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12#include <linux/netdevice.h>
13#include <linux/slab.h>
14#include <linux/ethtool.h>
15#include <linux/etherdevice.h>
16#include <linux/u64_stats_sync.h>
17
18#include <net/rtnetlink.h>
19#include <net/dst.h>
20#include <net/xfrm.h>
21#include <net/xdp.h>
22#include <linux/veth.h>
23#include <linux/module.h>
24#include <linux/bpf.h>
25#include <linux/filter.h>
26#include <linux/ptr_ring.h>
27#include <linux/bpf_trace.h>
28#include <linux/net_tstamp.h>
29
30#define DRV_NAME "veth"
31#define DRV_VERSION "1.0"
32
33#define VETH_XDP_FLAG BIT(0)
34#define VETH_RING_SIZE 256
35#define VETH_XDP_HEADROOM (XDP_PACKET_HEADROOM + NET_IP_ALIGN)
36
37#define VETH_XDP_TX_BULK_SIZE 16
38#define VETH_XDP_BATCH 16
39
40struct veth_stats {
41 u64 rx_drops;
42
43 u64 xdp_packets;
44 u64 xdp_bytes;
45 u64 xdp_redirect;
46 u64 xdp_drops;
47 u64 xdp_tx;
48 u64 xdp_tx_err;
49 u64 peer_tq_xdp_xmit;
50 u64 peer_tq_xdp_xmit_err;
51};
52
53struct veth_rq_stats {
54 struct veth_stats vs;
55 struct u64_stats_sync syncp;
56};
57
58struct veth_rq {
59 struct napi_struct xdp_napi;
60 struct napi_struct __rcu *napi;
61 struct net_device *dev;
62 struct bpf_prog __rcu *xdp_prog;
63 struct xdp_mem_info xdp_mem;
64 struct veth_rq_stats stats;
65 bool rx_notify_masked;
66 struct ptr_ring xdp_ring;
67 struct xdp_rxq_info xdp_rxq;
68};
69
70struct veth_priv {
71 struct net_device __rcu *peer;
72 atomic64_t dropped;
73 struct bpf_prog *_xdp_prog;
74 struct veth_rq *rq;
75 unsigned int requested_headroom;
76};
77
78struct veth_xdp_tx_bq {
79 struct xdp_frame *q[VETH_XDP_TX_BULK_SIZE];
80 unsigned int count;
81};
82
83
84
85
86
87struct veth_q_stat_desc {
88 char desc[ETH_GSTRING_LEN];
89 size_t offset;
90};
91
92#define VETH_RQ_STAT(m) offsetof(struct veth_stats, m)
93
94static const struct veth_q_stat_desc veth_rq_stats_desc[] = {
95 { "xdp_packets", VETH_RQ_STAT(xdp_packets) },
96 { "xdp_bytes", VETH_RQ_STAT(xdp_bytes) },
97 { "drops", VETH_RQ_STAT(rx_drops) },
98 { "xdp_redirect", VETH_RQ_STAT(xdp_redirect) },
99 { "xdp_drops", VETH_RQ_STAT(xdp_drops) },
100 { "xdp_tx", VETH_RQ_STAT(xdp_tx) },
101 { "xdp_tx_errors", VETH_RQ_STAT(xdp_tx_err) },
102};
103
104#define VETH_RQ_STATS_LEN ARRAY_SIZE(veth_rq_stats_desc)
105
106static const struct veth_q_stat_desc veth_tq_stats_desc[] = {
107 { "xdp_xmit", VETH_RQ_STAT(peer_tq_xdp_xmit) },
108 { "xdp_xmit_errors", VETH_RQ_STAT(peer_tq_xdp_xmit_err) },
109};
110
111#define VETH_TQ_STATS_LEN ARRAY_SIZE(veth_tq_stats_desc)
112
113static struct {
114 const char string[ETH_GSTRING_LEN];
115} ethtool_stats_keys[] = {
116 { "peer_ifindex" },
117};
118
119static int veth_get_link_ksettings(struct net_device *dev,
120 struct ethtool_link_ksettings *cmd)
121{
122 cmd->base.speed = SPEED_10000;
123 cmd->base.duplex = DUPLEX_FULL;
124 cmd->base.port = PORT_TP;
125 cmd->base.autoneg = AUTONEG_DISABLE;
126 return 0;
127}
128
129static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
130{
131 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
132 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
133}
134
135static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
136{
137 u8 *p = buf;
138 int i, j;
139
140 switch(stringset) {
141 case ETH_SS_STATS:
142 memcpy(p, ðtool_stats_keys, sizeof(ethtool_stats_keys));
143 p += sizeof(ethtool_stats_keys);
144 for (i = 0; i < dev->real_num_rx_queues; i++)
145 for (j = 0; j < VETH_RQ_STATS_LEN; j++)
146 ethtool_sprintf(&p, "rx_queue_%u_%.18s",
147 i, veth_rq_stats_desc[j].desc);
148
149 for (i = 0; i < dev->real_num_tx_queues; i++)
150 for (j = 0; j < VETH_TQ_STATS_LEN; j++)
151 ethtool_sprintf(&p, "tx_queue_%u_%.18s",
152 i, veth_tq_stats_desc[j].desc);
153 break;
154 }
155}
156
157static int veth_get_sset_count(struct net_device *dev, int sset)
158{
159 switch (sset) {
160 case ETH_SS_STATS:
161 return ARRAY_SIZE(ethtool_stats_keys) +
162 VETH_RQ_STATS_LEN * dev->real_num_rx_queues +
163 VETH_TQ_STATS_LEN * dev->real_num_tx_queues;
164 default:
165 return -EOPNOTSUPP;
166 }
167}
168
169static void veth_get_ethtool_stats(struct net_device *dev,
170 struct ethtool_stats *stats, u64 *data)
171{
172 struct veth_priv *rcv_priv, *priv = netdev_priv(dev);
173 struct net_device *peer = rtnl_dereference(priv->peer);
174 int i, j, idx;
175
176 data[0] = peer ? peer->ifindex : 0;
177 idx = 1;
178 for (i = 0; i < dev->real_num_rx_queues; i++) {
179 const struct veth_rq_stats *rq_stats = &priv->rq[i].stats;
180 const void *stats_base = (void *)&rq_stats->vs;
181 unsigned int start;
182 size_t offset;
183
184 do {
185 start = u64_stats_fetch_begin_irq(&rq_stats->syncp);
186 for (j = 0; j < VETH_RQ_STATS_LEN; j++) {
187 offset = veth_rq_stats_desc[j].offset;
188 data[idx + j] = *(u64 *)(stats_base + offset);
189 }
190 } while (u64_stats_fetch_retry_irq(&rq_stats->syncp, start));
191 idx += VETH_RQ_STATS_LEN;
192 }
193
194 if (!peer)
195 return;
196
197 rcv_priv = netdev_priv(peer);
198 for (i = 0; i < peer->real_num_rx_queues; i++) {
199 const struct veth_rq_stats *rq_stats = &rcv_priv->rq[i].stats;
200 const void *base = (void *)&rq_stats->vs;
201 unsigned int start, tx_idx = idx;
202 size_t offset;
203
204 tx_idx += (i % dev->real_num_tx_queues) * VETH_TQ_STATS_LEN;
205 do {
206 start = u64_stats_fetch_begin_irq(&rq_stats->syncp);
207 for (j = 0; j < VETH_TQ_STATS_LEN; j++) {
208 offset = veth_tq_stats_desc[j].offset;
209 data[tx_idx + j] += *(u64 *)(base + offset);
210 }
211 } while (u64_stats_fetch_retry_irq(&rq_stats->syncp, start));
212 }
213}
214
215static void veth_get_channels(struct net_device *dev,
216 struct ethtool_channels *channels)
217{
218 channels->tx_count = dev->real_num_tx_queues;
219 channels->rx_count = dev->real_num_rx_queues;
220 channels->max_tx = dev->num_tx_queues;
221 channels->max_rx = dev->num_rx_queues;
222}
223
