aboutsummaryrefslogtreecommitdiffstats
path: root/src/plugins/af_packet/device.c
blob: fc6733fc446cbcfc55166bedb7766e83be1652df (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
/*
 *------------------------------------------------------------------
 * af_packet.c - linux kernel packet interface
 *
 * Copyright (c) 2016 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *------------------------------------------------------------------
 */

#include <linux/if_packet.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <net/if_arp.h>

#include <vlib/vlib.h>
#include <vlib/unix/unix.h>
#include <vnet/ip/ip.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/ip/ip4_packet.h>
#include <vnet/ip/ip6_packet.h>
#include <vnet/ip/ip_psh_cksum.h>
#include <vnet/tcp/tcp_packet.h>
#include <vnet/udp/udp_packet.h>

#include <af_packet/af_packet.h>
#include <vnet/devices/virtio/virtio_std.h>
#include <vnet/devices/netlink.h>

#define foreach_af_packet_tx_func_error               \
_(FRAME_NOT_READY, "tx frame not ready")              \
_(TXRING_EAGAIN,   "tx sendto temporary failure")     \
_(TXRING_FATAL,    "tx sendto fatal failure")         \
_(TXRING_OVERRUN,  "tx ring overrun")

typedef enum
{
#define _(f,s) AF_PACKET_TX_ERROR_##f,
  foreach_af_packet_tx_func_error
#undef _
    AF_PACKET_TX_N_ERROR,
} af_packet_tx_func_error_t;

static char *af_packet_tx_func_error_strings[] = {
#define _(n,s) s,
  foreach_af_packet_tx_func_error
#undef _
};

typedef struct
{
  u32 buffer_index;
  u32 hw_if_index;
  u16 queue_id;
  u8 is_v2;
  union
  {
    tpacket2_hdr_t tph2;
    tpacket3_hdr_t tph3;
  };
  vnet_virtio_net_hdr_t vnet_hdr;
  vlib_buffer_t buffer;
} af_packet_tx_trace_t;

#ifndef CLIB_MARCH_VARIANT
u8 *
format_af_packet_device_name (u8 * s, va_list * args)
{
  u32 i = va_arg (*args, u32);
  af_packet_main_t *apm = &af_packet_main;
  af_packet_if_t *apif = pool_elt_at_index (apm->interfaces, i);

  s = format (s, "host-%s", apif->host_if_name);
  return s;
}
#endif /* CLIB_MARCH_VARIANT */

static u8 *
format_af_packet_device (u8 * s, va_list * args)
{
  u32 dev_instance = va_arg (*args, u32);
  u32 indent = format_get_indent (s);
  int __clib_unused verbose = va_arg (*args, int);

  af_packet_main_t *apm = &af_packet_main;
  af_packet_if_t *apif = pool_elt_at_index (apm->interfaces, dev_instance);
  af_packet_queue_t *rx_queue = 0;
  af_packet_queue_t *tx_queue = 0;

  s = format (s, "Linux PACKET socket interface %s",
	      (apif->version == TPACKET_V2) ? "v2" : "v3");
  s = format (s, "\n%UFEATURES:", format_white_space, indent);
  if (apif->is_qdisc_bypass_enabled)
    s = format (s, "\n%Uqdisc-bpass-enabled", format_white_space, indent + 2);
  if (apif->is_cksum_gso_enabled)
    s = format (s, "\n%Ucksum-gso-enabled", format_white_space, indent + 2);
  if (apif->is_fanout_enabled)
    s = format (s, "\n%Ufanout-enabled", format_white_space, indent + 2);

  vec_foreach (rx_queue, apif->rx_queues)
    {
      u32 rx_block_size = rx_queue->rx_req->req.tp_block_size;
      u32 rx_frame_size = rx_queue->rx_req->req.tp_frame_size;
      u32 rx_frame_nr = rx_queue->rx_req->req.tp_frame_nr;
      u32 rx_block_nr = rx_queue->rx_req->req.tp_block_nr;

