET_F_MAC, \
3272 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
3273 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
3274 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
3275 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
3276 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
3277 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
3278 VIRTIO_NET_F_CTRL_MAC_ADDR, \
3279 VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
3280 VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY
3281
3282static unsigned int features[] = {
3283 VIRTNET_FEATURES,
3284};
3285
3286static unsigned int features_legacy[] = {
3287 VIRTNET_FEATURES,
3288 VIRTIO_NET_F_GSO,
3289 VIRTIO_F_ANY_LAYOUT,
3290};
3291
3292static struct virtio_driver virtio_net_driver = {
3293 .feature_table = features,
3294 .feature_table_size = ARRAY_SIZE(features),
3295 .feature_table_legacy = features_legacy,
3296 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
3297 .driver.name = KBUILD_MODNAME,
3298 .driver.owner = THIS_MODULE,
3299 .id_table = id_table,
3300 .validate = virtnet_validate,
3301 .probe = virtnet_probe,
3302 .remove = virtnet_remove,
3303 .config_changed = virtnet_config_changed,
3304#ifdef CONFIG_PM_SLEEP
3305 .freeze = virtnet_freeze,
3306 .restore = virtnet_restore,
3307#endif
3308};
3309
3310static __init int virtio_net_driver_init(void)
3311{
3312 int ret;
3313
3314 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
3315 virtnet_cpu_online,
3316 virtnet_cpu_down_prep);
3317 if (ret < 0)
3318 goto out;
3319 virtionet_online = ret;
3320 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
3321 NULL, virtnet_cpu_dead);
3322 if (ret)
3323 goto err_dead;
3324
3325 ret = register_virtio_driver(&virtio_net_driver);
3326 if (ret)
3327 goto err_virtio;
3328 return 0;
3329err_virtio:
3330 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
3331err_dead:
3332 cpuhp_remove_multi_state(virtionet_online);
3333out:
3334 return ret;
3335}
3336module_init(virtio_net_driver_init);
3337
3338static __exit void virtio_net_driver_exit(void)
3339{
3340 unregister_virtio_driver(&virtio_net_driver);
3341 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
3342 cpuhp_remove_multi_state(virtionet_online);
3343}
3344module_exit(virtio_net_driver_exit);
3345
3346MODULE_DEVICE_TABLE(virtio, id_table);
3347MODULE_DESCRIPTION("Virtio network driver");
3348MODULE_LICENSE("GPL");
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
33static int napi_weight = NAPI_POLL_WEIGHT;
34module_param(napi_weight, int, 0444);
35
36static bool csum = true, gso = true;
37module_param(csum, bool, 0444);
38module_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 */
49DECLARE_EWMA(pkt_len, 1, 64)
50
51/* With mergeable buffers we align buffer address and use the low bits to
52 * encode its true size. Buffer size is up to 1 page so we need to align to
53 * square root of page size to ensure we reserve enough bits to encode the true
54 * size.
55 */
56#define MERGEABLE_BUFFER_MIN_ALIGN_SHIFT ((PAGE_SHIFT + 1) / 2)
57
58/* Minimum alignment for mergeable packet buffers. */
59#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, \
60 1 << MERGEABLE_BUFFER_MIN_ALIGN_SHIFT)
61
62#define VIRTNET_DRIVER_VERSION "1.0.0"
63
64struct virtnet_stats {
65 struct u64_stats_sync tx_syncp;
66 struct u64_stats_sync rx_syncp;
67 u64 tx_bytes;
68 u64 tx_packets;
69
70 u64 rx_bytes;
71 u64 rx_packets;
72};
73
74/* Internal representation of a send virtqueue */
75struct send_queue {
76 /* Virtqueue associated with this send _queue */
77 struct virtqueue *vq;
78
79 /* TX: fragments + linear part + virtio header */
80 struct scatterlist sg[MAX_SKB_FRAGS + 2];
81
82 /* Name of the send queue: output.$index */
83 char name[40];
84};
85
86/* Internal representation of a receive virtqueue */
87struct receive_queue {
88 /* Virtqueue associated with this receive_queue */
89 struct virtqueue *vq;
90
91 struct napi_struct napi;
92
93 struct bpf_prog __rcu *xdp_prog;
94
95 /* Chain pages by the private ptr. */
96 struct page *pages;
97
98 /* Average packet length for mergeable receive buffers. */
99 struct ewma_pkt_len mrg_avg_pkt_len;
100
101 /* Page frag for packet buffer allocation. */
102 struct page_frag alloc_frag;
103
104 /* RX: fragments + linear part + virtio header */
105 struct scatterlist sg[MAX_SKB_FRAGS + 2];
106
107 /* Name of this receive queue: input.$index */
108 char name[40];
109};
110
111struct virtnet_info {
112 struct virtio_device *vdev;
113 struct virtqueue *cvq;
114 struct net_device *dev;
115 struct send_queue *sq;
116 struct receive_queue *rq;
117 unsigned int status;
118
119 /* Max # of queue pairs supported by the device */
120 u16 max_queue_pairs;
121
122 /* # of queue pairs currently used by the driver */
123 u16 curr_queue_pairs;
124
125 /* # of XDP queue pairs currently used by the driver */
126 u16 xdp_queue_pairs;
127
128 /* I like... big packets and I cannot lie! */
129 bool big_packets;
130
131 /* Host will merge rx buffers for big packets (shake it! shake it!) */
132 bool mergeable_rx_bufs;
133
134 /* Has control virtqueue */
135 bool has_cvq;
136
137 /* Host can handle any s/g split between our header and packet data */
138 bool any_header_sg;
139
140 /* Packet virtio header size */
141 u8 hdr_len;
142
143 /* Active statistics */
144 struct virtnet_stats __percpu *stats;
145
146 /* Work struct for refilling if we run low on memory. */
147 struct delayed_work refill;
148
149 /* Work struct for config space updates */
150 struct work_struct config_work;
151
152 /* Does the affinity hint is set for virtqueues? */
153 bool affinity_hint_set;
154
155 /* CPU hotplug instances for online & dead */
156 struct hlist_node node;
157 struct hlist_node node_dead;
158
159 /* Control VQ buffers: protected by the rtnl lock */
160 struct virtio_net_ctrl_hdr ctrl_hdr;
161 virtio_net_ctrl_ack ctrl_status;
162 struct virtio_net_ctrl_mq ctrl_mq;
163 u8 ctrl_promisc;
164 u8 ctrl_allmulti;
165 u16 ctrl_vid;
166
167 /* Ethtool settings */
168 u8 duplex;
169 u32 speed;
170};
171
172struct padded_vnet_hdr {
173 struct virtio_net_hdr_mrg_rxbuf hdr;
174 /*
175 * hdr is in a separate sg buffer, and data sg buffer shares same page
176 * with this header sg. This padding makes next sg 16 byte aligned
177 * after the header.
178 */
179 char padding[4];
180};
181
182/* Converting between virtqueue no. and kernel tx/rx queue no.
183 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
184 */
185static int vq2txq(struct virtqueue *vq)
186{
187 return (vq->index - 1) / 2;
188}
189
190static int txq2vq(int txq)
191{
192 return txq * 2 + 1;
193}
194
195static int vq2rxq(struct virtqueue *vq)
196{
197 return vq->index / 2;
198}
199
200static int rxq2vq(int rxq)
201{
202 return rxq * 2;
203}
204
205static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
206{
207 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
208}
209
210/*
211 * private is used to chain pages for big packets, put the whole
212 * most recent used list in the beginning for reuse
213 */
214static void give_pages(struct receive_queue *rq, struct page *page)
215{
216 struct page *end;
217
218 /* Find end of list, sew whole thing into vi->rq.pages. */
219 for (end = page; end->private; end = (struct page *)end->private);
220 end->private = (unsigned long)rq->pages;
221 rq->pages = page;
222}
223
224static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
225{
226 struct page *p = rq->pages;
227
228 if (p) {
229 rq->pages = (struct page *)p->private;
230 /* clear private here, it is used to chain pages */
231 p->private = 0;
232 } else
233 p = alloc_page(gfp_mask);
234 return p;
235}
236
237static void skb_xmit_done(struct virtqueue *vq)
238{
239 struct virtnet_info *vi = vq->vdev->priv;
240
241 /* Suppress further interrupts. */
242 virtqueue_disable_cb(vq);
243
244 /* We were probably waiting for more output buffers. */
245 netif_wake_subqueue(vi->dev, vq2txq(vq));
246}
247
248static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx)
249{
250 unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1);
251 return (truesize + 1) * MERGEABLE_BUFFER_ALIGN;
252}
253
254static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx)
255{
256 return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN);
257
258}
259
260static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize)
261{
262 unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN;
263 return (unsigned long)buf | (size - 1);
264}
265
266/* Called from bottom half context */
267static struct sk_buff *page_to_skb(struct virtnet_info *vi,
268 struct receive_queue *rq,
269 struct page *page, unsigned int offset,
270 unsigned int len, unsigned int truesize)
271{
272 struct sk_buff *skb;
273 struct virtio_net_hdr_mrg_rxbuf *hdr;
274 unsigned int copy, hdr_len, hdr_padded_len;
275 char *p;
276
277 p = page_address(page) + offset;
278
279 /* copy small packet so we can reuse these pages for small data */
280 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
281 if (unlikely(!skb))
282 return NULL;
283
284 hdr = skb_vnet_hdr(skb);
285
286 hdr_len = vi->hdr_len;
287 if (vi->mergeable_rx_bufs)
288 hdr_padded_len = sizeof *hdr;
289 else
290 hdr_padded_len = sizeof(struct padded_vnet_hdr);
291
292 memcpy(hdr, p, hdr_len);
293
294 len -= hdr_len;
295 offset += hdr_padded_len;
296 p += hdr_padded_len;
297
298 copy = len;
299 if (copy > skb_tailroom(skb))
300 copy = skb_tailroom(skb);
301 memcpy(skb_put(skb, copy), p, copy);
302
303 len -= copy;
304 offset += copy;
305
306 if (vi->mergeable_rx_bufs) {
307 if (len)
308 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
309 else
310 put_page(page);
311 return skb;
312 }
313
314 /*
315 * Verify that we can indeed put this data into a skb.
