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d353d8d4 MH |
1 | /* Copyright (C) 2012-2013 B.A.T.M.A.N. contributors: |
2 | * | |
3 | * Martin Hundebøll, Jeppe Ledet-Pedersen | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of version 2 of the GNU General Public | |
7 | * License as published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, but | |
10 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
12 | * General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA | |
17 | * 02110-1301, USA | |
18 | */ | |
19 | ||
d56b1705 MH |
20 | #include <linux/debugfs.h> |
21 | ||
d353d8d4 | 22 | #include "main.h" |
95332477 | 23 | #include "hash.h" |
d353d8d4 | 24 | #include "network-coding.h" |
95332477 | 25 | #include "send.h" |
d56b1705 MH |
26 | #include "originator.h" |
27 | #include "hard-interface.h" | |
d353d8d4 | 28 | |
95332477 MH |
29 | static struct lock_class_key batadv_nc_coding_hash_lock_class_key; |
30 | ||
d353d8d4 MH |
31 | static void batadv_nc_worker(struct work_struct *work); |
32 | ||
33 | /** | |
34 | * batadv_nc_start_timer - initialise the nc periodic worker | |
35 | * @bat_priv: the bat priv with all the soft interface information | |
36 | */ | |
37 | static void batadv_nc_start_timer(struct batadv_priv *bat_priv) | |
38 | { | |
39 | queue_delayed_work(batadv_event_workqueue, &bat_priv->nc.work, | |
40 | msecs_to_jiffies(10)); | |
41 | } | |
42 | ||
43 | /** | |
44 | * batadv_nc_init - initialise coding hash table and start house keeping | |
45 | * @bat_priv: the bat priv with all the soft interface information | |
46 | */ | |
47 | int batadv_nc_init(struct batadv_priv *bat_priv) | |
48 | { | |
95332477 MH |
49 | bat_priv->nc.timestamp_fwd_flush = jiffies; |
50 | ||
51 | if (bat_priv->nc.coding_hash) | |
52 | return 0; | |
53 | ||
54 | bat_priv->nc.coding_hash = batadv_hash_new(128); | |
55 | if (!bat_priv->nc.coding_hash) | |
56 | goto err; | |
57 | ||
58 | batadv_hash_set_lock_class(bat_priv->nc.coding_hash, | |
59 | &batadv_nc_coding_hash_lock_class_key); | |
60 | ||
d353d8d4 MH |
61 | INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker); |
62 | batadv_nc_start_timer(bat_priv); | |
63 | ||
64 | return 0; | |
95332477 MH |
65 | |
66 | err: | |
67 | return -ENOMEM; | |
d353d8d4 MH |
68 | } |
69 | ||
70 | /** | |
71 | * batadv_nc_init_bat_priv - initialise the nc specific bat_priv variables | |
72 | * @bat_priv: the bat priv with all the soft interface information | |
73 | */ | |
74 | void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv) | |
75 | { | |
76 | atomic_set(&bat_priv->network_coding, 1); | |
d56b1705 | 77 | bat_priv->nc.min_tq = 200; |
95332477 | 78 | bat_priv->nc.max_fwd_delay = 10; |
d56b1705 MH |
79 | } |
80 | ||
81 | /** | |
82 | * batadv_nc_init_orig - initialise the nc fields of an orig_node | |
83 | * @orig_node: the orig_node which is going to be initialised | |
84 | */ | |
85 | void batadv_nc_init_orig(struct batadv_orig_node *orig_node) | |
86 | { | |
87 | INIT_LIST_HEAD(&orig_node->in_coding_list); | |
88 | INIT_LIST_HEAD(&orig_node->out_coding_list); | |
89 | spin_lock_init(&orig_node->in_coding_list_lock); | |
90 | spin_lock_init(&orig_node->out_coding_list_lock); | |
91 | } | |
92 | ||
93 | /** | |
94 | * batadv_nc_node_free_rcu - rcu callback to free an nc node and remove | |
95 | * its refcount on the orig_node | |
96 | * @rcu: rcu pointer of the nc node | |
97 | */ | |
98 | static void batadv_nc_node_free_rcu(struct rcu_head *rcu) | |
99 | { | |
100 | struct batadv_nc_node *nc_node; | |
101 | ||
102 | nc_node = container_of(rcu, struct batadv_nc_node, rcu); | |
103 | batadv_orig_node_free_ref(nc_node->orig_node); | |
104 | kfree(nc_node); | |
105 | } | |
106 | ||
107 | /** | |
108 | * batadv_nc_node_free_ref - decrements the nc node refcounter and possibly | |
109 | * frees it | |
110 | * @nc_node: the nc node to free | |
111 | */ | |
112 | static void batadv_nc_node_free_ref(struct batadv_nc_node *nc_node) | |
113 | { | |
114 | if (atomic_dec_and_test(&nc_node->refcount)) | |
115 | call_rcu(&nc_node->rcu, batadv_nc_node_free_rcu); | |
116 | } | |
117 | ||
95332477 MH |
118 | /** |
119 | * batadv_nc_path_free_ref - decrements the nc path refcounter and possibly | |
120 | * frees it | |
121 | * @nc_path: the nc node to free | |
122 | */ | |
123 | static void batadv_nc_path_free_ref(struct batadv_nc_path *nc_path) | |
124 | { | |
125 | if (atomic_dec_and_test(&nc_path->refcount)) | |
126 | kfree_rcu(nc_path, rcu); | |
127 | } | |
128 | ||
129 | /** | |
130 | * batadv_nc_packet_free - frees nc packet | |
