summaryrefslogtreecommitdiff
path: root/drivers/infiniband/core/mad_rmpp.c
blob: 382941b46e43aaef78219ad3437598b87a63504e (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
/*
 * Copyright (c) 2005 Intel Inc. All rights reserved.
 * Copyright (c) 2005-2006 Voltaire, Inc. All rights reserved.
 * Copyright (c) 2014 Intel Corporation.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/slab.h>

#include "mad_priv.h"
#include "mad_rmpp.h"

enum rmpp_state {
	RMPP_STATE_ACTIVE,
	RMPP_STATE_TIMEOUT,
	RMPP_STATE_COMPLETE,
	RMPP_STATE_CANCELING
};

struct mad_rmpp_recv {
	struct ib_mad_agent_private *agent;
	struct list_head list;
	struct delayed_work timeout_work;
	struct delayed_work cleanup_work;
	struct completion comp;
	enum rmpp_state state;
	spinlock_t lock;
	atomic_t refcount;

	struct ib_ah *ah;
	struct ib_mad_recv_wc *rmpp_wc;
	struct ib_mad_recv_buf *cur_seg_buf;
	int last_ack;
	int seg_num;
	int newwin;
	int repwin;

	__be64 tid;
	u32 src_qp;
	u16 slid;
	u8 mgmt_class;
	u8 class_version;
	u8 method;
	u8 base_version;
};

static inline void deref_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
{
	if (atomic_dec_and_test(&rmpp_recv->refcount))
		complete(&rmpp_recv->comp);
}

static void destroy_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
{
	deref_rmpp_recv(rmpp_recv);
	wait_for_completion(&rmpp_recv->comp);
	ib_destroy_ah(rmpp_recv->ah);
	kfree(rmpp_recv);
}

void ib_cancel_rmpp_recvs(struct ib_mad_agent_private *agent)
{
	struct mad_rmpp_recv *rmpp_recv, *temp_rmpp_recv;
	unsigned long flags;

	spin_lock_irqsave(&agent->lock, flags);
	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
		if (rmpp_recv->state != RMPP_STATE_COMPLETE)
			ib_free_recv_mad(rmpp_recv->rmpp_wc);
		rmpp_recv->state = RMPP_STATE_CANCELING;
	}
	spin_unlock_irqrestore(&agent->lock, flags);

	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
		cancel_delayed_work(&rmpp_recv->timeout_work);
		cancel_delayed_work(&rmpp_recv->cleanup_work);
	}

	flush_workqueue(agent->qp_info->port_priv->wq);

	list_for_each_entry_safe(rmpp_recv, temp_rmpp_recv,
				 &agent->rmpp_list, list) {
		list_del(&rmpp_recv->list);
		destroy_rmpp_recv(rmpp_recv);
	}
}

static void format_ack(struct ib_mad_send_buf *msg,
		       struct ib_rmpp_mad *data,
		       struct mad_rmpp_recv *rmpp_recv)
{
	struct ib_rmpp_mad *ack = msg->mad;
	unsigned long flags;

	memcpy(ack, &data->mad_hdr, msg->hdr_len);

	ack->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
	ack->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ACK;
	ib_set_rmpp_flags(&ack->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);

	spin_lock_irqsave(&rmpp_recv->lock, flags);
	rmpp_recv->last_ack = rmpp_recv->seg_num;
	ack->rmpp_hdr.seg_num = cpu_to_be32(rmpp_recv->seg_num);
	ack->rmpp_hdr.paylen_newwin = cpu_to_be32(rmpp_recv->newwin);
	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
}

static void ack_recv(struct mad_rmpp_recv *rmpp_recv,
		     struct ib_mad_recv_wc *recv_wc)
{
	struct ib_mad_send_buf *msg;
	int ret, hdr_len;

	hdr_len = ib_get_mad_data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
	msg = ib_create_send_mad(&rmpp_recv->agent->agent, recv_wc->wc->src_qp,
				 recv_wc->wc->pkey_index, 1, hdr_len,
				 0, GFP_KERNEL,
				 IB_MGMT_BASE_VERSION);
	if (IS_ERR(msg))
		return;

	format_ack(msg, (struct ib_rmpp_mad *) recv_wc->recv_buf.mad, rmpp_recv);
	msg->ah = rmpp_recv->ah;
	ret = ib_post_send_mad(msg, NULL);
	if (ret)
		ib_free_send_mad(msg);
}

