| 1 | /* |
| 2 | * Copyright (c) 2008, 2009 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/slab.h> |
| 14 | #include <linux/spinlock.h> |
| 15 | #include <linux/string.h> |
| 16 | #include <net/mac80211.h> |
| 17 | #include "wme.h" |
| 18 | #include "ieee80211_i.h" |
| 19 | #include "mesh.h" |
| 20 | |
| 21 | /* There will be initially 2^INIT_PATHS_SIZE_ORDER buckets */ |
| 22 | #define INIT_PATHS_SIZE_ORDER 2 |
| 23 | |
| 24 | /* Keep the mean chain length below this constant */ |
| 25 | #define MEAN_CHAIN_LEN 2 |
| 26 | |
| 27 | static inline bool mpath_expired(struct mesh_path *mpath) |
| 28 | { |
| 29 | return (mpath->flags & MESH_PATH_ACTIVE) && |
| 30 | time_after(jiffies, mpath->exp_time) && |
| 31 | !(mpath->flags & MESH_PATH_FIXED); |
| 32 | } |
| 33 | |
| 34 | struct mpath_node { |
| 35 | struct hlist_node list; |
| 36 | struct rcu_head rcu; |
| 37 | /* This indirection allows two different tables to point to the same |
| 38 | * mesh_path structure, useful when resizing |
| 39 | */ |
| 40 | struct mesh_path *mpath; |
| 41 | }; |
| 42 | |
| 43 | static struct mesh_table __rcu *mesh_paths; |
| 44 | static struct mesh_table __rcu *mpp_paths; /* Store paths for MPP&MAP */ |
| 45 | |
| 46 | int mesh_paths_generation; |
| 47 | int mpp_paths_generation; |
| 48 | |
| 49 | /* This lock will have the grow table function as writer and add / delete nodes |
| 50 | * as readers. RCU provides sufficient protection only when reading the table |
| 51 | * (i.e. doing lookups). Adding or adding or removing nodes requires we take |
| 52 | * the read lock or we risk operating on an old table. The write lock is only |
| 53 | * needed when modifying the number of buckets a table. |
| 54 | */ |
| 55 | static DEFINE_RWLOCK(pathtbl_resize_lock); |
| 56 | |
| 57 | |
| 58 | static inline struct mesh_table *resize_dereference_paths( |
| 59 | struct mesh_table __rcu *table) |
| 60 | { |
| 61 | return rcu_dereference_protected(table, |
| 62 | lockdep_is_held(&pathtbl_resize_lock)); |
| 63 | } |
| 64 | |
| 65 | static inline struct mesh_table *resize_dereference_mesh_paths(void) |
| 66 | { |
| 67 | return resize_dereference_paths(mesh_paths); |
| 68 | } |
| 69 | |
| 70 | static inline struct mesh_table *resize_dereference_mpp_paths(void) |
| 71 | { |
| 72 | return resize_dereference_paths(mpp_paths); |
| 73 | } |
| 74 | |
| 75 | /* |
| 76 | * CAREFUL -- "tbl" must not be an expression, |
| 77 | * in particular not an rcu_dereference(), since |
| 78 | * it's used twice. So it is illegal to do |
| 79 | * for_each_mesh_entry(rcu_dereference(...), ...) |
| 80 | */ |
| 81 | #define for_each_mesh_entry(tbl, node, i) \ |
| 82 | for (i = 0; i <= tbl->hash_mask; i++) \ |
| 83 | hlist_for_each_entry_rcu(node, &tbl->hash_buckets[i], list) |
| 84 | |
| 85 | |
| 86 | static struct mesh_table *mesh_table_alloc(int size_order) |
| 87 | { |
| 88 | int i; |
| 89 | struct mesh_table *newtbl; |
| 90 | |
| 91 | newtbl = kmalloc(sizeof(struct mesh_table), GFP_ATOMIC); |
| 92 | if (!newtbl) |
| 93 | return NULL; |
| 94 | |
| 95 | newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) * |
| 96 | (1 << size_order), GFP_ATOMIC); |
| 97 | |
| 98 | if (!newtbl->hash_buckets) { |
| 99 | kfree(newtbl); |
| 100 | return NULL; |
| 101 | } |
| 102 | |
| 103 | newtbl->hashwlock = kmalloc(sizeof(spinlock_t) * |
| 104 | (1 << size_order), GFP_ATOMIC); |
| 105 | if (!newtbl->hashwlock) { |
| 106 | kfree(newtbl->hash_buckets); |
| 107 | kfree(newtbl); |
| 108 | return NULL; |
| 109 | } |
| 110 | |
| 111 | newtbl->size_order = size_order; |
| 112 | newtbl->hash_mask = (1 << size_order) - 1; |
| 113 | atomic_set(&newtbl->entries, 0); |
| 114 | get_random_bytes(&newtbl->hash_rnd, |
| 115 | sizeof(newtbl->hash_rnd)); |
| 116 | for (i = 0; i <= newtbl->hash_mask; i++) |
| 117 | spin_lock_init(&newtbl->hashwlock[i]); |
| 118 | spin_lock_init(&newtbl->gates_lock); |
| 119 | |
| 120 | return newtbl; |
| 121 | } |
| 122 | |
| 123 | static void __mesh_table_free(struct mesh_table *tbl) |
| 124 | { |
| 125 | kfree(tbl->hash_buckets); |
| 126 | kfree(tbl->hashwlock); |
| 127 | kfree(tbl); |
| 128 | } |
| 129 | |
| 130 | static void mesh_table_free(struct mesh_table *tbl, bool free_leafs) |
| 131 | { |
| 132 | struct hlist_head *mesh_hash; |
| 133 | struct hlist_node *p, *q; |
| 134 | struct mpath_node *gate; |
| 135 | int i; |
| 136 | |
| 137 | mesh_hash = tbl->hash_buckets; |
| 138 | for (i = 0; i <= tbl->hash_mask; i++) { |
| 139 | spin_lock_bh(&tbl->hashwlock[i]); |
| 140 | hlist_for_each_safe(p, q, &mesh_hash[i]) { |
| 141 | tbl->free_node(p, free_leafs); |
| 142 | atomic_dec(&tbl->entries); |
| 143 | } |
| 144 | spin_unlock_bh(&tbl->hashwlock[i]); |
| 145 | } |
| 146 | if (free_leafs) { |
| 147 | spin_lock_bh(&tbl->gates_lock); |
| 148 | hlist_for_each_entry_safe(gate, q, |
| 149 | tbl->known_gates, list) { |
| 150 | hlist_del(&gate->list); |
| 151 | kfree(gate); |
| 152 | } |
| 153 | kfree(tbl->known_gates); |
| 154 | spin_unlock_bh(&tbl->gates_lock); |
| 155 | } |
| 156 | |
| 157 | __mesh_table_free(tbl); |
| 158 | } |
| 159 | |
| 160 | static int mesh_table_grow(struct mesh_table *oldtbl, |
| 161 | struct mesh_table *newtbl) |
| 162 | { |
| 163 | struct hlist_head *oldhash; |
| 164 | struct hlist_node *p, *q; |
