xref: /linux/drivers/infiniband/core/iwpm_util.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
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 			goto init_exit;
66 		}
67 		iwpm_reminfo_bucket = kzalloc(IWPM_REMINFO_HASH_SIZE *
68 					sizeof(struct hlist_head), GFP_KERNEL);
69 		if (!iwpm_reminfo_bucket) {
70 			kfree(iwpm_hash_bucket);
71 			ret = -ENOMEM;
72 			goto init_exit;
73 		}
74 	}
75 	atomic_inc(&iwpm_admin.refcount);
76 init_exit:
77 	mutex_unlock(&iwpm_admin_lock);
78 	if (!ret) {
79 		iwpm_set_valid(nl_client, 1);
80 		iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
81 		pr_debug("%s: Mapinfo and reminfo tables are created\n",
82 				__func__);
83 	}
84 	return ret;
85 }
86 EXPORT_SYMBOL(iwpm_init);
87 
88 static void free_hash_bucket(void);
89 static void free_reminfo_bucket(void);
90 
91 int iwpm_exit(u8 nl_client)
92 {
93 
94 	if (!iwpm_valid_client(nl_client))
95 		return -EINVAL;
96 	mutex_lock(&iwpm_admin_lock);
97 	if (atomic_read(&iwpm_admin.refcount) == 0) {
98 		mutex_unlock(&iwpm_admin_lock);
99 		pr_err("%s Incorrect usage - negative refcount\n", __func__);
100 		return -EINVAL;
101 	}
102 	if (atomic_dec_and_test(&iwpm_admin.refcount)) {
103 		free_hash_bucket();
104 		free_reminfo_bucket();
105 		pr_debug("%s: Resources are destroyed\n", __func__);
106 	}
107 	mutex_unlock(&iwpm_admin_lock);
108 	iwpm_set_valid(nl_client, 0);
109 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
110 	return 0;
111 }
112 EXPORT_SYMBOL(iwpm_exit);
113 
114 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage *,
115 					       struct sockaddr_storage *);
116 
117 int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
118 			struct sockaddr_storage *mapped_sockaddr,
119 			u8 nl_client)
120 {
121 	struct hlist_head *hash_bucket_head;
122 	struct iwpm_mapping_info *map_info;
123 	unsigned long flags;
124 	int ret = -EINVAL;
125 
126 	if (!iwpm_valid_client(nl_client))
127 		return ret;
128 	map_info = kzalloc(sizeof(struct iwpm_mapping_info), GFP_KERNEL);
129 	if (!map_info)
130 		return -ENOMEM;
131 
132 	memcpy(&map_info->local_sockaddr, local_sockaddr,
133 	       sizeof(struct sockaddr_storage));
134 	memcpy(&map_info->mapped_sockaddr, mapped_sockaddr,
135 	       sizeof(struct sockaddr_storage));
136 	map_info->nl_client = nl_client;
137 
138 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
139 	if (iwpm_hash_bucket) {
140 		hash_bucket_head = get_mapinfo_hash_bucket(
141 					&map_info->local_sockaddr,
142 					&map_info->mapped_sockaddr);
143 		if (hash_bucket_head) {
144 			hlist_add_head(&map_info->hlist_node, hash_bucket_head);
145 			ret = 0;
146 		}
147 	}
148 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
149 	return ret;
150 }
151 EXPORT_SYMBOL(iwpm_create_mapinfo);
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 EXPORT_SYMBOL(iwpm_remove_mapinfo);
188 
189 static void free_hash_bucket(void)
190 {
191 	struct hlist_node *tmp_hlist_node;
192 	struct iwpm_mapping_info *map_info;
193 	unsigned long flags;
194 	int i;
195 
196 	/* remove all the mapinfo data from the list */
197 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
198 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
199 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
200 			&iwpm_hash_bucket[i], hlist_node) {
201 
202 				hlist_del_init(&map_info->hlist_node);
203 				kfree(map_info);
204 			}
205 	}
