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 static inline bool mpath_expired(struct mesh_path *mpath)
29 return (mpath->flags & MESH_PATH_ACTIVE) &&
30 time_after(jiffies, mpath->exp_time) &&
31 !(mpath->flags & MESH_PATH_FIXED);
35 struct hlist_node list;
37 /* This indirection allows two different tables to point to the same
38 * mesh_path structure, useful when resizing
40 struct mesh_path *mpath;
43 static struct mesh_table __rcu *mesh_paths;
44 static struct mesh_table __rcu *mpp_paths; /* Store paths for MPP&MAP */
46 int mesh_paths_generation;
48 /* This lock will have the grow table function as writer and add / delete nodes
49 * as readers. RCU provides sufficient protection only when reading the table
50 * (i.e. doing lookups). Adding or adding or removing nodes requires we take
51 * the read lock or we risk operating on an old table. The write lock is only
52 * needed when modifying the number of buckets a table.
54 static DEFINE_RWLOCK(pathtbl_resize_lock);
57 static inline struct mesh_table *resize_dereference_mesh_paths(void)
59 return rcu_dereference_protected(mesh_paths,
60 lockdep_is_held(&pathtbl_resize_lock));
63 static inline struct mesh_table *resize_dereference_mpp_paths(void)
65 return rcu_dereference_protected(mpp_paths,
66 lockdep_is_held(&pathtbl_resize_lock));
70 * CAREFUL -- "tbl" must not be an expression,
71 * in particular not an rcu_dereference(), since
72 * it's used twice. So it is illegal to do
73 * for_each_mesh_entry(rcu_dereference(...), ...)
75 #define for_each_mesh_entry(tbl, p, node, i) \
76 for (i = 0; i <= tbl->hash_mask; i++) \
77 hlist_for_each_entry_rcu(node, p, &tbl->hash_buckets[i], list)
80 static struct mesh_table *mesh_table_alloc(int size_order)
83 struct mesh_table *newtbl;
85 newtbl = kmalloc(sizeof(struct mesh_table), GFP_ATOMIC);
89 newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
90 (1 << size_order), GFP_ATOMIC);
92 if (!newtbl->hash_buckets) {
97 newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
98 (1 << size_order), GFP_ATOMIC);
99 if (!newtbl->hashwlock) {
100 kfree(newtbl->hash_buckets);
105 newtbl->size_order = size_order;
106 newtbl->hash_mask = (1 << size_order) - 1;
107 atomic_set(&newtbl->entries, 0);
108 get_random_bytes(&newtbl->hash_rnd,
109 sizeof(newtbl->hash_rnd));
110 for (i = 0; i <= newtbl->hash_mask; i++)
111 spin_lock_init(&newtbl->hashwlock[i]);
112 spin_lock_init(&newtbl->gates_lock);
117 static void __mesh_table_free(struct mesh_table *tbl)
119 kfree(tbl->hash_buckets);
120 kfree(tbl->hashwlock);
124 static void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
126 struct hlist_head *mesh_hash;
127 struct hlist_node *p, *q;
128 struct mpath_node *gate;
131 mesh_hash = tbl->hash_buckets;
132 for (i = 0; i <= tbl->hash_mask; i++) {
133 spin_lock_bh(&tbl->hashwlock[i]);
134 hlist_for_each_safe(p, q, &mesh_hash[i]) {
135 tbl->free_node(p, free_leafs);
136 atomic_dec(&tbl->entries);
138 spin_unlock_bh(&tbl->hashwlock[i]);
141 spin_lock_bh(&tbl->gates_lock);
142 hlist_for_each_entry_safe(gate, p, q,
143 tbl->known_gates, list) {
144 hlist_del(&gate->list);
147 kfree(tbl->known_gates);
148 spin_unlock_bh(&tbl->gates_lock);
151 __mesh_table_free(tbl);
154 static int mesh_table_grow(struct mesh_table *oldtbl,
155 struct mesh_table *newtbl)
157 struct hlist_head *oldhash;
