2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
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.
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>
18 #include "ieee80211_i.h"
21 /* There will be initially 2^INIT_PATHS_SIZE_ORDER buckets */
22 #define INIT_PATHS_SIZE_ORDER 2
24 /* Keep the mean chain length below this constant */
25 #define MEAN_CHAIN_LEN 2
27 #define MPATH_EXPIRED(mpath) ((mpath->flags & MESH_PATH_ACTIVE) && \
28 time_after(jiffies, mpath->exp_time) && \
29 !(mpath->flags & MESH_PATH_FIXED))
32 struct hlist_node list;
34 /* This indirection allows two different tables to point to the same
35 * mesh_path structure, useful when resizing
37 struct mesh_path *mpath;
40 static struct mesh_table __rcu *mesh_paths;
41 static struct mesh_table __rcu *mpp_paths; /* Store paths for MPP&MAP */
43 int mesh_paths_generation;
45 /* This lock will have the grow table function as writer and add / delete nodes
46 * as readers. RCU provides sufficient protection only when reading the table
47 * (i.e. doing lookups). Adding or adding or removing nodes requires we take
48 * the read lock or we risk operating on an old table. The write lock is only
49 * needed when modifying the number of buckets a table.
51 static DEFINE_RWLOCK(pathtbl_resize_lock);
54 static inline struct mesh_table *resize_dereference_mesh_paths(void)
56 return rcu_dereference_protected(mesh_paths,
57 lockdep_is_held(&pathtbl_resize_lock));
60 static inline struct mesh_table *resize_dereference_mpp_paths(void)
62 return rcu_dereference_protected(mpp_paths,
63 lockdep_is_held(&pathtbl_resize_lock));
67 * CAREFUL -- "tbl" must not be an expression,
68 * in particular not an rcu_dereference(), since
69 * it's used twice. So it is illegal to do
70 * for_each_mesh_entry(rcu_dereference(...), ...)
72 #define for_each_mesh_entry(tbl, p, node, i) \
73 for (i = 0; i <= tbl->hash_mask; i++) \
74 hlist_for_each_entry_rcu(node, p, &tbl->hash_buckets[i], list)
77 static struct mesh_table *mesh_table_alloc(int size_order)
80 struct mesh_table *newtbl;
82 newtbl = kmalloc(sizeof(struct mesh_table), GFP_ATOMIC);
86 newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
87 (1 << size_order), GFP_ATOMIC);
89 if (!newtbl->hash_buckets) {
94 newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
95 (1 << size_order), GFP_ATOMIC);
96 if (!newtbl->hashwlock) {
97 kfree(newtbl->hash_buckets);
102 newtbl->size_order = size_order;
103 newtbl->hash_mask = (1 << size_order) - 1;
104 atomic_set(&newtbl->entries, 0);
105 get_random_bytes(&newtbl->hash_rnd,
106 sizeof(newtbl->hash_rnd));
107 for (i = 0; i <= newtbl->hash_mask; i++)
108 spin_lock_init(&newtbl->hashwlock[i]);
109 spin_lock_init(&newtbl->gates_lock);
114 static void __mesh_table_free(struct mesh_table *tbl)
116 kfree(tbl->hash_buckets);
117 kfree(tbl->hashwlock);
121 static void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
123 struct hlist_head *mesh_hash;
124 struct hlist_node *p, *q;
125 struct mpath_node *gate;
128 mesh_hash = tbl->hash_buckets;
129 for (i = 0; i <= tbl->hash_mask; i++) {
130 spin_lock_bh(&tbl->hashwlock[i]);
131 hlist_for_each_safe(p, q, &mesh_hash[i]) {
132 tbl->free_node(p, free_leafs);
133 atomic_dec(&tbl->entries);
135 spin_unlock_bh(&tbl->hashwlock[i]);
138 spin_lock_bh(&tbl->gates_lock);
139 hlist_for_each_entry_safe(gate, p, q,
140 tbl->known_gates, list) {
141 hlist_del(&gate->list);
144 kfree(tbl->known_gates);
145 spin_unlock_bh(&tbl->gates_lock);