static struct ib_mad_send_buf *alloc_response_msg(struct ib_mad_agent *agent,
						  struct ib_mad_recv_wc *recv_wc)
{
	struct ib_mad_send_buf *msg;
	struct ib_ah *ah;
	int hdr_len;

	ah = ib_create_ah_from_wc(agent->qp->pd, recv_wc->wc,
				  recv_wc->recv_buf.grh, agent->port_num);
	if (IS_ERR(ah))
		return (void *) ah;

	hdr_len = ib_get_mad_data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
	msg = ib_create_send_mad(agent, recv_wc->wc->src_qp,
				 recv_wc->wc->pkey_index, 1,
				 hdr_len, 0, GFP_KERNEL,
				 IB_MGMT_BASE_VERSION);
	if (IS_ERR(msg))
		ib_destroy_ah(ah);
	else {
		msg->ah = ah;
		msg->context[0] = ah;
	}

	return msg;
}

static void ack_ds_ack(struct ib_mad_agent_private *agent,
		       struct ib_mad_recv_wc *recv_wc)
{
	struct ib_mad_send_buf *msg;
	struct ib_rmpp_mad *rmpp_mad;
	int ret;

	msg = alloc_response_msg(&agent->agent, recv_wc);
	if (IS_ERR(msg))
		return;

	rmpp_mad = msg->mad;
	memcpy(rmpp_mad, recv_wc->recv_buf.mad, msg->hdr_len);

	rmpp_mad->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
	rmpp_mad->rmpp_hdr.seg_num = 0;
	rmpp_mad->rmpp_hdr.paylen_newwin = cpu_to_be32(1);

	ret = ib_post_send_mad(msg, NULL);
	if (ret) {
		ib_destroy_ah(msg->ah);
		ib_free_send_mad(msg);
	}
}

void ib_rmpp_send_handler(struct ib_mad_send_wc *mad_send_wc)
{
	if (mad_send_wc->send_buf->context[0] == mad_send_wc->send_buf->ah)
		ib_destroy_ah(mad_send_wc->send_buf->ah);
	ib_free_send_mad(mad_send_wc->send_buf);
}

static void nack_recv(struct ib_mad_agent_private *agent,
		      struct ib_mad_recv_wc *recv_wc, u8 rmpp_status)
{
	struct ib_mad_send_buf *msg;
	struct ib_rmpp_mad *rmpp_mad;
	int ret;

	msg = alloc_response_msg(&agent->agent, recv_wc);
	if (IS_ERR(msg))
		return;

	rmpp_mad = msg->mad;
	memcpy(rmpp_mad, recv_wc->recv_buf.mad, msg->hdr_len);

	rmpp_mad->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
	rmpp_mad->rmpp_hdr.rmpp_version = IB_MGMT_RMPP_VERSION;
	rmpp_mad->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ABORT;
	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
	rmpp_mad->rmpp_hdr.rmpp_status = rmpp_status;
	rmpp_mad->rmpp_hdr.seg_num = 0;
	rmpp_mad->rmpp_hdr.paylen_newwin = 0;

	ret = ib_post_send_mad(msg, NULL);
	if (ret) {
		ib_destroy_ah(msg->ah);
		ib_free_send_mad(msg);
	}
}

static void recv_timeout_handler(struct work_struct *work)
{
	struct mad_rmpp_recv *rmpp_recv =
		container_of(work, struct mad_rmpp_recv, timeout_work.work);
	struct ib_mad_recv_wc *rmpp_wc;
	unsigned long flags;

	spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
	if (rmpp_recv->state != RMPP_STATE_ACTIVE) {
		spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
		return;
	}
	rmpp_recv->state = RMPP_STATE_TIMEOUT;
	list_del(&rmpp_recv->list);
	spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);

	rmpp_wc = rmpp_recv->rmpp_wc;
	nack_recv(rmpp_recv->agent, rmpp_wc, IB_MGMT_RMPP_STATUS_T2L);
	destroy_rmpp_recv(rmpp_recv);
	ib_free_recv_mad(rmpp_wc);
}

static void recv_cleanup_handler(struct work_struct *work)
{
	struct mad_rmpp_recv *rmpp_recv =
		container_of(work, struct mad_rmpp_recv, cleanup_work.work);
	unsigned long flags;

	spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
	if (rmpp_recv->state == RMPP_STATE_CANCELING) {
		spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
		return;
	}
	list_del(&rmpp_recv->list);
	spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
	destroy_rmpp_recv(rmpp_recv);
}

