xref: /openbmc/linux/drivers/infiniband/core/iwpm_util.c (revision 9c6d26df1fae6ad4718d51c48e6517913304ed27)
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 	mutex_lock(&iwpm_admin_lock);
58 	if (atomic_read(&iwpm_admin.refcount) == 0) {
59 		iwpm_hash_bucket = kzalloc(IWPM_MAPINFO_HASH_SIZE *
60 					sizeof(struct hlist_head), GFP_KERNEL);
61 		if (!iwpm_hash_bucket) {
62 			ret = -ENOMEM;
63 			goto init_exit;
64 		}
65 		iwpm_reminfo_bucket = kzalloc(IWPM_REMINFO_HASH_SIZE *
66 					sizeof(struct hlist_head), GFP_KERNEL);
67 		if (!iwpm_reminfo_bucket) {
68 			kfree(iwpm_hash_bucket);
69 			ret = -ENOMEM;
70 			goto init_exit;
71 		}
72 	}
73 	atomic_inc(&iwpm_admin.refcount);
74 init_exit:
75 	mutex_unlock(&iwpm_admin_lock);
76 	if (!ret) {
77 		iwpm_set_valid(nl_client, 1);
78 		iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
79 		pr_debug("%s: Mapinfo and reminfo tables are created\n",
80 				__func__);
81 	}
82 	return ret;
83 }
84 
85 static void free_hash_bucket(void);
86 static void free_reminfo_bucket(void);
87 
88 int iwpm_exit(u8 nl_client)
89 {
90 
91 	if (!iwpm_valid_client(nl_client))
92 		return -EINVAL;
93 	mutex_lock(&iwpm_admin_lock);
94 	if (atomic_read(&iwpm_admin.refcount) == 0) {
95 		mutex_unlock(&iwpm_admin_lock);
96 		pr_err("%s Incorrect usage - negative refcount\n", __func__);
97 		return -EINVAL;
98 	}
99 	if (atomic_dec_and_test(&iwpm_admin.refcount)) {
100 		free_hash_bucket();
101 		free_reminfo_bucket();
102 		pr_debug("%s: Resources are destroyed\n", __func__);
103 	}
104 	mutex_unlock(&iwpm_admin_lock);
105 	iwpm_set_valid(nl_client, 0);
106 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
107 	return 0;
108 }
109 
110 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage *,
111 					       struct sockaddr_storage *);
112 
113 int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
114 			struct sockaddr_storage *mapped_sockaddr,
115 			u8 nl_client)
116 {
117 	struct hlist_head *hash_bucket_head;
118 	struct iwpm_mapping_info *map_info;
119 	unsigned long flags;
120 	int ret = -EINVAL;
121 
122 	if (!iwpm_valid_client(nl_client))
123 		return ret;
124 	map_info = kzalloc(sizeof(struct iwpm_mapping_info), GFP_KERNEL);
125 	if (!map_info)
126 		return -ENOMEM;
127 
128 	memcpy(&map_info->local_sockaddr, local_sockaddr,
129 	       sizeof(struct sockaddr_storage));
130 	memcpy(&map_info->mapped_sockaddr, mapped_sockaddr,
131 	       sizeof(struct sockaddr_storage));
132 	map_info->nl_client = nl_client;
133 
134 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
135 	if (iwpm_hash_bucket) {
136 		hash_bucket_head = get_mapinfo_hash_bucket(
137 					&map_info->local_sockaddr,
138 					&map_info->mapped_sockaddr);
139 		if (hash_bucket_head) {
140 			hlist_add_head(&map_info->hlist_node, hash_bucket_head);
141 			ret = 0;
142 		}
143 	}
144 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
145 	return ret;
146 }
147 
148 int iwpm_remove_mapinfo(struct sockaddr_storage *local_sockaddr,
149 			struct sockaddr_storage *mapped_local_addr)
150 {
151 	struct hlist_node *tmp_hlist_node;
152 	struct hlist_head *hash_bucket_head;
153 	struct iwpm_mapping_info *map_info = NULL;
154 	unsigned long flags;
155 	int ret = -EINVAL;
156 
157 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
158 	if (iwpm_hash_bucket) {
159 		hash_bucket_head = get_mapinfo_hash_bucket(
160 					local_sockaddr,
161 					mapped_local_addr);
162 		if (!hash_bucket_head)
163 			goto remove_mapinfo_exit;
164 
165 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