224static int veth_set_channels(struct net_device *dev,
225 struct ethtool_channels *ch);
226
227static const struct ethtool_ops veth_ethtool_ops = {
228 .get_drvinfo = veth_get_drvinfo,
229 .get_link = ethtool_op_get_link,
230 .get_strings = veth_get_strings,
231 .get_sset_count = veth_get_sset_count,
232 .get_ethtool_stats = veth_get_ethtool_stats,
233 .get_link_ksettings = veth_get_link_ksettings,
234 .get_ts_info = ethtool_op_get_ts_info,
235 .get_channels = veth_get_channels,
236 .set_channels = veth_set_channels,
237};
238
239
240
241static bool veth_is_xdp_frame(void *ptr)
242{
243 return (unsigned long)ptr & VETH_XDP_FLAG;
244}
245
246static struct xdp_frame *veth_ptr_to_xdp(void *ptr)
247{
248 return (void *)((unsigned long)ptr & ~VETH_XDP_FLAG);
249}
250
251static void *veth_xdp_to_ptr(struct xdp_frame *xdp)
252{
253 return (void *)((unsigned long)xdp | VETH_XDP_FLAG);
254}
255
256static void veth_ptr_free(void *ptr)
257{
258 if (veth_is_xdp_frame(ptr))
259 xdp_return_frame(veth_ptr_to_xdp(ptr));
260 else
261 kfree_skb(ptr);
262}
263
264static void __veth_xdp_flush(struct veth_rq *rq)
265{
266
267 smp_mb();
268 if (!READ_ONCE(rq->rx_notify_masked) &&
269 napi_schedule_prep(&rq->xdp_napi)) {
270 WRITE_ONCE(rq->rx_notify_masked, true);
271 __napi_schedule(&rq->xdp_napi);
272 }
273}
274
275static int veth_xdp_rx(struct veth_rq *rq, struct sk_buff *skb)
276{
277 if (unlikely(ptr_ring_produce(&rq->xdp_ring, skb))) {
278 dev_kfree_skb_any(skb);
279 return NET_RX_DROP;
280 }
281
282 return NET_RX_SUCCESS;
283}
284
285static int veth_forward_skb(struct net_device *dev, struct sk_buff *skb,
286 struct veth_rq *rq, bool xdp)
287{
288 return __dev_forward_skb(dev, skb) ?: xdp ?
289 veth_xdp_rx(rq, skb) :
290 __netif_rx(skb);
291}
292
293
294
295
296
297
298
299
300
301
302
303static bool veth_skb_is_eligible_for_gro(const struct net_device *dev,
304 const struct net_device *rcv,
305 const struct sk_buff *skb)
306{
307 return !(dev->features & NETIF_F_ALL_TSO) ||
308 (skb->destructor == sock_wfree &&
309 rcv->features & (NETIF_F_GRO_FRAGLIST | NETIF_F_GRO_UDP_FWD));
310}
311
312static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
313{
314 struct veth_priv *rcv_priv, *priv = netdev_priv(dev);
315 struct veth_rq *rq = NULL;
316 struct net_device *rcv;
317 int length = skb->len;
318 bool use_napi = false;
319 int rxq;
320
321 rcu_read_lock();
322 rcv = rcu_dereference(priv->peer);
323 if (unlikely(!rcv) || !pskb_may_pull(skb, ETH_HLEN)) {
324 kfree_skb(skb);
325 goto drop;
326 }
327
328 rcv_priv = netdev_priv(rcv);
329 rxq = skb_get_queue_mapping(skb);
330 if (rxq < rcv->real_num_rx_queues) {
331 rq = &rcv_priv->rq[rxq];
332
333
334
335
336
337 use_napi = rcu_access_pointer(rq->napi) &&
338 veth_skb_is_eligible_for_gro(dev, rcv, skb);
339 }
340
341 skb_tx_timestamp(skb);
342 if (likely(veth_forward_skb(rcv, skb, rq, use_napi) == NET_RX_SUCCESS)) {
343 if (!use_napi)
344 dev_lstats_add(dev, length);
345 } else {
346drop:
347 atomic64_inc(&priv->dropped);
348 }
349
350 if (use_napi)
351 __veth_xdp_flush(rq);
352
353 rcu_read_unlock();
354
355 return NETDEV_TX_OK;
356}
357
358static u64 veth_stats_tx(struct net_device *dev, u64 *packets, u64 *bytes)
359{
360 struct veth_priv *priv = netdev_priv(dev);
361
362 dev_lstats_read(dev, packets, bytes);
363 return atomic64_read(&priv->dropped);
364}
365
366static void veth_stats_rx(struct veth_stats *result, struct net_device *dev)
367{
368 struct veth_priv *priv = netdev_priv(dev);
369 int i;
370
371 result->peer_tq_xdp_xmit_err = 0;
372 result->xdp_packets = 0;
373 result->xdp_tx_err = 0;
374 result->xdp_bytes = 0;
375 result->rx_drops = 0;
376 for (i = 0; i < dev->num_rx_queues; i++) {
377 u64 packets, bytes, drops, xdp_tx_err, peer_tq_xdp_xmit_err;
378 struct veth_rq_stats *stats = &priv->rq[i].stats;
379 unsigned int start;
380
381 do {
382 start = u64_stats_fetch_begin_irq(&stats->syncp);
383 peer_tq_xdp_xmit_err = stats->vs.peer_tq_xdp_xmit_err;
384 xdp_tx_err = stats->vs.xdp_tx_err;
385 packets = stats->vs.xdp_packets;
386 bytes = stats->vs.xdp_bytes;
387 drops = stats->vs.rx_drops;
388 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
389 result->peer_tq_xdp_xmit_err += peer_tq_xdp_xmit_err;
390 result->xdp_tx_err += xdp_tx_err;
391 result->xdp_packets += packets;
392 result->xdp_bytes += bytes;
393 result->rx_drops += drops;
394 }
395}
396
397static void veth_get_stats64(struct net_device *dev,
398 struct rtnl_link_stats64 *tot)
399{
400 struct veth_priv *priv = netdev_priv(dev);
401 struct net_device *peer;
402 struct veth_stats rx;
403 u64 packets, bytes;
404
405 tot->tx_dropped = veth_stats_tx(dev, &packets, &bytes);
406 tot->tx_bytes = bytes;
407 tot->tx_packets = packets;
408
409 veth_stats_rx(&rx, dev);
410 tot->tx_dropped += rx.xdp_tx_err;
411 tot->rx_dropped = rx.rx_drops + rx.peer_tq_xdp_xmit_err;
412 tot->rx_bytes = rx.xdp_bytes;
413 tot->rx_packets = rx.xdp_packets;
414
415 rcu_read_lock();
416 peer = rcu_dereference(priv->peer);
417 if (peer) {
418 veth_stats_tx(peer, &packets, &bytes);
419 tot->rx_bytes += bytes;
420 tot->rx_packets += packets;
421
422 veth_stats_rx(&rx, peer);
423 tot->tx_dropped += rx.peer_tq_xdp_xmit_err;
424 tot->rx_dropped += rx.xdp_tx_err;
425 tot->tx_bytes += rx.xdp_bytes;
426 tot->tx_packets += rx.xdp_packets;
427 }
428 rcu_read_unlock();
429}
430
431
432static void veth_set_multicast_list(struct net_device *dev)
433{
434}
435
436static int veth_select_rxq(struct net_device *dev)
437{
438 return smp_processor_id() % dev->real_num_rx_queues;
439}
440
441static struct net_device *veth_peer_dev(struct net_device *dev)
442{
443 struct veth_priv *priv = netdev_priv(dev);
444
445
446 return rcu_dereference(priv->peer);
447}
448
449static int veth_xdp_xmit(struct net_device *dev, int n,
450 struct xdp_frame **frames,
451 u32 flags, bool ndo_xmit)
452{