static struct mad_rmpp_recv *
create_rmpp_recv(struct ib_mad_agent_private *agent,
		 struct ib_mad_recv_wc *mad_recv_wc)
{
	struct mad_rmpp_recv *rmpp_recv;
	struct ib_mad_hdr *mad_hdr;

	rmpp_recv = kmalloc(sizeof *rmpp_recv, GFP_KERNEL);
	if (!rmpp_recv)
		return NULL;

	rmpp_recv->ah = ib_create_ah_from_wc(agent->agent.qp->pd,
					     mad_recv_wc->wc,
					     mad_recv_wc->recv_buf.grh,
					     agent->agent.port_num);
	if (IS_ERR(rmpp_recv->ah))
		goto error;

	rmpp_recv->agent = agent;
	init_completion(&rmpp_recv->comp);
	INIT_DELAYED_WORK(&rmpp_recv->timeout_work, recv_timeout_handler);
	INIT_DELAYED_WORK(&rmpp_recv->cleanup_work, recv_cleanup_handler);
	spin_lock_init(&rmpp_recv->lock);
	rmpp_recv->state = RMPP_STATE_ACTIVE;
	atomic_set(&rmpp_recv->refcount, 1);

	rmpp_recv->rmpp_wc = mad_recv_wc;
	rmpp_recv->cur_seg_buf = &mad_recv_wc->recv_buf;
	rmpp_recv->newwin = 1;
	rmpp_recv->seg_num = 1;
	rmpp_recv->last_ack = 0;
	rmpp_recv->repwin = 1;

	mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;
	rmpp_recv->tid = mad_hdr->tid;
	rmpp_recv->src_qp = mad_recv_wc->wc->src_qp;
	rmpp_recv->slid = mad_recv_wc->wc->slid;
	rmpp_recv->mgmt_class = mad_hdr->mgmt_class;
	rmpp_recv->class_version = mad_hdr->class_version;
	rmpp_recv->method  = mad_hdr->method;
	rmpp_recv->base_version  = mad_hdr->base_version;
	return rmpp_recv;

error:	kfree(rmpp_recv);
	return NULL;
}

static struct mad_rmpp_recv *
find_rmpp_recv(struct ib_mad_agent_private *agent,
	       struct ib_mad_recv_wc *mad_recv_wc)
{
	struct mad_rmpp_recv *rmpp_recv;
	struct ib_mad_hdr *mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;

	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
		if (rmpp_recv->tid == mad_hdr->tid &&
		    rmpp_recv->src_qp == mad_recv_wc->wc->src_qp &&
		    rmpp_recv->slid == mad_recv_wc->wc->slid &&
		    rmpp_recv->mgmt_class == mad_hdr->mgmt_class &&
		    rmpp_recv->class_version == mad_hdr->class_version &&
		    rmpp_recv->method == mad_hdr->method)
			return rmpp_recv;
	}
	return NULL;
}

static struct mad_rmpp_recv *
acquire_rmpp_recv(struct ib_mad_agent_private *agent,
		  struct ib_mad_recv_wc *mad_recv_wc)
{
	struct mad_rmpp_recv *rmpp_recv;
	unsigned long flags;

	spin_lock_irqsave(&agent->lock, flags);
	rmpp_recv = find_rmpp_recv(agent, mad_recv_wc);
	if (rmpp_recv)
		atomic_inc(&rmpp_recv->refcount);
	spin_unlock_irqrestore(&agent->lock, flags);
	return rmpp_recv;
}

static struct mad_rmpp_recv *
insert_rmpp_recv(struct ib_mad_agent_private *agent,
		 struct mad_rmpp_recv *rmpp_recv)
{
	struct mad_rmpp_recv *cur_rmpp_recv;

	cur_rmpp_recv = find_rmpp_recv(agent, rmpp_recv->rmpp_wc);
	if (!cur_rmpp_recv)
		list_add_tail(&rmpp_recv->list, &agent->rmpp_list);

	return cur_rmpp_recv;
}

static inline int get_last_flag(struct ib_mad_recv_buf *seg)
{
	struct ib_rmpp_mad *rmpp_mad;

	rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
	return ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) & IB_MGMT_RMPP_FLAG_LAST;
}

static inline int get_seg_num(struct ib_mad_recv_buf *seg)
{
	struct ib_rmpp_mad *rmpp_mad;

	rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
	return be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
}