131 | * @nc_packet: the nc packet to free | |
132 | */ | |
133 | static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet) | |
134 | { | |
135 | if (nc_packet->skb) | |
136 | kfree_skb(nc_packet->skb); | |
137 | ||
138 | batadv_nc_path_free_ref(nc_packet->nc_path); | |
139 | kfree(nc_packet); | |
140 | } | |
141 | ||
d56b1705 MH |
142 | /** |
143 | * batadv_nc_to_purge_nc_node - checks whether an nc node has to be purged | |
144 | * @bat_priv: the bat priv with all the soft interface information | |
145 | * @nc_node: the nc node to check | |
146 | * | |
147 | * Returns true if the entry has to be purged now, false otherwise | |
148 | */ | |
149 | static bool batadv_nc_to_purge_nc_node(struct batadv_priv *bat_priv, | |
150 | struct batadv_nc_node *nc_node) | |
151 | { | |
152 | if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE) | |
153 | return true; | |
154 | ||
155 | return batadv_has_timed_out(nc_node->last_seen, BATADV_NC_NODE_TIMEOUT); | |
156 | } | |
157 | ||
95332477 MH |
158 | /** |
159 | * batadv_nc_to_purge_nc_path_coding - checks whether an nc path has timed out | |
160 | * @bat_priv: the bat priv with all the soft interface information | |
161 | * @nc_path: the nc path to check | |
162 | * | |
163 | * Returns true if the entry has to be purged now, false otherwise | |
164 | */ | |
165 | static bool batadv_nc_to_purge_nc_path_coding(struct batadv_priv *bat_priv, | |
166 | struct batadv_nc_path *nc_path) | |
167 | { | |
168 | if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE) | |
169 | return true; | |
170 | ||
171 | /* purge the path when no packets has been added for 10 times the | |
172 | * max_fwd_delay time | |
173 | */ | |
174 | return batadv_has_timed_out(nc_path->last_valid, | |
175 | bat_priv->nc.max_fwd_delay * 10); | |
176 | } | |
177 | ||
d56b1705 MH |
178 | /** |
179 | * batadv_nc_purge_orig_nc_nodes - go through list of nc nodes and purge stale | |
180 | * entries | |
181 | * @bat_priv: the bat priv with all the soft interface information | |
182 | * @list: list of nc nodes | |
183 | * @lock: nc node list lock | |
184 | * @to_purge: function in charge to decide whether an entry has to be purged or | |
185 | * not. This function takes the nc node as argument and has to return | |
186 | * a boolean value: true if the entry has to be deleted, false | |
187 | * otherwise | |
188 | */ | |
189 | static void | |
190 | batadv_nc_purge_orig_nc_nodes(struct batadv_priv *bat_priv, | |
191 | struct list_head *list, | |
192 | spinlock_t *lock, | |
193 | bool (*to_purge)(struct batadv_priv *, | |
194 | struct batadv_nc_node *)) | |
195 | { | |
196 | struct batadv_nc_node *nc_node, *nc_node_tmp; | |
197 | ||
198 | /* For each nc_node in list */ | |
199 | spin_lock_bh(lock); | |
200 | list_for_each_entry_safe(nc_node, nc_node_tmp, list, list) { | |
201 | /* if an helper function has been passed as parameter, | |
202 | * ask it if the entry has to be purged or not | |
203 | */ | |
204 | if (to_purge && !to_purge(bat_priv, nc_node)) | |
205 | continue; | |
206 | ||
207 | batadv_dbg(BATADV_DBG_NC, bat_priv, | |
208 | "Removing nc_node %pM -> %pM\n", | |
209 | nc_node->addr, nc_node->orig_node->orig); | |
210 | list_del_rcu(&nc_node->list); | |
211 | batadv_nc_node_free_ref(nc_node); | |
212 | } | |
213 | spin_unlock_bh(lock); | |
214 | } | |
215 | ||
216 | /** | |
217 | * batadv_nc_purge_orig - purges all nc node data attached of the given | |
218 | * originator | |
219 | * @bat_priv: the bat priv with all the soft interface information | |
220 | * @orig_node: orig_node with the nc node entries to be purged | |
221 | * @to_purge: function in charge to decide whether an entry has to be purged or | |
222 | * not. This function takes the nc node as argument and has to return | |
223 | * a boolean value: true is the entry has to be deleted, false | |
224 | * otherwise | |
225 | */ | |
226 | void batadv_nc_purge_orig(struct batadv_priv *bat_priv, | |
227 | struct batadv_orig_node *orig_node, | |
228 | bool (*to_purge)(struct batadv_priv *, | |
229 | struct batadv_nc_node *)) | |
230 | { | |
231 | /* Check ingoing nc_node's of this orig_node */ | |
232 | batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->in_coding_list, | |
233 | &orig_node->in_coding_list_lock, | |
234 | to_purge); | |
235 | ||
236 | /* Check outgoing nc_node's of this orig_node */ | |
237 | batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->out_coding_list, | |
238 | &orig_node->out_coding_list_lock, | |
239 | to_purge); | |
240 | } | |
241 | ||
242 | /** | |