| 165 | int i; |
| 166 | |
| 167 | if (atomic_read(&oldtbl->entries) |
| 168 | < MEAN_CHAIN_LEN * (oldtbl->hash_mask + 1)) |
| 169 | return -EAGAIN; |
| 170 | |
| 171 | newtbl->free_node = oldtbl->free_node; |
| 172 | newtbl->copy_node = oldtbl->copy_node; |
| 173 | newtbl->known_gates = oldtbl->known_gates; |
| 174 | atomic_set(&newtbl->entries, atomic_read(&oldtbl->entries)); |
| 175 | |
| 176 | oldhash = oldtbl->hash_buckets; |
| 177 | for (i = 0; i <= oldtbl->hash_mask; i++) |
| 178 | hlist_for_each(p, &oldhash[i]) |
| 179 | if (oldtbl->copy_node(p, newtbl) < 0) |
| 180 | goto errcopy; |
| 181 | |
| 182 | return 0; |
| 183 | |
| 184 | errcopy: |
| 185 | for (i = 0; i <= newtbl->hash_mask; i++) { |
| 186 | hlist_for_each_safe(p, q, &newtbl->hash_buckets[i]) |
| 187 | oldtbl->free_node(p, 0); |
| 188 | } |
| 189 | return -ENOMEM; |
| 190 | } |
| 191 | |
| 192 | static u32 mesh_table_hash(const u8 *addr, struct ieee80211_sub_if_data *sdata, |
| 193 | struct mesh_table *tbl) |
| 194 | { |
| 195 | /* Use last four bytes of hw addr and interface index as hash index */ |
| 196 | return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex, |
| 197 | tbl->hash_rnd) & tbl->hash_mask; |
| 198 | } |
| 199 | |
| 200 | |
| 201 | /** |
| 202 | * |
| 203 | * mesh_path_assign_nexthop - update mesh path next hop |
| 204 | * |
| 205 | * @mpath: mesh path to update |
| 206 | * @sta: next hop to assign |
| 207 | * |
| 208 | * Locking: mpath->state_lock must be held when calling this function |
| 209 | */ |
| 210 | void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta) |
| 211 | { |
| 212 | struct sk_buff *skb; |
| 213 | struct ieee80211_hdr *hdr; |
| 214 | unsigned long flags; |
| 215 | |
| 216 | rcu_assign_pointer(mpath->next_hop, sta); |
| 217 | |
| 218 | spin_lock_irqsave(&mpath->frame_queue.lock, flags); |
| 219 | skb_queue_walk(&mpath->frame_queue, skb) { |
| 220 | hdr = (struct ieee80211_hdr *) skb->data; |
| 221 | memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN); |
| 222 | memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN); |
| 223 | ieee80211_mps_set_frame_flags(sta->sdata, sta, hdr); |
| 224 | } |
| 225 | |
| 226 | spin_unlock_irqrestore(&mpath->frame_queue.lock, flags); |
| 227 | } |
| 228 | |
| 229 | static void prepare_for_gate(struct sk_buff *skb, char *dst_addr, |
| 230 | struct mesh_path *gate_mpath) |
| 231 | { |
| 232 | struct ieee80211_hdr *hdr; |
| 233 | struct ieee80211s_hdr *mshdr; |
| 234 | int mesh_hdrlen, hdrlen; |
| 235 | char *next_hop; |
| 236 | |
| 237 | hdr = (struct ieee80211_hdr *) skb->data; |
| 238 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| 239 | mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); |
| 240 | |
| 241 | if (!(mshdr->flags & MESH_FLAGS_AE)) { |
| 242 | /* size of the fixed part of the mesh header */ |
| 243 | mesh_hdrlen = 6; |
| 244 | |
| 245 | /* make room for the two extended addresses */ |
| 246 | skb_push(skb, 2 * ETH_ALEN); |
| 247 | memmove(skb->data, hdr, hdrlen + mesh_hdrlen); |
| 248 | |
| 249 | hdr = (struct ieee80211_hdr *) skb->data; |
| 250 | |
| 251 | /* we preserve the previous mesh header and only add |
| 252 | * the new addreses */ |
| 253 | mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); |
| 254 | mshdr->flags = MESH_FLAGS_AE_A5_A6; |
| 255 | memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN); |
| 256 | memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN); |
| 257 | } |
| 258 | |
| 259 | /* update next hop */ |
| 260 | hdr = (struct ieee80211_hdr *) skb->data; |
| 261 | rcu_read_lock(); |
| 262 | next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr; |
| 263 | memcpy(hdr->addr1, next_hop, ETH_ALEN); |
| 264 | rcu_read_unlock(); |
| 265 | memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN); |
| 266 | memcpy(hdr->addr3, dst_addr, ETH_ALEN); |
| 267 | } |
| 268 | |
| 269 | /** |
| 270 | * |
| 271 | * mesh_path_move_to_queue - Move or copy frames from one mpath queue to another |
| 272 | * |
| 273 | * This function is used to transfer or copy frames from an unresolved mpath to |
| 274 | * a gate mpath. The function also adds the Address Extension field and |
| 275 | * updates the next hop. |
| 276 | * |
| 277 | * If a frame already has an Address Extension field, only the next hop and |
| 278 | * destination addresses are updated. |
| 279 | * |
| 280 | * The gate mpath must be an active mpath with a valid mpath->next_hop. |
| 281 | * |
| 282 | * @mpath: An active mpath the frames will be sent to (i.e. the gate) |
| 283 | * @from_mpath: The failed mpath |
| 284 | * @copy: When true, copy all the frames to the new mpath queue. When false, |
| 285 | * move them. |
| 286 | */ |
| 287 | static void mesh_path_move_to_queue(struct mesh_path *gate_mpath, |
| 288 | struct mesh_path *from_mpath, |
| 289 | bool copy) |
| 290 | { |
| 291 | struct sk_buff *skb, *fskb, *tmp; |
| 292 | struct sk_buff_head failq; |
| 293 | unsigned long flags; |
| 294 | |
| 295 | if (WARN_ON(gate_mpath == from_mpath)) |
| 296 | return; |
| 297 | if (WARN_ON(!gate_mpath->next_hop)) |
| 298 | return; |
| 299 | |
| 300 | __skb_queue_head_init(&failq); |
| 301 | |
| 302 | spin_lock_irqsave(&from_mpath->frame_queue.lock, flags); |