148 __mesh_table_free(tbl);
151 static int mesh_table_grow(struct mesh_table *oldtbl,
152 struct mesh_table *newtbl)
154 struct hlist_head *oldhash;
155 struct hlist_node *p, *q;
158 if (atomic_read(&oldtbl->entries)
159 < oldtbl->mean_chain_len * (oldtbl->hash_mask + 1))
162 newtbl->free_node = oldtbl->free_node;
163 newtbl->mean_chain_len = oldtbl->mean_chain_len;
164 newtbl->copy_node = oldtbl->copy_node;
165 newtbl->known_gates = oldtbl->known_gates;
166 atomic_set(&newtbl->entries, atomic_read(&oldtbl->entries));
168 oldhash = oldtbl->hash_buckets;
169 for (i = 0; i <= oldtbl->hash_mask; i++)
170 hlist_for_each(p, &oldhash[i])
171 if (oldtbl->copy_node(p, newtbl) < 0)
177 for (i = 0; i <= newtbl->hash_mask; i++) {
178 hlist_for_each_safe(p, q, &newtbl->hash_buckets[i])
179 oldtbl->free_node(p, 0);
184 static u32 mesh_table_hash(const u8 *addr, struct ieee80211_sub_if_data *sdata,
185 struct mesh_table *tbl)
187 /* Use last four bytes of hw addr and interface index as hash index */
188 return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex, tbl->hash_rnd)
195 * mesh_path_assign_nexthop - update mesh path next hop
197 * @mpath: mesh path to update
198 * @sta: next hop to assign
200 * Locking: mpath->state_lock must be held when calling this function
202 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
205 struct ieee80211_hdr *hdr;
208 rcu_assign_pointer(mpath->next_hop, sta);
210 spin_lock_irqsave(&mpath->frame_queue.lock, flags);
211 skb_queue_walk(&mpath->frame_queue, skb) {
212 hdr = (struct ieee80211_hdr *) skb->data;
213 memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
214 memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
215 ieee80211_mps_set_frame_flags(sta->sdata, sta, hdr);
218 spin_unlock_irqrestore(&mpath->frame_queue.lock, flags);
221 static void prepare_for_gate(struct sk_buff *skb, char *dst_addr,
222 struct mesh_path *gate_mpath)
224 struct ieee80211_hdr *hdr;
225 struct ieee80211s_hdr *mshdr;
226 int mesh_hdrlen, hdrlen;
229 hdr = (struct ieee80211_hdr *) skb->data;
230 hdrlen = ieee80211_hdrlen(hdr->frame_control);
231 mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
233 if (!(mshdr->flags & MESH_FLAGS_AE)) {
234 /* size of the fixed part of the mesh header */
237 /* make room for the two extended addresses */
238 skb_push(skb, 2 * ETH_ALEN);
239 memmove(skb->data, hdr, hdrlen + mesh_hdrlen);
241 hdr = (struct ieee80211_hdr *) skb->data;
243 /* we preserve the previous mesh header and only add
244 * the new addreses */
245 mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
246 mshdr->flags = MESH_FLAGS_AE_A5_A6;
247 memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN);
248 memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN);
251 /* update next hop */
252 hdr = (struct ieee80211_hdr *) skb->data;
254 next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr;
255 memcpy(hdr->addr1, next_hop, ETH_ALEN);
257 memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN);
258 memcpy(hdr->addr3, dst_addr, ETH_ALEN);
263 * mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
265 * This function is used to transfer or copy frames from an unresolved mpath to
266 * a gate mpath. The function also adds the Address Extension field and
267 * updates the next hop.
269 * If a frame already has an Address Extension field, only the next hop and
270 * destination addresses are updated.
272 * The gate mpath must be an active mpath with a valid mpath->next_hop.
