summaryrefslogtreecommitdiff
path: root/net/ncsi/ncsi-manage.c
blob: 4789f868169597e8f12dc8cc8e998fc05124bfe1 (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
/*
 * Copyright Gavin Shan, IBM Corporation 2016.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>

#include <net/ncsi.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/addrconf.h>
#include <net/ipv6.h>
#include <net/if_inet6.h>

#include "internal.h"
#include "ncsi-pkt.h"

LIST_HEAD(ncsi_dev_list);
DEFINE_SPINLOCK(ncsi_dev_lock);

static inline int ncsi_filter_size(int table)
{
	int sizes[] = { 2, 6, 6, 6 };

	BUILD_BUG_ON(ARRAY_SIZE(sizes) != NCSI_FILTER_MAX);
	if (table < NCSI_FILTER_BASE || table >= NCSI_FILTER_MAX)
		return -EINVAL;

	return sizes[table];
}

int ncsi_find_filter(struct ncsi_channel *nc, int table, void *data)
{
	struct ncsi_channel_filter *ncf;
	void *bitmap;
	int index, size;
	unsigned long flags;

	ncf = nc->filters[table];
	if (!ncf)
		return -ENXIO;

	size = ncsi_filter_size(table);
	if (size < 0)
		return size;

	spin_lock_irqsave(&nc->lock, flags);
	bitmap = (void *)&ncf->bitmap;
	index = -1;
	while ((index = find_next_bit(bitmap, ncf->total, index + 1))
	       < ncf->total) {
		if (!memcmp(ncf->data + size * index, data, size)) {
			spin_unlock_irqrestore(&nc->lock, flags);
			return index;
		}
	}
	spin_unlock_irqrestore(&nc->lock, flags);

	return -ENOENT;
}

int ncsi_add_filter(struct ncsi_channel *nc, int table, void *data)
{
	struct ncsi_channel_filter *ncf;
	int index, size;
	void *bitmap;
	unsigned long flags;

	size = ncsi_filter_size(table);
	if (size < 0)
		return size;

	index = ncsi_find_filter(nc, table, data);
	if (index >= 0)
		return index;

	ncf = nc->filters[table];
	if (!ncf)
		return -ENODEV;

	spin_lock_irqsave(&nc->lock, flags);
	bitmap = (void *)&ncf->bitmap;
	do {
		index = find_next_zero_bit(bitmap, ncf->total, 0);
		if (index >= ncf->total) {
			spin_unlock_irqrestore(&nc->lock, flags);
			return -ENOSPC;
		}
	} while (test_and_set_bit(index, bitmap));

	memcpy(ncf->data + size * index, data, size);
	spin_unlock_irqrestore(&nc->lock, flags);

	return index;
}

int ncsi_remove_filter(struct ncsi_channel *nc, int table, int index)
{
	struct ncsi_channel_filter *ncf;
	int size;
	void *bitmap;
	unsigned long flags;

	size = ncsi_filter_size(table);
	if (size < 0)
		return size;

	ncf = nc->filters[table];
	if (!ncf || index >= ncf->total)
		return -ENODEV;

	spin_lock_irqsave(&nc->lock, flags);
	bitmap = (void *)&ncf->bitmap;
	if (test_and_clear_bit(index, bitmap))
		memset(ncf->data + size * index, 0, size);
	spin_unlock_irqrestore(&nc->lock, flags);

	return 0;
}

static void ncsi_report_link(struct ncsi_dev_priv *ndp, bool force_down)
{
	struct ncsi_dev *nd = &ndp->ndev;
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	unsigned long flags;

	nd->state = ncsi_dev_state_functional;
	if (force_down) {
		nd->link_up = 0;
		goto report;
	}

	nd->link_up = 0;
	NCSI_FOR_EACH_PACKAGE(ndp, np) {
		NCSI_FOR_EACH_CHANNEL(np, nc) {
			spin_lock_irqsave(&nc->lock, flags);

			if (!list_empty(&nc->link) ||
			    nc->state != NCSI_CHANNEL_ACTIVE) {
				spin_unlock_irqrestore(&nc->lock, flags);
				continue;
			}

			if (nc->modes[NCSI_MODE_LINK].data[2] & 0x1) {
				spin_unlock_irqrestore(&nc->lock, flags);
				nd->link_up = 1;
				goto report;
			}

			spin_unlock_irqrestore(&nc->lock, flags);
		}
	}

report:
	nd->handler(nd);
}

static void ncsi_channel_monitor(unsigned long data)
{
	struct ncsi_channel *nc = (struct ncsi_channel *)data;
	struct ncsi_package *np = nc->package;
	struct ncsi_dev_priv *ndp = np->ndp;
	struct ncsi_cmd_arg nca;
	bool enabled, chained;
	unsigned int monitor_state;
	unsigned long flags;
	int state, ret;

	spin_lock_irqsave(&nc->lock, flags);
	state = nc->state;
	chained = !list_empty(&nc->link);
	enabled = nc->monitor.enabled;
	monitor_state = nc->monitor.state;
	spin_unlock_irqrestore(&nc->lock, flags);

	if (!enabled || chained)
		return;
	if (state != NCSI_CHANNEL_INACTIVE &&
	    state != NCSI_CHANNEL_ACTIVE)
		return;

