summaryrefslogtreecommitdiffstats
path: root/drivers/infiniband/core/sa_query.c
blob: 9ef8fe0163dd8189364fe37a6e2a3ef2fc2ee0aa (plain) (blame)
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
/*
 * Copyright (c) 2004 Topspin Communications.  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.
 *
 * $Id: sa_query.c 1389 2004-12-27 22:56:47Z roland $
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/random.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/kref.h>
#include <linux/idr.h>

#include <ib_pack.h>
#include <ib_sa.h>

MODULE_AUTHOR("Roland Dreier");
MODULE_DESCRIPTION("InfiniBand subnet administration query support");
MODULE_LICENSE("Dual BSD/GPL");

/*
 * These two structures must be packed because they have 64-bit fields
 * that are only 32-bit aligned.  64-bit architectures will lay them
 * out wrong otherwise.  (And unfortunately they are sent on the wire
 * so we can't change the layout)
 */
struct ib_sa_hdr {
	u64			sm_key;
	u16			attr_offset;
	u16			reserved;
	ib_sa_comp_mask		comp_mask;
} __attribute__ ((packed));

struct ib_sa_mad {
	struct ib_mad_hdr	mad_hdr;
	struct ib_rmpp_hdr	rmpp_hdr;
	struct ib_sa_hdr	sa_hdr;
	u8			data[200];
} __attribute__ ((packed));

struct ib_sa_sm_ah {
	struct ib_ah        *ah;
	struct kref          ref;
};

struct ib_sa_port {
	struct ib_mad_agent *agent;
	struct ib_sa_sm_ah  *sm_ah;
	struct work_struct   update_task;
	spinlock_t           ah_lock;
	u8                   port_num;
};

struct ib_sa_device {
	int                     start_port, end_port;
	struct ib_event_handler event_handler;
	struct ib_sa_port port[0];
};

struct ib_sa_query {
	void (*callback)(struct ib_sa_query *, int, struct ib_sa_mad *);
	void (*release)(struct ib_sa_query *);
	struct ib_sa_port  *port;
	struct ib_sa_mad   *mad;
	struct ib_sa_sm_ah *sm_ah;
	DECLARE_PCI_UNMAP_ADDR(mapping)
	int                 id;
};

struct ib_sa_path_query {
	void (*callback)(int, struct ib_sa_path_rec *, void *);
	void *context;
	struct ib_sa_query sa_query;
};

struct ib_sa_mcmember_query {
	void (*callback)(int, struct ib_sa_mcmember_rec *, void *);
	void *context;
	struct ib_sa_query sa_query;
};

static void ib_sa_add_one(struct ib_device *device);
static void ib_sa_remove_one(struct ib_device *device);

static struct ib_client sa_client = {
	.name   = "sa",
	.add    = ib_sa_add_one,
	.remove = ib_sa_remove_one
};

static spinlock_t idr_lock;
static DEFINE_IDR(query_idr);

static spinlock_t tid_lock;
static u32 tid;

enum {
	IB_SA_ATTR_CLASS_PORTINFO    = 0x01,
	IB_SA_ATTR_NOTICE	     = 0x02,
	IB_SA_ATTR_INFORM_INFO	     = 0x03,
	IB_SA_ATTR_NODE_REC	     = 0x11,
	IB_SA_ATTR_PORT_INFO_REC     = 0x12,
	IB_SA_ATTR_SL2VL_REC	     = 0x13,
	IB_SA_ATTR_SWITCH_REC	     = 0x14,
	IB_SA_ATTR_LINEAR_FDB_REC    = 0x15,
	IB_SA_ATTR_RANDOM_FDB_REC    = 0x16,
	IB_SA_ATTR_MCAST_FDB_REC     = 0x17,
	IB_SA_ATTR_SM_INFO_REC	     = 0x18,
	IB_SA_ATTR_LINK_REC	     = 0x20,
	IB_SA_ATTR_GUID_INFO_REC     = 0x30,
	IB_SA_ATTR_SERVICE_REC	     = 0x31,
	IB_SA_ATTR_PARTITION_REC     = 0x33,
	IB_SA_ATTR_RANGE_REC	     = 0x34,
	IB_SA_ATTR_PATH_REC	     = 0x35,
	IB_SA_ATTR_VL_ARB_REC	     = 0x36,
	IB_SA_ATTR_MC_GROUP_REC	     = 0x37,
	IB_SA_ATTR_MC_MEMBER_REC     = 0x38,
	IB_SA_ATTR_TRACE_REC	     = 0x39,
	IB_SA_ATTR_MULTI_PATH_REC    = 0x3a,
	IB_SA_ATTR_SERVICE_ASSOC_REC = 0x3b
};