static inline struct ib_mad_recv_buf * get_next_seg(struct list_head *rmpp_list,
						    struct ib_mad_recv_buf *seg)
{
	if (seg->list.next == rmpp_list)
		return NULL;

	return container_of(seg->list.next, struct ib_mad_recv_buf, list);
}

static inline int window_size(struct ib_mad_agent_private *agent)
{
	return max(agent->qp_info->recv_queue.max_active >> 3, 1);
}

static struct ib_mad_recv_buf * find_seg_location(struct list_head *rmpp_list,
						  int seg_num)
{
	struct ib_mad_recv_buf *seg_buf;
	int cur_seg_num;

	list_for_each_entry_reverse(seg_buf, rmpp_list, list) {
		cur_seg_num = get_seg_num(seg_buf);
		if (seg_num > cur_seg_num)
			return seg_buf;
		if (seg_num == cur_seg_num)
			break;
	}
	return NULL;
}

static void update_seg_num(struct mad_rmpp_recv *rmpp_recv,
			   struct ib_mad_recv_buf *new_buf)
{
	struct list_head *rmpp_list = &rmpp_recv->rmpp_wc->rmpp_list;

	while (new_buf && (get_seg_num(new_buf) == rmpp_recv->seg_num + 1)) {
		rmpp_recv->cur_seg_buf = new_buf;
		rmpp_recv->seg_num++;
		new_buf = get_next_seg(rmpp_list, new_buf);
	}
}

static inline int get_mad_len(struct mad_rmpp_recv *rmpp_recv)
{
	struct ib_rmpp_mad *rmpp_mad;
	int hdr_size, data_size, pad;
	bool opa = rdma_cap_opa_mad(rmpp_recv->agent->qp_info->port_priv->device,
				    rmpp_recv->agent->qp_info->port_priv->port_num);

	rmpp_mad = (struct ib_rmpp_mad *)rmpp_recv->cur_seg_buf->mad;

	hdr_size = ib_get_mad_data_offset(rmpp_mad->mad_hdr.mgmt_class);
	if (opa && rmpp_recv->base_version == OPA_MGMT_BASE_VERSION) {
		data_size = sizeof(struct opa_rmpp_mad) - hdr_size;
		pad = OPA_MGMT_RMPP_DATA - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
		if (pad > OPA_MGMT_RMPP_DATA || pad < 0)
			pad = 0;
	} else {
		data_size = sizeof(struct ib_rmpp_mad) - hdr_size;
		pad = IB_MGMT_RMPP_DATA - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
		if (pad > IB_MGMT_RMPP_DATA || pad < 0)
			pad = 0;
	}

	return hdr_size + rmpp_recv->seg_num * data_size - pad;
}

static struct ib_mad_recv_wc * complete_rmpp(struct mad_rmpp_recv *rmpp_recv)
{
	struct ib_mad_recv_wc *rmpp_wc;

	ack_recv(rmpp_recv, rmpp_recv->rmpp_wc);
	if (rmpp_recv->seg_num > 1)
		cancel_delayed_work(&rmpp_recv->timeout_work);

	rmpp_wc = rmpp_recv->rmpp_wc;
	rmpp_wc->mad_len = get_mad_len(rmpp_recv);
	/* 10 seconds until we can find the packet lifetime */
	queue_delayed_work(rmpp_recv->agent->qp_info->port_priv->wq,
			   &rmpp_recv->cleanup_work, msecs_to_jiffies(10000));
	return rmpp_wc;
}

static struct ib_mad_recv_wc *
continue_rmpp(struct ib_mad_agent_private *agent,
	      struct ib_mad_recv_wc *mad_recv_wc)
{
	struct mad_rmpp_recv *rmpp_recv;
	struct ib_mad_recv_buf *prev_buf;
	struct ib_mad_recv_wc *done_wc;
	int seg_num;
	unsigned long flags;

	rmpp_recv = acquire_rmpp_recv(agent, mad_recv_wc);
	if (!rmpp_recv)
		goto drop1;

	seg_num = get_seg_num(&mad_recv_wc->recv_buf);

	spin_lock_irqsave(&rmpp_recv->lock, flags);
	if ((rmpp_recv->state == RMPP_STATE_TIMEOUT) ||
	    (seg_num > rmpp_recv->newwin))
		goto drop3;

	if ((seg_num <= rmpp_recv->last_ack) ||
	    (rmpp_recv->state == RMPP_STATE_COMPLETE)) {
		spin_unlock_irqrestore(&rmpp_recv->lock, flags);
		ack_recv(rmpp_recv, mad_recv_wc);
		goto drop2;
	}