166 					hash_bucket_head, hlist_node) {
167 
168 			if (!iwpm_compare_sockaddr(&map_info->mapped_sockaddr,
169 						mapped_local_addr)) {
170 
171 				hlist_del_init(&map_info->hlist_node);
172 				kfree(map_info);
173 				ret = 0;
174 				break;
175 			}
176 		}
177 	}
178 remove_mapinfo_exit:
179 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
180 	return ret;
181 }
182 
183 static void free_hash_bucket(void)
184 {
185 	struct hlist_node *tmp_hlist_node;
186 	struct iwpm_mapping_info *map_info;
187 	unsigned long flags;
188 	int i;
189 
190 	/* remove all the mapinfo data from the list */
191 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
192 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
193 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
194 			&iwpm_hash_bucket[i], hlist_node) {
195 
196 				hlist_del_init(&map_info->hlist_node);
197 				kfree(map_info);
198 			}
199 	}
200 	/* free the hash list */
201 	kfree(iwpm_hash_bucket);
202 	iwpm_hash_bucket = NULL;
203 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
204 }
205 
206 static void free_reminfo_bucket(void)
207 {
208 	struct hlist_node *tmp_hlist_node;
209 	struct iwpm_remote_info *rem_info;
210 	unsigned long flags;
211 	int i;
212 
213 	/* remove all the remote info from the list */
214 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
215 	for (i = 0; i < IWPM_REMINFO_HASH_SIZE; i++) {
216 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
217 			&iwpm_reminfo_bucket[i], hlist_node) {
218 
219 				hlist_del_init(&rem_info->hlist_node);
220 				kfree(rem_info);
221 			}
222 	}
223 	/* free the hash list */
224 	kfree(iwpm_reminfo_bucket);
225 	iwpm_reminfo_bucket = NULL;
226 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
227 }
228 
229 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage *,
230 						struct sockaddr_storage *);
231 
232 void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
233 {
234 	struct hlist_head *hash_bucket_head;
235 	unsigned long flags;
236 
237 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
238 	if (iwpm_reminfo_bucket) {
239 		hash_bucket_head = get_reminfo_hash_bucket(
240 					&rem_info->mapped_loc_sockaddr,
241 					&rem_info->mapped_rem_sockaddr);
242 		if (hash_bucket_head)
243 			hlist_add_head(&rem_info->hlist_node, hash_bucket_head);
244 	}
245 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
246 }
247 
248 int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
249 			 struct sockaddr_storage *mapped_rem_addr,
250 			 struct sockaddr_storage *remote_addr,
251 			 u8 nl_client)
252 {
253 	struct hlist_node *tmp_hlist_node;
254 	struct hlist_head *hash_bucket_head;
255 	struct iwpm_remote_info *rem_info = NULL;
256 	unsigned long flags;
257 	int ret = -EINVAL;
258 
259 	if (!iwpm_valid_client(nl_client)) {
260 		pr_info("%s: Invalid client = %d\n", __func__, nl_client);
261 		return ret;
262 	}
263 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
264 	if (iwpm_reminfo_bucket) {
265 		hash_bucket_head = get_reminfo_hash_bucket(
266 					mapped_loc_addr,
267 					mapped_rem_addr);
268 		if (!hash_bucket_head)
269 			goto get_remote_info_exit;
270 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
271 					hash_bucket_head, hlist_node) {
272 
273 			if (!iwpm_compare_sockaddr(&rem_info->mapped_loc_sockaddr,
274 				mapped_loc_addr) &&
275 				!iwpm_compare_sockaddr(&rem_info->mapped_rem_sockaddr,
276 				mapped_rem_addr)) {
277 
278 				memcpy(remote_addr, &rem_info->remote_sockaddr,
279 					sizeof(struct sockaddr_storage));