316 * This is here to handle cases when the device erroneously
317 * tries to receive more than is possible. This is usually
318 * the case of a broken device.
319 */
320 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
321 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
322 dev_kfree_skb(skb);
323 return NULL;
324 }
325 BUG_ON(offset >= PAGE_SIZE);
326 while (len) {
327 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
328 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
329 frag_size, truesize);
330 len -= frag_size;
331 page = (struct page *)page->private;
332 offset = 0;
333 }
334
335 if (page)
336 give_pages(rq, page);
337
338 return skb;
339}
340
341static void virtnet_xdp_xmit(struct virtnet_info *vi,
342 struct receive_queue *rq,
343 struct send_queue *sq,
344 struct xdp_buff *xdp,
345 void *data)
346{
347 struct virtio_net_hdr_mrg_rxbuf *hdr;
348 unsigned int num_sg, len;
349 void *xdp_sent;
350 int err;
351
352 /* Free up any pending old buffers before queueing new ones. */
353 while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) {
354 if (vi->mergeable_rx_bufs) {
355 struct page *sent_page = virt_to_head_page(xdp_sent);
356
357 put_page(sent_page);
358 } else { /* small buffer */
359 struct sk_buff *skb = xdp_sent;
360
361 kfree_skb(skb);
362 }
363 }
364
365 if (vi->mergeable_rx_bufs) {
366 /* Zero header and leave csum up to XDP layers */
367 hdr = xdp->data;
368 memset(hdr, 0, vi->hdr_len);
369
370 num_sg = 1;
371 sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data);
372 } else { /* small buffer */
373 struct sk_buff *skb = data;
374
375 /* Zero header and leave csum up to XDP layers */
376 hdr = skb_vnet_hdr(skb);
377 memset(hdr, 0, vi->hdr_len);
378
379 num_sg = 2;
380 sg_init_table(sq->sg, 2);
381 sg_set_buf(sq->sg, hdr, vi->hdr_len);
382 skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
383 }
384 err = virtqueue_add_outbuf(sq->vq, sq->sg, num_sg,
385 data, GFP_ATOMIC);
386 if (unlikely(err)) {
387 if (vi->mergeable_rx_bufs) {
388 struct page *page = virt_to_head_page(xdp->data);
389
390 put_page(page);
391 } else /* small buffer */
392 kfree_skb(data);
393 return; // On error abort to avoid unnecessary kick
394 }
395
396 virtqueue_kick(sq->vq);
397}
398
399static u32 do_xdp_prog(struct virtnet_info *vi,
400 struct receive_queue *rq,
401 struct bpf_prog *xdp_prog,
402 void *data, int len)
403{
404 int hdr_padded_len;
405 struct xdp_buff xdp;
406 void *buf;
407 unsigned int qp;
408 u32 act;
409
410 if (vi->mergeable_rx_bufs) {
411 hdr_padded_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
412 xdp.data = data + hdr_padded_len;
413 xdp.data_end = xdp.data + (len - vi->hdr_len);
414 buf = data;
415 } else { /* small buffers */
416 struct sk_buff *skb = data;
417
418 xdp.data = skb->data;
419 xdp.data_end = xdp.data + len;
420 buf = skb->data;
421 }
422
423 act = bpf_prog_run_xdp(xdp_prog, &xdp);
424 switch (act) {
425 case XDP_PASS:
426 return XDP_PASS;
427 case XDP_TX:
428 qp = vi->curr_queue_pairs -
429 vi->xdp_queue_pairs +
430 smp_processor_id();
431 xdp.data = buf;
432 virtnet_xdp_xmit(vi, rq, &vi->sq[qp], &xdp, data);
433 return XDP_TX;
434 default:
435 bpf_warn_invalid_xdp_action(act);
436 case XDP_ABORTED:
437 case XDP_DROP:
438 return XDP_DROP;
439 }
440}
441
442static struct sk_buff *receive_small(struct net_device *dev,
443 struct virtnet_info *vi,
444 struct receive_queue *rq,
445 void *buf, unsigned int len)
446{
447 struct sk_buff * skb = buf;
448 struct bpf_prog *xdp_prog;
449
450 len -= vi->hdr_len;
451 skb_trim(skb, len);
452
453 rcu_read_lock();
454 xdp_prog = rcu_dereference(rq->xdp_prog);
455 if (xdp_prog) {
456 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
457 u32 act;
458
459 if (unlikely(hdr->hdr.gso_type || hdr->hdr.flags))
460 goto err_xdp;
461 act = do_xdp_prog(vi, rq, xdp_prog, skb, len);
462 switch (act) {
463 case XDP_PASS:
464 break;
465 case XDP_TX:
466 rcu_read_unlock();
467 goto xdp_xmit;
468 case XDP_DROP:
469 default:
470 goto err_xdp;
471 }
472 }
473 rcu_read_unlock();
474
475 return skb;
476
477err_xdp:
478 rcu_read_unlock();
479 dev->stats.rx_dropped++;
480 kfree_skb(skb);
481xdp_xmit:
482 return NULL;
483}
484
485static struct sk_buff *receive_big(struct net_device *dev,
486 struct virtnet_info *vi,
487 struct receive_queue *rq,
488 void *buf,
489 unsigned int len)
490{
491 struct page *page = buf;
492 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
493
494 if (unlikely(!skb))
495 goto err;
496
497 return skb;
498
499err:
500 dev->stats.rx_dropped++;
501 give_pages(rq, page);
502 return NULL;
503}
504
505/* The conditions to enable XDP should preclude the underlying device from
506 * sending packets across multiple buffers (num_buf > 1). However per spec
507 * it does not appear to be illegal to do so but rather just against convention.
508 * So in order to avoid making a system unresponsive the packets are pushed
509 * into a page and the XDP program is run. This will be extremely slow and we
510 * push a warning to the user to fix this as soon as possible. Fixing this may
511 * require resolving the underlying hardware to determine why multiple buffers
512 * are being received or simply loading the XDP program in the ingress stack
513 * after the skb is built because there is no advantage to running it here
514 * anymore.
515 */
516static struct page *xdp_linearize_page(struct receive_queue *rq,
517 u16 *num_buf,
518 struct page *p,
519 int offset,
520 unsigned int *len)
521{
522 struct page *page = alloc_page(GFP_ATOMIC);
523 unsigned int page_off = 0;
524
525 if (!page)
526 return NULL;
527
528 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
529 page_off += *len;
530
531 while (--*num_buf) {
532 unsigned int buflen;
533 unsigned long ctx;
534 void *buf;
535 int off;
536
537 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &buflen);
538 if (unlikely(!ctx))
539 goto err_buf;
540
541 buf = mergeable_ctx_to_buf_address(ctx);
542 p = virt_to_head_page(buf);
543 off = buf - page_address(p);
544
545 /* guard against a misconfigured or uncooperative backend that
546 * is sending packet larger than the MTU.
547 */
548 if ((page_off + buflen) > PAGE_SIZE) {
549 put_page(p);
550 goto err_buf;
551 }
552
553 memcpy(page_address(page) + page_off,
554 page_address(p) + off, buflen);
555 page_off += buflen;
556 put_page(p);
557 }
558
559 *len = page_off;
560 return page;
561err_buf:
562 __free_pages(page, 0);
563 return NULL;
564}
565
566static struct sk_buff *receive_mergeable(struct net_device *dev,
567 struct virtnet_info *vi,
568 struct receive_queue *rq,
569 unsigned long ctx,
570 unsigned int len)
571{
572 void *buf = mergeable_ctx_to_buf_address(ctx);
573 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
574 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
575 struct page *page = virt_to_head_page(buf);
576 int offset = buf - page_address(page);
577 struct sk_buff *head_skb, *curr_skb;
578 struct bpf_prog *xdp_prog;
579 unsigned int truesize;
580
581 head_skb = NULL;
582
583 rcu_read_lock();
584 xdp_prog = rcu_dereference(rq->xdp_prog);
585 if (xdp_prog) {
586 struct page *xdp_page;
587 u32 act;
588
589 /* This happens when rx buffer size is underestimated */
590 if (unlikely(num_buf > 1)) {
591 /* linearize data for XDP */
592 xdp_page = xdp_linearize_page(rq, &num_buf,
593 page, offset, &len);
594 if (!xdp_page)
595 goto err_xdp;
596 offset = 0;
597 } else {
598 xdp_page = page;
599 }
600
601 /* Transient failure which in theory could occur if
602 * in-flight packets from before XDP was enabled reach
603 * the receive path after XDP is loaded. In practice I
604 * was not able to create this condition.
