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 struct iwpm_admin_data iwpm_admin;
52 
53 /**
54  * iwpm_init - Allocate resources for the iwarp port mapper
55  * @nl_client: The index of the netlink client
56  *
57  * Should be called when network interface goes up.
58  */
59 int iwpm_init(u8 nl_client)
60 {
61 	iwpm_hash_bucket = kcalloc(IWPM_MAPINFO_HASH_SIZE,
62 				   sizeof(struct hlist_head), GFP_KERNEL);
63 	if (!iwpm_hash_bucket)
64 		return -ENOMEM;
65 
66 	iwpm_reminfo_bucket = kcalloc(IWPM_REMINFO_HASH_SIZE,
67 				      sizeof(struct hlist_head), GFP_KERNEL);
68 	if (!iwpm_reminfo_bucket) {
69 		kfree(iwpm_hash_bucket);
70 		return -ENOMEM;
71 	}
72 
73 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
74 	pr_debug("%s: Mapinfo and reminfo tables are created\n", __func__);
75 	return 0;
76 }
77 
78 static void free_hash_bucket(void);
79 static void free_reminfo_bucket(void);
80 
81 /**
82  * iwpm_exit - Deallocate resources for the iwarp port mapper
83  * @nl_client: The index of the netlink client
84  *
85  * Should be called when network interface goes down.
86  */
87 int iwpm_exit(u8 nl_client)
88 {
89 	free_hash_bucket();
90 	free_reminfo_bucket();
91 	pr_debug("%s: Resources are destroyed\n", __func__);
92 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
93 	return 0;
94 }
95 
96 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage *,
97 					       struct sockaddr_storage *);
98 
99 /**
100  * iwpm_create_mapinfo - Store local and mapped IPv4/IPv6 address
101  *                       info in a hash table
102  * @local_sockaddr: Local ip/tcp address
103  * @mapped_sockaddr: Mapped local ip/tcp address
104  * @nl_client: The index of the netlink client
105  * @map_flags: IWPM mapping flags
106  */
107 int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
108 			struct sockaddr_storage *mapped_sockaddr,
109 			u8 nl_client, u32 map_flags)
110 {
111 	struct hlist_head *hash_bucket_head = NULL;
112 	struct iwpm_mapping_info *map_info;
113 	unsigned long flags;
114 	int ret = -EINVAL;
115 
116 	map_info = kzalloc(sizeof(struct iwpm_mapping_info), GFP_KERNEL);
117 	if (!map_info)
118 		return -ENOMEM;
119 
120 	memcpy(&map_info->local_sockaddr, local_sockaddr,
121 	       sizeof(struct sockaddr_storage));
122 	memcpy(&map_info->mapped_sockaddr, mapped_sockaddr,
123 	       sizeof(struct sockaddr_storage));
124 	map_info->nl_client = nl_client;
125 	map_info->map_flags = map_flags;
126 
127 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
128 	if (iwpm_hash_bucket) {
129 		hash_bucket_head = get_mapinfo_hash_bucket(
130 					&map_info->local_sockaddr,
131 					&map_info->mapped_sockaddr);
132 		if (hash_bucket_head) {
133 			hlist_add_head(&map_info->hlist_node, hash_bucket_head);
134 			ret = 0;
135 		}
136 	}
137 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
138 
139 	if (!hash_bucket_head)
140 		kfree(map_info);
141 	return ret;
142 }
143 
144 /**
145  * iwpm_remove_mapinfo - Remove local and mapped IPv4/IPv6 address
146  *                       info from the hash table
147  * @local_sockaddr: Local ip/tcp address
148  * @mapped_local_addr: Mapped local ip/tcp address
149  *
150  * Returns err code if mapping info is not found in the hash table,
151  * otherwise returns 0
152  */
153 int iwpm_remove_mapinfo(struct sockaddr_storage *local_sockaddr,
154 			struct sockaddr_storage *mapped_local_addr)
155 {
156 	struct hlist_node *tmp_hlist_node;
157 	struct hlist_head *hash_bucket_head;
158 	struct iwpm_mapping_info *map_info = NULL;
159 	unsigned long flags;
160 	int ret = -EINVAL;
161 
162 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
163 	if (iwpm_hash_bucket) {
164 		hash_bucket_head = get_mapinfo_hash_bucket(
165 					local_sockaddr,