280 				iwpm_print_sockaddr(remote_addr,
281 						"get_remote_info: Remote sockaddr:");
282 
283 				hlist_del_init(&rem_info->hlist_node);
284 				kfree(rem_info);
285 				ret = 0;
286 				break;
287 			}
288 		}
289 	}
290 get_remote_info_exit:
291 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
292 	return ret;
293 }
294 
295 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
296 					u8 nl_client, gfp_t gfp)
297 {
298 	struct iwpm_nlmsg_request *nlmsg_request = NULL;
299 	unsigned long flags;
300 
301 	nlmsg_request = kzalloc(sizeof(struct iwpm_nlmsg_request), gfp);
302 	if (!nlmsg_request)
303 		return NULL;
304 
305 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
306 	list_add_tail(&nlmsg_request->inprocess_list, &iwpm_nlmsg_req_list);
307 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
308 
309 	kref_init(&nlmsg_request->kref);
310 	kref_get(&nlmsg_request->kref);
311 	nlmsg_request->nlmsg_seq = nlmsg_seq;
312 	nlmsg_request->nl_client = nl_client;
313 	nlmsg_request->request_done = 0;
314 	nlmsg_request->err_code = 0;
315 	sema_init(&nlmsg_request->sem, 1);
316 	down(&nlmsg_request->sem);
317 	return nlmsg_request;
318 }
319 
320 void iwpm_free_nlmsg_request(struct kref *kref)
321 {
322 	struct iwpm_nlmsg_request *nlmsg_request;
323 	unsigned long flags;
324 
325 	nlmsg_request = container_of(kref, struct iwpm_nlmsg_request, kref);
326 
327 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
328 	list_del_init(&nlmsg_request->inprocess_list);
329 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
330 
331 	if (!nlmsg_request->request_done)
332 		pr_debug("%s Freeing incomplete nlmsg request (seq = %u).\n",
333 			__func__, nlmsg_request->nlmsg_seq);
334 	kfree(nlmsg_request);
335 }
336 
337 struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
338 {
339 	struct iwpm_nlmsg_request *nlmsg_request;
340 	struct iwpm_nlmsg_request *found_request = NULL;
341 	unsigned long flags;
342 
343 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
344 	list_for_each_entry(nlmsg_request, &iwpm_nlmsg_req_list,
345 			    inprocess_list) {
346 		if (nlmsg_request->nlmsg_seq == echo_seq) {
347 			found_request = nlmsg_request;
348 			kref_get(&nlmsg_request->kref);
349 			break;
350 		}
351 	}
352 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
353 	return found_request;
354 }
355 
356 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
357 {
358 	int ret;
359 
360 	ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
361 	if (ret) {
362 		ret = -EINVAL;
363 		pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
364 			__func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
365 	} else {
366 		ret = nlmsg_request->err_code;
367 	}
368 	kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
369 	return ret;
370 }
371 
372 int iwpm_get_nlmsg_seq(void)
373 {
374 	return atomic_inc_return(&iwpm_admin.nlmsg_seq);
375 }
376 
377 int iwpm_valid_client(u8 nl_client)
378 {
379 	return iwpm_admin.client_list[nl_client];
380 }
381 
382 void iwpm_set_valid(u8 nl_client, int valid)
383 {
384 	iwpm_admin.client_list[nl_client] = valid;
385 }
386 
387 /* valid client */
388 u32 iwpm_get_registration(u8 nl_client)
389 {
390 	return iwpm_admin.reg_list[nl_client];
391 }
392 
393 /* valid client */
394 void iwpm_set_registration(u8 nl_client, u32 reg)
395 {
396 	iwpm_admin.reg_list[nl_client] = reg;
397 }
398 
399 /* valid client */
400 u32 iwpm_check_registration(u8 nl_client, u32 reg)
401 {
402 	return (iwpm_get_registration(nl_client) & reg);
403 }
404 
405 int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
