summaryrefslogtreecommitdiffstats
path: root/drivers/net/thunderbolt.c
blob: c48c3a1eb1f8eba0629345f91b8f91a86f3597c3 (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
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
// SPDX-License-Identifier: GPL-2.0
/*
 * Networking over Thunderbolt cable using Apple ThunderboltIP protocol
 *
 * Copyright (C) 2017, Intel Corporation
 * Authors: Amir Levy <amir.jer.levy@intel.com>
 *          Michael Jamet <michael.jamet@intel.com>
 *          Mika Westerberg <mika.westerberg@linux.intel.com>
 */

#include <linux/atomic.h>
#include <linux/highmem.h>
#include <linux/if_vlan.h>
#include <linux/jhash.h>
#include <linux/module.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/sizes.h>
#include <linux/thunderbolt.h>
#include <linux/uuid.h>
#include <linux/workqueue.h>

#include <net/ip6_checksum.h>

/* Protocol timeouts in ms */
#define TBNET_LOGIN_DELAY	4500
#define TBNET_LOGIN_TIMEOUT	500
#define TBNET_LOGOUT_TIMEOUT	100

#define TBNET_RING_SIZE		256
#define TBNET_LOCAL_PATH	0xf
#define TBNET_LOGIN_RETRIES	60
#define TBNET_LOGOUT_RETRIES	5
#define TBNET_MATCH_FRAGS_ID	BIT(1)
#define TBNET_MAX_MTU		SZ_64K
#define TBNET_FRAME_SIZE	SZ_4K
#define TBNET_MAX_PAYLOAD_SIZE	\
	(TBNET_FRAME_SIZE - sizeof(struct thunderbolt_ip_frame_header))
/* Rx packets need to hold space for skb_shared_info */
#define TBNET_RX_MAX_SIZE	\
	(TBNET_FRAME_SIZE + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
#define TBNET_RX_PAGE_ORDER	get_order(TBNET_RX_MAX_SIZE)
#define TBNET_RX_PAGE_SIZE	(PAGE_SIZE << TBNET_RX_PAGE_ORDER)

#define TBNET_L0_PORT_NUM(route) ((route) & GENMASK(5, 0))

/**
 * struct thunderbolt_ip_frame_header - Header for each Thunderbolt frame
 * @frame_size: size of the data with the frame
 * @frame_index: running index on the frames
 * @frame_id: ID of the frame to match frames to specific packet
 * @frame_count: how many frames assembles a full packet
 *
 * Each data frame passed to the high-speed DMA ring has this header. If
 * the XDomain network directory announces that %TBNET_MATCH_FRAGS_ID is
 * supported then @frame_id is filled, otherwise it stays %0.
 */
struct thunderbolt_ip_frame_header {
	u32 frame_size;
	u16 frame_index;
	u16 frame_id;
	u32 frame_count;
};

enum thunderbolt_ip_frame_pdf {
	TBIP_PDF_FRAME_START = 1,
	TBIP_PDF_FRAME_END,
};

enum thunderbolt_ip_type {
	TBIP_LOGIN,
	TBIP_LOGIN_RESPONSE,
	TBIP_LOGOUT,
	TBIP_STATUS,
};

struct thunderbolt_ip_header {
	u32 route_hi;
	u32 route_lo;
	u32 length_sn;
	uuid_t uuid;
	uuid_t initiator_uuid;
	uuid_t target_uuid;
	u32 type;
	u32 command_id;
};

#define TBIP_HDR_LENGTH_MASK		GENMASK(5, 0)
#define TBIP_HDR_SN_MASK		GENMASK(28, 27)
#define TBIP_HDR_SN_SHIFT		27

struct thunderbolt_ip_login {
	struct thunderbolt_ip_header hdr;
	u32 proto_version;
	u32 transmit_path;
	u32 reserved[4];
};

#define TBIP_LOGIN_PROTO_VERSION	1

struct thunderbolt_ip_login_response {
	struct thunderbolt_ip_header hdr;
	u32 status;
	u32 receiver_mac[2];
	u32 receiver_mac_len;
	u32 reserved[4];
};

struct thunderbolt_ip_logout {
	struct thunderbolt_ip_header hdr;
};

struct thunderbolt_ip_status {
	struct thunderbolt_ip_header hdr;
	u32 status;
};

struct tbnet_stats {
	u64 tx_packets;
	u64 rx_packets;
	u64 tx_bytes;
	u64 rx_bytes;
	u64 rx_errors;
	u64 tx_errors;
	u64 rx_length_errors;
	u64 rx_over_errors;
	u64 rx_crc_errors;
	u64 rx_missed_errors;
};

struct tbnet_frame {
	struct net_device *dev;
	struct page *page;
	struct ring_frame frame;
};

struct tbnet_ring {
	struct tbnet_frame frames[TBNET_RING_SIZE];
	unsigned int cons;
	unsigned int prod;
	struct tb_ring *ring;
};