206 	/* free the hash list */
207 	kfree(iwpm_hash_bucket);
208 	iwpm_hash_bucket = NULL;
209 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
210 }
211 
212 static void free_reminfo_bucket(void)
213 {
214 	struct hlist_node *tmp_hlist_node;
215 	struct iwpm_remote_info *rem_info;
216 	unsigned long flags;
217 	int i;
218 
219 	/* remove all the remote info from the list */
220 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
221 	for (i = 0; i < IWPM_REMINFO_HASH_SIZE; i++) {
222 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
223 			&iwpm_reminfo_bucket[i], hlist_node) {
224 
225 				hlist_del_init(&rem_info->hlist_node);
226 				kfree(rem_info);
227 			}
228 	}
229 	/* free the hash list */
230 	kfree(iwpm_reminfo_bucket);
231 	iwpm_reminfo_bucket = NULL;
232 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
233 }
234 
235 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage *,
236 						struct sockaddr_storage *);
237 
238 void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
239 {
240 	struct hlist_head *hash_bucket_head;
241 	unsigned long flags;
242 
243 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
244 	if (iwpm_reminfo_bucket) {
245 		hash_bucket_head = get_reminfo_hash_bucket(
246 					&rem_info->mapped_loc_sockaddr,
247 					&rem_info->mapped_rem_sockaddr);
248 		if (hash_bucket_head)
249 			hlist_add_head(&rem_info->hlist_node, hash_bucket_head);
250 	}
251 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
252 }
253 
254 int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
255 			 struct sockaddr_storage *mapped_rem_addr,
256 			 struct sockaddr_storage *remote_addr,
257 			 u8 nl_client)
258 {
259 	struct hlist_node *tmp_hlist_node;
260 	struct hlist_head *hash_bucket_head;
261 	struct iwpm_remote_info *rem_info = NULL;
262 	unsigned long flags;
263 	int ret = -EINVAL;
264 
265 	if (!iwpm_valid_client(nl_client)) {
266 		pr_info("%s: Invalid client = %d\n", __func__, nl_client);
267 		return ret;
268 	}
269 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
270 	if (iwpm_reminfo_bucket) {
271 		hash_bucket_head = get_reminfo_hash_bucket(
272 					mapped_loc_addr,
273 					mapped_rem_addr);
274 		if (!hash_bucket_head)
275 			goto get_remote_info_exit;
276 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
277 					hash_bucket_head, hlist_node) {
278 
279 			if (!iwpm_compare_sockaddr(&rem_info->mapped_loc_sockaddr,
280 				mapped_loc_addr) &&
281 				!iwpm_compare_sockaddr(&rem_info->mapped_rem_sockaddr,
282 				mapped_rem_addr)) {
283 
284 				memcpy(remote_addr, &rem_info->remote_sockaddr,
285 					sizeof(struct sockaddr_storage));
286 				iwpm_print_sockaddr(remote_addr,
287 						"get_remote_info: Remote sockaddr:");
288 
289 				hlist_del_init(&rem_info->hlist_node);
290 				kfree(rem_info);
291 				ret = 0;
292 				break;
293 			}
294 		}
295 	}
296 get_remote_info_exit:
297 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
298 	return ret;
299 }
300 EXPORT_SYMBOL(iwpm_get_remote_info);
301 
302 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
303 					u8 nl_client, gfp_t gfp)
304 {
305 	struct iwpm_nlmsg_request *nlmsg_request = NULL;
306 	unsigned long flags;
307 
308 	nlmsg_request = kzalloc(sizeof(struct iwpm_nlmsg_request), gfp);
309 	if (!nlmsg_request)
310 		return NULL;
311 
312 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
313 	list_add_tail(&nlmsg_request->inprocess_list, &iwpm_nlmsg_req_list);
