1 /*
2  * Copyright (c) 2014 Chelsio, Inc. All rights reserved.
3  * Copyright (c) 2014 Intel Corporation. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *	  copyright notice, this list of conditions and the following
17  *	  disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *	  copyright notice, this list of conditions and the following
21  *	  disclaimer in the documentation and/or other materials
22  *	  provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include "iwpm_util.h"
35 
36 #define IWPM_MAPINFO_HASH_SIZE	512
37 #define IWPM_MAPINFO_HASH_MASK	(IWPM_MAPINFO_HASH_SIZE - 1)
38 #define IWPM_REMINFO_HASH_SIZE	64
39 #define IWPM_REMINFO_HASH_MASK	(IWPM_REMINFO_HASH_SIZE - 1)
40 #define IWPM_MSG_SIZE		512
41 
42 static LIST_HEAD(iwpm_nlmsg_req_list);
43 static DEFINE_SPINLOCK(iwpm_nlmsg_req_lock);
44 
45 static struct hlist_head *iwpm_hash_bucket;
46 static DEFINE_SPINLOCK(iwpm_mapinfo_lock);
47 
48 static struct hlist_head *iwpm_reminfo_bucket;
49 static DEFINE_SPINLOCK(iwpm_reminfo_lock);
50 
51 static DEFINE_MUTEX(iwpm_admin_lock);
52 static struct iwpm_admin_data iwpm_admin;
53 
54 int iwpm_init(u8 nl_client)
55 {
56 	int ret = 0;
57 	if (iwpm_valid_client(nl_client))
58 		return -EINVAL;
59 	mutex_lock(&iwpm_admin_lock);
60 	if (atomic_read(&iwpm_admin.refcount) == 0) {
61 		iwpm_hash_bucket = kzalloc(IWPM_MAPINFO_HASH_SIZE *
62 					sizeof(struct hlist_head), GFP_KERNEL);
63 		if (!iwpm_hash_bucket) {
64 			ret = -ENOMEM;
65 			pr_err("%s Unable to create mapinfo hash table\n", __func__);
66 			goto init_exit;
67 		}
68 		iwpm_reminfo_bucket = kzalloc(IWPM_REMINFO_HASH_SIZE *
69 					sizeof(struct hlist_head), GFP_KERNEL);
70 		if (!iwpm_reminfo_bucket) {
71 			kfree(iwpm_hash_bucket);
72 			ret = -ENOMEM;
73 			pr_err("%s Unable to create reminfo hash table\n", __func__);
74 			goto init_exit;
75 		}
76 	}
77 	atomic_inc(&iwpm_admin.refcount);
78 init_exit:
79 	mutex_unlock(&iwpm_admin_lock);
80 	if (!ret) {
81 		iwpm_set_valid(nl_client, 1);
82 		iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
83 		pr_debug("%s: Mapinfo and reminfo tables are created\n",
84 				__func__);
85 	}
86 	return ret;
87 }
88 EXPORT_SYMBOL(iwpm_init);
89 
90 static void free_hash_bucket(void);
91 static void free_reminfo_bucket(void);
92 
93 int iwpm_exit(u8 nl_client)
94 {
95 
96 	if (!iwpm_valid_client(nl_client))
97 		return -EINVAL;
98 	mutex_lock(&iwpm_admin_lock);
99 	if (atomic_read(&iwpm_admin.refcount) == 0) {
100 		mutex_unlock(&iwpm_admin_lock);
101 		pr_err("%s Incorrect usage - negative refcount\n", __func__);
102 		return -EINVAL;
103 	}
104 	if (atomic_dec_and_test(&iwpm_admin.refcount)) {
105 		free_hash_bucket();
106 		free_reminfo_bucket();
107 		pr_debug("%s: Resources are destroyed\n", __func__);
108 	}
109 	mutex_unlock(&iwpm_admin_lock);
110 	iwpm_set_valid(nl_client, 0);
111 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
112 	return 0;
113 }
114 EXPORT_SYMBOL(iwpm_exit);
115 
116 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage *,
117 					       struct sockaddr_storage *);
118 
119 int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
120 			struct sockaddr_storage *mapped_sockaddr,
121 			u8 nl_client)
122 {
123 	struct hlist_head *hash_bucket_head;
124 	struct iwpm_mapping_info *map_info;