166 					mapped_local_addr);
167 		if (!hash_bucket_head)
168 			goto remove_mapinfo_exit;
169 
170 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
171 					hash_bucket_head, hlist_node) {
172 
173 			if (!iwpm_compare_sockaddr(&map_info->mapped_sockaddr,
174 						mapped_local_addr)) {
175 
176 				hlist_del_init(&map_info->hlist_node);
177 				kfree(map_info);
178 				ret = 0;
179 				break;
180 			}
181 		}
182 	}
183 remove_mapinfo_exit:
184 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
185 	return ret;
186 }
187 
188 static void free_hash_bucket(void)
189 {
190 	struct hlist_node *tmp_hlist_node;
191 	struct iwpm_mapping_info *map_info;
192 	unsigned long flags;
193 	int i;
194 
195 	/* remove all the mapinfo data from the list */
196 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
197 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
198 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
199 			&iwpm_hash_bucket[i], hlist_node) {
200 
201 				hlist_del_init(&map_info->hlist_node);
202 				kfree(map_info);
203 			}
204 	}
205 	/* free the hash list */
206 	kfree(iwpm_hash_bucket);
207 	iwpm_hash_bucket = NULL;
208 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
209 }
210 
211 static void free_reminfo_bucket(void)
212 {
213 	struct hlist_node *tmp_hlist_node;
214 	struct iwpm_remote_info *rem_info;
215 	unsigned long flags;
216 	int i;
217 
218 	/* remove all the remote info from the list */
219 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
220 	for (i = 0; i < IWPM_REMINFO_HASH_SIZE; i++) {
221 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
222 			&iwpm_reminfo_bucket[i], hlist_node) {
223 
224 				hlist_del_init(&rem_info->hlist_node);
225 				kfree(rem_info);
226 			}
227 	}
228 	/* free the hash list */
229 	kfree(iwpm_reminfo_bucket);
230 	iwpm_reminfo_bucket = NULL;
231 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
232 }
233 
234 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage *,
235 						struct sockaddr_storage *);
236 
237 void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
238 {
239 	struct hlist_head *hash_bucket_head;
240 	unsigned long flags;
241 
242 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
243 	if (iwpm_reminfo_bucket) {
244 		hash_bucket_head = get_reminfo_hash_bucket(
245 					&rem_info->mapped_loc_sockaddr,
246 					&rem_info->mapped_rem_sockaddr);
247 		if (hash_bucket_head)
248 			hlist_add_head(&rem_info->hlist_node, hash_bucket_head);
249 	}
250 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
251 }
252 
253 /**
254  * iwpm_get_remote_info - Get the remote connecting peer address info
255  *
256  * @mapped_loc_addr: Mapped local address of the listening peer
257  * @mapped_rem_addr: Mapped remote address of the connecting peer
258  * @remote_addr: To store the remote address of the connecting peer
259  * @nl_client: The index of the netlink client
260  *
261  * The remote address info is retrieved and provided to the client in
262  * the remote_addr. After that it is removed from the hash table
263  */
264 int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
265 			 struct sockaddr_storage *mapped_rem_addr,
266 			 struct sockaddr_storage *remote_addr,
267 			 u8 nl_client)
268 {
269 	struct hlist_node *tmp_hlist_node;
270 	struct hlist_head *hash_bucket_head;
271 	struct iwpm_remote_info *rem_info = NULL;
272 	unsigned long flags;
273 	int ret = -EINVAL;
274 
275 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
276 	if (iwpm_reminfo_bucket) {
277 		hash_bucket_head = get_reminfo_hash_bucket(
278 					mapped_loc_addr,
279 					mapped_rem_addr);
280 		if (!hash_bucket_head)
281 			goto get_remote_info_exit;
282 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
283 					hash_bucket_head, hlist_node) {