274 * @mpath: An active mpath the frames will be sent to (i.e. the gate)
275 * @from_mpath: The failed mpath
276 * @copy: When true, copy all the frames to the new mpath queue. When false,
279 static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
280 struct mesh_path *from_mpath,
283 struct sk_buff *skb, *fskb, *tmp;
284 struct sk_buff_head failq;
287 BUG_ON(gate_mpath == from_mpath);
288 BUG_ON(!gate_mpath->next_hop);
290 __skb_queue_head_init(&failq);
292 spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
293 skb_queue_splice_init(&from_mpath->frame_queue, &failq);
294 spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
296 skb_queue_walk_safe(&failq, fskb, tmp) {
297 if (skb_queue_len(&gate_mpath->frame_queue) >=
298 MESH_FRAME_QUEUE_LEN) {
299 mpath_dbg(gate_mpath->sdata, "mpath queue full!\n");
303 skb = skb_copy(fskb, GFP_ATOMIC);
307 prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
308 skb_queue_tail(&gate_mpath->frame_queue, skb);
313 __skb_unlink(fskb, &failq);
317 mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n",
318 gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue));
323 spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
324 skb_queue_splice(&failq, &from_mpath->frame_queue);
325 spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
329 static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
330 struct ieee80211_sub_if_data *sdata)
332 struct mesh_path *mpath;
333 struct hlist_node *n;
334 struct hlist_head *bucket;
335 struct mpath_node *node;
337 bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
338 hlist_for_each_entry_rcu(node, n, bucket, list) {
340 if (mpath->sdata == sdata &&
341 ether_addr_equal(dst, mpath->dst)) {
342 if (MPATH_EXPIRED(mpath)) {
343 spin_lock_bh(&mpath->state_lock);
344 mpath->flags &= ~MESH_PATH_ACTIVE;
345 spin_unlock_bh(&mpath->state_lock);
354 * mesh_path_lookup - look up a path in the mesh path table
355 * @dst: hardware address (ETH_ALEN length) of destination
356 * @sdata: local subif
358 * Returns: pointer to the mesh path structure, or NULL if not found
360 * Locking: must be called within a read rcu section.
362 struct mesh_path *mesh_path_lookup(const u8 *dst,
363 struct ieee80211_sub_if_data *sdata)
365 return mpath_lookup(rcu_dereference(mesh_paths), dst, sdata);
368 struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
370 return mpath_lookup(rcu_dereference(mpp_paths), dst, sdata);
375 * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
377 * @sdata: local subif, or NULL for all entries
379 * Returns: pointer to the mesh path structure, or NULL if not found.
381 * Locking: must be called within a read rcu section.
383 struct mesh_path *mesh_path_lookup_by_idx(int idx, struct ieee80211_sub_if_data *sdata)
385 struct mesh_table *tbl = rcu_dereference(mesh_paths);
386 struct mpath_node *node;
387 struct hlist_node *p;
391 for_each_mesh_entry(tbl, p, node, i) {
392 if (sdata && node->mpath->sdata != sdata)
395 if (MPATH_EXPIRED(node->mpath)) {
396 spin_lock_bh(&node->mpath->state_lock);
397 node->mpath->flags &= ~MESH_PATH_ACTIVE;
398 spin_unlock_bh(&node->mpath->state_lock);
408 * mesh_path_add_gate - add the given mpath to a mesh gate to our path table
409 * @mpath: gate path to add to table
411 int mesh_path_add_gate(struct mesh_path *mpath)
413 struct mesh_table *tbl;
414 struct mpath_node *gate, *new_gate;
415 struct hlist_node *n;
419 tbl = rcu_dereference(mesh_paths);
421 hlist_for_each_entry_rcu(gate, n, tbl->known_gates, list)
422 if (gate->mpath == mpath) {
427 new_gate = kzalloc(sizeof(struct mpath_node), GFP_ATOMIC);
433 mpath->is_gate = true;
434 mpath->sdata->u.mesh.num_gates++;
435 new_gate->mpath = mpath;
436 spin_lock_bh(&tbl->gates_lock);
437 hlist_add_head_rcu(&new_gate->list, tbl->known_gates);
438 spin_unlock_bh(&tbl->gates_lock);
440 mpath_dbg(mpath->sdata,
441 "Mesh path: Recorded new gate: %pM. %d known gates\n",
442 mpath->dst, mpath->sdata->u.mesh.num_gates);
450 * mesh_gate_del - remove a mesh gate from the list of known gates