158 struct hlist_node *p, *q;
161 if (atomic_read(&oldtbl->entries)
162 < oldtbl->mean_chain_len * (oldtbl->hash_mask + 1))
165 newtbl->free_node = oldtbl->free_node;
166 newtbl->mean_chain_len = oldtbl->mean_chain_len;
167 newtbl->copy_node = oldtbl->copy_node;
168 newtbl->known_gates = oldtbl->known_gates;
169 atomic_set(&newtbl->entries, atomic_read(&oldtbl->entries));
171 oldhash = oldtbl->hash_buckets;
172 for (i = 0; i <= oldtbl->hash_mask; i++)
173 hlist_for_each(p, &oldhash[i])
174 if (oldtbl->copy_node(p, newtbl) < 0)
180 for (i = 0; i <= newtbl->hash_mask; i++) {
181 hlist_for_each_safe(p, q, &newtbl->hash_buckets[i])
182 oldtbl->free_node(p, 0);
187 static u32 mesh_table_hash(const u8 *addr, struct ieee80211_sub_if_data *sdata,
188 struct mesh_table *tbl)
190 /* Use last four bytes of hw addr and interface index as hash index */
191 return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex,
192 tbl->hash_rnd) & tbl->hash_mask;
198 * mesh_path_assign_nexthop - update mesh path next hop
200 * @mpath: mesh path to update
201 * @sta: next hop to assign
203 * Locking: mpath->state_lock must be held when calling this function
205 void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
208 struct ieee80211_hdr *hdr;
211 rcu_assign_pointer(mpath->next_hop, sta);
213 spin_lock_irqsave(&mpath->frame_queue.lock, flags);
214 skb_queue_walk(&mpath->frame_queue, skb) {
215 hdr = (struct ieee80211_hdr *) skb->data;
216 memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
217 memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
218 ieee80211_mps_set_frame_flags(sta->sdata, sta, hdr);
221 spin_unlock_irqrestore(&mpath->frame_queue.lock, flags);
224 static void prepare_for_gate(struct sk_buff *skb, char *dst_addr,
225 struct mesh_path *gate_mpath)
227 struct ieee80211_hdr *hdr;
228 struct ieee80211s_hdr *mshdr;
229 int mesh_hdrlen, hdrlen;
232 hdr = (struct ieee80211_hdr *) skb->data;
233 hdrlen = ieee80211_hdrlen(hdr->frame_control);
234 mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
236 if (!(mshdr->flags & MESH_FLAGS_AE)) {
237 /* size of the fixed part of the mesh header */
240 /* make room for the two extended addresses */
241 skb_push(skb, 2 * ETH_ALEN);
242 memmove(skb->data, hdr, hdrlen + mesh_hdrlen);
244 hdr = (struct ieee80211_hdr *) skb->data;
246 /* we preserve the previous mesh header and only add
247 * the new addreses */
248 mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
249 mshdr->flags = MESH_FLAGS_AE_A5_A6;
250 memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN);
251 memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN);
254 /* update next hop */
255 hdr = (struct ieee80211_hdr *) skb->data;
257 next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr;
258 memcpy(hdr->addr1, next_hop, ETH_ALEN);
260 memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN);
261 memcpy(hdr->addr3, dst_addr, ETH_ALEN);
266 * mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
268 * This function is used to transfer or copy frames from an unresolved mpath to
269 * a gate mpath. The function also adds the Address Extension field and
270 * updates the next hop.
272 * If a frame already has an Address Extension field, only the next hop and
273 * destination addresses are updated.
275 * The gate mpath must be an active mpath with a valid mpath->next_hop.