	prev_buf = find_seg_location(&rmpp_recv->rmpp_wc->rmpp_list, seg_num);
	if (!prev_buf)
		goto drop3;

	done_wc = NULL;
	list_add(&mad_recv_wc->recv_buf.list, &prev_buf->list);
	if (rmpp_recv->cur_seg_buf == prev_buf) {
		update_seg_num(rmpp_recv, &mad_recv_wc->recv_buf);
		if (get_last_flag(rmpp_recv->cur_seg_buf)) {
			rmpp_recv->state = RMPP_STATE_COMPLETE;
			spin_unlock_irqrestore(&rmpp_recv->lock, flags);
			done_wc = complete_rmpp(rmpp_recv);
			goto out;
		} else if (rmpp_recv->seg_num == rmpp_recv->newwin) {
			rmpp_recv->newwin += window_size(agent);
			spin_unlock_irqrestore(&rmpp_recv->lock, flags);
			ack_recv(rmpp_recv, mad_recv_wc);
			goto out;
		}
	}
	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
out:
	deref_rmpp_recv(rmpp_recv);
	return done_wc;

drop3:	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
drop2:	deref_rmpp_recv(rmpp_recv);
drop1:	ib_free_recv_mad(mad_recv_wc);
	return NULL;
}

static struct ib_mad_recv_wc *
start_rmpp(struct ib_mad_agent_private *agent,
	   struct ib_mad_recv_wc *mad_recv_wc)
{
	struct mad_rmpp_recv *rmpp_recv;
	unsigned long flags;

	rmpp_recv = create_rmpp_recv(agent, mad_recv_wc);
	if (!rmpp_recv) {
		ib_free_recv_mad(mad_recv_wc);
		return NULL;
	}

	spin_lock_irqsave(&agent->lock, flags);
	if (insert_rmpp_recv(agent, rmpp_recv)) {
		spin_unlock_irqrestore(&agent->lock, flags);
		/* duplicate first MAD */
		destroy_rmpp_recv(rmpp_recv);
		return continue_rmpp(agent, mad_recv_wc);
	}
	atomic_inc(&rmpp_recv->refcount);

	if (get_last_flag(&mad_recv_wc->recv_buf)) {
		rmpp_recv->state = RMPP_STATE_COMPLETE;
		spin_unlock_irqrestore(&agent->lock, flags);
		complete_rmpp(rmpp_recv);
	} else {
		spin_unlock_irqrestore(&agent->lock, flags);
		/* 40 seconds until we can find the packet lifetimes */
		queue_delayed_work(agent->qp_info->port_priv->wq,
				   &rmpp_recv->timeout_work,
				   msecs_to_jiffies(40000));
		rmpp_recv->newwin += window_size(agent);
		ack_recv(rmpp_recv, mad_recv_wc);
		mad_recv_wc = NULL;
	}
	deref_rmpp_recv(rmpp_recv);
	return mad_recv_wc;
}

static int send_next_seg(struct ib_mad_send_wr_private *mad_send_wr)
{
	struct ib_rmpp_mad *rmpp_mad;
	int timeout;
	u32 paylen = 0;

	rmpp_mad = mad_send_wr->send_buf.mad;
	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
	rmpp_mad->rmpp_hdr.seg_num = cpu_to_be32(++mad_send_wr->seg_num);

	if (mad_send_wr->seg_num == 1) {
		rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_FIRST;
		paylen = (mad_send_wr->send_buf.seg_count *
			  mad_send_wr->send_buf.seg_rmpp_size) -
			  mad_send_wr->pad;
	}

	if (mad_send_wr->seg_num == mad_send_wr->send_buf.seg_count) {
		rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_LAST;
		paylen = mad_send_wr->send_buf.seg_rmpp_size - mad_send_wr->pad;
	}
	rmpp_mad->rmpp_hdr.paylen_newwin = cpu_to_be32(paylen);