243 | * batadv_nc_purge_orig_hash - traverse entire originator hash to check if they | |
244 | * have timed out nc nodes | |
245 | * @bat_priv: the bat priv with all the soft interface information | |
246 | */ | |
247 | static void batadv_nc_purge_orig_hash(struct batadv_priv *bat_priv) | |
248 | { | |
249 | struct batadv_hashtable *hash = bat_priv->orig_hash; | |
250 | struct hlist_head *head; | |
251 | struct batadv_orig_node *orig_node; | |
252 | uint32_t i; | |
253 | ||
254 | if (!hash) | |
255 | return; | |
256 | ||
257 | /* For each orig_node */ | |
258 | for (i = 0; i < hash->size; i++) { | |
259 | head = &hash->table[i]; | |
260 | ||
261 | rcu_read_lock(); | |
262 | hlist_for_each_entry_rcu(orig_node, head, hash_entry) | |
263 | batadv_nc_purge_orig(bat_priv, orig_node, | |
264 | batadv_nc_to_purge_nc_node); | |
265 | rcu_read_unlock(); | |
266 | } | |
d353d8d4 MH |
267 | } |
268 | ||
95332477 MH |
269 | /** |
270 | * batadv_nc_purge_paths - traverse all nc paths part of the hash and remove | |
271 | * unused ones | |
272 | * @bat_priv: the bat priv with all the soft interface information | |
273 | * @hash: hash table containing the nc paths to check | |
274 | * @to_purge: function in charge to decide whether an entry has to be purged or | |
275 | * not. This function takes the nc node as argument and has to return | |
276 | * a boolean value: true is the entry has to be deleted, false | |
277 | * otherwise | |
278 | */ | |
279 | static void batadv_nc_purge_paths(struct batadv_priv *bat_priv, | |
280 | struct batadv_hashtable *hash, | |
281 | bool (*to_purge)(struct batadv_priv *, | |
282 | struct batadv_nc_path *)) | |
283 | { | |
284 | struct hlist_head *head; | |
285 | struct hlist_node *node_tmp; | |
286 | struct batadv_nc_path *nc_path; | |
287 | spinlock_t *lock; /* Protects lists in hash */ | |
288 | uint32_t i; | |
289 | ||
290 | for (i = 0; i < hash->size; i++) { | |
291 | head = &hash->table[i]; | |
292 | lock = &hash->list_locks[i]; | |
293 | ||
294 | /* For each nc_path in this bin */ | |
295 | spin_lock_bh(lock); | |
296 | hlist_for_each_entry_safe(nc_path, node_tmp, head, hash_entry) { | |
297 | /* if an helper function has been passed as parameter, | |
298 | * ask it if the entry has to be purged or not | |
299 | */ | |
300 | if (to_purge && !to_purge(bat_priv, nc_path)) | |
301 | continue; | |
302 | ||
303 | /* purging an non-empty nc_path should never happen, but | |
304 | * is observed under high CPU load. Delay the purging | |
305 | * until next iteration to allow the packet_list to be | |
306 | * emptied first. | |
307 | */ | |
308 | if (!unlikely(list_empty(&nc_path->packet_list))) { | |
309 | net_ratelimited_function(printk, | |
310 | KERN_WARNING | |
311 | "Skipping free of non-empty nc_path (%pM -> %pM)!\n", | |
312 | nc_path->prev_hop, | |
313 | nc_path->next_hop); | |
314 | continue; | |
315 | } | |
316 | ||
317 | /* nc_path is unused, so remove it */ | |
318 | batadv_dbg(BATADV_DBG_NC, bat_priv, | |
319 | "Remove nc_path %pM -> %pM\n", | |
320 | nc_path->prev_hop, nc_path->next_hop); | |
321 | hlist_del_rcu(&nc_path->hash_entry); | |
322 | batadv_nc_path_free_ref(nc_path); | |
323 | } | |
324 | spin_unlock_bh(lock); | |
325 | } | |
326 | } | |
327 | ||
328 | /** | |
329 | * batadv_nc_hash_key_gen - computes the nc_path hash key | |
330 | * @key: buffer to hold the final hash key | |
331 | * @src: source ethernet mac address going into the hash key | |
332 | * @dst: destination ethernet mac address going into the hash key | |
333 | */ | |
334 | static void batadv_nc_hash_key_gen(struct batadv_nc_path *key, const char *src, | |
335 | const char *dst) | |
336 | { | |
337 | memcpy(key->prev_hop, src, sizeof(key->prev_hop)); | |
338 | memcpy(key->next_hop, dst, sizeof(key->next_hop)); | |
339 | } | |
340 | ||
341 | /** | |
342 | * batadv_nc_hash_choose - compute the hash value for an nc path | |
343 | * @data: data to hash | |
344 | * @size: size of the hash table | |
345 | * | |
346 | * Returns the selected index in the hash table for the given data. | |
347 | */ | |
348 | static uint32_t batadv_nc_hash_choose(const void *data, uint32_t size) | |
349 | { | |
350 | const struct batadv_nc_path *nc_path = data; | |
351 | uint32_t hash = 0; | |
352 | ||
353 | hash = batadv_hash_bytes(hash, &nc_path->prev_hop, | |
354 | sizeof(nc_path->prev_hop)); | |
355 | hash = batadv_hash_bytes(hash, &nc_path->next_hop, | |
356 | sizeof(nc_path->next_hop)); | |
357 | ||
358 | hash += (hash << 3); | |
359 | hash ^= (hash >> 11); | |
360 | hash += (hash << 15); | |
361 | ||
362 | return hash % size; | |