/**
 * struct tbnet - ThunderboltIP network driver private data
 * @svc: XDomain service the driver is bound to
 * @xd: XDomain the service blongs to
 * @handler: ThunderboltIP configuration protocol handler
 * @dev: Networking device
 * @napi: NAPI structure for Rx polling
 * @stats: Network statistics
 * @skb: Network packet that is currently processed on Rx path
 * @command_id: ID used for next configuration protocol packet
 * @login_sent: ThunderboltIP login message successfully sent
 * @login_received: ThunderboltIP login message received from the remote
 *		    host
 * @transmit_path: HopID the other end needs to use building the
 *		   opposite side path.
 * @connection_lock: Lock serializing access to @login_sent,
 *		     @login_received and @transmit_path.
 * @login_retries: Number of login retries currently done
 * @login_work: Worker to send ThunderboltIP login packets
 * @connected_work: Worker that finalizes the ThunderboltIP connection
 *		    setup and enables DMA paths for high speed data
 *		    transfers
 * @disconnect_work: Worker that handles tearing down the ThunderboltIP
 *		     connection
 * @rx_hdr: Copy of the currently processed Rx frame. Used when a
 *	    network packet consists of multiple Thunderbolt frames.
 *	    In host byte order.
 * @rx_ring: Software ring holding Rx frames
 * @frame_id: Frame ID use for next Tx packet
 *            (if %TBNET_MATCH_FRAGS_ID is supported in both ends)
 * @tx_ring: Software ring holding Tx frames
 */
struct tbnet {
	const struct tb_service *svc;
	struct tb_xdomain *xd;
	struct tb_protocol_handler handler;
	struct net_device *dev;
	struct napi_struct napi;
	struct tbnet_stats stats;
	struct sk_buff *skb;
	atomic_t command_id;
	bool login_sent;
	bool login_received;
	u32 transmit_path;
	struct mutex connection_lock;
	int login_retries;
	struct delayed_work login_work;
	struct work_struct connected_work;
	struct work_struct disconnect_work;
	struct thunderbolt_ip_frame_header rx_hdr;
	struct tbnet_ring rx_ring;
	atomic_t frame_id;
	struct tbnet_ring tx_ring;
};

/* Network property directory UUID: c66189ca-1cce-4195-bdb8-49592e5f5a4f */
static const uuid_t tbnet_dir_uuid =
	UUID_INIT(0xc66189ca, 0x1cce, 0x4195,
		  0xbd, 0xb8, 0x49, 0x59, 0x2e, 0x5f, 0x5a, 0x4f);

/* ThunderboltIP protocol UUID: 798f589e-3616-8a47-97c6-5664a920c8dd */
static const uuid_t tbnet_svc_uuid =
	UUID_INIT(0x798f589e, 0x3616, 0x8a47,
		  0x97, 0xc6, 0x56, 0x64, 0xa9, 0x20, 0xc8, 0xdd);

static struct tb_property_dir *tbnet_dir;

static void tbnet_fill_header(struct thunderbolt_ip_header *hdr, u64 route,
	u8 sequence, const uuid_t *initiator_uuid, const uuid_t *target_uuid,
	enum thunderbolt_ip_type type, size_t size, u32 command_id)
{
	u32 length_sn;

	/* Length does not include route_hi/lo and length_sn fields */
	length_sn = (size - 3 * 4) / 4;
	length_sn |= (sequence << TBIP_HDR_SN_SHIFT) & TBIP_HDR_SN_MASK;

	hdr->route_hi = upper_32_bits(route);
	hdr->route_lo = lower_32_bits(route);
	hdr->length_sn = length_sn;
	uuid_copy(&hdr->uuid, &tbnet_svc_uuid);
	uuid_copy(&hdr->initiator_uuid, initiator_uuid);
	uuid_copy(&hdr->target_uuid, target_uuid);
	hdr->type = type;
	hdr->command_id = command_id;
}

static int tbnet_login_response(struct tbnet *net, u64 route, u8 sequence,
				u32 command_id)
{
	struct thunderbolt_ip_login_response reply;
	struct tb_xdomain *xd = net->xd;

	memset(&reply, 0, sizeof(reply));
	tbnet_fill_header(&reply.hdr, route, sequence, xd->local_uuid,
			  xd->remote_uuid, TBIP_LOGIN_RESPONSE, sizeof(reply),
			  command_id);
	memcpy(reply.receiver_mac, net->dev->dev_addr, ETH_ALEN);
	reply.receiver_mac_len = ETH_ALEN;

	return tb_xdomain_response(xd, &reply, sizeof(reply),
				   TB_CFG_PKG_XDOMAIN_RESP);
}

static int tbnet_login_request(struct tbnet *net, u8 sequence)
{
	struct thunderbolt_ip_login_response reply;
	struct thunderbolt_ip_login request;
	struct tb_xdomain *xd = net->xd;

	memset(&request, 0, sizeof(request));
	tbnet_fill_header(&request.hdr, xd->route, sequence, xd->local_uuid,
			  xd->remote_uuid, TBIP_LOGIN, sizeof(request),
			  atomic_inc_return(&net->command_id));

	request.proto_version = TBIP_LOGIN_PROTO_VERSION;
	request.transmit_path = TBNET_LOCAL_PATH;

	return tb_xdomain_request(xd, &request, sizeof(request),
				  TB_CFG_PKG_XDOMAIN_RESP, &reply,
				  sizeof(reply), TB_CFG_PKG_XDOMAIN_RESP,
				  TBNET_LOGIN_TIMEOUT);
}

static int tbnet_logout_response(struct tbnet *net, u64 route, u8 sequence,
				 u32 command_id)
{
	struct thunderbolt_ip_status reply;
	struct tb_xdomain *xd = net->xd;

	memset(&reply, 0, sizeof(reply));
	tbnet_fill_header(&reply.hdr, route, sequence, xd->local_uuid,
			  xd->remote_uuid, TBIP_STATUS, sizeof(reply),
			  atomic_inc_return(&net->command_id));
	return tb_xdomain_response(xd, &reply, sizeof(reply),
				   TB_CFG_PKG_XDOMAIN_RESP);
}

static int tbnet_logout_request(struct tbnet *net)
{
	struct thunderbolt_ip_logout request;
	struct thunderbolt_ip_status reply;
	struct tb_xdomain *xd = net->xd;

	memset(&request, 0, sizeof(request));
	tbnet_fill_header(&request.hdr, xd->route, 0, xd->local_uuid,
			  xd->remote_uuid, TBIP_LOGOUT, sizeof(request),
			  atomic_inc_return(&net->command_id));

