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dm writecache: add cond_resched to loop in persistent_memory_claim()
[linux/fpc-iii.git] / drivers / net / virtio_net.c
blobce07f52d89e7ab6f6df9e4141998d4dc912c15b9
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
26 static int napi_weight = NAPI_POLL_WEIGHT;
27 module_param(napi_weight, int, 0444);
28
29 static bool csum = true, gso = true, napi_tx = true;
30 module_param(csum, bool, 0444);
31 module_param(gso, bool, 0444);
32 module_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 */
54 DECLARE_EWMA(pkt_len, 0, 64)
55
56 #define VIRTNET_DRIVER_VERSION "1.0.0"
57
58 static 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
66 struct virtnet_stat_desc {
67 char desc[ETH_GSTRING_LEN];
68 size_t offset;
69 };
70
71 struct 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
80 struct 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
95 static 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
103 static 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 */
118 struct 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.$index */
126 char name[40];
127
128 struct virtnet_sq_stats stats;
129
130 struct napi_struct napi;
131 };
132
133 /* Internal representation of a receive virtqueue */
134 struct receive_queue {
135 /* Virtqueue associated with this receive_queue */
136 struct virtqueue *vq;
137
138 struct napi_struct napi;
139
140 struct bpf_prog __rcu *xdp_prog;
141
142 struct virtnet_rq_stats stats;
143
144 /* Chain pages by the private ptr. */
145 struct page *pages;
146
147 /* Average packet length for mergeable receive buffers. */
148 struct ewma_pkt_len mrg_avg_pkt_len;
149
150 /* Page frag for packet buffer allocation. */
151 struct page_frag alloc_frag;
152
153 /* RX: fragments + linear part + virtio header */
154 struct scatterlist sg[MAX_SKB_FRAGS + 2];
155
156 /* Min single buffer size for mergeable buffers case. */
157 unsigned int min_buf_len;
158
159 /* Name of this receive queue: input.$index */
160 char name[40];
161
162 struct xdp_rxq_info xdp_rxq;
163 };
164
165 /* Control VQ buffers: protected by the rtnl lock */
166 struct 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
176 struct 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
234 struct 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
244 static bool is_xdp_frame(void *ptr)
245 {
246 return (unsigned long)ptr & VIRTIO_XDP_FLAG;
247 }
248
249 static void *xdp_to_ptr(struct xdp_frame *ptr)
250 {
251 return (void *)((unsigned long)ptr | VIRTIO_XDP_FLAG);
252 }
253
254 static 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 */
262 static int vq2txq(struct virtqueue *vq)
263 {
264 return (vq->index - 1) / 2;
265 }
266
267 static int txq2vq(int txq)
268 {
269 return txq * 2 + 1;
270 }
271
272 static int vq2rxq(struct virtqueue *vq)
273 {
274 return vq->index / 2;
275 }
276
277 static int rxq2vq(int rxq)
278 {
279 return rxq * 2;
280 }
281
282 static 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 */
291 static 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
301 static 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
314 static 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
323 static 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
337 static 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
353 static 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
359 static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
360 {
361 return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
362 }
363
364 static 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 */
370 static 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, unsigned int metasize)
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 /* hdr_valid means no XDP, so we can copy the vnet header */
397 if (hdr_valid)
398 memcpy(hdr, p, hdr_len);
399
400 len -= hdr_len;
401 offset += hdr_padded_len;
402 p += hdr_padded_len;
403
404 copy = len;
405 if (copy > skb_tailroom(skb))
406 copy = skb_tailroom(skb);
407 skb_put_data(skb, p, copy);
408
409 if (metasize) {
410 __skb_pull(skb, metasize);
411 skb_metadata_set(skb, metasize);
412 }
413
414 len -= copy;
415 offset += copy;
416
417 if (vi->mergeable_rx_bufs) {
418 if (len)
419 skb_add_rx_frag(skb, 0, page, offset, len, truesize);
420 else
421 put_page(page);
422 return skb;
423 }
424
425 /*
426 * Verify that we can indeed put this data into a skb.
427 * This is here to handle cases when the device erroneously
428 * tries to receive more than is possible. This is usually
429 * the case of a broken device.
430 */
431 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
432 net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
433 dev_kfree_skb(skb);
434 return NULL;
435 }
436 BUG_ON(offset >= PAGE_SIZE);
437 while (len) {
438 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
439 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
440 frag_size, truesize);
441 len -= frag_size;
442 page = (struct page *)page->private;
443 offset = 0;
444 }
445
446 if (page)
447 give_pages(rq, page);
448
449 return skb;
450 }
451
452 static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
453 struct send_queue *sq,
454 struct xdp_frame *xdpf)
455 {
456 struct virtio_net_hdr_mrg_rxbuf *hdr;
457 int err;
458
459 if (unlikely(xdpf->headroom < vi->hdr_len))
460 return -EOVERFLOW;
461
462 /* Make room for virtqueue hdr (also change xdpf->headroom?) */
463 xdpf->data -= vi->hdr_len;
464 /* Zero header and leave csum up to XDP layers */
465 hdr = xdpf->data;
466 memset(hdr, 0, vi->hdr_len);
467 xdpf->len += vi->hdr_len;
468
469 sg_init_one(sq->sg, xdpf->data, xdpf->len);
470
471 err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp_to_ptr(xdpf),
472 GFP_ATOMIC);
473 if (unlikely(err))
474 return -ENOSPC; /* Caller handle free/refcnt */
475
476 return 0;
477 }
478
479 static struct send_queue *virtnet_xdp_sq(struct virtnet_info *vi)
480 {
481 unsigned int qp;
482
483 qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
484 return &vi->sq[qp];
485 }
486
487 static int virtnet_xdp_xmit(struct net_device *dev,
488 int n, struct xdp_frame **frames, u32 flags)
489 {
490 struct virtnet_info *vi = netdev_priv(dev);
491 struct receive_queue *rq = vi->rq;
492 struct bpf_prog *xdp_prog;
493 struct send_queue *sq;
494 unsigned int len;
495 int packets = 0;
496 int bytes = 0;
497 int drops = 0;
498 int kicks = 0;
499 int ret, err;
500 void *ptr;
501 int i;
502
503 /* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this
504 * indicate XDP resources have been successfully allocated.
505 */
506 xdp_prog = rcu_access_pointer(rq->xdp_prog);
507 if (!xdp_prog)
508 return -ENXIO;
509
510 sq = virtnet_xdp_sq(vi);
511
512 if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
513 ret = -EINVAL;
514 drops = n;
515 goto out;
516 }
517
518 /* Free up any pending old buffers before queueing new ones. */
519 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
520 if (likely(is_xdp_frame(ptr))) {
521 struct xdp_frame *frame = ptr_to_xdp(ptr);
522
523 bytes += frame->len;
524 xdp_return_frame(frame);
525 } else {
526 struct sk_buff *skb = ptr;
527
528 bytes += skb->len;
529 napi_consume_skb(skb, false);
530 }
531 packets++;
532 }
533
534 for (i = 0; i < n; i++) {
535 struct xdp_frame *xdpf = frames[i];
536
537 err = __virtnet_xdp_xmit_one(vi, sq, xdpf);
538 if (err) {
539 xdp_return_frame_rx_napi(xdpf);
540 drops++;
541 }
542 }
543 ret = n - drops;
544
545 if (flags & XDP_XMIT_FLUSH) {
546 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
547 kicks = 1;
548 }
549 out:
550 u64_stats_update_begin(&sq->stats.syncp);
551 sq->stats.bytes += bytes;
552 sq->stats.packets += packets;
553 sq->stats.xdp_tx += n;
554 sq->stats.xdp_tx_drops += drops;
555 sq->stats.kicks += kicks;
556 u64_stats_update_end(&sq->stats.syncp);
557
558 return ret;
559 }
560
561 static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
562 {
563 return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
564 }
565
566 /* We copy the packet for XDP in the following cases:
567 *
568 * 1) Packet is scattered across multiple rx buffers.
569 * 2) Headroom space is insufficient.
570 *
571 * This is inefficient but it's a temporary condition that
572 * we hit right after XDP is enabled and until queue is refilled
573 * with large buffers with sufficient headroom - so it should affect
574 * at most queue size packets.
575 * Afterwards, the conditions to enable
576 * XDP should preclude the underlying device from sending packets
577 * across multiple buffers (num_buf > 1), and we make sure buffers
578 * have enough headroom.
579 */
580 static struct page *xdp_linearize_page(struct receive_queue *rq,
581 u16 *num_buf,
582 struct page *p,
583 int offset,
584 int page_off,
585 unsigned int *len)
586 {
587 struct page *page = alloc_page(GFP_ATOMIC);
588
589 if (!page)
590 return NULL;
591
592 memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
593 page_off += *len;
594
595 while (--*num_buf) {
596 int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
597 unsigned int buflen;
598 void *buf;
599 int off;
600
601 buf = virtqueue_get_buf(rq->vq, &buflen);
602 if (unlikely(!buf))
603 goto err_buf;
604
605 p = virt_to_head_page(buf);
606 off = buf - page_address(p);
607
608 /* guard against a misconfigured or uncooperative backend that
609 * is sending packet larger than the MTU.