314 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
315 
316 	kref_init(&nlmsg_request->kref);
317 	kref_get(&nlmsg_request->kref);
318 	nlmsg_request->nlmsg_seq = nlmsg_seq;
319 	nlmsg_request->nl_client = nl_client;
320 	nlmsg_request->request_done = 0;
321 	nlmsg_request->err_code = 0;
322 	sema_init(&nlmsg_request->sem, 1);
323 	down(&nlmsg_request->sem);
324 	return nlmsg_request;
325 }
326 
327 void iwpm_free_nlmsg_request(struct kref *kref)
328 {
329 	struct iwpm_nlmsg_request *nlmsg_request;
330 	unsigned long flags;
331 
332 	nlmsg_request = container_of(kref, struct iwpm_nlmsg_request, kref);
333 
334 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
335 	list_del_init(&nlmsg_request->inprocess_list);
336 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
337 
338 	if (!nlmsg_request->request_done)
339 		pr_debug("%s Freeing incomplete nlmsg request (seq = %u).\n",
340 			__func__, nlmsg_request->nlmsg_seq);
341 	kfree(nlmsg_request);
342 }
343 
344 struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
345 {
346 	struct iwpm_nlmsg_request *nlmsg_request;
347 	struct iwpm_nlmsg_request *found_request = NULL;
348 	unsigned long flags;
349 
350 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
351 	list_for_each_entry(nlmsg_request, &iwpm_nlmsg_req_list,
352 			    inprocess_list) {
353 		if (nlmsg_request->nlmsg_seq == echo_seq) {
354 			found_request = nlmsg_request;
355 			kref_get(&nlmsg_request->kref);
356 			break;
357 		}
358 	}
359 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
360 	return found_request;
361 }
362 
363 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
364 {
365 	int ret;
366 
367 	ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
368 	if (ret) {
369 		ret = -EINVAL;
370 		pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
371 			__func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
372 	} else {
373 		ret = nlmsg_request->err_code;
374 	}
375 	kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
376 	return ret;
377 }
378 
379 int iwpm_get_nlmsg_seq(void)
380 {
381 	return atomic_inc_return(&iwpm_admin.nlmsg_seq);
382 }
383 
384 int iwpm_valid_client(u8 nl_client)
385 {
386 	if (nl_client >= RDMA_NL_NUM_CLIENTS)
387 		return 0;
388 	return iwpm_admin.client_list[nl_client];
389 }
390 
391 void iwpm_set_valid(u8 nl_client, int valid)
392 {
393 	if (nl_client >= RDMA_NL_NUM_CLIENTS)
394 		return;
395 	iwpm_admin.client_list[nl_client] = valid;
396 }
397 
398 /* valid client */
399 u32 iwpm_get_registration(u8 nl_client)
400 {
401 	return iwpm_admin.reg_list[nl_client];
402 }
403 
404 /* valid client */
405 void iwpm_set_registration(u8 nl_client, u32 reg)
406 {
407 	iwpm_admin.reg_list[nl_client] = reg;
408 }
409 
410 /* valid client */
411 u32 iwpm_check_registration(u8 nl_client, u32 reg)
412 {
413 	return (iwpm_get_registration(nl_client) & reg);
414 }
415 
416 int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
417 				struct sockaddr_storage *b_sockaddr)
418 {
419 	if (a_sockaddr->ss_family != b_sockaddr->ss_family)
420 		return 1;
421 	if (a_sockaddr->ss_family == AF_INET) {
422 		struct sockaddr_in *a4_sockaddr =
423 			(struct sockaddr_in *)a_sockaddr;
424 		struct sockaddr_in *b4_sockaddr =
425 			(struct sockaddr_in *)b_sockaddr;
426 		if (!memcmp(&a4_sockaddr->sin_addr,
427 			&b4_sockaddr->sin_addr, sizeof(struct in_addr))