453 struct veth_priv *rcv_priv, *priv = netdev_priv(dev);
454 int i, ret = -ENXIO, nxmit = 0;
455 struct net_device *rcv;
456 unsigned int max_len;
457 struct veth_rq *rq;
458
459 if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
460 return -EINVAL;
461
462 rcu_read_lock();
463 rcv = rcu_dereference(priv->peer);
464 if (unlikely(!rcv))
465 goto out;
466
467 rcv_priv = netdev_priv(rcv);
468 rq = &rcv_priv->rq[veth_select_rxq(rcv)];
469
470
471
472 if (!rcu_access_pointer(rq->napi))
473 goto out;
474
475 max_len = rcv->mtu + rcv->hard_header_len + VLAN_HLEN;
476
477 spin_lock(&rq->xdp_ring.producer_lock);
478 for (i = 0; i < n; i++) {
479 struct xdp_frame *frame = frames[i];
480 void *ptr = veth_xdp_to_ptr(frame);
481
482 if (unlikely(xdp_get_frame_len(frame) > max_len ||
483 __ptr_ring_produce(&rq->xdp_ring, ptr)))
484 break;
485 nxmit++;
486 }
487 spin_unlock(&rq->xdp_ring.producer_lock);
488
489 if (flags & XDP_XMIT_FLUSH)
490 __veth_xdp_flush(rq);
491
492 ret = nxmit;
493 if (ndo_xmit) {
494 u64_stats_update_begin(&rq->stats.syncp);
495 rq->stats.vs.peer_tq_xdp_xmit += nxmit;
496 rq->stats.vs.peer_tq_xdp_xmit_err += n - nxmit;
497 u64_stats_update_end(&rq->stats.syncp);
498 }
499
500out:
501 rcu_read_unlock();
502
503 return ret;
504}
505
506static int veth_ndo_xdp_xmit(struct net_device *dev, int n,
507 struct xdp_frame **frames, u32 flags)
508{
509 int err;
510
511 err = veth_xdp_xmit(dev, n, frames, flags, true);
512 if (err < 0) {
513 struct veth_priv *priv = netdev_priv(dev);
514
515 atomic64_add(n, &priv->dropped);
516 }
517
518 return err;
519}
520
521static void veth_xdp_flush_bq(struct veth_rq *rq, struct veth_xdp_tx_bq *bq)
522{
523 int sent, i, err = 0, drops;
524
525 sent = veth_xdp_xmit(rq->dev, bq->count, bq->q, 0, false);
526 if (sent < 0) {
527 err = sent;
528 sent = 0;
529 }
530
531 for (i = sent; unlikely(i < bq->count); i++)
532 xdp_return_frame(bq->q[i]);
533
534 drops = bq->count - sent;
535 trace_xdp_bulk_tx(rq->dev, sent, drops, err);
536
537 u64_stats_update_begin(&rq->stats.syncp);
538 rq->stats.vs.xdp_tx += sent;
539 rq->stats.vs.xdp_tx_err += drops;
540 u64_stats_update_end(&rq->stats.syncp);
541
542 bq->count = 0;
543}
544
545static void veth_xdp_flush(struct veth_rq *rq, struct veth_xdp_tx_bq *bq)
546{
547 struct veth_priv *rcv_priv, *priv = netdev_priv(rq->dev);
548 struct net_device *rcv;
549 struct veth_rq *rcv_rq;
550
551 rcu_read_lock();
552 veth_xdp_flush_bq(rq, bq);
553 rcv = rcu_dereference(priv->peer);
554 if (unlikely(!rcv))
555 goto out;
556
557 rcv_priv = netdev_priv(rcv);
558 rcv_rq = &rcv_priv->rq[veth_select_rxq(rcv)];
559
560 if (unlikely(!rcu_access_pointer(rcv_rq->xdp_prog)))
561 goto out;
562
563 __veth_xdp_flush(rcv_rq);
564out:
565 rcu_read_unlock();
566}
567
568static int veth_xdp_tx(struct veth_rq *rq, struct xdp_buff *xdp,
569 struct veth_xdp_tx_bq *bq)
570{
571 struct xdp_frame *frame = xdp_convert_buff_to_frame(xdp);
572
573 if (unlikely(!frame))
574 return -EOVERFLOW;
575
576 if (unlikely(bq->count == VETH_XDP_TX_BULK_SIZE))
577 veth_xdp_flush_bq(rq, bq);
578
579 bq->q[bq->count++] = frame;
580
581 return 0;
582}
583
584static struct xdp_frame *veth_xdp_rcv_one(struct veth_rq *rq,
585 struct xdp_frame *frame,
586 struct veth_xdp_tx_bq *bq,
587 struct veth_stats *stats)
588{
589 struct xdp_frame orig_frame;
590 struct bpf_prog *xdp_prog;
591
592 rcu_read_lock();
593 xdp_prog = rcu_dereference(rq->xdp_prog);
594 if (likely(xdp_prog)) {
595 struct xdp_buff xdp;
596 u32 act;
597
598 xdp_convert_frame_to_buff(frame, &xdp);
599 xdp.rxq = &rq->xdp_rxq;
600
601 act = bpf_prog_run_xdp(xdp_prog, &xdp);
602
603 switch (act) {
604 case XDP_PASS:
605 if (xdp_update_frame_from_buff(&xdp, frame))
606 goto err_xdp;
607 break;
608 case XDP_TX:
609 orig_frame = *frame;
610 xdp.rxq->mem = frame->mem;
611 if (unlikely(veth_xdp_tx(rq, &xdp, bq) < 0)) {
612 trace_xdp_exception(rq->dev, xdp_prog, act);
613 frame = &orig_frame;
614 stats->rx_drops++;
615 goto err_xdp;
616 }
617 stats->xdp_tx++;
618 rcu_read_unlock();
619 goto xdp_xmit;
620 case XDP_REDIRECT:
621 orig_frame = *frame;
622 xdp.rxq->mem = frame->mem;
623 if (xdp_do_redirect(rq->dev, &xdp, xdp_prog)) {
624 frame = &orig_frame;
625 stats->rx_drops++;
626 goto err_xdp;
627 }
628 stats->xdp_redirect++;
629 rcu_read_unlock();
630 goto xdp_xmit;
631 default:
632 bpf_warn_invalid_xdp_action(rq->dev, xdp_prog, act);
633 fallthrough;
634 case XDP_ABORTED:
635 trace_xdp_exception(rq->dev, xdp_prog, act);
636 fallthrough;
637 case XDP_DROP:
638 stats->xdp_drops++;
639 goto err_xdp;
640 }
641 }
642 rcu_read_unlock();
643
644 return frame;
645err_xdp:
646 rcu_read_unlock();
647 xdp_return_frame(frame);
648xdp_xmit:
649 return NULL;
650}
651
652
653static void veth_xdp_rcv_bulk_skb(struct veth_rq *rq, void **frames,
654 int n_xdpf, struct veth_xdp_tx_bq *bq,
655 struct veth_stats *stats)
656{
657 void *skbs[VETH_XDP_BATCH];
658 int i;
659
660 if (xdp_alloc_skb_bulk(skbs, n_xdpf,
661 GFP_ATOMIC | __GFP_ZERO) < 0) {
662 for (i = 0; i < n_xdpf; i++)
663 xdp_return_frame(frames[i]);
664 stats->rx_drops += n_xdpf;
665
666 return;
667 }
668
669 for (i = 0; i < n_xdpf; i++) {
670 struct sk_buff *skb = skbs[i];
671
672 skb = __xdp_build_skb_from_frame(frames[i], skb,
673 rq->dev);
674 if (!skb) {
675 xdp_return_frame(frames[i]);
676 stats->rx_drops++;
677 continue;
678 }
679 napi_gro_receive(&rq->xdp_napi, skb);
680 }
681}
682
683static void veth_xdp_get(struct xdp_buff *xdp)
684{
685 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
686 int i;
687
688 get_page(virt_to_page(xdp->data));
689 if (likely(!xdp_buff_has_frags(xdp)))
690 return;
691
692 for (i = 0; i < sinfo->nr_frags; i++)
693 __skb_frag_ref(&sinfo->frags[i]);
694}
695
696static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq,
697 struct xdp_buff *xdp,
698 struct sk_buff **pskb)
699{