| 303 | skb_queue_splice_init(&from_mpath->frame_queue, &failq); |
| 304 | spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags); |
| 305 | |
| 306 | skb_queue_walk_safe(&failq, fskb, tmp) { |
| 307 | if (skb_queue_len(&gate_mpath->frame_queue) >= |
| 308 | MESH_FRAME_QUEUE_LEN) { |
| 309 | mpath_dbg(gate_mpath->sdata, "mpath queue full!\n"); |
| 310 | break; |
| 311 | } |
| 312 | |
| 313 | skb = skb_copy(fskb, GFP_ATOMIC); |
| 314 | if (WARN_ON(!skb)) |
| 315 | break; |
| 316 | |
| 317 | prepare_for_gate(skb, gate_mpath->dst, gate_mpath); |
| 318 | skb_queue_tail(&gate_mpath->frame_queue, skb); |
| 319 | |
| 320 | if (copy) |
| 321 | continue; |
| 322 | |
| 323 | __skb_unlink(fskb, &failq); |
| 324 | kfree_skb(fskb); |
| 325 | } |
| 326 | |
| 327 | mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n", |
| 328 | gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue)); |
| 329 | |
| 330 | if (!copy) |
| 331 | return; |
| 332 | |
| 333 | spin_lock_irqsave(&from_mpath->frame_queue.lock, flags); |
| 334 | skb_queue_splice(&failq, &from_mpath->frame_queue); |
| 335 | spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags); |
| 336 | } |
| 337 | |
| 338 | |
| 339 | static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst, |
| 340 | struct ieee80211_sub_if_data *sdata) |
| 341 | { |
| 342 | struct mesh_path *mpath; |
| 343 | struct hlist_head *bucket; |
| 344 | struct mpath_node *node; |
| 345 | |
| 346 | bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)]; |
| 347 | hlist_for_each_entry_rcu(node, bucket, list) { |
| 348 | mpath = node->mpath; |
| 349 | if (mpath->sdata == sdata && |
| 350 | ether_addr_equal(dst, mpath->dst)) { |
| 351 | if (mpath_expired(mpath)) { |
| 352 | spin_lock_bh(&mpath->state_lock); |
| 353 | mpath->flags &= ~MESH_PATH_ACTIVE; |
| 354 | spin_unlock_bh(&mpath->state_lock); |
| 355 | } |
| 356 | return mpath; |
| 357 | } |
| 358 | } |
| 359 | return NULL; |
| 360 | } |
| 361 | |
| 362 | /** |
| 363 | * mesh_path_lookup - look up a path in the mesh path table |
| 364 | * @sdata: local subif |
| 365 | * @dst: hardware address (ETH_ALEN length) of destination |
| 366 | * |
| 367 | * Returns: pointer to the mesh path structure, or NULL if not found |
| 368 | * |
| 369 | * Locking: must be called within a read rcu section. |
| 370 | */ |
| 371 | struct mesh_path * |
| 372 | mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst) |
| 373 | { |
| 374 | return mpath_lookup(rcu_dereference(mesh_paths), dst, sdata); |
| 375 | } |
| 376 | |
| 377 | struct mesh_path * |
| 378 | mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst) |
| 379 | { |
| 380 | return mpath_lookup(rcu_dereference(mpp_paths), dst, sdata); |
| 381 | } |
| 382 | |
| 383 | |
| 384 | /** |
| 385 | * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index |
| 386 | * @idx: index |
| 387 | * @sdata: local subif, or NULL for all entries |
| 388 | * |
| 389 | * Returns: pointer to the mesh path structure, or NULL if not found. |
| 390 | * |
| 391 | * Locking: must be called within a read rcu section. |
| 392 | */ |
| 393 | struct mesh_path * |
| 394 | mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx) |
| 395 | { |
| 396 | struct mesh_table *tbl = rcu_dereference(mesh_paths); |
| 397 | struct mpath_node *node; |
| 398 | int i; |
| 399 | int j = 0; |
| 400 | |
| 401 | for_each_mesh_entry(tbl, node, i) { |
| 402 | if (sdata && node->mpath->sdata != sdata) |
| 403 | continue; |
| 404 | if (j++ == idx) { |
| 405 | if (mpath_expired(node->mpath)) { |
| 406 | spin_lock_bh(&node->mpath->state_lock); |
| 407 | node->mpath->flags &= ~MESH_PATH_ACTIVE; |
| 408 | spin_unlock_bh(&node->mpath->state_lock); |
| 409 | } |
| 410 | return node->mpath; |
| 411 | } |
| 412 | } |
| 413 | |
| 414 | return NULL; |
| 415 | } |
| 416 | |
| 417 | /** |
| 418 | * mpp_path_lookup_by_idx - look up a path in the proxy path table by its index |
| 419 | * @idx: index |
| 420 | * @sdata: local subif, or NULL for all entries |
| 421 | * |
| 422 | * Returns: pointer to the proxy path structure, or NULL if not found. |
| 423 | * |
| 424 | * Locking: must be called within a read rcu section. |
| 425 | */ |
| 426 | struct mesh_path * |
| 427 | mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx) |
| 428 | { |
| 429 | struct mesh_table *tbl = rcu_dereference(mpp_paths); |
| 430 | struct mpath_node *node; |
| 431 | int i; |
| 432 | int j = 0; |
| 433 | |
| 434 | for_each_mesh_entry(tbl, node, i) { |
| 435 | if (sdata && node->mpath->sdata != sdata) |
| 436 | continue; |
| 437 | if (j++ == idx) |
| 438 | return node->mpath; |
| 439 | } |
| 440 | |
| 441 | return NULL; |
| 442 | } |
| 443 | |
| 444 | /** |
| 445 | * mesh_path_add_gate - add the given mpath to a mesh gate to our path table |
| 446 | * @mpath: gate path to add to table |
| 447 | */ |
| 448 | int mesh_path_add_gate(struct mesh_path *mpath) |
| 449 | { |
| 450 | struct mesh_table *tbl; |
| 451 | struct mpath_node *gate, *new_gate; |
| 452 | int err; |
| 453 | |
| 454 | rcu_read_lock(); |
| 455 | tbl = rcu_dereference(mesh_paths); |
| 456 | |
| 457 | hlist_for_each_entry_rcu(gate, tbl->known_gates, list) |
| 458 | if (gate->mpath == mpath) { |
| 459 | err = -EEXIST; |
| 460 | goto err_rcu; |
| 461 | } |
| 462 | |