	/* 2 seconds for an ACK until we can find the packet lifetime */
	timeout = mad_send_wr->send_buf.timeout_ms;
	if (!timeout || timeout > 2000)
		mad_send_wr->timeout = msecs_to_jiffies(2000);

	return ib_send_mad(mad_send_wr);
}

static void abort_send(struct ib_mad_agent_private *agent,
		       struct ib_mad_recv_wc *mad_recv_wc, u8 rmpp_status)
{
	struct ib_mad_send_wr_private *mad_send_wr;
	struct ib_mad_send_wc wc;
	unsigned long flags;

	spin_lock_irqsave(&agent->lock, flags);
	mad_send_wr = ib_find_send_mad(agent, mad_recv_wc);
	if (!mad_send_wr)
		goto out;	/* Unmatched send */

	if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) ||
	    (!mad_send_wr->timeout) || (mad_send_wr->status != IB_WC_SUCCESS))
		goto out;	/* Send is already done */

	ib_mark_mad_done(mad_send_wr);
	spin_unlock_irqrestore(&agent->lock, flags);

	wc.status = IB_WC_REM_ABORT_ERR;
	wc.vendor_err = rmpp_status;
	wc.send_buf = &mad_send_wr->send_buf;
	ib_mad_complete_send_wr(mad_send_wr, &wc);
	return;
out:
	spin_unlock_irqrestore(&agent->lock, flags);
}

static inline void adjust_last_ack(struct ib_mad_send_wr_private *wr,
				   int seg_num)
{
	struct list_head *list;

	wr->last_ack = seg_num;
	list = &wr->last_ack_seg->list;
	list_for_each_entry(wr->last_ack_seg, list, list)
		if (wr->last_ack_seg->num == seg_num)
			break;
}

static void process_ds_ack(struct ib_mad_agent_private *agent,
			   struct ib_mad_recv_wc *mad_recv_wc, int newwin)
{
	struct mad_rmpp_recv *rmpp_recv;

	rmpp_recv = find_rmpp_recv(agent, mad_recv_wc);
	if (rmpp_recv && rmpp_recv->state == RMPP_STATE_COMPLETE)
		rmpp_recv->repwin = newwin;
}

static void process_rmpp_ack(struct ib_mad_agent_private *agent,
			     struct ib_mad_recv_wc *mad_recv_wc)
{
	struct ib_mad_send_wr_private *mad_send_wr;
	struct ib_rmpp_mad *rmpp_mad;
	unsigned long flags;
	int seg_num, newwin, ret;

	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
	if (rmpp_mad->rmpp_hdr.rmpp_status) {
		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
		return;
	}

	seg_num = be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
	newwin = be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
	if (newwin < seg_num) {
		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_W2S);
		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_W2S);
		return;
	}

	spin_lock_irqsave(&agent->lock, flags);
	mad_send_wr = ib_find_send_mad(agent, mad_recv_wc);
	if (!mad_send_wr) {
		if (!seg_num)
			process_ds_ack(agent, mad_recv_wc, newwin);
		goto out;	/* Unmatched or DS RMPP ACK */
	}

	if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) &&
	    (mad_send_wr->timeout)) {
		spin_unlock_irqrestore(&agent->lock, flags);
		ack_ds_ack(agent, mad_recv_wc);
		return;		/* Repeated ACK for DS RMPP transaction */
	}

	if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) ||
	    (!mad_send_wr->timeout) || (mad_send_wr->status != IB_WC_SUCCESS))
		goto out;	/* Send is already done */

	if (seg_num > mad_send_wr->send_buf.seg_count ||
	    seg_num > mad_send_wr->newwin) {
		spin_unlock_irqrestore(&agent->lock, flags);
		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_S2B);
		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_S2B);
		return;
	}

	if (newwin < mad_send_wr->newwin || seg_num < mad_send_wr->last_ack)
		goto out;	/* Old ACK */

	if (seg_num > mad_send_wr->last_ack) {
		adjust_last_ack(mad_send_wr, seg_num);
		mad_send_wr->retries_left = mad_send_wr->max_retries;
	}
	mad_send_wr->newwin = newwin;
	if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) {
		/* If no response is expected, the ACK completes the send */
		if (!mad_send_wr->send_buf.timeout_ms) {
			struct ib_mad_send_wc wc;

			ib_mark_mad_done(mad_send_wr);
			spin_unlock_irqrestore(&agent->lock, flags);

			wc.status = IB_WC_SUCCESS;
			wc.vendor_err = 0;
			wc.send_buf = &mad_send_wr->send_buf;
			ib_mad_complete_send_wr(mad_send_wr, &wc);
			return;
		}
		if (mad_send_wr->refcount == 1)
			ib_reset_mad_timeout(mad_send_wr,
					     mad_send_wr->send_buf.timeout_ms);
		spin_unlock_irqrestore(&agent->lock, flags);
		ack_ds_ack(agent, mad_recv_wc);
		return;
	} else if (mad_send_wr->refcount == 1 &&
		   mad_send_wr->seg_num < mad_send_wr->newwin &&
		   mad_send_wr->seg_num < mad_send_wr->send_buf.seg_count) {
		/* Send failure will just result in a timeout/retry */
		ret = send_next_seg(mad_send_wr);
		if (ret)
			goto out;