610 */
611 if ((page_off + buflen + tailroom) > PAGE_SIZE) {
612 put_page(p);
613 goto err_buf;
614 }
615
616 memcpy(page_address(page) + page_off,
617 page_address(p) + off, buflen);
618 page_off += buflen;
619 put_page(p);
620 }
621
622 /* Headroom does not contribute to packet length */
623 *len = page_off - VIRTIO_XDP_HEADROOM;
624 return page;
625 err_buf:
626 __free_pages(page, 0);
627 return NULL;
628 }
629
630 static struct sk_buff *receive_small(struct net_device *dev,
631 struct virtnet_info *vi,
632 struct receive_queue *rq,
633 void *buf, void *ctx,
634 unsigned int len,
635 unsigned int *xdp_xmit,
636 struct virtnet_rq_stats *stats)
637 {
638 struct sk_buff *skb;
639 struct bpf_prog *xdp_prog;
640 unsigned int xdp_headroom = (unsigned long)ctx;
641 unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
642 unsigned int headroom = vi->hdr_len + header_offset;
643 unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
644 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
645 struct page *page = virt_to_head_page(buf);
646 unsigned int delta = 0;
647 struct page *xdp_page;
648 int err;
649 unsigned int metasize = 0;
650
651 len -= vi->hdr_len;
652 stats->bytes += len;
653
654 rcu_read_lock();
655 xdp_prog = rcu_dereference(rq->xdp_prog);
656 if (xdp_prog) {
657 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
658 struct xdp_frame *xdpf;
659 struct xdp_buff xdp;
660 void *orig_data;
661 u32 act;
662
663 if (unlikely(hdr->hdr.gso_type))
664 goto err_xdp;
665
666 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
667 int offset = buf - page_address(page) + header_offset;
668 unsigned int tlen = len + vi->hdr_len;
669 u16 num_buf = 1;
670
671 xdp_headroom = virtnet_get_headroom(vi);
672 header_offset = VIRTNET_RX_PAD + xdp_headroom;
673 headroom = vi->hdr_len + header_offset;
674 buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
675 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
676 xdp_page = xdp_linearize_page(rq, &num_buf, page,
677 offset, header_offset,
678 &tlen);
679 if (!xdp_page)
680 goto err_xdp;
681
682 buf = page_address(xdp_page);
683 put_page(page);
684 page = xdp_page;
685 }
686
687 xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
688 xdp.data = xdp.data_hard_start + xdp_headroom;
689 xdp.data_end = xdp.data + len;
690 xdp.data_meta = xdp.data;
691 xdp.rxq = &rq->xdp_rxq;
692 orig_data = xdp.data;
693 act = bpf_prog_run_xdp(xdp_prog, &xdp);
694 stats->xdp_packets++;
695
696 switch (act) {
697 case XDP_PASS:
698 /* Recalculate length in case bpf program changed it */
699 delta = orig_data - xdp.data;
700 len = xdp.data_end - xdp.data;
701 metasize = xdp.data - xdp.data_meta;
702 break;
703 case XDP_TX:
704 stats->xdp_tx++;
705 xdpf = convert_to_xdp_frame(&xdp);
706 if (unlikely(!xdpf))
707 goto err_xdp;
708 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
709 if (unlikely(err < 0)) {
710 trace_xdp_exception(vi->dev, xdp_prog, act);
711 goto err_xdp;
712 }
713 *xdp_xmit |= VIRTIO_XDP_TX;
714 rcu_read_unlock();
715 goto xdp_xmit;
716 case XDP_REDIRECT:
717 stats->xdp_redirects++;
718 err = xdp_do_redirect(dev, &xdp, xdp_prog);
719 if (err)
720 goto err_xdp;
721 *xdp_xmit |= VIRTIO_XDP_REDIR;
722 rcu_read_unlock();
723 goto xdp_xmit;
724 default:
725 bpf_warn_invalid_xdp_action(act);
726 /* fall through */
727 case XDP_ABORTED:
728 trace_xdp_exception(vi->dev, xdp_prog, act);
729 case XDP_DROP:
730 goto err_xdp;
731 }
732 }
733 rcu_read_unlock();
734
735 skb = build_skb(buf, buflen);
736 if (!skb) {
737 put_page(page);
738 goto err;
739 }
740 skb_reserve(skb, headroom - delta);
741 skb_put(skb, len);
742 if (!xdp_prog) {
743 buf += header_offset;
744 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
745 } /* keep zeroed vnet hdr since XDP is loaded */
746
747 if (metasize)
748 skb_metadata_set(skb, metasize);
749
750 err:
751 return skb;
752
753 err_xdp:
754 rcu_read_unlock();
755 stats->xdp_drops++;
756 stats->drops++;
757 put_page(page);
758 xdp_xmit:
759 return NULL;
760 }
761
762 static struct sk_buff *receive_big(struct net_device *dev,
763 struct virtnet_info *vi,
764 struct receive_queue *rq,
765 void *buf,
766 unsigned int len,
767 struct virtnet_rq_stats *stats)
768 {
769 struct page *page = buf;
770 struct sk_buff *skb =
771 page_to_skb(vi, rq, page, 0, len, PAGE_SIZE, true, 0);
772
773 stats->bytes += len - vi->hdr_len;
774 if (unlikely(!skb))
775 goto err;
776
777 return skb;
778
779 err:
780 stats->drops++;
781 give_pages(rq, page);
782 return NULL;
783 }
784
785 static struct sk_buff *receive_mergeable(struct net_device *dev,
786 struct virtnet_info *vi,
787 struct receive_queue *rq,
788 void *buf,
789 void *ctx,
790 unsigned int len,
791 unsigned int *xdp_xmit,
792 struct virtnet_rq_stats *stats)
793 {
794 struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
795 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
796 struct page *page = virt_to_head_page(buf);
797 int offset = buf - page_address(page);
798 struct sk_buff *head_skb, *curr_skb;
799 struct bpf_prog *xdp_prog;
800 unsigned int truesize;
801 unsigned int headroom = mergeable_ctx_to_headroom(ctx);
802 int err;
803 unsigned int metasize = 0;
804
805 head_skb = NULL;
806 stats->bytes += len - vi->hdr_len;
807
808 rcu_read_lock();
809 xdp_prog = rcu_dereference(rq->xdp_prog);
810 if (xdp_prog) {
811 struct xdp_frame *xdpf;
812 struct page *xdp_page;
813 struct xdp_buff xdp;
814 void *data;
815 u32 act;
816
817 /* Transient failure which in theory could occur if
818 * in-flight packets from before XDP was enabled reach
819 * the receive path after XDP is loaded.
820 */
821 if (unlikely(hdr->hdr.gso_type))
822 goto err_xdp;
823
824 /* This happens when rx buffer size is underestimated
825 * or headroom is not enough because of the buffer
826 * was refilled before XDP is set. This should only
827 * happen for the first several packets, so we don't
828 * care much about its performance.
829 */
830 if (unlikely(num_buf > 1 ||
831 headroom < virtnet_get_headroom(vi))) {
832 /* linearize data for XDP */
833 xdp_page = xdp_linearize_page(rq, &num_buf,
834 page, offset,
835 VIRTIO_XDP_HEADROOM,
836 &len);
837 if (!xdp_page)
838 goto err_xdp;
839 offset = VIRTIO_XDP_HEADROOM;
840 } else {
841 xdp_page = page;
842 }
843
844 /* Allow consuming headroom but reserve enough space to push
845 * the descriptor on if we get an XDP_TX return code.
846 */
847 data = page_address(xdp_page) + offset;
848 xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
849 xdp.data = data + vi->hdr_len;
850 xdp.data_end = xdp.data + (len - vi->hdr_len);
851 xdp.data_meta = xdp.data;
852 xdp.rxq = &rq->xdp_rxq;
853
854 act = bpf_prog_run_xdp(xdp_prog, &xdp);
855 stats->xdp_packets++;
856
857 switch (act) {
858 case XDP_PASS:
859 metasize = xdp.data - xdp.data_meta;
860
861 /* recalculate offset to account for any header
862 * adjustments and minus the metasize to copy the
863 * metadata in page_to_skb(). Note other cases do not
864 * build an skb and avoid using offset
865 */
866 offset = xdp.data - page_address(xdp_page) -
867 vi->hdr_len - metasize;
868
869 /* recalculate len if xdp.data, xdp.data_end or
870 * xdp.data_meta were adjusted
871 */
872 len = xdp.data_end - xdp.data + vi->hdr_len + metasize;
873 /* We can only create skb based on xdp_page. */
874 if (unlikely(xdp_page != page)) {
875 rcu_read_unlock();
876 put_page(page);
877 head_skb = page_to_skb(vi, rq, xdp_page, offset,
878 len, PAGE_SIZE, false,
879 metasize);
880 return head_skb;
881 }
882 break;
883 case XDP_TX:
884 stats->xdp_tx++;
885 xdpf = convert_to_xdp_frame(&xdp);
886 if (unlikely(!xdpf))
887 goto err_xdp;
888 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
889 if (unlikely(err < 0)) {
890 trace_xdp_exception(vi->dev, xdp_prog, act);
891 if (unlikely(xdp_page != page))
892 put_page(xdp_page);
893 goto err_xdp;
894 }
895 *xdp_xmit |= VIRTIO_XDP_TX;
896 if (unlikely(xdp_page != page))
897 put_page(page);
898 rcu_read_unlock();
899 goto xdp_xmit;
900 case XDP_REDIRECT:
901 stats->xdp_redirects++;
902 err = xdp_do_redirect(dev, &xdp, xdp_prog);
903 if (err) {
904 if (unlikely(xdp_page != page))
905 put_page(xdp_page);
906 goto err_xdp;
907 }
908 *xdp_xmit |= VIRTIO_XDP_REDIR;
909 if (unlikely(xdp_page != page))
910 put_page(page);
911 rcu_read_unlock();
912 goto xdp_xmit;
913 default:
914 bpf_warn_invalid_xdp_action(act);
915 /* fall through */
916 case XDP_ABORTED:
917 trace_xdp_exception(vi->dev, xdp_prog, act);
918 /* fall through */
919 case XDP_DROP:
920 if (unlikely(xdp_page != page))
921 __free_pages(xdp_page, 0);
922 goto err_xdp;
923 }
924 }
925 rcu_read_unlock();
926
927 truesize = mergeable_ctx_to_truesize(ctx);
928 if (unlikely(len > truesize)) {
929 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
930 dev->name, len, (unsigned long)ctx);
931 dev->stats.rx_length_errors++;
932 goto err_skb;
933 }
934
935 head_skb = page_to_skb(vi, rq, page, offset, len, truesize, !xdp_prog,
936 metasize);
937 curr_skb = head_skb;
938
939 if (unlikely(!curr_skb))
940 goto err_skb;
941 while (--num_buf) {
942 int num_skb_frags;
943
944 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx);
945 if (unlikely(!buf)) {
946 pr_debug("%s: rx error: %d buffers out of %d missing\n",
947 dev->name, num_buf,
948 virtio16_to_cpu(vi->vdev,
949 hdr->num_buffers));
950 dev->stats.rx_length_errors++;
951 goto err_buf;
952 }
953
954 stats->bytes += len;
955 page = virt_to_head_page(buf);
956
957 truesize = mergeable_ctx_to_truesize(ctx);
958 if (unlikely(len > truesize)) {
959 pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
960 dev->name, len, (unsigned long)ctx);
961 dev->stats.rx_length_errors++;
962 goto err_skb;
963 }
964
965 num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
966 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
967 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
968
969 if (unlikely(!nskb))
970 goto err_skb;
971 if (curr_skb == head_skb)
972 skb_shinfo(curr_skb)->frag_list = nskb;
973 else
974 curr_skb->next = nskb;
975 curr_skb = nskb;
976 head_skb->truesize += nskb->truesize;
977 num_skb_frags = 0;
978 }
979 if (curr_skb != head_skb) {
980 head_skb->data_len += len;
981 head_skb->len += len;
982 head_skb->truesize += truesize;
983 }
984 offset = buf - page_address(page);
985 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
986 put_page(page);
987 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
988 len, truesize);
989 } else {
990 skb_add_rx_frag(curr_skb, num_skb_frags, page,
991 offset, len, truesize);
992 }
993 }
994
995 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
996 return head_skb;
997
998 err_xdp:
999 rcu_read_unlock();
1000 stats->xdp_drops++;
1001 err_skb:
1002 put_page(page);
1003 while (num_buf-- > 1) {
1004 buf = virtqueue_get_buf(rq->vq, &len);
1005 if (unlikely(!buf)) {
1006 pr_debug("%s: rx error: %d buffers missing\n",
1007 dev->name, num_buf);
1008 dev->stats.rx_length_errors++;
1009 break;
1010 }
1011 stats->bytes += len;
1012 page = virt_to_head_page(buf);
1013 put_page(page);
1014 }
1015 err_buf:
1016 stats->drops++;
1017 dev_kfree_skb(head_skb);
1018 xdp_xmit:
1019 return NULL;
1020 }
1021
1022 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
1023 void *buf, unsigned int len, void **ctx,
1024 unsigned int *xdp_xmit,
1025 struct virtnet_rq_stats *stats)
1026 {
1027 struct net_device *dev = vi->dev;
1028 struct sk_buff *skb;
1029 struct virtio_net_hdr_mrg_rxbuf *hdr;
1030
1031 if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
1032 pr_debug("%s: short packet %i\n", dev->name, len);
1033 dev->stats.rx_length_errors++;
1034 if (vi->mergeable_rx_bufs) {
1035 put_page(virt_to_head_page(buf));
1036 } else if (vi->big_packets) {
1037 give_pages(rq, buf);
1038 } else {
1039 put_page(virt_to_head_page(buf));
1040 }
1041 return;
1042 }
1043
1044 if (vi->mergeable_rx_bufs)
1045 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit,
1046 stats);
1047 else if (vi->big_packets)
1048 skb = receive_big(dev, vi, rq, buf, len, stats);
1049 else
1050 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats);
1051
1052 if (unlikely(!skb))
1053 return;
1054
1055 hdr = skb_vnet_hdr(skb);
1056
1057 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
1058 skb->ip_summed = CHECKSUM_UNNECESSARY;
1059
1060 if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
1061 virtio_is_little_endian(vi->vdev))) {
1062 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
1063 dev->name, hdr->hdr.gso_type,
1064 hdr->hdr.gso_size);
1065 goto frame_err;
1066 }
1067
1068 skb_record_rx_queue(skb, vq2rxq(rq->vq));
1069 skb->protocol = eth_type_trans(skb, dev);
1070 pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
1071 ntohs(skb->protocol), skb->len, skb->pkt_type);
1072
1073 napi_gro_receive(&rq->napi, skb);
1074 return;
1075
1076 frame_err:
1077 dev->stats.rx_frame_errors++;
1078 dev_kfree_skb(skb);
1079 }
1080
1081 /* Unlike mergeable buffers, all buffers are allocated to the
1082 * same size, except for the headroom. For this reason we do
1083 * not need to use mergeable_len_to_ctx here - it is enough
1084 * to store the headroom as the context ignoring the truesize.