      s = format (s, "\n%URX Queue %u:", format_white_space, indent,
		  rx_queue->queue_id);
      s = format (s, "\n%Ublock size:%d nr:%d  frame size:%d nr:%d",
		  format_white_space, indent + 2, rx_block_size, rx_block_nr,
		  rx_frame_size, rx_frame_nr);
      if (apif->version == TPACKET_V2)
	s = format (s, " next frame:%d", rx_queue->next_rx_frame);
      else
	s = format (s, " next block:%d", rx_queue->next_rx_block);
      if (rx_queue->is_rx_pending)
	{
	  s = format (
	    s, "\n%UPending Request: num-rx-pkts:%d next-frame-offset:%d",
	    format_white_space, indent + 2, rx_queue->num_rx_pkts,
	    rx_queue->rx_frame_offset);
	}
    }

  vec_foreach (tx_queue, apif->tx_queues)
    {
      clib_spinlock_lock (&tx_queue->lockp);
      u32 tx_block_sz = tx_queue->tx_req->req.tp_block_size;
      u32 tx_frame_sz = tx_queue->tx_req->req.tp_frame_size;
      u32 tx_frame_nr = tx_queue->tx_req->req.tp_frame_nr;
      u32 tx_block_nr = tx_queue->tx_req->req.tp_block_nr;
      int block = 0;
      int n_send_req = 0, n_avail = 0, n_sending = 0, n_tot = 0, n_wrong = 0;
      u8 *tx_block_start = tx_queue->tx_ring[block];
      u32 tx_frame = tx_queue->next_tx_frame;
      tpacket3_hdr_t *tph3;
      tpacket2_hdr_t *tph2;

      s = format (s, "\n%UTX Queue %u:", format_white_space, indent,
		  tx_queue->queue_id);
      s = format (s, "\n%Ublock size:%d nr:%d  frame size:%d nr:%d",
		  format_white_space, indent + 2, tx_block_sz, tx_block_nr,
		  tx_frame_sz, tx_frame_nr);
      s = format (s, " next frame:%d", tx_queue->next_tx_frame);
      if (apif->version & TPACKET_V3)
	do
	  {
	    tph3 =
	      (tpacket3_hdr_t *) (tx_block_start + tx_frame * tx_frame_sz);
	    tx_frame = (tx_frame + 1) % tx_frame_nr;
	    if (tph3->tp_status == 0)
	      n_avail++;
	    else if (tph3->tp_status & TP_STATUS_SEND_REQUEST)
	      n_send_req++;
	    else if (tph3->tp_status & TP_STATUS_SENDING)
	      n_sending++;
	    else
	      n_wrong++;
	    n_tot++;
	  }
	while (tx_frame != tx_queue->next_tx_frame);
      else
	do
	  {
	    tph2 =
	      (tpacket2_hdr_t *) (tx_block_start + tx_frame * tx_frame_sz);
	    tx_frame = (tx_frame + 1) % tx_frame_nr;
	    if (tph2->tp_status == 0)
	      n_avail++;
	    else if (tph2->tp_status & TP_STATUS_SEND_REQUEST)
	      n_send_req++;
	    else if (tph2->tp_status & TP_STATUS_SENDING)
	      n_sending++;
	    else
	      n_wrong++;
	    n_tot++;
	  }
	while (tx_frame != tx_queue->next_tx_frame);
      s =
	format (s, "\n%Uavailable:%d request:%d sending:%d wrong:%d total:%d",
		format_white_space, indent + 2, n_avail, n_send_req, n_sending,
		n_wrong, n_tot);
      clib_spinlock_unlock (&tx_queue->lockp);
    }
  return s;
}

static u8 *
format_af_packet_tx_trace (u8 *s, va_list *va)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
  af_packet_tx_trace_t *t = va_arg (*va, af_packet_tx_trace_t *);
  u32 indent = format_get_indent (s);

  s = format (s, "af_packet: hw_if_index %u tx-queue %u", t->hw_if_index,
	      t->queue_id);