428 			&& a4_sockaddr->sin_port == b4_sockaddr->sin_port)
429 				return 0;
430 
431 	} else if (a_sockaddr->ss_family == AF_INET6) {
432 		struct sockaddr_in6 *a6_sockaddr =
433 			(struct sockaddr_in6 *)a_sockaddr;
434 		struct sockaddr_in6 *b6_sockaddr =
435 			(struct sockaddr_in6 *)b_sockaddr;
436 		if (!memcmp(&a6_sockaddr->sin6_addr,
437 			&b6_sockaddr->sin6_addr, sizeof(struct in6_addr))
438 			&& a6_sockaddr->sin6_port == b6_sockaddr->sin6_port)
439 				return 0;
440 
441 	} else {
442 		pr_err("%s: Invalid sockaddr family\n", __func__);
443 	}
444 	return 1;
445 }
446 
447 struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
448 						int nl_client)
449 {
450 	struct sk_buff *skb = NULL;
451 
452 	skb = dev_alloc_skb(IWPM_MSG_SIZE);
453 	if (!skb) {
454 		pr_err("%s Unable to allocate skb\n", __func__);
455 		goto create_nlmsg_exit;
456 	}
457 	if (!(ibnl_put_msg(skb, nlh, 0, 0, nl_client, nl_op,
458 			   NLM_F_REQUEST))) {
459 		pr_warn("%s: Unable to put the nlmsg header\n", __func__);
460 		dev_kfree_skb(skb);
461 		skb = NULL;
462 	}
463 create_nlmsg_exit:
464 	return skb;
465 }
466 
467 int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
468 				   const struct nla_policy *nlmsg_policy,
469 				   struct nlattr *nltb[], const char *msg_type)
470 {
471 	int nlh_len = 0;
472 	int ret;
473 	const char *err_str = "";
474 
475 	ret = nlmsg_validate(cb->nlh, nlh_len, policy_max - 1, nlmsg_policy,
476 			     NULL);
477 	if (ret) {
478 		err_str = "Invalid attribute";
479 		goto parse_nlmsg_error;
480 	}
481 	ret = nlmsg_parse(cb->nlh, nlh_len, nltb, policy_max - 1,
482 			  nlmsg_policy, NULL);
483 	if (ret) {
484 		err_str = "Unable to parse the nlmsg";
485 		goto parse_nlmsg_error;
486 	}
487 	ret = iwpm_validate_nlmsg_attr(nltb, policy_max);
488 	if (ret) {
489 		err_str = "Invalid NULL attribute";
490 		goto parse_nlmsg_error;
491 	}
492 	return 0;
493 parse_nlmsg_error:
494 	pr_warn("%s: %s (msg type %s ret = %d)\n",
495 			__func__, err_str, msg_type, ret);
496 	return ret;
497 }
498 
499 void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg)
500 {
501 	struct sockaddr_in6 *sockaddr_v6;
502 	struct sockaddr_in *sockaddr_v4;
503 
504 	switch (sockaddr->ss_family) {
505 	case AF_INET:
506 		sockaddr_v4 = (struct sockaddr_in *)sockaddr;
507 		pr_debug("%s IPV4 %pI4: %u(0x%04X)\n",
508 			msg, &sockaddr_v4->sin_addr,
509 			ntohs(sockaddr_v4->sin_port),
510 			ntohs(sockaddr_v4->sin_port));
511 		break;
512 	case AF_INET6:
513 		sockaddr_v6 = (struct sockaddr_in6 *)sockaddr;
514 		pr_debug("%s IPV6 %pI6: %u(0x%04X)\n",
515 			msg, &sockaddr_v6->sin6_addr,
516 			ntohs(sockaddr_v6->sin6_port),
517 			ntohs(sockaddr_v6->sin6_port));
518 		break;
519 	default:
520 		break;
521 	}
522 }
523 
524 static u32 iwpm_ipv6_jhash(struct sockaddr_in6 *ipv6_sockaddr)
525 {
526 	u32 ipv6_hash = jhash(&ipv6_sockaddr->sin6_addr, sizeof(struct in6_addr), 0);
527 	u32 hash = jhash_2words(ipv6_hash, (__force u32) ipv6_sockaddr->sin6_port, 0);
528 	return hash;
529 }
530 
531 static u32 iwpm_ipv4_jhash(struct sockaddr_in *ipv4_sockaddr)
532 {
533 	u32 ipv4_hash = jhash(&ipv4_sockaddr->sin_addr, sizeof(struct in_addr), 0);
534 	u32 hash = jhash_2words(ipv4_hash, (__force u32) ipv4_sockaddr->sin_port, 0);
535 	return hash;
536 }
537 
538 static int get_hash_bucket(struct sockaddr_storage *a_sockaddr,
539 				struct sockaddr_storage *b_sockaddr, u32 *hash)