125 	unsigned long flags;
126 	int ret = -EINVAL;
127 
128 	if (!iwpm_valid_client(nl_client))
129 		return ret;
130 	map_info = kzalloc(sizeof(struct iwpm_mapping_info), GFP_KERNEL);
131 	if (!map_info) {
132 		pr_err("%s: Unable to allocate a mapping info\n", __func__);
133 		return -ENOMEM;
134 	}
135 	memcpy(&map_info->local_sockaddr, local_sockaddr,
136 	       sizeof(struct sockaddr_storage));
137 	memcpy(&map_info->mapped_sockaddr, mapped_sockaddr,
138 	       sizeof(struct sockaddr_storage));
139 	map_info->nl_client = nl_client;
140 
141 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
142 	if (iwpm_hash_bucket) {
143 		hash_bucket_head = get_mapinfo_hash_bucket(
144 					&map_info->local_sockaddr,
145 					&map_info->mapped_sockaddr);
146 		if (hash_bucket_head) {
147 			hlist_add_head(&map_info->hlist_node, hash_bucket_head);
148 			ret = 0;
149 		}
150 	}
151 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
152 	return ret;
153 }
154 EXPORT_SYMBOL(iwpm_create_mapinfo);
155 
156 int iwpm_remove_mapinfo(struct sockaddr_storage *local_sockaddr,
157 			struct sockaddr_storage *mapped_local_addr)
158 {
159 	struct hlist_node *tmp_hlist_node;
160 	struct hlist_head *hash_bucket_head;
161 	struct iwpm_mapping_info *map_info = NULL;
162 	unsigned long flags;
163 	int ret = -EINVAL;
164 
165 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
166 	if (iwpm_hash_bucket) {
167 		hash_bucket_head = get_mapinfo_hash_bucket(
168 					local_sockaddr,
169 					mapped_local_addr);
170 		if (!hash_bucket_head)
171 			goto remove_mapinfo_exit;
172 
173 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
174 					hash_bucket_head, hlist_node) {
175 
176 			if (!iwpm_compare_sockaddr(&map_info->mapped_sockaddr,
177 						mapped_local_addr)) {
178 
179 				hlist_del_init(&map_info->hlist_node);
180 				kfree(map_info);
181 				ret = 0;
182 				break;
183 			}
184 		}
185 	}
186 remove_mapinfo_exit:
187 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
188 	return ret;
189 }
190 EXPORT_SYMBOL(iwpm_remove_mapinfo);
191 
192 static void free_hash_bucket(void)
193 {
194 	struct hlist_node *tmp_hlist_node;
195 	struct iwpm_mapping_info *map_info;
196 	unsigned long flags;
197 	int i;
198 
199 	/* remove all the mapinfo data from the list */
200 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
201 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
202 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
203 			&iwpm_hash_bucket[i], hlist_node) {
204 
205 				hlist_del_init(&map_info->hlist_node);
206 				kfree(map_info);
207 			}
208 	}
209 	/* free the hash list */
210 	kfree(iwpm_hash_bucket);
211 	iwpm_hash_bucket = NULL;
212 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
213 }
214 
215 static void free_reminfo_bucket(void)
216 {
217 	struct hlist_node *tmp_hlist_node;
218 	struct iwpm_remote_info *rem_info;
219 	unsigned long flags;
220 	int i;
221 
222 	/* remove all the remote info from the list */
223 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
224 	for (i = 0; i < IWPM_REMINFO_HASH_SIZE; i++) {
225 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
226 			&iwpm_reminfo_bucket[i], hlist_node) {
227 
228 				hlist_del_init(&rem_info->hlist_node);
229 				kfree(rem_info);
