blob: 3c72557df45adee87cba306b2d560089e71cdb49 [file] [log] [blame]
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +01001/*
2 * Copyright (c) 2008 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10#include <linux/etherdevice.h>
11#include <linux/list.h>
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +010012#include <linux/random.h>
13#include <linux/spinlock.h>
14#include <linux/string.h>
15#include <net/mac80211.h>
16#include "ieee80211_i.h"
17#include "mesh.h"
18
19/* There will be initially 2^INIT_PATHS_SIZE_ORDER buckets */
20#define INIT_PATHS_SIZE_ORDER 2
21
22/* Keep the mean chain length below this constant */
23#define MEAN_CHAIN_LEN 2
24
25#define MPATH_EXPIRED(mpath) ((mpath->flags & MESH_PATH_ACTIVE) && \
26 time_after(jiffies, mpath->exp_time) && \
27 !(mpath->flags & MESH_PATH_FIXED))
28
29struct mpath_node {
30 struct hlist_node list;
31 struct rcu_head rcu;
32 /* This indirection allows two different tables to point to the same
33 * mesh_path structure, useful when resizing
34 */
35 struct mesh_path *mpath;
36};
37
38static struct mesh_table *mesh_paths;
YanBo79617de2008-09-22 13:30:32 +080039static struct mesh_table *mpp_paths; /* Store paths for MPP&MAP */
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +010040
41/* This lock will have the grow table function as writer and add / delete nodes
42 * as readers. When reading the table (i.e. doing lookups) we are well protected
43 * by RCU
44 */
45static DEFINE_RWLOCK(pathtbl_resize_lock);
46
47/**
48 *
49 * mesh_path_assign_nexthop - update mesh path next hop
50 *
51 * @mpath: mesh path to update
52 * @sta: next hop to assign
53 *
54 * Locking: mpath->state_lock must be held when calling this function
55 */
56void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
57{
Johannes Bergd0709a62008-02-25 16:27:46 +010058 rcu_assign_pointer(mpath->next_hop, sta);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +010059}
60
61
62/**
63 * mesh_path_lookup - look up a path in the mesh path table
64 * @dst: hardware address (ETH_ALEN length) of destination
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +120065 * @sdata: local subif
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +010066 *
67 * Returns: pointer to the mesh path structure, or NULL if not found
68 *
69 * Locking: must be called within a read rcu section.
70 */
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +120071struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +010072{
73 struct mesh_path *mpath;
74 struct hlist_node *n;
75 struct hlist_head *bucket;
76 struct mesh_table *tbl;
77 struct mpath_node *node;
78
79 tbl = rcu_dereference(mesh_paths);
80
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +120081 bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +010082 hlist_for_each_entry_rcu(node, n, bucket, list) {
83 mpath = node->mpath;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +120084 if (mpath->sdata == sdata &&
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +010085 memcmp(dst, mpath->dst, ETH_ALEN) == 0) {
86 if (MPATH_EXPIRED(mpath)) {
87 spin_lock_bh(&mpath->state_lock);
88 if (MPATH_EXPIRED(mpath))
89 mpath->flags &= ~MESH_PATH_ACTIVE;
90 spin_unlock_bh(&mpath->state_lock);
91 }
92 return mpath;
93 }
94 }
95 return NULL;
96}
97
YanBo79617de2008-09-22 13:30:32 +080098struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
99{
100 struct mesh_path *mpath;
101 struct hlist_node *n;
102 struct hlist_head *bucket;
103 struct mesh_table *tbl;
104 struct mpath_node *node;
105
106 tbl = rcu_dereference(mpp_paths);
107
108 bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
109 hlist_for_each_entry_rcu(node, n, bucket, list) {
110 mpath = node->mpath;
111 if (mpath->sdata == sdata &&
112 memcmp(dst, mpath->dst, ETH_ALEN) == 0) {
113 if (MPATH_EXPIRED(mpath)) {
114 spin_lock_bh(&mpath->state_lock);
115 if (MPATH_EXPIRED(mpath))
116 mpath->flags &= ~MESH_PATH_ACTIVE;
117 spin_unlock_bh(&mpath->state_lock);
118 }
119 return mpath;
120 }
121 }
122 return NULL;
123}
124
125
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100126/**
127 * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
128 * @idx: index
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200129 * @sdata: local subif, or NULL for all entries
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100130 *
131 * Returns: pointer to the mesh path structure, or NULL if not found.