540 {
541 	u32 a_hash, b_hash;
542 
543 	if (a_sockaddr->ss_family == AF_INET) {
544 		a_hash = iwpm_ipv4_jhash((struct sockaddr_in *) a_sockaddr);
545 		b_hash = iwpm_ipv4_jhash((struct sockaddr_in *) b_sockaddr);
546 
547 	} else if (a_sockaddr->ss_family == AF_INET6) {
548 		a_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) a_sockaddr);
549 		b_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) b_sockaddr);
550 	} else {
551 		pr_err("%s: Invalid sockaddr family\n", __func__);
552 		return -EINVAL;
553 	}
554 
555 	if (a_hash == b_hash) /* if port mapper isn't available */
556 		*hash = a_hash;
557 	else
558 		*hash = jhash_2words(a_hash, b_hash, 0);
559 	return 0;
560 }
561 
562 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage
563 				*local_sockaddr, struct sockaddr_storage
564 				*mapped_sockaddr)
565 {
566 	u32 hash;
567 	int ret;
568 
569 	ret = get_hash_bucket(local_sockaddr, mapped_sockaddr, &hash);
570 	if (ret)
571 		return NULL;
572 	return &iwpm_hash_bucket[hash & IWPM_MAPINFO_HASH_MASK];
573 }
574 
575 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage
576 				*mapped_loc_sockaddr, struct sockaddr_storage
577 				*mapped_rem_sockaddr)
578 {
579 	u32 hash;
580 	int ret;
581 
582 	ret = get_hash_bucket(mapped_loc_sockaddr, mapped_rem_sockaddr, &hash);
583 	if (ret)
584 		return NULL;
585 	return &iwpm_reminfo_bucket[hash & IWPM_REMINFO_HASH_MASK];
586 }
587 
588 static int send_mapinfo_num(u32 mapping_num, u8 nl_client, int iwpm_pid)
589 {
590 	struct sk_buff *skb = NULL;
591 	struct nlmsghdr *nlh;
592 	u32 msg_seq;
593 	const char *err_str = "";
594 	int ret = -EINVAL;
595 
596 	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_MAPINFO_NUM, &nlh, nl_client);
597 	if (!skb) {
598 		err_str = "Unable to create a nlmsg";
599 		goto mapinfo_num_error;
600 	}
601 	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
602 	msg_seq = 0;
603 	err_str = "Unable to put attribute of mapinfo number nlmsg";
604 	ret = ibnl_put_attr(skb, nlh, sizeof(u32), &msg_seq, IWPM_NLA_MAPINFO_SEQ);
605 	if (ret)
606 		goto mapinfo_num_error;
607 	ret = ibnl_put_attr(skb, nlh, sizeof(u32),
608 				&mapping_num, IWPM_NLA_MAPINFO_SEND_NUM);
609 	if (ret)
610 		goto mapinfo_num_error;
611 	ret = ibnl_unicast(skb, nlh, iwpm_pid);
612 	if (ret) {
613 		skb = NULL;
614 		err_str = "Unable to send a nlmsg";
615 		goto mapinfo_num_error;
616 	}
617 	pr_debug("%s: Sent mapping number = %d\n", __func__, mapping_num);
618 	return 0;
619 mapinfo_num_error:
620 	pr_info("%s: %s\n", __func__, err_str);
621 	if (skb)
622 		dev_kfree_skb(skb);
623 	return ret;
624 }
625 
626 static int send_nlmsg_done(struct sk_buff *skb, u8 nl_client, int iwpm_pid)
627 {
628 	struct nlmsghdr *nlh = NULL;
629 	int ret = 0;
630 
631 	if (!skb)
632 		return ret;
633 	if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
634 			   RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
635 		pr_warn("%s Unable to put NLMSG_DONE\n", __func__);
636 		dev_kfree_skb(skb);
637 		return -ENOMEM;
638 	}
639 	nlh->nlmsg_type = NLMSG_DONE;
640 	ret = ibnl_unicast(skb, (struct nlmsghdr *)skb->data, iwpm_pid);
641 	if (ret)
642 		pr_warn("%s Unable to send a nlmsg\n", __func__);
643 	return ret;
644 }
645 
646 int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid)
647 {
648 	struct iwpm_mapping_info *map_info;
649 	struct sk_buff *skb = NULL;
650 	struct nlmsghdr *nlh;