700 struct sk_buff *skb = *pskb;
701 u32 frame_sz;
702
703 if (skb_shared(skb) || skb_head_is_locked(skb) ||
704 skb_shinfo(skb)->nr_frags) {
705 u32 size, len, max_head_size, off;
706 struct sk_buff *nskb;
707 struct page *page;
708 int i, head_off;
709
710
711
712
713
714
715
716 max_head_size = SKB_WITH_OVERHEAD(PAGE_SIZE -
717 VETH_XDP_HEADROOM);
718 if (skb->len > PAGE_SIZE * MAX_SKB_FRAGS + max_head_size)
719 goto drop;
720
721
722 page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
723 if (!page)
724 goto drop;
725
726 nskb = build_skb(page_address(page), PAGE_SIZE);
727 if (!nskb) {
728 put_page(page);
729 goto drop;
730 }
731
732 skb_reserve(nskb, VETH_XDP_HEADROOM);
733 size = min_t(u32, skb->len, max_head_size);
734 if (skb_copy_bits(skb, 0, nskb->data, size)) {
735 consume_skb(nskb);
736 goto drop;
737 }
738 skb_put(nskb, size);
739
740 skb_copy_header(nskb, skb);
741 head_off = skb_headroom(nskb) - skb_headroom(skb);
742 skb_headers_offset_update(nskb, head_off);
743
744
745 off = size;
746 len = skb->len - off;
747
748 for (i = 0; i < MAX_SKB_FRAGS && off < skb->len; i++) {
749 page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
750 if (!page) {
751 consume_skb(nskb);
752 goto drop;
753 }
754
755 size = min_t(u32, len, PAGE_SIZE);
756 skb_add_rx_frag(nskb, i, page, 0, size, PAGE_SIZE);
757 if (skb_copy_bits(skb, off, page_address(page),
758 size)) {
759 consume_skb(nskb);
760 goto drop;
761 }
762
763 len -= size;
764 off += size;
765 }
766
767 consume_skb(skb);
768 skb = nskb;
769 } else if (skb_headroom(skb) < XDP_PACKET_HEADROOM &&
770 pskb_expand_head(skb, VETH_XDP_HEADROOM, 0, GFP_ATOMIC)) {
771 goto drop;
772 }
773
774
775 frame_sz = skb_end_pointer(skb) - skb->head;
776 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
777 xdp_init_buff(xdp, frame_sz, &rq->xdp_rxq);
778 xdp_prepare_buff(xdp, skb->head, skb_headroom(skb),
779 skb_headlen(skb), true);
780
781 if (skb_is_nonlinear(skb)) {
782 skb_shinfo(skb)->xdp_frags_size = skb->data_len;
783 xdp_buff_set_frags_flag(xdp);
784 } else {
785 xdp_buff_clear_frags_flag(xdp);
786 }
787 *pskb = skb;
788
789 return 0;
790drop:
791 consume_skb(skb);
792 *pskb = NULL;
793
794 return -ENOMEM;
795}
796
797static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq,
798 struct sk_buff *skb,
799 struct veth_xdp_tx_bq *bq,
800 struct veth_stats *stats)
801{
802 void *orig_data, *orig_data_end;
803 struct bpf_prog *xdp_prog;
804 struct xdp_buff xdp;
805 u32 act, metalen;
806 int off;
807
808 skb_prepare_for_gro(skb);
809
810 rcu_read_lock();
811 xdp_prog = rcu_dereference(rq->xdp_prog);
812 if (unlikely(!xdp_prog)) {
813 rcu_read_unlock();
814 goto out;
815 }
816
817 __skb_push(skb, skb->data - skb_mac_header(skb));
818 if (veth_convert_skb_to_xdp_buff(rq, &xdp, &skb))
819 goto drop;
820
821 orig_data = xdp.data;
822 orig_data_end = xdp.data_end;
823
824 act = bpf_prog_run_xdp(xdp_prog, &xdp);
825
826 switch (act) {
827 case XDP_PASS:
828 break;
829 case XDP_TX:
830 veth_xdp_get(&xdp);
831 consume_skb(skb);
832 xdp.rxq->mem = rq->xdp_mem;
833 if (unlikely(veth_xdp_tx(rq, &xdp, bq) < 0)) {
834 trace_xdp_exception(rq->dev, xdp_prog, act);
835 stats->rx_drops++;
836 goto err_xdp;
837 }
838 stats->xdp_tx++;
839 rcu_read_unlock();
840 goto xdp_xmit;
841 case XDP_REDIRECT:
842 veth_xdp_get(&xdp);
843 consume_skb(skb);
844 xdp.rxq->mem = rq->xdp_mem;
845 if (xdp_do_redirect(rq->dev, &xdp, xdp_prog)) {
846 stats->rx_drops++;
847 goto err_xdp;
848 }
849 stats->xdp_redirect++;
850 rcu_read_unlock();
851 goto xdp_xmit;
852 default:
853 bpf_warn_invalid_xdp_action(rq->dev, xdp_prog, act);
854 fallthrough;
855 case XDP_ABORTED:
856 trace_xdp_exception(rq->dev, xdp_prog, act);
857 fallthrough;
858 case XDP_DROP:
859 stats->xdp_drops++;
860 goto xdp_drop;
861 }
862 rcu_read_unlock();
863
864
865 off = orig_data - xdp.data;
866 if (off > 0)
867 __skb_push(skb, off);
868 else if (off < 0)
869 __skb_pull(skb, -off);
870
871 skb_reset_mac_header(skb);
872
873
874 off = xdp.data_end - orig_data_end;
875 if (off != 0)
876 __skb_put(skb, off);
877
878
879
880
881 if (xdp_buff_has_frags(&xdp))
882 skb->data_len = skb_shinfo(skb)->xdp_frags_size;
883 else
884 skb->data_len = 0;
885
886 skb->protocol = eth_type_trans(skb, rq->dev);
887
888 metalen = xdp.data - xdp.data_meta;
889 if (metalen)
890 skb_metadata_set(skb, metalen);
891out:
892 return skb;
893drop:
894 stats->rx_drops++;
895xdp_drop:
896 rcu_read_unlock();
897 kfree_skb(skb);
898 return NULL;
899err_xdp:
900 rcu_read_unlock();
901 xdp_return_buff(&xdp);
902xdp_xmit:
903 return NULL;
904}
905
906static int veth_xdp_rcv(struct veth_rq *rq, int budget,
907 struct veth_xdp_tx_bq *bq,
908 struct veth_stats *stats)
909{
910 int i, done = 0, n_xdpf = 0;
911 void *xdpf[VETH_XDP_BATCH];
912
913 for (i = 0; i < budget; i++) {
914 void *ptr = __ptr_ring_consume(&rq->xdp_ring);
915
916 if (!ptr)
917 break;
918
919 if (veth_is_xdp_frame(ptr)) {
920
921 struct xdp_frame *frame = veth_ptr_to_xdp(ptr);
922
923 stats->xdp_bytes += xdp_get_frame_len(frame);
924 frame = veth_xdp_rcv_one(rq, frame, bq, stats);
925 if (frame) {
926
927 xdpf[n_xdpf++] = frame;
928 if (n_xdpf == VETH_XDP_BATCH) {
929 veth_xdp_rcv_bulk_skb(rq, xdpf, n_xdpf,
930 bq, stats);
931 n_xdpf = 0;
932 }
933 }
934 } else {
935
936 struct sk_buff *skb = ptr;
937
938 stats->xdp_bytes += skb->len;
939 skb = veth_xdp_rcv_skb(rq, skb, bq, stats);
940 if (skb) {
941 if (skb_shared(skb) || skb_unclone(skb, GFP_ATOMIC))
942 netif_receive_skb(skb);
943 else
944 napi_gro_receive(&rq->xdp_napi, skb);
945 }
946 }
947 done++;
948 }
949
950 if (n_xdpf)
951 veth_xdp_rcv_bulk_skb(rq, xdpf, n_xdpf, bq, stats);
952
953 u64_stats_update_begin(&rq->stats.syncp);
954 rq->stats.vs.xdp_redirect += stats->xdp_redirect;
955 rq->stats.vs.xdp_bytes += stats->xdp_bytes;
956 rq->stats.vs.xdp_drops += stats->xdp_drops;