	return tb_xdomain_request(xd, &request, sizeof(request),
				  TB_CFG_PKG_XDOMAIN_RESP, &reply,
				  sizeof(reply), TB_CFG_PKG_XDOMAIN_RESP,
				  TBNET_LOGOUT_TIMEOUT);
}

static void start_login(struct tbnet *net)
{
	mutex_lock(&net->connection_lock);
	net->login_sent = false;
	net->login_received = false;
	mutex_unlock(&net->connection_lock);

	queue_delayed_work(system_long_wq, &net->login_work,
			   msecs_to_jiffies(1000));
}

static void stop_login(struct tbnet *net)
{
	cancel_delayed_work_sync(&net->login_work);
	cancel_work_sync(&net->connected_work);
}

static inline unsigned int tbnet_frame_size(const struct tbnet_frame *tf)
{
	return tf->frame.size ? : TBNET_FRAME_SIZE;
}

static void tbnet_free_buffers(struct tbnet_ring *ring)
{
	unsigned int i;

	for (i = 0; i < TBNET_RING_SIZE; i++) {
		struct device *dma_dev = tb_ring_dma_device(ring->ring);
		struct tbnet_frame *tf = &ring->frames[i];
		enum dma_data_direction dir;
		unsigned int order;
		size_t size;

		if (!tf->page)
			continue;

		if (ring->ring->is_tx) {
			dir = DMA_TO_DEVICE;
			order = 0;
			size = TBNET_FRAME_SIZE;
		} else {
			dir = DMA_FROM_DEVICE;
			order = TBNET_RX_PAGE_ORDER;
			size = TBNET_RX_PAGE_SIZE;
		}

		if (tf->frame.buffer_phy)
			dma_unmap_page(dma_dev, tf->frame.buffer_phy, size,
				       dir);

		__free_pages(tf->page, order);
		tf->page = NULL;
	}

	ring->cons = 0;
	ring->prod = 0;
}

static void tbnet_tear_down(struct tbnet *net, bool send_logout)
{
	netif_carrier_off(net->dev);
	netif_stop_queue(net->dev);

	stop_login(net);

	mutex_lock(&net->connection_lock);

	if (net->login_sent && net->login_received) {
		int retries = TBNET_LOGOUT_RETRIES;

		while (send_logout && retries-- > 0) {
			int ret = tbnet_logout_request(net);
			if (ret != -ETIMEDOUT)
				break;
		}

		tb_ring_stop(net->rx_ring.ring);
		tb_ring_stop(net->tx_ring.ring);
		tbnet_free_buffers(&net->rx_ring);
		tbnet_free_buffers(&net->tx_ring);

		if (tb_xdomain_disable_paths(net->xd))
			netdev_warn(net->dev, "failed to disable DMA paths\n");
	}

	net->login_retries = 0;
	net->login_sent = false;
	net->login_received = false;

	mutex_unlock(&net->connection_lock);
}

static int tbnet_handle_packet(const void *buf, size_t size, void *data)
{
	const struct thunderbolt_ip_login *pkg = buf;
	struct tbnet *net = data;
	u32 command_id;
	int ret = 0;
	u32 sequence;
	u64 route;

	/* Make sure the packet is for us */
	if (size < sizeof(struct thunderbolt_ip_header))
		return 0;
	if (!uuid_equal(&pkg->hdr.initiator_uuid, net->xd->remote_uuid))
		return 0;
	if (!uuid_equal(&pkg->hdr.target_uuid, net->xd->local_uuid))
		return 0;

	route = ((u64)pkg->hdr.route_hi << 32) | pkg->hdr.route_lo;
	route &= ~BIT_ULL(63);
	if (route != net->xd->route)
		return 0;

	sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
	sequence >>= TBIP_HDR_SN_SHIFT;
	command_id = pkg->hdr.command_id;

	switch (pkg->hdr.type) {
	case TBIP_LOGIN:
		if (!netif_running(net->dev))
			break;

		ret = tbnet_login_response(net, route, sequence,
					   pkg->hdr.command_id);
		if (!ret) {
			mutex_lock(&net->connection_lock);
			net->login_received = true;
			net->transmit_path = pkg->transmit_path;

			/* If we reached the number of max retries or
			 * previous logout, schedule another round of
			 * login retries
			 */
			if (net->login_retries >= TBNET_LOGIN_RETRIES ||
			    !net->login_sent) {
				net->login_retries = 0;
				queue_delayed_work(system_long_wq,
						   &net->login_work, 0);
			}
			mutex_unlock(&net->connection_lock);

			queue_work(system_long_wq, &net->connected_work);
		}
		break;

	case TBIP_LOGOUT:
		ret = tbnet_logout_response(net, route, sequence, command_id);
		if (!ret)
			queue_work(system_long_wq, &net->disconnect_work);
		break;

	default:
		return 0;
	}

	if (ret)
		netdev_warn(net->dev, "failed to send ThunderboltIP response\n");

	return 1;
}

static unsigned int tbnet_available_buffers(const struct tbnet_ring *ring)
{
	return ring->prod - ring->cons;
}

static int tbnet_alloc_rx_buffers(struct tbnet *net, unsigned int nbuffers)
{
	struct tbnet_ring *ring = &net->rx_ring;
	int ret;

	while (nbuffers--) {
		struct device *dma_dev = tb_ring_dma_device(ring->ring);
		unsigned int index = ring->prod & (TBNET_RING_SIZE - 1);
		struct tbnet_frame *tf = &ring->frames[index];
		dma_addr_t dma_addr;

		if (tf->page)
			break;