605 */
606 if (unlikely(hdr->hdr.gso_type))
607 goto err_xdp;
608
609 act = do_xdp_prog(vi, rq, xdp_prog,
610 page_address(xdp_page) + offset, len);
611 switch (act) {
612 case XDP_PASS:
613 /* We can only create skb based on xdp_page. */
614 if (unlikely(xdp_page != page)) {
615 rcu_read_unlock();
616 put_page(page);
617 head_skb = page_to_skb(vi, rq, xdp_page,
618 0, len, PAGE_SIZE);
619 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
620 return head_skb;
621 }
622 break;
623 case XDP_TX:
624 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
625 if (unlikely(xdp_page != page))
626 goto err_xdp;
627 rcu_read_unlock();
628 goto xdp_xmit;
629 case XDP_DROP:
630 default:
631 if (unlikely(xdp_page != page))
632 __free_pages(xdp_page, 0);
633 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
634 goto err_xdp;
635 }
636 }
637 rcu_read_unlock();
638
639 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
640 head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
641 curr_skb = head_skb;
642
643 if (unlikely(!curr_skb))
644 goto err_skb;
645 while (--num_buf) {
646 int num_skb_frags;
647
648 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
649 if (unlikely(!ctx)) {
650 pr_debug("%s: rx error: %d buffers out of %d missing\n",
651 dev->name, num_buf,
652 virtio16_to_cpu(vi->vdev,
653 hdr->num_buffers));
654 dev->stats.rx_length_errors++;
655 goto err_buf;
656 }
657
658 buf = mergeable_ctx_to_buf_address(ctx);
659 page = virt_to_head_page(buf);
660
661 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
662 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
663 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
664
665 if (unlikely(!nskb))
666 goto err_skb;
667 if (curr_skb == head_skb)
668 skb_shinfo(curr_skb)->frag_list = nskb;
669 else
670 curr_skb->next = nskb;
671 curr_skb = nskb;
672 head_skb->truesize += nskb->truesize;
673 num_skb_frags = 0;
674 }
675 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
676 if (curr_skb != head_skb) {
677 head_skb->data_len += len;
678 head_skb->len += len;
679 head_skb->truesize += truesize;
680 }
681 offset = buf - page_address(page);
682 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
683 put_page(page);
684 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
685 len, truesize);
686 } else {
687 skb_add_rx_frag(curr_skb, num_skb_frags, page,
688 offset, len, truesize);
689 }
690 }
691
692 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
693 return head_skb;
694
695err_xdp:
696 rcu_read_unlock();
697err_skb:
698 put_page(page);
699 while (--num_buf) {
700 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
701 if (unlikely(!ctx)) {
702 pr_debug("%s: rx error: %d buffers missing\n",
703 dev->name, num_buf);
704 dev->stats.rx_length_errors++;
705 break;
706 }
707 page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx));
708 put_page(page);
709 }
710err_buf:
711 dev->stats.rx_dropped++;
712 dev_kfree_skb(head_skb);
713xdp_xmit:
714 return NULL;
715}
716
717static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
718 void *buf, unsigned int len)
719{
720 struct net_device *dev = vi->dev;
721 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
722 struct sk_buff *skb;
723 struct virtio_net_hdr_mrg_rxbuf *hdr;
724
725 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
726 pr_debug("%s: short packet %i\n", dev->name, len);
727 dev->stats.rx_length_errors++;
728 if (vi->mergeable_rx_bufs) {
729 unsigned long ctx = (unsigned long)buf;
730 void *base = mergeable_ctx_to_buf_address(ctx);
731 put_page(virt_to_head_page(base));
732 } else if (vi->big_packets) {
733 give_pages(rq, buf);
734 } else {
735 dev_kfree_skb(buf);
736 }
737 return;
738 }
739
740 if (vi->mergeable_rx_bufs)
741 skb = receive_mergeable(dev, vi, rq, (unsigned long)buf, len);
742 else if (vi->big_packets)
743 skb = receive_big(dev, vi, rq, buf, len);
744 else
745 skb = receive_small(dev, vi, rq, buf, len);
746
747 if (unlikely(!skb))
748 return;
749
750 hdr = skb_vnet_hdr(skb);
751
752 u64_stats_update_begin(&stats->rx_syncp);
753 stats->rx_bytes += skb->len;
754 stats->rx_packets++;
755 u64_stats_update_end(&stats->rx_syncp);
756
757 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
758 skb->ip_summed = CHECKSUM_UNNECESSARY;
759
760 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
761 virtio_is_little_endian(vi->vdev))) {
762 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
763 dev->name, hdr->hdr.gso_type,
764 hdr->hdr.gso_size);
765 goto frame_err;
766 }
767
768 skb->protocol = eth_type_trans(skb, dev);
769 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
770 ntohs(skb->protocol), skb->len, skb->pkt_type);
771
772 napi_gro_receive(&rq->napi, skb);
773 return;
774
775frame_err:
776 dev->stats.rx_frame_errors++;
777 dev_kfree_skb(skb);
778}
779
780static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
781 gfp_t gfp)
782{
783 struct sk_buff *skb;
784 struct virtio_net_hdr_mrg_rxbuf *hdr;
785 int err;
786
787 skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp);
788 if (unlikely(!skb))
789 return -ENOMEM;
790
791 skb_put(skb, GOOD_PACKET_LEN);
792
793 hdr = skb_vnet_hdr(skb);
794 sg_init_table(rq->sg, 2);
795 sg_set_buf(rq->sg, hdr, vi->hdr_len);
796 skb_to_sgvec(skb, rq->sg + 1, 0, skb->len);
797
798 err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp);
799 if (err < 0)
800 dev_kfree_skb(skb);
801
802 return err;
803}
804
805static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
806 gfp_t gfp)
807{
808 struct page *first, *list = NULL;
809 char *p;
810 int i, err, offset;
811
812 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
813
814 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
815 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
816 first = get_a_page(rq, gfp);
817 if (!first) {
818 if (list)
819 give_pages(rq, list);
820 return -ENOMEM;
821 }
822 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
823
824 /* chain new page in list head to match sg */
825 first->private = (unsigned long)list;
826 list = first;
827 }
828
829 first = get_a_page(rq, gfp);
830 if (!first) {
831 give_pages(rq, list);
832 return -ENOMEM;
833 }
834 p = page_address(first);
835
836 /* rq->sg[0], rq->sg[1] share the same page */
837 /* a separated rq->sg[0] for header - required in case !any_header_sg */
838 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
839
840 /* rq->sg[1] for data packet, from offset */
841 offset = sizeof(struct padded_vnet_hdr);
842 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
843
844 /* chain first in list head */
845 first->private = (unsigned long)list;
846 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
847 first, gfp);
848 if (err < 0)
849 give_pages(rq, first);
850
851 return err;
852}
853
854static unsigned int get_mergeable_buf_len(struct ewma_pkt_len *avg_pkt_len)
855{
856 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
857 unsigned int len;
858
859 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
860 GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
861 return ALIGN(len, MERGEABLE_BUFFER_ALIGN);
862}
863
864static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
865{
866 struct page_frag *alloc_frag = &rq->alloc_frag;
867 char *buf;
868 unsigned long ctx;
869 int err;
870 unsigned int len, hole;
871
872 len = get_mergeable_buf_len(&rq->mrg_avg_pkt_len);
873 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
874 return -ENOMEM;
875
876 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
877 ctx = mergeable_buf_to_ctx(buf, len);
878 get_page(alloc_frag->page);
879 alloc_frag->offset += len;
880 hole = alloc_frag->size - alloc_frag->offset;
881 if (hole < len) {
882 /* To avoid internal fragmentation, if there is very likely not
883 * enough space for another buffer, add the remaining space to
884 * the current buffer. This extra space is not included in
885 * the truesize stored in ctx.
886 */
887 len += hole;
888 alloc_frag->offset += hole;
889 }
890
891 sg_init_one(rq->sg, buf, len);
892 err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, (void *)ctx, gfp);
893 if (err < 0)
894 put_page(virt_to_head_page(buf));
895
896 return err;
897}
898
899/*
900 * Returns false if we couldn't fill entirely (OOM).
901 *
902 * Normally run in the receive path, but can also be run from ndo_open
903 * before we're receiving packets, or from refill_work which is
904 * careful to disable receiving (using napi_disable).
905 */
906static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
907 gfp_t gfp)
908{
909 int err;
910 bool oom;
911
912 gfp |= __GFP_COLD;
913 do {
914 if (vi->mergeable_rx_bufs)
915 err = add_recvbuf_mergeable(rq, gfp);
916 else if (vi->big_packets)
917 err = add_recvbuf_big(vi, rq, gfp);
918 else
919 err = add_recvbuf_small(vi, rq, gfp);
920
921 oom = err == -ENOMEM;
922 if (err)
923 break;
924 } while (rq->vq->num_free);
925 virtqueue_kick(rq->vq);
926 return !oom;
927}
928
929static void skb_recv_done(struct virtqueue *rvq)
930{
931 struct virtnet_info *vi = rvq->vdev->priv;
932 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
933
934 /* Schedule NAPI, Suppress further interrupts if successful. */
935 if (napi_schedule_prep(&rq->napi)) {
936 virtqueue_disable_cb(rvq);
937 __napi_schedule(&rq->napi);
938 }
939}
940
941static void virtnet_napi_enable(struct receive_queue *rq)
942{
943 napi_enable(&rq->napi);
944
945 /* If all buffers were filled by other side before we napi_enabled, we
946 * won't get another interrupt, so process any outstanding packets
947 * now. virtnet_poll wants re-enable the queue, so we disable here.