| 463 | new_gate = kzalloc(sizeof(struct mpath_node), GFP_ATOMIC); |
| 464 | if (!new_gate) { |
| 465 | err = -ENOMEM; |
| 466 | goto err_rcu; |
| 467 | } |
| 468 | |
| 469 | mpath->is_gate = true; |
| 470 | mpath->sdata->u.mesh.num_gates++; |
| 471 | new_gate->mpath = mpath; |
| 472 | spin_lock_bh(&tbl->gates_lock); |
| 473 | hlist_add_head_rcu(&new_gate->list, tbl->known_gates); |
| 474 | spin_unlock_bh(&tbl->gates_lock); |
| 475 | mpath_dbg(mpath->sdata, |
| 476 | "Mesh path: Recorded new gate: %pM. %d known gates\n", |
| 477 | mpath->dst, mpath->sdata->u.mesh.num_gates); |
| 478 | err = 0; |
| 479 | err_rcu: |
| 480 | rcu_read_unlock(); |
| 481 | return err; |
| 482 | } |
| 483 | |
| 484 | /** |
| 485 | * mesh_gate_del - remove a mesh gate from the list of known gates |
| 486 | * @tbl: table which holds our list of known gates |
| 487 | * @mpath: gate mpath |
| 488 | * |
| 489 | * Locking: must be called inside rcu_read_lock() section |
| 490 | */ |
| 491 | static void mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath) |
| 492 | { |
| 493 | struct mpath_node *gate; |
| 494 | struct hlist_node *q; |
| 495 | |
| 496 | hlist_for_each_entry_safe(gate, q, tbl->known_gates, list) { |
| 497 | if (gate->mpath != mpath) |
| 498 | continue; |
| 499 | spin_lock_bh(&tbl->gates_lock); |
| 500 | hlist_del_rcu(&gate->list); |
| 501 | kfree_rcu(gate, rcu); |
| 502 | spin_unlock_bh(&tbl->gates_lock); |
| 503 | mpath->sdata->u.mesh.num_gates--; |
| 504 | mpath->is_gate = false; |
| 505 | mpath_dbg(mpath->sdata, |
| 506 | "Mesh path: Deleted gate: %pM. %d known gates\n", |
| 507 | mpath->dst, mpath->sdata->u.mesh.num_gates); |
| 508 | break; |
| 509 | } |
| 510 | } |
| 511 | |
| 512 | /** |
| 513 | * mesh_gate_num - number of gates known to this interface |
| 514 | * @sdata: subif data |
| 515 | */ |
| 516 | int mesh_gate_num(struct ieee80211_sub_if_data *sdata) |
| 517 | { |
| 518 | return sdata->u.mesh.num_gates; |
| 519 | } |
| 520 | |
| 521 | /** |
| 522 | * mesh_path_add - allocate and add a new path to the mesh path table |
| 523 | * @dst: destination address of the path (ETH_ALEN length) |
| 524 | * @sdata: local subif |
| 525 | * |
| 526 | * Returns: 0 on success |
| 527 | * |
| 528 | * State: the initial state of the new path is set to 0 |
| 529 | */ |
| 530 | struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata, |
| 531 | const u8 *dst) |
| 532 | { |
| 533 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 534 | struct ieee80211_local *local = sdata->local; |
| 535 | struct mesh_table *tbl; |
| 536 | struct mesh_path *mpath, *new_mpath; |
| 537 | struct mpath_node *node, *new_node; |
| 538 | struct hlist_head *bucket; |
| 539 | int grow = 0; |
| 540 | int err; |
| 541 | u32 hash_idx; |
| 542 | |
| 543 | if (ether_addr_equal(dst, sdata->vif.addr)) |
| 544 | /* never add ourselves as neighbours */ |
| 545 | return ERR_PTR(-ENOTSUPP); |
| 546 | |
| 547 | if (is_multicast_ether_addr(dst)) |
| 548 | return ERR_PTR(-ENOTSUPP); |
| 549 | |
| 550 | if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0) |
| 551 | return ERR_PTR(-ENOSPC); |
| 552 | |
| 553 | read_lock_bh(&pathtbl_resize_lock); |
| 554 | tbl = resize_dereference_mesh_paths(); |
| 555 | |
| 556 | hash_idx = mesh_table_hash(dst, sdata, tbl); |
| 557 | bucket = &tbl->hash_buckets[hash_idx]; |
| 558 | |
| 559 | spin_lock(&tbl->hashwlock[hash_idx]); |
| 560 | |
| 561 | hlist_for_each_entry(node, bucket, list) { |
| 562 | mpath = node->mpath; |
| 563 | if (mpath->sdata == sdata && |
| 564 | ether_addr_equal(dst, mpath->dst)) |
| 565 | goto found; |
| 566 | } |
| 567 | |
| 568 | err = -ENOMEM; |
| 569 | new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC); |
| 570 | if (!new_mpath) |
| 571 | goto err_path_alloc; |
| 572 | |
| 573 | new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC); |
| 574 | if (!new_node) |
| 575 | goto err_node_alloc; |
| 576 | |
| 577 | memcpy(new_mpath->dst, dst, ETH_ALEN); |
| 578 | eth_broadcast_addr(new_mpath->rann_snd_addr); |
| 579 | new_mpath->is_root = false; |
| 580 | new_mpath->sdata = sdata; |
| 581 | new_mpath->flags = 0; |
| 582 | skb_queue_head_init(&new_mpath->frame_queue); |
| 583 | new_node->mpath = new_mpath; |
| 584 | new_mpath->timer.data = (unsigned long) new_mpath; |
| 585 | new_mpath->timer.function = mesh_path_timer; |
| 586 | new_mpath->exp_time = jiffies; |
| 587 | spin_lock_init(&new_mpath->state_lock); |
| 588 | init_timer(&new_mpath->timer); |
| 589 | |
| 590 | hlist_add_head_rcu(&new_node->list, bucket); |
| 591 | if (atomic_inc_return(&tbl->entries) >= |
| 592 | MEAN_CHAIN_LEN * (tbl->hash_mask + 1)) |
| 593 | grow = 1; |
| 594 | |
| 595 | mesh_paths_generation++; |
| 596 | |
| 597 | if (grow) { |
| 598 | set_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags); |
| 599 | ieee80211_queue_work(&local->hw, &sdata->work); |
| 600 | } |
| 601 | mpath = new_mpath; |
| 602 | found: |
| 603 | spin_unlock(&tbl->hashwlock[hash_idx]); |
| 604 | read_unlock_bh(&pathtbl_resize_lock); |
| 605 | return mpath; |
| 606 | |
| 607 | err_node_alloc: |
| 608 | kfree(new_mpath); |
| 609 | err_path_alloc: |
| 610 | atomic_dec(&sdata->u.mesh.mpaths); |
| 611 | spin_unlock(&tbl->hashwlock[hash_idx]); |
| 612 | read_unlock_bh(&pathtbl_resize_lock); |