	switch (monitor_state) {
	case NCSI_CHANNEL_MONITOR_START:
	case NCSI_CHANNEL_MONITOR_RETRY:
		nca.ndp = ndp;
		nca.package = np->id;
		nca.channel = nc->id;
		nca.type = NCSI_PKT_CMD_GLS;
		nca.req_flags = 0;
		ret = ncsi_xmit_cmd(&nca);
		if (ret) {
			netdev_err(ndp->ndev.dev, "Error %d sending GLS\n",
				   ret);
			return;
		}

		break;
	case NCSI_CHANNEL_MONITOR_WAIT ... NCSI_CHANNEL_MONITOR_WAIT_MAX:
		break;
	default:
		if (!(ndp->flags & NCSI_DEV_HWA) &&
		    state == NCSI_CHANNEL_ACTIVE) {
			ncsi_report_link(ndp, true);
			ndp->flags |= NCSI_DEV_RESHUFFLE;
		}

		spin_lock_irqsave(&nc->lock, flags);
		nc->state = NCSI_CHANNEL_INVISIBLE;
		spin_unlock_irqrestore(&nc->lock, flags);

		spin_lock_irqsave(&ndp->lock, flags);
		nc->state = NCSI_CHANNEL_INACTIVE;
		list_add_tail_rcu(&nc->link, &ndp->channel_queue);
		spin_unlock_irqrestore(&ndp->lock, flags);
		ncsi_process_next_channel(ndp);
		return;
	}

	spin_lock_irqsave(&nc->lock, flags);
	nc->monitor.state++;
	spin_unlock_irqrestore(&nc->lock, flags);
	mod_timer(&nc->monitor.timer, jiffies + HZ);
}

void ncsi_start_channel_monitor(struct ncsi_channel *nc)
{
	unsigned long flags;

	spin_lock_irqsave(&nc->lock, flags);
	WARN_ON_ONCE(nc->monitor.enabled);
	nc->monitor.enabled = true;
	nc->monitor.state = NCSI_CHANNEL_MONITOR_START;
	spin_unlock_irqrestore(&nc->lock, flags);

	mod_timer(&nc->monitor.timer, jiffies + HZ);
}

void ncsi_stop_channel_monitor(struct ncsi_channel *nc)
{
	unsigned long flags;

	spin_lock_irqsave(&nc->lock, flags);
	if (!nc->monitor.enabled) {
		spin_unlock_irqrestore(&nc->lock, flags);
		return;
	}
	nc->monitor.enabled = false;
	spin_unlock_irqrestore(&nc->lock, flags);

	del_timer_sync(&nc->monitor.timer);
}

struct ncsi_channel *ncsi_find_channel(struct ncsi_package *np,
				       unsigned char id)
{
	struct ncsi_channel *nc;

	NCSI_FOR_EACH_CHANNEL(np, nc) {
		if (nc->id == id)
			return nc;
	}

	return NULL;
}

struct ncsi_channel *ncsi_add_channel(struct ncsi_package *np, unsigned char id)
{
	struct ncsi_channel *nc, *tmp;
	int index;
	unsigned long flags;

	nc = kzalloc(sizeof(*nc), GFP_ATOMIC);
	if (!nc)
		return NULL;

	nc->id = id;
	nc->package = np;
	nc->state = NCSI_CHANNEL_INACTIVE;
	nc->monitor.enabled = false;
	setup_timer(&nc->monitor.timer,
		    ncsi_channel_monitor, (unsigned long)nc);
	spin_lock_init(&nc->lock);
	INIT_LIST_HEAD(&nc->link);
	for (index = 0; index < NCSI_CAP_MAX; index++)
		nc->caps[index].index = index;
	for (index = 0; index < NCSI_MODE_MAX; index++)
		nc->modes[index].index = index;

	spin_lock_irqsave(&np->lock, flags);
	tmp = ncsi_find_channel(np, id);
	if (tmp) {
		spin_unlock_irqrestore(&np->lock, flags);
		kfree(nc);
		return tmp;
	}

	list_add_tail_rcu(&nc->node, &np->channels);
	np->channel_num++;
	spin_unlock_irqrestore(&np->lock, flags);

	return nc;
}

static void ncsi_remove_channel(struct ncsi_channel *nc)
{
	struct ncsi_package *np = nc->package;
	struct ncsi_channel_filter *ncf;
	unsigned long flags;
	int i;

	/* Release filters */
	spin_lock_irqsave(&nc->lock, flags);
	for (i = 0; i < NCSI_FILTER_MAX; i++) {
		ncf = nc->filters[i];
		if (!ncf)
			continue;

		nc->filters[i] = NULL;
		kfree(ncf);
	}

	nc->state = NCSI_CHANNEL_INACTIVE;
	spin_unlock_irqrestore(&nc->lock, flags);
	ncsi_stop_channel_monitor(nc);

	/* Remove and free channel */
	spin_lock_irqsave(&np->lock, flags);
	list_del_rcu(&nc->node);
	np->channel_num--;
	spin_unlock_irqrestore(&np->lock, flags);

	kfree(nc);
}

struct ncsi_package *ncsi_find_package(struct ncsi_dev_priv *ndp,
				       unsigned char id)
{
	struct ncsi_package *np;