#define PATH_REC_FIELD(field) \
	.struct_offset_bytes = offsetof(struct ib_sa_path_rec, field),		\
	.struct_size_bytes   = sizeof ((struct ib_sa_path_rec *) 0)->field,	\
	.field_name          = "sa_path_rec:" #field

static const struct ib_field path_rec_table[] = {
	{ RESERVED,
	  .offset_words = 0,
	  .offset_bits  = 0,
	  .size_bits    = 32 },
	{ RESERVED,
	  .offset_words = 1,
	  .offset_bits  = 0,
	  .size_bits    = 32 },
	{ PATH_REC_FIELD(dgid),
	  .offset_words = 2,
	  .offset_bits  = 0,
	  .size_bits    = 128 },
	{ PATH_REC_FIELD(sgid),
	  .offset_words = 6,
	  .offset_bits  = 0,
	  .size_bits    = 128 },
	{ PATH_REC_FIELD(dlid),
	  .offset_words = 10,
	  .offset_bits  = 0,
	  .size_bits    = 16 },
	{ PATH_REC_FIELD(slid),
	  .offset_words = 10,
	  .offset_bits  = 16,
	  .size_bits    = 16 },
	{ PATH_REC_FIELD(raw_traffic),
	  .offset_words = 11,
	  .offset_bits  = 0,
	  .size_bits    = 1 },
	{ RESERVED,
	  .offset_words = 11,
	  .offset_bits  = 1,
	  .size_bits    = 3 },
	{ PATH_REC_FIELD(flow_label),
	  .offset_words = 11,
	  .offset_bits  = 4,
	  .size_bits    = 20 },
	{ PATH_REC_FIELD(hop_limit),
	  .offset_words = 11,
	  .offset_bits  = 24,
	  .size_bits    = 8 },
	{ PATH_REC_FIELD(traffic_class),
	  .offset_words = 12,
	  .offset_bits  = 0,
	  .size_bits    = 8 },
	{ PATH_REC_FIELD(reversible),
	  .offset_words = 12,
	  .offset_bits  = 8,
	  .size_bits    = 1 },
	{ PATH_REC_FIELD(numb_path),
	  .offset_words = 12,
	  .offset_bits  = 9,
	  .size_bits    = 7 },
	{ PATH_REC_FIELD(pkey),
	  .offset_words = 12,
	  .offset_bits  = 16,
	  .size_bits    = 16 },
	{ RESERVED,
	  .offset_words = 13,
	  .offset_bits  = 0,
	  .size_bits    = 12 },
	{ PATH_REC_FIELD(sl),
	  .offset_words = 13,
	  .offset_bits  = 12,
	  .size_bits    = 4 },
	{ PATH_REC_FIELD(mtu_selector),
	  .offset_words = 13,
	  .offset_bits  = 16,
	  .size_bits    = 2 },
	{ PATH_REC_FIELD(mtu),
	  .offset_words = 13,
	  .offset_bits  = 18,
	  .size_bits    = 6 },
	{ PATH_REC_FIELD(rate_selector),
	  .offset_words = 13,
	  .offset_bits  = 24,
	  .size_bits    = 2 },
	{ PATH_REC_FIELD(rate),
	  .offset_words = 13,
	  .offset_bits  = 26,
	  .size_bits    = 6 },
	{ PATH_REC_FIELD(packet_life_time_selector),
	  .offset_words = 14,
	  .offset_bits  = 0,
	  .size_bits    = 2 },
	{ PATH_REC_FIELD(packet_life_time),
	  .offset_words = 14,
	  .offset_bits  = 2,
	  .size_bits    = 6 },
	{ PATH_REC_FIELD(preference),
	  .offset_words = 14,
	  .offset_bits  = 8,
	  .size_bits    = 8 },
	{ RESERVED,
	  .offset_words = 14,
	  .offset_bits  = 16,
	  .size_bits    = 48 },
};

#define MCMEMBER_REC_FIELD(field) \
	.struct_offset_bytes = offsetof(struct ib_sa_mcmember_rec, field),	\
	.struct_size_bytes   = sizeof ((struct ib_sa_mcmember_rec *) 0)->field,	\
	.field_name          = "sa_mcmember_rec:" #field

static const struct ib_field mcmember_rec_table[] = {
	{ MCMEMBER_REC_FIELD(mgid),
	  .offset_words = 0,
	  .offset_bits  = 0,
	  .size_bits    = 128 },
	{ MCMEMBER_REC_FIELD(port_gid),
	  .offset_words = 4,
	  .offset_bits  = 0,
	  .size_bits    = 128 },
	{ MCMEMBER_REC_FIELD(qkey),
	  .offset_words = 8,
	  .offset_bits  = 0,
	  .size_bits    = 32 },
	{ MCMEMBER_REC_FIELD(mlid),
	  .offset_words = 9,
	  .offset_bits  = 0,
	  .size_bits    = 16 },
	{ MCMEMBER_REC_FIELD(mtu_selector),
	  .offset_words = 9,
	  .offset_bits  = 16,
	  .size_bits    = 2 },
	{ MCMEMBER_REC_FIELD(mtu),
	  .offset_words = 9,
	  .offset_bits  = 18,
	  .size_bits    = 6 },
	{ MCMEMBER_REC_FIELD(traffic_class),
	  .offset_words = 9,
	  .offset_bits  = 24,
	  .size_bits    = 8 },
	{ MCMEMBER_REC_FIELD(pkey),
	  .offset_words = 10,
	  .offset_bits  = 0,
	  .size_bits    = 16 },
	{ MCMEMBER_REC_FIELD(rate_selector),
	  .offset_words = 10,
	  .offset_bits  = 16,
	  .size_bits    = 2 },
	{ MCMEMBER_REC_FIELD(rate),
	  .offset_words = 10,
	  .offset_bits  = 18,
	  .size_bits    = 6 },
	{ MCMEMBER_REC_FIELD(packet_life_time_selector),
	  .offset_words = 10,
	  .offset_bits  = 24,
	  .size_bits    = 2 },
	{ MCMEMBER_REC_FIELD(packet_life_time),
	  .offset_words = 10,
	  .offset_bits  = 26,
	  .size_bits    = 6 },
	{ MCMEMBER_REC_FIELD(sl),
	  .offset_words = 11,
	  .offset_bits  = 0,
	  .size_bits    = 4 },
	{ MCMEMBER_REC_FIELD(flow_label),
	  .offset_words = 11,
	  .offset_bits  = 4,
	  .size_bits    = 20 },
	{ MCMEMBER_REC_FIELD(hop_limit),
	  .offset_words = 11,
	  .offset_bits  = 24,
	  .size_bits    = 8 },
	{ MCMEMBER_REC_FIELD(scope),
	  .offset_words = 12,
	  .offset_bits  = 0,
	  .size_bits    = 4 },
	{ MCMEMBER_REC_FIELD(join_state),
	  .offset_words = 12,
	  .offset_bits  = 4,
	  .size_bits    = 4 },
	{ MCMEMBER_REC_FIELD(proxy_join),
	  .offset_words = 12,
	  .offset_bits  = 8,
	  .size_bits    = 1 },
	{ RESERVED,
	  .offset_words = 12,
	  .offset_bits  = 9,
	  .size_bits    = 23 },
};

static void free_sm_ah(struct kref *kref)
{
	struct ib_sa_sm_ah *sm_ah = container_of(kref, struct ib_sa_sm_ah, ref);

	ib_destroy_ah(sm_ah->ah);
	kfree(sm_ah);
}

static void update_sm_ah(void *port_ptr)
{
	struct ib_sa_port *port = port_ptr;
	struct ib_sa_sm_ah *new_ah, *old_ah;
	struct ib_port_attr port_attr;
	struct ib_ah_attr   ah_attr;

	if (ib_query_port(port->agent->device, port->port_num, &port_attr)) {
		printk(KERN_WARNING "Couldn't query port\n");
		return;
	}

	new_ah = kmalloc(sizeof *new_ah, GFP_KERNEL);
	if (!new_ah) {
		printk(KERN_WARNING "Couldn't allocate new SM AH\n");
		return;
	}

	kref_init(&new_ah->ref);

	memset(&ah_attr, 0, sizeof ah_attr);
	ah_attr.dlid     = port_attr.sm_lid;
	ah_attr.sl       = port_attr.sm_sl;
	ah_attr.port_num = port->port_num;

	new_ah->ah = ib_create_ah(port->agent->qp->pd, &ah_attr);
	if (IS_ERR(new_ah->ah)) {
		printk(KERN_WARNING "Couldn't create new SM AH\n");
		kfree(new_ah);
		return;
	}

	spin_lock_irq(&port->ah_lock);
	old_ah = port->sm_ah;
	port->sm_ah = new_ah;
	spin_unlock_irq(&port->ah_lock);

	if (old_ah)
		kref_put(&old_ah->ref, free_sm_ah);
}

static void ib_sa_event(struct ib_event_handler *handler, struct ib_event *event)
{
	if (event->event == IB_EVENT_PORT_ERR    ||
	    event->event == IB_EVENT_PORT_ACTIVE ||
	    event->event == IB_EVENT_LID_CHANGE  ||
	    event->event == IB_EVENT_PKEY_CHANGE ||
	    event->event == IB_EVENT_SM_CHANGE) {
		struct ib_sa_device *sa_dev =
			ib_get_client_data(event->device, &sa_client);

		schedule_work(&sa_dev->port[event->element.port_num -
					    sa_dev->start_port].update_task);
	}
}

/**
 * ib_sa_cancel_query - try to cancel an SA query
 * @id:ID of query to cancel
 * @query:query pointer to cancel
 *
 * Try to cancel an SA query.  If the id and query don't match up or
 * the query has already completed, nothing is done.  Otherwise the
 * query is canceled and will complete with a status of -EINTR.
 */
void ib_sa_cancel_query(int id, struct ib_sa_query *query)
{
	unsigned long flags;
	struct ib_mad_agent *agent;

	spin_lock_irqsave(&idr_lock, flags);
	if (idr_find(&query_idr, id) != query) {
		spin_unlock_irqrestore(&idr_lock, flags);
		return;
	}
	agent = query->port->agent;
	spin_unlock_irqrestore(&idr_lock, flags);

	ib_cancel_mad(agent, id);
}
EXPORT_SYMBOL(ib_sa_cancel_query);

static void init_mad(struct ib_sa_mad *mad, struct ib_mad_agent *agent)
{
	unsigned long flags;

	memset(mad, 0, sizeof *mad);

	mad->mad_hdr.base_version  = IB_MGMT_BASE_VERSION;
	mad->mad_hdr.mgmt_class    = IB_MGMT_CLASS_SUBN_ADM;
	mad->mad_hdr.class_version = IB_SA_CLASS_VERSION;

	spin_lock_irqsave(&tid_lock, flags);
	mad->mad_hdr.tid           =
		cpu_to_be64(((u64) agent->hi_tid) << 32 | tid++);
	spin_unlock_irqrestore(&tid_lock, flags);
}

static int send_mad(struct ib_sa_query *query, int timeout_ms)
{
	struct ib_sa_port *port = query->port;
	unsigned long flags;
	int ret;
	struct ib_sge      gather_list;
	struct ib_send_wr *bad_wr, wr = {
		.opcode      = IB_WR_SEND,
		.sg_list     = &gather_list,
		.num_sge     = 1,
		.send_flags  = IB_SEND_SIGNALED,
		.wr	     = {
			 .ud = {
				 .mad_hdr     = &query->mad->mad_hdr,
				 .remote_qpn  = 1,
				 .remote_qkey = IB_QP1_QKEY,
				 .timeout_ms  = timeout_ms,
				 .retries     = 0
			 }
		 }
	};

retry:
	if (!idr_pre_get(&query_idr, GFP_ATOMIC))
		return -ENOMEM;
	spin_lock_irqsave(&idr_lock, flags);
	ret = idr_get_new(&query_idr, query, &query->id);
	spin_unlock_irqrestore(&idr_lock, flags);
	if (ret == -EAGAIN)
		goto retry;
	if (ret)
		return ret;

	wr.wr_id = query->id;