  if (t->is_v2)
    {
      s = format (
	s,
	"\n%Utpacket2_hdr:\n%Ustatus 0x%x len %u snaplen %u mac %u net %u"
	"\n%Usec 0x%x nsec 0x%x vlan %U"
#ifdef TP_STATUS_VLAN_TPID_VALID
	" vlan_tpid %u"
#endif
	,
	format_white_space, indent + 2, format_white_space, indent + 4,
	t->tph2.tp_status, t->tph2.tp_len, t->tph2.tp_snaplen, t->tph2.tp_mac,
	t->tph2.tp_net, format_white_space, indent + 4, t->tph2.tp_sec,
	t->tph2.tp_nsec, format_ethernet_vlan_tci, t->tph2.tp_vlan_tci
#ifdef TP_STATUS_VLAN_TPID_VALID
	,
	t->tph2.tp_vlan_tpid
#endif
      );
    }
  else
    {
      s = format (
	s,
	"\n%Utpacket3_hdr:\n%Ustatus 0x%x len %u snaplen %u mac %u net %u"
	"\n%Usec 0x%x nsec 0x%x vlan %U"
#ifdef TP_STATUS_VLAN_TPID_VALID
	" vlan_tpid %u"
#endif
	,
	format_white_space, indent + 2, format_white_space, indent + 4,
	t->tph3.tp_status, t->tph3.tp_len, t->tph3.tp_snaplen, t->tph3.tp_mac,
	t->tph3.tp_net, format_white_space, indent + 4, t->tph3.tp_sec,
	t->tph3.tp_nsec, format_ethernet_vlan_tci, t->tph3.hv1.tp_vlan_tci
#ifdef TP_STATUS_VLAN_TPID_VALID
	,
	t->tph3.hv1.tp_vlan_tpid
#endif
      );
    }
  s = format (s,
	      "\n%Uvnet-hdr:\n%Uflags 0x%02x gso_type 0x%02x hdr_len %u"
	      "\n%Ugso_size %u csum_start %u csum_offset %u",
	      format_white_space, indent + 2, format_white_space, indent + 4,
	      t->vnet_hdr.flags, t->vnet_hdr.gso_type, t->vnet_hdr.hdr_len,
	      format_white_space, indent + 4, t->vnet_hdr.gso_size,
	      t->vnet_hdr.csum_start, t->vnet_hdr.csum_offset);

  s = format (s, "\n%Ubuffer 0x%x:\n%U%U", format_white_space, indent + 2,
	      t->buffer_index, format_white_space, indent + 4,
	      format_vnet_buffer_no_chain, &t->buffer);
  s = format (s, "\n%U%U", format_white_space, indent + 2,
	      format_ethernet_header_with_length, t->buffer.pre_data,
	      sizeof (t->buffer.pre_data));
  return s;
}

static void
af_packet_tx_trace (vlib_main_t *vm, vlib_node_runtime_t *node,
		    vlib_buffer_t *b0, u32 bi, void *tph,
		    vnet_virtio_net_hdr_t *vnet_hdr, u32 hw_if_index,
		    u16 queue_id, u8 is_v2)
{
  af_packet_tx_trace_t *t;
  t = vlib_add_trace (vm, node, b0, sizeof (t[0]));
  t->hw_if_index = hw_if_index;
  t->queue_id = queue_id;
  t->buffer_index = bi;
  t->is_v2 = is_v2;

  if (is_v2)
    clib_memcpy_fast (&t->tph2, (tpacket2_hdr_t *) tph,
		      sizeof (tpacket2_hdr_t));
  else
    clib_memcpy_fast (&t->tph3, (tpacket3_hdr_t *) tph,
		      sizeof (tpacket3_hdr_t));
  clib_memcpy_fast (&t->vnet_hdr, vnet_hdr, sizeof (*vnet_hdr));
  clib_memcpy_fast (&t->buffer, b0, sizeof (*b0) - sizeof (b0->pre_data));
  clib_memcpy_fast (t->buffer.pre_data, vlib_buffer_get_current (b0),
		    sizeof (t->buffer.pre_data));
}