230 			}
231 	}
232 	/* free the hash list */
233 	kfree(iwpm_reminfo_bucket);
234 	iwpm_reminfo_bucket = NULL;
235 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
236 }
237 
238 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage *,
239 						struct sockaddr_storage *);
240 
241 void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
242 {
243 	struct hlist_head *hash_bucket_head;
244 	unsigned long flags;
245 
246 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
247 	if (iwpm_reminfo_bucket) {
248 		hash_bucket_head = get_reminfo_hash_bucket(
249 					&rem_info->mapped_loc_sockaddr,
250 					&rem_info->mapped_rem_sockaddr);
251 		if (hash_bucket_head)
252 			hlist_add_head(&rem_info->hlist_node, hash_bucket_head);
253 	}
254 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
255 }
256 
257 int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
258 			 struct sockaddr_storage *mapped_rem_addr,
259 			 struct sockaddr_storage *remote_addr,
260 			 u8 nl_client)
261 {
262 	struct hlist_node *tmp_hlist_node;
263 	struct hlist_head *hash_bucket_head;
264 	struct iwpm_remote_info *rem_info = NULL;
265 	unsigned long flags;
266 	int ret = -EINVAL;
267 
268 	if (!iwpm_valid_client(nl_client)) {
269 		pr_info("%s: Invalid client = %d\n", __func__, nl_client);
270 		return ret;
271 	}
272 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
273 	if (iwpm_reminfo_bucket) {
274 		hash_bucket_head = get_reminfo_hash_bucket(
275 					mapped_loc_addr,
276 					mapped_rem_addr);
277 		if (!hash_bucket_head)
278 			goto get_remote_info_exit;
279 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
280 					hash_bucket_head, hlist_node) {
281 
282 			if (!iwpm_compare_sockaddr(&rem_info->mapped_loc_sockaddr,
283 				mapped_loc_addr) &&
284 				!iwpm_compare_sockaddr(&rem_info->mapped_rem_sockaddr,
285 				mapped_rem_addr)) {
286 
287 				memcpy(remote_addr, &rem_info->remote_sockaddr,
288 					sizeof(struct sockaddr_storage));
289 				iwpm_print_sockaddr(remote_addr,
290 						"get_remote_info: Remote sockaddr:");
291 
292 				hlist_del_init(&rem_info->hlist_node);
293 				kfree(rem_info);
294 				ret = 0;
295 				break;
296 			}
297 		}
298 	}
299 get_remote_info_exit:
300 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
301 	return ret;
302 }
303 EXPORT_SYMBOL(iwpm_get_remote_info);
304 
305 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
306 					u8 nl_client, gfp_t gfp)
307 {
308 	struct iwpm_nlmsg_request *nlmsg_request = NULL;
309 	unsigned long flags;
310 
311 	nlmsg_request = kzalloc(sizeof(struct iwpm_nlmsg_request), gfp);
312 	if (!nlmsg_request) {
313 		pr_err("%s Unable to allocate a nlmsg_request\n", __func__);
314 		return NULL;
315 	}
316 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
317 	list_add_tail(&nlmsg_request->inprocess_list, &iwpm_nlmsg_req_list);
318 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
319 
320 	kref_init(&nlmsg_request->kref);
321 	kref_get(&nlmsg_request->kref);
322 	nlmsg_request->nlmsg_seq = nlmsg_seq;
323 	nlmsg_request->nl_client = nl_client;
324 	nlmsg_request->request_done = 0;
325 	nlmsg_request->err_code = 0;
326 	sema_init(&nlmsg_request->sem, 1);
327 	down(&nlmsg_request->sem);
328 	return nlmsg_request;
329 }
330 
331 void iwpm_free_nlmsg_request(struct kref *kref)