		/* Allocate page (order > 0) so that it can hold maximum
		 * ThunderboltIP frame (4kB) and the additional room for
		 * SKB shared info required by build_skb().
		 */
		tf->page = dev_alloc_pages(TBNET_RX_PAGE_ORDER);
		if (!tf->page) {
			ret = -ENOMEM;
			goto err_free;
		}

		dma_addr = dma_map_page(dma_dev, tf->page, 0,
					TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);
		if (dma_mapping_error(dma_dev, dma_addr)) {
			ret = -ENOMEM;
			goto err_free;
		}

		tf->frame.buffer_phy = dma_addr;
		tf->dev = net->dev;

		tb_ring_rx(ring->ring, &tf->frame);

		ring->prod++;
	}

	return 0;

err_free:
	tbnet_free_buffers(ring);
	return ret;
}

static struct tbnet_frame *tbnet_get_tx_buffer(struct tbnet *net)
{
	struct tbnet_ring *ring = &net->tx_ring;
	struct device *dma_dev = tb_ring_dma_device(ring->ring);
	struct tbnet_frame *tf;
	unsigned int index;

	if (!tbnet_available_buffers(ring))
		return NULL;

	index = ring->cons++ & (TBNET_RING_SIZE - 1);

	tf = &ring->frames[index];
	tf->frame.size = 0;

	dma_sync_single_for_cpu(dma_dev, tf->frame.buffer_phy,
				tbnet_frame_size(tf), DMA_TO_DEVICE);

	return tf;
}

static void tbnet_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
			      bool canceled)
{
	struct tbnet_frame *tf = container_of(frame, typeof(*tf), frame);
	struct tbnet *net = netdev_priv(tf->dev);

	/* Return buffer to the ring */
	net->tx_ring.prod++;

	if (tbnet_available_buffers(&net->tx_ring) >= TBNET_RING_SIZE / 2)
		netif_wake_queue(net->dev);
}

static int tbnet_alloc_tx_buffers(struct tbnet *net)
{
	struct tbnet_ring *ring = &net->tx_ring;
	struct device *dma_dev = tb_ring_dma_device(ring->ring);
	unsigned int i;

	for (i = 0; i < TBNET_RING_SIZE; i++) {
		struct tbnet_frame *tf = &ring->frames[i];
		dma_addr_t dma_addr;

		tf->page = alloc_page(GFP_KERNEL);
		if (!tf->page) {
			tbnet_free_buffers(ring);
			return -ENOMEM;
		}

		dma_addr = dma_map_page(dma_dev, tf->page, 0, TBNET_FRAME_SIZE,
					DMA_TO_DEVICE);
		if (dma_mapping_error(dma_dev, dma_addr)) {
			__free_page(tf->page);
			tf->page = NULL;
			tbnet_free_buffers(ring);
			return -ENOMEM;
		}

		tf->dev = net->dev;
		tf->frame.buffer_phy = dma_addr;
		tf->frame.callback = tbnet_tx_callback;
		tf->frame.sof = TBIP_PDF_FRAME_START;
		tf->frame.eof = TBIP_PDF_FRAME_END;
	}

	ring->cons = 0;
	ring->prod = TBNET_RING_SIZE - 1;

	return 0;
}

static void tbnet_connected_work(struct work_struct *work)
{
	struct tbnet *net = container_of(work, typeof(*net), connected_work);
	bool connected;
	int ret;

	if (netif_carrier_ok(net->dev))
		return;

	mutex_lock(&net->connection_lock);
	connected = net->login_sent && net->login_received;
	mutex_unlock(&net->connection_lock);

	if (!connected)
		return;

	/* Both logins successful so enable the high-speed DMA paths and
	 * start the network device queue.
	 */
	ret = tb_xdomain_enable_paths(net->xd, TBNET_LOCAL_PATH,
				      net->rx_ring.ring->hop,
				      net->transmit_path,
				      net->tx_ring.ring->hop);
	if (ret) {
		netdev_err(net->dev, "failed to enable DMA paths\n");
		return;
	}

	tb_ring_start(net->tx_ring.ring);
	tb_ring_start(net->rx_ring.ring);

	ret = tbnet_alloc_rx_buffers(net, TBNET_RING_SIZE);
	if (ret)
		goto err_stop_rings;

	ret = tbnet_alloc_tx_buffers(net);
	if (ret)
		goto err_free_rx_buffers;

	netif_carrier_on(net->dev);
	netif_start_queue(net->dev);
	return;

err_free_rx_buffers:
	tbnet_free_buffers(&net->rx_ring);
err_stop_rings:
	tb_ring_stop(net->rx_ring.ring);
	tb_ring_stop(net->tx_ring.ring);
}

static void tbnet_login_work(struct work_struct *work)
{
	struct tbnet *net = container_of(work, typeof(*net), login_work.work);
	unsigned long delay = msecs_to_jiffies(TBNET_LOGIN_DELAY);
	int ret;

	if (netif_carrier_ok(net->dev))
		return;

	ret = tbnet_login_request(net, net->login_retries % 4);
	if (ret) {
		if (net->login_retries++ < TBNET_LOGIN_RETRIES) {
			queue_delayed_work(system_long_wq, &net->login_work,
					   delay);
		} else {
			netdev_info(net->dev, "ThunderboltIP login timed out\n");
		}
	} else {
		net->login_retries = 0;

		mutex_lock(&net->connection_lock);
		net->login_sent = true;
		mutex_unlock(&net->connection_lock);

		queue_work(system_long_wq, &net->connected_work);
	}
}

static void tbnet_disconnect_work(struct work_struct *work)
{
	struct tbnet *net = container_of(work, typeof(*net), disconnect_work);

	tbnet_tear_down(net, false);
}

static bool tbnet_check_frame(struct tbnet *net, const struct tbnet_frame *tf,
			      const struct thunderbolt_ip_frame_header *hdr)
{
	u32 frame_id, frame_count, frame_size, frame_index;
	unsigned int size;

	if (tf->frame.flags & RING_DESC_CRC_ERROR) {
		net->stats.rx_crc_errors++;
		return false;
	} else if (tf->frame.flags & RING_DESC_BUFFER_OVERRUN) {
		net->stats.rx_over_errors++;
		return false;
	}