| 613 | return ERR_PTR(err); |
| 614 | } |
| 615 | |
| 616 | static void mesh_table_free_rcu(struct rcu_head *rcu) |
| 617 | { |
| 618 | struct mesh_table *tbl = container_of(rcu, struct mesh_table, rcu_head); |
| 619 | |
| 620 | mesh_table_free(tbl, false); |
| 621 | } |
| 622 | |
| 623 | void mesh_mpath_table_grow(void) |
| 624 | { |
| 625 | struct mesh_table *oldtbl, *newtbl; |
| 626 | |
| 627 | write_lock_bh(&pathtbl_resize_lock); |
| 628 | oldtbl = resize_dereference_mesh_paths(); |
| 629 | newtbl = mesh_table_alloc(oldtbl->size_order + 1); |
| 630 | if (!newtbl) |
| 631 | goto out; |
| 632 | if (mesh_table_grow(oldtbl, newtbl) < 0) { |
| 633 | __mesh_table_free(newtbl); |
| 634 | goto out; |
| 635 | } |
| 636 | rcu_assign_pointer(mesh_paths, newtbl); |
| 637 | |
| 638 | call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu); |
| 639 | |
| 640 | out: |
| 641 | write_unlock_bh(&pathtbl_resize_lock); |
| 642 | } |
| 643 | |
| 644 | void mesh_mpp_table_grow(void) |
| 645 | { |
| 646 | struct mesh_table *oldtbl, *newtbl; |
| 647 | |
| 648 | write_lock_bh(&pathtbl_resize_lock); |
| 649 | oldtbl = resize_dereference_mpp_paths(); |
| 650 | newtbl = mesh_table_alloc(oldtbl->size_order + 1); |
| 651 | if (!newtbl) |
| 652 | goto out; |
| 653 | if (mesh_table_grow(oldtbl, newtbl) < 0) { |
| 654 | __mesh_table_free(newtbl); |
| 655 | goto out; |
| 656 | } |
| 657 | rcu_assign_pointer(mpp_paths, newtbl); |
| 658 | call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu); |
| 659 | |
| 660 | out: |
| 661 | write_unlock_bh(&pathtbl_resize_lock); |
| 662 | } |
| 663 | |
| 664 | int mpp_path_add(struct ieee80211_sub_if_data *sdata, |
| 665 | const u8 *dst, const u8 *mpp) |
| 666 | { |
| 667 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 668 | struct ieee80211_local *local = sdata->local; |
| 669 | struct mesh_table *tbl; |
| 670 | struct mesh_path *mpath, *new_mpath; |
| 671 | struct mpath_node *node, *new_node; |
| 672 | struct hlist_head *bucket; |
| 673 | int grow = 0; |
| 674 | int err = 0; |
| 675 | u32 hash_idx; |
| 676 | |
| 677 | if (ether_addr_equal(dst, sdata->vif.addr)) |
| 678 | /* never add ourselves as neighbours */ |
| 679 | return -ENOTSUPP; |
| 680 | |
| 681 | if (is_multicast_ether_addr(dst)) |
| 682 | return -ENOTSUPP; |
| 683 | |
| 684 | err = -ENOMEM; |
| 685 | new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC); |
| 686 | if (!new_mpath) |
| 687 | goto err_path_alloc; |
| 688 | |
| 689 | new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC); |
| 690 | if (!new_node) |
| 691 | goto err_node_alloc; |
| 692 | |
| 693 | read_lock_bh(&pathtbl_resize_lock); |
| 694 | memcpy(new_mpath->dst, dst, ETH_ALEN); |
| 695 | memcpy(new_mpath->mpp, mpp, ETH_ALEN); |
| 696 | new_mpath->sdata = sdata; |
| 697 | new_mpath->flags = 0; |
| 698 | skb_queue_head_init(&new_mpath->frame_queue); |
| 699 | new_node->mpath = new_mpath; |
| 700 | init_timer(&new_mpath->timer); |
| 701 | new_mpath->exp_time = jiffies; |
| 702 | spin_lock_init(&new_mpath->state_lock); |
| 703 | |
| 704 | tbl = resize_dereference_mpp_paths(); |
| 705 | |
| 706 | hash_idx = mesh_table_hash(dst, sdata, tbl); |
| 707 | bucket = &tbl->hash_buckets[hash_idx]; |
| 708 | |
| 709 | spin_lock(&tbl->hashwlock[hash_idx]); |
| 710 | |
| 711 | err = -EEXIST; |
| 712 | hlist_for_each_entry(node, bucket, list) { |
| 713 | mpath = node->mpath; |
| 714 | if (mpath->sdata == sdata && |
| 715 | ether_addr_equal(dst, mpath->dst)) |
| 716 | goto err_exists; |
| 717 | } |
| 718 | |
| 719 | hlist_add_head_rcu(&new_node->list, bucket); |
| 720 | if (atomic_inc_return(&tbl->entries) >= |
| 721 | MEAN_CHAIN_LEN * (tbl->hash_mask + 1)) |
| 722 | grow = 1; |
| 723 | |
| 724 | spin_unlock(&tbl->hashwlock[hash_idx]); |
| 725 | read_unlock_bh(&pathtbl_resize_lock); |
| 726 | |
| 727 | mpp_paths_generation++; |
| 728 | |
| 729 | if (grow) { |
| 730 | set_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags); |
| 731 | ieee80211_queue_work(&local->hw, &sdata->work); |
| 732 | } |
| 733 | return 0; |
| 734 | |
| 735 | err_exists: |
| 736 | spin_unlock(&tbl->hashwlock[hash_idx]); |
| 737 | read_unlock_bh(&pathtbl_resize_lock); |
| 738 | kfree(new_node); |
| 739 | err_node_alloc: |
| 740 | kfree(new_mpath); |
| 741 | err_path_alloc: |
| 742 | return err; |
| 743 | } |
| 744 | |
| 745 | |
| 746 | /** |
| 747 | * mesh_plink_broken - deactivates paths and sends perr when a link breaks |
| 748 | * |
| 749 | * @sta: broken peer link |
| 750 | * |
| 751 | * This function must be called from the rate control algorithm if enough |
| 752 | * delivery errors suggest that a peer link is no longer usable. |
| 753 | */ |
| 754 | void mesh_plink_broken(struct sta_info *sta) |
| 755 | { |
| 756 | struct mesh_table *tbl; |
| 757 | static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; |
| 758 | struct mesh_path *mpath; |
| 759 | struct mpath_node *node; |
| 760 | struct ieee80211_sub_if_data *sdata = sta->sdata; |
| 761 | int i; |
| 762 | |
| 763 | rcu_read_lock(); |
| 764 | tbl = rcu_dereference(mesh_paths); |
| 765 | for_each_mesh_entry(tbl, node, i) { |
| 766 | mpath = node->mpath; |
| 767 | if (rcu_access_pointer(mpath->next_hop) == sta && |
| 768 | mpath->flags & MESH_PATH_ACTIVE && |