284 
285 			if (!iwpm_compare_sockaddr(&rem_info->mapped_loc_sockaddr,
286 				mapped_loc_addr) &&
287 				!iwpm_compare_sockaddr(&rem_info->mapped_rem_sockaddr,
288 				mapped_rem_addr)) {
289 
290 				memcpy(remote_addr, &rem_info->remote_sockaddr,
291 					sizeof(struct sockaddr_storage));
292 				iwpm_print_sockaddr(remote_addr,
293 						"get_remote_info: Remote sockaddr:");
294 
295 				hlist_del_init(&rem_info->hlist_node);
296 				kfree(rem_info);
297 				ret = 0;
298 				break;
299 			}
300 		}
301 	}
302 get_remote_info_exit:
303 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
304 	return ret;
305 }
306 
307 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
308 					u8 nl_client, gfp_t gfp)
309 {
310 	struct iwpm_nlmsg_request *nlmsg_request = NULL;
311 	unsigned long flags;
312 
313 	nlmsg_request = kzalloc(sizeof(struct iwpm_nlmsg_request), gfp);
314 	if (!nlmsg_request)
315 		return NULL;
316 
317 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
318 	list_add_tail(&nlmsg_request->inprocess_list, &iwpm_nlmsg_req_list);
319 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
320 
321 	kref_init(&nlmsg_request->kref);
322 	kref_get(&nlmsg_request->kref);
323 	nlmsg_request->nlmsg_seq = nlmsg_seq;
324 	nlmsg_request->nl_client = nl_client;
325 	nlmsg_request->request_done = 0;
326 	nlmsg_request->err_code = 0;
327 	sema_init(&nlmsg_request->sem, 1);
328 	down(&nlmsg_request->sem);
329 	return nlmsg_request;
330 }
331 
332 void iwpm_free_nlmsg_request(struct kref *kref)
333 {
334 	struct iwpm_nlmsg_request *nlmsg_request;
335 	unsigned long flags;
336 
337 	nlmsg_request = container_of(kref, struct iwpm_nlmsg_request, kref);
338 
339 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
340 	list_del_init(&nlmsg_request->inprocess_list);
341 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
342 
343 	if (!nlmsg_request->request_done)
344 		pr_debug("%s Freeing incomplete nlmsg request (seq = %u).\n",
345 			__func__, nlmsg_request->nlmsg_seq);
346 	kfree(nlmsg_request);
347 }
348 
349 struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
350 {
351 	struct iwpm_nlmsg_request *nlmsg_request;
352 	struct iwpm_nlmsg_request *found_request = NULL;
353 	unsigned long flags;
354 
355 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
356 	list_for_each_entry(nlmsg_request, &iwpm_nlmsg_req_list,
357 			    inprocess_list) {
358 		if (nlmsg_request->nlmsg_seq == echo_seq) {
359 			found_request = nlmsg_request;
360 			kref_get(&nlmsg_request->kref);
361 			break;
362 		}
363 	}
364 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
365 	return found_request;
366 }
367 
368 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
369 {
370 	int ret;
371 
372 	ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
373 	if (ret) {
374 		ret = -EINVAL;
375 		pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
376 			__func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
377 	} else {
378 		ret = nlmsg_request->err_code;
379 	}
380 	kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
381 	return ret;
382 }
383 
384 int iwpm_get_nlmsg_seq(void)
385 {
386 	return atomic_inc_return(&iwpm_admin.nlmsg_seq);
387 }
388 
389 /* valid client */
390 u32 iwpm_get_registration(u8 nl_client)
391 {
392 	return iwpm_admin.reg_list[nl_client];
393 }
394 
395 /* valid client */
396 void iwpm_set_registration(u8 nl_client, u32 reg)
397 {
398 	iwpm_admin.reg_list[nl_client] = reg;
399 }
400 
401 /* valid client */
402 u32 iwpm_check_registration(u8 nl_client, u32 reg)
403 {
404 	return (iwpm_get_registration(nl_client) & reg);
405 }
406 
407 int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
408 				struct sockaddr_storage *b_sockaddr)
409 {
410 	if (a_sockaddr->ss_family != b_sockaddr->ss_family)