332 {
333 	struct iwpm_nlmsg_request *nlmsg_request;
334 	unsigned long flags;
335 
336 	nlmsg_request = container_of(kref, struct iwpm_nlmsg_request, kref);
337 
338 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
339 	list_del_init(&nlmsg_request->inprocess_list);
340 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
341 
342 	if (!nlmsg_request->request_done)
343 		pr_debug("%s Freeing incomplete nlmsg request (seq = %u).\n",
344 			__func__, nlmsg_request->nlmsg_seq);
345 	kfree(nlmsg_request);
346 }
347 
348 struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
349 {
350 	struct iwpm_nlmsg_request *nlmsg_request;
351 	struct iwpm_nlmsg_request *found_request = NULL;
352 	unsigned long flags;
353 
354 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
355 	list_for_each_entry(nlmsg_request, &iwpm_nlmsg_req_list,
356 			    inprocess_list) {
357 		if (nlmsg_request->nlmsg_seq == echo_seq) {
358 			found_request = nlmsg_request;
359 			kref_get(&nlmsg_request->kref);
360 			break;
361 		}
362 	}
363 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
364 	return found_request;
365 }
366 
367 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
368 {
369 	int ret;
370 
371 	ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
372 	if (ret) {
373 		ret = -EINVAL;
374 		pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
375 			__func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
376 	} else {
377 		ret = nlmsg_request->err_code;
378 	}
379 	kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
380 	return ret;
381 }
382 
383 int iwpm_get_nlmsg_seq(void)
384 {
385 	return atomic_inc_return(&iwpm_admin.nlmsg_seq);
386 }
387 
388 int iwpm_valid_client(u8 nl_client)
389 {
390 	if (nl_client >= RDMA_NL_NUM_CLIENTS)
391 		return 0;
392 	return iwpm_admin.client_list[nl_client];
393 }
394 
395 void iwpm_set_valid(u8 nl_client, int valid)
396 {
397 	if (nl_client >= RDMA_NL_NUM_CLIENTS)
398 		return;
399 	iwpm_admin.client_list[nl_client] = valid;
400 }
401 
402 /* valid client */
403 u32 iwpm_get_registration(u8 nl_client)
404 {
405 	return iwpm_admin.reg_list[nl_client];
406 }
407 
408 /* valid client */
409 void iwpm_set_registration(u8 nl_client, u32 reg)
410 {
411 	iwpm_admin.reg_list[nl_client] = reg;
412 }
413 
414 /* valid client */
415 u32 iwpm_check_registration(u8 nl_client, u32 reg)
416 {
417 	return (iwpm_get_registration(nl_client) & reg);
418 }
419 
420 int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
421 				struct sockaddr_storage *b_sockaddr)
422 {
423 	if (a_sockaddr->ss_family != b_sockaddr->ss_family)
424 		return 1;
425 	if (a_sockaddr->ss_family == AF_INET) {
426 		struct sockaddr_in *a4_sockaddr =
427 			(struct sockaddr_in *)a_sockaddr;
428 		struct sockaddr_in *b4_sockaddr =
429 			(struct sockaddr_in *)b_sockaddr;
430 		if (!memcmp(&a4_sockaddr->sin_addr,
431 			&b4_sockaddr->sin_addr, sizeof(struct in_addr))
432 			&& a4_sockaddr->sin_port == b4_sockaddr->sin_port)
433 				return 0;
434 
435 	} else if (a_sockaddr->ss_family == AF_INET6) {
436 		struct sockaddr_in6 *a6_sockaddr =
437 			(struct sockaddr_in6 *)a_sockaddr;
438 		struct sockaddr_in6 *b6_sockaddr =
439 			(struct sockaddr_in6 *)b_sockaddr;
440 		if (!memcmp(&a6_sockaddr->sin6_addr,