132 *
133 * Locking: must be called within a read rcu section.
134 */
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200135struct mesh_path *mesh_path_lookup_by_idx(int idx, struct ieee80211_sub_if_data *sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100136{
137 struct mpath_node *node;
138 struct hlist_node *p;
139 int i;
140 int j = 0;
141
Luis Carlos Cobo2a8ca292008-02-29 17:51:25 -0800142 for_each_mesh_entry(mesh_paths, p, node, i) {
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200143 if (sdata && node->mpath->sdata != sdata)
Luis Carlos Cobo2a8ca292008-02-29 17:51:25 -0800144 continue;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100145 if (j++ == idx) {
146 if (MPATH_EXPIRED(node->mpath)) {
147 spin_lock_bh(&node->mpath->state_lock);
148 if (MPATH_EXPIRED(node->mpath))
149 node->mpath->flags &= ~MESH_PATH_ACTIVE;
150 spin_unlock_bh(&node->mpath->state_lock);
151 }
152 return node->mpath;
153 }
Luis Carlos Cobo2a8ca292008-02-29 17:51:25 -0800154 }
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100155
156 return NULL;
157}
158
159/**
160 * mesh_path_add - allocate and add a new path to the mesh path table
161 * @addr: destination address of the path (ETH_ALEN length)
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200162 * @sdata: local subif
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100163 *
164 * Returns: 0 on sucess
165 *
166 * State: the initial state of the new path is set to 0
167 */
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200168int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100169{
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100170 struct mesh_path *mpath, *new_mpath;
171 struct mpath_node *node, *new_node;
172 struct hlist_head *bucket;
173 struct hlist_node *n;
174 int grow = 0;
175 int err = 0;
176 u32 hash_idx;
177
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200178 if (memcmp(dst, sdata->dev->dev_addr, ETH_ALEN) == 0)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100179 /* never add ourselves as neighbours */
180 return -ENOTSUPP;
181
182 if (is_multicast_ether_addr(dst))
183 return -ENOTSUPP;
184
Johannes Berg472dbc42008-09-11 00:01:49 +0200185 if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100186 return -ENOSPC;
187
Pavel Emelyanov402d7752008-05-06 18:53:43 +0400188 err = -ENOMEM;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100189 new_mpath = kzalloc(sizeof(struct mesh_path), GFP_KERNEL);
Pavel Emelyanov402d7752008-05-06 18:53:43 +0400190 if (!new_mpath)
191 goto err_path_alloc;
192
Pavel Emelyanov0eb03d52008-05-06 18:49:02 +0400193 new_node = kmalloc(sizeof(struct mpath_node), GFP_KERNEL);
Pavel Emelyanov402d7752008-05-06 18:53:43 +0400194 if (!new_node)
195 goto err_node_alloc;
Pavel Emelyanovf84e71a2008-05-06 18:46:36 +0400196
197 read_lock(&pathtbl_resize_lock);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100198 memcpy(new_mpath->dst, dst, ETH_ALEN);
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200199 new_mpath->sdata = sdata;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100200 new_mpath->flags = 0;
201 skb_queue_head_init(&new_mpath->frame_queue);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100202 new_node->mpath = new_mpath;
203 new_mpath->timer.data = (unsigned long) new_mpath;
204 new_mpath->timer.function = mesh_path_timer;
205 new_mpath->exp_time = jiffies;
206 spin_lock_init(&new_mpath->state_lock);
207 init_timer(&new_mpath->timer);
208
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200209 hash_idx = mesh_table_hash(dst, sdata, mesh_paths);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100210 bucket = &mesh_paths->hash_buckets[hash_idx];
211
212 spin_lock(&mesh_paths->hashwlock[hash_idx]);
213
Pavel Emelyanov402d7752008-05-06 18:53:43 +0400214 err = -EEXIST;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100215 hlist_for_each_entry(node, n, bucket, list) {
216 mpath = node->mpath;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200217 if (mpath->sdata == sdata && memcmp(dst, mpath->dst, ETH_ALEN) == 0)
Pavel Emelyanov402d7752008-05-06 18:53:43 +0400218 goto err_exists;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100219 }
220