	/* Should be greater than just header i.e. contains data */
	size = tbnet_frame_size(tf);
	if (size <= sizeof(*hdr)) {
		net->stats.rx_length_errors++;
		return false;
	}

	frame_count = le32_to_cpu(hdr->frame_count);
	frame_size = le32_to_cpu(hdr->frame_size);
	frame_index = le16_to_cpu(hdr->frame_index);
	frame_id = le16_to_cpu(hdr->frame_id);

	if ((frame_size > size - sizeof(*hdr)) || !frame_size) {
		net->stats.rx_length_errors++;
		return false;
	}

	/* In case we're in the middle of packet, validate the frame
	 * header based on first fragment of the packet.
	 */
	if (net->skb && net->rx_hdr.frame_count) {
		/* Check the frame count fits the count field */
		if (frame_count != net->rx_hdr.frame_count) {
			net->stats.rx_length_errors++;
			return false;
		}

		/* Check the frame identifiers are incremented correctly,
		 * and id is matching.
		 */
		if (frame_index != net->rx_hdr.frame_index + 1 ||
		    frame_id != net->rx_hdr.frame_id) {
			net->stats.rx_missed_errors++;
			return false;
		}

		if (net->skb->len + frame_size > TBNET_MAX_MTU) {
			net->stats.rx_length_errors++;
			return false;
		}

		return true;
	}

	/* Start of packet, validate the frame header */
	if (frame_count == 0 || frame_count > TBNET_RING_SIZE / 4) {
		net->stats.rx_length_errors++;
		return false;
	}
	if (frame_index != 0) {
		net->stats.rx_missed_errors++;
		return false;
	}

	return true;
}

static int tbnet_poll(struct napi_struct *napi, int budget)
{
	struct tbnet *net = container_of(napi, struct tbnet, napi);
	unsigned int cleaned_count = tbnet_available_buffers(&net->rx_ring);
	struct device *dma_dev = tb_ring_dma_device(net->rx_ring.ring);
	unsigned int rx_packets = 0;

	while (rx_packets < budget) {
		const struct thunderbolt_ip_frame_header *hdr;
		unsigned int hdr_size = sizeof(*hdr);
		struct sk_buff *skb = NULL;
		struct ring_frame *frame;
		struct tbnet_frame *tf;
		struct page *page;
		bool last = true;
		u32 frame_size;

		/* Return some buffers to hardware, one at a time is too
		 * slow so allocate MAX_SKB_FRAGS buffers at the same
		 * time.
		 */
		if (cleaned_count >= MAX_SKB_FRAGS) {
			tbnet_alloc_rx_buffers(net, cleaned_count);
			cleaned_count = 0;
		}

		frame = tb_ring_poll(net->rx_ring.ring);
		if (!frame)
			break;

		dma_unmap_page(dma_dev, frame->buffer_phy,
			       TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);

		tf = container_of(frame, typeof(*tf), frame);

		page = tf->page;
		tf->page = NULL;
		net->rx_ring.cons++;
		cleaned_count++;

		hdr = page_address(page);
		if (!tbnet_check_frame(net, tf, hdr)) {
			__free_pages(page, TBNET_RX_PAGE_ORDER);
			dev_kfree_skb_any(net->skb);
			net->skb = NULL;
			continue;
		}

		frame_size = le32_to_cpu(hdr->frame_size);

		skb = net->skb;
		if (!skb) {
			skb = build_skb(page_address(page),
					TBNET_RX_PAGE_SIZE);
			if (!skb) {
				__free_pages(page, TBNET_RX_PAGE_ORDER);
				net->stats.rx_errors++;
				break;
			}

			skb_reserve(skb, hdr_size);
			skb_put(skb, frame_size);

			net->skb = skb;
		} else {
			skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
					page, hdr_size, frame_size,
					TBNET_RX_PAGE_SIZE - hdr_size);
		}

		net->rx_hdr.frame_size = frame_size;
		net->rx_hdr.frame_count = le32_to_cpu(hdr->frame_count);
		net->rx_hdr.frame_index = le16_to_cpu(hdr->frame_index);
		net->rx_hdr.frame_id = le16_to_cpu(hdr->frame_id);
		last = net->rx_hdr.frame_index == net->rx_hdr.frame_count - 1;

		rx_packets++;
		net->stats.rx_bytes += frame_size;

		if (last) {
			skb->protocol = eth_type_trans(skb, net->dev);
			napi_gro_receive(&net->napi, skb);
			net->skb = NULL;
		}
	}

	net->stats.rx_packets += rx_packets;

	if (cleaned_count)
		tbnet_alloc_rx_buffers(net, cleaned_count);

	if (rx_packets >= budget)
		return budget;

	napi_complete_done(napi, rx_packets);
	/* Re-enable the ring interrupt */
	tb_ring_poll_complete(net->rx_ring.ring);

	return rx_packets;
}

static void tbnet_start_poll(void *data)
{
	struct tbnet *net = data;

	napi_schedule(&net->napi);
}

static int tbnet_open(struct net_device *dev)
{
	struct tbnet *net = netdev_priv(dev);
	struct tb_xdomain *xd = net->xd;
	u16 sof_mask, eof_mask;
	struct tb_ring *ring;

	netif_carrier_off(dev);