948 * We synchronize against interrupts via NAPI_STATE_SCHED */
949 if (napi_schedule_prep(&rq->napi)) {
950 virtqueue_disable_cb(rq->vq);
951 local_bh_disable();
952 __napi_schedule(&rq->napi);
953 local_bh_enable();
954 }
955}
956
957static void refill_work(struct work_struct *work)
958{
959 struct virtnet_info *vi =
960 container_of(work, struct virtnet_info, refill.work);
961 bool still_empty;
962 int i;
963
964 for (i = 0; i < vi->curr_queue_pairs; i++) {
965 struct receive_queue *rq = &vi->rq[i];
966
967 napi_disable(&rq->napi);
968 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
969 virtnet_napi_enable(rq);
970
971 /* In theory, this can happen: if we don't get any buffers in
972 * we will *never* try to fill again.
973 */
974 if (still_empty)
975 schedule_delayed_work(&vi->refill, HZ/2);
976 }
977}
978
979static int virtnet_receive(struct receive_queue *rq, int budget)
980{
981 struct virtnet_info *vi = rq->vq->vdev->priv;
982 unsigned int len, received = 0;
983 void *buf;
984
985 while (received < budget &&
986 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
987 receive_buf(vi, rq, buf, len);
988 received++;
989 }
990
991 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
992 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
993 schedule_delayed_work(&vi->refill, 0);
994 }
995
996 return received;
997}
998
999static int virtnet_poll(struct napi_struct *napi, int budget)
1000{
1001 struct receive_queue *rq =
1002 container_of(napi, struct receive_queue, napi);
1003 unsigned int r, received;
1004
1005 received = virtnet_receive(rq, budget);
1006
1007 /* Out of packets? */
1008 if (received < budget) {
1009 r = virtqueue_enable_cb_prepare(rq->vq);
1010 napi_complete_done(napi, received);
1011 if (unlikely(virtqueue_poll(rq->vq, r)) &&
1012 napi_schedule_prep(napi)) {
1013 virtqueue_disable_cb(rq->vq);
1014 __napi_schedule(napi);
1015 }
1016 }
1017
1018 return received;
1019}
1020
1021#ifdef CONFIG_NET_RX_BUSY_POLL
1022/* must be called with local_bh_disable()d */
1023static int virtnet_busy_poll(struct napi_struct *napi)
1024{
1025 struct receive_queue *rq =
1026 container_of(napi, struct receive_queue, napi);
1027 struct virtnet_info *vi = rq->vq->vdev->priv;
1028 int r, received = 0, budget = 4;
1029
1030 if (!(vi->status & VIRTIO_NET_S_LINK_UP))
1031 return LL_FLUSH_FAILED;
1032
1033 if (!napi_schedule_prep(napi))
1034 return LL_FLUSH_BUSY;
1035
1036 virtqueue_disable_cb(rq->vq);
1037
1038again:
1039 received += virtnet_receive(rq, budget);
1040
1041 r = virtqueue_enable_cb_prepare(rq->vq);
1042 clear_bit(NAPI_STATE_SCHED, &napi->state);
1043 if (unlikely(virtqueue_poll(rq->vq, r)) &&
1044 napi_schedule_prep(napi)) {
1045 virtqueue_disable_cb(rq->vq);
1046 if (received < budget) {
1047 budget -= received;
1048 goto again;
1049 } else {
1050 __napi_schedule(napi);
1051 }
1052 }
1053
1054 return received;
1055}
1056#endif /* CONFIG_NET_RX_BUSY_POLL */
1057
1058static int virtnet_open(struct net_device *dev)
1059{
1060 struct virtnet_info *vi = netdev_priv(dev);
1061 int i;
1062
1063 for (i = 0; i < vi->max_queue_pairs; i++) {
1064 if (i < vi->curr_queue_pairs)
1065 /* Make sure we have some buffers: if oom use wq. */
1066 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1067 schedule_delayed_work(&vi->refill, 0);
1068 virtnet_napi_enable(&vi->rq[i]);
1069 }
1070
1071 return 0;
1072}
1073
1074static void free_old_xmit_skbs(struct send_queue *sq)
1075{
1076 struct sk_buff *skb;
1077 unsigned int len;
1078 struct virtnet_info *vi = sq->vq->vdev->priv;
1079 struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
1080
1081 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1082 pr_debug("Sent skb %p\n", skb);
1083
1084 u64_stats_update_begin(&stats->tx_syncp);
1085 stats->tx_bytes += skb->len;
1086 stats->tx_packets++;
1087 u64_stats_update_end(&stats->tx_syncp);
1088
1089 dev_kfree_skb_any(skb);
1090 }
1091}
1092
1093static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1094{
1095 struct virtio_net_hdr_mrg_rxbuf *hdr;
1096 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1097 struct virtnet_info *vi = sq->vq->vdev->priv;
1098 unsigned num_sg;
1099 unsigned hdr_len = vi->hdr_len;
1100 bool can_push;
1101
1102 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1103
1104 can_push = vi->any_header_sg &&
1105 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1106 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1107 /* Even if we can, don't push here yet as this would skew
1108 * csum_start offset below. */
1109 if (can_push)
1110 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1111 else
1112 hdr = skb_vnet_hdr(skb);
1113
1114 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1115 virtio_is_little_endian(vi->vdev), false))
1116 BUG();
1117
1118 if (vi->mergeable_rx_bufs)
1119 hdr->num_buffers = 0;
1120
1121 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1122 if (can_push) {
1123 __skb_push(skb, hdr_len);
1124 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1125 /* Pull header back to avoid skew in tx bytes calculations. */
1126 __skb_pull(skb, hdr_len);
1127 } else {
1128 sg_set_buf(sq->sg, hdr, hdr_len);
1129 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
1130 }
1131 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1132}
1133
1134static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1135{
1136 struct virtnet_info *vi = netdev_priv(dev);
1137 int qnum = skb_get_queue_mapping(skb);
1138 struct send_queue *sq = &vi->sq[qnum];
1139 int err;
1140 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1141 bool kick = !skb->xmit_more;
1142
1143 /* Free up any pending old buffers before queueing new ones. */
1144 free_old_xmit_skbs(sq);
1145
1146 /* timestamp packet in software */
1147 skb_tx_timestamp(skb);
1148
1149 /* Try to transmit */
1150 err = xmit_skb(sq, skb);
1151
1152 /* This should not happen! */
1153 if (unlikely(err)) {
1154 dev->stats.tx_fifo_errors++;
1155 if (net_ratelimit())
1156 dev_warn(&dev->dev,
1157 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
1158 dev->stats.tx_dropped++;
1159 dev_kfree_skb_any(skb);
1160 return NETDEV_TX_OK;
1161 }
1162
1163 /* Don't wait up for transmitted skbs to be freed. */
1164 skb_orphan(skb);
1165 nf_reset(skb);
1166
1167 /* If running out of space, stop queue to avoid getting packets that we
1168 * are then unable to transmit.
1169 * An alternative would be to force queuing layer to requeue the skb by
1170 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1171 * returned in a normal path of operation: it means that driver is not
1172 * maintaining the TX queue stop/start state properly, and causes
1173 * the stack to do a non-trivial amount of useless work.
1174 * Since most packets only take 1 or 2 ring slots, stopping the queue
1175 * early means 16 slots are typically wasted.
1176 */
1177 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1178 netif_stop_subqueue(dev, qnum);
1179 if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1180 /* More just got used, free them then recheck. */
1181 free_old_xmit_skbs(sq);
1182 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1183 netif_start_subqueue(dev, qnum);
1184 virtqueue_disable_cb(sq->vq);
1185 }
1186 }
1187 }
1188
1189 if (kick || netif_xmit_stopped(txq))
1190 virtqueue_kick(sq->vq);
1191
1192 return NETDEV_TX_OK;
1193}
1194
1195/*
1196 * Send command via the control virtqueue and check status. Commands
1197 * supported by the hypervisor, as indicated by feature bits, should
1198 * never fail unless improperly formatted.
1199 */
1200static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1201 struct scatterlist *out)
1202{
1203 struct scatterlist *sgs[4], hdr, stat;
1204 unsigned out_num = 0, tmp;
1205
1206 /* Caller should know better */
1207 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1208
1209 vi->ctrl_status = ~0;
1210 vi->ctrl_hdr.class = class;
1211 vi->ctrl_hdr.cmd = cmd;
1212 /* Add header */
1213 sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
1214 sgs[out_num++] = &hdr;
1215
1216 if (out)
1217 sgs[out_num++] = out;
1218
1219 /* Add return status. */
1220 sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
1221 sgs[out_num] = &stat;
1222
1223 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1224 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1225
1226 if (unlikely(!virtqueue_kick(vi->cvq)))
1227 return vi->ctrl_status == VIRTIO_NET_OK;
1228
1229 /* Spin for a response, the kick causes an ioport write, trapping
1230 * into the hypervisor, so the request should be handled immediately.