221 hlist_add_head_rcu(&new_node->list, bucket);
222 if (atomic_inc_return(&mesh_paths->entries) >=
223 mesh_paths->mean_chain_len * (mesh_paths->hash_mask + 1))
224 grow = 1;
225
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100226 spin_unlock(&mesh_paths->hashwlock[hash_idx]);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100227 read_unlock(&pathtbl_resize_lock);
Pavel Emelyanov402d7752008-05-06 18:53:43 +0400228 if (grow) {
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100229 struct mesh_table *oldtbl, *newtbl;
230
231 write_lock(&pathtbl_resize_lock);
232 oldtbl = mesh_paths;
233 newtbl = mesh_table_grow(mesh_paths);
234 if (!newtbl) {
235 write_unlock(&pathtbl_resize_lock);
Pavel Emelyanov3282aea2008-05-07 19:54:04 +0400236 return 0;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100237 }
238 rcu_assign_pointer(mesh_paths, newtbl);
Pavel Emelyanov6d6936e2008-05-06 18:51:31 +0400239 write_unlock(&pathtbl_resize_lock);
240
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100241 synchronize_rcu();
242 mesh_table_free(oldtbl, false);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100243 }
Pavel Emelyanov402d7752008-05-06 18:53:43 +0400244 return 0;
245
246err_exists:
247 spin_unlock(&mesh_paths->hashwlock[hash_idx]);
248 read_unlock(&pathtbl_resize_lock);
249 kfree(new_node);
250err_node_alloc:
251 kfree(new_mpath);
252err_path_alloc:
Johannes Berg472dbc42008-09-11 00:01:49 +0200253 atomic_dec(&sdata->u.mesh.mpaths);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100254 return err;
255}
256
257
YanBo79617de2008-09-22 13:30:32 +0800258int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
259{
260 struct mesh_path *mpath, *new_mpath;
261 struct mpath_node *node, *new_node;
262 struct hlist_head *bucket;
263 struct hlist_node *n;
264 int grow = 0;
265 int err = 0;
266 u32 hash_idx;
267
268
269 if (memcmp(dst, sdata->dev->dev_addr, ETH_ALEN) == 0)
270 /* never add ourselves as neighbours */
271 return -ENOTSUPP;
272
273 if (is_multicast_ether_addr(dst))
274 return -ENOTSUPP;
275
276 err = -ENOMEM;
277 new_mpath = kzalloc(sizeof(struct mesh_path), GFP_KERNEL);
278 if (!new_mpath)
279 goto err_path_alloc;
280
281 new_node = kmalloc(sizeof(struct mpath_node), GFP_KERNEL);
282 if (!new_node)
283 goto err_node_alloc;
284
285 read_lock(&pathtbl_resize_lock);
286 memcpy(new_mpath->dst, dst, ETH_ALEN);
287 memcpy(new_mpath->mpp, mpp, ETH_ALEN);
288 new_mpath->sdata = sdata;
289 new_mpath->flags = 0;
290 skb_queue_head_init(&new_mpath->frame_queue);
291 new_node->mpath = new_mpath;
292 new_mpath->exp_time = jiffies;
293 spin_lock_init(&new_mpath->state_lock);
294
295 hash_idx = mesh_table_hash(dst, sdata, mpp_paths);
296 bucket = &mpp_paths->hash_buckets[hash_idx];
297
298 spin_lock(&mpp_paths->hashwlock[hash_idx]);
299
300 err = -EEXIST;
301 hlist_for_each_entry(node, n, bucket, list) {
302 mpath = node->mpath;
303 if (mpath->sdata == sdata && memcmp(dst, mpath->dst, ETH_ALEN) == 0)
304 goto err_exists;
305 }
306
307 hlist_add_head_rcu(&new_node->list, bucket);
308 if (atomic_inc_return(&mpp_paths->entries) >=
309 mpp_paths->mean_chain_len * (mpp_paths->hash_mask + 1))
310 grow = 1;
311
312 spin_unlock(&mpp_paths->hashwlock[hash_idx]);
313 read_unlock(&pathtbl_resize_lock);
314 if (grow) {
315 struct mesh_table *oldtbl, *newtbl;
316
317 write_lock(&pathtbl_resize_lock);
318 oldtbl = mpp_paths;
319 newtbl = mesh_table_grow(mpp_paths);
320 if (!newtbl) {
321 write_unlock(&pathtbl_resize_lock);
322 return 0;
323 }
324 rcu_assign_pointer(mpp_paths, newtbl);
325 write_unlock(&pathtbl_resize_lock);
326
327 synchronize_rcu();
328 mesh_table_free(oldtbl, false);
329 }
330 return 0;
331
332err_exists:
333 spin_unlock(&mpp_paths->hashwlock[hash_idx]);
334 read_unlock(&pathtbl_resize_lock);
335 kfree(new_node);
336err_node_alloc:
337 kfree(new_mpath);
338err_path_alloc:
339 return err;
340}
341
342
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100343/**
344 * mesh_plink_broken - deactivates paths and sends perr when a link breaks
345 *
346 * @sta: broken peer link
347 *
348 * This function must be called from the rate control algorithm if enough
349 * delivery errors suggest that a peer link is no longer usable.