451 * @tbl: table which holds our list of known gates
454 * Returns: 0 on success
456 * Locking: must be called inside rcu_read_lock() section
458 static int mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
460 struct mpath_node *gate;
461 struct hlist_node *p, *q;
463 hlist_for_each_entry_safe(gate, p, q, tbl->known_gates, list)
464 if (gate->mpath == mpath) {
465 spin_lock_bh(&tbl->gates_lock);
466 hlist_del_rcu(&gate->list);
467 kfree_rcu(gate, rcu);
468 spin_unlock_bh(&tbl->gates_lock);
469 mpath->sdata->u.mesh.num_gates--;
470 mpath->is_gate = false;
471 mpath_dbg(mpath->sdata,
472 "Mesh path: Deleted gate: %pM. %d known gates\n",
473 mpath->dst, mpath->sdata->u.mesh.num_gates);
481 * mesh_gate_num - number of gates known to this interface
484 int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
486 return sdata->u.mesh.num_gates;
490 * mesh_path_add - allocate and add a new path to the mesh path table
491 * @addr: destination address of the path (ETH_ALEN length)
492 * @sdata: local subif
494 * Returns: 0 on success
496 * State: the initial state of the new path is set to 0
498 int mesh_path_add(const u8 *dst, struct ieee80211_sub_if_data *sdata)
500 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
501 struct ieee80211_local *local = sdata->local;
502 struct mesh_table *tbl;
503 struct mesh_path *mpath, *new_mpath;
504 struct mpath_node *node, *new_node;
505 struct hlist_head *bucket;
506 struct hlist_node *n;
511 if (ether_addr_equal(dst, sdata->vif.addr))
512 /* never add ourselves as neighbours */
515 if (is_multicast_ether_addr(dst))
518 if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
522 new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
526 new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
530 read_lock_bh(&pathtbl_resize_lock);
531 memcpy(new_mpath->dst, dst, ETH_ALEN);
532 eth_broadcast_addr(new_mpath->rann_snd_addr);
533 new_mpath->is_root = false;
534 new_mpath->sdata = sdata;
535 new_mpath->flags = 0;
536 skb_queue_head_init(&new_mpath->frame_queue);
537 new_node->mpath = new_mpath;
538 new_mpath->timer.data = (unsigned long) new_mpath;
539 new_mpath->timer.function = mesh_path_timer;
540 new_mpath->exp_time = jiffies;
541 spin_lock_init(&new_mpath->state_lock);
542 init_timer(&new_mpath->timer);
544 tbl = resize_dereference_mesh_paths();
546 hash_idx = mesh_table_hash(dst, sdata, tbl);
547 bucket = &tbl->hash_buckets[hash_idx];
549 spin_lock(&tbl->hashwlock[hash_idx]);
552 hlist_for_each_entry(node, n, bucket, list) {
554 if (mpath->sdata == sdata &&
555 ether_addr_equal(dst, mpath->dst))
559 hlist_add_head_rcu(&new_node->list, bucket);
560 if (atomic_inc_return(&tbl->entries) >=
561 tbl->mean_chain_len * (tbl->hash_mask + 1))
564 mesh_paths_generation++;
566 spin_unlock(&tbl->hashwlock[hash_idx]);
567 read_unlock_bh(&pathtbl_resize_lock);
569 set_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags);
570 ieee80211_queue_work(&local->hw, &sdata->work);
575 spin_unlock(&tbl->hashwlock[hash_idx]);
576 read_unlock_bh(&pathtbl_resize_lock);
581 atomic_dec(&sdata->u.mesh.mpaths);
585 static void mesh_table_free_rcu(struct rcu_head *rcu)
587 struct mesh_table *tbl = container_of(rcu, struct mesh_table, rcu_head);
589 mesh_table_free(tbl, false);
592 void mesh_mpath_table_grow(void)
594 struct mesh_table *oldtbl, *newtbl;
596 write_lock_bh(&pathtbl_resize_lock);
597 oldtbl = resize_dereference_mesh_paths();
598 newtbl = mesh_table_alloc(oldtbl->size_order + 1);
601 if (mesh_table_grow(oldtbl, newtbl) < 0) {
602 __mesh_table_free(newtbl);
605 rcu_assign_pointer(mesh_paths, newtbl);
607 call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
610 write_unlock_bh(&pathtbl_resize_lock);
613 void mesh_mpp_table_grow(void)
615 struct mesh_table *oldtbl, *newtbl;
617 write_lock_bh(&pathtbl_resize_lock);
618 oldtbl = resize_dereference_mpp_paths();
619 newtbl = mesh_table_alloc(oldtbl->size_order + 1);
622 if (mesh_table_grow(oldtbl, newtbl) < 0) {
623 __mesh_table_free(newtbl);