1231 */
1232 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1233 !virtqueue_is_broken(vi->cvq))
1234 cpu_relax();
1235
1236 return vi->ctrl_status == VIRTIO_NET_OK;
1237}
1238
1239static int virtnet_set_mac_address(struct net_device *dev, void *p)
1240{
1241 struct virtnet_info *vi = netdev_priv(dev);
1242 struct virtio_device *vdev = vi->vdev;
1243 int ret;
1244 struct sockaddr *addr;
1245 struct scatterlist sg;
1246
1247 addr = kmalloc(sizeof(*addr), GFP_KERNEL);
1248 if (!addr)
1249 return -ENOMEM;
1250 memcpy(addr, p, sizeof(*addr));
1251
1252 ret = eth_prepare_mac_addr_change(dev, addr);
1253 if (ret)
1254 goto out;
1255
1256 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1257 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1258 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1259 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1260 dev_warn(&vdev->dev,
1261 "Failed to set mac address by vq command.\n");
1262 ret = -EINVAL;
1263 goto out;
1264 }
1265 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1266 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1267 unsigned int i;
1268
1269 /* Naturally, this has an atomicity problem. */
1270 for (i = 0; i < dev->addr_len; i++)
1271 virtio_cwrite8(vdev,
1272 offsetof(struct virtio_net_config, mac) +
1273 i, addr->sa_data[i]);
1274 }
1275
1276 eth_commit_mac_addr_change(dev, p);
1277 ret = 0;
1278
1279out:
1280 kfree(addr);
1281 return ret;
1282}
1283
1284static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,
1285 struct rtnl_link_stats64 *tot)
1286{
1287 struct virtnet_info *vi = netdev_priv(dev);
1288 int cpu;
1289 unsigned int start;
1290
1291 for_each_possible_cpu(cpu) {
1292 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
1293 u64 tpackets, tbytes, rpackets, rbytes;
1294
1295 do {
1296 start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
1297 tpackets = stats->tx_packets;
1298 tbytes = stats->tx_bytes;
1299 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
1300
1301 do {
1302 start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
1303 rpackets = stats->rx_packets;
1304 rbytes = stats->rx_bytes;
1305 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
1306
1307 tot->rx_packets += rpackets;
1308 tot->tx_packets += tpackets;
1309 tot->rx_bytes += rbytes;
1310 tot->tx_bytes += tbytes;
1311 }
1312
1313 tot->tx_dropped = dev->stats.tx_dropped;
1314 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1315 tot->rx_dropped = dev->stats.rx_dropped;
1316 tot->rx_length_errors = dev->stats.rx_length_errors;
1317 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1318
1319 return tot;
1320}
1321
1322#ifdef CONFIG_NET_POLL_CONTROLLER
1323static void virtnet_netpoll(struct net_device *dev)
1324{
1325 struct virtnet_info *vi = netdev_priv(dev);
1326 int i;
1327
1328 for (i = 0; i < vi->curr_queue_pairs; i++)
1329 napi_schedule(&vi->rq[i].napi);
1330}
1331#endif
1332
1333static void virtnet_ack_link_announce(struct virtnet_info *vi)
1334{
1335 rtnl_lock();
1336 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1337 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1338 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1339 rtnl_unlock();
1340}
1341
1342static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1343{
1344 struct scatterlist sg;
1345 struct net_device *dev = vi->dev;
1346
1347 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1348 return 0;
1349
1350 vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1351 sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq));
1352
1353 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1354 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1355 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1356 queue_pairs);
1357 return -EINVAL;
1358 } else {
1359 vi->curr_queue_pairs = queue_pairs;
1360 /* virtnet_open() will refill when device is going to up. */
1361 if (dev->flags & IFF_UP)
1362 schedule_delayed_work(&vi->refill, 0);
1363 }
1364
1365 return 0;
1366}
1367
1368static int virtnet_close(struct net_device *dev)
1369{
1370 struct virtnet_info *vi = netdev_priv(dev);
1371 int i;
1372
1373 /* Make sure refill_work doesn't re-enable napi! */
1374 cancel_delayed_work_sync(&vi->refill);
1375
1376 for (i = 0; i < vi->max_queue_pairs; i++)
1377 napi_disable(&vi->rq[i].napi);
1378
1379 return 0;
1380}
1381
1382static void virtnet_set_rx_mode(struct net_device *dev)
1383{
1384 struct virtnet_info *vi = netdev_priv(dev);
1385 struct scatterlist sg[2];
1386 struct virtio_net_ctrl_mac *mac_data;
1387 struct netdev_hw_addr *ha;
1388 int uc_count;
1389 int mc_count;
1390 void *buf;
1391 int i;
1392
1393 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1394 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1395 return;
1396
1397 vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
1398 vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1399
1400 sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
1401
1402 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1403 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1404 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1405 vi->ctrl_promisc ? "en" : "dis");
1406
1407 sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
1408
1409 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1410 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1411 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1412 vi->ctrl_allmulti ? "en" : "dis");
1413
1414 uc_count = netdev_uc_count(dev);
1415 mc_count = netdev_mc_count(dev);
1416 /* MAC filter - use one buffer for both lists */
1417 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1418 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1419 mac_data = buf;
1420 if (!buf)
1421 return;
1422
1423 sg_init_table(sg, 2);
1424
1425 /* Store the unicast list and count in the front of the buffer */
1426 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1427 i = 0;
1428 netdev_for_each_uc_addr(ha, dev)
1429 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1430
1431 sg_set_buf(&sg[0], mac_data,
1432 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1433
1434 /* multicast list and count fill the end */
1435 mac_data = (void *)&mac_data->macs[uc_count][0];
1436
1437 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1438 i = 0;
1439 netdev_for_each_mc_addr(ha, dev)
1440 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1441
1442 sg_set_buf(&sg[1], mac_data,
1443 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1444
1445 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1446 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1447 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1448
1449 kfree(buf);
1450}
1451
1452static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1453 __be16 proto, u16 vid)
1454{
1455 struct virtnet_info *vi = netdev_priv(dev);
1456 struct scatterlist sg;
1457
1458 vi->ctrl_vid = vid;
1459 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1460
1461 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1462 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1463 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1464 return 0;
1465}
1466
1467static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1468 __be16 proto, u16 vid)
1469{
1470 struct virtnet_info *vi = netdev_priv(dev);
1471 struct scatterlist sg;
1472
1473 vi->ctrl_vid = vid;
1474 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
1475
1476 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1477 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1478 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1479 return 0;
1480}
1481
1482static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
1483{
1484 int i;
1485
1486 if (vi->affinity_hint_set) {
1487 for (i = 0; i < vi->max_queue_pairs; i++) {
1488 virtqueue_set_affinity(vi->rq[i].vq, -1);
1489 virtqueue_set_affinity(vi->sq[i].vq, -1);
1490 }
1491
1492 vi->affinity_hint_set = false;
1493 }
1494}
1495
1496static void virtnet_set_affinity(struct virtnet_info *vi)
1497{
1498 int i;
1499 int cpu;
1500
1501 /* In multiqueue mode, when the number of cpu is equal to the number of
1502 * queue pairs, we let the queue pairs to be private to one cpu by
1503 * setting the affinity hint to eliminate the contention.
1504 */
1505 if (vi->curr_queue_pairs == 1 ||
1506 vi->max_queue_pairs != num_online_cpus()) {
1507 virtnet_clean_affinity(vi, -1);
1508 return;
1509 }
1510
1511 i = 0;
1512 for_each_online_cpu(cpu) {
1513 virtqueue_set_affinity(vi->rq[i].vq, cpu);
1514 virtqueue_set_affinity(vi->sq[i].vq, cpu);
1515 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
1516 i++;
1517 }
1518
1519 vi->affinity_hint_set = true;
1520}
1521
1522static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1523{
1524 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1525 node);
1526 virtnet_set_affinity(vi);
1527 return 0;
1528}
1529
1530static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1531{
1532 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1533 node_dead);
1534 virtnet_set_affinity(vi);
1535 return 0;
1536}
1537
1538static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
1539{
1540 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1541 node);
1542
1543 virtnet_clean_affinity(vi, cpu);
1544 return 0;
1545}
1546
1547static enum cpuhp_state virtionet_online;
1548
1549static int virtnet_cpu_notif_add(struct virtnet_info *vi)
1550{
1551 int ret;
1552
1553 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
1554 if (ret)
1555 return ret;
1556 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1557 &vi->node_dead);
1558 if (!ret)
1559 return ret;
1560 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1561 return ret;
1562}
1563
1564static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
1565{
1566 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
1567 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
1568 &vi->node_dead);
1569}
1570
1571static void virtnet_get_ringparam(struct net_device *dev,
1572 struct ethtool_ringparam *ring)
1573{
1574 struct virtnet_info *vi = netdev_priv(dev);
1575
1576 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
1577 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
1578 ring->rx_pending = ring->rx_max_pending;
1579 ring->tx_pending = ring->tx_max_pending;
1580}
1581
1582
1583static void virtnet_get_drvinfo(struct net_device *dev,
1584 struct ethtool_drvinfo *info)
1585{
1586 struct virtnet_info *vi = netdev_priv(dev);
1587 struct virtio_device *vdev = vi->vdev;
1588
1589 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
1590 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
1591 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
1592
1593}
1594
1595/* TODO: Eliminate OOO packets during switching */
1596static int virtnet_set_channels(struct net_device *dev,
1597 struct ethtool_channels *channels)
1598{
1599 struct virtnet_info *vi = netdev_priv(dev);
1600 u16 queue_pairs = channels->combined_count;
1601 int err;
1602
1603 /* We don't support separate rx/tx channels.
1604 * We don't allow setting 'other' channels.