441 			&b6_sockaddr->sin6_addr, sizeof(struct in6_addr))
442 			&& a6_sockaddr->sin6_port == b6_sockaddr->sin6_port)
443 				return 0;
444 
445 	} else {
446 		pr_err("%s: Invalid sockaddr family\n", __func__);
447 	}
448 	return 1;
449 }
450 
451 struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
452 						int nl_client)
453 {
454 	struct sk_buff *skb = NULL;
455 
456 	skb = dev_alloc_skb(IWPM_MSG_SIZE);
457 	if (!skb) {
458 		pr_err("%s Unable to allocate skb\n", __func__);
459 		goto create_nlmsg_exit;
460 	}
461 	if (!(ibnl_put_msg(skb, nlh, 0, 0, nl_client, nl_op,
462 			   NLM_F_REQUEST))) {
463 		pr_warn("%s: Unable to put the nlmsg header\n", __func__);
464 		dev_kfree_skb(skb);
465 		skb = NULL;
466 	}
467 create_nlmsg_exit:
468 	return skb;
469 }
470 
471 int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
472 				   const struct nla_policy *nlmsg_policy,
473 				   struct nlattr *nltb[], const char *msg_type)
474 {
475 	int nlh_len = 0;
476 	int ret;
477 	const char *err_str = "";
478 
479 	ret = nlmsg_validate(cb->nlh, nlh_len, policy_max-1, nlmsg_policy);
480 	if (ret) {
481 		err_str = "Invalid attribute";
482 		goto parse_nlmsg_error;
483 	}
484 	ret = nlmsg_parse(cb->nlh, nlh_len, nltb, policy_max-1, nlmsg_policy);
485 	if (ret) {
486 		err_str = "Unable to parse the nlmsg";
487 		goto parse_nlmsg_error;
488 	}
489 	ret = iwpm_validate_nlmsg_attr(nltb, policy_max);
490 	if (ret) {
491 		err_str = "Invalid NULL attribute";
492 		goto parse_nlmsg_error;
493 	}
494 	return 0;
495 parse_nlmsg_error:
496 	pr_warn("%s: %s (msg type %s ret = %d)\n",
497 			__func__, err_str, msg_type, ret);
498 	return ret;
499 }
500 
501 void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg)
502 {
503 	struct sockaddr_in6 *sockaddr_v6;
504 	struct sockaddr_in *sockaddr_v4;
505 
506 	switch (sockaddr->ss_family) {
507 	case AF_INET:
508 		sockaddr_v4 = (struct sockaddr_in *)sockaddr;
509 		pr_debug("%s IPV4 %pI4: %u(0x%04X)\n",
510 			msg, &sockaddr_v4->sin_addr,
511 			ntohs(sockaddr_v4->sin_port),
512 			ntohs(sockaddr_v4->sin_port));
513 		break;
514 	case AF_INET6:
515 		sockaddr_v6 = (struct sockaddr_in6 *)sockaddr;
516 		pr_debug("%s IPV6 %pI6: %u(0x%04X)\n",
517 			msg, &sockaddr_v6->sin6_addr,
518 			ntohs(sockaddr_v6->sin6_port),
519 			ntohs(sockaddr_v6->sin6_port));
520 		break;
521 	default:
522 		break;
523 	}
524 }
525 
526 static u32 iwpm_ipv6_jhash(struct sockaddr_in6 *ipv6_sockaddr)
527 {
528 	u32 ipv6_hash = jhash(&ipv6_sockaddr->sin6_addr, sizeof(struct in6_addr), 0);
529 	u32 hash = jhash_2words(ipv6_hash, (__force u32) ipv6_sockaddr->sin6_port, 0);
530 	return hash;
531 }
532 
533 static u32 iwpm_ipv4_jhash(struct sockaddr_in *ipv4_sockaddr)
534 {
535 	u32 ipv4_hash = jhash(&ipv4_sockaddr->sin_addr, sizeof(struct in_addr), 0);
536 	u32 hash = jhash_2words(ipv4_hash, (__force u32) ipv4_sockaddr->sin_port, 0);
537 	return hash;
538 }
539 
540 static int get_hash_bucket(struct sockaddr_storage *a_sockaddr,
541 				struct sockaddr_storage *b_sockaddr, u32 *hash)
542 {
543 	u32 a_hash, b_hash;
544 
545 	if (a_sockaddr->ss_family == AF_INET) {
546 		a_hash = iwpm_ipv4_jhash((struct sockaddr_in *) a_sockaddr);
547 		b_hash = iwpm_ipv4_jhash((struct sockaddr_in *) b_sockaddr);
548 
549 	} else if (a_sockaddr->ss_family == AF_INET6) {