626 rcu_assign_pointer(mpp_paths, newtbl);
627 call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
630 write_unlock_bh(&pathtbl_resize_lock);
633 int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
635 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
636 struct ieee80211_local *local = sdata->local;
637 struct mesh_table *tbl;
638 struct mesh_path *mpath, *new_mpath;
639 struct mpath_node *node, *new_node;
640 struct hlist_head *bucket;
641 struct hlist_node *n;
646 if (ether_addr_equal(dst, sdata->vif.addr))
647 /* never add ourselves as neighbours */
650 if (is_multicast_ether_addr(dst))
654 new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
658 new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
662 read_lock_bh(&pathtbl_resize_lock);
663 memcpy(new_mpath->dst, dst, ETH_ALEN);
664 memcpy(new_mpath->mpp, mpp, ETH_ALEN);
665 new_mpath->sdata = sdata;
666 new_mpath->flags = 0;
667 skb_queue_head_init(&new_mpath->frame_queue);
668 new_node->mpath = new_mpath;
669 init_timer(&new_mpath->timer);
670 new_mpath->exp_time = jiffies;
671 spin_lock_init(&new_mpath->state_lock);
673 tbl = resize_dereference_mpp_paths();
675 hash_idx = mesh_table_hash(dst, sdata, tbl);
676 bucket = &tbl->hash_buckets[hash_idx];
678 spin_lock(&tbl->hashwlock[hash_idx]);
681 hlist_for_each_entry(node, n, bucket, list) {
683 if (mpath->sdata == sdata &&
684 ether_addr_equal(dst, mpath->dst))
688 hlist_add_head_rcu(&new_node->list, bucket);
689 if (atomic_inc_return(&tbl->entries) >=
690 tbl->mean_chain_len * (tbl->hash_mask + 1))
693 spin_unlock(&tbl->hashwlock[hash_idx]);
694 read_unlock_bh(&pathtbl_resize_lock);
696 set_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags);
697 ieee80211_queue_work(&local->hw, &sdata->work);
702 spin_unlock(&tbl->hashwlock[hash_idx]);
703 read_unlock_bh(&pathtbl_resize_lock);
713 * mesh_plink_broken - deactivates paths and sends perr when a link breaks
715 * @sta: broken peer link
717 * This function must be called from the rate control algorithm if enough
718 * delivery errors suggest that a peer link is no longer usable.
720 void mesh_plink_broken(struct sta_info *sta)
722 struct mesh_table *tbl;
723 static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
724 struct mesh_path *mpath;
725 struct mpath_node *node;
726 struct hlist_node *p;
727 struct ieee80211_sub_if_data *sdata = sta->sdata;
729 __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_DEST_UNREACHABLE);
732 tbl = rcu_dereference(mesh_paths);
733 for_each_mesh_entry(tbl, p, node, i) {
735 if (rcu_dereference(mpath->next_hop) == sta &&
736 mpath->flags & MESH_PATH_ACTIVE &&
737 !(mpath->flags & MESH_PATH_FIXED)) {
738 spin_lock_bh(&mpath->state_lock);
739 mpath->flags &= ~MESH_PATH_ACTIVE;
741 spin_unlock_bh(&mpath->state_lock);
742 mesh_path_error_tx(sdata->u.mesh.mshcfg.element_ttl,
743 mpath->dst, cpu_to_le32(mpath->sn),
744 reason, bcast, sdata);
750 static void mesh_path_node_reclaim(struct rcu_head *rp)
752 struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
753 struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
755 del_timer_sync(&node->mpath->timer);
756 atomic_dec(&sdata->u.mesh.mpaths);
761 /* needs to be called with the corresponding hashwlock taken */
762 static void __mesh_path_del(struct mesh_table *tbl, struct mpath_node *node)
764 struct mesh_path *mpath;
766 spin_lock(&mpath->state_lock);
767 mpath->flags |= MESH_PATH_RESOLVING;
769 mesh_gate_del(tbl, mpath);
770 hlist_del_rcu(&node->list);
771 call_rcu(&node->rcu, mesh_path_node_reclaim);
772 spin_unlock(&mpath->state_lock);
773 atomic_dec(&tbl->entries);
777 * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
779 * @sta: mesh peer to match
781 * RCU notes: this function is called when a mesh plink transitions from
782 * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
783 * allows path creation. This will happen before the sta can be freed (because
784 * sta_info_destroy() calls this) so any reader in a rcu read block will be
785 * protected against the plink disappearing.