363 | } | |
364 | ||
365 | /** | |
366 | * batadv_nc_hash_compare - comparing function used in the network coding hash | |
367 | * tables | |
368 | * @node: node in the local table | |
369 | * @data2: second object to compare the node to | |
370 | * | |
371 | * Returns 1 if the two entry are the same, 0 otherwise | |
372 | */ | |
373 | static int batadv_nc_hash_compare(const struct hlist_node *node, | |
374 | const void *data2) | |
375 | { | |
376 | const struct batadv_nc_path *nc_path1, *nc_path2; | |
377 | ||
378 | nc_path1 = container_of(node, struct batadv_nc_path, hash_entry); | |
379 | nc_path2 = data2; | |
380 | ||
381 | /* Return 1 if the two keys are identical */ | |
382 | if (memcmp(nc_path1->prev_hop, nc_path2->prev_hop, | |
383 | sizeof(nc_path1->prev_hop)) != 0) | |
384 | return 0; | |
385 | ||
386 | if (memcmp(nc_path1->next_hop, nc_path2->next_hop, | |
387 | sizeof(nc_path1->next_hop)) != 0) | |
388 | return 0; | |
389 | ||
390 | return 1; | |
391 | } | |
392 | ||
393 | /** | |
394 | * batadv_nc_hash_find - search for an existing nc path and return it | |
395 | * @hash: hash table containing the nc path | |
396 | * @data: search key | |
397 | * | |
398 | * Returns the nc_path if found, NULL otherwise. | |
399 | */ | |
400 | static struct batadv_nc_path * | |
401 | batadv_nc_hash_find(struct batadv_hashtable *hash, | |
402 | void *data) | |
403 | { | |
404 | struct hlist_head *head; | |
405 | struct batadv_nc_path *nc_path, *nc_path_tmp = NULL; | |
406 | int index; | |
407 | ||
408 | if (!hash) | |
409 | return NULL; | |
410 | ||
411 | index = batadv_nc_hash_choose(data, hash->size); | |
412 | head = &hash->table[index]; | |
413 | ||
414 | rcu_read_lock(); | |
415 | hlist_for_each_entry_rcu(nc_path, head, hash_entry) { | |
416 | if (!batadv_nc_hash_compare(&nc_path->hash_entry, data)) | |
417 | continue; | |
418 | ||
419 | if (!atomic_inc_not_zero(&nc_path->refcount)) | |
420 | continue; | |
421 | ||
422 | nc_path_tmp = nc_path; | |
423 | break; | |
424 | } | |
425 | rcu_read_unlock(); | |
426 | ||
427 | return nc_path_tmp; | |
428 | } | |
429 | ||
430 | /** | |
431 | * batadv_nc_send_packet - send non-coded packet and free nc_packet struct | |
432 | * @nc_packet: the nc packet to send | |
433 | */ | |
434 | static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet) | |
435 | { | |
436 | batadv_send_skb_packet(nc_packet->skb, | |
437 | nc_packet->neigh_node->if_incoming, | |
438 | nc_packet->nc_path->next_hop); | |
439 | nc_packet->skb = NULL; | |
440 | batadv_nc_packet_free(nc_packet); | |
441 | } | |
442 | ||
443 | /** | |
444 | * batadv_nc_fwd_flush - Checks the timestamp of the given nc packet. | |
445 | * @bat_priv: the bat priv with all the soft interface information | |
446 | * @nc_path: the nc path the packet belongs to | |
447 | * @nc_packet: the nc packet to be checked | |
448 | * | |
449 | * Checks whether the given nc packet has hit its forward timeout. If so, the | |
450 | * packet is no longer delayed, immediately sent and the entry deleted from the | |
451 | * queue. Has to be called with the appropriate locks. | |
452 | * | |
453 | * Returns false as soon as the entry in the fifo queue has not been timed out | |
454 | * yet and true otherwise. | |
455 | */ | |
456 | static bool batadv_nc_fwd_flush(struct batadv_priv *bat_priv, | |
457 | struct batadv_nc_path *nc_path, | |
458 | struct batadv_nc_packet *nc_packet) | |
459 | { | |
460 | unsigned long timeout = bat_priv->nc.max_fwd_delay; | |
461 | ||
462 | /* Packets are added to tail, so the remaining packets did not time | |
463 | * out and we can stop processing the current queue | |
464 | */ | |
465 | if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE && | |
466 | !batadv_has_timed_out(nc_packet->timestamp, timeout)) | |
467 | return false; | |
468 | ||
469 | /* Send packet */ | |
470 | batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD); | |
471 | batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES, | |
472 | nc_packet->skb->len + ETH_HLEN); | |
473 | list_del(&nc_packet->list); | |
474 | batadv_nc_send_packet(nc_packet); | |
475 | ||
476 | return true; | |
477 | } | |
478 | ||
479 | /** | |
480 | * batadv_nc_process_nc_paths - traverse given nc packet pool and free timed out | |
481 | * nc packets | |
482 | * @bat_priv: the bat priv with all the soft interface information | |
483 | * @hash: to be processed hash table | |
484 | * @process_fn: Function called to process given nc packet. Should return true | |
485 | * to encourage this function to proceed with the next packet. | |