550 		a_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) a_sockaddr);
551 		b_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) b_sockaddr);
552 	} else {
553 		pr_err("%s: Invalid sockaddr family\n", __func__);
554 		return -EINVAL;
555 	}
556 
557 	if (a_hash == b_hash) /* if port mapper isn't available */
558 		*hash = a_hash;
559 	else
560 		*hash = jhash_2words(a_hash, b_hash, 0);
561 	return 0;
562 }
563 
564 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage
565 				*local_sockaddr, struct sockaddr_storage
566 				*mapped_sockaddr)
567 {
568 	u32 hash;
569 	int ret;
570 
571 	ret = get_hash_bucket(local_sockaddr, mapped_sockaddr, &hash);
572 	if (ret)
573 		return NULL;
574 	return &iwpm_hash_bucket[hash & IWPM_MAPINFO_HASH_MASK];
575 }
576 
577 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage
578 				*mapped_loc_sockaddr, struct sockaddr_storage
579 				*mapped_rem_sockaddr)
580 {
581 	u32 hash;
582 	int ret;
583 
584 	ret = get_hash_bucket(mapped_loc_sockaddr, mapped_rem_sockaddr, &hash);
585 	if (ret)
586 		return NULL;
587 	return &iwpm_reminfo_bucket[hash & IWPM_REMINFO_HASH_MASK];
588 }
589 
590 static int send_mapinfo_num(u32 mapping_num, u8 nl_client, int iwpm_pid)
591 {
592 	struct sk_buff *skb = NULL;
593 	struct nlmsghdr *nlh;
594 	u32 msg_seq;
595 	const char *err_str = "";
596 	int ret = -EINVAL;
597 
598 	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_MAPINFO_NUM, &nlh, nl_client);
599 	if (!skb) {
600 		err_str = "Unable to create a nlmsg";
601 		goto mapinfo_num_error;
602 	}
603 	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
604 	msg_seq = 0;
605 	err_str = "Unable to put attribute of mapinfo number nlmsg";
606 	ret = ibnl_put_attr(skb, nlh, sizeof(u32), &msg_seq, IWPM_NLA_MAPINFO_SEQ);
607 	if (ret)
608 		goto mapinfo_num_error;
609 	ret = ibnl_put_attr(skb, nlh, sizeof(u32),
610 				&mapping_num, IWPM_NLA_MAPINFO_SEND_NUM);
611 	if (ret)
612 		goto mapinfo_num_error;
613 	ret = ibnl_unicast(skb, nlh, iwpm_pid);
614 	if (ret) {
615 		skb = NULL;
616 		err_str = "Unable to send a nlmsg";
617 		goto mapinfo_num_error;
618 	}
619 	pr_debug("%s: Sent mapping number = %d\n", __func__, mapping_num);
620 	return 0;
621 mapinfo_num_error:
622 	pr_info("%s: %s\n", __func__, err_str);
623 	if (skb)
624 		dev_kfree_skb(skb);
625 	return ret;
626 }
627 
628 static int send_nlmsg_done(struct sk_buff *skb, u8 nl_client, int iwpm_pid)
629 {
630 	struct nlmsghdr *nlh = NULL;
631 	int ret = 0;
632 
633 	if (!skb)
634 		return ret;
635 	if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
636 			   RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
637 		pr_warn("%s Unable to put NLMSG_DONE\n", __func__);
638 		dev_kfree_skb(skb);
639 		return -ENOMEM;
640 	}
641 	nlh->nlmsg_type = NLMSG_DONE;
642 	ret = ibnl_unicast(skb, (struct nlmsghdr *)skb->data, iwpm_pid);
643 	if (ret)
644 		pr_warn("%s Unable to send a nlmsg\n", __func__);
645 	return ret;
646 }
647 
648 int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid)
649 {
650 	struct iwpm_mapping_info *map_info;
651 	struct sk_buff *skb = NULL;
652 	struct nlmsghdr *nlh;
653 	int skb_num = 0, mapping_num = 0;
654 	int i = 0, nlmsg_bytes = 0;
655 	unsigned long flags;
656 	const char *err_str = "";
