net/mac80211/mesh_pathtbl.c

   1 /*
   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>
  12 #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
  29 struct 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
  38 static struct mesh_table *mesh_paths;
  39 static struct mesh_table *mpp_paths; /* Store paths for MPP&MAP */
  40
  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  */
  45 static 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  */
  56 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
  57 {
  58         rcu_assign_pointer(mpath->next_hop, sta);
  59 }
  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
  65  * @sdata: local subif
  66  *
  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  */
  71 struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
  72 {
  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
  81         bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
  82         hlist_for_each_entry_rcu(node, n, bucket, list) {
  83                 mpath = node->mpath;
  84                 if (mpath->sdata == sdata &&
  85                                 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
  98 struct 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
 126 /**
 127  * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
 128  * @idx: index
 129  * @sdata: local subif, or NULL for all entries
 130  *
 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  */
 135 struct mesh_path *mesh_path_lookup_by_idx(int idx, struct ieee80211_sub_if_data *sdata)
 136 {
 137         struct mpath_node *node;
 138         struct hlist_node *p;
 139         int i;
 140         int j = 0;
 141
 142         for_each_mesh_entry(mesh_paths, p, node, i) {
 143                 if (sdata && node->mpath->sdata != sdata)
 144                         continue;
 145                 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                 }
 154         }
 155
 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)
 162  * @sdata: local subif
 163  *
 164  * Returns: 0 on sucess
 165  *
 166  * State: the initial state of the new path is set to 0
 167  */
 168 int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
 169 {
 170         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
 178         if (memcmp(dst, sdata->dev->dev_addr, ETH_ALEN) == 0)
 179                 /* never add ourselves as neighbours */
 180                 return -ENOTSUPP;
 181
 182         if (is_multicast_ether_addr(dst))
 183                 return -ENOTSUPP;
 184
 185         if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
 186                 return -ENOSPC;
 187
 188         err = -ENOMEM;
 189         new_mpath = kzalloc(sizeof(struct mesh_path), GFP_KERNEL);
 190         if (!new_mpath)
 191                 goto err_path_alloc;
 192
 193         new_node = kmalloc(sizeof(struct mpath_node), GFP_KERNEL);
 194         if (!new_node)
 195                 goto err_node_alloc;
 196
 197         read_lock(&pathtbl_resize_lock);
 198         memcpy(new_mpath->dst, dst, ETH_ALEN);
 199         new_mpath->sdata = sdata;
 200         new_mpath->flags = 0;
 201         skb_queue_head_init(&new_mpath->frame_queue);
 202         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
 209         hash_idx = mesh_table_hash(dst, sdata, mesh_paths);
 210         bucket = &mesh_paths->hash_buckets[hash_idx];
 211
 212         spin_lock(&mesh_paths->hashwlock[hash_idx]);
 213
 214         err = -EEXIST;
 215         hlist_for_each_entry(node, n, bucket, list) {
 216                 mpath = node->mpath;
 217                 if (mpath->sdata == sdata && memcmp(dst, mpath->dst, ETH_ALEN) == 0)
 218                         goto err_exists;
 219         }
 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
 226         spin_unlock(&mesh_paths->hashwlock[hash_idx]);
 227         read_unlock(&pathtbl_resize_lock);
 228         if (grow) {
 229                 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);
 236                         return 0;
 237                 }
 238                 rcu_assign_pointer(mesh_paths, newtbl);
 239                 write_unlock(&pathtbl_resize_lock);
 240
 241                 synchronize_rcu();
 242                 mesh_table_free(oldtbl, false);
 243         }
 244         return 0;
 245
 246 err_exists:
 247         spin_unlock(&mesh_paths->hashwlock[hash_idx]);
 248         read_unlock(&pathtbl_resize_lock);
 249         kfree(new_node);
 250 err_node_alloc:
 251         kfree(new_mpath);
 252 err_path_alloc:
 253         atomic_dec(&sdata->u.mesh.mpaths);
 254         return err;
 255 }
 256
 257
 258 int 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
 332 err_exists:
 333         spin_unlock(&mpp_paths->hashwlock[hash_idx]);
 334         read_unlock(&pathtbl_resize_lock);
 335         kfree(new_node);
 336 err_node_alloc:
 337         kfree(new_mpath);
 338 err_path_alloc:
 339         return err;
 340 }
 341
 342
 343 /**
 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  */
 351 void mesh_plink_broken(struct sta_info *sta)
 352 {
 353         struct mesh_path *mpath;
 354         struct mpath_node *node;
 355         struct hlist_node *p;
 356         struct ieee80211_sub_if_data *sdata = sta->sdata;
 357         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),
 371                                         sdata->dev->broadcast, sdata);
 372                 } else
 373                 spin_unlock_bh(&mpath->state_lock);
 374         }
 375         rcu_read_unlock();
 376 }
 377
 378 /**
 379  * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
 380  *
 381  * @sta - mesh peer to match
 382  *
 383  * 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
 386  * sta_info_destroy() calls this) so any reader in a rcu read block will be
 387  * protected against the plink disappearing.