	NCSI_FOR_EACH_PACKAGE(ndp, np) {
		if (np->id == id)
			return np;
	}

	return NULL;
}

struct ncsi_package *ncsi_add_package(struct ncsi_dev_priv *ndp,
				      unsigned char id)
{
	struct ncsi_package *np, *tmp;
	unsigned long flags;

	np = kzalloc(sizeof(*np), GFP_ATOMIC);
	if (!np)
		return NULL;

	np->id = id;
	np->ndp = ndp;
	spin_lock_init(&np->lock);
	INIT_LIST_HEAD(&np->channels);

	spin_lock_irqsave(&ndp->lock, flags);
	tmp = ncsi_find_package(ndp, id);
	if (tmp) {
		spin_unlock_irqrestore(&ndp->lock, flags);
		kfree(np);
		return tmp;
	}

	list_add_tail_rcu(&np->node, &ndp->packages);
	ndp->package_num++;
	spin_unlock_irqrestore(&ndp->lock, flags);

	return np;
}

void ncsi_remove_package(struct ncsi_package *np)
{
	struct ncsi_dev_priv *ndp = np->ndp;
	struct ncsi_channel *nc, *tmp;
	unsigned long flags;

	/* Release all child channels */
	list_for_each_entry_safe(nc, tmp, &np->channels, node)
		ncsi_remove_channel(nc);

	/* Remove and free package */
	spin_lock_irqsave(&ndp->lock, flags);
	list_del_rcu(&np->node);
	ndp->package_num--;
	spin_unlock_irqrestore(&ndp->lock, flags);

	kfree(np);
}

void ncsi_find_package_and_channel(struct ncsi_dev_priv *ndp,
				   unsigned char id,
				   struct ncsi_package **np,
				   struct ncsi_channel **nc)
{
	struct ncsi_package *p;
	struct ncsi_channel *c;

	p = ncsi_find_package(ndp, NCSI_PACKAGE_INDEX(id));
	c = p ? ncsi_find_channel(p, NCSI_CHANNEL_INDEX(id)) : NULL;

	if (np)
		*np = p;
	if (nc)
		*nc = c;
}

/* For two consecutive NCSI commands, the packet IDs shouldn't
 * be same. Otherwise, the bogus response might be replied. So
 * the available IDs are allocated in round-robin fashion.
 */
struct ncsi_request *ncsi_alloc_request(struct ncsi_dev_priv *ndp,
					unsigned int req_flags)
{
	struct ncsi_request *nr = NULL;
	int i, limit = ARRAY_SIZE(ndp->requests);
	unsigned long flags;

	/* Check if there is one available request until the ceiling */
	spin_lock_irqsave(&ndp->lock, flags);
	for (i = ndp->request_id; i < limit; i++) {
		if (ndp->requests[i].used)
			continue;

		nr = &ndp->requests[i];
		nr->used = true;
		nr->flags = req_flags;
		ndp->request_id = i + 1;
		goto found;
	}

	/* Fail back to check from the starting cursor */
	for (i = NCSI_REQ_START_IDX; i < ndp->request_id; i++) {
		if (ndp->requests[i].used)
			continue;

		nr = &ndp->requests[i];
		nr->used = true;
		nr->flags = req_flags;
		ndp->request_id = i + 1;
		goto found;
	}

found:
	spin_unlock_irqrestore(&ndp->lock, flags);
	return nr;
}

void ncsi_free_request(struct ncsi_request *nr)
{
	struct ncsi_dev_priv *ndp = nr->ndp;
	struct sk_buff *cmd, *rsp;
	unsigned long flags;
	bool driven;

	if (nr->enabled) {
		nr->enabled = false;
		del_timer_sync(&nr->timer);
	}

	spin_lock_irqsave(&ndp->lock, flags);
	cmd = nr->cmd;
	rsp = nr->rsp;
	nr->cmd = NULL;
	nr->rsp = NULL;
	nr->used = false;
	driven = !!(nr->flags & NCSI_REQ_FLAG_EVENT_DRIVEN);
	spin_unlock_irqrestore(&ndp->lock, flags);

	if (driven && cmd && --ndp->pending_req_num == 0)
		schedule_work(&ndp->work);

	/* Release command and response */
	consume_skb(cmd);
	consume_skb(rsp);
}

struct ncsi_dev *ncsi_find_dev(struct net_device *dev)
{
	struct ncsi_dev_priv *ndp;

	NCSI_FOR_EACH_DEV(ndp) {
		if (ndp->ndev.dev == dev)
			return &ndp->ndev;
	}

	return NULL;
}

static void ncsi_request_timeout(unsigned long data)
{
	struct ncsi_request *nr = (struct ncsi_request *)data;
	struct ncsi_dev_priv *ndp = nr->ndp;
	unsigned long flags;

	/* If the request already had associated response,
	 * let the response handler to release it.
	 */
	spin_lock_irqsave(&ndp->lock, flags);
	nr->enabled = false;
	if (nr->rsp || !nr->cmd) {
		spin_unlock_irqrestore(&ndp->lock, flags);
		return;
	}
	spin_unlock_irqrestore(&ndp->lock, flags);