static_always_inline void
fill_gso_offload (vlib_buffer_t *b0, vnet_virtio_net_hdr_t *vnet_hdr)
{
  vnet_buffer_oflags_t oflags = vnet_buffer (b0)->oflags;
  i16 l4_hdr_offset = vnet_buffer (b0)->l4_hdr_offset - b0->current_data;
  if (b0->flags & VNET_BUFFER_F_IS_IP4)
    {
      ip4_header_t *ip4;
      vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
      vnet_hdr->gso_size = vnet_buffer2 (b0)->gso_size;
      vnet_hdr->hdr_len = l4_hdr_offset + vnet_buffer2 (b0)->gso_l4_hdr_sz;
      vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
      vnet_hdr->csum_start = l4_hdr_offset; // 0x22;
      vnet_hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
      ip4 = (ip4_header_t *) (b0->data + vnet_buffer (b0)->l3_hdr_offset);
      if (oflags & VNET_BUFFER_OFFLOAD_F_IP_CKSUM)
	ip4->checksum = ip4_header_checksum (ip4);
      tcp_header_t *tcp =
	(tcp_header_t *) (b0->data + vnet_buffer (b0)->l4_hdr_offset);
      tcp->checksum = ip4_pseudo_header_cksum (ip4);
    }
  else if (b0->flags & VNET_BUFFER_F_IS_IP6)
    {
      ip6_header_t *ip6;
      vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
      vnet_hdr->gso_size = vnet_buffer2 (b0)->gso_size;
      vnet_hdr->hdr_len = l4_hdr_offset + vnet_buffer2 (b0)->gso_l4_hdr_sz;
      vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
      vnet_hdr->csum_start = l4_hdr_offset; // 0x36;
      vnet_hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
      ip6 = (ip6_header_t *) (b0->data + vnet_buffer (b0)->l3_hdr_offset);
      tcp_header_t *tcp =
	(tcp_header_t *) (b0->data + vnet_buffer (b0)->l4_hdr_offset);
      tcp->checksum = ip6_pseudo_header_cksum (ip6);
    }
}

static_always_inline void
fill_cksum_offload (vlib_buffer_t *b0, vnet_virtio_net_hdr_t *vnet_hdr)
{
  vnet_buffer_oflags_t oflags = vnet_buffer (b0)->oflags;
  i16 l4_hdr_offset = vnet_buffer (b0)->l4_hdr_offset - b0->current_data;
  if (b0->flags & VNET_BUFFER_F_IS_IP4)
    {
      ip4_header_t *ip4;
      ip4 = (ip4_header_t *) (b0->data + vnet_buffer (b0)->l3_hdr_offset);
      if (oflags & VNET_BUFFER_OFFLOAD_F_IP_CKSUM)
	ip4->checksum = ip4_header_checksum (ip4);
      vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
      vnet_hdr->csum_start = l4_hdr_offset;
      if (oflags & VNET_BUFFER_OFFLOAD_F_TCP_CKSUM)
	{
	  tcp_header_t *tcp =
	    (tcp_header_t *) (b0->data + vnet_buffer (b0)->l4_hdr_offset);
	  tcp->checksum = ip4_pseudo_header_cksum (ip4);
	  vnet_hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
	  vnet_hdr->hdr_len = l4_hdr_offset + tcp_header_bytes (tcp);
	}
      else if (oflags & VNET_BUFFER_OFFLOAD_F_UDP_CKSUM)
	{
	  udp_header_t *udp =
	    (udp_header_t *) (b0->data + vnet_buffer (b0)->l4_hdr_offset);
	  udp->checksum = ip4_pseudo_header_cksum (ip4);
	  vnet_hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
	  vnet_hdr->hdr_len = l4_hdr_offset + sizeof (udp_header_t);
	}
    }
  else if (b0->flags & VNET_BUFFER_F_IS_IP6)
    {
      ip6_header_t *ip6;
      vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
      vnet_hdr->csum_start = l4_hdr_offset;
      ip6 = (ip6_header_t *) (b0->data + vnet_buffer (b0)->l3_hdr_offset);
      if (oflags & VNET_BUFFER_OFFLOAD_F_TCP_CKSUM)
	{
	  tcp_header_t *tcp =
	    (tcp_header_t *) (b0->data + vnet_buffer (b0)->l4_hdr_offset);
	  tcp->checksum = ip6_pseudo_header_cksum (ip6);
	  vnet_hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
	  vnet_hdr->hdr_len = l4_hdr_offset + tcp_header_bytes (tcp);
	}
      else if (oflags & VNET_BUFFER_OFFLOAD_F_UDP_CKSUM)
	{
	  udp_header_t *udp =
	    (udp_header_t *) (b0->data + vnet_buffer (b0)->l4_hdr_offset);
	  udp->checksum = ip6_pseudo_header_cksum (ip6);
	  vnet_hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
	  vnet_hdr->hdr_len = l4_hdr_offset + sizeof (udp_header_t);
	}
    }
}