406 				struct sockaddr_storage *b_sockaddr)
407 {
408 	if (a_sockaddr->ss_family != b_sockaddr->ss_family)
409 		return 1;
410 	if (a_sockaddr->ss_family == AF_INET) {
411 		struct sockaddr_in *a4_sockaddr =
412 			(struct sockaddr_in *)a_sockaddr;
413 		struct sockaddr_in *b4_sockaddr =
414 			(struct sockaddr_in *)b_sockaddr;
415 		if (!memcmp(&a4_sockaddr->sin_addr,
416 			&b4_sockaddr->sin_addr, sizeof(struct in_addr))
417 			&& a4_sockaddr->sin_port == b4_sockaddr->sin_port)
418 				return 0;
419 
420 	} else if (a_sockaddr->ss_family == AF_INET6) {
421 		struct sockaddr_in6 *a6_sockaddr =
422 			(struct sockaddr_in6 *)a_sockaddr;
423 		struct sockaddr_in6 *b6_sockaddr =
424 			(struct sockaddr_in6 *)b_sockaddr;
425 		if (!memcmp(&a6_sockaddr->sin6_addr,
426 			&b6_sockaddr->sin6_addr, sizeof(struct in6_addr))
427 			&& a6_sockaddr->sin6_port == b6_sockaddr->sin6_port)
428 				return 0;
429 
430 	} else {
431 		pr_err("%s: Invalid sockaddr family\n", __func__);
432 	}
433 	return 1;
434 }
435 
436 struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
437 						int nl_client)
438 {
439 	struct sk_buff *skb = NULL;
440 
441 	skb = dev_alloc_skb(IWPM_MSG_SIZE);
442 	if (!skb)
443 		goto create_nlmsg_exit;
444 
445 	if (!(ibnl_put_msg(skb, nlh, 0, 0, nl_client, nl_op,
446 			   NLM_F_REQUEST))) {
447 		pr_warn("%s: Unable to put the nlmsg header\n", __func__);
448 		dev_kfree_skb(skb);
449 		skb = NULL;
450 	}
451 create_nlmsg_exit:
452 	return skb;
453 }
454 
455 int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
456 				   const struct nla_policy *nlmsg_policy,
457 				   struct nlattr *nltb[], const char *msg_type)
458 {
459 	int nlh_len = 0;
460 	int ret;
461 	const char *err_str = "";
462 
463 	ret = nlmsg_validate(cb->nlh, nlh_len, policy_max - 1, nlmsg_policy,
464 			     NULL);
465 	if (ret) {
466 		err_str = "Invalid attribute";
467 		goto parse_nlmsg_error;
468 	}
469 	ret = nlmsg_parse(cb->nlh, nlh_len, nltb, policy_max - 1,
470 			  nlmsg_policy, NULL);
471 	if (ret) {
472 		err_str = "Unable to parse the nlmsg";
473 		goto parse_nlmsg_error;
474 	}
475 	ret = iwpm_validate_nlmsg_attr(nltb, policy_max);
476 	if (ret) {
477 		err_str = "Invalid NULL attribute";
478 		goto parse_nlmsg_error;
479 	}
480 	return 0;
481 parse_nlmsg_error:
482 	pr_warn("%s: %s (msg type %s ret = %d)\n",
483 			__func__, err_str, msg_type, ret);
484 	return ret;
485 }
486 
487 void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg)
488 {
489 	struct sockaddr_in6 *sockaddr_v6;
490 	struct sockaddr_in *sockaddr_v4;
491 
492 	switch (sockaddr->ss_family) {
493 	case AF_INET:
494 		sockaddr_v4 = (struct sockaddr_in *)sockaddr;
495 		pr_debug("%s IPV4 %pI4: %u(0x%04X)\n",
496 			msg, &sockaddr_v4->sin_addr,
497 			ntohs(sockaddr_v4->sin_port),
498 			ntohs(sockaddr_v4->sin_port));
499 		break;
500 	case AF_INET6:
501 		sockaddr_v6 = (struct sockaddr_in6 *)sockaddr;
502 		pr_debug("%s IPV6 %pI6: %u(0x%04X)\n",
503 			msg, &sockaddr_v6->sin6_addr,
504 			ntohs(sockaddr_v6->sin6_port),
505 			ntohs(sockaddr_v6->sin6_port));
506 		break;
507 	default:
508 		break;
509 	}
510 }
511 
512 static u32 iwpm_ipv6_jhash(struct sockaddr_in6 *ipv6_sockaddr)
513 {
514 	u32 ipv6_hash = jhash(&ipv6_sockaddr->sin6_addr, sizeof(struct in6_addr), 0);
515 	u32 hash = jhash_2words(ipv6_hash, (__force u32) ipv6_sockaddr->sin6_port, 0);
516 	return hash;
517 }
518 
519 static u32 iwpm_ipv4_jhash(struct sockaddr_in *ipv4_sockaddr)
520 {
521 	u32 ipv4_hash = jhash(&ipv4_sockaddr->sin_addr, sizeof(struct in_addr), 0);