| 769 | !(mpath->flags & MESH_PATH_FIXED)) { |
| 770 | spin_lock_bh(&mpath->state_lock); |
| 771 | mpath->flags &= ~MESH_PATH_ACTIVE; |
| 772 | ++mpath->sn; |
| 773 | spin_unlock_bh(&mpath->state_lock); |
| 774 | mesh_path_error_tx(sdata, |
| 775 | sdata->u.mesh.mshcfg.element_ttl, |
| 776 | mpath->dst, mpath->sn, |
| 777 | WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, bcast); |
| 778 | } |
| 779 | } |
| 780 | rcu_read_unlock(); |
| 781 | } |
| 782 | |
| 783 | static void mesh_path_node_reclaim(struct rcu_head *rp) |
| 784 | { |
| 785 | struct mpath_node *node = container_of(rp, struct mpath_node, rcu); |
| 786 | |
| 787 | del_timer_sync(&node->mpath->timer); |
| 788 | kfree(node->mpath); |
| 789 | kfree(node); |
| 790 | } |
| 791 | |
| 792 | /* needs to be called with the corresponding hashwlock taken */ |
| 793 | static void __mesh_path_del(struct mesh_table *tbl, struct mpath_node *node) |
| 794 | { |
| 795 | struct mesh_path *mpath = node->mpath; |
| 796 | struct ieee80211_sub_if_data *sdata = node->mpath->sdata; |
| 797 | |
| 798 | spin_lock(&mpath->state_lock); |
| 799 | mpath->flags |= MESH_PATH_RESOLVING; |
| 800 | if (mpath->is_gate) |
| 801 | mesh_gate_del(tbl, mpath); |
| 802 | hlist_del_rcu(&node->list); |
| 803 | call_rcu(&node->rcu, mesh_path_node_reclaim); |
| 804 | spin_unlock(&mpath->state_lock); |
| 805 | atomic_dec(&sdata->u.mesh.mpaths); |
| 806 | atomic_dec(&tbl->entries); |
| 807 | } |
| 808 | |
| 809 | /** |
| 810 | * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches |
| 811 | * |
| 812 | * @sta: mesh peer to match |
| 813 | * |
| 814 | * RCU notes: this function is called when a mesh plink transitions from |
| 815 | * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that |
| 816 | * allows path creation. This will happen before the sta can be freed (because |
| 817 | * sta_info_destroy() calls this) so any reader in a rcu read block will be |
| 818 | * protected against the plink disappearing. |
| 819 | */ |
| 820 | void mesh_path_flush_by_nexthop(struct sta_info *sta) |
| 821 | { |
| 822 | struct mesh_table *tbl; |
| 823 | struct mesh_path *mpath; |
| 824 | struct mpath_node *node; |
| 825 | int i; |
| 826 | |
| 827 | rcu_read_lock(); |
| 828 | read_lock_bh(&pathtbl_resize_lock); |
| 829 | tbl = resize_dereference_mesh_paths(); |
| 830 | for_each_mesh_entry(tbl, node, i) { |
| 831 | mpath = node->mpath; |
| 832 | if (rcu_access_pointer(mpath->next_hop) == sta) { |
| 833 | spin_lock(&tbl->hashwlock[i]); |
| 834 | __mesh_path_del(tbl, node); |
| 835 | spin_unlock(&tbl->hashwlock[i]); |
| 836 | } |
| 837 | } |
| 838 | read_unlock_bh(&pathtbl_resize_lock); |
| 839 | rcu_read_unlock(); |
| 840 | } |
| 841 | |
| 842 | static void mpp_flush_by_proxy(struct ieee80211_sub_if_data *sdata, |
| 843 | const u8 *proxy) |
| 844 | { |
| 845 | struct mesh_table *tbl; |
| 846 | struct mesh_path *mpp; |
| 847 | struct mpath_node *node; |
| 848 | int i; |
| 849 | |
| 850 | rcu_read_lock(); |
| 851 | read_lock_bh(&pathtbl_resize_lock); |
| 852 | tbl = resize_dereference_mpp_paths(); |
| 853 | for_each_mesh_entry(tbl, node, i) { |
| 854 | mpp = node->mpath; |
| 855 | if (ether_addr_equal(mpp->mpp, proxy)) { |
| 856 | spin_lock(&tbl->hashwlock[i]); |
| 857 | __mesh_path_del(tbl, node); |
| 858 | spin_unlock(&tbl->hashwlock[i]); |
| 859 | } |
| 860 | } |
| 861 | read_unlock_bh(&pathtbl_resize_lock); |
| 862 | rcu_read_unlock(); |
| 863 | } |
| 864 | |
| 865 | static void table_flush_by_iface(struct mesh_table *tbl, |
| 866 | struct ieee80211_sub_if_data *sdata) |
| 867 | { |
| 868 | struct mesh_path *mpath; |
| 869 | struct mpath_node *node; |
| 870 | int i; |
| 871 | |
| 872 | WARN_ON(!rcu_read_lock_held()); |
| 873 | for_each_mesh_entry(tbl, node, i) { |
| 874 | mpath = node->mpath; |
| 875 | if (mpath->sdata != sdata) |
| 876 | continue; |
| 877 | spin_lock_bh(&tbl->hashwlock[i]); |
| 878 | __mesh_path_del(tbl, node); |
| 879 | spin_unlock_bh(&tbl->hashwlock[i]); |
| 880 | } |
| 881 | } |
| 882 | |
| 883 | /** |
| 884 | * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface |
| 885 | * |
| 886 | * This function deletes both mesh paths as well as mesh portal paths. |
| 887 | * |
| 888 | * @sdata: interface data to match |
| 889 | * |
| 890 | */ |
| 891 | void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata) |
| 892 | { |
| 893 | struct mesh_table *tbl; |
| 894 | |
| 895 | rcu_read_lock(); |
| 896 | read_lock_bh(&pathtbl_resize_lock); |
| 897 | tbl = resize_dereference_mesh_paths(); |
| 898 | table_flush_by_iface(tbl, sdata); |
| 899 | tbl = resize_dereference_mpp_paths(); |
| 900 | table_flush_by_iface(tbl, sdata); |
| 901 | read_unlock_bh(&pathtbl_resize_lock); |
| 902 | rcu_read_unlock(); |
| 903 | } |
| 904 | |
| 905 | /** |
| 906 | * table_path_del - delete a path from the mesh or mpp table |
| 907 | * |
| 908 | * @tbl: mesh or mpp path table |
| 909 | * @sdata: local subif |
| 910 | * @addr: dst address (ETH_ALEN length) |
| 911 | * |
| 912 | * Returns: 0 if successful |
| 913 | */ |
| 914 | static int table_path_del(struct mesh_table __rcu *rcu_tbl, |
| 915 | struct ieee80211_sub_if_data *sdata, |
| 916 | const u8 *addr) |
| 917 | { |
| 918 | struct mesh_table *tbl; |
| 919 | struct mesh_path *mpath; |