787 void mesh_path_flush_by_nexthop(struct sta_info *sta)
789 struct mesh_table *tbl;
790 struct mesh_path *mpath;
791 struct mpath_node *node;
792 struct hlist_node *p;
796 read_lock_bh(&pathtbl_resize_lock);
797 tbl = resize_dereference_mesh_paths();
798 for_each_mesh_entry(tbl, p, node, i) {
800 if (rcu_dereference(mpath->next_hop) == sta) {
801 spin_lock(&tbl->hashwlock[i]);
802 __mesh_path_del(tbl, node);
803 spin_unlock(&tbl->hashwlock[i]);
806 read_unlock_bh(&pathtbl_resize_lock);
810 static void table_flush_by_iface(struct mesh_table *tbl,
811 struct ieee80211_sub_if_data *sdata)
813 struct mesh_path *mpath;
814 struct mpath_node *node;
815 struct hlist_node *p;
818 WARN_ON(!rcu_read_lock_held());
819 for_each_mesh_entry(tbl, p, node, i) {
821 if (mpath->sdata != sdata)
823 spin_lock_bh(&tbl->hashwlock[i]);
824 __mesh_path_del(tbl, node);
825 spin_unlock_bh(&tbl->hashwlock[i]);
830 * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
832 * This function deletes both mesh paths as well as mesh portal paths.
834 * @sdata: interface data to match
837 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
839 struct mesh_table *tbl;
842 read_lock_bh(&pathtbl_resize_lock);
843 tbl = resize_dereference_mesh_paths();
844 table_flush_by_iface(tbl, sdata);
845 tbl = resize_dereference_mpp_paths();
846 table_flush_by_iface(tbl, sdata);
847 read_unlock_bh(&pathtbl_resize_lock);
852 * mesh_path_del - delete a mesh path from the table
854 * @addr: dst address (ETH_ALEN length)
855 * @sdata: local subif
857 * Returns: 0 if successful
859 int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
861 struct mesh_table *tbl;
862 struct mesh_path *mpath;
863 struct mpath_node *node;
864 struct hlist_head *bucket;
865 struct hlist_node *n;
869 read_lock_bh(&pathtbl_resize_lock);
870 tbl = resize_dereference_mesh_paths();
871 hash_idx = mesh_table_hash(addr, sdata, tbl);
872 bucket = &tbl->hash_buckets[hash_idx];
874 spin_lock(&tbl->hashwlock[hash_idx]);
875 hlist_for_each_entry(node, n, bucket, list) {
877 if (mpath->sdata == sdata &&
878 ether_addr_equal(addr, mpath->dst)) {
879 __mesh_path_del(tbl, node);
886 mesh_paths_generation++;
887 spin_unlock(&tbl->hashwlock[hash_idx]);
888 read_unlock_bh(&pathtbl_resize_lock);
893 * mesh_path_tx_pending - sends pending frames in a mesh path queue
895 * @mpath: mesh path to activate
897 * Locking: the state_lock of the mpath structure must NOT be held when calling
900 void mesh_path_tx_pending(struct mesh_path *mpath)
902 if (mpath->flags & MESH_PATH_ACTIVE)
903 ieee80211_add_pending_skbs(mpath->sdata->local,
904 &mpath->frame_queue);
908 * mesh_path_send_to_gates - sends pending frames to all known mesh gates
910 * @mpath: mesh path whose queue will be emptied
912 * If there is only one gate, the frames are transferred from the failed mpath
913 * queue to that gate's queue. If there are more than one gates, the frames
914 * are copied from each gate to the next. After frames are copied, the
915 * mpath queues are emptied onto the transmission queue.