657 	int ret;
658 
659 	skb = dev_alloc_skb(NLMSG_GOODSIZE);
660 	if (!skb) {
661 		ret = -ENOMEM;
662 		err_str = "Unable to allocate skb";
663 		goto send_mapping_info_exit;
664 	}
665 	skb_num++;
666 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
667 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
668 		hlist_for_each_entry(map_info, &iwpm_hash_bucket[i],
669 				     hlist_node) {
670 			if (map_info->nl_client != nl_client)
671 				continue;
672 			nlh = NULL;
673 			if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
674 					RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
675 				ret = -ENOMEM;
676 				err_str = "Unable to put the nlmsg header";
677 				goto send_mapping_info_unlock;
678 			}
679 			err_str = "Unable to put attribute of the nlmsg";
680 			ret = ibnl_put_attr(skb, nlh,
681 					sizeof(struct sockaddr_storage),
682 					&map_info->local_sockaddr,
683 					IWPM_NLA_MAPINFO_LOCAL_ADDR);
684 			if (ret)
685 				goto send_mapping_info_unlock;
686 
687 			ret = ibnl_put_attr(skb, nlh,
688 					sizeof(struct sockaddr_storage),
689 					&map_info->mapped_sockaddr,
690 					IWPM_NLA_MAPINFO_MAPPED_ADDR);
691 			if (ret)
692 				goto send_mapping_info_unlock;
693 
694 			iwpm_print_sockaddr(&map_info->local_sockaddr,
695 				"send_mapping_info: Local sockaddr:");
696 			iwpm_print_sockaddr(&map_info->mapped_sockaddr,
697 				"send_mapping_info: Mapped local sockaddr:");
698 			mapping_num++;
699 			nlmsg_bytes += nlh->nlmsg_len;
700 
701 			/* check if all mappings can fit in one skb */
702 			if (NLMSG_GOODSIZE - nlmsg_bytes < nlh->nlmsg_len * 2) {
703 				/* and leave room for NLMSG_DONE */
704 				nlmsg_bytes = 0;
705 				skb_num++;
706 				spin_unlock_irqrestore(&iwpm_mapinfo_lock,
707 						       flags);
708 				/* send the skb */
709 				ret = send_nlmsg_done(skb, nl_client, iwpm_pid);
710 				skb = NULL;
711 				if (ret) {
712 					err_str = "Unable to send map info";
713 					goto send_mapping_info_exit;
714 				}
715 				if (skb_num == IWPM_MAPINFO_SKB_COUNT) {
716 					ret = -ENOMEM;
717 					err_str = "Insufficient skbs for map info";
718 					goto send_mapping_info_exit;
719 				}
720 				skb = dev_alloc_skb(NLMSG_GOODSIZE);
721 				if (!skb) {
722 					ret = -ENOMEM;
723 					err_str = "Unable to allocate skb";
724 					goto send_mapping_info_exit;
725 				}
726 				spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
727 			}
728 		}
729 	}
730 send_mapping_info_unlock:
731 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
732 send_mapping_info_exit:
733 	if (ret) {
734 		pr_warn("%s: %s (ret = %d)\n", __func__, err_str, ret);
735 		if (skb)
736 			dev_kfree_skb(skb);
737 		return ret;
738 	}
739 	send_nlmsg_done(skb, nl_client, iwpm_pid);
740 	return send_mapinfo_num(mapping_num, nl_client, iwpm_pid);
741 }
742 
743 int iwpm_mapinfo_available(void)
744 {
745 	unsigned long flags;
746 	int full_bucket = 0, i = 0;
747 
748 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
749 	if (iwpm_hash_bucket) {
750 		for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
751 			if (!hlist_empty(&iwpm_hash_bucket[i])) {
752 				full_bucket = 1;
753 				break;
754 			}
755 		}
756 	}
757 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
758 	return full_bucket;
759 }
760