	/* Release the request */
	ncsi_free_request(nr);
}

static void ncsi_suspend_channel(struct ncsi_dev_priv *ndp)
{
	struct ncsi_dev *nd = &ndp->ndev;
	struct ncsi_package *np = ndp->active_package;
	struct ncsi_channel *nc = ndp->active_channel;
	struct ncsi_cmd_arg nca;
	unsigned long flags;
	int ret;

	nca.ndp = ndp;
	nca.req_flags = NCSI_REQ_FLAG_EVENT_DRIVEN;
	switch (nd->state) {
	case ncsi_dev_state_suspend:
		nd->state = ncsi_dev_state_suspend_select;
		/* Fall through */
	case ncsi_dev_state_suspend_select:
		ndp->pending_req_num = 1;

		nca.type = NCSI_PKT_CMD_SP;
		nca.package = np->id;
		nca.channel = NCSI_RESERVED_CHANNEL;
		if (ndp->flags & NCSI_DEV_HWA)
			nca.bytes[0] = 0;
		else
			nca.bytes[0] = 1;

		/* To retrieve the last link states of channels in current
		 * package when current active channel needs fail over to
		 * another one. It means we will possibly select another
		 * channel as next active one. The link states of channels
		 * are most important factor of the selection. So we need
		 * accurate link states. Unfortunately, the link states on
		 * inactive channels can't be updated with LSC AEN in time.
		 */
		if (ndp->flags & NCSI_DEV_RESHUFFLE)
			nd->state = ncsi_dev_state_suspend_gls;
		else
			nd->state = ncsi_dev_state_suspend_dcnt;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		break;
	case ncsi_dev_state_suspend_gls:
		ndp->pending_req_num = np->channel_num;

		nca.type = NCSI_PKT_CMD_GLS;
		nca.package = np->id;

		nd->state = ncsi_dev_state_suspend_dcnt;
		NCSI_FOR_EACH_CHANNEL(np, nc) {
			nca.channel = nc->id;
			ret = ncsi_xmit_cmd(&nca);
			if (ret)
				goto error;
		}

		break;
	case ncsi_dev_state_suspend_dcnt:
		ndp->pending_req_num = 1;

		nca.type = NCSI_PKT_CMD_DCNT;
		nca.package = np->id;
		nca.channel = nc->id;

		nd->state = ncsi_dev_state_suspend_dc;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		break;
	case ncsi_dev_state_suspend_dc:
		ndp->pending_req_num = 1;

		nca.type = NCSI_PKT_CMD_DC;
		nca.package = np->id;
		nca.channel = nc->id;
		nca.bytes[0] = 1;

		nd->state = ncsi_dev_state_suspend_deselect;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		break;
	case ncsi_dev_state_suspend_deselect:
		ndp->pending_req_num = 1;

		nca.type = NCSI_PKT_CMD_DP;
		nca.package = np->id;
		nca.channel = NCSI_RESERVED_CHANNEL;

		nd->state = ncsi_dev_state_suspend_done;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		break;
	case ncsi_dev_state_suspend_done:
		spin_lock_irqsave(&nc->lock, flags);
		nc->state = NCSI_CHANNEL_INACTIVE;
		spin_unlock_irqrestore(&nc->lock, flags);
		ncsi_process_next_channel(ndp);

		break;
	default:
		netdev_warn(nd->dev, "Wrong NCSI state 0x%x in suspend\n",
			    nd->state);
	}

	return;
error:
	nd->state = ncsi_dev_state_functional;
}

static void ncsi_configure_channel(struct ncsi_dev_priv *ndp)
{
	struct ncsi_dev *nd = &ndp->ndev;
	struct net_device *dev = nd->dev;
	struct ncsi_package *np = ndp->active_package;
	struct ncsi_channel *nc = ndp->active_channel;
	struct ncsi_cmd_arg nca;
	unsigned char index;
	unsigned long flags;
	int ret;

	nca.ndp = ndp;
	nca.req_flags = NCSI_REQ_FLAG_EVENT_DRIVEN;
	switch (nd->state) {
	case ncsi_dev_state_config:
	case ncsi_dev_state_config_sp:
		ndp->pending_req_num = 1;

		/* Select the specific package */
		nca.type = NCSI_PKT_CMD_SP;
		if (ndp->flags & NCSI_DEV_HWA)
			nca.bytes[0] = 0;
		else
			nca.bytes[0] = 1;
		nca.package = np->id;
		nca.channel = NCSI_RESERVED_CHANNEL;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		nd->state = ncsi_dev_state_config_cis;
		break;
	case ncsi_dev_state_config_cis:
		ndp->pending_req_num = 1;

		/* Clear initial state */
		nca.type = NCSI_PKT_CMD_CIS;
		nca.package = np->id;
		nca.channel = nc->id;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		nd->state = ncsi_dev_state_config_sma;
		break;
	case ncsi_dev_state_config_sma:
	case ncsi_dev_state_config_ebf:
#if IS_ENABLED(CONFIG_IPV6)
	case ncsi_dev_state_config_egmf:
#endif
	case ncsi_dev_state_config_ecnt:
	case ncsi_dev_state_config_ec:
	case ncsi_dev_state_config_ae:
	case ncsi_dev_state_config_gls:
		ndp->pending_req_num = 1;

		nca.package = np->id;
		nca.channel = nc->id;