522 	u32 hash = jhash_2words(ipv4_hash, (__force u32) ipv4_sockaddr->sin_port, 0);
523 	return hash;
524 }
525 
526 static int get_hash_bucket(struct sockaddr_storage *a_sockaddr,
527 				struct sockaddr_storage *b_sockaddr, u32 *hash)
528 {
529 	u32 a_hash, b_hash;
530 
531 	if (a_sockaddr->ss_family == AF_INET) {
532 		a_hash = iwpm_ipv4_jhash((struct sockaddr_in *) a_sockaddr);
533 		b_hash = iwpm_ipv4_jhash((struct sockaddr_in *) b_sockaddr);
534 
535 	} else if (a_sockaddr->ss_family == AF_INET6) {
536 		a_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) a_sockaddr);
537 		b_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) b_sockaddr);
538 	} else {
539 		pr_err("%s: Invalid sockaddr family\n", __func__);
540 		return -EINVAL;
541 	}
542 
543 	if (a_hash == b_hash) /* if port mapper isn't available */
544 		*hash = a_hash;
545 	else
546 		*hash = jhash_2words(a_hash, b_hash, 0);
547 	return 0;
548 }
549 
550 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage
551 				*local_sockaddr, struct sockaddr_storage
552 				*mapped_sockaddr)
553 {
554 	u32 hash;
555 	int ret;
556 
557 	ret = get_hash_bucket(local_sockaddr, mapped_sockaddr, &hash);
558 	if (ret)
559 		return NULL;
560 	return &iwpm_hash_bucket[hash & IWPM_MAPINFO_HASH_MASK];
561 }
562 
563 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage
564 				*mapped_loc_sockaddr, struct sockaddr_storage
565 				*mapped_rem_sockaddr)
566 {
567 	u32 hash;
568 	int ret;
569 
570 	ret = get_hash_bucket(mapped_loc_sockaddr, mapped_rem_sockaddr, &hash);
571 	if (ret)
572 		return NULL;
573 	return &iwpm_reminfo_bucket[hash & IWPM_REMINFO_HASH_MASK];
574 }
575 
576 static int send_mapinfo_num(u32 mapping_num, u8 nl_client, int iwpm_pid)
577 {
578 	struct sk_buff *skb = NULL;
579 	struct nlmsghdr *nlh;
580 	u32 msg_seq;
581 	const char *err_str = "";
582 	int ret = -EINVAL;
583 
584 	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_MAPINFO_NUM, &nlh, nl_client);
585 	if (!skb) {
586 		err_str = "Unable to create a nlmsg";
587 		goto mapinfo_num_error;
588 	}
589 	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
590 	msg_seq = 0;
591 	err_str = "Unable to put attribute of mapinfo number nlmsg";
592 	ret = ibnl_put_attr(skb, nlh, sizeof(u32), &msg_seq, IWPM_NLA_MAPINFO_SEQ);
593 	if (ret)
594 		goto mapinfo_num_error;
595 	ret = ibnl_put_attr(skb, nlh, sizeof(u32),
596 				&mapping_num, IWPM_NLA_MAPINFO_SEND_NUM);
597 	if (ret)
598 		goto mapinfo_num_error;
599 
600 	nlmsg_end(skb, nlh);
601 
602 	ret = rdma_nl_unicast(skb, iwpm_pid);
603 	if (ret) {
604 		skb = NULL;
605 		err_str = "Unable to send a nlmsg";
606 		goto mapinfo_num_error;
607 	}
608 	pr_debug("%s: Sent mapping number = %d\n", __func__, mapping_num);
609 	return 0;
610 mapinfo_num_error:
611 	pr_info("%s: %s\n", __func__, err_str);
612 	if (skb)
613 		dev_kfree_skb(skb);
614 	return ret;
615 }
616 
617 static int send_nlmsg_done(struct sk_buff *skb, u8 nl_client, int iwpm_pid)
618 {
619 	struct nlmsghdr *nlh = NULL;
620 	int ret = 0;
621 
622 	if (!skb)
623 		return ret;
624 	if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
625 			   RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
626 		pr_warn("%s Unable to put NLMSG_DONE\n", __func__);
627 		dev_kfree_skb(skb);
628 		return -ENOMEM;
629 	}
630 	nlh->nlmsg_type = NLMSG_DONE;
631 	ret = rdma_nl_unicast(skb, iwpm_pid);
632 	if (ret)
633 		pr_warn("%s Unable to send a nlmsg\n", __func__);
634 	return ret;
635 }
636 
637 int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid)
638 {