411 		return 1;
412 	if (a_sockaddr->ss_family == AF_INET) {
413 		struct sockaddr_in *a4_sockaddr =
414 			(struct sockaddr_in *)a_sockaddr;
415 		struct sockaddr_in *b4_sockaddr =
416 			(struct sockaddr_in *)b_sockaddr;
417 		if (!memcmp(&a4_sockaddr->sin_addr,
418 			&b4_sockaddr->sin_addr, sizeof(struct in_addr))
419 			&& a4_sockaddr->sin_port == b4_sockaddr->sin_port)
420 				return 0;
421 
422 	} else if (a_sockaddr->ss_family == AF_INET6) {
423 		struct sockaddr_in6 *a6_sockaddr =
424 			(struct sockaddr_in6 *)a_sockaddr;
425 		struct sockaddr_in6 *b6_sockaddr =
426 			(struct sockaddr_in6 *)b_sockaddr;
427 		if (!memcmp(&a6_sockaddr->sin6_addr,
428 			&b6_sockaddr->sin6_addr, sizeof(struct in6_addr))
429 			&& a6_sockaddr->sin6_port == b6_sockaddr->sin6_port)
430 				return 0;
431 
432 	} else {
433 		pr_err("%s: Invalid sockaddr family\n", __func__);
434 	}
435 	return 1;
436 }
437 
438 struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
439 						int nl_client)
440 {
441 	struct sk_buff *skb = NULL;
442 
443 	skb = dev_alloc_skb(IWPM_MSG_SIZE);
444 	if (!skb)
445 		goto create_nlmsg_exit;
446 
447 	if (!(ibnl_put_msg(skb, nlh, 0, 0, nl_client, nl_op,
448 			   NLM_F_REQUEST))) {
449 		pr_warn("%s: Unable to put the nlmsg header\n", __func__);
450 		dev_kfree_skb(skb);
451 		skb = NULL;
452 	}
453 create_nlmsg_exit:
454 	return skb;
455 }
456 
457 int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
458 				   const struct nla_policy *nlmsg_policy,
459 				   struct nlattr *nltb[], const char *msg_type)
460 {
461 	int nlh_len = 0;
462 	int ret;
463 	const char *err_str = "";
464 
465 	ret = nlmsg_validate_deprecated(cb->nlh, nlh_len, policy_max - 1,
466 					nlmsg_policy, NULL);
467 	if (ret) {
468 		err_str = "Invalid attribute";
469 		goto parse_nlmsg_error;
470 	}
471 	ret = nlmsg_parse_deprecated(cb->nlh, nlh_len, nltb, policy_max - 1,
472 				     nlmsg_policy, NULL);
473 	if (ret) {
474 		err_str = "Unable to parse the nlmsg";
475 		goto parse_nlmsg_error;
476 	}
477 	ret = iwpm_validate_nlmsg_attr(nltb, policy_max);
478 	if (ret) {
479 		err_str = "Invalid NULL attribute";
480 		goto parse_nlmsg_error;
481 	}
482 	return 0;
483 parse_nlmsg_error:
484 	pr_warn("%s: %s (msg type %s ret = %d)\n",
485 			__func__, err_str, msg_type, ret);
486 	return ret;
487 }
488 
489 void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg)
490 {
491 	struct sockaddr_in6 *sockaddr_v6;
492 	struct sockaddr_in *sockaddr_v4;
493 
494 	switch (sockaddr->ss_family) {
495 	case AF_INET:
496 		sockaddr_v4 = (struct sockaddr_in *)sockaddr;
497 		pr_debug("%s IPV4 %pI4: %u(0x%04X)\n",
498 			msg, &sockaddr_v4->sin_addr,
499 			ntohs(sockaddr_v4->sin_port),
500 			ntohs(sockaddr_v4->sin_port));
501 		break;
502 	case AF_INET6:
503 		sockaddr_v6 = (struct sockaddr_in6 *)sockaddr;
504 		pr_debug("%s IPV6 %pI6: %u(0x%04X)\n",
505 			msg, &sockaddr_v6->sin6_addr,
506 			ntohs(sockaddr_v6->sin6_port),
507 			ntohs(sockaddr_v6->sin6_port));
508 		break;
509 	default:
510 		break;
511 	}
512 }
513 
514 static u32 iwpm_ipv6_jhash(struct sockaddr_in6 *ipv6_sockaddr)
515 {
516 	u32 ipv6_hash = jhash(&ipv6_sockaddr->sin6_addr, sizeof(struct in6_addr), 0);
517 	u32 hash = jhash_2words(ipv6_hash, (__force u32) ipv6_sockaddr->sin6_port, 0);
518 	return hash;
519 }
520 
521 static u32 iwpm_ipv4_jhash(struct sockaddr_in *ipv4_sockaddr)
522 {
523 	u32 ipv4_hash = jhash(&ipv4_sockaddr->sin_addr, sizeof(struct in_addr), 0);
524 	u32 hash = jhash_2words(ipv4_hash, (__force u32) ipv4_sockaddr->sin_port, 0);
525 	return hash;
526 }
527 
528 static int get_hash_bucket(struct sockaddr_storage *a_sockaddr,
529 				struct sockaddr_storage *b_sockaddr, u32 *hash)
530 {
531 	u32 a_hash, b_hash;
532 