957 rq->stats.vs.rx_drops += stats->rx_drops;
958 rq->stats.vs.xdp_packets += done;
959 u64_stats_update_end(&rq->stats.syncp);
960
961 return done;
962}
963
964static int veth_poll(struct napi_struct *napi, int budget)
965{
966 struct veth_rq *rq =
967 container_of(napi, struct veth_rq, xdp_napi);
968 struct veth_stats stats = {};
969 struct veth_xdp_tx_bq bq;
970 int done;
971
972 bq.count = 0;
973
974 xdp_set_return_frame_no_direct();
975 done = veth_xdp_rcv(rq, budget, &bq, &stats);
976
977 if (done < budget && napi_complete_done(napi, done)) {
978
979 smp_store_mb(rq->rx_notify_masked, false);
980 if (unlikely(!__ptr_ring_empty(&rq->xdp_ring))) {
981 if (napi_schedule_prep(&rq->xdp_napi)) {
982 WRITE_ONCE(rq->rx_notify_masked, true);
983 __napi_schedule(&rq->xdp_napi);
984 }
985 }
986 }
987
988 if (stats.xdp_tx > 0)
989 veth_xdp_flush(rq, &bq);
990 if (stats.xdp_redirect > 0)
991 xdp_do_flush();
992 xdp_clear_return_frame_no_direct();
993
994 return done;
995}
996
997static int __veth_napi_enable_range(struct net_device *dev, int start, int end)
998{
999 struct veth_priv *priv = netdev_priv(dev);
1000 int err, i;
1001
1002 for (i = start; i < end; i++) {
1003 struct veth_rq *rq = &priv->rq[i];
1004
1005 err = ptr_ring_init(&rq->xdp_ring, VETH_RING_SIZE, GFP_KERNEL);
1006 if (err)
1007 goto err_xdp_ring;
1008 }
1009
1010 for (i = start; i < end; i++) {
1011 struct veth_rq *rq = &priv->rq[i];
1012
1013 napi_enable(&rq->xdp_napi);
1014 rcu_assign_pointer(priv->rq[i].napi, &priv->rq[i].xdp_napi);
1015 }
1016
1017 return 0;
1018
1019err_xdp_ring:
1020 for (i--; i >= start; i--)
1021 ptr_ring_cleanup(&priv->rq[i].xdp_ring, veth_ptr_free);
1022
1023 return err;
1024}
1025
1026static int __veth_napi_enable(struct net_device *dev)
1027{
1028 return __veth_napi_enable_range(dev, 0, dev->real_num_rx_queues);
1029}
1030
1031static void veth_napi_del_range(struct net_device *dev, int start, int end)
1032{
1033 struct veth_priv *priv = netdev_priv(dev);
1034 int i;
1035
1036 for (i = start; i < end; i++) {
1037 struct veth_rq *rq = &priv->rq[i];
1038
1039 rcu_assign_pointer(priv->rq[i].napi, NULL);
1040 napi_disable(&rq->xdp_napi);
1041 __netif_napi_del(&rq->xdp_napi);
1042 }
1043 synchronize_net();
1044
1045 for (i = start; i < end; i++) {
1046 struct veth_rq *rq = &priv->rq[i];
1047
1048 rq->rx_notify_masked = false;
1049 ptr_ring_cleanup(&rq->xdp_ring, veth_ptr_free);
1050 }
1051}
1052
1053static void veth_napi_del(struct net_device *dev)
1054{
1055 veth_napi_del_range(dev, 0, dev->real_num_rx_queues);
1056}
1057
1058static bool veth_gro_requested(const struct net_device *dev)
1059{
1060 return !!(dev->wanted_features & NETIF_F_GRO);
1061}
1062
1063static int veth_enable_xdp_range(struct net_device *dev, int start, int end,
1064 bool napi_already_on)
1065{
1066 struct veth_priv *priv = netdev_priv(dev);
1067 int err, i;
1068
1069 for (i = start; i < end; i++) {
1070 struct veth_rq *rq = &priv->rq[i];
1071
1072 if (!napi_already_on)
1073 netif_napi_add(dev, &rq->xdp_napi, veth_poll, NAPI_POLL_WEIGHT);
1074 err = xdp_rxq_info_reg(&rq->xdp_rxq, dev, i, rq->xdp_napi.napi_id);
1075 if (err < 0)
1076 goto err_rxq_reg;
1077
1078 err = xdp_rxq_info_reg_mem_model(&rq->xdp_rxq,
1079 MEM_TYPE_PAGE_SHARED,
1080 NULL);
1081 if (err < 0)
1082 goto err_reg_mem;
1083
1084
1085 rq->xdp_mem = rq->xdp_rxq.mem;
1086 }
1087 return 0;
1088
1089err_reg_mem:
1090 xdp_rxq_info_unreg(&priv->rq[i].xdp_rxq);
1091err_rxq_reg:
1092 for (i--; i >= start; i--) {
1093 struct veth_rq *rq = &priv->rq[i];
1094
1095 xdp_rxq_info_unreg(&rq->xdp_rxq);
1096 if (!napi_already_on)
1097 netif_napi_del(&rq->xdp_napi);
1098 }
1099
1100 return err;
1101}
1102
1103static void veth_disable_xdp_range(struct net_device *dev, int start, int end,
1104 bool delete_napi)
1105{
1106 struct veth_priv *priv = netdev_priv(dev);
1107 int i;
1108
1109 for (i = start; i < end; i++) {
1110 struct veth_rq *rq = &priv->rq[i];
1111
1112 rq->xdp_rxq.mem = rq->xdp_mem;
1113 xdp_rxq_info_unreg(&rq->xdp_rxq);
1114
1115 if (delete_napi)
1116 netif_napi_del(&rq->xdp_napi);
1117 }
1118}
1119
1120static int veth_enable_xdp(struct net_device *dev)
1121{
1122 bool napi_already_on = veth_gro_requested(dev) && (dev->flags & IFF_UP);
1123 struct veth_priv *priv = netdev_priv(dev);
1124 int err, i;
1125
1126 if (!xdp_rxq_info_is_reg(&priv->rq[0].xdp_rxq)) {
1127 err = veth_enable_xdp_range(dev, 0, dev->real_num_rx_queues, napi_already_on);
1128 if (err)
1129 return err;
1130
1131 if (!napi_already_on) {
1132 err = __veth_napi_enable(dev);
1133 if (err) {
1134 veth_disable_xdp_range(dev, 0, dev->real_num_rx_queues, true);
1135 return err;
1136 }
1137
1138 if (!veth_gro_requested(dev)) {
1139
1140
1141
1142 dev->features |= NETIF_F_GRO;
1143 netdev_features_change(dev);
1144 }
1145 }
1146 }
1147
1148 for (i = 0; i < dev->real_num_rx_queues; i++) {
1149 rcu_assign_pointer(priv->rq[i].xdp_prog, priv->_xdp_prog);
1150 rcu_assign_pointer(priv->rq[i].napi, &priv->rq[i].xdp_napi);
1151 }
1152
1153 return 0;
1154}
1155
1156static void veth_disable_xdp(struct net_device *dev)
1157{
1158 struct veth_priv *priv = netdev_priv(dev);
1159 int i;
1160
1161 for (i = 0; i < dev->real_num_rx_queues; i++)
1162 rcu_assign_pointer(priv->rq[i].xdp_prog, NULL);
1163
1164 if (!netif_running(dev) || !veth_gro_requested(dev)) {
1165 veth_napi_del(dev);
1166
1167
1168
1169
1170 if (!veth_gro_requested(dev) && netif_running(dev)) {
1171 dev->features &= ~NETIF_F_GRO;
1172 netdev_features_change(dev);
1173 }
1174 }
1175
1176 veth_disable_xdp_range(dev, 0, dev->real_num_rx_queues, false);
1177}
1178
1179static int veth_napi_enable_range(struct net_device *dev, int start, int end)
1180{
1181 struct veth_priv *priv = netdev_priv(dev);
1182 int err, i;
1183
1184 for (i = start; i < end; i++) {
1185 struct veth_rq *rq = &priv->rq[i];
1186