486 | * Otherwise the rest of the current queue is skipped. | |
487 | */ | |
488 | static void | |
489 | batadv_nc_process_nc_paths(struct batadv_priv *bat_priv, | |
490 | struct batadv_hashtable *hash, | |
491 | bool (*process_fn)(struct batadv_priv *, | |
492 | struct batadv_nc_path *, | |
493 | struct batadv_nc_packet *)) | |
494 | { | |
495 | struct hlist_head *head; | |
496 | struct batadv_nc_packet *nc_packet, *nc_packet_tmp; | |
497 | struct batadv_nc_path *nc_path; | |
498 | bool ret; | |
499 | int i; | |
500 | ||
501 | if (!hash) | |
502 | return; | |
503 | ||
504 | /* Loop hash table bins */ | |
505 | for (i = 0; i < hash->size; i++) { | |
506 | head = &hash->table[i]; | |
507 | ||
508 | /* Loop coding paths */ | |
509 | rcu_read_lock(); | |
510 | hlist_for_each_entry_rcu(nc_path, head, hash_entry) { | |
511 | /* Loop packets */ | |
512 | spin_lock_bh(&nc_path->packet_list_lock); | |
513 | list_for_each_entry_safe(nc_packet, nc_packet_tmp, | |
514 | &nc_path->packet_list, list) { | |
515 | ret = process_fn(bat_priv, nc_path, nc_packet); | |
516 | if (!ret) | |
517 | break; | |
518 | } | |
519 | spin_unlock_bh(&nc_path->packet_list_lock); | |
520 | } | |
521 | rcu_read_unlock(); | |
522 | } | |
523 | } | |
524 | ||
d353d8d4 MH |
525 | /** |
526 | * batadv_nc_worker - periodic task for house keeping related to network coding | |
527 | * @work: kernel work struct | |
528 | */ | |
529 | static void batadv_nc_worker(struct work_struct *work) | |
530 | { | |
531 | struct delayed_work *delayed_work; | |
532 | struct batadv_priv_nc *priv_nc; | |
533 | struct batadv_priv *bat_priv; | |
95332477 | 534 | unsigned long timeout; |
d353d8d4 MH |
535 | |
536 | delayed_work = container_of(work, struct delayed_work, work); | |
537 | priv_nc = container_of(delayed_work, struct batadv_priv_nc, work); | |
538 | bat_priv = container_of(priv_nc, struct batadv_priv, nc); | |
539 | ||
d56b1705 | 540 | batadv_nc_purge_orig_hash(bat_priv); |
95332477 MH |
541 | batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash, |
542 | batadv_nc_to_purge_nc_path_coding); | |
543 | ||
544 | timeout = bat_priv->nc.max_fwd_delay; | |
545 | ||
546 | if (batadv_has_timed_out(bat_priv->nc.timestamp_fwd_flush, timeout)) { | |
547 | batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.coding_hash, | |
548 | batadv_nc_fwd_flush); | |
549 | bat_priv->nc.timestamp_fwd_flush = jiffies; | |
550 | } | |
d56b1705 | 551 | |
d353d8d4 MH |
552 | /* Schedule a new check */ |
553 | batadv_nc_start_timer(bat_priv); | |
554 | } | |
555 | ||
d56b1705 MH |
556 | /** |
557 | * batadv_can_nc_with_orig - checks whether the given orig node is suitable for | |
558 | * coding or not | |
559 | * @bat_priv: the bat priv with all the soft interface information | |
560 | * @orig_node: neighboring orig node which may be used as nc candidate | |
561 | * @ogm_packet: incoming ogm packet also used for the checks | |
562 | * | |
563 | * Returns true if: | |
564 | * 1) The OGM must have the most recent sequence number. | |
565 | * 2) The TTL must be decremented by one and only one. | |
566 | * 3) The OGM must be received from the first hop from orig_node. | |
567 | * 4) The TQ value of the OGM must be above bat_priv->nc.min_tq. | |
568 | */ | |
569 | static bool batadv_can_nc_with_orig(struct batadv_priv *bat_priv, | |
570 | struct batadv_orig_node *orig_node, | |
571 | struct batadv_ogm_packet *ogm_packet) | |
572 | { | |
573 | if (orig_node->last_real_seqno != ogm_packet->seqno) | |
574 | return false; | |
575 | if (orig_node->last_ttl != ogm_packet->header.ttl + 1) | |
576 | return false; | |
577 | if (!batadv_compare_eth(ogm_packet->orig, ogm_packet->prev_sender)) | |
578 | return false; | |
579 | if (ogm_packet->tq < bat_priv->nc.min_tq) | |
580 | return false; | |
581 | ||
582 | return true; | |
583 | } | |
584 | ||
585 | /** | |
586 | * batadv_nc_find_nc_node - search for an existing nc node and return it | |
587 | * @orig_node: orig node originating the ogm packet | |
588 | * @orig_neigh_node: neighboring orig node from which we received the ogm packet | |
589 | * (can be equal to orig_node) | |
590 | * @in_coding: traverse incoming or outgoing network coding list | |
591 | * | |
592 | * Returns the nc_node if found, NULL otherwise. | |
593 | */ | |
594 | static struct batadv_nc_node | |
595 | *batadv_nc_find_nc_node(struct batadv_orig_node *orig_node, | |
596 | struct batadv_orig_node *orig_neigh_node, | |
597 | bool in_coding) | |
598 | { | |
599 | struct batadv_nc_node *nc_node, *nc_node_out = NULL; | |