533 	if (a_sockaddr->ss_family == AF_INET) {
534 		a_hash = iwpm_ipv4_jhash((struct sockaddr_in *) a_sockaddr);
535 		b_hash = iwpm_ipv4_jhash((struct sockaddr_in *) b_sockaddr);
536 
537 	} else if (a_sockaddr->ss_family == AF_INET6) {
538 		a_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) a_sockaddr);
539 		b_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) b_sockaddr);
540 	} else {
541 		pr_err("%s: Invalid sockaddr family\n", __func__);
542 		return -EINVAL;
543 	}
544 
545 	if (a_hash == b_hash) /* if port mapper isn't available */
546 		*hash = a_hash;
547 	else
548 		*hash = jhash_2words(a_hash, b_hash, 0);
549 	return 0;
550 }
551 
552 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage
553 				*local_sockaddr, struct sockaddr_storage
554 				*mapped_sockaddr)
555 {
556 	u32 hash;
557 	int ret;
558 
559 	ret = get_hash_bucket(local_sockaddr, mapped_sockaddr, &hash);
560 	if (ret)
561 		return NULL;
562 	return &iwpm_hash_bucket[hash & IWPM_MAPINFO_HASH_MASK];
563 }
564 
565 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage
566 				*mapped_loc_sockaddr, struct sockaddr_storage
567 				*mapped_rem_sockaddr)
568 {
569 	u32 hash;
570 	int ret;
571 
572 	ret = get_hash_bucket(mapped_loc_sockaddr, mapped_rem_sockaddr, &hash);
573 	if (ret)
574 		return NULL;
575 	return &iwpm_reminfo_bucket[hash & IWPM_REMINFO_HASH_MASK];
576 }
577 
578 static int send_mapinfo_num(u32 mapping_num, u8 nl_client, int iwpm_pid)
579 {
580 	struct sk_buff *skb = NULL;
581 	struct nlmsghdr *nlh;
582 	u32 msg_seq;
583 	const char *err_str = "";
584 	int ret = -EINVAL;
585 
586 	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_MAPINFO_NUM, &nlh, nl_client);
587 	if (!skb) {
588 		err_str = "Unable to create a nlmsg";
589 		goto mapinfo_num_error;
590 	}
591 	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
592 	msg_seq = 0;
593 	err_str = "Unable to put attribute of mapinfo number nlmsg";
594 	ret = ibnl_put_attr(skb, nlh, sizeof(u32), &msg_seq, IWPM_NLA_MAPINFO_SEQ);
595 	if (ret)
596 		goto mapinfo_num_error;
597 	ret = ibnl_put_attr(skb, nlh, sizeof(u32),
598 				&mapping_num, IWPM_NLA_MAPINFO_SEND_NUM);
599 	if (ret)
600 		goto mapinfo_num_error;
601 
602 	nlmsg_end(skb, nlh);
603 
604 	ret = rdma_nl_unicast(&init_net, skb, iwpm_pid);
605 	if (ret) {
606 		skb = NULL;
607 		err_str = "Unable to send a nlmsg";
608 		goto mapinfo_num_error;
609 	}
610 	pr_debug("%s: Sent mapping number = %u\n", __func__, mapping_num);
611 	return 0;
612 mapinfo_num_error:
613 	pr_info("%s: %s\n", __func__, err_str);
614 	dev_kfree_skb(skb);
615 	return ret;
616 }
617 
618 static int send_nlmsg_done(struct sk_buff *skb, u8 nl_client, int iwpm_pid)
619 {
620 	struct nlmsghdr *nlh = NULL;
621 	int ret = 0;
622 
623 	if (!skb)
624 		return ret;
625 	if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
626 			   RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
627 		pr_warn("%s Unable to put NLMSG_DONE\n", __func__);
628 		dev_kfree_skb(skb);
629 		return -ENOMEM;
630 	}
631 	nlh->nlmsg_type = NLMSG_DONE;
632 	ret = rdma_nl_unicast(&init_net, skb, iwpm_pid);
633 	if (ret)
634 		pr_warn("%s Unable to send a nlmsg\n", __func__);
635 	return ret;
636 }
637 
638 int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid)
639 {
640 	struct iwpm_mapping_info *map_info;
641 	struct sk_buff *skb = NULL;
642 	struct nlmsghdr *nlh;
643 	int skb_num = 0, mapping_num = 0;
644 	int i = 0, nlmsg_bytes = 0;
645 	unsigned long flags;
646 	const char *err_str = "";
647 	int ret;
648 
649 	skb = dev_alloc_skb(NLMSG_GOODSIZE);
650 	if (!skb) {
651 		ret = -ENOMEM;
652 		err_str = "Unable to allocate skb";
653 		goto send_mapping_info_exit;
654 	}
655 	skb_num++;
656 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