350 */
351void mesh_plink_broken(struct sta_info *sta)
352{
353 struct mesh_path *mpath;
354 struct mpath_node *node;
355 struct hlist_node *p;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200356 struct ieee80211_sub_if_data *sdata = sta->sdata;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100357 int i;
358
359 rcu_read_lock();
360 for_each_mesh_entry(mesh_paths, p, node, i) {
361 mpath = node->mpath;
362 spin_lock_bh(&mpath->state_lock);
363 if (mpath->next_hop == sta &&
364 mpath->flags & MESH_PATH_ACTIVE &&
365 !(mpath->flags & MESH_PATH_FIXED)) {
366 mpath->flags &= ~MESH_PATH_ACTIVE;
367 ++mpath->dsn;
368 spin_unlock_bh(&mpath->state_lock);
369 mesh_path_error_tx(mpath->dst,
370 cpu_to_le32(mpath->dsn),
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200371 sdata->dev->broadcast, sdata);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100372 } else
373 spin_unlock_bh(&mpath->state_lock);
374 }
375 rcu_read_unlock();
376}
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100377
378/**
379 * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
380 *
381 * @sta - mesh peer to match
382 *
Luis Carlos Cobob4e08ea2008-02-29 15:46:08 -0800383 * RCU notes: this function is called when a mesh plink transitions from
384 * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
385 * allows path creation. This will happen before the sta can be freed (because
Johannes Bergd0709a62008-02-25 16:27:46 +0100386 * sta_info_destroy() calls this) so any reader in a rcu read block will be
387 * protected against the plink disappearing.
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100388 */
389void mesh_path_flush_by_nexthop(struct sta_info *sta)
390{
391 struct mesh_path *mpath;
392 struct mpath_node *node;
393 struct hlist_node *p;
394 int i;
395
396 for_each_mesh_entry(mesh_paths, p, node, i) {
397 mpath = node->mpath;
398 if (mpath->next_hop == sta)
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200399 mesh_path_del(mpath->dst, mpath->sdata);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100400 }
401}
402
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200403void mesh_path_flush(struct ieee80211_sub_if_data *sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100404{
405 struct mesh_path *mpath;
406 struct mpath_node *node;
407 struct hlist_node *p;
408 int i;
409
410 for_each_mesh_entry(mesh_paths, p, node, i) {
411 mpath = node->mpath;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200412 if (mpath->sdata == sdata)
413 mesh_path_del(mpath->dst, mpath->sdata);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100414 }
415}
416
417static void mesh_path_node_reclaim(struct rcu_head *rp)
418{
419 struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200420 struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
Johannes Bergd0709a62008-02-25 16:27:46 +0100421
Luis Carlos Cobo89a1ad62008-02-29 14:49:37 -0800422 del_timer_sync(&node->mpath->timer);
Johannes Berg472dbc42008-09-11 00:01:49 +0200423 atomic_dec(&sdata->u.mesh.mpaths);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100424 kfree(node->mpath);
425 kfree(node);
426}
427
428/**
429 * mesh_path_del - delete a mesh path from the table
430 *
431 * @addr: dst address (ETH_ALEN length)
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200432 * @sdata: local subif
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100433 *
434 * Returns: 0 if succesful
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100435 */
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200436int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100437{
438 struct mesh_path *mpath;
439 struct mpath_node *node;
440 struct hlist_head *bucket;
441 struct hlist_node *n;
442 int hash_idx;
443 int err = 0;
444
445 read_lock(&pathtbl_resize_lock);
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200446 hash_idx = mesh_table_hash(addr, sdata, mesh_paths);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100447 bucket = &mesh_paths->hash_buckets[hash_idx];