	ring = tb_ring_alloc_tx(xd->tb->nhi, -1, TBNET_RING_SIZE,
				RING_FLAG_FRAME);
	if (!ring) {
		netdev_err(dev, "failed to allocate Tx ring\n");
		return -ENOMEM;
	}
	net->tx_ring.ring = ring;

	sof_mask = BIT(TBIP_PDF_FRAME_START);
	eof_mask = BIT(TBIP_PDF_FRAME_END);

	ring = tb_ring_alloc_rx(xd->tb->nhi, -1, TBNET_RING_SIZE,
				RING_FLAG_FRAME | RING_FLAG_E2E, sof_mask,
				eof_mask, tbnet_start_poll, net);
	if (!ring) {
		netdev_err(dev, "failed to allocate Rx ring\n");
		tb_ring_free(net->tx_ring.ring);
		net->tx_ring.ring = NULL;
		return -ENOMEM;
	}
	net->rx_ring.ring = ring;

	napi_enable(&net->napi);
	start_login(net);

	return 0;
}

static int tbnet_stop(struct net_device *dev)
{
	struct tbnet *net = netdev_priv(dev);

	napi_disable(&net->napi);

	cancel_work_sync(&net->disconnect_work);
	tbnet_tear_down(net, true);

	tb_ring_free(net->rx_ring.ring);
	net->rx_ring.ring = NULL;
	tb_ring_free(net->tx_ring.ring);
	net->tx_ring.ring = NULL;

	return 0;
}

static bool tbnet_xmit_csum_and_map(struct tbnet *net, struct sk_buff *skb,
	struct tbnet_frame **frames, u32 frame_count)
{
	struct thunderbolt_ip_frame_header *hdr = page_address(frames[0]->page);
	struct device *dma_dev = tb_ring_dma_device(net->tx_ring.ring);
	__wsum wsum = htonl(skb->len - skb_transport_offset(skb));
	unsigned int i, len, offset = skb_transport_offset(skb);
	__be16 protocol = skb->protocol;
	void *data = skb->data;
	void *dest = hdr + 1;
	__sum16 *tucso;

	if (skb->ip_summed != CHECKSUM_PARTIAL) {
		/* No need to calculate checksum so we just update the
		 * total frame count and sync the frames for DMA.
		 */
		for (i = 0; i < frame_count; i++) {
			hdr = page_address(frames[i]->page);
			hdr->frame_count = cpu_to_le32(frame_count);
			dma_sync_single_for_device(dma_dev,
				frames[i]->frame.buffer_phy,
				tbnet_frame_size(frames[i]), DMA_TO_DEVICE);
		}

		return true;
	}

	if (protocol == htons(ETH_P_8021Q)) {
		struct vlan_hdr *vhdr, vh;

		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(vh), &vh);
		if (!vhdr)
			return false;

		protocol = vhdr->h_vlan_encapsulated_proto;
	}

	/* Data points on the beginning of packet.
	 * Check is the checksum absolute place in the packet.
	 * ipcso will update IP checksum.
	 * tucso will update TCP/UPD checksum.
	 */
	if (protocol == htons(ETH_P_IP)) {
		__sum16 *ipcso = dest + ((void *)&(ip_hdr(skb)->check) - data);

		*ipcso = 0;
		*ipcso = ip_fast_csum(dest + skb_network_offset(skb),
				      ip_hdr(skb)->ihl);

		if (ip_hdr(skb)->protocol == IPPROTO_TCP)
			tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
		else if (ip_hdr(skb)->protocol == IPPROTO_UDP)
			tucso = dest + ((void *)&(udp_hdr(skb)->check) - data);
		else
			return false;

		*tucso = ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
					    ip_hdr(skb)->daddr, 0,
					    ip_hdr(skb)->protocol, 0);
	} else if (skb_is_gso_v6(skb)) {
		tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
		*tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
					  &ipv6_hdr(skb)->daddr, 0,
					  IPPROTO_TCP, 0);
		return false;
	} else if (protocol == htons(ETH_P_IPV6)) {
		tucso = dest + skb_checksum_start_offset(skb) + skb->csum_offset;
		*tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
					  &ipv6_hdr(skb)->daddr, 0,
					  ipv6_hdr(skb)->nexthdr, 0);
	} else {
		return false;
	}

	/* First frame was headers, rest of the frames contain data.
	 * Calculate checksum over each frame.
	 */
	for (i = 0; i < frame_count; i++) {
		hdr = page_address(frames[i]->page);
		dest = (void *)(hdr + 1) + offset;
		len = le32_to_cpu(hdr->frame_size) - offset;
		wsum = csum_partial(dest, len, wsum);
		hdr->frame_count = cpu_to_le32(frame_count);

		offset = 0;
	}

	*tucso = csum_fold(wsum);

	/* Checksum is finally calculated and we don't touch the memory
	 * anymore, so DMA sync the frames now.
	 */
	for (i = 0; i < frame_count; i++) {
		dma_sync_single_for_device(dma_dev, frames[i]->frame.buffer_phy,
			tbnet_frame_size(frames[i]), DMA_TO_DEVICE);
	}

	return true;
}

static void *tbnet_kmap_frag(struct sk_buff *skb, unsigned int frag_num,
			     unsigned int *len)
{
	const skb_frag_t *frag = &skb_shinfo(skb)->frags[frag_num];