651 	int skb_num = 0, mapping_num = 0;
652 	int i = 0, nlmsg_bytes = 0;
653 	unsigned long flags;
654 	const char *err_str = "";
655 	int ret;
656 
657 	skb = dev_alloc_skb(NLMSG_GOODSIZE);
658 	if (!skb) {
659 		ret = -ENOMEM;
660 		err_str = "Unable to allocate skb";
661 		goto send_mapping_info_exit;
662 	}
663 	skb_num++;
664 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
665 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
666 		hlist_for_each_entry(map_info, &iwpm_hash_bucket[i],
667 				     hlist_node) {
668 			if (map_info->nl_client != nl_client)
669 				continue;
670 			nlh = NULL;
671 			if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
672 					RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
673 				ret = -ENOMEM;
674 				err_str = "Unable to put the nlmsg header";
675 				goto send_mapping_info_unlock;
676 			}
677 			err_str = "Unable to put attribute of the nlmsg";
678 			ret = ibnl_put_attr(skb, nlh,
679 					sizeof(struct sockaddr_storage),
680 					&map_info->local_sockaddr,
681 					IWPM_NLA_MAPINFO_LOCAL_ADDR);
682 			if (ret)
683 				goto send_mapping_info_unlock;
684 
685 			ret = ibnl_put_attr(skb, nlh,
686 					sizeof(struct sockaddr_storage),
687 					&map_info->mapped_sockaddr,
688 					IWPM_NLA_MAPINFO_MAPPED_ADDR);
689 			if (ret)
690 				goto send_mapping_info_unlock;
691 
692 			iwpm_print_sockaddr(&map_info->local_sockaddr,
693 				"send_mapping_info: Local sockaddr:");
694 			iwpm_print_sockaddr(&map_info->mapped_sockaddr,
695 				"send_mapping_info: Mapped local sockaddr:");
696 			mapping_num++;
697 			nlmsg_bytes += nlh->nlmsg_len;
698 
699 			/* check if all mappings can fit in one skb */
700 			if (NLMSG_GOODSIZE - nlmsg_bytes < nlh->nlmsg_len * 2) {
701 				/* and leave room for NLMSG_DONE */
702 				nlmsg_bytes = 0;
703 				skb_num++;
704 				spin_unlock_irqrestore(&iwpm_mapinfo_lock,
705 						       flags);
706 				/* send the skb */
707 				ret = send_nlmsg_done(skb, nl_client, iwpm_pid);
708 				skb = NULL;
709 				if (ret) {
710 					err_str = "Unable to send map info";
711 					goto send_mapping_info_exit;
712 				}
713 				if (skb_num == IWPM_MAPINFO_SKB_COUNT) {
714 					ret = -ENOMEM;
715 					err_str = "Insufficient skbs for map info";
716 					goto send_mapping_info_exit;
717 				}
718 				skb = dev_alloc_skb(NLMSG_GOODSIZE);
719 				if (!skb) {
720 					ret = -ENOMEM;
721 					err_str = "Unable to allocate skb";
722 					goto send_mapping_info_exit;
723 				}
724 				spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
725 			}
726 		}
727 	}
728 send_mapping_info_unlock:
729 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
730 send_mapping_info_exit:
731 	if (ret) {
732 		pr_warn("%s: %s (ret = %d)\n", __func__, err_str, ret);
733 		if (skb)
734 			dev_kfree_skb(skb);
735 		return ret;
736 	}
737 	send_nlmsg_done(skb, nl_client, iwpm_pid);
738 	return send_mapinfo_num(mapping_num, nl_client, iwpm_pid);
739 }
740 
741 int iwpm_mapinfo_available(void)
742 {
743 	unsigned long flags;
744 	int full_bucket = 0, i = 0;
745 
746 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
747 	if (iwpm_hash_bucket) {
748 		for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
749 			if (!hlist_empty(&iwpm_hash_bucket[i])) {
750 				full_bucket = 1;
751 				break;
752 			}
753 		}
754 	}
755 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
756 	return full_bucket;
757 }
758