657 	ret = -EINVAL;
658 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
659 		hlist_for_each_entry(map_info, &iwpm_hash_bucket[i],
660 				     hlist_node) {
661 			if (map_info->nl_client != nl_client)
662 				continue;
663 			nlh = NULL;
664 			if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
665 					RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
666 				ret = -ENOMEM;
667 				err_str = "Unable to put the nlmsg header";
668 				goto send_mapping_info_unlock;
669 			}
670 			err_str = "Unable to put attribute of the nlmsg";
671 			ret = ibnl_put_attr(skb, nlh,
672 					sizeof(struct sockaddr_storage),
673 					&map_info->local_sockaddr,
674 					IWPM_NLA_MAPINFO_LOCAL_ADDR);
675 			if (ret)
676 				goto send_mapping_info_unlock;
677 
678 			ret = ibnl_put_attr(skb, nlh,
679 					sizeof(struct sockaddr_storage),
680 					&map_info->mapped_sockaddr,
681 					IWPM_NLA_MAPINFO_MAPPED_ADDR);
682 			if (ret)
683 				goto send_mapping_info_unlock;
684 
685 			if (iwpm_ulib_version > IWPM_UABI_VERSION_MIN) {
686 				ret = ibnl_put_attr(skb, nlh, sizeof(u32),
687 						&map_info->map_flags,
688 						IWPM_NLA_MAPINFO_FLAGS);
689 				if (ret)
690 					goto send_mapping_info_unlock;
691 			}
692 
693 			nlmsg_end(skb, nlh);
694 
695 			iwpm_print_sockaddr(&map_info->local_sockaddr,
696 				"send_mapping_info: Local sockaddr:");
697 			iwpm_print_sockaddr(&map_info->mapped_sockaddr,
698 				"send_mapping_info: Mapped local sockaddr:");
699 			mapping_num++;
700 			nlmsg_bytes += nlh->nlmsg_len;
701 
702 			/* check if all mappings can fit in one skb */
703 			if (NLMSG_GOODSIZE - nlmsg_bytes < nlh->nlmsg_len * 2) {
704 				/* and leave room for NLMSG_DONE */
705 				nlmsg_bytes = 0;
706 				skb_num++;
707 				spin_unlock_irqrestore(&iwpm_mapinfo_lock,
708 						       flags);
709 				/* send the skb */
710 				ret = send_nlmsg_done(skb, nl_client, iwpm_pid);
711 				skb = NULL;
712 				if (ret) {
713 					err_str = "Unable to send map info";
714 					goto send_mapping_info_exit;
715 				}
716 				if (skb_num == IWPM_MAPINFO_SKB_COUNT) {
717 					ret = -ENOMEM;
718 					err_str = "Insufficient skbs for map info";
719 					goto send_mapping_info_exit;
720 				}
721 				skb = dev_alloc_skb(NLMSG_GOODSIZE);
722 				if (!skb) {
723 					ret = -ENOMEM;
724 					err_str = "Unable to allocate skb";
725 					goto send_mapping_info_exit;
726 				}
727 				spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
728 			}
729 		}
730 	}
731 send_mapping_info_unlock:
732 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
733 send_mapping_info_exit:
734 	if (ret) {
735 		pr_warn("%s: %s (ret = %d)\n", __func__, err_str, ret);
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 
761 int iwpm_send_hello(u8 nl_client, int iwpm_pid, u16 abi_version)
762 {
763 	struct sk_buff *skb = NULL;
764 	struct nlmsghdr *nlh;
765 	const char *err_str = "";
766 	int ret = -EINVAL;
767 
768 	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_HELLO, &nlh, nl_client);
769 	if (!skb) {
770 		err_str = "Unable to create a nlmsg";
771 		goto hello_num_error;
772 	}
773 	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
774 	err_str = "Unable to put attribute of abi_version into nlmsg";
775 	ret = ibnl_put_attr(skb, nlh, sizeof(u16), &abi_version,
776 			    IWPM_NLA_HELLO_ABI_VERSION);
777 	if (ret)
778 		goto hello_num_error;
779 	nlmsg_end(skb, nlh);
780 
781 	ret = rdma_nl_unicast(&init_net, skb, iwpm_pid);
782 	if (ret) {
783 		skb = NULL;
784 		err_str = "Unable to send a nlmsg";
785 		goto hello_num_error;
786 	}
787 	pr_debug("%s: Sent hello abi_version = %u\n", __func__, abi_version);
788 	return 0;
789 hello_num_error:
790 	pr_info("%s: %s\n", __func__, err_str);
791 	dev_kfree_skb(skb);
792 	return ret;
793 }
794