1187 netif_napi_add(dev, &rq->xdp_napi, veth_poll, NAPI_POLL_WEIGHT);
1188 }
1189
1190 err = __veth_napi_enable_range(dev, start, end);
1191 if (err) {
1192 for (i = start; i < end; i++) {
1193 struct veth_rq *rq = &priv->rq[i];
1194
1195 netif_napi_del(&rq->xdp_napi);
1196 }
1197 return err;
1198 }
1199 return err;
1200}
1201
1202static int veth_napi_enable(struct net_device *dev)
1203{
1204 return veth_napi_enable_range(dev, 0, dev->real_num_rx_queues);
1205}
1206
1207static void veth_disable_range_safe(struct net_device *dev, int start, int end)
1208{
1209 struct veth_priv *priv = netdev_priv(dev);
1210
1211 if (start >= end)
1212 return;
1213
1214 if (priv->_xdp_prog) {
1215 veth_napi_del_range(dev, start, end);
1216 veth_disable_xdp_range(dev, start, end, false);
1217 } else if (veth_gro_requested(dev)) {
1218 veth_napi_del_range(dev, start, end);
1219 }
1220}
1221
1222static int veth_enable_range_safe(struct net_device *dev, int start, int end)
1223{
1224 struct veth_priv *priv = netdev_priv(dev);
1225 int err;
1226
1227 if (start >= end)
1228 return 0;
1229
1230 if (priv->_xdp_prog) {
1231
1232
1233
1234 err = veth_enable_xdp_range(dev, start, end, false);
1235 if (err)
1236 return err;
1237
1238 err = __veth_napi_enable_range(dev, start, end);
1239 if (err) {
1240
1241 veth_disable_xdp_range(dev, start, end, true);
1242 return err;
1243 }
1244 } else if (veth_gro_requested(dev)) {
1245 return veth_napi_enable_range(dev, start, end);
1246 }
1247 return 0;
1248}
1249
1250static int veth_set_channels(struct net_device *dev,
1251 struct ethtool_channels *ch)
1252{
1253 struct veth_priv *priv = netdev_priv(dev);
1254 unsigned int old_rx_count, new_rx_count;
1255 struct veth_priv *peer_priv;
1256 struct net_device *peer;
1257 int err;
1258
1259
1260 if (!ch->rx_count || !ch->tx_count)
1261 return -EINVAL;
1262
1263
1264 peer = rtnl_dereference(priv->peer);
1265 peer_priv = peer ? netdev_priv(peer) : NULL;
1266 if (priv->_xdp_prog && peer && ch->rx_count < peer->real_num_tx_queues)
1267 return -EINVAL;
1268
1269 if (peer && peer_priv && peer_priv->_xdp_prog && ch->tx_count > peer->real_num_rx_queues)
1270 return -EINVAL;
1271
1272 old_rx_count = dev->real_num_rx_queues;
1273 new_rx_count = ch->rx_count;
1274 if (netif_running(dev)) {
1275
1276 netif_carrier_off(dev);
1277 if (peer)
1278 netif_carrier_off(peer);
1279
1280
1281 err = veth_enable_range_safe(dev, old_rx_count, new_rx_count);
1282 if (err)
1283 goto out;
1284 }
1285
1286 err = netif_set_real_num_rx_queues(dev, ch->rx_count);
1287 if (err)
1288 goto revert;
1289
1290 err = netif_set_real_num_tx_queues(dev, ch->tx_count);
1291 if (err) {
1292 int err2 = netif_set_real_num_rx_queues(dev, old_rx_count);
1293
1294
1295
1296
1297
1298
1299 if (err2)
1300 pr_warn("Can't restore rx queues config %d -> %d %d",
1301 new_rx_count, old_rx_count, err2);
1302 else
1303 goto revert;
1304 }
1305
1306out:
1307 if (netif_running(dev)) {
1308
1309
1310
1311 veth_disable_range_safe(dev, new_rx_count, old_rx_count);
1312 netif_carrier_on(dev);
1313 if (peer)
1314 netif_carrier_on(peer);
1315 }
1316 return err;
1317
1318revert:
1319 new_rx_count = old_rx_count;
1320 old_rx_count = ch->rx_count;
1321 goto out;
1322}
1323
1324static int veth_open(struct net_device *dev)
1325{
1326 struct veth_priv *priv = netdev_priv(dev);
1327 struct net_device *peer = rtnl_dereference(priv->peer);
1328 int err;
1329
1330 if (!peer)
1331 return -ENOTCONN;
1332
1333 if (priv->_xdp_prog) {
1334 err = veth_enable_xdp(dev);
1335 if (err)
1336 return err;
1337 } else if (veth_gro_requested(dev)) {
1338 err = veth_napi_enable(dev);
1339 if (err)
1340 return err;
1341 }
1342
1343 if (peer->flags & IFF_UP) {
1344 netif_carrier_on(dev);
1345 netif_carrier_on(peer);
1346 }
1347
1348 return 0;
1349}
1350
1351static int veth_close(struct net_device *dev)
1352{
1353 struct veth_priv *priv = netdev_priv(dev);
1354 struct net_device *peer = rtnl_dereference(priv->peer);
1355
1356 netif_carrier_off(dev);
1357 if (peer)
1358 netif_carrier_off(peer);
1359
1360 if (priv->_xdp_prog)
1361 veth_disable_xdp(dev);
1362 else if (veth_gro_requested(dev))
1363 veth_napi_del(dev);
1364
1365 return 0;
1366}
1367
1368static int is_valid_veth_mtu(int mtu)
1369{
1370 return mtu >= ETH_MIN_MTU && mtu <= ETH_MAX_MTU;
1371}
1372
1373static int veth_alloc_queues(struct net_device *dev)
1374{
1375 struct veth_priv *priv = netdev_priv(dev);
1376 int i;
1377
1378 priv->rq = kcalloc(dev->num_rx_queues, sizeof(*priv->rq), GFP_KERNEL);
1379 if (!priv->rq)
1380 return -ENOMEM;
1381
1382 for (i = 0; i < dev->num_rx_queues; i++) {
1383 priv->rq[i].dev = dev;
1384 u64_stats_init(&priv->rq[i].stats.syncp);
1385 }
1386
1387 return 0;
1388}
1389
1390static void veth_free_queues(struct net_device *dev)
1391{
1392 struct veth_priv *priv = netdev_priv(dev);
1393
1394 kfree(priv->rq);
1395}
1396
1397static int veth_dev_init(struct net_device *dev)
1398{
1399 int err;
1400
1401 dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
1402 if (!dev->lstats)
1403 return -ENOMEM;
1404
1405 err = veth_alloc_queues(dev);
1406 if (err) {
1407 free_percpu(dev->lstats);
1408 return err;
1409 }
1410
1411 return 0;
1412}
1413
1414static void veth_dev_free(struct net_device *dev)
1415{
1416 veth_free_queues(dev);
1417 free_percpu(dev->lstats);
1418}
1419
1420#ifdef CONFIG_NET_POLL_CONTROLLER
1421static void veth_poll_controller(struct net_device *dev)
1422{
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432}
1433#endif
1434
1435static int veth_get_iflink(const struct net_device *dev)
1436{
1437 struct veth_priv *priv = netdev_priv(dev);
1438 struct net_device *peer;
1439 int iflink;
1440
1441 rcu_read_lock();
1442 peer = rcu_dereference(priv->peer);
1443 iflink = peer ? peer->ifindex : 0;
1444 rcu_read_unlock();
1445
1446 return iflink;
1447}
1448
1449static netdev_features_t veth_fix_features(struct net_device *dev,