VNET_DEVICE_CLASS_TX_FN (af_packet_device_class) (vlib_main_t * vm,
						  vlib_node_runtime_t * node,
						  vlib_frame_t * frame)
{
  af_packet_main_t *apm = &af_packet_main;
  vnet_hw_if_tx_frame_t *tf = vlib_frame_scalar_args (frame);
  u32 *buffers = vlib_frame_vector_args (frame);
  u32 n_left = frame->n_vectors;
  u32 n_sent = 0;
  vnet_interface_output_runtime_t *rd = (void *) node->runtime_data;
  af_packet_if_t *apif =
    pool_elt_at_index (apm->interfaces, rd->dev_instance);
  u16 queue_id = tf->queue_id;
  af_packet_queue_t *tx_queue = vec_elt_at_index (apif->tx_queues, queue_id);
  u32 block = 0, frame_size = 0, frame_num = 0, tx_frame = 0;
  u8 *block_start = 0;
  tpacket3_hdr_t *tph3 = 0;
  tpacket2_hdr_t *tph2 = 0;
  u32 frame_not_ready = 0;
  u8 is_cksum_gso_enabled = (apif->is_cksum_gso_enabled == 1) ? 1 : 0;
  u32 tpacket_align = 0;
  u8 is_v2 = (apif->version == TPACKET_V2) ? 1 : 0;

  if (tf->shared_queue)
    clib_spinlock_lock (&tx_queue->lockp);

  frame_size = tx_queue->tx_req->req.tp_frame_size;
  frame_num = tx_queue->tx_req->req.tp_frame_nr;
  block_start = tx_queue->tx_ring[block];
  tx_frame = tx_queue->next_tx_frame;
  if (is_v2)
    {
      tpacket_align = TPACKET_ALIGN (sizeof (tpacket2_hdr_t));
      while (n_left)
	{
	  u32 len;
	  vnet_virtio_net_hdr_t *vnet_hdr = 0;
	  u32 offset = 0;
	  vlib_buffer_t *b0 = 0, *b0_first = 0;
	  u32 bi, bi_first;

	  bi = bi_first = buffers[0];
	  n_left--;
	  buffers++;

	  tph2 = (tpacket2_hdr_t *) (block_start + tx_frame * frame_size);
	  if (PREDICT_FALSE (tph2->tp_status &
			     (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING)))
	    {
	      frame_not_ready++;
	      goto nextv2;
	    }

	  b0_first = b0 = vlib_get_buffer (vm, bi);

	  if (PREDICT_TRUE (is_cksum_gso_enabled))
	    {
	      vnet_hdr =
		(vnet_virtio_net_hdr_t *) ((u8 *) tph2 + tpacket_align);

	      clib_memset_u8 (vnet_hdr, 0, sizeof (vnet_virtio_net_hdr_t));
	      offset = sizeof (vnet_virtio_net_hdr_t);