 388  */
 389 void 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)
 399                         mesh_path_del(mpath->dst, mpath->sdata);
 400         }
 401 }
 402
 403 void mesh_path_flush(struct ieee80211_sub_if_data *sdata)
 404 {
 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;
 412                 if (mpath->sdata == sdata)
 413                         mesh_path_del(mpath->dst, mpath->sdata);
 414         }
 415 }
 416
 417 static void mesh_path_node_reclaim(struct rcu_head *rp)
 418 {
 419         struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
 420         struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
 421
 422         del_timer_sync(&node->mpath->timer);
 423         atomic_dec(&sdata->u.mesh.mpaths);
 424         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)
 432  * @sdata: local subif
 433  *
 434  * Returns: 0 if succesful
 435  */
 436 int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
 437 {
 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);
 446         hash_idx = mesh_table_hash(addr, sdata, mesh_paths);
 447         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;
 452                 if (mpath->sdata == sdata &&
 453                                 memcmp(addr, mpath->dst, ETH_ALEN) == 0) {
 454                         spin_lock_bh(&mpath->state_lock);
 455                         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);
 459                         spin_unlock_bh(&mpath->state_lock);
 460                         goto enddel;
 461                 }
 462         }
 463
 464         err = -ENXIO;
 465 enddel:
 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  */
 479 void 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
 492  * @sdata: network subif the frame was to be sent through
 493  *
 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  */
 499 void mesh_path_discard_frame(struct sk_buff *skb,
 500                              struct ieee80211_sub_if_data *sdata)
 501 {
 502         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 503         struct mesh_path *mpath;
 504         u32 dsn = 0;
 505
 506         if (memcmp(hdr->addr4, sdata->dev->dev_addr, ETH_ALEN) != 0) {
 507                 u8 *ra, *da;
 508
 509                 da = hdr->addr3;
 510                 ra = hdr->addr2;
 511                 mpath = mesh_path_lookup(da, sdata);
 512                 if (mpath)
 513                         dsn = ++mpath->dsn;
 514                 mesh_path_error_tx(skb->data, cpu_to_le32(dsn), ra, sdata);
 515         }
 516
 517         kfree_skb(skb);
 518         sdata->u.mesh.mshstats.dropped_frames_no_route++;
 519 }
 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  */
 528 void mesh_path_flush_pending(struct mesh_path *mpath)
 529 {
 530         struct sk_buff *skb;
 531
 532         while ((skb = skb_dequeue(&mpath->frame_queue)) &&
 533                         (mpath->flags & MESH_PATH_ACTIVE))
 534                 mesh_path_discard_frame(skb, mpath->sdata);
 535 }
 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  */
 545 void 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
 559 static 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);
 565         if (free_leafs)
 566                 kfree(mpath);
 567         kfree(node);
 568 }
 569
 570 static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
 571 {
 572         struct mesh_path *mpath;
 573         struct mpath_node *node, *new_node;
 574         u32 hash_idx;
 575
 576         new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
 577         if (new_node == NULL)
 578                 return -ENOMEM;
 579
 580         node = hlist_entry(p, struct mpath_node, list);
 581         mpath = node->mpath;
 582         new_node->mpath = mpath;
 583         hash_idx = mesh_table_hash(mpath->dst, mpath->sdata, newtbl);
 584         hlist_add_head(&new_node->list,
 585                         &newtbl->hash_buckets[hash_idx]);
 586         return 0;
 587 }
 588
 589 int mesh_pathtbl_init(void)
 590 {
 591         mesh_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
 592         if (!mesh_paths)
 593                 return -ENOMEM;
 594         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;
 597
 598         mpp_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
 599         if (!mpp_paths) {
 600                 mesh_table_free(mesh_paths, true);
 601                 return -ENOMEM;
 602         }
 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
 607         return 0;
 608 }
 609
 610 void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
 611 {
 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) {
 619                 if (node->mpath->sdata != sdata)
 620                         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);
 628                         mesh_path_del(mpath->dst, mpath->sdata);
 629                 } else
 630                         spin_unlock_bh(&mpath->state_lock);
 631         }
 632         read_unlock(&pathtbl_resize_lock);
 633 }
 634
 635 void mesh_pathtbl_unregister(void)
 636 {
 637         mesh_table_free(mesh_paths, true);
 638         mesh_table_free(mpp_paths, true);
 639 }