1085 */
1086 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
1087 gfp_t gfp)
1088 {
1089 struct page_frag *alloc_frag = &rq->alloc_frag;
1090 char *buf;
1091 unsigned int xdp_headroom = virtnet_get_headroom(vi);
1092 void *ctx = (void *)(unsigned long)xdp_headroom;
1093 int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
1094 int err;
1095
1096 len = SKB_DATA_ALIGN(len) +
1097 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
1098 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
1099 return -ENOMEM;
1100
1101 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1102 get_page(alloc_frag->page);
1103 alloc_frag->offset += len;
1104 sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
1105 vi->hdr_len + GOOD_PACKET_LEN);
1106 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1107 if (err < 0)
1108 put_page(virt_to_head_page(buf));
1109 return err;
1110 }
1111
1112 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
1113 gfp_t gfp)
1114 {
1115 struct page *first, *list = NULL;
1116 char *p;
1117 int i, err, offset;
1118
1119 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
1120
1121 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
1122 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
1123 first = get_a_page(rq, gfp);
1124 if (!first) {
1125 if (list)
1126 give_pages(rq, list);
1127 return -ENOMEM;
1128 }
1129 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
1130
1131 /* chain new page in list head to match sg */
1132 first->private = (unsigned long)list;
1133 list = first;
1134 }
1135
1136 first = get_a_page(rq, gfp);
1137 if (!first) {
1138 give_pages(rq, list);
1139 return -ENOMEM;
1140 }
1141 p = page_address(first);
1142
1143 /* rq->sg[0], rq->sg[1] share the same page */
1144 /* a separated rq->sg[0] for header - required in case !any_header_sg */
1145 sg_set_buf(&rq->sg[0], p, vi->hdr_len);
1146
1147 /* rq->sg[1] for data packet, from offset */
1148 offset = sizeof(struct padded_vnet_hdr);
1149 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
1150
1151 /* chain first in list head */
1152 first->private = (unsigned long)list;
1153 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
1154 first, gfp);
1155 if (err < 0)
1156 give_pages(rq, first);
1157
1158 return err;
1159 }
1160
1161 static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
1162 struct ewma_pkt_len *avg_pkt_len,
1163 unsigned int room)
1164 {
1165 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
1166 unsigned int len;
1167
1168 if (room)
1169 return PAGE_SIZE - room;
1170
1171 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
1172 rq->min_buf_len, PAGE_SIZE - hdr_len);
1173
1174 return ALIGN(len, L1_CACHE_BYTES);
1175 }
1176
1177 static int add_recvbuf_mergeable(struct virtnet_info *vi,
1178 struct receive_queue *rq, gfp_t gfp)
1179 {
1180 struct page_frag *alloc_frag = &rq->alloc_frag;
1181 unsigned int headroom = virtnet_get_headroom(vi);
1182 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
1183 unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
1184 char *buf;
1185 void *ctx;
1186 int err;
1187 unsigned int len, hole;
1188
1189 /* Extra tailroom is needed to satisfy XDP's assumption. This
1190 * means rx frags coalescing won't work, but consider we've
1191 * disabled GSO for XDP, it won't be a big issue.
1192 */
1193 len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room);
1194 if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp)))
1195 return -ENOMEM;
1196
1197 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
1198 buf += headroom; /* advance address leaving hole at front of pkt */
1199 get_page(alloc_frag->page);
1200 alloc_frag->offset += len + room;
1201 hole = alloc_frag->size - alloc_frag->offset;
1202 if (hole < len + room) {
1203 /* To avoid internal fragmentation, if there is very likely not
1204 * enough space for another buffer, add the remaining space to
1205 * the current buffer.
1206 */
1207 len += hole;
1208 alloc_frag->offset += hole;
1209 }
1210
1211 sg_init_one(rq->sg, buf, len);
1212 ctx = mergeable_len_to_ctx(len, headroom);
1213 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
1214 if (err < 0)
1215 put_page(virt_to_head_page(buf));
1216
1217 return err;
1218 }
1219
1220 /*
1221 * Returns false if we couldn't fill entirely (OOM).
1222 *
1223 * Normally run in the receive path, but can also be run from ndo_open
1224 * before we're receiving packets, or from refill_work which is
1225 * careful to disable receiving (using napi_disable).
1226 */
1227 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
1228 gfp_t gfp)
1229 {
1230 int err;
1231 bool oom;
1232
1233 do {
1234 if (vi->mergeable_rx_bufs)
1235 err = add_recvbuf_mergeable(vi, rq, gfp);
1236 else if (vi->big_packets)
1237 err = add_recvbuf_big(vi, rq, gfp);
1238 else
1239 err = add_recvbuf_small(vi, rq, gfp);
1240
1241 oom = err == -ENOMEM;
1242 if (err)
1243 break;
1244 } while (rq->vq->num_free);
1245 if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
1246 unsigned long flags;
1247
1248 flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
1249 rq->stats.kicks++;
1250 u64_stats_update_end_irqrestore(&rq->stats.syncp, flags);
1251 }
1252
1253 return !oom;
1254 }
1255
1256 static void skb_recv_done(struct virtqueue *rvq)
1257 {
1258 struct virtnet_info *vi = rvq->vdev->priv;
1259 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
1260
1261 virtqueue_napi_schedule(&rq->napi, rvq);
1262 }
1263
1264 static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
1265 {
1266 napi_enable(napi);
1267
1268 /* If all buffers were filled by other side before we napi_enabled, we
1269 * won't get another interrupt, so process any outstanding packets now.
1270 * Call local_bh_enable after to trigger softIRQ processing.
1271 */
1272 local_bh_disable();
1273 virtqueue_napi_schedule(napi, vq);
1274 local_bh_enable();
1275 }
1276
1277 static void virtnet_napi_tx_enable(struct virtnet_info *vi,
1278 struct virtqueue *vq,
1279 struct napi_struct *napi)
1280 {
1281 if (!napi->weight)
1282 return;
1283
1284 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only
1285 * enable the feature if this is likely affine with the transmit path.
1286 */
1287 if (!vi->affinity_hint_set) {
1288 napi->weight = 0;
1289 return;
1290 }
1291
1292 return virtnet_napi_enable(vq, napi);
1293 }
1294
1295 static void virtnet_napi_tx_disable(struct napi_struct *napi)
1296 {
1297 if (napi->weight)
1298 napi_disable(napi);
1299 }
1300
1301 static void refill_work(struct work_struct *work)
1302 {
1303 struct virtnet_info *vi =
1304 container_of(work, struct virtnet_info, refill.work);
1305 bool still_empty;
1306 int i;
1307
1308 for (i = 0; i < vi->curr_queue_pairs; i++) {
1309 struct receive_queue *rq = &vi->rq[i];
1310
1311 napi_disable(&rq->napi);
1312 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
1313 virtnet_napi_enable(rq->vq, &rq->napi);
1314
1315 /* In theory, this can happen: if we don't get any buffers in
1316 * we will *never* try to fill again.
1317 */
1318 if (still_empty)
1319 schedule_delayed_work(&vi->refill, HZ/2);
1320 }
1321 }
1322
1323 static int virtnet_receive(struct receive_queue *rq, int budget,
1324 unsigned int *xdp_xmit)
1325 {
1326 struct virtnet_info *vi = rq->vq->vdev->priv;
1327 struct virtnet_rq_stats stats = {};
1328 unsigned int len;
1329 void *buf;
1330 int i;
1331
1332 if (!vi->big_packets || vi->mergeable_rx_bufs) {
1333 void *ctx;
1334
1335 while (stats.packets < budget &&
1336 (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) {
1337 receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats);
1338 stats.packets++;
1339 }
1340 } else {
1341 while (stats.packets < budget &&
1342 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
1343 receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats);
1344 stats.packets++;
1345 }
1346 }
1347
1348 if (rq->vq->num_free > min((unsigned int)budget, virtqueue_get_vring_size(rq->vq)) / 2) {
1349 if (!try_fill_recv(vi, rq, GFP_ATOMIC))
1350 schedule_delayed_work(&vi->refill, 0);
1351 }
1352
1353 u64_stats_update_begin(&rq->stats.syncp);
1354 for (i = 0; i < VIRTNET_RQ_STATS_LEN; i++) {
1355 size_t offset = virtnet_rq_stats_desc[i].offset;
1356 u64 *item;
1357
1358 item = (u64 *)((u8 *)&rq->stats + offset);
1359 *item += *(u64 *)((u8 *)&stats + offset);
1360 }
1361 u64_stats_update_end(&rq->stats.syncp);
1362
1363 return stats.packets;
1364 }
1365
1366 static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi)
1367 {
1368 unsigned int len;
1369 unsigned int packets = 0;
1370 unsigned int bytes = 0;
1371 void *ptr;
1372
1373 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
1374 if (likely(!is_xdp_frame(ptr))) {
1375 struct sk_buff *skb = ptr;
1376
1377 pr_debug("Sent skb %p\n", skb);
1378
1379 bytes += skb->len;
1380 napi_consume_skb(skb, in_napi);
1381 } else {
1382 struct xdp_frame *frame = ptr_to_xdp(ptr);
1383
1384 bytes += frame->len;
1385 xdp_return_frame(frame);
1386 }
1387 packets++;
1388 }
1389
1390 /* Avoid overhead when no packets have been processed
1391 * happens when called speculatively from start_xmit.