	      if (b0->flags & VNET_BUFFER_F_GSO)
		fill_gso_offload (b0, vnet_hdr);
	      else if (b0->flags & VNET_BUFFER_F_OFFLOAD)
		fill_cksum_offload (b0, vnet_hdr);
	    }

	  len = b0->current_length;
	  clib_memcpy_fast ((u8 *) tph2 + tpacket_align + offset,
			    vlib_buffer_get_current (b0), len);
	  offset += len;

	  while (b0->flags & VLIB_BUFFER_NEXT_PRESENT)
	    {
	      b0 = vlib_get_buffer (vm, b0->next_buffer);
	      len = b0->current_length;
	      clib_memcpy_fast ((u8 *) tph2 + tpacket_align + offset,
				vlib_buffer_get_current (b0), len);
	      offset += len;
	    }

	  tph2->tp_len = tph2->tp_snaplen = offset;
	  tph2->tp_status = TP_STATUS_SEND_REQUEST;
	  n_sent++;

	  if (PREDICT_FALSE (b0_first->flags & VLIB_BUFFER_IS_TRACED))
	    {
	      if (PREDICT_TRUE (is_cksum_gso_enabled))
		af_packet_tx_trace (vm, node, b0_first, bi_first, tph2,
				    vnet_hdr, apif->hw_if_index, queue_id, 1);
	      else
		{
		  vnet_virtio_net_hdr_t vnet_hdr2 = {};
		  af_packet_tx_trace (vm, node, b0_first, bi_first, tph2,
				      &vnet_hdr2, apif->hw_if_index, queue_id,
				      1);
		}
	    }
	  tx_frame = (tx_frame + 1) % frame_num;

	nextv2:
	  /* check if we've exhausted the ring */
	  if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
	    break;
	}
    }
  else
    {
      tpacket_align = TPACKET_ALIGN (sizeof (tpacket3_hdr_t));

      while (n_left)
	{
	  u32 len;
	  vnet_virtio_net_hdr_t *vnet_hdr = 0;
	  u32 offset = 0;
	  vlib_buffer_t *b0 = 0, *b0_first = 0;
	  u32 bi, bi_first;

	  bi = bi_first = buffers[0];
	  n_left--;
	  buffers++;

	  tph3 = (tpacket3_hdr_t *) (block_start + tx_frame * frame_size);
	  if (PREDICT_FALSE (tph3->tp_status &
			     (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING)))
	    {
	      frame_not_ready++;
	      goto nextv3;
	    }

	  b0_first = b0 = vlib_get_buffer (vm, bi);

	  if (PREDICT_TRUE (is_cksum_gso_enabled))
	    {
	      vnet_hdr =
		(vnet_virtio_net_hdr_t *) ((u8 *) tph3 + tpacket_align);

	      clib_memset_u8 (vnet_hdr, 0, sizeof (vnet_virtio_net_hdr_t));
	      offset = sizeof (vnet_virtio_net_hdr_t);

	      if (b0->flags & VNET_BUFFER_F_GSO)
		fill_gso_offload (b0, vnet_hdr);
	      else if (b0->flags & VNET_BUFFER_F_OFFLOAD)
		fill_cksum_offload (b0, vnet_hdr);
	    }

	  len = b0->current_length;
	  clib_memcpy_fast ((u8 *) tph3 + tpacket_align + offset,
			    vlib_buffer_get_current (b0), len);
	  offset += len;

	  while (b0->flags & VLIB_BUFFER_NEXT_PRESENT)
	    {
	      b0 = vlib_get_buffer (vm, b0->next_buffer);
	      len = b0->current_length;
	      clib_memcpy_fast ((u8 *) tph3 + tpacket_align + offset,
				vlib_buffer_get_current (b0), len);
	      offset += len;
	    }

	  tph3->tp_len = tph3->tp_snaplen = offset;
	  tph3->tp_status = TP_STATUS_SEND_REQUEST;
	  n_sent++;