| 920 | struct mpath_node *node; |
| 921 | struct hlist_head *bucket; |
| 922 | int hash_idx; |
| 923 | int err = 0; |
| 924 | |
| 925 | tbl = resize_dereference_paths(rcu_tbl); |
| 926 | hash_idx = mesh_table_hash(addr, sdata, tbl); |
| 927 | bucket = &tbl->hash_buckets[hash_idx]; |
| 928 | |
| 929 | spin_lock(&tbl->hashwlock[hash_idx]); |
| 930 | hlist_for_each_entry(node, bucket, list) { |
| 931 | mpath = node->mpath; |
| 932 | if (mpath->sdata == sdata && |
| 933 | ether_addr_equal(addr, mpath->dst)) { |
| 934 | __mesh_path_del(tbl, node); |
| 935 | goto enddel; |
| 936 | } |
| 937 | } |
| 938 | |
| 939 | err = -ENXIO; |
| 940 | enddel: |
| 941 | spin_unlock(&tbl->hashwlock[hash_idx]); |
| 942 | return err; |
| 943 | } |
| 944 | |
| 945 | /** |
| 946 | * mesh_path_del - delete a mesh path from the table |
| 947 | * |
| 948 | * @addr: dst address (ETH_ALEN length) |
| 949 | * @sdata: local subif |
| 950 | * |
| 951 | * Returns: 0 if successful |
| 952 | */ |
| 953 | int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr) |
| 954 | { |
| 955 | int err = 0; |
| 956 | |
| 957 | /* flush relevant mpp entries first */ |
| 958 | mpp_flush_by_proxy(sdata, addr); |
| 959 | |
| 960 | read_lock_bh(&pathtbl_resize_lock); |
| 961 | err = table_path_del(mesh_paths, sdata, addr); |
| 962 | mesh_paths_generation++; |
| 963 | read_unlock_bh(&pathtbl_resize_lock); |
| 964 | |
| 965 | return err; |
| 966 | } |
| 967 | |
| 968 | /** |
| 969 | * mpp_path_del - delete a mesh proxy path from the table |
| 970 | * |
| 971 | * @addr: addr address (ETH_ALEN length) |
| 972 | * @sdata: local subif |
| 973 | * |
| 974 | * Returns: 0 if successful |
| 975 | */ |
| 976 | static int mpp_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr) |
| 977 | { |
| 978 | int err = 0; |
| 979 | |
| 980 | read_lock_bh(&pathtbl_resize_lock); |
| 981 | err = table_path_del(mpp_paths, sdata, addr); |
| 982 | mpp_paths_generation++; |
| 983 | read_unlock_bh(&pathtbl_resize_lock); |
| 984 | |
| 985 | return err; |
| 986 | } |
| 987 | |
| 988 | /** |
| 989 | * mesh_path_tx_pending - sends pending frames in a mesh path queue |
| 990 | * |
| 991 | * @mpath: mesh path to activate |
| 992 | * |
| 993 | * Locking: the state_lock of the mpath structure must NOT be held when calling |
| 994 | * this function. |
| 995 | */ |
| 996 | void mesh_path_tx_pending(struct mesh_path *mpath) |
| 997 | { |
| 998 | if (mpath->flags & MESH_PATH_ACTIVE) |
| 999 | ieee80211_add_pending_skbs(mpath->sdata->local, |
| 1000 | &mpath->frame_queue); |
| 1001 | } |
| 1002 | |
| 1003 | /** |
| 1004 | * mesh_path_send_to_gates - sends pending frames to all known mesh gates |
| 1005 | * |
| 1006 | * @mpath: mesh path whose queue will be emptied |
| 1007 | * |
| 1008 | * If there is only one gate, the frames are transferred from the failed mpath |
| 1009 | * queue to that gate's queue. If there are more than one gates, the frames |
| 1010 | * are copied from each gate to the next. After frames are copied, the |
| 1011 | * mpath queues are emptied onto the transmission queue. |
| 1012 | */ |
| 1013 | int mesh_path_send_to_gates(struct mesh_path *mpath) |
| 1014 | { |
| 1015 | struct ieee80211_sub_if_data *sdata = mpath->sdata; |
| 1016 | struct mesh_table *tbl; |
| 1017 | struct mesh_path *from_mpath = mpath; |
| 1018 | struct mpath_node *gate = NULL; |
| 1019 | bool copy = false; |
| 1020 | struct hlist_head *known_gates; |
| 1021 | |
| 1022 | rcu_read_lock(); |
| 1023 | tbl = rcu_dereference(mesh_paths); |
| 1024 | known_gates = tbl->known_gates; |
| 1025 | rcu_read_unlock(); |
| 1026 | |
| 1027 | if (!known_gates) |
| 1028 | return -EHOSTUNREACH; |
| 1029 | |
| 1030 | hlist_for_each_entry_rcu(gate, known_gates, list) { |
| 1031 | if (gate->mpath->sdata != sdata) |
| 1032 | continue; |
| 1033 | |
| 1034 | if (gate->mpath->flags & MESH_PATH_ACTIVE) { |
| 1035 | mpath_dbg(sdata, "Forwarding to %pM\n", gate->mpath->dst); |
| 1036 | mesh_path_move_to_queue(gate->mpath, from_mpath, copy); |
| 1037 | from_mpath = gate->mpath; |
| 1038 | copy = true; |
| 1039 | } else { |
| 1040 | mpath_dbg(sdata, |
| 1041 | "Not forwarding to %pM (flags %#x)\n", |
| 1042 | gate->mpath->dst, gate->mpath->flags); |
| 1043 | } |
| 1044 | } |
| 1045 | |
| 1046 | hlist_for_each_entry_rcu(gate, known_gates, list) |
| 1047 | if (gate->mpath->sdata == sdata) { |
| 1048 | mpath_dbg(sdata, "Sending to %pM\n", gate->mpath->dst); |
| 1049 | mesh_path_tx_pending(gate->mpath); |
| 1050 | } |
| 1051 | |
| 1052 | return (from_mpath == mpath) ? -EHOSTUNREACH : 0; |
| 1053 | } |
| 1054 | |
| 1055 | /** |
| 1056 | * mesh_path_discard_frame - discard a frame whose path could not be resolved |
| 1057 | * |
| 1058 | * @skb: frame to discard |
| 1059 | * @sdata: network subif the frame was to be sent through |
| 1060 | * |
| 1061 | * Locking: the function must me called within a rcu_read_lock region |
| 1062 | */ |
| 1063 | void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata, |
| 1064 | struct sk_buff *skb) |
| 1065 | { |
| 1066 | kfree_skb(skb); |
| 1067 | sdata->u.mesh.mshstats.dropped_frames_no_route++; |
| 1068 | } |
| 1069 | |
| 1070 | /** |
| 1071 | * mesh_path_flush_pending - free the pending queue of a mesh path |
| 1072 | * |