600 | struct list_head *list; | |
601 | ||
602 | if (in_coding) | |
603 | list = &orig_neigh_node->in_coding_list; | |
604 | else | |
605 | list = &orig_neigh_node->out_coding_list; | |
606 | ||
607 | /* Traverse list of nc_nodes to orig_node */ | |
608 | rcu_read_lock(); | |
609 | list_for_each_entry_rcu(nc_node, list, list) { | |
610 | if (!batadv_compare_eth(nc_node->addr, orig_node->orig)) | |
611 | continue; | |
612 | ||
613 | if (!atomic_inc_not_zero(&nc_node->refcount)) | |
614 | continue; | |
615 | ||
616 | /* Found a match */ | |
617 | nc_node_out = nc_node; | |
618 | break; | |
619 | } | |
620 | rcu_read_unlock(); | |
621 | ||
622 | return nc_node_out; | |
623 | } | |
624 | ||
625 | /** | |
626 | * batadv_nc_get_nc_node - retrieves an nc node or creates the entry if it was | |
627 | * not found | |
628 | * @bat_priv: the bat priv with all the soft interface information | |
629 | * @orig_node: orig node originating the ogm packet | |
630 | * @orig_neigh_node: neighboring orig node from which we received the ogm packet | |
631 | * (can be equal to orig_node) | |
632 | * @in_coding: traverse incoming or outgoing network coding list | |
633 | * | |
634 | * Returns the nc_node if found or created, NULL in case of an error. | |
635 | */ | |
636 | static struct batadv_nc_node | |
637 | *batadv_nc_get_nc_node(struct batadv_priv *bat_priv, | |
638 | struct batadv_orig_node *orig_node, | |
639 | struct batadv_orig_node *orig_neigh_node, | |
640 | bool in_coding) | |
641 | { | |
642 | struct batadv_nc_node *nc_node; | |
643 | spinlock_t *lock; /* Used to lock list selected by "int in_coding" */ | |
644 | struct list_head *list; | |
645 | ||
646 | /* Check if nc_node is already added */ | |
647 | nc_node = batadv_nc_find_nc_node(orig_node, orig_neigh_node, in_coding); | |
648 | ||
649 | /* Node found */ | |
650 | if (nc_node) | |
651 | return nc_node; | |
652 | ||
653 | nc_node = kzalloc(sizeof(*nc_node), GFP_ATOMIC); | |
654 | if (!nc_node) | |
655 | return NULL; | |
656 | ||
657 | if (!atomic_inc_not_zero(&orig_neigh_node->refcount)) | |
658 | goto free; | |
659 | ||
660 | /* Initialize nc_node */ | |
661 | INIT_LIST_HEAD(&nc_node->list); | |
662 | memcpy(nc_node->addr, orig_node->orig, ETH_ALEN); | |
663 | nc_node->orig_node = orig_neigh_node; | |
664 | atomic_set(&nc_node->refcount, 2); | |
665 | ||
666 | /* Select ingoing or outgoing coding node */ | |
667 | if (in_coding) { | |
668 | lock = &orig_neigh_node->in_coding_list_lock; | |
669 | list = &orig_neigh_node->in_coding_list; | |
670 | } else { | |
671 | lock = &orig_neigh_node->out_coding_list_lock; | |
672 | list = &orig_neigh_node->out_coding_list; | |
673 | } | |
674 | ||
675 | batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_node %pM -> %pM\n", | |
676 | nc_node->addr, nc_node->orig_node->orig); | |
677 | ||
678 | /* Add nc_node to orig_node */ | |
679 | spin_lock_bh(lock); | |
680 | list_add_tail_rcu(&nc_node->list, list); | |
681 | spin_unlock_bh(lock); | |
682 | ||
683 | return nc_node; | |
684 | ||
685 | free: | |
686 | kfree(nc_node); | |
687 | return NULL; | |
688 | } | |
689 | ||
690 | /** | |
691 | * batadv_nc_update_nc_node - updates stored incoming and outgoing nc node structs | |
692 | * (best called on incoming OGMs) | |
693 | * @bat_priv: the bat priv with all the soft interface information | |
694 | * @orig_node: orig node originating the ogm packet | |
695 | * @orig_neigh_node: neighboring orig node from which we received the ogm packet | |
696 | * (can be equal to orig_node) | |
697 | * @ogm_packet: incoming ogm packet | |
698 | * @is_single_hop_neigh: orig_node is a single hop neighbor | |
699 | */ | |
700 | void batadv_nc_update_nc_node(struct batadv_priv *bat_priv, | |
701 | struct batadv_orig_node *orig_node, | |
702 | struct batadv_orig_node *orig_neigh_node, | |
703 | struct batadv_ogm_packet *ogm_packet, | |
704 | int is_single_hop_neigh) | |
705 | { | |
706 | struct batadv_nc_node *in_nc_node = NULL, *out_nc_node = NULL; | |
707 | ||
708 | /* Check if network coding is enabled */ | |
709 | if (!atomic_read(&bat_priv->network_coding)) | |
710 | goto out; | |
711 | ||
712 | /* accept ogms from 'good' neighbors and single hop neighbors */ | |
713 | if (!batadv_can_nc_with_orig(bat_priv, orig_node, ogm_packet) && | |
714 | !is_single_hop_neigh) | |
715 | goto out; | |
716 | ||
717 | /* Add orig_node as in_nc_node on hop */ | |
718 | in_nc_node = batadv_nc_get_nc_node(bat_priv, orig_node, | |
719 | orig_neigh_node, true); | |
720 | if (!in_nc_node) | |
721 | goto out; | |
722 | ||
723 | in_nc_node->last_seen = jiffies; | |