		/* Use first entry in unicast filter table. Note that
		 * the MAC filter table starts from entry 1 instead of
		 * 0.
		 */
		if (nd->state == ncsi_dev_state_config_sma) {
			nca.type = NCSI_PKT_CMD_SMA;
			for (index = 0; index < 6; index++)
				nca.bytes[index] = dev->dev_addr[index];
			nca.bytes[6] = 0x1;
			nca.bytes[7] = 0x1;
			nd->state = ncsi_dev_state_config_ebf;
		} else if (nd->state == ncsi_dev_state_config_ebf) {
			nca.type = NCSI_PKT_CMD_EBF;
			nca.dwords[0] = nc->caps[NCSI_CAP_BC].cap;
			nd->state = ncsi_dev_state_config_ecnt;
#if IS_ENABLED(CONFIG_IPV6)
			if (ndp->inet6_addr_num > 0 &&
			    (nc->caps[NCSI_CAP_GENERIC].cap &
			     NCSI_CAP_GENERIC_MC))
				nd->state = ncsi_dev_state_config_egmf;
			else
				nd->state = ncsi_dev_state_config_ecnt;
		} else if (nd->state == ncsi_dev_state_config_egmf) {
			nca.type = NCSI_PKT_CMD_EGMF;
			nca.dwords[0] = nc->caps[NCSI_CAP_MC].cap;
			nd->state = ncsi_dev_state_config_ecnt;
#endif /* CONFIG_IPV6 */
		} else if (nd->state == ncsi_dev_state_config_ecnt) {
			nca.type = NCSI_PKT_CMD_ECNT;
			nd->state = ncsi_dev_state_config_ec;
		} else if (nd->state == ncsi_dev_state_config_ec) {
			/* Enable AEN if it's supported */
			nca.type = NCSI_PKT_CMD_EC;
			nd->state = ncsi_dev_state_config_ae;
			if (!(nc->caps[NCSI_CAP_AEN].cap & NCSI_CAP_AEN_MASK))
				nd->state = ncsi_dev_state_config_gls;
		} else if (nd->state == ncsi_dev_state_config_ae) {
			nca.type = NCSI_PKT_CMD_AE;
			nca.bytes[0] = 0;
			nca.dwords[1] = nc->caps[NCSI_CAP_AEN].cap;
			nd->state = ncsi_dev_state_config_gls;
		} else if (nd->state == ncsi_dev_state_config_gls) {
			nca.type = NCSI_PKT_CMD_GLS;
			nd->state = ncsi_dev_state_config_done;
		}

		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;
		break;
	case ncsi_dev_state_config_done:
		spin_lock_irqsave(&nc->lock, flags);
		if (nc->modes[NCSI_MODE_LINK].data[2] & 0x1)
			nc->state = NCSI_CHANNEL_ACTIVE;
		else
			nc->state = NCSI_CHANNEL_INACTIVE;
		spin_unlock_irqrestore(&nc->lock, flags);

		ncsi_start_channel_monitor(nc);
		ncsi_process_next_channel(ndp);
		break;
	default:
		netdev_warn(dev, "Wrong NCSI state 0x%x in config\n",
			    nd->state);
	}

	return;

error:
	ncsi_report_link(ndp, true);
}

static int ncsi_choose_active_channel(struct ncsi_dev_priv *ndp)
{
	struct ncsi_package *np;
	struct ncsi_channel *nc, *found;
	struct ncsi_channel_mode *ncm;
	unsigned long flags;

	/* The search is done once an inactive channel with up
	 * link is found.
	 */
	found = NULL;
	NCSI_FOR_EACH_PACKAGE(ndp, np) {
		NCSI_FOR_EACH_CHANNEL(np, nc) {
			spin_lock_irqsave(&nc->lock, flags);

			if (!list_empty(&nc->link) ||
			    nc->state != NCSI_CHANNEL_INACTIVE) {
				spin_unlock_irqrestore(&nc->lock, flags);
				continue;
			}

			if (!found)
				found = nc;

			ncm = &nc->modes[NCSI_MODE_LINK];
			if (ncm->data[2] & 0x1) {
				spin_unlock_irqrestore(&nc->lock, flags);
				found = nc;
				goto out;
			}

			spin_unlock_irqrestore(&nc->lock, flags);
		}
	}

	if (!found) {
		ncsi_report_link(ndp, true);
		return -ENODEV;
	}

out:
	spin_lock_irqsave(&ndp->lock, flags);
	list_add_tail_rcu(&found->link, &ndp->channel_queue);
	spin_unlock_irqrestore(&ndp->lock, flags);

	return ncsi_process_next_channel(ndp);
}

static bool ncsi_check_hwa(struct ncsi_dev_priv *ndp)
{
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	unsigned int cap;

	/* The hardware arbitration is disabled if any one channel
	 * doesn't support explicitly.
	 */
	NCSI_FOR_EACH_PACKAGE(ndp, np) {
		NCSI_FOR_EACH_CHANNEL(np, nc) {
			cap = nc->caps[NCSI_CAP_GENERIC].cap;
			if (!(cap & NCSI_CAP_GENERIC_HWA) ||
			    (cap & NCSI_CAP_GENERIC_HWA_MASK) !=
			    NCSI_CAP_GENERIC_HWA_SUPPORT) {
				ndp->flags &= ~NCSI_DEV_HWA;
				return false;
			}
		}
	}

	ndp->flags |= NCSI_DEV_HWA;
	return true;
}

static int ncsi_enable_hwa(struct ncsi_dev_priv *ndp)
{
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	unsigned long flags;