	  if (PREDICT_FALSE (b0_first->flags & VLIB_BUFFER_IS_TRACED))
	    {
	      if (PREDICT_TRUE (is_cksum_gso_enabled))
		af_packet_tx_trace (vm, node, b0_first, bi_first, tph3,
				    vnet_hdr, apif->hw_if_index, queue_id, 0);
	      else
		{
		  vnet_virtio_net_hdr_t vnet_hdr2 = {};
		  af_packet_tx_trace (vm, node, b0_first, bi_first, tph3,
				      &vnet_hdr2, apif->hw_if_index, queue_id,
				      0);
		}
	    }
	  tx_frame = (tx_frame + 1) % frame_num;

	nextv3:
	  /* check if we've exhausted the ring */
	  if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
	    break;
	}
    }
  CLIB_MEMORY_BARRIER ();

  if (PREDICT_TRUE (n_sent || tx_queue->is_tx_pending))
    {
      tx_queue->next_tx_frame = tx_frame;
      tx_queue->is_tx_pending = 0;

      if (PREDICT_FALSE (
	    sendto (tx_queue->fd, NULL, 0, MSG_DONTWAIT, NULL, 0) == -1))
	{
	  /* Uh-oh, drop & move on, but count whether it was fatal or not.
	   * Note that we have no reliable way to properly determine the
	   * disposition of the packets we just enqueued for delivery.
	   */
	  uword counter;

	  if (unix_error_is_fatal (errno))
	    {
	      counter = AF_PACKET_TX_ERROR_TXRING_FATAL;
	    }
	  else
	    {
	      counter = AF_PACKET_TX_ERROR_TXRING_EAGAIN;
	      /* non-fatal error: kick again next time
	       * note that you could still end up in a deadlock: if you do not
	       * try to send new packets (ie reschedule this tx node), eg.
	       * because your peer is waiting for the unsent packets to reply
	       * to you but your waiting for its reply etc., you are not going
	       * to kick again, and everybody is waiting for the other to talk
	       * 1st... */
	      tx_queue->is_tx_pending = 1;
	    }

	  vlib_error_count (vm, node->node_index, counter, 1);
	}
    }

  if (tf->shared_queue)
    clib_spinlock_unlock (&tx_queue->lockp);

  if (PREDICT_FALSE (frame_not_ready))
    vlib_error_count (vm, node->node_index,
		      AF_PACKET_TX_ERROR_FRAME_NOT_READY, frame_not_ready);

  if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
    vlib_error_count (vm, node->node_index, AF_PACKET_TX_ERROR_TXRING_OVERRUN,
		      n_left);

  vlib_buffer_free (vm, vlib_frame_vector_args (frame), frame->n_vectors);
  return frame->n_vectors;
}

static void
af_packet_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
				   u32 node_index)
{
  af_packet_main_t *apm = &af_packet_main;
  vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
  af_packet_if_t *apif =
    pool_elt_at_index (apm->interfaces, hw->dev_instance);

  /* Shut off redirection */
  if (node_index == ~0)
    {
      apif->per_interface_next_index = node_index;
      return;
    }

  apif->per_interface_next_index =
    vlib_node_add_next (vlib_get_main (), af_packet_input_node.index,
			node_index);
}

static void
af_packet_clear_hw_interface_counters (u32 instance)
{
  /* Nothing for now */
}

static clib_error_t *
af_packet_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index,
				   u32 flags)
{
  af_packet_main_t *apm = &af_packet_main;
  vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
  af_packet_if_t *apif =
    pool_elt_at_index (apm->interfaces, hw->dev_instance);
  u32 hw_flags;

  if (apif->host_if_index < 0)
    return 0; /* no error */

  apif->is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;

  if (apif->is_admin_up)
    {
      hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP;
      vnet_netlink_set_link_state (apif->host_if_index, 1);
    }
  else
    {
      hw_flags = 0;
      vnet_netlink_set_link_state (apif->host_if_index, 0);
    }

  vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);