		mad_send_wr->refcount++;
		list_move_tail(&mad_send_wr->agent_list,
			      &mad_send_wr->mad_agent_priv->send_list);
	}
out:
	spin_unlock_irqrestore(&agent->lock, flags);
}

static struct ib_mad_recv_wc *
process_rmpp_data(struct ib_mad_agent_private *agent,
		  struct ib_mad_recv_wc *mad_recv_wc)
{
	struct ib_rmpp_hdr *rmpp_hdr;
	u8 rmpp_status;

	rmpp_hdr = &((struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad)->rmpp_hdr;

	if (rmpp_hdr->rmpp_status) {
		rmpp_status = IB_MGMT_RMPP_STATUS_BAD_STATUS;
		goto bad;
	}

	if (rmpp_hdr->seg_num == cpu_to_be32(1)) {
		if (!(ib_get_rmpp_flags(rmpp_hdr) & IB_MGMT_RMPP_FLAG_FIRST)) {
			rmpp_status = IB_MGMT_RMPP_STATUS_BAD_SEG;
			goto bad;
		}
		return start_rmpp(agent, mad_recv_wc);
	} else {
		if (ib_get_rmpp_flags(rmpp_hdr) & IB_MGMT_RMPP_FLAG_FIRST) {
			rmpp_status = IB_MGMT_RMPP_STATUS_BAD_SEG;
			goto bad;
		}
		return continue_rmpp(agent, mad_recv_wc);
	}
bad:
	nack_recv(agent, mad_recv_wc, rmpp_status);
	ib_free_recv_mad(mad_recv_wc);
	return NULL;
}

static void process_rmpp_stop(struct ib_mad_agent_private *agent,
			      struct ib_mad_recv_wc *mad_recv_wc)
{
	struct ib_rmpp_mad *rmpp_mad;

	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;

	if (rmpp_mad->rmpp_hdr.rmpp_status != IB_MGMT_RMPP_STATUS_RESX) {
		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
	} else
		abort_send(agent, mad_recv_wc, rmpp_mad->rmpp_hdr.rmpp_status);
}

static void process_rmpp_abort(struct ib_mad_agent_private *agent,
			       struct ib_mad_recv_wc *mad_recv_wc)
{
	struct ib_rmpp_mad *rmpp_mad;

	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;

	if (rmpp_mad->rmpp_hdr.rmpp_status < IB_MGMT_RMPP_STATUS_ABORT_MIN ||
	    rmpp_mad->rmpp_hdr.rmpp_status > IB_MGMT_RMPP_STATUS_ABORT_MAX) {
		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
	} else
		abort_send(agent, mad_recv_wc, rmpp_mad->rmpp_hdr.rmpp_status);
}

struct ib_mad_recv_wc *
ib_process_rmpp_recv_wc(struct ib_mad_agent_private *agent,
			struct ib_mad_recv_wc *mad_recv_wc)
{
	struct ib_rmpp_mad *rmpp_mad;

	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
	if (!(rmpp_mad->rmpp_hdr.rmpp_rtime_flags & IB_MGMT_RMPP_FLAG_ACTIVE))
		return mad_recv_wc;

	if (rmpp_mad->rmpp_hdr.rmpp_version != IB_MGMT_RMPP_VERSION) {
		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_UNV);
		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_UNV);
		goto out;
	}

	switch (rmpp_mad->rmpp_hdr.rmpp_type) {
	case IB_MGMT_RMPP_TYPE_DATA:
		return process_rmpp_data(agent, mad_recv_wc);
	case IB_MGMT_RMPP_TYPE_ACK:
		process_rmpp_ack(agent, mad_recv_wc);
		break;
	case IB_MGMT_RMPP_TYPE_STOP:
		process_rmpp_stop(agent, mad_recv_wc);
		break;
	case IB_MGMT_RMPP_TYPE_ABORT:
		process_rmpp_abort(agent, mad_recv_wc);
		break;
	default:
		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BADT);
		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BADT);
		break;
	}
out:
	ib_free_recv_mad(mad_recv_wc);
	return NULL;
}