	/* Move all available channels to processing queue */
	spin_lock_irqsave(&ndp->lock, flags);
	NCSI_FOR_EACH_PACKAGE(ndp, np) {
		NCSI_FOR_EACH_CHANNEL(np, nc) {
			WARN_ON_ONCE(nc->state != NCSI_CHANNEL_INACTIVE ||
				     !list_empty(&nc->link));
			ncsi_stop_channel_monitor(nc);
			list_add_tail_rcu(&nc->link, &ndp->channel_queue);
		}
	}
	spin_unlock_irqrestore(&ndp->lock, flags);

	/* We can have no channels in extremely case */
	if (list_empty(&ndp->channel_queue)) {
		ncsi_report_link(ndp, false);
		return -ENOENT;
	}

	return ncsi_process_next_channel(ndp);
}

static void ncsi_probe_channel(struct ncsi_dev_priv *ndp)
{
	struct ncsi_dev *nd = &ndp->ndev;
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	struct ncsi_cmd_arg nca;
	unsigned char index;
	int ret;

	nca.ndp = ndp;
	nca.req_flags = NCSI_REQ_FLAG_EVENT_DRIVEN;
	switch (nd->state) {
	case ncsi_dev_state_probe:
		nd->state = ncsi_dev_state_probe_deselect;
		/* Fall through */
	case ncsi_dev_state_probe_deselect:
		ndp->pending_req_num = 8;

		/* Deselect all possible packages */
		nca.type = NCSI_PKT_CMD_DP;
		nca.channel = NCSI_RESERVED_CHANNEL;
		for (index = 0; index < 8; index++) {
			nca.package = index;
			ret = ncsi_xmit_cmd(&nca);
			if (ret)
				goto error;
		}

		nd->state = ncsi_dev_state_probe_package;
		break;
	case ncsi_dev_state_probe_package:
		ndp->pending_req_num = 16;

		/* Select all possible packages */
		nca.type = NCSI_PKT_CMD_SP;
		nca.bytes[0] = 1;
		nca.channel = NCSI_RESERVED_CHANNEL;
		for (index = 0; index < 8; index++) {
			nca.package = index;
			ret = ncsi_xmit_cmd(&nca);
			if (ret)
				goto error;
		}

		/* Disable all possible packages */
		nca.type = NCSI_PKT_CMD_DP;
		for (index = 0; index < 8; index++) {
			nca.package = index;
			ret = ncsi_xmit_cmd(&nca);
			if (ret)
				goto error;
		}

		nd->state = ncsi_dev_state_probe_channel;
		break;
	case ncsi_dev_state_probe_channel:
		if (!ndp->active_package)
			ndp->active_package = list_first_or_null_rcu(
				&ndp->packages, struct ncsi_package, node);
		else if (list_is_last(&ndp->active_package->node,
				      &ndp->packages))
			ndp->active_package = NULL;
		else
			ndp->active_package = list_next_entry(
				ndp->active_package, node);

		/* All available packages and channels are enumerated. The
		 * enumeration happens for once when the NCSI interface is
		 * started. So we need continue to start the interface after
		 * the enumeration.
		 *
		 * We have to choose an active channel before configuring it.
		 * Note that we possibly don't have active channel in extreme
		 * situation.
		 */
		if (!ndp->active_package) {
			ndp->flags |= NCSI_DEV_PROBED;
			if (ncsi_check_hwa(ndp))
				ncsi_enable_hwa(ndp);
			else
				ncsi_choose_active_channel(ndp);
			return;
		}

		/* Select the active package */
		ndp->pending_req_num = 1;
		nca.type = NCSI_PKT_CMD_SP;
		nca.bytes[0] = 1;
		nca.package = ndp->active_package->id;
		nca.channel = NCSI_RESERVED_CHANNEL;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		nd->state = ncsi_dev_state_probe_cis;
		break;
	case ncsi_dev_state_probe_cis:
		ndp->pending_req_num = NCSI_RESERVED_CHANNEL;

		/* Clear initial state */
		nca.type = NCSI_PKT_CMD_CIS;
		nca.package = ndp->active_package->id;
		for (index = 0; index < NCSI_RESERVED_CHANNEL; index++) {
			nca.channel = index;
			ret = ncsi_xmit_cmd(&nca);
			if (ret)
				goto error;
		}

		nd->state = ncsi_dev_state_probe_gvi;
		break;
	case ncsi_dev_state_probe_gvi:
	case ncsi_dev_state_probe_gc:
	case ncsi_dev_state_probe_gls:
		np = ndp->active_package;
		ndp->pending_req_num = np->channel_num;

		/* Retrieve version, capability or link status */
		if (nd->state == ncsi_dev_state_probe_gvi)
			nca.type = NCSI_PKT_CMD_GVI;
		else if (nd->state == ncsi_dev_state_probe_gc)
			nca.type = NCSI_PKT_CMD_GC;
		else
			nca.type = NCSI_PKT_CMD_GLS;

		nca.package = np->id;
		NCSI_FOR_EACH_CHANNEL(np, nc) {
			nca.channel = nc->id;
			ret = ncsi_xmit_cmd(&nca);
			if (ret)
				goto error;
		}

		if (nd->state == ncsi_dev_state_probe_gvi)
			nd->state = ncsi_dev_state_probe_gc;
		else if (nd->state == ncsi_dev_state_probe_gc)
			nd->state = ncsi_dev_state_probe_gls;
		else
			nd->state = ncsi_dev_state_probe_dp;
		break;
	case ncsi_dev_state_probe_dp:
		ndp->pending_req_num = 1;