724 | ||
725 | /* Add hop as out_nc_node on orig_node */ | |
726 | out_nc_node = batadv_nc_get_nc_node(bat_priv, orig_neigh_node, | |
727 | orig_node, false); | |
728 | if (!out_nc_node) | |
729 | goto out; | |
730 | ||
731 | out_nc_node->last_seen = jiffies; | |
732 | ||
733 | out: | |
734 | if (in_nc_node) | |
735 | batadv_nc_node_free_ref(in_nc_node); | |
736 | if (out_nc_node) | |
737 | batadv_nc_node_free_ref(out_nc_node); | |
738 | } | |
739 | ||
95332477 MH |
740 | /** |
741 | * batadv_nc_get_path - get existing nc_path or allocate a new one | |
742 | * @bat_priv: the bat priv with all the soft interface information | |
743 | * @hash: hash table containing the nc path | |
744 | * @src: ethernet source address - first half of the nc path search key | |
745 | * @dst: ethernet destination address - second half of the nc path search key | |
746 | * | |
747 | * Returns pointer to nc_path if the path was found or created, returns NULL | |
748 | * on error. | |
749 | */ | |
750 | static struct batadv_nc_path *batadv_nc_get_path(struct batadv_priv *bat_priv, | |
751 | struct batadv_hashtable *hash, | |
752 | uint8_t *src, | |
753 | uint8_t *dst) | |
754 | { | |
755 | int hash_added; | |
756 | struct batadv_nc_path *nc_path, nc_path_key; | |
757 | ||
758 | batadv_nc_hash_key_gen(&nc_path_key, src, dst); | |
759 | ||
760 | /* Search for existing nc_path */ | |
761 | nc_path = batadv_nc_hash_find(hash, (void *)&nc_path_key); | |
762 | ||
763 | if (nc_path) { | |
764 | /* Set timestamp to delay removal of nc_path */ | |
765 | nc_path->last_valid = jiffies; | |
766 | return nc_path; | |
767 | } | |
768 | ||
769 | /* No existing nc_path was found; create a new */ | |
770 | nc_path = kzalloc(sizeof(*nc_path), GFP_ATOMIC); | |
771 | ||
772 | if (!nc_path) | |
773 | return NULL; | |
774 | ||
775 | /* Initialize nc_path */ | |
776 | INIT_LIST_HEAD(&nc_path->packet_list); | |
777 | spin_lock_init(&nc_path->packet_list_lock); | |
778 | atomic_set(&nc_path->refcount, 2); | |
779 | nc_path->last_valid = jiffies; | |
780 | memcpy(nc_path->next_hop, dst, ETH_ALEN); | |
781 | memcpy(nc_path->prev_hop, src, ETH_ALEN); | |
782 | ||
783 | batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_path %pM -> %pM\n", | |
784 | nc_path->prev_hop, | |
785 | nc_path->next_hop); | |
786 | ||
787 | /* Add nc_path to hash table */ | |
788 | hash_added = batadv_hash_add(hash, batadv_nc_hash_compare, | |
789 | batadv_nc_hash_choose, &nc_path_key, | |
790 | &nc_path->hash_entry); | |
791 | ||
792 | if (hash_added < 0) { | |
793 | kfree(nc_path); | |
794 | return NULL; | |
795 | } | |
796 | ||
797 | return nc_path; | |
798 | } | |
799 | ||
800 | /** | |
801 | * batadv_nc_skb_add_to_path - buffer skb for later encoding / decoding | |
802 | * @skb: skb to add to path | |
803 | * @nc_path: path to add skb to | |
804 | * @neigh_node: next hop to forward packet to | |
805 | * @packet_id: checksum to identify packet | |
806 | * | |
807 | * Returns true if the packet was buffered or false in case of an error. | |
808 | */ | |
809 | static bool batadv_nc_skb_add_to_path(struct sk_buff *skb, | |
810 | struct batadv_nc_path *nc_path, | |
811 | struct batadv_neigh_node *neigh_node, | |
812 | __be32 packet_id) | |
813 | { | |
814 | struct batadv_nc_packet *nc_packet; | |
815 | ||
816 | nc_packet = kzalloc(sizeof(*nc_packet), GFP_ATOMIC); | |
817 | if (!nc_packet) | |
818 | return false; | |
819 | ||
820 | /* Initialize nc_packet */ | |
821 | nc_packet->timestamp = jiffies; | |
822 | nc_packet->packet_id = packet_id; | |
823 | nc_packet->skb = skb; | |
824 | nc_packet->neigh_node = neigh_node; | |
825 | nc_packet->nc_path = nc_path; | |
826 | ||
827 | /* Add coding packet to list */ | |
828 | spin_lock_bh(&nc_path->packet_list_lock); | |
829 | list_add_tail(&nc_packet->list, &nc_path->packet_list); | |
830 | spin_unlock_bh(&nc_path->packet_list_lock); | |
831 | ||
832 | return true; | |
833 | } | |
834 | ||
835 | /** | |
836 | * batadv_nc_skb_forward - try to code a packet or add it to the coding packet | |
837 | * buffer | |
838 | * @skb: data skb to forward | |
839 | * @neigh_node: next hop to forward packet to | |
840 | * @ethhdr: pointer to the ethernet header inside the skb | |
841 | * | |
842 | * Returns true if the skb was consumed (encoded packet sent) or false otherwise | |
843 | */ | |
844 | bool batadv_nc_skb_forward(struct sk_buff *skb, | |
845 | struct batadv_neigh_node *neigh_node, | |
846 | struct ethhdr *ethhdr) | |
847 | { | |
848 | const struct net_device *netdev = neigh_node->if_incoming->soft_iface; | |