1605 */
1606 if (channels->rx_count || channels->tx_count || channels->other_count)
1607 return -EINVAL;
1608
1609 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
1610 return -EINVAL;
1611
1612 /* For now we don't support modifying channels while XDP is loaded
1613 * also when XDP is loaded all RX queues have XDP programs so we only
1614 * need to check a single RX queue.
1615 */
1616 if (vi->rq[0].xdp_prog)
1617 return -EINVAL;
1618
1619 get_online_cpus();
1620 err = virtnet_set_queues(vi, queue_pairs);
1621 if (!err) {
1622 netif_set_real_num_tx_queues(dev, queue_pairs);
1623 netif_set_real_num_rx_queues(dev, queue_pairs);
1624
1625 virtnet_set_affinity(vi);
1626 }
1627 put_online_cpus();
1628
1629 return err;
1630}
1631
1632static void virtnet_get_channels(struct net_device *dev,
1633 struct ethtool_channels *channels)
1634{
1635 struct virtnet_info *vi = netdev_priv(dev);
1636
1637 channels->combined_count = vi->curr_queue_pairs;
1638 channels->max_combined = vi->max_queue_pairs;
1639 channels->max_other = 0;
1640 channels->rx_count = 0;
1641 channels->tx_count = 0;
1642 channels->other_count = 0;
1643}
1644
1645/* Check if the user is trying to change anything besides speed/duplex */
1646static bool virtnet_validate_ethtool_cmd(const struct ethtool_cmd *cmd)
1647{
1648 struct ethtool_cmd diff1 = *cmd;
1649 struct ethtool_cmd diff2 = {};
1650
1651 /* cmd is always set so we need to clear it, validate the port type
1652 * and also without autonegotiation we can ignore advertising
1653 */
1654 ethtool_cmd_speed_set(&diff1, 0);
1655 diff2.port = PORT_OTHER;
1656 diff1.advertising = 0;
1657 diff1.duplex = 0;
1658 diff1.cmd = 0;
1659
1660 return !memcmp(&diff1, &diff2, sizeof(diff1));
1661}
1662
1663static int virtnet_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1664{
1665 struct virtnet_info *vi = netdev_priv(dev);
1666 u32 speed;
1667
1668 speed = ethtool_cmd_speed(cmd);
1669 /* don't allow custom speed and duplex */
1670 if (!ethtool_validate_speed(speed) ||
1671 !ethtool_validate_duplex(cmd->duplex) ||
1672 !virtnet_validate_ethtool_cmd(cmd))
1673 return -EINVAL;
1674 vi->speed = speed;
1675 vi->duplex = cmd->duplex;
1676
1677 return 0;
1678}
1679
1680static int virtnet_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1681{
1682 struct virtnet_info *vi = netdev_priv(dev);
1683
1684 ethtool_cmd_speed_set(cmd, vi->speed);
1685 cmd->duplex = vi->duplex;
1686 cmd->port = PORT_OTHER;
1687
1688 return 0;
1689}
1690
1691static void virtnet_init_settings(struct net_device *dev)
1692{
1693 struct virtnet_info *vi = netdev_priv(dev);
1694
1695 vi->speed = SPEED_UNKNOWN;
1696 vi->duplex = DUPLEX_UNKNOWN;
1697}
1698
1699static const struct ethtool_ops virtnet_ethtool_ops = {
1700 .get_drvinfo = virtnet_get_drvinfo,
1701 .get_link = ethtool_op_get_link,
1702 .get_ringparam = virtnet_get_ringparam,
1703 .set_channels = virtnet_set_channels,
1704 .get_channels = virtnet_get_channels,
1705 .get_ts_info = ethtool_op_get_ts_info,
1706 .get_settings = virtnet_get_settings,
1707 .set_settings = virtnet_set_settings,
1708};
1709
1710static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog)
1711{
1712 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
1713 struct virtnet_info *vi = netdev_priv(dev);
1714 struct bpf_prog *old_prog;
1715 u16 xdp_qp = 0, curr_qp;
1716 int i, err;
1717
1718 if (prog && prog->xdp_adjust_head) {
1719 netdev_warn(dev, "Does not support bpf_xdp_adjust_head()\n");
1720 return -EOPNOTSUPP;
1721 }
1722
1723 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1724 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1725 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
1726 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO)) {
1727 netdev_warn(dev, "can't set XDP while host is implementing LRO, disable LRO first\n");
1728 return -EOPNOTSUPP;
1729 }
1730
1731 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
1732 netdev_warn(dev, "XDP expects header/data in single page, any_header_sg required\n");
1733 return -EINVAL;
1734 }
1735
1736 if (dev->mtu > max_sz) {
1737 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
1738 return -EINVAL;
1739 }
1740
1741 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
1742 if (prog)
1743 xdp_qp = nr_cpu_ids;
1744
1745 /* XDP requires extra queues for XDP_TX */
1746 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
1747 netdev_warn(dev, "request %i queues but max is %i\n",
1748 curr_qp + xdp_qp, vi->max_queue_pairs);
1749 return -ENOMEM;
1750 }
1751
1752 err = virtnet_set_queues(vi, curr_qp + xdp_qp);
1753 if (err) {
1754 dev_warn(&dev->dev, "XDP Device queue allocation failure.\n");
1755 return err;
1756 }
1757
1758 if (prog) {
1759 prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
1760 if (IS_ERR(prog)) {
1761 virtnet_set_queues(vi, curr_qp);
1762 return PTR_ERR(prog);
1763 }
1764 }
1765
1766 vi->xdp_queue_pairs = xdp_qp;
1767 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
1768
1769 for (i = 0; i < vi->max_queue_pairs; i++) {
1770 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
1771 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
1772 if (old_prog)
1773 bpf_prog_put(old_prog);
1774 }
1775
1776 return 0;
1777}
1778
1779static bool virtnet_xdp_query(struct net_device *dev)
1780{
1781 struct virtnet_info *vi = netdev_priv(dev);
1782 int i;
1783
1784 for (i = 0; i < vi->max_queue_pairs; i++) {
1785 if (vi->rq[i].xdp_prog)
1786 return true;
1787 }
1788 return false;
1789}
1790
1791static int virtnet_xdp(struct net_device *dev, struct netdev_xdp *xdp)
1792{
1793 switch (xdp->command) {
1794 case XDP_SETUP_PROG:
1795 return virtnet_xdp_set(dev, xdp->prog);
1796 case XDP_QUERY_PROG:
1797 xdp->prog_attached = virtnet_xdp_query(dev);
1798 return 0;
1799 default:
1800 return -EINVAL;
1801 }
1802}
1803
1804static const struct net_device_ops virtnet_netdev = {
1805 .ndo_open = virtnet_open,
1806 .ndo_stop = virtnet_close,
1807 .ndo_start_xmit = start_xmit,
1808 .ndo_validate_addr = eth_validate_addr,
1809 .ndo_set_mac_address = virtnet_set_mac_address,
1810 .ndo_set_rx_mode = virtnet_set_rx_mode,
1811 .ndo_get_stats64 = virtnet_stats,
1812 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
1813 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
1814#ifdef CONFIG_NET_POLL_CONTROLLER
1815 .ndo_poll_controller = virtnet_netpoll,
1816#endif
1817#ifdef CONFIG_NET_RX_BUSY_POLL
1818 .ndo_busy_poll = virtnet_busy_poll,
1819#endif
1820 .ndo_xdp = virtnet_xdp,
1821};
1822
1823static void virtnet_config_changed_work(struct work_struct *work)
1824{
1825 struct virtnet_info *vi =
1826 container_of(work, struct virtnet_info, config_work);
1827 u16 v;
1828
1829 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
1830 struct virtio_net_config, status, &v) < 0)
1831 return;
1832
1833 if (v & VIRTIO_NET_S_ANNOUNCE) {
1834 netdev_notify_peers(vi->dev);
1835 virtnet_ack_link_announce(vi);
1836 }
1837
1838 /* Ignore unknown (future) status bits */
1839 v &= VIRTIO_NET_S_LINK_UP;
1840
1841 if (vi->status == v)
1842 return;
1843
1844 vi->status = v;
1845
1846 if (vi->status & VIRTIO_NET_S_LINK_UP) {
1847 netif_carrier_on(vi->dev);
1848 netif_tx_wake_all_queues(vi->dev);
1849 } else {
1850 netif_carrier_off(vi->dev);
1851 netif_tx_stop_all_queues(vi->dev);
1852 }
1853}
1854
1855static void virtnet_config_changed(struct virtio_device *vdev)
1856{
1857 struct virtnet_info *vi = vdev->priv;
1858
1859 schedule_work(&vi->config_work);
1860}
1861
1862static void virtnet_free_queues(struct virtnet_info *vi)
1863{
1864 int i;
1865
1866 for (i = 0; i < vi->max_queue_pairs; i++) {
1867 napi_hash_del(&vi->rq[i].napi);
1868 netif_napi_del(&vi->rq[i].napi);
1869 }
1870
1871 /* We called napi_hash_del() before netif_napi_del(),
1872 * we need to respect an RCU grace period before freeing vi->rq
1873 */
1874 synchronize_net();
1875
1876 kfree(vi->rq);
1877 kfree(vi->sq);
1878}
1879
1880static void free_receive_bufs(struct virtnet_info *vi)
1881{
1882 struct bpf_prog *old_prog;
1883 int i;
1884
1885 rtnl_lock();
1886 for (i = 0; i < vi->max_queue_pairs; i++) {
1887 while (vi->rq[i].pages)
1888 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
1889
1890 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
1891 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
1892 if (old_prog)
1893 bpf_prog_put(old_prog);
1894 }
1895 rtnl_unlock();
1896}
1897
1898static void free_receive_page_frags(struct virtnet_info *vi)
1899{
1900 int i;
1901 for (i = 0; i < vi->max_queue_pairs; i++)
1902 if (vi->rq[i].alloc_frag.page)
1903 put_page(vi->rq[i].alloc_frag.page);
1904}
1905
1906static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
1907{
1908 /* For small receive mode always use kfree_skb variants */
1909 if (!vi->mergeable_rx_bufs)
1910 return false;
1911
1912 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
1913 return false;
1914 else if (q < vi->curr_queue_pairs)
1915 return true;
1916 else
1917 return false;
1918}
1919
1920static void free_unused_bufs(struct virtnet_info *vi)
1921{
1922 void *buf;
1923 int i;
1924
1925 for (i = 0; i < vi->max_queue_pairs; i++) {
1926 struct virtqueue *vq = vi->sq[i].vq;
1927 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
1928 if (!is_xdp_raw_buffer_queue(vi, i))
1929 dev_kfree_skb(buf);
1930 else
1931 put_page(virt_to_head_page(buf));
1932 }
1933 }
1934
1935 for (i = 0; i < vi->max_queue_pairs; i++) {
1936 struct virtqueue *vq = vi->rq[i].vq;
1937
1938 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
1939 if (vi->mergeable_rx_bufs) {
1940 unsigned long ctx = (unsigned long)buf;
1941 void *base = mergeable_ctx_to_buf_address(ctx);
1942 put_page(virt_to_head_page(base));
1943 } else if (vi->big_packets) {
1944 give_pages(&vi->rq[i], buf);
1945 } else {
1946 dev_kfree_skb(buf);
1947 }
1948 }
1949 }
1950}
1951
1952static void virtnet_del_vqs(struct virtnet_info *vi)
1953{
1954 struct virtio_device *vdev = vi->vdev;
1955
1956 virtnet_clean_affinity(vi, -1);
1957
1958 vdev->config->del_vqs(vdev);
1959
1960 virtnet_free_queues(vi);
1961}
1962
1963static int virtnet_find_vqs(struct virtnet_info *vi)
1964{
1965 vq_callback_t **callbacks;
1966 struct virtqueue **vqs;
1967 int ret = -ENOMEM;
1968 int i, total_vqs;
1969 const char **names;
1970
1971 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
1972 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
1973 * possible control vq.