		/* Deselect the active package */
		nca.type = NCSI_PKT_CMD_DP;
		nca.package = ndp->active_package->id;
		nca.channel = NCSI_RESERVED_CHANNEL;
		ret = ncsi_xmit_cmd(&nca);
		if (ret)
			goto error;

		/* Scan channels in next package */
		nd->state = ncsi_dev_state_probe_channel;
		break;
	default:
		netdev_warn(nd->dev, "Wrong NCSI state 0x%0x in enumeration\n",
			    nd->state);
	}

	return;
error:
	ncsi_report_link(ndp, true);
}

static void ncsi_dev_work(struct work_struct *work)
{
	struct ncsi_dev_priv *ndp = container_of(work,
			struct ncsi_dev_priv, work);
	struct ncsi_dev *nd = &ndp->ndev;

	switch (nd->state & ncsi_dev_state_major) {
	case ncsi_dev_state_probe:
		ncsi_probe_channel(ndp);
		break;
	case ncsi_dev_state_suspend:
		ncsi_suspend_channel(ndp);
		break;
	case ncsi_dev_state_config:
		ncsi_configure_channel(ndp);
		break;
	default:
		netdev_warn(nd->dev, "Wrong NCSI state 0x%x in workqueue\n",
			    nd->state);
	}
}

int ncsi_process_next_channel(struct ncsi_dev_priv *ndp)
{
	struct ncsi_channel *nc;
	int old_state;
	unsigned long flags;

	spin_lock_irqsave(&ndp->lock, flags);
	nc = list_first_or_null_rcu(&ndp->channel_queue,
				    struct ncsi_channel, link);
	if (!nc) {
		spin_unlock_irqrestore(&ndp->lock, flags);
		goto out;
	}

	list_del_init(&nc->link);
	spin_unlock_irqrestore(&ndp->lock, flags);

	spin_lock_irqsave(&nc->lock, flags);
	old_state = nc->state;
	nc->state = NCSI_CHANNEL_INVISIBLE;
	spin_unlock_irqrestore(&nc->lock, flags);

	ndp->active_channel = nc;
	ndp->active_package = nc->package;

	switch (old_state) {
	case NCSI_CHANNEL_INACTIVE:
		ndp->ndev.state = ncsi_dev_state_config;
		ncsi_configure_channel(ndp);
		break;
	case NCSI_CHANNEL_ACTIVE:
		ndp->ndev.state = ncsi_dev_state_suspend;
		ncsi_suspend_channel(ndp);
		break;
	default:
		netdev_err(ndp->ndev.dev, "Invalid state 0x%x on %d:%d\n",
			   old_state, nc->package->id, nc->id);
		ncsi_report_link(ndp, false);
		return -EINVAL;
	}

	return 0;

out:
	ndp->active_channel = NULL;
	ndp->active_package = NULL;
	if (ndp->flags & NCSI_DEV_RESHUFFLE) {
		ndp->flags &= ~NCSI_DEV_RESHUFFLE;
		return ncsi_choose_active_channel(ndp);
	}

	ncsi_report_link(ndp, false);
	return -ENODEV;
}

#if IS_ENABLED(CONFIG_IPV6)
static int ncsi_inet6addr_event(struct notifier_block *this,
				unsigned long event, void *data)
{
	struct inet6_ifaddr *ifa = data;
	struct net_device *dev = ifa->idev->dev;
	struct ncsi_dev *nd = ncsi_find_dev(dev);
	struct ncsi_dev_priv *ndp = nd ? TO_NCSI_DEV_PRIV(nd) : NULL;
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	struct ncsi_cmd_arg nca;
	bool action;
	int ret;

	if (!ndp || (ipv6_addr_type(&ifa->addr) &
	    (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK)))
		return NOTIFY_OK;

	switch (event) {
	case NETDEV_UP:
		action = (++ndp->inet6_addr_num) == 1;
		nca.type = NCSI_PKT_CMD_EGMF;
		break;
	case NETDEV_DOWN:
		action = (--ndp->inet6_addr_num == 0);
		nca.type = NCSI_PKT_CMD_DGMF;
		break;
	default:
		return NOTIFY_OK;
	}

	/* We might not have active channel or packages. The IPv6
	 * required multicast will be enabled when active channel
	 * or packages are chosen.
	 */
	np = ndp->active_package;
	nc = ndp->active_channel;
	if (!action || !np || !nc)
		return NOTIFY_OK;