1450 netdev_features_t features)
1451{
1452 struct veth_priv *priv = netdev_priv(dev);
1453 struct net_device *peer;
1454
1455 peer = rtnl_dereference(priv->peer);
1456 if (peer) {
1457 struct veth_priv *peer_priv = netdev_priv(peer);
1458
1459 if (peer_priv->_xdp_prog)
1460 features &= ~NETIF_F_GSO_SOFTWARE;
1461 }
1462 if (priv->_xdp_prog)
1463 features |= NETIF_F_GRO;
1464
1465 return features;
1466}
1467
1468static int veth_set_features(struct net_device *dev,
1469 netdev_features_t features)
1470{
1471 netdev_features_t changed = features ^ dev->features;
1472 struct veth_priv *priv = netdev_priv(dev);
1473 int err;
1474
1475 if (!(changed & NETIF_F_GRO) || !(dev->flags & IFF_UP) || priv->_xdp_prog)
1476 return 0;
1477
1478 if (features & NETIF_F_GRO) {
1479 err = veth_napi_enable(dev);
1480 if (err)
1481 return err;
1482 } else {
1483 veth_napi_del(dev);
1484 }
1485 return 0;
1486}
1487
1488static void veth_set_rx_headroom(struct net_device *dev, int new_hr)
1489{
1490 struct veth_priv *peer_priv, *priv = netdev_priv(dev);
1491 struct net_device *peer;
1492
1493 if (new_hr < 0)
1494 new_hr = 0;
1495
1496 rcu_read_lock();
1497 peer = rcu_dereference(priv->peer);
1498 if (unlikely(!peer))
1499 goto out;
1500
1501 peer_priv = netdev_priv(peer);
1502 priv->requested_headroom = new_hr;
1503 new_hr = max(priv->requested_headroom, peer_priv->requested_headroom);
1504 dev->needed_headroom = new_hr;
1505 peer->needed_headroom = new_hr;
1506
1507out:
1508 rcu_read_unlock();
1509}
1510
1511static int veth_xdp_set(struct net_device *dev, struct bpf_prog *prog,
1512 struct netlink_ext_ack *extack)
1513{
1514 struct veth_priv *priv = netdev_priv(dev);
1515 struct bpf_prog *old_prog;
1516 struct net_device *peer;
1517 unsigned int max_mtu;
1518 int err;
1519
1520 old_prog = priv->_xdp_prog;
1521 priv->_xdp_prog = prog;
1522 peer = rtnl_dereference(priv->peer);
1523
1524 if (prog) {
1525 if (!peer) {
1526 NL_SET_ERR_MSG_MOD(extack, "Cannot set XDP when peer is detached");
1527 err = -ENOTCONN;
1528 goto err;
1529 }
1530
1531 max_mtu = SKB_WITH_OVERHEAD(PAGE_SIZE - VETH_XDP_HEADROOM) -
1532 peer->hard_header_len;
1533
1534
1535
1536 if (prog->aux->xdp_has_frags)
1537 max_mtu += PAGE_SIZE * MAX_SKB_FRAGS;
1538
1539 if (peer->mtu > max_mtu) {
1540 NL_SET_ERR_MSG_MOD(extack, "Peer MTU is too large to set XDP");
1541 err = -ERANGE;
1542 goto err;
1543 }
1544
1545 if (dev->real_num_rx_queues < peer->real_num_tx_queues) {
1546 NL_SET_ERR_MSG_MOD(extack, "XDP expects number of rx queues not less than peer tx queues");
1547 err = -ENOSPC;
1548 goto err;
1549 }
1550
1551 if (dev->flags & IFF_UP) {
1552 err = veth_enable_xdp(dev);
1553 if (err) {
1554 NL_SET_ERR_MSG_MOD(extack, "Setup for XDP failed");
1555 goto err;
1556 }
1557 }
1558
1559 if (!old_prog) {
1560 peer->hw_features &= ~NETIF_F_GSO_SOFTWARE;
1561 peer->max_mtu = max_mtu;
1562 }
1563 }
1564
1565 if (old_prog) {
1566 if (!prog) {
1567 if (dev->flags & IFF_UP)
1568 veth_disable_xdp(dev);
1569
1570 if (peer) {
1571 peer->hw_features |= NETIF_F_GSO_SOFTWARE;
1572 peer->max_mtu = ETH_MAX_MTU;
1573 }
1574 }
1575 bpf_prog_put(old_prog);
1576 }
1577
1578 if ((!!old_prog ^ !!prog) && peer)
1579 netdev_update_features(peer);
1580
1581 return 0;
1582err:
1583 priv->_xdp_prog = old_prog;
1584
1585 return err;
1586}
1587
1588static int veth_xdp(struct net_device *dev, struct netdev_bpf *xdp)
1589{
1590 switch (xdp->command) {
1591 case XDP_SETUP_PROG:
1592 return veth_xdp_set(dev, xdp->prog, xdp->extack);
1593 default:
1594 return -EINVAL;
1595 }
1596}
1597
1598static const struct net_device_ops veth_netdev_ops = {
1599 .ndo_init = veth_dev_init,
1600 .ndo_open = veth_open,
1601 .ndo_stop = veth_close,
1602 .ndo_start_xmit = veth_xmit,
1603 .ndo_get_stats64 = veth_get_stats64,
1604 .ndo_set_rx_mode = veth_set_multicast_list,
1605 .ndo_set_mac_address = eth_mac_addr,
1606#ifdef CONFIG_NET_POLL_CONTROLLER
1607 .ndo_poll_controller = veth_poll_controller,
1608#endif
1609 .ndo_get_iflink = veth_get_iflink,
1610 .ndo_fix_features = veth_fix_features,
1611 .ndo_set_features = veth_set_features,
1612 .ndo_features_check = passthru_features_check,
1613 .ndo_set_rx_headroom = veth_set_rx_headroom,
1614 .ndo_bpf = veth_xdp,
1615 .ndo_xdp_xmit = veth_ndo_xdp_xmit,
1616 .ndo_get_peer_dev = veth_peer_dev,
1617};
1618
1619#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HW_CSUM | \
1620 NETIF_F_RXCSUM | NETIF_F_SCTP_CRC | NETIF_F_HIGHDMA | \
1621 NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL | \
1622 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
1623 NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
1624
1625static void veth_setup(struct net_device *dev)
1626{
1627 ether_setup(dev);
1628
1629 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1630 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1631 dev->priv_flags |= IFF_NO_QUEUE;
1632 dev->priv_flags |= IFF_PHONY_HEADROOM;
1633
1634 dev->netdev_ops = &veth_netdev_ops;
1635 dev->ethtool_ops = &veth_ethtool_ops;
1636 dev->features |= NETIF_F_LLTX;
1637 dev->features |= VETH_FEATURES;
1638 dev->vlan_features = dev->features &
1639 ~(NETIF_F_HW_VLAN_CTAG_TX |
1640 NETIF_F_HW_VLAN_STAG_TX |
1641 NETIF_F_HW_VLAN_CTAG_RX |
1642 NETIF_F_HW_VLAN_STAG_RX);
1643 dev->needs_free_netdev = true;
1644 dev->priv_destructor = veth_dev_free;
1645 dev->max_mtu = ETH_MAX_MTU;
1646
1647 dev->hw_features = VETH_FEATURES;
1648 dev->hw_enc_features = VETH_FEATURES;
1649 dev->mpls_features = NETIF_F_HW_CSUM | NETIF_F_GSO_SOFTWARE;
1650}
1651
1652
1653
1654
1655
1656static int veth_validate(struct nlattr *tb[], struct nlattr *data[],
1657 struct netlink_ext_ack *extack)
1658{
1659 if (tb[IFLA_ADDRESS]) {
1660 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1661 return -EINVAL;
1662 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1663 return -EADDRNOTAVAIL;