277 * @mpath: An active mpath the frames will be sent to (i.e. the gate)
278 * @from_mpath: The failed mpath
279 * @copy: When true, copy all the frames to the new mpath queue. When false,
282 static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
283 struct mesh_path *from_mpath,
286 struct sk_buff *skb, *fskb, *tmp;
287 struct sk_buff_head failq;
290 BUG_ON(gate_mpath == from_mpath);
291 BUG_ON(!gate_mpath->next_hop);
293 __skb_queue_head_init(&failq);
295 spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
296 skb_queue_splice_init(&from_mpath->frame_queue, &failq);
297 spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
299 skb_queue_walk_safe(&failq, fskb, tmp) {
300 if (skb_queue_len(&gate_mpath->frame_queue) >=
301 MESH_FRAME_QUEUE_LEN) {
302 mpath_dbg(gate_mpath->sdata, "mpath queue full!\n");
306 skb = skb_copy(fskb, GFP_ATOMIC);
310 prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
311 skb_queue_tail(&gate_mpath->frame_queue, skb);
316 __skb_unlink(fskb, &failq);
320 mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n",
321 gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue));
326 spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
327 skb_queue_splice(&failq, &from_mpath->frame_queue);
328 spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
332 static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
333 struct ieee80211_sub_if_data *sdata)
335 struct mesh_path *mpath;
336 struct hlist_node *n;
337 struct hlist_head *bucket;
338 struct mpath_node *node;
340 bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
341 hlist_for_each_entry_rcu(node, n, bucket, list) {
343 if (mpath->sdata == sdata &&
344 ether_addr_equal(dst, mpath->dst)) {
345 if (mpath_expired(mpath)) {
346 spin_lock_bh(&mpath->state_lock);
347 mpath->flags &= ~MESH_PATH_ACTIVE;
348 spin_unlock_bh(&mpath->state_lock);
357 * mesh_path_lookup - look up a path in the mesh path table
358 * @sdata: local subif
359 * @dst: hardware address (ETH_ALEN length) of destination
361 * Returns: pointer to the mesh path structure, or NULL if not found
363 * Locking: must be called within a read rcu section.
366 mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
368 return mpath_lookup(rcu_dereference(mesh_paths), dst, sdata);
372 mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
374 return mpath_lookup(rcu_dereference(mpp_paths), dst, sdata);
379 * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
381 * @sdata: local subif, or NULL for all entries
383 * Returns: pointer to the mesh path structure, or NULL if not found.
385 * Locking: must be called within a read rcu section.
388 mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
390 struct mesh_table *tbl = rcu_dereference(mesh_paths);
391 struct mpath_node *node;
392 struct hlist_node *p;
396 for_each_mesh_entry(tbl, p, node, i) {
397 if (sdata && node->mpath->sdata != sdata)
400 if (mpath_expired(node->mpath)) {
401 spin_lock_bh(&node->mpath->state_lock);
402 node->mpath->flags &= ~MESH_PATH_ACTIVE;
403 spin_unlock_bh(&node->mpath->state_lock);
413 * mesh_path_add_gate - add the given mpath to a mesh gate to our path table
414 * @mpath: gate path to add to table
416 int mesh_path_add_gate(struct mesh_path *mpath)
418 struct mesh_table *tbl;
419 struct mpath_node *gate, *new_gate;
420 struct hlist_node *n;