917 int mesh_path_send_to_gates(struct mesh_path *mpath)
919 struct ieee80211_sub_if_data *sdata = mpath->sdata;
920 struct hlist_node *n;
921 struct mesh_table *tbl;
922 struct mesh_path *from_mpath = mpath;
923 struct mpath_node *gate = NULL;
925 struct hlist_head *known_gates;
928 tbl = rcu_dereference(mesh_paths);
929 known_gates = tbl->known_gates;
933 return -EHOSTUNREACH;
935 hlist_for_each_entry_rcu(gate, n, known_gates, list) {
936 if (gate->mpath->sdata != sdata)
939 if (gate->mpath->flags & MESH_PATH_ACTIVE) {
940 mpath_dbg(sdata, "Forwarding to %pM\n", gate->mpath->dst);
941 mesh_path_move_to_queue(gate->mpath, from_mpath, copy);
942 from_mpath = gate->mpath;
946 "Not forwarding %p (flags %#x)\n",
947 gate->mpath, gate->mpath->flags);
951 hlist_for_each_entry_rcu(gate, n, known_gates, list)
952 if (gate->mpath->sdata == sdata) {
953 mpath_dbg(sdata, "Sending to %pM\n", gate->mpath->dst);
954 mesh_path_tx_pending(gate->mpath);
957 return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
961 * mesh_path_discard_frame - discard a frame whose path could not be resolved
963 * @skb: frame to discard
964 * @sdata: network subif the frame was to be sent through
966 * Locking: the function must me called within a rcu_read_lock region
968 void mesh_path_discard_frame(struct sk_buff *skb,
969 struct ieee80211_sub_if_data *sdata)
972 sdata->u.mesh.mshstats.dropped_frames_no_route++;
976 * mesh_path_flush_pending - free the pending queue of a mesh path
978 * @mpath: mesh path whose queue has to be freed
980 * Locking: the function must me called within a rcu_read_lock region
982 void mesh_path_flush_pending(struct mesh_path *mpath)
986 while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL)
987 mesh_path_discard_frame(skb, mpath->sdata);
991 * mesh_path_fix_nexthop - force a specific next hop for a mesh path
993 * @mpath: the mesh path to modify
994 * @next_hop: the next hop to force
996 * Locking: this function must be called holding mpath->state_lock
998 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
1000 spin_lock_bh(&mpath->state_lock);
1001 mesh_path_assign_nexthop(mpath, next_hop);
1004 mpath->hop_count = 0;
1005 mpath->exp_time = 0;
1006 mpath->flags |= MESH_PATH_FIXED;
1007 mesh_path_activate(mpath);
1008 spin_unlock_bh(&mpath->state_lock);
1009 mesh_path_tx_pending(mpath);
1012 static void mesh_path_node_free(struct hlist_node *p, bool free_leafs)
1014 struct mesh_path *mpath;
1015 struct mpath_node *node = hlist_entry(p, struct mpath_node, list);
1016 mpath = node->mpath;
1019 del_timer_sync(&mpath->timer);
1025 static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
1027 struct mesh_path *mpath;
1028 struct mpath_node *node, *new_node;
1031 new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
1032 if (new_node == NULL)
1035 node = hlist_entry(p, struct mpath_node, list);
1036 mpath = node->mpath;
1037 new_node->mpath = mpath;
1038 hash_idx = mesh_table_hash(mpath->dst, mpath->sdata, newtbl);
1039 hlist_add_head(&new_node->list,
1040 &newtbl->hash_buckets[hash_idx]);
1044 int mesh_pathtbl_init(void)
1046 struct mesh_table *tbl_path, *tbl_mpp;
1049 tbl_path = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
1052 tbl_path->free_node = &mesh_path_node_free;
1053 tbl_path->copy_node = &mesh_path_node_copy;
1054 tbl_path->mean_chain_len = MEAN_CHAIN_LEN;
1055 tbl_path->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
1056 if (!tbl_path->known_gates) {
1060 INIT_HLIST_HEAD(tbl_path->known_gates);
1063 tbl_mpp = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
1068 tbl_mpp->free_node = &mesh_path_node_free;
1069 tbl_mpp->copy_node = &mesh_path_node_copy;
1070 tbl_mpp->mean_chain_len = MEAN_CHAIN_LEN;
1071 tbl_mpp->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
1072 if (!tbl_mpp->known_gates) {
1076 INIT_HLIST_HEAD(tbl_mpp->known_gates);
1078 /* Need no locking since this is during init */
1079 RCU_INIT_POINTER(mesh_paths, tbl_path);
1080 RCU_INIT_POINTER(mpp_paths, tbl_mpp);
1085 mesh_table_free(tbl_mpp, true);
1087 mesh_table_free(tbl_path, true);
1091 void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
1093 struct mesh_table *tbl;
1094 struct mesh_path *mpath;
1095 struct mpath_node *node;
1096 struct hlist_node *p;
1100 tbl = rcu_dereference(mesh_paths);
1101 for_each_mesh_entry(tbl, p, node, i) {
1102 if (node->mpath->sdata != sdata)
1104 mpath = node->mpath;
1105 if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
1106 (!(mpath->flags & MESH_PATH_FIXED)) &&
1107 time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
1108 mesh_path_del(mpath->dst, mpath->sdata);
1113 void mesh_pathtbl_unregister(void)
1115 /* no need for locking during exit path */
1116 mesh_table_free(rcu_dereference_protected(mesh_paths, 1), true);
1117 mesh_table_free(rcu_dereference_protected(mpp_paths, 1), true);