  return 0;			/* no error */
}

static clib_error_t *
af_packet_subif_add_del_function (vnet_main_t * vnm,
				  u32 hw_if_index,
				  struct vnet_sw_interface_t *st, int is_add)
{
  /* Nothing for now */
  return 0;
}

static clib_error_t *af_packet_set_mac_address_function
  (struct vnet_hw_interface_t *hi, const u8 * old_address, const u8 * address)
{
  af_packet_main_t *apm = &af_packet_main;
  af_packet_if_t *apif =
    pool_elt_at_index (apm->interfaces, hi->dev_instance);
  int rv, fd;
  struct ifreq ifr;

  if (apif->mode == AF_PACKET_IF_MODE_IP)
    {
      vlib_log_warn (apm->log_class, "af_packet_%s interface is in IP mode",
		     apif->host_if_name);
      return clib_error_return (0,
				" MAC update failed, interface is in IP mode");
    }

  fd = socket (AF_UNIX, SOCK_DGRAM, 0);
  if (0 > fd)
    {
      vlib_log_warn (apm->log_class, "af_packet_%s could not open socket",
		     apif->host_if_name);
      return 0;
    }

  /* if interface is a bridge ignore */
  if (apif->host_if_index < 0)
    goto error;			/* no error */

  /* use host_if_index in case host name has changed */
  ifr.ifr_ifindex = apif->host_if_index;
  if ((rv = ioctl (fd, SIOCGIFNAME, &ifr)) < 0)
    {
      vlib_log_warn
	(apm->log_class,
	 "af_packet_%s ioctl could not retrieve eth name, error: %d",
	 apif->host_if_name, rv);
      goto error;
    }

  clib_memcpy (ifr.ifr_hwaddr.sa_data, address, 6);
  ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER;

  if ((rv = ioctl (fd, SIOCSIFHWADDR, &ifr)) < 0)
    {
      vlib_log_warn (apm->log_class,
		     "af_packet_%s ioctl could not set mac, error: %d",
		     apif->host_if_name, rv);
      goto error;
    }

error:

  if (0 <= fd)
    close (fd);

  return 0;			/* no error */
}

static clib_error_t *
af_packet_interface_rx_mode_change (vnet_main_t *vnm, u32 hw_if_index, u32 qid,
				    vnet_hw_if_rx_mode mode)
{
  af_packet_main_t *apm = &af_packet_main;
  vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
  af_packet_if_t *apif;

  apif = vec_elt_at_index (apm->interfaces, hw->dev_instance);

  if (mode == VNET_HW_IF_RX_MODE_ADAPTIVE)
    {
      vlib_log_err (apm->log_class,
		    "af_packet_%s adaptive mode is not supported",
		    apif->host_if_name);
      return clib_error_return (
	0, "af_packet_%s adaptive mode is not supported", apif->host_if_name);
    }

  af_packet_queue_t *rx_queue = vec_elt_at_index (apif->rx_queues, qid);

  if (rx_queue->mode != mode)
    {
      rx_queue->mode = mode;

      if (mode == VNET_HW_IF_RX_MODE_POLLING)
	apm->polling_count++;
      else if (mode == VNET_HW_IF_RX_MODE_INTERRUPT && apm->polling_count > 0)
	apm->polling_count--;
    }

  return 0;
}

VNET_DEVICE_CLASS (af_packet_device_class) = {
  .name = "af-packet",
  .format_device_name = format_af_packet_device_name,
  .format_device = format_af_packet_device,
  .format_tx_trace = format_af_packet_tx_trace,
  .tx_function_n_errors = AF_PACKET_TX_N_ERROR,
  .tx_function_error_strings = af_packet_tx_func_error_strings,
  .rx_redirect_to_node = af_packet_set_interface_next_node,
  .clear_counters = af_packet_clear_hw_interface_counters,
  .admin_up_down_function = af_packet_interface_admin_up_down,
  .subif_add_del_function = af_packet_subif_add_del_function,
  .mac_addr_change_function = af_packet_set_mac_address_function,
  .rx_mode_change_function = af_packet_interface_rx_mode_change,
};

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */