summaryrefslogtreecommitdiff
path: root/drivers/infiniband/core/iwpm_util.c
blob: cdb63f3f4de70ac57c0eb761a3bbef42b017f6f4 (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
/*
 * Copyright (c) 2014 Chelsio, 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 "iwpm_util.h"

#define IWPM_MAPINFO_HASH_SIZE	512
#define IWPM_MAPINFO_HASH_MASK	(IWPM_MAPINFO_HASH_SIZE - 1)
#define IWPM_REMINFO_HASH_SIZE	64
#define IWPM_REMINFO_HASH_MASK	(IWPM_REMINFO_HASH_SIZE - 1)
#define IWPM_MSG_SIZE		512

static LIST_HEAD(iwpm_nlmsg_req_list);
static DEFINE_SPINLOCK(iwpm_nlmsg_req_lock);

static struct hlist_head *iwpm_hash_bucket;
static DEFINE_SPINLOCK(iwpm_mapinfo_lock);

static struct hlist_head *iwpm_reminfo_bucket;
static DEFINE_SPINLOCK(iwpm_reminfo_lock);

static DEFINE_MUTEX(iwpm_admin_lock);
static struct iwpm_admin_data iwpm_admin;

int iwpm_init(u8 nl_client)
{
	int ret = 0;
	mutex_lock(&iwpm_admin_lock);
	if (atomic_read(&iwpm_admin.refcount) == 0) {
		iwpm_hash_bucket = kcalloc(IWPM_MAPINFO_HASH_SIZE,
					   sizeof(struct hlist_head),
					   GFP_KERNEL);
		if (!iwpm_hash_bucket) {
			ret = -ENOMEM;
			goto init_exit;
		}
		iwpm_reminfo_bucket = kcalloc(IWPM_REMINFO_HASH_SIZE,
					      sizeof(struct hlist_head),
					      GFP_KERNEL);
		if (!iwpm_reminfo_bucket) {
			kfree(iwpm_hash_bucket);
			ret = -ENOMEM;
			goto init_exit;
		}
	}
	atomic_inc(&iwpm_admin.refcount);
init_exit:
	mutex_unlock(&iwpm_admin_lock);
	if (!ret) {
		iwpm_set_valid(nl_client, 1);
		iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
		pr_debug("%s: Mapinfo and reminfo tables are created\n",
				__func__);
	}
	return ret;
}

static void free_hash_bucket(void);
static void free_reminfo_bucket(void);

int iwpm_exit(u8 nl_client)
{

	if (!iwpm_valid_client(nl_client))
		return -EINVAL;
	mutex_lock(&iwpm_admin_lock);
	if (atomic_read(&iwpm_admin.refcount) == 0) {
		mutex_unlock(&iwpm_admin_lock);
		pr_err("%s Incorrect usage - negative refcount\n", __func__);
		return -EINVAL;
	}
	if (atomic_dec_and_test(&iwpm_admin.refcount)) {
		free_hash_bucket();
		free_reminfo_bucket();
		pr_debug("%s: Resources are destroyed\n", __func__);
	}
	mutex_unlock(&iwpm_admin_lock);
	iwpm_set_valid(nl_client, 0);
	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
	return 0;
}

static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage *,
					       struct sockaddr_storage *);

int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
			struct sockaddr_storage *mapped_sockaddr,
			u8 nl_client)
{
	struct hlist_head *hash_bucket_head = NULL;
	struct iwpm_mapping_info *map_info;
	unsigned long flags;
	int ret = -EINVAL;

	if (!iwpm_valid_client(nl_client))
		return ret;
	map_info = kzalloc(sizeof(struct iwpm_mapping_info), GFP_KERNEL);
	if (!map_info)
		return -ENOMEM;

	memcpy(&map_info->local_sockaddr, local_sockaddr,
	       sizeof(struct sockaddr_storage));
	memcpy(&map_info->mapped_sockaddr, mapped_sockaddr,
	       sizeof(struct sockaddr_storage));
	map_info->nl_client = nl_client;

	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
	if (iwpm_hash_bucket) {
		hash_bucket_head = get_mapinfo_hash_bucket(
					&map_info->local_sockaddr,
					&map_info->mapped_sockaddr);
		if (hash_bucket_head) {
			hlist_add_head(&map_info->hlist_node, hash_bucket_head);
			ret = 0;
		}
	}
	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);

	if (!hash_bucket_head)
		kfree(map_info);
	return ret;
}

int iwpm_remove_mapinfo(struct sockaddr_storage *local_sockaddr,
			struct sockaddr_storage *mapped_local_addr)
{
	struct hlist_node *tmp_hlist_node;
	struct hlist_head *hash_bucket_head;
	struct iwpm_mapping_info *map_info = NULL;
	unsigned long flags;
	int ret = -EINVAL;

	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
	if (iwpm_hash_bucket) {
		hash_bucket_head = get_mapinfo_hash_bucket(
					local_sockaddr,
					mapped_local_addr);
		if (!hash_bucket_head)
			goto remove_mapinfo_exit;

		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
					hash_bucket_head, hlist_node) {

			if (!iwpm_compare_sockaddr(&map_info->mapped_sockaddr,
						mapped_local_addr)) {

				hlist_del_init(&map_info->hlist_node);
				kfree(map_info);
				ret = 0;
				break;
			}
		}
	}
remove_mapinfo_exit:
	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
	return ret;
}

static void free_hash_bucket(void)
{
	struct hlist_node *tmp_hlist_node;
	struct iwpm_mapping_info *map_info;
	unsigned long flags;
	int i;

	/* remove all the mapinfo data from the list */
	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
			&iwpm_hash_bucket[i], hlist_node) {

				hlist_del_init(&map_info->hlist_node);
				kfree(map_info);
			}
	}
	/* free the hash list */
	kfree(iwpm_hash_bucket);
	iwpm_hash_bucket = NULL;
	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
}

static void free_reminfo_bucket(void)
{
	struct hlist_node *tmp_hlist_node;
	struct iwpm_remote_info *rem_info;
	unsigned long flags;
	int i;

	/* remove all the remote info from the list */
	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
	for (i = 0; i < IWPM_REMINFO_HASH_SIZE; i++) {
		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
			&iwpm_reminfo_bucket[i], hlist_node) {

				hlist_del_init(&rem_info->hlist_node);
				kfree(rem_info);
			}
	}
	/* free the hash list */
	kfree(iwpm_reminfo_bucket);
	iwpm_reminfo_bucket = NULL;
	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
}

static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage *,
						struct sockaddr_storage *);

void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
{
	struct hlist_head *hash_bucket_head;
	unsigned long flags;

	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
	if (iwpm_reminfo_bucket) {
		hash_bucket_head = get_reminfo_hash_bucket(
					&rem_info->mapped_loc_sockaddr,
					&rem_info->mapped_rem_sockaddr);
		if (hash_bucket_head)
			hlist_add_head(&rem_info->hlist_node, hash_bucket_head);
	}
	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
}

int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
			 struct sockaddr_storage *mapped_rem_addr,
			 struct sockaddr_storage *remote_addr,
			 u8 nl_client)
{
	struct hlist_node *tmp_hlist_node;
	struct hlist_head *hash_bucket_head;
	struct iwpm_remote_info *rem_info = NULL;
	unsigned long flags;
	int ret = -EINVAL;

	if (!iwpm_valid_client(nl_client)) {
		pr_info("%s: Invalid client = %d\n", __func__, nl_client);
		return ret;
	}
	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
	if (iwpm_reminfo_bucket) {
		hash_bucket_head = get_reminfo_hash_bucket(
					mapped_loc_addr,
					mapped_rem_addr);
		if (!hash_bucket_head)
			goto get_remote_info_exit;
		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
					hash_bucket_head, hlist_node) {

			if (!iwpm_compare_sockaddr(&rem_info->mapped_loc_sockaddr,
				mapped_loc_addr) &&
				!iwpm_compare_sockaddr(&rem_info->mapped_rem_sockaddr,
				mapped_rem_addr)) {

				memcpy(remote_addr, &rem_info->remote_sockaddr,
					sizeof(struct sockaddr_storage));
				iwpm_print_sockaddr(remote_addr,
						"get_remote_info: Remote sockaddr:");

				hlist_del_init(&rem_info->hlist_node);
				kfree(rem_info);
				ret = 0;
				break;
			}
		}
	}
get_remote_info_exit:
	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
	return ret;
}

struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
					u8 nl_client, gfp_t gfp)
{
	struct iwpm_nlmsg_request *nlmsg_request = NULL;
	unsigned long flags;

	nlmsg_request = kzalloc(sizeof(struct iwpm_nlmsg_request), gfp);
	if (!nlmsg_request)
		return NULL;

	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
	list_add_tail(&nlmsg_request->inprocess_list, &iwpm_nlmsg_req_list);
	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);

	kref_init(&nlmsg_request->kref);
	kref_get(&nlmsg_request->kref);
	nlmsg_request->nlmsg_seq = nlmsg_seq;
	nlmsg_request->nl_client = nl_client;
	nlmsg_request->request_done = 0;
	nlmsg_request->err_code = 0;
	sema_init(&nlmsg_request->sem, 1);
	down(&nlmsg_request->sem);
	return nlmsg_request;
}

void iwpm_free_nlmsg_request(struct kref *kref)
{
	struct iwpm_nlmsg_request *nlmsg_request;
	unsigned long flags;

	nlmsg_request = container_of(kref, struct iwpm_nlmsg_request, kref);

	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
	list_del_init(&nlmsg_request->inprocess_list);
	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);

	if (!nlmsg_request->request_done)
		pr_debug("%s Freeing incomplete nlmsg request (seq = %u).\n",
			__func__, nlmsg_request->nlmsg_seq);
	kfree(nlmsg_request);
}

struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
{
	struct iwpm_nlmsg_request *nlmsg_request;
	struct iwpm_nlmsg_request *found_request = NULL;
	unsigned long flags;

	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
	list_for_each_entry(nlmsg_request, &iwpm_nlmsg_req_list,
			    inprocess_list) {
		if (nlmsg_request->nlmsg_seq == echo_seq) {
			found_request = nlmsg_request;
			kref_get(&nlmsg_request->kref);
			break;
		}
	}
	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
	return found_request;
}

int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
{
	int ret;

	ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
	if (ret) {
		ret = -EINVAL;
		pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
			__func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
	} else {
		ret = nlmsg_request->err_code;
	}
	kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
	return ret;
}

int iwpm_get_nlmsg_seq(void)
{
	return atomic_inc_return(&iwpm_admin.nlmsg_seq);
}

int iwpm_valid_client(u8 nl_client)
{
	return iwpm_admin.client_list[nl_client];
}

void iwpm_set_valid(u8 nl_client, int valid)
{
	iwpm_admin.client_list[nl_client] = valid;
}

/* valid client */
u32 iwpm_get_registration(u8 nl_client)
{
	return iwpm_admin.reg_list[nl_client];
}

/* valid client */
void iwpm_set_registration(u8 nl_client, u32 reg)
{
	iwpm_admin.reg_list[nl_client] = reg;
}

/* valid client */
u32 iwpm_check_registration(u8 nl_client, u32 reg)
{
	return (iwpm_get_registration(nl_client) & reg);
}

int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
				struct sockaddr_storage *b_sockaddr)
{
	if (a_sockaddr->ss_family != b_sockaddr->ss_family)
		return 1;
	if (a_sockaddr->ss_family == AF_INET) {
		struct sockaddr_in *a4_sockaddr =
			(struct sockaddr_in *)a_sockaddr;
		struct sockaddr_in *b4_sockaddr =
			(struct sockaddr_in *)b_sockaddr;
		if (!memcmp(&a4_sockaddr->sin_addr,
			&b4_sockaddr->sin_addr, sizeof(struct in_addr))
			&& a4_sockaddr->sin_port == b4_sockaddr->sin_port)
				return 0;

	} else if (a_sockaddr->ss_family == AF_INET6) {
		struct sockaddr_in6 *a6_sockaddr =
			(struct sockaddr_in6 *)a_sockaddr;
		struct sockaddr_in6 *b6_sockaddr =
			(struct sockaddr_in6 *)b_sockaddr;
		if (!memcmp(&a6_sockaddr->sin6_addr,
			&b6_sockaddr->sin6_addr, sizeof(struct in6_addr))
			&& a6_sockaddr->sin6_port == b6_sockaddr->sin6_port)
				return 0;

	} else {
		pr_err("%s: Invalid sockaddr family\n", __func__);
	}
	return 1;
}

struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
						int nl_client)
{
	struct sk_buff *skb = NULL;

	skb = dev_alloc_skb(IWPM_MSG_SIZE);
	if (!skb)
		goto create_nlmsg_exit;

	if (!(ibnl_put_msg(skb, nlh, 0, 0, nl_client, nl_op,
			   NLM_F_REQUEST))) {
		pr_warn("%s: Unable to put the nlmsg header\n", __func__);
		dev_kfree_skb(skb);
		skb = NULL;
	}
create_nlmsg_exit:
	return skb;
}

int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
				   const struct nla_policy *nlmsg_policy,
				   struct nlattr *nltb[], const char *msg_type)
{
	int nlh_len = 0;
	int ret;
	const char *err_str = "";

	ret = nlmsg_validate(cb->nlh, nlh_len, policy_max - 1, nlmsg_policy,
			     NULL);
	if (ret) {
		err_str = "Invalid attribute";
		goto parse_nlmsg_error;
	}
	ret = nlmsg_parse(cb->nlh, nlh_len, nltb, policy_max - 1,
			  nlmsg_policy, NULL);
	if (ret) {
		err_str = "Unable to parse the nlmsg";
		goto parse_nlmsg_error;
	}
	ret = iwpm_validate_nlmsg_attr(nltb, policy_max);
	if (ret) {
		err_str = "Invalid NULL attribute";
		goto parse_nlmsg_error;
	}
	return 0;
parse_nlmsg_error:
	pr_warn("%s: %s (msg type %s ret = %d)\n",
			__func__, err_str, msg_type, ret);
	return ret;
}

void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg)
{
	struct sockaddr_in6 *sockaddr_v6;
	struct sockaddr_in *sockaddr_v4;

	switch (sockaddr->ss_family) {
	case AF_INET:
		sockaddr_v4 = (struct sockaddr_in *)sockaddr;
		pr_debug("%s IPV4 %pI4: %u(0x%04X)\n",
			msg, &sockaddr_v4->sin_addr,
			ntohs(sockaddr_v4->sin_port),
			ntohs(sockaddr_v4->sin_port));
		break;
	case AF_INET6:
		sockaddr_v6 = (struct sockaddr_in6 *)sockaddr;
		pr_debug("%s IPV6 %pI6: %u(0x%04X)\n",
			msg, &sockaddr_v6->sin6_addr,
			ntohs(sockaddr_v6->sin6_port),
			ntohs(sockaddr_v6->sin6_port));
		break;
	default:
		break;
	}
}

static u32 iwpm_ipv6_jhash(struct sockaddr_in6 *ipv6_sockaddr)
{
	u32 ipv6_hash = jhash(&ipv6_sockaddr->sin6_addr, sizeof(struct in6_addr), 0);
	u32 hash = jhash_2words(ipv6_hash, (__force u32) ipv6_sockaddr->sin6_port, 0);
	return hash;
}

static u32 iwpm_ipv4_jhash(struct sockaddr_in *ipv4_sockaddr)
{
	u32 ipv4_hash = jhash(&ipv4_sockaddr->sin_addr, sizeof(struct in_addr), 0);
	u32 hash = jhash_2words(ipv4_hash, (__force u32) ipv4_sockaddr->sin_port, 0);
	return hash;
}

static int get_hash_bucket(struct sockaddr_storage *a_sockaddr,
				struct sockaddr_storage *b_sockaddr, u32 *hash)
{
	u32 a_hash, b_hash;

	if (a_sockaddr->ss_family == AF_INET) {
		a_hash = iwpm_ipv4_jhash((struct sockaddr_in *) a_sockaddr);
		b_hash = iwpm_ipv4_jhash((struct sockaddr_in *) b_sockaddr);

	} else if (a_sockaddr->ss_family == AF_INET6) {
		a_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) a_sockaddr);
		b_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) b_sockaddr);
	} else {
		pr_err("%s: Invalid sockaddr family\n", __func__);
		return -EINVAL;
	}

	if (a_hash == b_hash) /* if port mapper isn't available */
		*hash = a_hash;
	else
		*hash = jhash_2words(a_hash, b_hash, 0);
	return 0;
}

static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage
				*local_sockaddr, struct sockaddr_storage
				*mapped_sockaddr)
{
	u32 hash;
	int ret;

	ret = get_hash_bucket(local_sockaddr, mapped_sockaddr, &hash);
	if (ret)
		return NULL;
	return &iwpm_hash_bucket[hash & IWPM_MAPINFO_HASH_MASK];
}

static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage
				*mapped_loc_sockaddr, struct sockaddr_storage
				*mapped_rem_sockaddr)
{
	u32 hash;
	int ret;

	ret = get_hash_bucket(mapped_loc_sockaddr, mapped_rem_sockaddr, &hash);
	if (ret)
		return NULL;
	return &iwpm_reminfo_bucket[hash & IWPM_REMINFO_HASH_MASK];
}

static int send_mapinfo_num(u32 mapping_num, u8 nl_client, int iwpm_pid)
{
	struct sk_buff *skb = NULL;
	struct nlmsghdr *nlh;
	u32 msg_seq;
	const char *err_str = "";
	int ret = -EINVAL;

	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_MAPINFO_NUM, &nlh, nl_client);
	if (!skb) {
		err_str = "Unable to create a nlmsg";
		goto mapinfo_num_error;
	}
	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
	msg_seq = 0;
	err_str = "Unable to put attribute of mapinfo number nlmsg";
	ret = ibnl_put_attr(skb, nlh, sizeof(u32), &msg_seq, IWPM_NLA_MAPINFO_SEQ);
	if (ret)
		goto mapinfo_num_error;
	ret = ibnl_put_attr(skb, nlh, sizeof(u32),
				&mapping_num, IWPM_NLA_MAPINFO_SEND_NUM);
	if (ret)
		goto mapinfo_num_error;

	nlmsg_end(skb, nlh);

	ret = rdma_nl_unicast(skb, iwpm_pid);
	if (ret) {
		skb = NULL;
		err_str = "Unable to send a nlmsg";
		goto mapinfo_num_error;
	}
	pr_debug("%s: Sent mapping number = %d\n", __func__, mapping_num);
	return 0;
mapinfo_num_error:
	pr_info("%s: %s\n", __func__, err_str);
	if (skb)
		dev_kfree_skb(skb);
	return ret;
}

static int send_nlmsg_done(struct sk_buff *skb, u8 nl_client, int iwpm_pid)
{
	struct nlmsghdr *nlh = NULL;
	int ret = 0;

	if (!skb)
		return ret;
	if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
			   RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
		pr_warn("%s Unable to put NLMSG_DONE\n", __func__);
		dev_kfree_skb(skb);
		return -ENOMEM;
	}
	nlh->nlmsg_type = NLMSG_DONE;
	ret = rdma_nl_unicast(skb, iwpm_pid);
	if (ret)
		pr_warn("%s Unable to send a nlmsg\n", __func__);
	return ret;
}

int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid)
{
	struct iwpm_mapping_info *map_info;
	struct sk_buff *skb = NULL;
	struct nlmsghdr *nlh;
	int skb_num = 0, mapping_num = 0;
	int i = 0, nlmsg_bytes = 0;
	unsigned long flags;
	const char *err_str = "";
	int ret;

	skb = dev_alloc_skb(NLMSG_GOODSIZE);
	if (!skb) {
		ret = -ENOMEM;
		err_str = "Unable to allocate skb";
		goto send_mapping_info_exit;
	}
	skb_num++;
	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
	ret = -EINVAL;
	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
		hlist_for_each_entry(map_info, &iwpm_hash_bucket[i],
				     hlist_node) {
			if (map_info->nl_client != nl_client)
				continue;
			nlh = NULL;
			if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
					RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
				ret = -ENOMEM;
				err_str = "Unable to put the nlmsg header";
				goto send_mapping_info_unlock;
			}
			err_str = "Unable to put attribute of the nlmsg";
			ret = ibnl_put_attr(skb, nlh,
					sizeof(struct sockaddr_storage),
					&map_info->local_sockaddr,
					IWPM_NLA_MAPINFO_LOCAL_ADDR);
			if (ret)
				goto send_mapping_info_unlock;

			ret = ibnl_put_attr(skb, nlh,
					sizeof(struct sockaddr_storage),
					&map_info->mapped_sockaddr,
					IWPM_NLA_MAPINFO_MAPPED_ADDR);
			if (ret)
				goto send_mapping_info_unlock;

			nlmsg_end(skb, nlh);

			iwpm_print_sockaddr(&map_info->local_sockaddr,
				"send_mapping_info: Local sockaddr:");
			iwpm_print_sockaddr(&map_info->mapped_sockaddr,
				"send_mapping_info: Mapped local sockaddr:");
			mapping_num++;
			nlmsg_bytes += nlh->nlmsg_len;

			/* check if all mappings can fit in one skb */
			if (NLMSG_GOODSIZE - nlmsg_bytes < nlh->nlmsg_len * 2) {
				/* and leave room for NLMSG_DONE */
				nlmsg_bytes = 0;
				skb_num++;
				spin_unlock_irqrestore(&iwpm_mapinfo_lock,
						       flags);
				/* send the skb */
				ret = send_nlmsg_done(skb, nl_client, iwpm_pid);
				skb = NULL;
				if (ret) {
					err_str = "Unable to send map info";
					goto send_mapping_info_exit;
				}
				if (skb_num == IWPM_MAPINFO_SKB_COUNT) {
					ret = -ENOMEM;
					err_str = "Insufficient skbs for map info";
					goto send_mapping_info_exit;
				}
				skb = dev_alloc_skb(NLMSG_GOODSIZE);
				if (!skb) {
					ret = -ENOMEM;
					err_str = "Unable to allocate skb";
					goto send_mapping_info_exit;
				}
				spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
			}
		}
	}
send_mapping_info_unlock:
	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
send_mapping_info_exit:
	if (ret) {
		pr_warn("%s: %s (ret = %d)\n", __func__, err_str, ret);
		if (skb)
			dev_kfree_skb(skb);
		return ret;
	}
	send_nlmsg_done(skb, nl_client, iwpm_pid);
	return send_mapinfo_num(mapping_num, nl_client, iwpm_pid);
}

int iwpm_mapinfo_available(void)
{
	unsigned long flags;
	int full_bucket = 0, i = 0;

	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
	if (iwpm_hash_bucket) {
		for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
			if (!hlist_empty(&iwpm_hash_bucket[i])) {
				full_bucket = 1;
				break;
			}
		}
	}
	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
	return full_bucket;
}