1392 */
1393 if (!packets)
1394 return;
1395
1396 u64_stats_update_begin(&sq->stats.syncp);
1397 sq->stats.bytes += bytes;
1398 sq->stats.packets += packets;
1399 u64_stats_update_end(&sq->stats.syncp);
1400 }
1401
1402 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
1403 {
1404 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
1405 return false;
1406 else if (q < vi->curr_queue_pairs)
1407 return true;
1408 else
1409 return false;
1410 }
1411
1412 static void virtnet_poll_cleantx(struct receive_queue *rq)
1413 {
1414 struct virtnet_info *vi = rq->vq->vdev->priv;
1415 unsigned int index = vq2rxq(rq->vq);
1416 struct send_queue *sq = &vi->sq[index];
1417 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
1418
1419 if (!sq->napi.weight || is_xdp_raw_buffer_queue(vi, index))
1420 return;
1421
1422 if (__netif_tx_trylock(txq)) {
1423 free_old_xmit_skbs(sq, true);
1424 __netif_tx_unlock(txq);
1425 }
1426
1427 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1428 netif_tx_wake_queue(txq);
1429 }
1430
1431 static int virtnet_poll(struct napi_struct *napi, int budget)
1432 {
1433 struct receive_queue *rq =
1434 container_of(napi, struct receive_queue, napi);
1435 struct virtnet_info *vi = rq->vq->vdev->priv;
1436 struct send_queue *sq;
1437 unsigned int received;
1438 unsigned int xdp_xmit = 0;
1439
1440 virtnet_poll_cleantx(rq);
1441
1442 received = virtnet_receive(rq, budget, &xdp_xmit);
1443
1444 /* Out of packets? */
1445 if (received < budget)
1446 virtqueue_napi_complete(napi, rq->vq, received);
1447
1448 if (xdp_xmit & VIRTIO_XDP_REDIR)
1449 xdp_do_flush();
1450
1451 if (xdp_xmit & VIRTIO_XDP_TX) {
1452 sq = virtnet_xdp_sq(vi);
1453 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1454 u64_stats_update_begin(&sq->stats.syncp);
1455 sq->stats.kicks++;
1456 u64_stats_update_end(&sq->stats.syncp);
1457 }
1458 }
1459
1460 return received;
1461 }
1462
1463 static int virtnet_open(struct net_device *dev)
1464 {
1465 struct virtnet_info *vi = netdev_priv(dev);
1466 int i, err;
1467
1468 for (i = 0; i < vi->max_queue_pairs; i++) {
1469 if (i < vi->curr_queue_pairs)
1470 /* Make sure we have some buffers: if oom use wq. */
1471 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
1472 schedule_delayed_work(&vi->refill, 0);
1473
1474 err = xdp_rxq_info_reg(&vi->rq[i].xdp_rxq, dev, i);
1475 if (err < 0)
1476 return err;
1477
1478 err = xdp_rxq_info_reg_mem_model(&vi->rq[i].xdp_rxq,
1479 MEM_TYPE_PAGE_SHARED, NULL);
1480 if (err < 0) {
1481 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
1482 return err;
1483 }
1484
1485 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
1486 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
1487 }
1488
1489 return 0;
1490 }
1491
1492 static int virtnet_poll_tx(struct napi_struct *napi, int budget)
1493 {
1494 struct send_queue *sq = container_of(napi, struct send_queue, napi);
1495 struct virtnet_info *vi = sq->vq->vdev->priv;
1496 unsigned int index = vq2txq(sq->vq);
1497 struct netdev_queue *txq;
1498
1499 if (unlikely(is_xdp_raw_buffer_queue(vi, index))) {
1500 /* We don't need to enable cb for XDP */
1501 napi_complete_done(napi, 0);
1502 return 0;
1503 }
1504
1505 txq = netdev_get_tx_queue(vi->dev, index);
1506 __netif_tx_lock(txq, raw_smp_processor_id());
1507 free_old_xmit_skbs(sq, true);
1508 __netif_tx_unlock(txq);
1509
1510 virtqueue_napi_complete(napi, sq->vq, 0);
1511
1512 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
1513 netif_tx_wake_queue(txq);
1514
1515 return 0;
1516 }
1517
1518 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
1519 {
1520 struct virtio_net_hdr_mrg_rxbuf *hdr;
1521 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
1522 struct virtnet_info *vi = sq->vq->vdev->priv;
1523 int num_sg;
1524 unsigned hdr_len = vi->hdr_len;
1525 bool can_push;
1526
1527 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
1528
1529 can_push = vi->any_header_sg &&
1530 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
1531 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
1532 /* Even if we can, don't push here yet as this would skew
1533 * csum_start offset below. */
1534 if (can_push)
1535 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
1536 else
1537 hdr = skb_vnet_hdr(skb);
1538
1539 if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
1540 virtio_is_little_endian(vi->vdev), false,
1541 0))
1542 BUG();
1543
1544 if (vi->mergeable_rx_bufs)
1545 hdr->num_buffers = 0;
1546
1547 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
1548 if (can_push) {
1549 __skb_push(skb, hdr_len);
1550 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
1551 if (unlikely(num_sg < 0))
1552 return num_sg;
1553 /* Pull header back to avoid skew in tx bytes calculations. */
1554 __skb_pull(skb, hdr_len);
1555 } else {
1556 sg_set_buf(sq->sg, hdr, hdr_len);
1557 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
1558 if (unlikely(num_sg < 0))
1559 return num_sg;
1560 num_sg++;
1561 }
1562 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
1563 }
1564
1565 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
1566 {
1567 struct virtnet_info *vi = netdev_priv(dev);
1568 int qnum = skb_get_queue_mapping(skb);
1569 struct send_queue *sq = &vi->sq[qnum];
1570 int err;
1571 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
1572 bool kick = !netdev_xmit_more();
1573 bool use_napi = sq->napi.weight;
1574
1575 /* Free up any pending old buffers before queueing new ones. */
1576 free_old_xmit_skbs(sq, false);
1577
1578 if (use_napi && kick)
1579 virtqueue_enable_cb_delayed(sq->vq);
1580
1581 /* timestamp packet in software */
1582 skb_tx_timestamp(skb);
1583
1584 /* Try to transmit */
1585 err = xmit_skb(sq, skb);
1586
1587 /* This should not happen! */
1588 if (unlikely(err)) {
1589 dev->stats.tx_fifo_errors++;
1590 if (net_ratelimit())
1591 dev_warn(&dev->dev,
1592 "Unexpected TXQ (%d) queue failure: %d\n",
1593 qnum, err);
1594 dev->stats.tx_dropped++;
1595 dev_kfree_skb_any(skb);
1596 return NETDEV_TX_OK;
1597 }
1598
1599 /* Don't wait up for transmitted skbs to be freed. */
1600 if (!use_napi) {
1601 skb_orphan(skb);
1602 nf_reset_ct(skb);
1603 }
1604
1605 /* If running out of space, stop queue to avoid getting packets that we
1606 * are then unable to transmit.
1607 * An alternative would be to force queuing layer to requeue the skb by
1608 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
1609 * returned in a normal path of operation: it means that driver is not
1610 * maintaining the TX queue stop/start state properly, and causes
1611 * the stack to do a non-trivial amount of useless work.
1612 * Since most packets only take 1 or 2 ring slots, stopping the queue
1613 * early means 16 slots are typically wasted.
1614 */
1615 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
1616 netif_stop_subqueue(dev, qnum);
1617 if (!use_napi &&
1618 unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
1619 /* More just got used, free them then recheck. */
1620 free_old_xmit_skbs(sq, false);
1621 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
1622 netif_start_subqueue(dev, qnum);
1623 virtqueue_disable_cb(sq->vq);
1624 }
1625 }
1626 }
1627
1628 if (kick || netif_xmit_stopped(txq)) {
1629 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
1630 u64_stats_update_begin(&sq->stats.syncp);
1631 sq->stats.kicks++;
1632 u64_stats_update_end(&sq->stats.syncp);
1633 }
1634 }
1635
1636 return NETDEV_TX_OK;
1637 }
1638
1639 /*
1640 * Send command via the control virtqueue and check status. Commands
1641 * supported by the hypervisor, as indicated by feature bits, should
1642 * never fail unless improperly formatted.
1643 */
1644 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
1645 struct scatterlist *out)
1646 {
1647 struct scatterlist *sgs[4], hdr, stat;
1648 unsigned out_num = 0, tmp;
1649
1650 /* Caller should know better */
1651 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
1652
1653 vi->ctrl->status = ~0;
1654 vi->ctrl->hdr.class = class;
1655 vi->ctrl->hdr.cmd = cmd;
1656 /* Add header */
1657 sg_init_one(&hdr, &vi->ctrl->hdr, sizeof(vi->ctrl->hdr));
1658 sgs[out_num++] = &hdr;
1659
1660 if (out)
1661 sgs[out_num++] = out;
1662
1663 /* Add return status. */
1664 sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status));
1665 sgs[out_num] = &stat;
1666
1667 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
1668 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
1669
1670 if (unlikely(!virtqueue_kick(vi->cvq)))
1671 return vi->ctrl->status == VIRTIO_NET_OK;
1672
1673 /* Spin for a response, the kick causes an ioport write, trapping
1674 * into the hypervisor, so the request should be handled immediately.
1675 */
1676 while (!virtqueue_get_buf(vi->cvq, &tmp) &&
1677 !virtqueue_is_broken(vi->cvq))
1678 cpu_relax();
1679
1680 return vi->ctrl->status == VIRTIO_NET_OK;
1681 }
1682
1683 static int virtnet_set_mac_address(struct net_device *dev, void *p)
1684 {
1685 struct virtnet_info *vi = netdev_priv(dev);
1686 struct virtio_device *vdev = vi->vdev;
1687 int ret;
1688 struct sockaddr *addr;
1689 struct scatterlist sg;
1690
1691 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
1692 return -EOPNOTSUPP;
1693
1694 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
1695 if (!addr)
1696 return -ENOMEM;
1697
1698 ret = eth_prepare_mac_addr_change(dev, addr);
1699 if (ret)
1700 goto out;
1701
1702 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
1703 sg_init_one(&sg, addr->sa_data, dev->addr_len);
1704 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1705 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
1706 dev_warn(&vdev->dev,
1707 "Failed to set mac address by vq command.\n");
1708 ret = -EINVAL;
1709 goto out;
1710 }
1711 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
1712 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
1713 unsigned int i;
1714
1715 /* Naturally, this has an atomicity problem. */
1716 for (i = 0; i < dev->addr_len; i++)
1717 virtio_cwrite8(vdev,
1718 offsetof(struct virtio_net_config, mac) +
1719 i, addr->sa_data[i]);
1720 }
1721
1722 eth_commit_mac_addr_change(dev, p);
1723 ret = 0;
1724
1725 out:
1726 kfree(addr);
1727 return ret;
1728 }
1729
1730 static void virtnet_stats(struct net_device *dev,
1731 struct rtnl_link_stats64 *tot)
1732 {
1733 struct virtnet_info *vi = netdev_priv(dev);
1734 unsigned int start;
1735 int i;
1736
1737 for (i = 0; i < vi->max_queue_pairs; i++) {
1738 u64 tpackets, tbytes, rpackets, rbytes, rdrops;
1739 struct receive_queue *rq = &vi->rq[i];
1740 struct send_queue *sq = &vi->sq[i];
1741
1742 do {
1743 start = u64_stats_fetch_begin_irq(&sq->stats.syncp);
1744 tpackets = sq->stats.packets;
1745 tbytes = sq->stats.bytes;
1746 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start));
1747
1748 do {
1749 start = u64_stats_fetch_begin_irq(&rq->stats.syncp);
1750 rpackets = rq->stats.packets;
1751 rbytes = rq->stats.bytes;
1752 rdrops = rq->stats.drops;
1753 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start));
1754
1755 tot->rx_packets += rpackets;
1756 tot->tx_packets += tpackets;
1757 tot->rx_bytes += rbytes;
1758 tot->tx_bytes += tbytes;
1759 tot->rx_dropped += rdrops;
1760 }
1761
1762 tot->tx_dropped = dev->stats.tx_dropped;
1763 tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