| 1073 | * @mpath: mesh path whose queue has to be freed |
| 1074 | * |
| 1075 | * Locking: the function must me called within a rcu_read_lock region |
| 1076 | */ |
| 1077 | void mesh_path_flush_pending(struct mesh_path *mpath) |
| 1078 | { |
| 1079 | struct sk_buff *skb; |
| 1080 | |
| 1081 | while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL) |
| 1082 | mesh_path_discard_frame(mpath->sdata, skb); |
| 1083 | } |
| 1084 | |
| 1085 | /** |
| 1086 | * mesh_path_fix_nexthop - force a specific next hop for a mesh path |
| 1087 | * |
| 1088 | * @mpath: the mesh path to modify |
| 1089 | * @next_hop: the next hop to force |
| 1090 | * |
| 1091 | * Locking: this function must be called holding mpath->state_lock |
| 1092 | */ |
| 1093 | void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop) |
| 1094 | { |
| 1095 | spin_lock_bh(&mpath->state_lock); |
| 1096 | mesh_path_assign_nexthop(mpath, next_hop); |
| 1097 | mpath->sn = 0xffff; |
| 1098 | mpath->metric = 0; |
| 1099 | mpath->hop_count = 0; |
| 1100 | mpath->exp_time = 0; |
| 1101 | mpath->flags |= MESH_PATH_FIXED; |
| 1102 | mesh_path_activate(mpath); |
| 1103 | spin_unlock_bh(&mpath->state_lock); |
| 1104 | mesh_path_tx_pending(mpath); |
| 1105 | } |
| 1106 | |
| 1107 | static void mesh_path_node_free(struct hlist_node *p, bool free_leafs) |
| 1108 | { |
| 1109 | struct mesh_path *mpath; |
| 1110 | struct mpath_node *node = hlist_entry(p, struct mpath_node, list); |
| 1111 | mpath = node->mpath; |
| 1112 | hlist_del_rcu(p); |
| 1113 | if (free_leafs) { |
| 1114 | del_timer_sync(&mpath->timer); |
| 1115 | kfree(mpath); |
| 1116 | } |
| 1117 | kfree(node); |
| 1118 | } |
| 1119 | |
| 1120 | static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl) |
| 1121 | { |
| 1122 | struct mesh_path *mpath; |
| 1123 | struct mpath_node *node, *new_node; |
| 1124 | u32 hash_idx; |
| 1125 | |
| 1126 | new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC); |
| 1127 | if (new_node == NULL) |
| 1128 | return -ENOMEM; |
| 1129 | |
| 1130 | node = hlist_entry(p, struct mpath_node, list); |
| 1131 | mpath = node->mpath; |
| 1132 | new_node->mpath = mpath; |
| 1133 | hash_idx = mesh_table_hash(mpath->dst, mpath->sdata, newtbl); |
| 1134 | hlist_add_head(&new_node->list, |
| 1135 | &newtbl->hash_buckets[hash_idx]); |
| 1136 | return 0; |
| 1137 | } |
| 1138 | |
| 1139 | int mesh_pathtbl_init(void) |
| 1140 | { |
| 1141 | struct mesh_table *tbl_path, *tbl_mpp; |
| 1142 | int ret; |
| 1143 | |
| 1144 | tbl_path = mesh_table_alloc(INIT_PATHS_SIZE_ORDER); |
| 1145 | if (!tbl_path) |
| 1146 | return -ENOMEM; |
| 1147 | tbl_path->free_node = &mesh_path_node_free; |
| 1148 | tbl_path->copy_node = &mesh_path_node_copy; |
| 1149 | tbl_path->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC); |
| 1150 | if (!tbl_path->known_gates) { |
| 1151 | ret = -ENOMEM; |
| 1152 | goto free_path; |
| 1153 | } |
| 1154 | INIT_HLIST_HEAD(tbl_path->known_gates); |
| 1155 | |
| 1156 | |
| 1157 | tbl_mpp = mesh_table_alloc(INIT_PATHS_SIZE_ORDER); |
| 1158 | if (!tbl_mpp) { |
| 1159 | ret = -ENOMEM; |
| 1160 | goto free_path; |
| 1161 | } |
| 1162 | tbl_mpp->free_node = &mesh_path_node_free; |
| 1163 | tbl_mpp->copy_node = &mesh_path_node_copy; |
| 1164 | tbl_mpp->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC); |
| 1165 | if (!tbl_mpp->known_gates) { |
| 1166 | ret = -ENOMEM; |
| 1167 | goto free_mpp; |
| 1168 | } |
| 1169 | INIT_HLIST_HEAD(tbl_mpp->known_gates); |
| 1170 | |
| 1171 | /* Need no locking since this is during init */ |
| 1172 | RCU_INIT_POINTER(mesh_paths, tbl_path); |
| 1173 | RCU_INIT_POINTER(mpp_paths, tbl_mpp); |
| 1174 | |
| 1175 | return 0; |
| 1176 | |
| 1177 | free_mpp: |
| 1178 | mesh_table_free(tbl_mpp, true); |
| 1179 | free_path: |
| 1180 | mesh_table_free(tbl_path, true); |
| 1181 | return ret; |
| 1182 | } |
| 1183 | |
| 1184 | void mesh_path_expire(struct ieee80211_sub_if_data *sdata) |
| 1185 | { |
| 1186 | struct mesh_table *tbl; |
| 1187 | struct mesh_path *mpath; |
| 1188 | struct mpath_node *node; |
| 1189 | int i; |
| 1190 | |
| 1191 | rcu_read_lock(); |
| 1192 | tbl = rcu_dereference(mesh_paths); |
| 1193 | for_each_mesh_entry(tbl, node, i) { |
| 1194 | if (node->mpath->sdata != sdata) |
| 1195 | continue; |
| 1196 | mpath = node->mpath; |
| 1197 | if ((!(mpath->flags & MESH_PATH_RESOLVING)) && |
| 1198 | (!(mpath->flags & MESH_PATH_FIXED)) && |
| 1199 | time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE)) |
| 1200 | mesh_path_del(mpath->sdata, mpath->dst); |
| 1201 | } |
| 1202 | |
| 1203 | tbl = rcu_dereference(mpp_paths); |
| 1204 | for_each_mesh_entry(tbl, node, i) { |
| 1205 | if (node->mpath->sdata != sdata) |
| 1206 | continue; |
| 1207 | mpath = node->mpath; |
| 1208 | if ((!(mpath->flags & MESH_PATH_FIXED)) && |
| 1209 | time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE)) |
| 1210 | mpp_path_del(mpath->sdata, mpath->dst); |
| 1211 | } |
| 1212 | |
| 1213 | rcu_read_unlock(); |
| 1214 | } |
| 1215 | |
| 1216 | void mesh_pathtbl_unregister(void) |
| 1217 | { |
| 1218 | /* no need for locking during exit path */ |
| 1219 | mesh_table_free(rcu_dereference_protected(mesh_paths, 1), true); |
| 1220 | mesh_table_free(rcu_dereference_protected(mpp_paths, 1), true); |
| 1221 | } |