1974 */
1975 total_vqs = vi->max_queue_pairs * 2 +
1976 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
1977
1978 /* Allocate space for find_vqs parameters */
1979 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
1980 if (!vqs)
1981 goto err_vq;
1982 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
1983 if (!callbacks)
1984 goto err_callback;
1985 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
1986 if (!names)
1987 goto err_names;
1988
1989 /* Parameters for control virtqueue, if any */
1990 if (vi->has_cvq) {
1991 callbacks[total_vqs - 1] = NULL;
1992 names[total_vqs - 1] = "control";
1993 }
1994
1995 /* Allocate/initialize parameters for send/receive virtqueues */
1996 for (i = 0; i < vi->max_queue_pairs; i++) {
1997 callbacks[rxq2vq(i)] = skb_recv_done;
1998 callbacks[txq2vq(i)] = skb_xmit_done;
1999 sprintf(vi->rq[i].name, "input.%d", i);
2000 sprintf(vi->sq[i].name, "output.%d", i);
2001 names[rxq2vq(i)] = vi->rq[i].name;
2002 names[txq2vq(i)] = vi->sq[i].name;
2003 }
2004
2005 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2006 names);
2007 if (ret)
2008 goto err_find;
2009
2010 if (vi->has_cvq) {
2011 vi->cvq = vqs[total_vqs - 1];
2012 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2013 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2014 }
2015
2016 for (i = 0; i < vi->max_queue_pairs; i++) {
2017 vi->rq[i].vq = vqs[rxq2vq(i)];
2018 vi->sq[i].vq = vqs[txq2vq(i)];
2019 }
2020
2021 kfree(names);
2022 kfree(callbacks);
2023 kfree(vqs);
2024
2025 return 0;
2026
2027err_find:
2028 kfree(names);
2029err_names:
2030 kfree(callbacks);
2031err_callback:
2032 kfree(vqs);
2033err_vq:
2034 return ret;
2035}
2036
2037static int virtnet_alloc_queues(struct virtnet_info *vi)
2038{
2039 int i;
2040
2041 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
2042 if (!vi->sq)
2043 goto err_sq;
2044 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
2045 if (!vi->rq)
2046 goto err_rq;
2047
2048 INIT_DELAYED_WORK(&vi->refill, refill_work);
2049 for (i = 0; i < vi->max_queue_pairs; i++) {
2050 vi->rq[i].pages = NULL;
2051 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2052 napi_weight);
2053
2054 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2055 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2056 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2057 }
2058
2059 return 0;
2060
2061err_rq:
2062 kfree(vi->sq);
2063err_sq:
2064 return -ENOMEM;
2065}
2066
2067static int init_vqs(struct virtnet_info *vi)
2068{
2069 int ret;
2070
2071 /* Allocate send & receive queues */
2072 ret = virtnet_alloc_queues(vi);
2073 if (ret)
2074 goto err;
2075
2076 ret = virtnet_find_vqs(vi);
2077 if (ret)
2078 goto err_free;
2079
2080 get_online_cpus();
2081 virtnet_set_affinity(vi);
2082 put_online_cpus();
2083
2084 return 0;
2085
2086err_free:
2087 virtnet_free_queues(vi);
2088err:
2089 return ret;
2090}
2091
2092#ifdef CONFIG_SYSFS
2093static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2094 struct rx_queue_attribute *attribute, char *buf)
2095{
2096 struct virtnet_info *vi = netdev_priv(queue->dev);
2097 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2098 struct ewma_pkt_len *avg;
2099
2100 BUG_ON(queue_index >= vi->max_queue_pairs);
2101 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2102 return sprintf(buf, "%u\n", get_mergeable_buf_len(avg));
2103}
2104
2105static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2106 __ATTR_RO(mergeable_rx_buffer_size);
2107
2108static struct attribute *virtio_net_mrg_rx_attrs[] = {
2109 &mergeable_rx_buffer_size_attribute.attr,
2110 NULL
2111};
2112
2113static const struct attribute_group virtio_net_mrg_rx_group = {
2114 .name = "virtio_net",
2115 .attrs = virtio_net_mrg_rx_attrs
2116};
2117#endif
2118
2119static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2120 unsigned int fbit,
2121 const char *fname, const char *dname)
2122{
2123 if (!virtio_has_feature(vdev, fbit))
2124 return false;
2125
2126 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2127 fname, dname);
2128
2129 return true;
2130}
2131
2132#define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2133 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2134
2135static bool virtnet_validate_features(struct virtio_device *vdev)
2136{
2137 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2138 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2139 "VIRTIO_NET_F_CTRL_VQ") ||
2140 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2141 "VIRTIO_NET_F_CTRL_VQ") ||
2142 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2143 "VIRTIO_NET_F_CTRL_VQ") ||
2144 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2145 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2146 "VIRTIO_NET_F_CTRL_VQ"))) {
2147 return false;
2148 }
2149
2150 return true;
2151}
2152
2153#define MIN_MTU ETH_MIN_MTU
2154#define MAX_MTU ETH_MAX_MTU
2155
2156static int virtnet_probe(struct virtio_device *vdev)
2157{
2158 int i, err;
2159 struct net_device *dev;
2160 struct virtnet_info *vi;
2161 u16 max_queue_pairs;
2162 int mtu;
2163
2164 if (!vdev->config->get) {
2165 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2166 __func__);
2167 return -EINVAL;
2168 }
2169
2170 if (!virtnet_validate_features(vdev))
2171 return -EINVAL;
2172
2173 /* Find if host supports multiqueue virtio_net device */
2174 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2175 struct virtio_net_config,
2176 max_virtqueue_pairs, &max_queue_pairs);
2177
2178 /* We need at least 2 queue's */
2179 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2180 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2181 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2182 max_queue_pairs = 1;
2183
2184 /* Allocate ourselves a network device with room for our info */
2185 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2186 if (!dev)
2187 return -ENOMEM;
2188
2189 /* Set up network device as normal. */
2190 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2191 dev->netdev_ops = &virtnet_netdev;
2192 dev->features = NETIF_F_HIGHDMA;
2193
2194 dev->ethtool_ops = &virtnet_ethtool_ops;
2195 SET_NETDEV_DEV(dev, &vdev->dev);
2196
2197 /* Do we support "hardware" checksums? */
2198 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2199 /* This opens up the world of extra features. */
2200 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2201 if (csum)
2202 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2203
2204 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2205 dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
2206 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2207 }
2208 /* Individual feature bits: what can host handle? */
2209 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
2210 dev->hw_features |= NETIF_F_TSO;
2211 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
2212 dev->hw_features |= NETIF_F_TSO6;
2213 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
2214 dev->hw_features |= NETIF_F_TSO_ECN;
2215 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
2216 dev->hw_features |= NETIF_F_UFO;
2217
2218 dev->features |= NETIF_F_GSO_ROBUST;
2219
2220 if (gso)
2221 dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
2222 /* (!csum && gso) case will be fixed by register_netdev() */
2223 }
2224 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
2225 dev->features |= NETIF_F_RXCSUM;
2226
2227 dev->vlan_features = dev->features;
2228
2229 /* MTU range: 68 - 65535 */
2230 dev->min_mtu = MIN_MTU;
2231 dev->max_mtu = MAX_MTU;
2232
2233 /* Configuration may specify what MAC to use. Otherwise random. */
2234 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
2235 virtio_cread_bytes(vdev,
2236 offsetof(struct virtio_net_config, mac),
2237 dev->dev_addr, dev->addr_len);
2238 else
2239 eth_hw_addr_random(dev);
2240
2241 /* Set up our device-specific information */
2242 vi = netdev_priv(dev);
2243 vi->dev = dev;
2244 vi->vdev = vdev;
2245 vdev->priv = vi;
2246 vi->stats = alloc_percpu(struct virtnet_stats);
2247 err = -ENOMEM;