static int init_newwin(struct ib_mad_send_wr_private *mad_send_wr)
{
	struct ib_mad_agent_private *agent = mad_send_wr->mad_agent_priv;
	struct ib_mad_hdr *mad_hdr = mad_send_wr->send_buf.mad;
	struct mad_rmpp_recv *rmpp_recv;
	struct ib_ah_attr ah_attr;
	unsigned long flags;
	int newwin = 1;

	if (!(mad_hdr->method & IB_MGMT_METHOD_RESP))
		goto out;

	spin_lock_irqsave(&agent->lock, flags);
	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
		if (rmpp_recv->tid != mad_hdr->tid ||
		    rmpp_recv->mgmt_class != mad_hdr->mgmt_class ||
		    rmpp_recv->class_version != mad_hdr->class_version ||
		    (rmpp_recv->method & IB_MGMT_METHOD_RESP))
			continue;

		if (ib_query_ah(mad_send_wr->send_buf.ah, &ah_attr))
			continue;

		if (rmpp_recv->slid == ah_attr.dlid) {
			newwin = rmpp_recv->repwin;
			break;
		}
	}
	spin_unlock_irqrestore(&agent->lock, flags);
out:
	return newwin;
}

int ib_send_rmpp_mad(struct ib_mad_send_wr_private *mad_send_wr)
{
	struct ib_rmpp_mad *rmpp_mad;
	int ret;

	rmpp_mad = mad_send_wr->send_buf.mad;
	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
	      IB_MGMT_RMPP_FLAG_ACTIVE))
		return IB_RMPP_RESULT_UNHANDLED;

	if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA) {
		mad_send_wr->seg_num = 1;
		return IB_RMPP_RESULT_INTERNAL;
	}

	mad_send_wr->newwin = init_newwin(mad_send_wr);

	/* We need to wait for the final ACK even if there isn't a response */
	mad_send_wr->refcount += (mad_send_wr->timeout == 0);
	ret = send_next_seg(mad_send_wr);
	if (!ret)
		return IB_RMPP_RESULT_CONSUMED;
	return ret;
}

int ib_process_rmpp_send_wc(struct ib_mad_send_wr_private *mad_send_wr,
			    struct ib_mad_send_wc *mad_send_wc)
{
	struct ib_rmpp_mad *rmpp_mad;
	int ret;

	rmpp_mad = mad_send_wr->send_buf.mad;
	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
	      IB_MGMT_RMPP_FLAG_ACTIVE))
		return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */

	if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA)
		return IB_RMPP_RESULT_INTERNAL;	 /* ACK, STOP, or ABORT */

	if (mad_send_wc->status != IB_WC_SUCCESS ||
	    mad_send_wr->status != IB_WC_SUCCESS)
		return IB_RMPP_RESULT_PROCESSED; /* Canceled or send error */

	if (!mad_send_wr->timeout)
		return IB_RMPP_RESULT_PROCESSED; /* Response received */

	if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) {
		mad_send_wr->timeout =
			msecs_to_jiffies(mad_send_wr->send_buf.timeout_ms);
		return IB_RMPP_RESULT_PROCESSED; /* Send done */
	}

	if (mad_send_wr->seg_num == mad_send_wr->newwin ||
	    mad_send_wr->seg_num == mad_send_wr->send_buf.seg_count)
		return IB_RMPP_RESULT_PROCESSED; /* Wait for ACK */

	ret = send_next_seg(mad_send_wr);
	if (ret) {
		mad_send_wc->status = IB_WC_GENERAL_ERR;
		return IB_RMPP_RESULT_PROCESSED;
	}
	return IB_RMPP_RESULT_CONSUMED;
}

int ib_retry_rmpp(struct ib_mad_send_wr_private *mad_send_wr)
{
	struct ib_rmpp_mad *rmpp_mad;
	int ret;

	rmpp_mad = mad_send_wr->send_buf.mad;
	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
	      IB_MGMT_RMPP_FLAG_ACTIVE))
		return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */

	if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count)
		return IB_RMPP_RESULT_PROCESSED;

	mad_send_wr->seg_num = mad_send_wr->last_ack;
	mad_send_wr->cur_seg = mad_send_wr->last_ack_seg;

	ret = send_next_seg(mad_send_wr);
	if (ret)
		return IB_RMPP_RESULT_PROCESSED;

	return IB_RMPP_RESULT_CONSUMED;
}