	spin_lock_irqsave(&port->ah_lock, flags);
	kref_get(&port->sm_ah->ref);
	query->sm_ah = port->sm_ah;
	wr.wr.ud.ah  = port->sm_ah->ah;
	spin_unlock_irqrestore(&port->ah_lock, flags);

	gather_list.addr   = dma_map_single(port->agent->device->dma_device,
					    query->mad,
					    sizeof (struct ib_sa_mad),
					    DMA_TO_DEVICE);
	gather_list.length = sizeof (struct ib_sa_mad);
	gather_list.lkey   = port->agent->mr->lkey;
	pci_unmap_addr_set(query, mapping, gather_list.addr);

	ret = ib_post_send_mad(port->agent, &wr, &bad_wr);
	if (ret) {
		dma_unmap_single(port->agent->device->dma_device,
				 pci_unmap_addr(query, mapping),
				 sizeof (struct ib_sa_mad),
				 DMA_TO_DEVICE);
		kref_put(&query->sm_ah->ref, free_sm_ah);
		spin_lock_irqsave(&idr_lock, flags);
		idr_remove(&query_idr, query->id);
		spin_unlock_irqrestore(&idr_lock, flags);
	}

	/*
	 * It's not safe to dereference query any more, because the
	 * send may already have completed and freed the query in
	 * another context.  So use wr.wr_id, which has a copy of the
	 * query's id.
	 */
	return ret ? ret : wr.wr_id;
}

static void ib_sa_path_rec_callback(struct ib_sa_query *sa_query,
				    int status,
				    struct ib_sa_mad *mad)
{
	struct ib_sa_path_query *query =
		container_of(sa_query, struct ib_sa_path_query, sa_query);

	if (mad) {
		struct ib_sa_path_rec rec;

		ib_unpack(path_rec_table, ARRAY_SIZE(path_rec_table),
			  mad->data, &rec);
		query->callback(status, &rec, query->context);
	} else
		query->callback(status, NULL, query->context);
}

static void ib_sa_path_rec_release(struct ib_sa_query *sa_query)
{
	kfree(sa_query->mad);
	kfree(container_of(sa_query, struct ib_sa_path_query, sa_query));
}

/**
 * ib_sa_path_rec_get - Start a Path get query
 * @device:device to send query on
 * @port_num: port number to send query on
 * @rec:Path Record to send in query
 * @comp_mask:component mask to send in query
 * @timeout_ms:time to wait for response
 * @gfp_mask:GFP mask to use for internal allocations
 * @callback:function called when query completes, times out or is
 * canceled
 * @context:opaque user context passed to callback
 * @sa_query:query context, used to cancel query
 *
 * Send a Path Record Get query to the SA to look up a path.  The
 * callback function will be called when the query completes (or
 * fails); status is 0 for a successful response, -EINTR if the query
 * is canceled, -ETIMEDOUT is the query timed out, or -EIO if an error
 * occurred sending the query.  The resp parameter of the callback is
 * only valid if status is 0.
 *
 * If the return value of ib_sa_path_rec_get() is negative, it is an
 * error code.  Otherwise it is a query ID that can be used to cancel
 * the query.
 */
int ib_sa_path_rec_get(struct ib_device *device, u8 port_num,
		       struct ib_sa_path_rec *rec,
		       ib_sa_comp_mask comp_mask,
		       int timeout_ms, int gfp_mask,
		       void (*callback)(int status,
					struct ib_sa_path_rec *resp,
					void *context),
		       void *context,
		       struct ib_sa_query **sa_query)
{
	struct ib_sa_path_query *query;
	struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
	struct ib_sa_port   *port   = &sa_dev->port[port_num - sa_dev->start_port];
	struct ib_mad_agent *agent  = port->agent;
	int ret;

	query = kmalloc(sizeof *query, gfp_mask);
	if (!query)
		return -ENOMEM;
	query->sa_query.mad = kmalloc(sizeof *query->sa_query.mad, gfp_mask);
	if (!query->sa_query.mad) {
		kfree(query);
		return -ENOMEM;
	}

	query->callback = callback;
	query->context  = context;

	init_mad(query->sa_query.mad, agent);

	query->sa_query.callback              = callback ? ib_sa_path_rec_callback : NULL;
	query->sa_query.release               = ib_sa_path_rec_release;
	query->sa_query.port                  = port;
	query->sa_query.mad->mad_hdr.method   = IB_MGMT_METHOD_GET;
	query->sa_query.mad->mad_hdr.attr_id  = cpu_to_be16(IB_SA_ATTR_PATH_REC);
	query->sa_query.mad->sa_hdr.comp_mask = comp_mask;

	ib_pack(path_rec_table, ARRAY_SIZE(path_rec_table),
		rec, query->sa_query.mad->data);

	*sa_query = &query->sa_query;

	ret = send_mad(&query->sa_query, timeout_ms);
	if (ret < 0) {
		*sa_query = NULL;
		kfree(query->sa_query.mad);
		kfree(query);
	}

	return ret;
}
EXPORT_SYMBOL(ib_sa_path_rec_get);

static void ib_sa_mcmember_rec_callback(struct ib_sa_query *sa_query,
					int status,
					struct ib_sa_mad *mad)
{
	struct ib_sa_mcmember_query *query =
		container_of(sa_query, struct ib_sa_mcmember_query, sa_query);

	if (mad) {
		struct ib_sa_mcmember_rec rec;

		ib_unpack(mcmember_rec_table, ARRAY_SIZE(mcmember_rec_table),
			  mad->data, &rec);
		query->callback(status, &rec, query->context);
	} else
		query->callback(status, NULL, query->context);
}

static void ib_sa_mcmember_rec_release(struct ib_sa_query *sa_query)
{
	kfree(sa_query->mad);
	kfree(container_of(sa_query, struct ib_sa_mcmember_query, sa_query));
}

int ib_sa_mcmember_rec_query(struct ib_device *device, u8 port_num,
			     u8 method,
			     struct ib_sa_mcmember_rec *rec,
			     ib_sa_comp_mask comp_mask,
			     int timeout_ms, int gfp_mask,
			     void (*callback)(int status,
					      struct ib_sa_mcmember_rec *resp,
					      void *context),
			     void *context,
			     struct ib_sa_query **sa_query)
{
	struct ib_sa_mcmember_query *query;
	struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
	struct ib_sa_port   *port   = &sa_dev->port[port_num - sa_dev->start_port];
	struct ib_mad_agent *agent  = port->agent;
	int ret;

	query = kmalloc(sizeof *query, gfp_mask);
	if (!query)
		return -ENOMEM;
	query->sa_query.mad = kmalloc(sizeof *query->sa_query.mad, gfp_mask);
	if (!query->sa_query.mad) {
		kfree(query);
		return -ENOMEM;
	}

	query->callback = callback;
	query->context  = context;

	init_mad(query->sa_query.mad, agent);

	query->sa_query.callback              = callback ? ib_sa_mcmember_rec_callback : NULL;
	query->sa_query.release               = ib_sa_mcmember_rec_release;
	query->sa_query.port                  = port;
	query->sa_query.mad->mad_hdr.method   = method;
	query->sa_query.mad->mad_hdr.attr_id  = cpu_to_be16(IB_SA_ATTR_MC_MEMBER_REC);
	query->sa_query.mad->sa_hdr.comp_mask = comp_mask;

	ib_pack(mcmember_rec_table, ARRAY_SIZE(mcmember_rec_table),
		rec, query->sa_query.mad->data);

	*sa_query = &query->sa_query;

	ret = send_mad(&query->sa_query, timeout_ms);
	if (ret < 0) {
		*sa_query = NULL;
		kfree(query->sa_query.mad);
		kfree(query);
	}

	return ret;
}
EXPORT_SYMBOL(ib_sa_mcmember_rec_query);

static void send_handler(struct ib_mad_agent *agent,
			 struct ib_mad_send_wc *mad_send_wc)
{
	struct ib_sa_query *query;
	unsigned long flags;

	spin_lock_irqsave(&idr_lock, flags);
	query = idr_find(&query_idr, mad_send_wc->wr_id);
	spin_unlock_irqrestore(&idr_lock, flags);

	if (!query)
		return;

	if (query->callback)
		switch (mad_send_wc->status) {
		case IB_WC_SUCCESS:
			/* No callback -- already got recv */
			break;
		case IB_WC_RESP_TIMEOUT_ERR:
			query->callback(query, -ETIMEDOUT, NULL);
			break;
		case IB_WC_WR_FLUSH_ERR:
			query->callback(query, -EINTR, NULL);
			break;
		default:
			query->callback(query, -EIO, NULL);
			break;
		}

	dma_unmap_single(agent->device->dma_device,
			 pci_unmap_addr(query, mapping),
			 sizeof (struct ib_sa_mad),
			 DMA_TO_DEVICE);
	kref_put(&query->sm_ah->ref, free_sm_ah);

	query->release(query);

	spin_lock_irqsave(&idr_lock, flags);
	idr_remove(&query_idr, mad_send_wc->wr_id);
	spin_unlock_irqrestore(&idr_lock, flags);
}

static void recv_handler(struct ib_mad_agent *mad_agent,
			 struct ib_mad_recv_wc *mad_recv_wc)
{
	struct ib_sa_query *query;
	unsigned long flags;

	spin_lock_irqsave(&idr_lock, flags);
	query = idr_find(&query_idr, mad_recv_wc->wc->wr_id);
	spin_unlock_irqrestore(&idr_lock, flags);

	if (query && query->callback) {
		if (mad_recv_wc->wc->status == IB_WC_SUCCESS)
			query->callback(query,
					mad_recv_wc->recv_buf.mad->mad_hdr.status ?
					-EINVAL : 0,
					(struct ib_sa_mad *) mad_recv_wc->recv_buf.mad);
		else
			query->callback(query, -EIO, NULL);
	}

	ib_free_recv_mad(mad_recv_wc);
}

static void ib_sa_add_one(struct ib_device *device)
{
	struct ib_sa_device *sa_dev;
	int s, e, i;

	if (device->node_type == IB_NODE_SWITCH)
		s = e = 0;
	else {
		s = 1;
		e = device->phys_port_cnt;
	}

	sa_dev = kmalloc(sizeof *sa_dev +
			 (e - s + 1) * sizeof (struct ib_sa_port),
			 GFP_KERNEL);
	if (!sa_dev)
		return;

	sa_dev->start_port = s;
	sa_dev->end_port   = e;

	for (i = 0; i <= e - s; ++i) {
		sa_dev->port[i].sm_ah    = NULL;
		sa_dev->port[i].port_num = i + s;
		spin_lock_init(&sa_dev->port[i].ah_lock);

		sa_dev->port[i].agent =
			ib_register_mad_agent(device, i + s, IB_QPT_GSI,
					      NULL, 0, send_handler,
					      recv_handler, sa_dev);
		if (IS_ERR(sa_dev->port[i].agent))
			goto err;

		INIT_WORK(&sa_dev->port[i].update_task,
			  update_sm_ah, &sa_dev->port[i]);
	}

	ib_set_client_data(device, &sa_client, sa_dev);

	/*
	 * We register our event handler after everything is set up,
	 * and then update our cached info after the event handler is
	 * registered to avoid any problems if a port changes state
	 * during our initialization.
	 */

	INIT_IB_EVENT_HANDLER(&sa_dev->event_handler, device, ib_sa_event);
	if (ib_register_event_handler(&sa_dev->event_handler))
		goto err;

	for (i = 0; i <= e - s; ++i)
		update_sm_ah(&sa_dev->port[i]);

	return;

err:
	while (--i >= 0)
		ib_unregister_mad_agent(sa_dev->port[i].agent);

	kfree(sa_dev);

	return;
}

static void ib_sa_remove_one(struct ib_device *device)
{
	struct ib_sa_device *sa_dev = ib_get_client_data(device, &sa_client);
	int i;

	if (!sa_dev)
		return;

	ib_unregister_event_handler(&sa_dev->event_handler);

	for (i = 0; i <= sa_dev->end_port - sa_dev->start_port; ++i) {
		ib_unregister_mad_agent(sa_dev->port[i].agent);
		kref_put(&sa_dev->port[i].sm_ah->ref, free_sm_ah);
	}

	kfree(sa_dev);
}

static int __init ib_sa_init(void)
{
	int ret;

	spin_lock_init(&idr_lock);
	spin_lock_init(&tid_lock);

	get_random_bytes(&tid, sizeof tid);

	ret = ib_register_client(&sa_client);
	if (ret)
		printk(KERN_ERR "Couldn't register ib_sa client\n");

	return ret;
}

static void __exit ib_sa_cleanup(void)
{
	ib_unregister_client(&sa_client);
}

module_init(ib_sa_init);
module_exit(ib_sa_cleanup);