2248 if (vi->stats == NULL)
2249 goto free;
2250
2251 for_each_possible_cpu(i) {
2252 struct virtnet_stats *virtnet_stats;
2253 virtnet_stats = per_cpu_ptr(vi->stats, i);
2254 u64_stats_init(&virtnet_stats->tx_syncp);
2255 u64_stats_init(&virtnet_stats->rx_syncp);
2256 }
2257
2258 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
2259
2260 /* If we can receive ANY GSO packets, we must allocate large ones. */
2261 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2262 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2263 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
2264 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
2265 vi->big_packets = true;
2266
2267 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
2268 vi->mergeable_rx_bufs = true;
2269
2270 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
2271 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2272 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2273 else
2274 vi->hdr_len = sizeof(struct virtio_net_hdr);
2275
2276 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
2277 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
2278 vi->any_header_sg = true;
2279
2280 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2281 vi->has_cvq = true;
2282
2283 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2284 mtu = virtio_cread16(vdev,
2285 offsetof(struct virtio_net_config,
2286 mtu));
2287 if (mtu < dev->min_mtu) {
2288 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2289 } else {
2290 dev->mtu = mtu;
2291 dev->max_mtu = mtu;
2292 }
2293 }
2294
2295 if (vi->any_header_sg)
2296 dev->needed_headroom = vi->hdr_len;
2297
2298 /* Enable multiqueue by default */
2299 if (num_online_cpus() >= max_queue_pairs)
2300 vi->curr_queue_pairs = max_queue_pairs;
2301 else
2302 vi->curr_queue_pairs = num_online_cpus();
2303 vi->max_queue_pairs = max_queue_pairs;
2304
2305 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
2306 err = init_vqs(vi);
2307 if (err)
2308 goto free_stats;
2309
2310#ifdef CONFIG_SYSFS
2311 if (vi->mergeable_rx_bufs)
2312 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
2313#endif
2314 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
2315 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
2316
2317 virtnet_init_settings(dev);
2318
2319 err = register_netdev(dev);
2320 if (err) {
2321 pr_debug("virtio_net: registering device failed\n");
2322 goto free_vqs;
2323 }
2324
2325 virtio_device_ready(vdev);
2326
2327 err = virtnet_cpu_notif_add(vi);
2328 if (err) {
2329 pr_debug("virtio_net: registering cpu notifier failed\n");
2330 goto free_unregister_netdev;
2331 }
2332
2333 rtnl_lock();
2334 virtnet_set_queues(vi, vi->curr_queue_pairs);
2335 rtnl_unlock();
2336
2337 /* Assume link up if device can't report link status,
2338 otherwise get link status from config. */
2339 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
2340 netif_carrier_off(dev);
2341 schedule_work(&vi->config_work);
2342 } else {
2343 vi->status = VIRTIO_NET_S_LINK_UP;
2344 netif_carrier_on(dev);
2345 }
2346
2347 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
2348 dev->name, max_queue_pairs);
2349
2350 return 0;
2351
2352free_unregister_netdev:
2353 vi->vdev->config->reset(vdev);
2354
2355 unregister_netdev(dev);
2356free_vqs:
2357 cancel_delayed_work_sync(&vi->refill);
2358 free_receive_page_frags(vi);
2359 virtnet_del_vqs(vi);
2360free_stats:
2361 free_percpu(vi->stats);
2362free:
2363 free_netdev(dev);
2364 return err;
2365}
2366
2367static void remove_vq_common(struct virtnet_info *vi)
2368{
2369 vi->vdev->config->reset(vi->vdev);
2370
2371 /* Free unused buffers in both send and recv, if any. */
2372 free_unused_bufs(vi);
2373
2374 free_receive_bufs(vi);
2375
2376 free_receive_page_frags(vi);
2377
2378 virtnet_del_vqs(vi);
2379}
2380
2381static void virtnet_remove(struct virtio_device *vdev)
2382{
2383 struct virtnet_info *vi = vdev->priv;
2384
2385 virtnet_cpu_notif_remove(vi);
2386
2387 /* Make sure no work handler is accessing the device. */
2388 flush_work(&vi->config_work);
2389
2390 unregister_netdev(vi->dev);
2391
2392 remove_vq_common(vi);
2393
2394 free_percpu(vi->stats);
2395 free_netdev(vi->dev);
2396}
2397
2398#ifdef CONFIG_PM_SLEEP
2399static int virtnet_freeze(struct virtio_device *vdev)
2400{
2401 struct virtnet_info *vi = vdev->priv;
2402 int i;
2403
2404 virtnet_cpu_notif_remove(vi);
2405
2406 /* Make sure no work handler is accessing the device */
2407 flush_work(&vi->config_work);
2408
2409 netif_device_detach(vi->dev);
2410 cancel_delayed_work_sync(&vi->refill);
2411
2412 if (netif_running(vi->dev)) {
2413 for (i = 0; i < vi->max_queue_pairs; i++)
2414 napi_disable(&vi->rq[i].napi);
2415 }
2416
2417 remove_vq_common(vi);
2418
2419 return 0;
2420}
2421
2422static int virtnet_restore(struct virtio_device *vdev)
2423{
2424 struct virtnet_info *vi = vdev->priv;
2425 int err, i;
2426
2427 err = init_vqs(vi);
2428 if (err)
2429 return err;
2430
2431 virtio_device_ready(vdev);
2432
2433 if (netif_running(vi->dev)) {
2434 for (i = 0; i < vi->curr_queue_pairs; i++)
2435 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
2436 schedule_delayed_work(&vi->refill, 0);
2437
2438 for (i = 0; i < vi->max_queue_pairs; i++)
2439 virtnet_napi_enable(&vi->rq[i]);
2440 }
2441
2442 netif_device_attach(vi->dev);
2443
2444 rtnl_lock();
2445 virtnet_set_queues(vi, vi->curr_queue_pairs);
2446 rtnl_unlock();
2447
2448 err = virtnet_cpu_notif_add(vi);
2449 if (err)
2450 return err;
2451
2452 return 0;
2453}
2454#endif
2455
2456static struct virtio_device_id id_table[] = {
2457 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
2458 { 0 },
2459};
2460
2461#define VIRTNET_FEATURES \
2462 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
2463 VIRTIO_NET_F_MAC, \
2464 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
2465 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
2466 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
2467 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
2468 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
2469 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
2470 VIRTIO_NET_F_CTRL_MAC_ADDR, \
2471 VIRTIO_NET_F_MTU
2472
2473static unsigned int features[] = {
2474 VIRTNET_FEATURES,
2475};
2476
2477static unsigned int features_legacy[] = {
2478 VIRTNET_FEATURES,
2479 VIRTIO_NET_F_GSO,
2480 VIRTIO_F_ANY_LAYOUT,
2481};
2482
2483static struct virtio_driver virtio_net_driver = {
2484 .feature_table = features,
2485 .feature_table_size = ARRAY_SIZE(features),
2486 .feature_table_legacy = features_legacy,
2487 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
2488 .driver.name = KBUILD_MODNAME,
2489 .driver.owner = THIS_MODULE,
2490 .id_table = id_table,
2491 .probe = virtnet_probe,
2492 .remove = virtnet_remove,
2493 .config_changed = virtnet_config_changed,
2494#ifdef CONFIG_PM_SLEEP
2495 .freeze = virtnet_freeze,
2496 .restore = virtnet_restore,
2497#endif
2498};
2499
2500static __init int virtio_net_driver_init(void)
2501{
2502 int ret;
2503
2504 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
2505 virtnet_cpu_online,
2506 virtnet_cpu_down_prep);
2507 if (ret < 0)
2508 goto out;
2509 virtionet_online = ret;
2510 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
2511 NULL, virtnet_cpu_dead);
2512 if (ret)
2513 goto err_dead;
2514
2515 ret = register_virtio_driver(&virtio_net_driver);
2516 if (ret)
2517 goto err_virtio;
2518 return 0;
2519err_virtio:
2520 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2521err_dead:
2522 cpuhp_remove_multi_state(virtionet_online);
2523out:
2524 return ret;
2525}
2526module_init(virtio_net_driver_init);
2527
2528static __exit void virtio_net_driver_exit(void)
2529{
2530 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
2531 cpuhp_remove_multi_state(virtionet_online);
2532 unregister_virtio_driver(&virtio_net_driver);
2533}
2534module_exit(virtio_net_driver_exit);
2535
2536MODULE_DEVICE_TABLE(virtio, id_table);
2537MODULE_DESCRIPTION("Virtio network driver");
2538MODULE_LICENSE("GPL");