1764 tot->rx_length_errors = dev->stats.rx_length_errors;
1765 tot->rx_frame_errors = dev->stats.rx_frame_errors;
1766 }
1767
1768 static void virtnet_ack_link_announce(struct virtnet_info *vi)
1769 {
1770 rtnl_lock();
1771 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
1772 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
1773 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
1774 rtnl_unlock();
1775 }
1776
1777 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1778 {
1779 struct scatterlist sg;
1780 struct net_device *dev = vi->dev;
1781
1782 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
1783 return 0;
1784
1785 vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
1786 sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq));
1787
1788 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
1789 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
1790 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
1791 queue_pairs);
1792 return -EINVAL;
1793 } else {
1794 vi->curr_queue_pairs = queue_pairs;
1795 /* virtnet_open() will refill when device is going to up. */
1796 if (dev->flags & IFF_UP)
1797 schedule_delayed_work(&vi->refill, 0);
1798 }
1799
1800 return 0;
1801 }
1802
1803 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
1804 {
1805 int err;
1806
1807 rtnl_lock();
1808 err = _virtnet_set_queues(vi, queue_pairs);
1809 rtnl_unlock();
1810 return err;
1811 }
1812
1813 static int virtnet_close(struct net_device *dev)
1814 {
1815 struct virtnet_info *vi = netdev_priv(dev);
1816 int i;
1817
1818 /* Make sure refill_work doesn't re-enable napi! */
1819 cancel_delayed_work_sync(&vi->refill);
1820
1821 for (i = 0; i < vi->max_queue_pairs; i++) {
1822 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
1823 napi_disable(&vi->rq[i].napi);
1824 virtnet_napi_tx_disable(&vi->sq[i].napi);
1825 }
1826
1827 return 0;
1828 }
1829
1830 static void virtnet_set_rx_mode(struct net_device *dev)
1831 {
1832 struct virtnet_info *vi = netdev_priv(dev);
1833 struct scatterlist sg[2];
1834 struct virtio_net_ctrl_mac *mac_data;
1835 struct netdev_hw_addr *ha;
1836 int uc_count;
1837 int mc_count;
1838 void *buf;
1839 int i;
1840
1841 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */
1842 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
1843 return;
1844
1845 vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0);
1846 vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
1847
1848 sg_init_one(sg, &vi->ctrl->promisc, sizeof(vi->ctrl->promisc));
1849
1850 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1851 VIRTIO_NET_CTRL_RX_PROMISC, sg))
1852 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
1853 vi->ctrl->promisc ? "en" : "dis");
1854
1855 sg_init_one(sg, &vi->ctrl->allmulti, sizeof(vi->ctrl->allmulti));
1856
1857 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
1858 VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
1859 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
1860 vi->ctrl->allmulti ? "en" : "dis");
1861
1862 uc_count = netdev_uc_count(dev);
1863 mc_count = netdev_mc_count(dev);
1864 /* MAC filter - use one buffer for both lists */
1865 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
1866 (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
1867 mac_data = buf;
1868 if (!buf)
1869 return;
1870
1871 sg_init_table(sg, 2);
1872
1873 /* Store the unicast list and count in the front of the buffer */
1874 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
1875 i = 0;
1876 netdev_for_each_uc_addr(ha, dev)
1877 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1878
1879 sg_set_buf(&sg[0], mac_data,
1880 sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
1881
1882 /* multicast list and count fill the end */
1883 mac_data = (void *)&mac_data->macs[uc_count][0];
1884
1885 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
1886 i = 0;
1887 netdev_for_each_mc_addr(ha, dev)
1888 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
1889
1890 sg_set_buf(&sg[1], mac_data,
1891 sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
1892
1893 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
1894 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
1895 dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
1896
1897 kfree(buf);
1898 }
1899
1900 static int virtnet_vlan_rx_add_vid(struct net_device *dev,
1901 __be16 proto, u16 vid)
1902 {
1903 struct virtnet_info *vi = netdev_priv(dev);
1904 struct scatterlist sg;
1905
1906 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
1907 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
1908
1909 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1910 VIRTIO_NET_CTRL_VLAN_ADD, &sg))
1911 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
1912 return 0;
1913 }
1914
1915 static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
1916 __be16 proto, u16 vid)
1917 {
1918 struct virtnet_info *vi = netdev_priv(dev);
1919 struct scatterlist sg;
1920
1921 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
1922 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
1923
1924 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
1925 VIRTIO_NET_CTRL_VLAN_DEL, &sg))
1926 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
1927 return 0;
1928 }
1929
1930 static void virtnet_clean_affinity(struct virtnet_info *vi)
1931 {
1932 int i;
1933
1934 if (vi->affinity_hint_set) {
1935 for (i = 0; i < vi->max_queue_pairs; i++) {
1936 virtqueue_set_affinity(vi->rq[i].vq, NULL);
1937 virtqueue_set_affinity(vi->sq[i].vq, NULL);
1938 }
1939
1940 vi->affinity_hint_set = false;
1941 }
1942 }
1943
1944 static void virtnet_set_affinity(struct virtnet_info *vi)
1945 {
1946 cpumask_var_t mask;
1947 int stragglers;
1948 int group_size;
1949 int i, j, cpu;
1950 int num_cpu;
1951 int stride;
1952
1953 if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
1954 virtnet_clean_affinity(vi);
1955 return;
1956 }
1957
1958 num_cpu = num_online_cpus();
1959 stride = max_t(int, num_cpu / vi->curr_queue_pairs, 1);
1960 stragglers = num_cpu >= vi->curr_queue_pairs ?
1961 num_cpu % vi->curr_queue_pairs :
1962 0;
1963 cpu = cpumask_next(-1, cpu_online_mask);
1964
1965 for (i = 0; i < vi->curr_queue_pairs; i++) {
1966 group_size = stride + (i < stragglers ? 1 : 0);
1967
1968 for (j = 0; j < group_size; j++) {
1969 cpumask_set_cpu(cpu, mask);
1970 cpu = cpumask_next_wrap(cpu, cpu_online_mask,
1971 nr_cpu_ids, false);
1972 }
1973 virtqueue_set_affinity(vi->rq[i].vq, mask);
1974 virtqueue_set_affinity(vi->sq[i].vq, mask);
1975 __netif_set_xps_queue(vi->dev, cpumask_bits(mask), i, false);
1976 cpumask_clear(mask);
1977 }
1978
1979 vi->affinity_hint_set = true;
1980 free_cpumask_var(mask);
1981 }
1982
1983 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
1984 {
1985 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1986 node);
1987 virtnet_set_affinity(vi);
1988 return 0;
1989 }
1990
1991 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
1992 {
1993 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
1994 node_dead);
1995 virtnet_set_affinity(vi);
1996 return 0;
1997 }
1998
1999 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
2000 {
2001 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
2002 node);
2003
2004 virtnet_clean_affinity(vi);
2005 return 0;
2006 }
2007
2008 static enum cpuhp_state virtionet_online;
2009
2010 static int virtnet_cpu_notif_add(struct virtnet_info *vi)
2011 {
2012 int ret;
2013
2014 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
2015 if (ret)
2016 return ret;
2017 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2018 &vi->node_dead);
2019 if (!ret)
2020 return ret;
2021 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2022 return ret;
2023 }
2024
2025 static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
2026 {
2027 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
2028 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
2029 &vi->node_dead);
2030 }
2031
2032 static void virtnet_get_ringparam(struct net_device *dev,
2033 struct ethtool_ringparam *ring)
2034 {
2035 struct virtnet_info *vi = netdev_priv(dev);
2036
2037 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
2038 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
2039 ring->rx_pending = ring->rx_max_pending;
2040 ring->tx_pending = ring->tx_max_pending;
2041 }
2042
2043
2044 static void virtnet_get_drvinfo(struct net_device *dev,
2045 struct ethtool_drvinfo *info)
2046 {
2047 struct virtnet_info *vi = netdev_priv(dev);
2048 struct virtio_device *vdev = vi->vdev;
2049
2050 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
2051 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
2052 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
2053
2054 }
2055
2056 /* TODO: Eliminate OOO packets during switching */
2057 static int virtnet_set_channels(struct net_device *dev,
2058 struct ethtool_channels *channels)
2059 {
2060 struct virtnet_info *vi = netdev_priv(dev);
2061 u16 queue_pairs = channels->combined_count;
2062 int err;
2063
2064 /* We don't support separate rx/tx channels.
2065 * We don't allow setting 'other' channels.
2066 */
2067 if (channels->rx_count || channels->tx_count || channels->other_count)
2068 return -EINVAL;
2069
2070 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
2071 return -EINVAL;
2072
2073 /* For now we don't support modifying channels while XDP is loaded
2074 * also when XDP is loaded all RX queues have XDP programs so we only
2075 * need to check a single RX queue.
2076 */
2077 if (vi->rq[0].xdp_prog)
2078 return -EINVAL;
2079
2080 get_online_cpus();
2081 err = _virtnet_set_queues(vi, queue_pairs);
2082 if (!err) {
2083 netif_set_real_num_tx_queues(dev, queue_pairs);
2084 netif_set_real_num_rx_queues(dev, queue_pairs);
2085
2086 virtnet_set_affinity(vi);
2087 }
2088 put_online_cpus();
2089
2090 return err;
2091 }
2092
2093 static void virtnet_get_strings(struct net_device *dev, u32 stringset, u8 *data)
2094 {
2095 struct virtnet_info *vi = netdev_priv(dev);
2096 char *p = (char *)data;
2097 unsigned int i, j;
2098
2099 switch (stringset) {
2100 case ETH_SS_STATS:
2101 for (i = 0; i < vi->curr_queue_pairs; i++) {
2102 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2103 snprintf(p, ETH_GSTRING_LEN, "rx_queue_%u_%s",
2104 i, virtnet_rq_stats_desc[j].desc);
2105 p += ETH_GSTRING_LEN;
2106 }
2107 }
2108
2109 for (i = 0; i < vi->curr_queue_pairs; i++) {
2110 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2111 snprintf(p, ETH_GSTRING_LEN, "tx_queue_%u_%s",
2112 i, virtnet_sq_stats_desc[j].desc);
2113 p += ETH_GSTRING_LEN;
2114 }
2115 }
2116 break;
2117 }
2118 }
2119
2120 static int virtnet_get_sset_count(struct net_device *dev, int sset)
2121 {
2122 struct virtnet_info *vi = netdev_priv(dev);
2123
2124 switch (sset) {
2125 case ETH_SS_STATS:
2126 return vi->curr_queue_pairs * (VIRTNET_RQ_STATS_LEN +
2127 VIRTNET_SQ_STATS_LEN);
2128 default:
2129 return -EOPNOTSUPP;
2130 }
2131 }
2132
2133 static void virtnet_get_ethtool_stats(struct net_device *dev,
2134 struct ethtool_stats *stats, u64 *data)
2135 {
2136 struct virtnet_info *vi = netdev_priv(dev);
2137 unsigned int idx = 0, start, i, j;
2138 const u8 *stats_base;
2139 size_t offset;
2140
2141 for (i = 0; i < vi->curr_queue_pairs; i++) {
2142 struct receive_queue *rq = &vi->rq[i];
2143
2144 stats_base = (u8 *)&rq->stats;
2145 do {