849 | struct batadv_priv *bat_priv = netdev_priv(netdev); | |
850 | struct batadv_unicast_packet *packet; | |
851 | struct batadv_nc_path *nc_path; | |
852 | __be32 packet_id; | |
853 | u8 *payload; | |
854 | ||
855 | /* Check if network coding is enabled */ | |
856 | if (!atomic_read(&bat_priv->network_coding)) | |
857 | goto out; | |
858 | ||
859 | /* We only handle unicast packets */ | |
860 | payload = skb_network_header(skb); | |
861 | packet = (struct batadv_unicast_packet *)payload; | |
862 | if (packet->header.packet_type != BATADV_UNICAST) | |
863 | goto out; | |
864 | ||
865 | /* Find or create a nc_path for this src-dst pair */ | |
866 | nc_path = batadv_nc_get_path(bat_priv, | |
867 | bat_priv->nc.coding_hash, | |
868 | ethhdr->h_source, | |
869 | neigh_node->addr); | |
870 | ||
871 | if (!nc_path) | |
872 | goto out; | |
873 | ||
874 | /* Add skb to nc_path */ | |
875 | packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet)); | |
876 | if (!batadv_nc_skb_add_to_path(skb, nc_path, neigh_node, packet_id)) | |
877 | goto free_nc_path; | |
878 | ||
879 | /* Packet is consumed */ | |
880 | return true; | |
881 | ||
882 | free_nc_path: | |
883 | batadv_nc_path_free_ref(nc_path); | |
884 | out: | |
885 | /* Packet is not consumed */ | |
886 | return false; | |
887 | } | |
888 | ||
d353d8d4 MH |
889 | /** |
890 | * batadv_nc_free - clean up network coding memory | |
891 | * @bat_priv: the bat priv with all the soft interface information | |
892 | */ | |
893 | void batadv_nc_free(struct batadv_priv *bat_priv) | |
894 | { | |
895 | cancel_delayed_work_sync(&bat_priv->nc.work); | |
95332477 MH |
896 | batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash, NULL); |
897 | batadv_hash_destroy(bat_priv->nc.coding_hash); | |
d353d8d4 | 898 | } |
d56b1705 MH |
899 | |
900 | /** | |
901 | * batadv_nc_nodes_seq_print_text - print the nc node information | |
902 | * @seq: seq file to print on | |
903 | * @offset: not used | |
904 | */ | |
905 | int batadv_nc_nodes_seq_print_text(struct seq_file *seq, void *offset) | |
906 | { | |
907 | struct net_device *net_dev = (struct net_device *)seq->private; | |
908 | struct batadv_priv *bat_priv = netdev_priv(net_dev); | |
909 | struct batadv_hashtable *hash = bat_priv->orig_hash; | |
910 | struct batadv_hard_iface *primary_if; | |
911 | struct hlist_head *head; | |
912 | struct batadv_orig_node *orig_node; | |
913 | struct batadv_nc_node *nc_node; | |
914 | int i; | |
915 | ||
916 | primary_if = batadv_seq_print_text_primary_if_get(seq); | |
917 | if (!primary_if) | |
918 | goto out; | |
919 | ||
920 | /* Traverse list of originators */ | |
921 | for (i = 0; i < hash->size; i++) { | |
922 | head = &hash->table[i]; | |
923 | ||
924 | /* For each orig_node in this bin */ | |
925 | rcu_read_lock(); | |
926 | hlist_for_each_entry_rcu(orig_node, head, hash_entry) { | |
927 | seq_printf(seq, "Node: %pM\n", orig_node->orig); | |
928 | ||
929 | seq_printf(seq, " Ingoing: "); | |
930 | /* For each in_nc_node to this orig_node */ | |
931 | list_for_each_entry_rcu(nc_node, | |
932 | &orig_node->in_coding_list, | |
933 | list) | |
934 | seq_printf(seq, "%pM ", | |
935 | nc_node->addr); | |
936 | seq_printf(seq, "\n"); | |
937 | ||
938 | seq_printf(seq, " Outgoing: "); | |
939 | /* For out_nc_node to this orig_node */ | |
940 | list_for_each_entry_rcu(nc_node, | |
941 | &orig_node->out_coding_list, | |
942 | list) | |
943 | seq_printf(seq, "%pM ", | |
944 | nc_node->addr); | |
945 | seq_printf(seq, "\n\n"); | |
946 | } | |
947 | rcu_read_unlock(); | |
948 | } | |
949 | ||
950 | out: | |
951 | if (primary_if) | |
952 | batadv_hardif_free_ref(primary_if); | |
953 | return 0; | |
954 | } | |
955 | ||
956 | /** | |
957 | * batadv_nc_init_debugfs - create nc folder and related files in debugfs | |
958 | * @bat_priv: the bat priv with all the soft interface information | |
959 | */ | |
960 | int batadv_nc_init_debugfs(struct batadv_priv *bat_priv) | |
961 | { | |
962 | struct dentry *nc_dir, *file; | |
963 | ||
964 | nc_dir = debugfs_create_dir("nc", bat_priv->debug_dir); | |
965 | if (!nc_dir) | |
966 | goto out; | |
967 | ||
968 | file = debugfs_create_u8("min_tq", S_IRUGO | S_IWUSR, nc_dir, | |
969 | &bat_priv->nc.min_tq); | |
970 | if (!file) | |
971 | goto out; | |
972 | ||
95332477 MH |
973 | file = debugfs_create_u32("max_fwd_delay", S_IRUGO | S_IWUSR, nc_dir, |
974 | &bat_priv->nc.max_fwd_delay); | |
975 | if (!file) | |
976 | goto out; | |
977 | ||
d56b1705 MH |
978 | return 0; |
979 | ||
980 | out: | |
981 | return -ENOMEM; | |
982 | } |