448
449 spin_lock(&mesh_paths->hashwlock[hash_idx]);
450 hlist_for_each_entry(node, n, bucket, list) {
451 mpath = node->mpath;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200452 if (mpath->sdata == sdata &&
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100453 memcmp(addr, mpath->dst, ETH_ALEN) == 0) {
454 spin_lock_bh(&mpath->state_lock);
Luis Carlos Cobocfa22c72008-02-29 15:04:13 -0800455 mpath->flags |= MESH_PATH_RESOLVING;
456 hlist_del_rcu(&node->list);
457 call_rcu(&node->rcu, mesh_path_node_reclaim);
458 atomic_dec(&mesh_paths->entries);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100459 spin_unlock_bh(&mpath->state_lock);
460 goto enddel;
461 }
462 }
463
464 err = -ENXIO;
465enddel:
466 spin_unlock(&mesh_paths->hashwlock[hash_idx]);
467 read_unlock(&pathtbl_resize_lock);
468 return err;
469}
470
471/**
472 * mesh_path_tx_pending - sends pending frames in a mesh path queue
473 *
474 * @mpath: mesh path to activate
475 *
476 * Locking: the state_lock of the mpath structure must NOT be held when calling
477 * this function.
478 */
479void mesh_path_tx_pending(struct mesh_path *mpath)
480{
481 struct sk_buff *skb;
482
483 while ((skb = skb_dequeue(&mpath->frame_queue)) &&
484 (mpath->flags & MESH_PATH_ACTIVE))
485 dev_queue_xmit(skb);
486}
487
488/**
489 * mesh_path_discard_frame - discard a frame whose path could not be resolved
490 *
491 * @skb: frame to discard
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200492 * @sdata: network subif the frame was to be sent through
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100493 *
494 * If the frame was beign forwarded from another MP, a PERR frame will be sent
495 * to the precursor.
496 *
497 * Locking: the function must me called within a rcu_read_lock region
498 */
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200499void mesh_path_discard_frame(struct sk_buff *skb,
500 struct ieee80211_sub_if_data *sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100501{
Luis Carlos Coboe32f85f2008-08-05 19:34:52 +0200502 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100503 struct mesh_path *mpath;
504 u32 dsn = 0;
505
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200506 if (memcmp(hdr->addr4, sdata->dev->dev_addr, ETH_ALEN) != 0) {
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100507 u8 *ra, *da;
508
Luis Carlos Coboe32f85f2008-08-05 19:34:52 +0200509 da = hdr->addr3;
510 ra = hdr->addr2;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200511 mpath = mesh_path_lookup(da, sdata);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100512 if (mpath)
513 dsn = ++mpath->dsn;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200514 mesh_path_error_tx(skb->data, cpu_to_le32(dsn), ra, sdata);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100515 }
516
517 kfree_skb(skb);
Johannes Berg472dbc42008-09-11 00:01:49 +0200518 sdata->u.mesh.mshstats.dropped_frames_no_route++;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100519}
520
521/**
522 * mesh_path_flush_pending - free the pending queue of a mesh path
523 *
524 * @mpath: mesh path whose queue has to be freed
525 *
526 * Locking: the function must me called withing a rcu_read_lock region
527 */
528void mesh_path_flush_pending(struct mesh_path *mpath)
529{
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100530 struct sk_buff *skb;
531
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100532 while ((skb = skb_dequeue(&mpath->frame_queue)) &&
533 (mpath->flags & MESH_PATH_ACTIVE))
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200534 mesh_path_discard_frame(skb, mpath->sdata);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100535}
536
537/**
538 * mesh_path_fix_nexthop - force a specific next hop for a mesh path
539 *
540 * @mpath: the mesh path to modify
541 * @next_hop: the next hop to force
542 *