2146 start = u64_stats_fetch_begin_irq(&rq->stats.syncp);
2147 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
2148 offset = virtnet_rq_stats_desc[j].offset;
2149 data[idx + j] = *(u64 *)(stats_base + offset);
2150 }
2151 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start));
2152 idx += VIRTNET_RQ_STATS_LEN;
2153 }
2154
2155 for (i = 0; i < vi->curr_queue_pairs; i++) {
2156 struct send_queue *sq = &vi->sq[i];
2157
2158 stats_base = (u8 *)&sq->stats;
2159 do {
2160 start = u64_stats_fetch_begin_irq(&sq->stats.syncp);
2161 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
2162 offset = virtnet_sq_stats_desc[j].offset;
2163 data[idx + j] = *(u64 *)(stats_base + offset);
2164 }
2165 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start));
2166 idx += VIRTNET_SQ_STATS_LEN;
2167 }
2168 }
2169
2170 static void virtnet_get_channels(struct net_device *dev,
2171 struct ethtool_channels *channels)
2172 {
2173 struct virtnet_info *vi = netdev_priv(dev);
2174
2175 channels->combined_count = vi->curr_queue_pairs;
2176 channels->max_combined = vi->max_queue_pairs;
2177 channels->max_other = 0;
2178 channels->rx_count = 0;
2179 channels->tx_count = 0;
2180 channels->other_count = 0;
2181 }
2182
2183 static int virtnet_set_link_ksettings(struct net_device *dev,
2184 const struct ethtool_link_ksettings *cmd)
2185 {
2186 struct virtnet_info *vi = netdev_priv(dev);
2187
2188 return ethtool_virtdev_set_link_ksettings(dev, cmd,
2189 &vi->speed, &vi->duplex);
2190 }
2191
2192 static int virtnet_get_link_ksettings(struct net_device *dev,
2193 struct ethtool_link_ksettings *cmd)
2194 {
2195 struct virtnet_info *vi = netdev_priv(dev);
2196
2197 cmd->base.speed = vi->speed;
2198 cmd->base.duplex = vi->duplex;
2199 cmd->base.port = PORT_OTHER;
2200
2201 return 0;
2202 }
2203
2204 static int virtnet_set_coalesce(struct net_device *dev,
2205 struct ethtool_coalesce *ec)
2206 {
2207 struct virtnet_info *vi = netdev_priv(dev);
2208 int i, napi_weight;
2209
2210 if (ec->tx_max_coalesced_frames > 1 ||
2211 ec->rx_max_coalesced_frames != 1)
2212 return -EINVAL;
2213
2214 napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
2215 if (napi_weight ^ vi->sq[0].napi.weight) {
2216 if (dev->flags & IFF_UP)
2217 return -EBUSY;
2218 for (i = 0; i < vi->max_queue_pairs; i++)
2219 vi->sq[i].napi.weight = napi_weight;
2220 }
2221
2222 return 0;
2223 }
2224
2225 static int virtnet_get_coalesce(struct net_device *dev,
2226 struct ethtool_coalesce *ec)
2227 {
2228 struct ethtool_coalesce ec_default = {
2229 .cmd = ETHTOOL_GCOALESCE,
2230 .rx_max_coalesced_frames = 1,
2231 };
2232 struct virtnet_info *vi = netdev_priv(dev);
2233
2234 memcpy(ec, &ec_default, sizeof(ec_default));
2235
2236 if (vi->sq[0].napi.weight)
2237 ec->tx_max_coalesced_frames = 1;
2238
2239 return 0;
2240 }
2241
2242 static void virtnet_init_settings(struct net_device *dev)
2243 {
2244 struct virtnet_info *vi = netdev_priv(dev);
2245
2246 vi->speed = SPEED_UNKNOWN;
2247 vi->duplex = DUPLEX_UNKNOWN;
2248 }
2249
2250 static void virtnet_update_settings(struct virtnet_info *vi)
2251 {
2252 u32 speed;
2253 u8 duplex;
2254
2255 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
2256 return;
2257
2258 speed = virtio_cread32(vi->vdev, offsetof(struct virtio_net_config,
2259 speed));
2260 if (ethtool_validate_speed(speed))
2261 vi->speed = speed;
2262 duplex = virtio_cread8(vi->vdev, offsetof(struct virtio_net_config,
2263 duplex));
2264 if (ethtool_validate_duplex(duplex))
2265 vi->duplex = duplex;
2266 }
2267
2268 static const struct ethtool_ops virtnet_ethtool_ops = {
2269 .supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES,
2270 .get_drvinfo = virtnet_get_drvinfo,
2271 .get_link = ethtool_op_get_link,
2272 .get_ringparam = virtnet_get_ringparam,
2273 .get_strings = virtnet_get_strings,
2274 .get_sset_count = virtnet_get_sset_count,
2275 .get_ethtool_stats = virtnet_get_ethtool_stats,
2276 .set_channels = virtnet_set_channels,
2277 .get_channels = virtnet_get_channels,
2278 .get_ts_info = ethtool_op_get_ts_info,
2279 .get_link_ksettings = virtnet_get_link_ksettings,
2280 .set_link_ksettings = virtnet_set_link_ksettings,
2281 .set_coalesce = virtnet_set_coalesce,
2282 .get_coalesce = virtnet_get_coalesce,
2283 };
2284
2285 static void virtnet_freeze_down(struct virtio_device *vdev)
2286 {
2287 struct virtnet_info *vi = vdev->priv;
2288 int i;
2289
2290 /* Make sure no work handler is accessing the device */
2291 flush_work(&vi->config_work);
2292
2293 netif_tx_lock_bh(vi->dev);
2294 netif_device_detach(vi->dev);
2295 netif_tx_unlock_bh(vi->dev);
2296 cancel_delayed_work_sync(&vi->refill);
2297
2298 if (netif_running(vi->dev)) {
2299 for (i = 0; i < vi->max_queue_pairs; i++) {
2300 napi_disable(&vi->rq[i].napi);
2301 virtnet_napi_tx_disable(&vi->sq[i].napi);
2302 }
2303 }
2304 }
2305
2306 static int init_vqs(struct virtnet_info *vi);
2307
2308 static int virtnet_restore_up(struct virtio_device *vdev)
2309 {
2310 struct virtnet_info *vi = vdev->priv;
2311 int err, i;
2312
2313 err = init_vqs(vi);
2314 if (err)
2315 return err;
2316
2317 virtio_device_ready(vdev);
2318
2319 if (netif_running(vi->dev)) {
2320 for (i = 0; i < vi->curr_queue_pairs; i++)
2321 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
2322 schedule_delayed_work(&vi->refill, 0);
2323
2324 for (i = 0; i < vi->max_queue_pairs; i++) {
2325 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2326 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
2327 &vi->sq[i].napi);
2328 }
2329 }
2330
2331 netif_tx_lock_bh(vi->dev);
2332 netif_device_attach(vi->dev);
2333 netif_tx_unlock_bh(vi->dev);
2334 return err;
2335 }
2336
2337 static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
2338 {
2339 struct scatterlist sg;
2340 vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads);
2341
2342 sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads));
2343
2344 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
2345 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
2346 dev_warn(&vi->dev->dev, "Fail to set guest offload.\n");
2347 return -EINVAL;
2348 }
2349
2350 return 0;
2351 }
2352
2353 static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
2354 {
2355 u64 offloads = 0;
2356
2357 if (!vi->guest_offloads)
2358 return 0;
2359
2360 return virtnet_set_guest_offloads(vi, offloads);
2361 }
2362
2363 static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
2364 {
2365 u64 offloads = vi->guest_offloads;
2366
2367 if (!vi->guest_offloads)
2368 return 0;
2369
2370 return virtnet_set_guest_offloads(vi, offloads);
2371 }
2372
2373 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
2374 struct netlink_ext_ack *extack)
2375 {
2376 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
2377 struct virtnet_info *vi = netdev_priv(dev);
2378 struct bpf_prog *old_prog;
2379 u16 xdp_qp = 0, curr_qp;
2380 int i, err;
2381
2382 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
2383 && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
2384 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
2385 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
2386 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
2387 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))) {
2388 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO/CSUM, disable LRO/CSUM first");
2389 return -EOPNOTSUPP;
2390 }
2391
2392 if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
2393 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
2394 return -EINVAL;
2395 }
2396
2397 if (dev->mtu > max_sz) {
2398 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
2399 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
2400 return -EINVAL;
2401 }
2402
2403 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
2404 if (prog)
2405 xdp_qp = nr_cpu_ids;
2406
2407 /* XDP requires extra queues for XDP_TX */
2408 if (curr_qp + xdp_qp > vi->max_queue_pairs) {
2409 NL_SET_ERR_MSG_MOD(extack, "Too few free TX rings available");
2410 netdev_warn(dev, "request %i queues but max is %i\n",
2411 curr_qp + xdp_qp, vi->max_queue_pairs);
2412 return -ENOMEM;
2413 }
2414
2415 old_prog = rtnl_dereference(vi->rq[0].xdp_prog);
2416 if (!prog && !old_prog)
2417 return 0;
2418
2419 if (prog)
2420 bpf_prog_add(prog, vi->max_queue_pairs - 1);
2421
2422 /* Make sure NAPI is not using any XDP TX queues for RX. */
2423 if (netif_running(dev)) {
2424 for (i = 0; i < vi->max_queue_pairs; i++) {
2425 napi_disable(&vi->rq[i].napi);
2426 virtnet_napi_tx_disable(&vi->sq[i].napi);
2427 }
2428 }
2429
2430 if (!prog) {
2431 for (i = 0; i < vi->max_queue_pairs; i++) {
2432 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
2433 if (i == 0)
2434 virtnet_restore_guest_offloads(vi);
2435 }
2436 synchronize_net();
2437 }
2438
2439 err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
2440 if (err)
2441 goto err;
2442 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
2443 vi->xdp_queue_pairs = xdp_qp;
2444
2445 if (prog) {
2446 for (i = 0; i < vi->max_queue_pairs; i++) {
2447 rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
2448 if (i == 0 && !old_prog)
2449 virtnet_clear_guest_offloads(vi);
2450 }
2451 }
2452
2453 for (i = 0; i < vi->max_queue_pairs; i++) {
2454 if (old_prog)
2455 bpf_prog_put(old_prog);
2456 if (netif_running(dev)) {
2457 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2458 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
2459 &vi->sq[i].napi);
2460 }
2461 }
2462
2463 return 0;
2464
2465 err:
2466 if (!prog) {
2467 virtnet_clear_guest_offloads(vi);
2468 for (i = 0; i < vi->max_queue_pairs; i++)
2469 rcu_assign_pointer(vi->rq[i].xdp_prog, old_prog);
2470 }
2471
2472 if (netif_running(dev)) {
2473 for (i = 0; i < vi->max_queue_pairs; i++) {
2474 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
2475 virtnet_napi_tx_enable(vi, vi->sq[i].vq,
2476 &vi->sq[i].napi);
2477 }
2478 }
2479 if (prog)
2480 bpf_prog_sub(prog, vi->max_queue_pairs - 1);
2481 return err;
2482 }
2483
2484 static u32 virtnet_xdp_query(struct net_device *dev)
2485 {
2486 struct virtnet_info *vi = netdev_priv(dev);
2487 const struct bpf_prog *xdp_prog;
2488 int i;
2489
2490 for (i = 0; i < vi->max_queue_pairs; i++) {
2491 xdp_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2492 if (xdp_prog)
2493 return xdp_prog->aux->id;
2494 }
2495 return 0;
2496 }
2497
2498 static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
2499 {
2500 switch (xdp->command) {
2501 case XDP_SETUP_PROG:
2502 return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
2503 case XDP_QUERY_PROG:
2504 xdp->prog_id = virtnet_xdp_query(dev);
2505 return 0;
2506 default:
2507 return -EINVAL;
2508 }
2509 }
2510
2511 static int virtnet_get_phys_port_name(struct net_device *dev, char *buf,
2512 size_t len)
2513 {
2514 struct virtnet_info *vi = netdev_priv(dev);
2515 int ret;
2516
2517 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
2518 return -EOPNOTSUPP;
2519
2520 ret = snprintf(buf, len, "sby");
2521 if (ret >= len)
2522 return -EOPNOTSUPP;
2523
2524 return 0;
2525 }
2526
2527 static int virtnet_set_features(struct net_device *dev,
2528 netdev_features_t features)
2529 {
2530 struct virtnet_info *vi = netdev_priv(dev);
2531 u64 offloads;
2532 int err;
2533
2534 if ((dev->features ^ features) & NETIF_F_LRO) {
2535 if (vi->xdp_queue_pairs)
2536 return -EBUSY;
2537