	*len = skb_frag_size(frag);
	return kmap_atomic(skb_frag_page(frag)) + frag->page_offset;
}

static netdev_tx_t tbnet_start_xmit(struct sk_buff *skb,
				    struct net_device *dev)
{
	struct tbnet *net = netdev_priv(dev);
	struct tbnet_frame *frames[MAX_SKB_FRAGS];
	u16 frame_id = atomic_read(&net->frame_id);
	struct thunderbolt_ip_frame_header *hdr;
	unsigned int len = skb_headlen(skb);
	unsigned int data_len = skb->len;
	unsigned int nframes, i;
	unsigned int frag = 0;
	void *src = skb->data;
	u32 frame_index = 0;
	bool unmap = false;
	void *dest;

	nframes = DIV_ROUND_UP(data_len, TBNET_MAX_PAYLOAD_SIZE);
	if (tbnet_available_buffers(&net->tx_ring) < nframes) {
		netif_stop_queue(net->dev);
		return NETDEV_TX_BUSY;
	}

	frames[frame_index] = tbnet_get_tx_buffer(net);
	if (!frames[frame_index])
		goto err_drop;

	hdr = page_address(frames[frame_index]->page);
	dest = hdr + 1;

	/* If overall packet is bigger than the frame data size */
	while (data_len > TBNET_MAX_PAYLOAD_SIZE) {
		unsigned int size_left = TBNET_MAX_PAYLOAD_SIZE;

		hdr->frame_size = cpu_to_le32(TBNET_MAX_PAYLOAD_SIZE);
		hdr->frame_index = cpu_to_le16(frame_index);
		hdr->frame_id = cpu_to_le16(frame_id);

		do {
			if (len > size_left) {
				/* Copy data onto Tx buffer data with
				 * full frame size then break and go to
				 * next frame
				 */
				memcpy(dest, src, size_left);
				len -= size_left;
				dest += size_left;
				src += size_left;
				break;
			}

			memcpy(dest, src, len);
			size_left -= len;
			dest += len;

			if (unmap) {
				kunmap_atomic(src);
				unmap = false;
			}

			/* Ensure all fragments have been processed */
			if (frag < skb_shinfo(skb)->nr_frags) {
				/* Map and then unmap quickly */
				src = tbnet_kmap_frag(skb, frag++, &len);
				unmap = true;
			} else if (unlikely(size_left > 0)) {
				goto err_drop;
			}
		} while (size_left > 0);

		data_len -= TBNET_MAX_PAYLOAD_SIZE;
		frame_index++;

		frames[frame_index] = tbnet_get_tx_buffer(net);
		if (!frames[frame_index])
			goto err_drop;

		hdr = page_address(frames[frame_index]->page);
		dest = hdr + 1;
	}

	hdr->frame_size = cpu_to_le32(data_len);
	hdr->frame_index = cpu_to_le16(frame_index);
	hdr->frame_id = cpu_to_le16(frame_id);

	frames[frame_index]->frame.size = data_len + sizeof(*hdr);

	/* In case the remaining data_len is smaller than a frame */
	while (len < data_len) {
		memcpy(dest, src, len);
		data_len -= len;
		dest += len;

		if (unmap) {
			kunmap_atomic(src);
			unmap = false;
		}

		if (frag < skb_shinfo(skb)->nr_frags) {
			src = tbnet_kmap_frag(skb, frag++, &len);
			unmap = true;
		} else if (unlikely(data_len > 0)) {
			goto err_drop;
		}
	}

	memcpy(dest, src, data_len);

	if (unmap)
		kunmap_atomic(src);

	if (!tbnet_xmit_csum_and_map(net, skb, frames, frame_index + 1))
		goto err_drop;

	for (i = 0; i < frame_index + 1; i++)
		tb_ring_tx(net->tx_ring.ring, &frames[i]->frame);

	if (net->svc->prtcstns & TBNET_MATCH_FRAGS_ID)
		atomic_inc(&net->frame_id);

	net->stats.tx_packets++;
	net->stats.tx_bytes += skb->len;

	dev_consume_skb_any(skb);

	return NETDEV_TX_OK;

err_drop:
	/* We can re-use the buffers */
	net->tx_ring.cons -= frame_index;

	dev_kfree_skb_any(skb);
	net->stats.tx_errors++;

	return NETDEV_TX_OK;
}

static void tbnet_get_stats64(struct net_device *dev,
			      struct rtnl_link_stats64 *stats)
{
	struct tbnet *net = netdev_priv(dev);

	stats->tx_packets = net->stats.tx_packets;
	stats->rx_packets = net->stats.rx_packets;
	stats->tx_bytes = net->stats.tx_bytes;
	stats->rx_bytes = net->stats.rx_bytes;
	stats->rx_errors = net->stats.rx_errors + net->stats.rx_length_errors +
		net->stats.rx_over_errors + net->stats.rx_crc_errors +
		net->stats.rx_missed_errors;
	stats->tx_errors = net->stats.tx_errors;
	stats->rx_length_errors = net->stats.rx_length_errors;
	stats->rx_over_errors = net->stats.rx_over_errors;
	stats->rx_crc_errors = net->stats.rx_crc_errors;
	stats->rx_missed_errors = net->stats.rx_missed_errors;
}

static const struct net_device_ops tbnet_netdev_ops = {
	.ndo_open = tbnet_open,
	.ndo_stop = tbnet_stop,
	.ndo_start_xmit = tbnet_start_xmit,
	.ndo_get_stats64 = tbnet_get_stats64,
};

static void tbnet_generate_mac(struct net_device *dev)
{
	const struct tbnet *net = netdev_priv(dev);
	const struct tb_xdomain *xd = net->xd;
	u8 phy_port;
	u32 hash;

	phy_port = tb_phy_port_from_link(TBNET_L0_PORT_NUM(xd->route));