639 	struct iwpm_mapping_info *map_info;
640 	struct sk_buff *skb = NULL;
641 	struct nlmsghdr *nlh;
642 	int skb_num = 0, mapping_num = 0;
643 	int i = 0, nlmsg_bytes = 0;
644 	unsigned long flags;
645 	const char *err_str = "";
646 	int ret;
647 
648 	skb = dev_alloc_skb(NLMSG_GOODSIZE);
649 	if (!skb) {
650 		ret = -ENOMEM;
651 		err_str = "Unable to allocate skb";
652 		goto send_mapping_info_exit;
653 	}
654 	skb_num++;
655 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
656 	ret = -EINVAL;
657 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
658 		hlist_for_each_entry(map_info, &iwpm_hash_bucket[i],
659 				     hlist_node) {
660 			if (map_info->nl_client != nl_client)
661 				continue;
662 			nlh = NULL;
663 			if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
664 					RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
665 				ret = -ENOMEM;
666 				err_str = "Unable to put the nlmsg header";
667 				goto send_mapping_info_unlock;
668 			}
669 			err_str = "Unable to put attribute of the nlmsg";
670 			ret = ibnl_put_attr(skb, nlh,
671 					sizeof(struct sockaddr_storage),
672 					&map_info->local_sockaddr,
673 					IWPM_NLA_MAPINFO_LOCAL_ADDR);
674 			if (ret)
675 				goto send_mapping_info_unlock;
676 
677 			ret = ibnl_put_attr(skb, nlh,
678 					sizeof(struct sockaddr_storage),
679 					&map_info->mapped_sockaddr,
680 					IWPM_NLA_MAPINFO_MAPPED_ADDR);
681 			if (ret)
682 				goto send_mapping_info_unlock;
683 
684 			nlmsg_end(skb, nlh);
685 
686 			iwpm_print_sockaddr(&map_info->local_sockaddr,
687 				"send_mapping_info: Local sockaddr:");
688 			iwpm_print_sockaddr(&map_info->mapped_sockaddr,
689 				"send_mapping_info: Mapped local sockaddr:");
690 			mapping_num++;
691 			nlmsg_bytes += nlh->nlmsg_len;
692 
693 			/* check if all mappings can fit in one skb */
694 			if (NLMSG_GOODSIZE - nlmsg_bytes < nlh->nlmsg_len * 2) {
695 				/* and leave room for NLMSG_DONE */
696 				nlmsg_bytes = 0;
697 				skb_num++;
698 				spin_unlock_irqrestore(&iwpm_mapinfo_lock,
699 						       flags);
700 				/* send the skb */
701 				ret = send_nlmsg_done(skb, nl_client, iwpm_pid);
702 				skb = NULL;
703 				if (ret) {
704 					err_str = "Unable to send map info";
705 					goto send_mapping_info_exit;
706 				}
707 				if (skb_num == IWPM_MAPINFO_SKB_COUNT) {
708 					ret = -ENOMEM;
709 					err_str = "Insufficient skbs for map info";
710 					goto send_mapping_info_exit;
711 				}
712 				skb = dev_alloc_skb(NLMSG_GOODSIZE);
713 				if (!skb) {
714 					ret = -ENOMEM;
715 					err_str = "Unable to allocate skb";
716 					goto send_mapping_info_exit;
717 				}
718 				spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
719 			}
720 		}
721 	}
722 send_mapping_info_unlock:
723 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
724 send_mapping_info_exit:
725 	if (ret) {
726 		pr_warn("%s: %s (ret = %d)\n", __func__, err_str, ret);
727 		if (skb)
728 			dev_kfree_skb(skb);
729 		return ret;
730 	}
731 	send_nlmsg_done(skb, nl_client, iwpm_pid);
732 	return send_mapinfo_num(mapping_num, nl_client, iwpm_pid);
733 }
734 
735 int iwpm_mapinfo_available(void)
736 {
737 	unsigned long flags;
738 	int full_bucket = 0, i = 0;
739 
740 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
741 	if (iwpm_hash_bucket) {
742 		for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
743 			if (!hlist_empty(&iwpm_hash_bucket[i])) {
744 				full_bucket = 1;
745 				break;
746 			}
747 		}
748 	}
749 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
750 	return full_bucket;
751 }
752