	/* We needn't enable or disable it if the function isn't supported */
	if (!(nc->caps[NCSI_CAP_GENERIC].cap & NCSI_CAP_GENERIC_MC))
		return NOTIFY_OK;

	nca.ndp = ndp;
	nca.req_flags = 0;
	nca.package = np->id;
	nca.channel = nc->id;
	nca.dwords[0] = nc->caps[NCSI_CAP_MC].cap;
	ret = ncsi_xmit_cmd(&nca);
	if (ret) {
		netdev_warn(dev, "Fail to %s global multicast filter (%d)\n",
			    (event == NETDEV_UP) ? "enable" : "disable", ret);
		return NOTIFY_DONE;
	}

	return NOTIFY_OK;
}

static struct notifier_block ncsi_inet6addr_notifier = {
	.notifier_call = ncsi_inet6addr_event,
};
#endif /* CONFIG_IPV6 */

struct ncsi_dev *ncsi_register_dev(struct net_device *dev,
				   void (*handler)(struct ncsi_dev *ndev))
{
	struct ncsi_dev_priv *ndp;
	struct ncsi_dev *nd;
	unsigned long flags;
	int i;

	/* Check if the device has been registered or not */
	nd = ncsi_find_dev(dev);
	if (nd)
		return nd;

	/* Create NCSI device */
	ndp = kzalloc(sizeof(*ndp), GFP_ATOMIC);
	if (!ndp)
		return NULL;

	nd = &ndp->ndev;
	nd->state = ncsi_dev_state_registered;
	nd->dev = dev;
	nd->handler = handler;
	ndp->pending_req_num = 0;
	INIT_LIST_HEAD(&ndp->channel_queue);
	INIT_WORK(&ndp->work, ncsi_dev_work);

	/* Initialize private NCSI device */
	spin_lock_init(&ndp->lock);
	INIT_LIST_HEAD(&ndp->packages);
	ndp->request_id = NCSI_REQ_START_IDX;
	for (i = 0; i < ARRAY_SIZE(ndp->requests); i++) {
		ndp->requests[i].id = i;
		ndp->requests[i].ndp = ndp;
		setup_timer(&ndp->requests[i].timer,
			    ncsi_request_timeout,
			    (unsigned long)&ndp->requests[i]);
	}

	spin_lock_irqsave(&ncsi_dev_lock, flags);
#if IS_ENABLED(CONFIG_IPV6)
	ndp->inet6_addr_num = 0;
	if (list_empty(&ncsi_dev_list))
		register_inet6addr_notifier(&ncsi_inet6addr_notifier);
#endif
	list_add_tail_rcu(&ndp->node, &ncsi_dev_list);
	spin_unlock_irqrestore(&ncsi_dev_lock, flags);

	/* Register NCSI packet Rx handler */
	ndp->ptype.type = cpu_to_be16(ETH_P_NCSI);
	ndp->ptype.func = ncsi_rcv_rsp;
	ndp->ptype.dev = dev;
	dev_add_pack(&ndp->ptype);

	return nd;
}
EXPORT_SYMBOL_GPL(ncsi_register_dev);

int ncsi_start_dev(struct ncsi_dev *nd)
{
	struct ncsi_dev_priv *ndp = TO_NCSI_DEV_PRIV(nd);
	int ret;

	if (nd->state != ncsi_dev_state_registered &&
	    nd->state != ncsi_dev_state_functional)
		return -ENOTTY;

	if (!(ndp->flags & NCSI_DEV_PROBED)) {
		nd->state = ncsi_dev_state_probe;
		schedule_work(&ndp->work);
		return 0;
	}

	if (ndp->flags & NCSI_DEV_HWA)
		ret = ncsi_enable_hwa(ndp);
	else
		ret = ncsi_choose_active_channel(ndp);

	return ret;
}
EXPORT_SYMBOL_GPL(ncsi_start_dev);

void ncsi_stop_dev(struct ncsi_dev *nd)
{
	struct ncsi_dev_priv *ndp = TO_NCSI_DEV_PRIV(nd);
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	bool chained;
	int old_state;
	unsigned long flags;

	/* Stop the channel monitor and reset channel's state */
	NCSI_FOR_EACH_PACKAGE(ndp, np) {
		NCSI_FOR_EACH_CHANNEL(np, nc) {
			ncsi_stop_channel_monitor(nc);

			spin_lock_irqsave(&nc->lock, flags);
			chained = !list_empty(&nc->link);
			old_state = nc->state;
			nc->state = NCSI_CHANNEL_INACTIVE;
			spin_unlock_irqrestore(&nc->lock, flags);

			WARN_ON_ONCE(chained ||
				     old_state == NCSI_CHANNEL_INVISIBLE);
		}
	}

	ncsi_report_link(ndp, true);
}
EXPORT_SYMBOL_GPL(ncsi_stop_dev);

void ncsi_unregister_dev(struct ncsi_dev *nd)
{
	struct ncsi_dev_priv *ndp = TO_NCSI_DEV_PRIV(nd);
	struct ncsi_package *np, *tmp;
	unsigned long flags;

	dev_remove_pack(&ndp->ptype);

	list_for_each_entry_safe(np, tmp, &ndp->packages, node)
		ncsi_remove_package(np);

	spin_lock_irqsave(&ncsi_dev_lock, flags);
	list_del_rcu(&ndp->node);
#if IS_ENABLED(CONFIG_IPV6)
	if (list_empty(&ncsi_dev_list))
		unregister_inet6addr_notifier(&ncsi_inet6addr_notifier);
#endif
	spin_unlock_irqrestore(&ncsi_dev_lock, flags);

	kfree(ndp);
}
EXPORT_SYMBOL_GPL(ncsi_unregister_dev);