543 * Locking: this function must be called holding mpath->state_lock
544 */
545void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
546{
547 spin_lock_bh(&mpath->state_lock);
548 mesh_path_assign_nexthop(mpath, next_hop);
549 mpath->dsn = 0xffff;
550 mpath->metric = 0;
551 mpath->hop_count = 0;
552 mpath->exp_time = 0;
553 mpath->flags |= MESH_PATH_FIXED;
554 mesh_path_activate(mpath);
555 spin_unlock_bh(&mpath->state_lock);
556 mesh_path_tx_pending(mpath);
557}
558
559static void mesh_path_node_free(struct hlist_node *p, bool free_leafs)
560{
561 struct mesh_path *mpath;
562 struct mpath_node *node = hlist_entry(p, struct mpath_node, list);
563 mpath = node->mpath;
564 hlist_del_rcu(p);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100565 if (free_leafs)
566 kfree(mpath);
567 kfree(node);
568}
569
Pavel Emelyanov4caf86c2008-05-07 19:47:01 +0400570static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100571{
572 struct mesh_path *mpath;
573 struct mpath_node *node, *new_node;
574 u32 hash_idx;
575
Pavel Emelyanov8566dc32008-05-07 19:51:51 +0400576 new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
Pavel Emelyanov00242c42008-05-07 19:48:14 +0400577 if (new_node == NULL)
578 return -ENOMEM;
579
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100580 node = hlist_entry(p, struct mpath_node, list);
581 mpath = node->mpath;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100582 new_node->mpath = mpath;
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200583 hash_idx = mesh_table_hash(mpath->dst, mpath->sdata, newtbl);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100584 hlist_add_head(&new_node->list,
585 &newtbl->hash_buckets[hash_idx]);
Pavel Emelyanov4caf86c2008-05-07 19:47:01 +0400586 return 0;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100587}
588
589int mesh_pathtbl_init(void)
590{
591 mesh_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
YanBo79617de2008-09-22 13:30:32 +0800592 if (!mesh_paths)
593 return -ENOMEM;
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100594 mesh_paths->free_node = &mesh_path_node_free;
595 mesh_paths->copy_node = &mesh_path_node_copy;
596 mesh_paths->mean_chain_len = MEAN_CHAIN_LEN;
YanBo79617de2008-09-22 13:30:32 +0800597
598 mpp_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
599 if (!mpp_paths) {
600 mesh_table_free(mesh_paths, true);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100601 return -ENOMEM;
YanBo79617de2008-09-22 13:30:32 +0800602 }
603 mpp_paths->free_node = &mesh_path_node_free;
604 mpp_paths->copy_node = &mesh_path_node_copy;
605 mpp_paths->mean_chain_len = MEAN_CHAIN_LEN;
606
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100607 return 0;
608}
609
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200610void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100611{
612 struct mesh_path *mpath;
613 struct mpath_node *node;
614 struct hlist_node *p;
615 int i;
616
617 read_lock(&pathtbl_resize_lock);
618 for_each_mesh_entry(mesh_paths, p, node, i) {
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200619 if (node->mpath->sdata != sdata)
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100620 continue;
621 mpath = node->mpath;
622 spin_lock_bh(&mpath->state_lock);
623 if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
624 (!(mpath->flags & MESH_PATH_FIXED)) &&
625 time_after(jiffies,
626 mpath->exp_time + MESH_PATH_EXPIRE)) {
627 spin_unlock_bh(&mpath->state_lock);
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200628 mesh_path_del(mpath->dst, mpath->sdata);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100629 } else
630 spin_unlock_bh(&mpath->state_lock);
631 }
632 read_unlock(&pathtbl_resize_lock);
633}
634
635void mesh_pathtbl_unregister(void)
636{
637 mesh_table_free(mesh_paths, true);
YanBo79617de2008-09-22 13:30:32 +0800638 mesh_table_free(mpp_paths, true);
Luis Carlos Coboeb2b9312008-02-23 15:17:14 +0100639}