1664 }
1665 if (tb[IFLA_MTU]) {
1666 if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
1667 return -EINVAL;
1668 }
1669 return 0;
1670}
1671
1672static struct rtnl_link_ops veth_link_ops;
1673
1674static void veth_disable_gro(struct net_device *dev)
1675{
1676 dev->features &= ~NETIF_F_GRO;
1677 dev->wanted_features &= ~NETIF_F_GRO;
1678 netdev_update_features(dev);
1679}
1680
1681static int veth_init_queues(struct net_device *dev, struct nlattr *tb[])
1682{
1683 int err;
1684
1685 if (!tb[IFLA_NUM_TX_QUEUES] && dev->num_tx_queues > 1) {
1686 err = netif_set_real_num_tx_queues(dev, 1);
1687 if (err)
1688 return err;
1689 }
1690 if (!tb[IFLA_NUM_RX_QUEUES] && dev->num_rx_queues > 1) {
1691 err = netif_set_real_num_rx_queues(dev, 1);
1692 if (err)
1693 return err;
1694 }
1695 return 0;
1696}
1697
1698static int veth_newlink(struct net *src_net, struct net_device *dev,
1699 struct nlattr *tb[], struct nlattr *data[],
1700 struct netlink_ext_ack *extack)
1701{
1702 int err;
1703 struct net_device *peer;
1704 struct veth_priv *priv;
1705 char ifname[IFNAMSIZ];
1706 struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
1707 unsigned char name_assign_type;
1708 struct ifinfomsg *ifmp;
1709 struct net *net;
1710
1711
1712
1713
1714 if (data != NULL && data[VETH_INFO_PEER] != NULL) {
1715 struct nlattr *nla_peer;
1716
1717 nla_peer = data[VETH_INFO_PEER];
1718 ifmp = nla_data(nla_peer);
1719 err = rtnl_nla_parse_ifla(peer_tb,
1720 nla_data(nla_peer) + sizeof(struct ifinfomsg),
1721 nla_len(nla_peer) - sizeof(struct ifinfomsg),
1722 NULL);
1723 if (err < 0)
1724 return err;
1725
1726 err = veth_validate(peer_tb, NULL, extack);
1727 if (err < 0)
1728 return err;
1729
1730 tbp = peer_tb;
1731 } else {
1732 ifmp = NULL;
1733 tbp = tb;
1734 }
1735
1736 if (ifmp && tbp[IFLA_IFNAME]) {
1737 nla_strscpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
1738 name_assign_type = NET_NAME_USER;
1739 } else {
1740 snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
1741 name_assign_type = NET_NAME_ENUM;
1742 }
1743
1744 net = rtnl_link_get_net(src_net, tbp);
1745 if (IS_ERR(net))
1746 return PTR_ERR(net);
1747
1748 peer = rtnl_create_link(net, ifname, name_assign_type,
1749 &veth_link_ops, tbp, extack);
1750 if (IS_ERR(peer)) {
1751 put_net(net);
1752 return PTR_ERR(peer);
1753 }
1754
1755 if (!ifmp || !tbp[IFLA_ADDRESS])
1756 eth_hw_addr_random(peer);
1757
1758 if (ifmp && (dev->ifindex != 0))
1759 peer->ifindex = ifmp->ifi_index;
1760
1761 netif_set_gso_max_size(peer, dev->gso_max_size);
1762 netif_set_gso_max_segs(peer, dev->gso_max_segs);
1763
1764 err = register_netdevice(peer);
1765 put_net(net);
1766 net = NULL;
1767 if (err < 0)
1768 goto err_register_peer;
1769
1770
1771
1772
1773 veth_disable_gro(peer);
1774 netif_carrier_off(peer);
1775
1776 err = rtnl_configure_link(peer, ifmp);
1777 if (err < 0)
1778 goto err_configure_peer;
1779
1780
1781
1782
1783
1784
1785
1786
1787 if (tb[IFLA_ADDRESS] == NULL)
1788 eth_hw_addr_random(dev);
1789
1790 if (tb[IFLA_IFNAME])
1791 nla_strscpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
1792 else
1793 snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
1794
1795 err = register_netdevice(dev);
1796 if (err < 0)
1797 goto err_register_dev;
1798
1799 netif_carrier_off(dev);
1800
1801
1802
1803
1804
1805 priv = netdev_priv(dev);
1806 rcu_assign_pointer(priv->peer, peer);
1807 err = veth_init_queues(dev, tb);
1808 if (err)
1809 goto err_queues;
1810
1811 priv = netdev_priv(peer);
1812 rcu_assign_pointer(priv->peer, dev);
1813 err = veth_init_queues(peer, tb);
1814 if (err)
1815 goto err_queues;
1816
1817 veth_disable_gro(dev);
1818 return 0;
1819
1820err_queues:
1821 unregister_netdevice(dev);
1822err_register_dev:
1823
1824err_configure_peer:
1825 unregister_netdevice(peer);
1826 return err;
1827
1828err_register_peer:
1829 free_netdev(peer);
1830 return err;
1831}
1832
1833static void veth_dellink(struct net_device *dev, struct list_head *head)
1834{
1835 struct veth_priv *priv;
1836 struct net_device *peer;
1837
1838 priv = netdev_priv(dev);
1839 peer = rtnl_dereference(priv->peer);
1840
1841
1842
1843
1844
1845 RCU_INIT_POINTER(priv->peer, NULL);
1846 unregister_netdevice_queue(dev, head);
1847
1848 if (peer) {
1849 priv = netdev_priv(peer);
1850 RCU_INIT_POINTER(priv->peer, NULL);
1851 unregister_netdevice_queue(peer, head);
1852 }
1853}
1854
1855static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
1856 [VETH_INFO_PEER] = { .len = sizeof(struct ifinfomsg) },
1857};
1858
1859static struct net *veth_get_link_net(const struct net_device *dev)
1860{
1861 struct veth_priv *priv = netdev_priv(dev);
1862 struct net_device *peer = rtnl_dereference(priv->peer);
1863
1864 return peer ? dev_net(peer) : dev_net(dev);
1865}
1866
1867static unsigned int veth_get_num_queues(void)
1868{
1869
1870 int queues = num_possible_cpus();
1871
1872 if (queues > 4096)
1873 queues = 4096;
1874 return queues;
1875}
1876
1877static struct rtnl_link_ops veth_link_ops = {
1878 .kind = DRV_NAME,
1879 .priv_size = sizeof(struct veth_priv),
1880 .setup = veth_setup,
1881 .validate = veth_validate,
1882 .newlink = veth_newlink,
1883 .dellink = veth_dellink,
1884 .policy = veth_policy,
1885 .maxtype = VETH_INFO_MAX,
1886 .get_link_net = veth_get_link_net,
1887 .get_num_tx_queues = veth_get_num_queues,
1888 .get_num_rx_queues = veth_get_num_queues,
1889};
1890
1891
1892
1893
1894
1895static __init int veth_init(void)
1896{
1897 return rtnl_link_register(&veth_link_ops);
1898}
1899
1900static __exit void veth_exit(void)
1901{
1902 rtnl_link_unregister(&veth_link_ops);
1903}
1904
1905module_init(veth_init);
1906module_exit(veth_exit);
1907
1908MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
1909MODULE_LICENSE("GPL v2");
1910MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1911