2538 if (features & NETIF_F_LRO)
2539 offloads = vi->guest_offloads_capable;
2540 else
2541 offloads = 0;
2542
2543 err = virtnet_set_guest_offloads(vi, offloads);
2544 if (err)
2545 return err;
2546 vi->guest_offloads = offloads;
2547 }
2548
2549 return 0;
2550 }
2551
2552 static const struct net_device_ops virtnet_netdev = {
2553 .ndo_open = virtnet_open,
2554 .ndo_stop = virtnet_close,
2555 .ndo_start_xmit = start_xmit,
2556 .ndo_validate_addr = eth_validate_addr,
2557 .ndo_set_mac_address = virtnet_set_mac_address,
2558 .ndo_set_rx_mode = virtnet_set_rx_mode,
2559 .ndo_get_stats64 = virtnet_stats,
2560 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
2561 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
2562 .ndo_bpf = virtnet_xdp,
2563 .ndo_xdp_xmit = virtnet_xdp_xmit,
2564 .ndo_features_check = passthru_features_check,
2565 .ndo_get_phys_port_name = virtnet_get_phys_port_name,
2566 .ndo_set_features = virtnet_set_features,
2567 };
2568
2569 static void virtnet_config_changed_work(struct work_struct *work)
2570 {
2571 struct virtnet_info *vi =
2572 container_of(work, struct virtnet_info, config_work);
2573 u16 v;
2574
2575 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
2576 struct virtio_net_config, status, &v) < 0)
2577 return;
2578
2579 if (v & VIRTIO_NET_S_ANNOUNCE) {
2580 netdev_notify_peers(vi->dev);
2581 virtnet_ack_link_announce(vi);
2582 }
2583
2584 /* Ignore unknown (future) status bits */
2585 v &= VIRTIO_NET_S_LINK_UP;
2586
2587 if (vi->status == v)
2588 return;
2589
2590 vi->status = v;
2591
2592 if (vi->status & VIRTIO_NET_S_LINK_UP) {
2593 virtnet_update_settings(vi);
2594 netif_carrier_on(vi->dev);
2595 netif_tx_wake_all_queues(vi->dev);
2596 } else {
2597 netif_carrier_off(vi->dev);
2598 netif_tx_stop_all_queues(vi->dev);
2599 }
2600 }
2601
2602 static void virtnet_config_changed(struct virtio_device *vdev)
2603 {
2604 struct virtnet_info *vi = vdev->priv;
2605
2606 schedule_work(&vi->config_work);
2607 }
2608
2609 static void virtnet_free_queues(struct virtnet_info *vi)
2610 {
2611 int i;
2612
2613 for (i = 0; i < vi->max_queue_pairs; i++) {
2614 napi_hash_del(&vi->rq[i].napi);
2615 netif_napi_del(&vi->rq[i].napi);
2616 netif_napi_del(&vi->sq[i].napi);
2617 }
2618
2619 /* We called napi_hash_del() before netif_napi_del(),
2620 * we need to respect an RCU grace period before freeing vi->rq
2621 */
2622 synchronize_net();
2623
2624 kfree(vi->rq);
2625 kfree(vi->sq);
2626 kfree(vi->ctrl);
2627 }
2628
2629 static void _free_receive_bufs(struct virtnet_info *vi)
2630 {
2631 struct bpf_prog *old_prog;
2632 int i;
2633
2634 for (i = 0; i < vi->max_queue_pairs; i++) {
2635 while (vi->rq[i].pages)
2636 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
2637
2638 old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
2639 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
2640 if (old_prog)
2641 bpf_prog_put(old_prog);
2642 }
2643 }
2644
2645 static void free_receive_bufs(struct virtnet_info *vi)
2646 {
2647 rtnl_lock();
2648 _free_receive_bufs(vi);
2649 rtnl_unlock();
2650 }
2651
2652 static void free_receive_page_frags(struct virtnet_info *vi)
2653 {
2654 int i;
2655 for (i = 0; i < vi->max_queue_pairs; i++)
2656 if (vi->rq[i].alloc_frag.page)
2657 put_page(vi->rq[i].alloc_frag.page);
2658 }
2659
2660 static void free_unused_bufs(struct virtnet_info *vi)
2661 {
2662 void *buf;
2663 int i;
2664
2665 for (i = 0; i < vi->max_queue_pairs; i++) {
2666 struct virtqueue *vq = vi->sq[i].vq;
2667 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2668 if (!is_xdp_frame(buf))
2669 dev_kfree_skb(buf);
2670 else
2671 xdp_return_frame(ptr_to_xdp(buf));
2672 }
2673 }
2674
2675 for (i = 0; i < vi->max_queue_pairs; i++) {
2676 struct virtqueue *vq = vi->rq[i].vq;
2677
2678 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
2679 if (vi->mergeable_rx_bufs) {
2680 put_page(virt_to_head_page(buf));
2681 } else if (vi->big_packets) {
2682 give_pages(&vi->rq[i], buf);
2683 } else {
2684 put_page(virt_to_head_page(buf));
2685 }
2686 }
2687 }
2688 }
2689
2690 static void virtnet_del_vqs(struct virtnet_info *vi)
2691 {
2692 struct virtio_device *vdev = vi->vdev;
2693
2694 virtnet_clean_affinity(vi);
2695
2696 vdev->config->del_vqs(vdev);
2697
2698 virtnet_free_queues(vi);
2699 }
2700
2701 /* How large should a single buffer be so a queue full of these can fit at
2702 * least one full packet?
2703 * Logic below assumes the mergeable buffer header is used.
2704 */
2705 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
2706 {
2707 const unsigned int hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
2708 unsigned int rq_size = virtqueue_get_vring_size(vq);
2709 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
2710 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
2711 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
2712
2713 return max(max(min_buf_len, hdr_len) - hdr_len,
2714 (unsigned int)GOOD_PACKET_LEN);
2715 }
2716
2717 static int virtnet_find_vqs(struct virtnet_info *vi)
2718 {
2719 vq_callback_t **callbacks;
2720 struct virtqueue **vqs;
2721 int ret = -ENOMEM;
2722 int i, total_vqs;
2723 const char **names;
2724 bool *ctx;
2725
2726 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
2727 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
2728 * possible control vq.
2729 */
2730 total_vqs = vi->max_queue_pairs * 2 +
2731 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
2732
2733 /* Allocate space for find_vqs parameters */
2734 vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
2735 if (!vqs)
2736 goto err_vq;
2737 callbacks = kmalloc_array(total_vqs, sizeof(*callbacks), GFP_KERNEL);
2738 if (!callbacks)
2739 goto err_callback;
2740 names = kmalloc_array(total_vqs, sizeof(*names), GFP_KERNEL);
2741 if (!names)
2742 goto err_names;
2743 if (!vi->big_packets || vi->mergeable_rx_bufs) {
2744 ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL);
2745 if (!ctx)
2746 goto err_ctx;
2747 } else {
2748 ctx = NULL;
2749 }
2750
2751 /* Parameters for control virtqueue, if any */
2752 if (vi->has_cvq) {
2753 callbacks[total_vqs - 1] = NULL;
2754 names[total_vqs - 1] = "control";
2755 }
2756
2757 /* Allocate/initialize parameters for send/receive virtqueues */
2758 for (i = 0; i < vi->max_queue_pairs; i++) {
2759 callbacks[rxq2vq(i)] = skb_recv_done;
2760 callbacks[txq2vq(i)] = skb_xmit_done;
2761 sprintf(vi->rq[i].name, "input.%d", i);
2762 sprintf(vi->sq[i].name, "output.%d", i);
2763 names[rxq2vq(i)] = vi->rq[i].name;
2764 names[txq2vq(i)] = vi->sq[i].name;
2765 if (ctx)
2766 ctx[rxq2vq(i)] = true;
2767 }
2768
2769 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
2770 names, ctx, NULL);
2771 if (ret)
2772 goto err_find;
2773
2774 if (vi->has_cvq) {
2775 vi->cvq = vqs[total_vqs - 1];
2776 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
2777 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2778 }
2779
2780 for (i = 0; i < vi->max_queue_pairs; i++) {
2781 vi->rq[i].vq = vqs[rxq2vq(i)];
2782 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
2783 vi->sq[i].vq = vqs[txq2vq(i)];
2784 }
2785
2786 /* run here: ret == 0. */
2787
2788
2789 err_find:
2790 kfree(ctx);
2791 err_ctx:
2792 kfree(names);
2793 err_names:
2794 kfree(callbacks);
2795 err_callback:
2796 kfree(vqs);
2797 err_vq:
2798 return ret;
2799 }
2800
2801 static int virtnet_alloc_queues(struct virtnet_info *vi)
2802 {
2803 int i;
2804
2805 vi->ctrl = kzalloc(sizeof(*vi->ctrl), GFP_KERNEL);
2806 if (!vi->ctrl)
2807 goto err_ctrl;
2808 vi->sq = kcalloc(vi->max_queue_pairs, sizeof(*vi->sq), GFP_KERNEL);
2809 if (!vi->sq)
2810 goto err_sq;
2811 vi->rq = kcalloc(vi->max_queue_pairs, sizeof(*vi->rq), GFP_KERNEL);
2812 if (!vi->rq)
2813 goto err_rq;
2814
2815 INIT_DELAYED_WORK(&vi->refill, refill_work);
2816 for (i = 0; i < vi->max_queue_pairs; i++) {
2817 vi->rq[i].pages = NULL;
2818 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
2819 napi_weight);
2820 netif_tx_napi_add(vi->dev, &vi->sq[i].napi, virtnet_poll_tx,
2821 napi_tx ? napi_weight : 0);
2822
2823 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
2824 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
2825 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
2826
2827 u64_stats_init(&vi->rq[i].stats.syncp);
2828 u64_stats_init(&vi->sq[i].stats.syncp);
2829 }
2830
2831 return 0;
2832
2833 err_rq:
2834 kfree(vi->sq);
2835 err_sq:
2836 kfree(vi->ctrl);
2837 err_ctrl:
2838 return -ENOMEM;
2839 }
2840
2841 static int init_vqs(struct virtnet_info *vi)
2842 {
2843 int ret;
2844
2845 /* Allocate send & receive queues */
2846 ret = virtnet_alloc_queues(vi);
2847 if (ret)
2848 goto err;
2849
2850 ret = virtnet_find_vqs(vi);
2851 if (ret)
2852 goto err_free;
2853
2854 get_online_cpus();
2855 virtnet_set_affinity(vi);
2856 put_online_cpus();
2857
2858 return 0;
2859
2860 err_free:
2861 virtnet_free_queues(vi);
2862 err:
2863 return ret;
2864 }
2865
2866 #ifdef CONFIG_SYSFS
2867 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
2868 char *buf)
2869 {
2870 struct virtnet_info *vi = netdev_priv(queue->dev);
2871 unsigned int queue_index = get_netdev_rx_queue_index(queue);
2872 unsigned int headroom = virtnet_get_headroom(vi);
2873 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
2874 struct ewma_pkt_len *avg;
2875
2876 BUG_ON(queue_index >= vi->max_queue_pairs);
2877 avg = &vi->rq[queue_index].mrg_avg_pkt_len;
2878 return sprintf(buf, "%u\n",
2879 get_mergeable_buf_len(&vi->rq[queue_index], avg,
2880 SKB_DATA_ALIGN(headroom + tailroom)));
2881 }
2882
2883 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
2884 __ATTR_RO(mergeable_rx_buffer_size);
2885
2886 static struct attribute *virtio_net_mrg_rx_attrs[] = {
2887 &mergeable_rx_buffer_size_attribute.attr,
2888 NULL
2889 };
2890
2891 static const struct attribute_group virtio_net_mrg_rx_group = {
2892 .name = "virtio_net",
2893 .attrs = virtio_net_mrg_rx_attrs
2894 };
2895 #endif
2896
2897 static bool virtnet_fail_on_feature(struct virtio_device *vdev,
2898 unsigned int fbit,
2899 const char *fname, const char *dname)
2900 {
2901 if (!virtio_has_feature(vdev, fbit))
2902 return false;
2903
2904 dev_err(&vdev->dev, "device advertises feature %s but not %s",
2905 fname, dname);
2906
2907 return true;
2908 }
2909
2910 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
2911 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
2912
2913 static bool virtnet_validate_features(struct virtio_device *vdev)
2914 {
2915 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
2916 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
2917 "VIRTIO_NET_F_CTRL_VQ") ||
2918 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
2919 "VIRTIO_NET_F_CTRL_VQ") ||
2920 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
2921 "VIRTIO_NET_F_CTRL_VQ") ||
2922 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
2923 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
2924 "VIRTIO_NET_F_CTRL_VQ"))) {
2925 return false;
2926 }
2927
2928 return true;
2929 }
2930
2931 #define MIN_MTU ETH_MIN_MTU
2932 #define MAX_MTU ETH_MAX_MTU
2933
2934 static int virtnet_validate(struct virtio_device *vdev)
2935 {
2936 if (!vdev->config->get) {
2937 dev_err(&vdev->dev, "%s failure: config access disabled\n",
2938 __func__);
2939 return -EINVAL;
2940 }
2941
2942 if (!virtnet_validate_features(vdev))
2943 return -EINVAL;
2944
2945 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
2946 int mtu = virtio_cread16(vdev,
2947 offsetof(struct virtio_net_config,
2948 mtu));
2949 if (mtu < MIN_MTU)
2950 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
2951 }
2952
2953 return 0;
2954 }
2955
2956 static int virtnet_probe(struct virtio_device *vdev)
2957 {
2958 int i, err = -ENOMEM;
2959 struct net_device *dev;
2960 struct virtnet_info *vi;
2961 u16 max_queue_pairs;
2962 int mtu;
2963
2964 /* Find if host supports multiqueue virtio_net device */
2965 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
2966 struct virtio_net_config,
2967 max_virtqueue_pairs, &max_queue_pairs);
2968
2969 /* We need at least 2 queue's */
2970 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
2971 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
2972 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
2973 max_queue_pairs = 1;
2974
2975 /* Allocate ourselves a network device with room for our info */
2976 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
2977 if (!dev)
2978 return -ENOMEM;
2979
2980 /* Set up network device as normal. */
2981 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
2982 dev->netdev_ops = &virtnet_netdev;
2983 dev->features = NETIF_F_HIGHDMA;
2984
2985 dev->ethtool_ops = &virtnet_ethtool_ops;
2986 SET_NETDEV_DEV(dev, &vdev->dev);
2987
2988 /* Do we support "hardware" checksums? */
2989 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
2990 /* This opens up the world of extra features. */
2991 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2992 if (csum)
2993 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
2994
2995 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
2996 dev->hw_features |= NETIF_F_TSO
2997 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
2998 }
2999 /* Individual feature bits: what can host handle? */
3000 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
3001 dev->hw_features |= NETIF_F_TSO;
3002 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
3003 dev->hw_features |= NETIF_F_TSO6;
3004 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
3005 dev->hw_features |= NETIF_F_TSO_ECN;
3006
3007 dev->features |= NETIF_F_GSO_ROBUST;
3008
3009 if (gso)
3010 dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
3011 /* (!csum && gso) case will be fixed by register_netdev() */
3012 }
3013 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
3014 dev->features |= NETIF_F_RXCSUM;
3015 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3016 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6))
3017 dev->features |= NETIF_F_LRO;
3018 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS))
3019 dev->hw_features |= NETIF_F_LRO;
3020
3021 dev->vlan_features = dev->features;
3022
3023 /* MTU range: 68 - 65535 */
3024 dev->min_mtu = MIN_MTU;
3025 dev->max_mtu = MAX_MTU;
3026
3027 /* Configuration may specify what MAC to use. Otherwise random. */
3028 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
3029 virtio_cread_bytes(vdev,
3030 offsetof(struct virtio_net_config, mac),
3031 dev->dev_addr, dev->addr_len);
3032 else
3033 eth_hw_addr_random(dev);
3034
3035 /* Set up our device-specific information */
3036 vi = netdev_priv(dev);
3037 vi->dev = dev;
3038 vi->vdev = vdev;
3039 vdev->priv = vi;
3040
3041 INIT_WORK(&vi->config_work, virtnet_config_changed_work);
3042
3043 /* If we can receive ANY GSO packets, we must allocate large ones. */
3044 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
3045 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
3046 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
3047 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
3048 vi->big_packets = true;
3049
3050 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
3051 vi->mergeable_rx_bufs = true;
3052
3053 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
3054 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
3055 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
3056 else
3057 vi->hdr_len = sizeof(struct virtio_net_hdr);
3058
3059 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
3060 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
3061 vi->any_header_sg = true;
3062
3063 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
3064 vi->has_cvq = true;
3065
3066 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
3067 mtu = virtio_cread16(vdev,
3068 offsetof(struct virtio_net_config,
3069 mtu));
3070 if (mtu < dev->min_mtu) {
3071 /* Should never trigger: MTU was previously validated
3072 * in virtnet_validate.
3073 */
3074 dev_err(&vdev->dev,
3075 "device MTU appears to have changed it is now %d < %d",
3076 mtu, dev->min_mtu);
3077 goto free;
3078 }
3079
3080 dev->mtu = mtu;
3081 dev->max_mtu = mtu;
3082
3083 /* TODO: size buffers correctly in this case. */
3084 if (dev->mtu > ETH_DATA_LEN)
3085 vi->big_packets = true;
3086 }
3087
3088 if (vi->any_header_sg)
3089 dev->needed_headroom = vi->hdr_len;
3090
3091 /* Enable multiqueue by default */
3092 if (num_online_cpus() >= max_queue_pairs)
3093 vi->curr_queue_pairs = max_queue_pairs;
3094 else
3095 vi->curr_queue_pairs = num_online_cpus();
3096 vi->max_queue_pairs = max_queue_pairs;
3097
3098 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */
3099 err = init_vqs(vi);
3100 if (err)
3101 goto free;
3102
3103 #ifdef CONFIG_SYSFS
3104 if (vi->mergeable_rx_bufs)
3105 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
3106 #endif
3107 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
3108 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
3109
3110 virtnet_init_settings(dev);
3111
3112 if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
3113 vi->failover = net_failover_create(vi->dev);
3114 if (IS_ERR(vi->failover)) {
3115 err = PTR_ERR(vi->failover);
3116 goto free_vqs;
3117 }
3118 }
3119
3120 err = register_netdev(dev);
3121 if (err) {
3122 pr_debug("virtio_net: registering device failed\n");
3123 goto free_failover;
3124 }
3125
3126 virtio_device_ready(vdev);
3127
3128 err = virtnet_cpu_notif_add(vi);
3129 if (err) {
3130 pr_debug("virtio_net: registering cpu notifier failed\n");
3131 goto free_unregister_netdev;
3132 }
3133
3134 virtnet_set_queues(vi, vi->curr_queue_pairs);
3135
3136 /* Assume link up if device can't report link status,
3137 otherwise get link status from config. */
3138 netif_carrier_off(dev);
3139 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
3140 schedule_work(&vi->config_work);
3141 } else {
3142 vi->status = VIRTIO_NET_S_LINK_UP;
3143 virtnet_update_settings(vi);
3144 netif_carrier_on(dev);
3145 }
3146
3147 for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
3148 if (virtio_has_feature(vi->vdev, guest_offloads[i]))
3149 set_bit(guest_offloads[i], &vi->guest_offloads);
3150 vi->guest_offloads_capable = vi->guest_offloads;
3151
3152 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
3153 dev->name, max_queue_pairs);
3154
3155 return 0;
3156
3157 free_unregister_netdev:
3158 vi->vdev->config->reset(vdev);
3159
3160 unregister_netdev(dev);
3161 free_failover:
3162 net_failover_destroy(vi->failover);
3163 free_vqs:
3164 cancel_delayed_work_sync(&vi->refill);
3165 free_receive_page_frags(vi);
3166 virtnet_del_vqs(vi);
3167 free:
3168 free_netdev(dev);
3169 return err;
3170 }
3171
3172 static void remove_vq_common(struct virtnet_info *vi)
3173 {
3174 vi->vdev->config->reset(vi->vdev);
3175
3176 /* Free unused buffers in both send and recv, if any. */
3177 free_unused_bufs(vi);
3178
3179 free_receive_bufs(vi);
3180
3181 free_receive_page_frags(vi);
3182
3183 virtnet_del_vqs(vi);
3184 }
3185
3186 static void virtnet_remove(struct virtio_device *vdev)
3187 {
3188 struct virtnet_info *vi = vdev->priv;
3189
3190 virtnet_cpu_notif_remove(vi);
3191
3192 /* Make sure no work handler is accessing the device. */
3193 flush_work(&vi->config_work);
3194
3195 unregister_netdev(vi->dev);
3196
3197 net_failover_destroy(vi->failover);
3198
3199 remove_vq_common(vi);
3200
3201 free_netdev(vi->dev);
3202 }
3203
3204 static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
3205 {
3206 struct virtnet_info *vi = vdev->priv;
3207
3208 virtnet_cpu_notif_remove(vi);
3209 virtnet_freeze_down(vdev);
3210 remove_vq_common(vi);
3211
3212 return 0;
3213 }
3214
3215 static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
3216 {
3217 struct virtnet_info *vi = vdev->priv;
3218 int err;
3219
3220 err = virtnet_restore_up(vdev);
3221 if (err)
3222 return err;
3223 virtnet_set_queues(vi, vi->curr_queue_pairs);
3224
3225 err = virtnet_cpu_notif_add(vi);
3226 if (err)
3227 return err;
3228
3229 return 0;
3230 }
3231
3232 static struct virtio_device_id id_table[] = {
3233 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
3234 { 0 },
3235 };
3236
3237 #define VIRTNET_FEATURES \
3238 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
3239 VIRTIO_NET_F_MAC, \
3240 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
3241 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
3242 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
3243 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
3244 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
3245 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
3246 VIRTIO_NET_F_CTRL_MAC_ADDR, \
3247 VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
3248 VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY
3249
3250 static unsigned int features[] = {
3251 VIRTNET_FEATURES,
3252 };
3253
3254 static unsigned int features_legacy[] = {
3255 VIRTNET_FEATURES,
3256 VIRTIO_NET_F_GSO,
3257 VIRTIO_F_ANY_LAYOUT,
3258 };
3259
3260 static struct virtio_driver virtio_net_driver = {
3261 .feature_table = features,
3262 .feature_table_size = ARRAY_SIZE(features),
3263 .feature_table_legacy = features_legacy,
3264 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
3265 .driver.name = KBUILD_MODNAME,
3266 .driver.owner = THIS_MODULE,
3267 .id_table = id_table,
3268 .validate = virtnet_validate,
3269 .probe = virtnet_probe,
3270 .remove = virtnet_remove,
3271 .config_changed = virtnet_config_changed,
3272 #ifdef CONFIG_PM_SLEEP
3273 .freeze = virtnet_freeze,
3274 .restore = virtnet_restore,
3275 #endif
3276 };
3277
3278 static __init int virtio_net_driver_init(void)
3279 {
3280 int ret;
3281
3282 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
3283 virtnet_cpu_online,
3284 virtnet_cpu_down_prep);
3285 if (ret < 0)
3286 goto out;
3287 virtionet_online = ret;
3288 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
3289 NULL, virtnet_cpu_dead);
3290 if (ret)
3291 goto err_dead;
3292
3293 ret = register_virtio_driver(&virtio_net_driver);
3294 if (ret)
3295 goto err_virtio;
3296 return 0;
3297 err_virtio:
3298 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
3299 err_dead:
3300 cpuhp_remove_multi_state(virtionet_online);
3301 out:
3302 return ret;
3303 }
3304 module_init(virtio_net_driver_init);
3305
3306 static __exit void virtio_net_driver_exit(void)
3307 {
3308 unregister_virtio_driver(&virtio_net_driver);
3309 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
3310 cpuhp_remove_multi_state(virtionet_online);
3311 }
3312 module_exit(virtio_net_driver_exit);
3313
3314 MODULE_DEVICE_TABLE(virtio, id_table);
3315 MODULE_DESCRIPTION("Virtio network driver");
3316 MODULE_LICENSE("GPL");
Linux with added FPC-III support