	/* Unicast and locally administered MAC */
	dev->dev_addr[0] = phy_port << 4 | 0x02;
	hash = jhash2((u32 *)xd->local_uuid, 4, 0);
	memcpy(dev->dev_addr + 1, &hash, sizeof(hash));
	hash = jhash2((u32 *)xd->local_uuid, 4, hash);
	dev->dev_addr[5] = hash & 0xff;
}

static int tbnet_probe(struct tb_service *svc, const struct tb_service_id *id)
{
	struct tb_xdomain *xd = tb_service_parent(svc);
	struct net_device *dev;
	struct tbnet *net;
	int ret;

	dev = alloc_etherdev(sizeof(*net));
	if (!dev)
		return -ENOMEM;

	SET_NETDEV_DEV(dev, &svc->dev);

	net = netdev_priv(dev);
	INIT_DELAYED_WORK(&net->login_work, tbnet_login_work);
	INIT_WORK(&net->connected_work, tbnet_connected_work);
	INIT_WORK(&net->disconnect_work, tbnet_disconnect_work);
	mutex_init(&net->connection_lock);
	atomic_set(&net->command_id, 0);
	atomic_set(&net->frame_id, 0);
	net->svc = svc;
	net->dev = dev;
	net->xd = xd;

	tbnet_generate_mac(dev);

	strcpy(dev->name, "thunderbolt%d");
	dev->netdev_ops = &tbnet_netdev_ops;

	/* ThunderboltIP takes advantage of TSO packets but instead of
	 * segmenting them we just split the packet into Thunderbolt
	 * frames (maximum payload size of each frame is 4084 bytes) and
	 * calculate checksum over the whole packet here.
	 *
	 * The receiving side does the opposite if the host OS supports
	 * LRO, otherwise it needs to split the large packet into MTU
	 * sized smaller packets.
	 *
	 * In order to receive large packets from the networking stack,
	 * we need to announce support for most of the offloading
	 * features here.
	 */
	dev->hw_features = NETIF_F_SG | NETIF_F_ALL_TSO | NETIF_F_GRO |
			   NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
	dev->features = dev->hw_features | NETIF_F_HIGHDMA;
	dev->hard_header_len += sizeof(struct thunderbolt_ip_frame_header);

	netif_napi_add(dev, &net->napi, tbnet_poll, NAPI_POLL_WEIGHT);

	/* MTU range: 68 - 65522 */
	dev->min_mtu = ETH_MIN_MTU;
	dev->max_mtu = TBNET_MAX_MTU - ETH_HLEN;

	net->handler.uuid = &tbnet_svc_uuid;
	net->handler.callback = tbnet_handle_packet,
	net->handler.data = net;
	tb_register_protocol_handler(&net->handler);

	tb_service_set_drvdata(svc, net);

	ret = register_netdev(dev);
	if (ret) {
		tb_unregister_protocol_handler(&net->handler);
		free_netdev(dev);
		return ret;
	}

	return 0;
}

static void tbnet_remove(struct tb_service *svc)
{
	struct tbnet *net = tb_service_get_drvdata(svc);

	unregister_netdev(net->dev);
	tb_unregister_protocol_handler(&net->handler);
	free_netdev(net->dev);
}

static void tbnet_shutdown(struct tb_service *svc)
{
	tbnet_tear_down(tb_service_get_drvdata(svc), true);
}

static int __maybe_unused tbnet_suspend(struct device *dev)
{
	struct tb_service *svc = tb_to_service(dev);
	struct tbnet *net = tb_service_get_drvdata(svc);

	stop_login(net);
	if (netif_running(net->dev)) {
		netif_device_detach(net->dev);
		tbnet_tear_down(net, true);
	}

	return 0;
}

static int __maybe_unused tbnet_resume(struct device *dev)
{
	struct tb_service *svc = tb_to_service(dev);
	struct tbnet *net = tb_service_get_drvdata(svc);

	netif_carrier_off(net->dev);
	if (netif_running(net->dev)) {
		netif_device_attach(net->dev);
		start_login(net);
	}

	return 0;
}

static const struct dev_pm_ops tbnet_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(tbnet_suspend, tbnet_resume)
};

static const struct tb_service_id tbnet_ids[] = {
	{ TB_SERVICE("network", 1) },
	{ },
};
MODULE_DEVICE_TABLE(tbsvc, tbnet_ids);

static struct tb_service_driver tbnet_driver = {
	.driver = {
		.owner = THIS_MODULE,
		.name = "thunderbolt-net",
		.pm = &tbnet_pm_ops,
	},
	.probe = tbnet_probe,
	.remove = tbnet_remove,
	.shutdown = tbnet_shutdown,
	.id_table = tbnet_ids,
};

static int __init tbnet_init(void)
{
	int ret;

	tbnet_dir = tb_property_create_dir(&tbnet_dir_uuid);
	if (!tbnet_dir)
		return -ENOMEM;

	tb_property_add_immediate(tbnet_dir, "prtcid", 1);
	tb_property_add_immediate(tbnet_dir, "prtcvers", 1);
	tb_property_add_immediate(tbnet_dir, "prtcrevs", 1);
	tb_property_add_immediate(tbnet_dir, "prtcstns",
				  TBNET_MATCH_FRAGS_ID);

	ret = tb_register_property_dir("network", tbnet_dir);
	if (ret) {
		tb_property_free_dir(tbnet_dir);
		return ret;
	}

	return tb_register_service_driver(&tbnet_driver);
}
module_init(tbnet_init);

static void __exit tbnet_exit(void)
{
	tb_unregister_service_driver(&tbnet_driver);
	tb_unregister_property_dir("network", tbnet_dir);
	tb_property_free_dir(tbnet_dir);
}
module_exit(tbnet_exit);

MODULE_AUTHOR("Amir Levy <amir.jer.levy@intel.com>");
MODULE_AUTHOR("Michael Jamet <michael.jamet@intel.com>");
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
MODULE_DESCRIPTION("Thunderbolt network driver");
MODULE_LICENSE("GPL v2");
OpenPOWER on IntegriCloud