424 tbl = rcu_dereference(mesh_paths);
426 hlist_for_each_entry_rcu(gate, n, tbl->known_gates, list)
427 if (gate->mpath == mpath) {
432 new_gate = kzalloc(sizeof(struct mpath_node), GFP_ATOMIC);
438 mpath->is_gate = true;
439 mpath->sdata->u.mesh.num_gates++;
440 new_gate->mpath = mpath;
441 spin_lock_bh(&tbl->gates_lock);
442 hlist_add_head_rcu(&new_gate->list, tbl->known_gates);
443 spin_unlock_bh(&tbl->gates_lock);
444 mpath_dbg(mpath->sdata,
445 "Mesh path: Recorded new gate: %pM. %d known gates\n",
446 mpath->dst, mpath->sdata->u.mesh.num_gates);
454 * mesh_gate_del - remove a mesh gate from the list of known gates
455 * @tbl: table which holds our list of known gates
458 * Locking: must be called inside rcu_read_lock() section
460 static void mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
462 struct mpath_node *gate;
463 struct hlist_node *p, *q;
465 hlist_for_each_entry_safe(gate, p, q, tbl->known_gates, list) {
466 if (gate->mpath != mpath)
468 spin_lock_bh(&tbl->gates_lock);
469 hlist_del_rcu(&gate->list);
470 kfree_rcu(gate, rcu);
471 spin_unlock_bh(&tbl->gates_lock);
472 mpath->sdata->u.mesh.num_gates--;
473 mpath->is_gate = false;
474 mpath_dbg(mpath->sdata,
475 "Mesh path: Deleted gate: %pM. %d known gates\n",
476 mpath->dst, mpath->sdata->u.mesh.num_gates);
482 * mesh_gate_num - number of gates known to this interface
485 int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
487 return sdata->u.mesh.num_gates;
491 * mesh_path_add - allocate and add a new path to the mesh path table
492 * @dst: destination address of the path (ETH_ALEN length)
493 * @sdata: local subif
495 * Returns: 0 on success
497 * State: the initial state of the new path is set to 0
499 int mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst)
501 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
502 struct ieee80211_local *local = sdata->local;
503 struct mesh_table *tbl;
504 struct mesh_path *mpath, *new_mpath;
505 struct mpath_node *node, *new_node;
506 struct hlist_head *bucket;
507 struct hlist_node *n;
512 if (ether_addr_equal(dst, sdata->vif.addr))
513 /* never add ourselves as neighbours */
516 if (is_multicast_ether_addr(dst))
519 if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
523 new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
527 new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
531 read_lock_bh(&pathtbl_resize_lock);
532 memcpy(new_mpath->dst, dst, ETH_ALEN);
533 eth_broadcast_addr(new_mpath->rann_snd_addr);
534 new_mpath->is_root = false;
535 new_mpath->sdata = sdata;
536 new_mpath->flags = 0;
537 skb_queue_head_init(&new_mpath->frame_queue);
538 new_node->mpath = new_mpath;
539 new_mpath->timer.data = (unsigned long) new_mpath;
540 new_mpath->timer.function = mesh_path_timer;
541 new_mpath->exp_time = jiffies;
542 spin_lock_init(&new_mpath->state_lock);
543 init_timer(&new_mpath->timer);
545 tbl = resize_dereference_mesh_paths();
547 hash_idx = mesh_table_hash(dst, sdata, tbl);
548 bucket = &tbl->hash_buckets[hash_idx];
550 spin_lock(&tbl->hashwlock[hash_idx]);
553 hlist_for_each_entry(node, n, bucket, list) {
555 if (mpath->sdata == sdata &&
556 ether_addr_equal(dst, mpath->dst))
560 hlist_add_head_rcu(&new_node->list, bucket);
561 if (atomic_inc_return(&tbl->entries) >=
562 tbl->mean_chain_len * (tbl->hash_mask + 1))
565 mesh_paths_generation++;
567 spin_unlock(&tbl->hashwlock[hash_idx]);
568 read_unlock_bh(&pathtbl_resize_lock);
570 set_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags);
571 ieee80211_queue_work(&local->hw, &sdata->work);
576 spin_unlock(&tbl->hashwlock[hash_idx]);
577 read_unlock_bh(&pathtbl_resize_lock);
582 atomic_dec(&sdata->u.mesh.mpaths);
586 static void mesh_table_free_rcu(struct rcu_head *rcu)
588 struct mesh_table *tbl = container_of(rcu, struct mesh_table, rcu_head);
590 mesh_table_free(tbl, false);
593 void mesh_mpath_table_grow(void)
595 struct mesh_table *oldtbl, *newtbl;
597 write_lock_bh(&pathtbl_resize_lock);
598 oldtbl = resize_dereference_mesh_paths();
599 newtbl = mesh_table_alloc(oldtbl->size_order + 1);
602 if (mesh_table_grow(oldtbl, newtbl) < 0) {
603 __mesh_table_free(newtbl);
606 rcu_assign_pointer(mesh_paths, newtbl);
608 call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
611 write_unlock_bh(&pathtbl_resize_lock);
614 void mesh_mpp_table_grow(void)
616 struct mesh_table *oldtbl, *newtbl;
618 write_lock_bh(&pathtbl_resize_lock);
619 oldtbl = resize_dereference_mpp_paths();
620 newtbl = mesh_table_alloc(oldtbl->size_order + 1);
623 if (mesh_table_grow(oldtbl, newtbl) < 0) {
624 __mesh_table_free(newtbl);
627 rcu_assign_pointer(mpp_paths, newtbl);
628 call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
631 write_unlock_bh(&pathtbl_resize_lock);
634 int mpp_path_add(struct ieee80211_sub_if_data *sdata,
635 const u8 *dst, const u8 *mpp)
637 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
638 struct ieee80211_local *local = sdata->local;
639 struct mesh_table *tbl;
640 struct mesh_path *mpath, *new_mpath;
641 struct mpath_node *node, *new_node;
642 struct hlist_head *bucket;
643 struct hlist_node *n;
648 if (ether_addr_equal(dst, sdata->vif.addr))
649 /* never add ourselves as neighbours */
652 if (is_multicast_ether_addr(dst))
656 new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
660 new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
664 read_lock_bh(&pathtbl_resize_lock);
665 memcpy(new_mpath->dst, dst, ETH_ALEN);
666 memcpy(new_mpath->mpp, mpp, ETH_ALEN);
667 new_mpath->sdata = sdata;
668 new_mpath->flags = 0;
669 skb_queue_head_init(&new_mpath->frame_queue);
670 new_node->mpath = new_mpath;
671 init_timer(&new_mpath->timer);
672 new_mpath->exp_time = jiffies;
673 spin_lock_init(&new_mpath->state_lock);
675 tbl = resize_dereference_mpp_paths();
677 hash_idx = mesh_table_hash(dst, sdata, tbl);
678 bucket = &tbl->hash_buckets[hash_idx];
680 spin_lock(&tbl->hashwlock[hash_idx]);
683 hlist_for_each_entry(node, n, bucket, list) {
685 if (mpath->sdata == sdata &&
686 ether_addr_equal(dst, mpath->dst))
690 hlist_add_head_rcu(&new_node->list, bucket);
691 if (atomic_inc_return(&tbl->entries) >=
692 tbl->mean_chain_len * (tbl->hash_mask + 1))
695 spin_unlock(&tbl->hashwlock[hash_idx]);
696 read_unlock_bh(&pathtbl_resize_lock);
698 set_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags);
699 ieee80211_queue_work(&local->hw, &sdata->work);
704 spin_unlock(&tbl->hashwlock[hash_idx]);
705 read_unlock_bh(&pathtbl_resize_lock);
715 * mesh_plink_broken - deactivates paths and sends perr when a link breaks
717 * @sta: broken peer link
719 * This function must be called from the rate control algorithm if enough
720 * delivery errors suggest that a peer link is no longer usable.
722 void mesh_plink_broken(struct sta_info *sta)
724 struct mesh_table *tbl;
725 static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
726 struct mesh_path *mpath;
727 struct mpath_node *node;
728 struct hlist_node *p;
729 struct ieee80211_sub_if_data *sdata = sta->sdata;
731 __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_DEST_UNREACHABLE);
734 tbl = rcu_dereference(mesh_paths);
735 for_each_mesh_entry(tbl, p, node, i) {
737 if (rcu_dereference(mpath->next_hop) == sta &&
738 mpath->flags & MESH_PATH_ACTIVE &&
739 !(mpath->flags & MESH_PATH_FIXED)) {
740 spin_lock_bh(&mpath->state_lock);
741 mpath->flags &= ~MESH_PATH_ACTIVE;
743 spin_unlock_bh(&mpath->state_lock);
744 mesh_path_error_tx(sdata,
745 sdata->u.mesh.mshcfg.element_ttl,
746 mpath->dst, cpu_to_le32(mpath->sn),
753 static void mesh_path_node_reclaim(struct rcu_head *rp)
755 struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
756 struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
758 del_timer_sync(&node->mpath->timer);
759 atomic_dec(&sdata->u.mesh.mpaths);
764 /* needs to be called with the corresponding hashwlock taken */
765 static void __mesh_path_del(struct mesh_table *tbl, struct mpath_node *node)
767 struct mesh_path *mpath;
769 spin_lock(&mpath->state_lock);
770 mpath->flags |= MESH_PATH_RESOLVING;
772 mesh_gate_del(tbl, mpath);
773 hlist_del_rcu(&node->list);
774 call_rcu(&node->rcu, mesh_path_node_reclaim);
775 spin_unlock(&mpath->state_lock);
776 atomic_dec(&tbl->entries);
780 * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
782 * @sta: mesh peer to match
784 * RCU notes: this function is called when a mesh plink transitions from
785 * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
786 * allows path creation. This will happen before the sta can be freed (because
787 * sta_info_destroy() calls this) so any reader in a rcu read block will be
788 * protected against the plink disappearing.
790 void mesh_path_flush_by_nexthop(struct sta_info *sta)
792 struct mesh_table *tbl;
793 struct mesh_path *mpath;
794 struct mpath_node *node;
795 struct hlist_node *p;
799 read_lock_bh(&pathtbl_resize_lock);
800 tbl = resize_dereference_mesh_paths();
801 for_each_mesh_entry(tbl, p, node, i) {
803 if (rcu_dereference(mpath->next_hop) == sta) {
804 spin_lock(&tbl->hashwlock[i]);
805 __mesh_path_del(tbl, node);
806 spin_unlock(&tbl->hashwlock[i]);
809 read_unlock_bh(&pathtbl_resize_lock);
813 static void table_flush_by_iface(struct mesh_table *tbl,
814 struct ieee80211_sub_if_data *sdata)
816 struct mesh_path *mpath;
817 struct mpath_node *node;
818 struct hlist_node *p;
821 WARN_ON(!rcu_read_lock_held());
822 for_each_mesh_entry(tbl, p, node, i) {
824 if (mpath->sdata != sdata)
826 spin_lock_bh(&tbl->hashwlock[i]);
827 __mesh_path_del(tbl, node);
828 spin_unlock_bh(&tbl->hashwlock[i]);
833 * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
835 * This function deletes both mesh paths as well as mesh portal paths.
837 * @sdata: interface data to match
840 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
842 struct mesh_table *tbl;
845 read_lock_bh(&pathtbl_resize_lock);
846 tbl = resize_dereference_mesh_paths();
847 table_flush_by_iface(tbl, sdata);
848 tbl = resize_dereference_mpp_paths();
849 table_flush_by_iface(tbl, sdata);
850 read_unlock_bh(&pathtbl_resize_lock);
855 * mesh_path_del - delete a mesh path from the table
857 * @addr: dst address (ETH_ALEN length)
858 * @sdata: local subif
860 * Returns: 0 if successful
862 int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
864 struct mesh_table *tbl;
865 struct mesh_path *mpath;
866 struct mpath_node *node;
867 struct hlist_head *bucket;
868 struct hlist_node *n;
872 read_lock_bh(&pathtbl_resize_lock);
873 tbl = resize_dereference_mesh_paths();
874 hash_idx = mesh_table_hash(addr, sdata, tbl);
875 bucket = &tbl->hash_buckets[hash_idx];
877 spin_lock(&tbl->hashwlock[hash_idx]);
878 hlist_for_each_entry(node, n, bucket, list) {
880 if (mpath->sdata == sdata &&
881 ether_addr_equal(addr, mpath->dst)) {
882 __mesh_path_del(tbl, node);
889 mesh_paths_generation++;
890 spin_unlock(&tbl->hashwlock[hash_idx]);
891 read_unlock_bh(&pathtbl_resize_lock);
896 * mesh_path_tx_pending - sends pending frames in a mesh path queue
898 * @mpath: mesh path to activate
900 * Locking: the state_lock of the mpath structure must NOT be held when calling
903 void mesh_path_tx_pending(struct mesh_path *mpath)
905 if (mpath->flags & MESH_PATH_ACTIVE)
906 ieee80211_add_pending_skbs(mpath->sdata->local,
907 &mpath->frame_queue);
911 * mesh_path_send_to_gates - sends pending frames to all known mesh gates
913 * @mpath: mesh path whose queue will be emptied
915 * If there is only one gate, the frames are transferred from the failed mpath
916 * queue to that gate's queue. If there are more than one gates, the frames
917 * are copied from each gate to the next. After frames are copied, the
918 * mpath queues are emptied onto the transmission queue.
920 int mesh_path_send_to_gates(struct mesh_path *mpath)
922 struct ieee80211_sub_if_data *sdata = mpath->sdata;
923 struct hlist_node *n;
924 struct mesh_table *tbl;
925 struct mesh_path *from_mpath = mpath;
926 struct mpath_node *gate = NULL;
928 struct hlist_head *known_gates;
931 tbl = rcu_dereference(mesh_paths);
932 known_gates = tbl->known_gates;
936 return -EHOSTUNREACH;
938 hlist_for_each_entry_rcu(gate, n, known_gates, list) {
939 if (gate->mpath->sdata != sdata)
942 if (gate->mpath->flags & MESH_PATH_ACTIVE) {
943 mpath_dbg(sdata, "Forwarding to %pM\n", gate->mpath->dst);
944 mesh_path_move_to_queue(gate->mpath, from_mpath, copy);
945 from_mpath = gate->mpath;
949 "Not forwarding %p (flags %#x)\n",
950 gate->mpath, gate->mpath->flags);
954 hlist_for_each_entry_rcu(gate, n, known_gates, list)
955 if (gate->mpath->sdata == sdata) {
956 mpath_dbg(sdata, "Sending to %pM\n", gate->mpath->dst);
957 mesh_path_tx_pending(gate->mpath);
960 return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
964 * mesh_path_discard_frame - discard a frame whose path could not be resolved
966 * @skb: frame to discard
967 * @sdata: network subif the frame was to be sent through
969 * Locking: the function must me called within a rcu_read_lock region
971 void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
975 sdata->u.mesh.mshstats.dropped_frames_no_route++;
979 * mesh_path_flush_pending - free the pending queue of a mesh path
981 * @mpath: mesh path whose queue has to be freed
983 * Locking: the function must me called within a rcu_read_lock region
985 void mesh_path_flush_pending(struct mesh_path *mpath)
989 while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL)
990 mesh_path_discard_frame(mpath->sdata, skb);
994 * mesh_path_fix_nexthop - force a specific next hop for a mesh path
996 * @mpath: the mesh path to modify
997 * @next_hop: the next hop to force
999 * Locking: this function must be called holding mpath->state_lock
1001 void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
1003 spin_lock_bh(&mpath->state_lock);
1004 mesh_path_assign_nexthop(mpath, next_hop);
1007 mpath->hop_count = 0;
1008 mpath->exp_time = 0;
1009 mpath->flags |= MESH_PATH_FIXED;
1010 mesh_path_activate(mpath);
1011 spin_unlock_bh(&mpath->state_lock);
1012 mesh_path_tx_pending(mpath);
1015 static void mesh_path_node_free(struct hlist_node *p, bool free_leafs)
1017 struct mesh_path *mpath;
1018 struct mpath_node *node = hlist_entry(p, struct mpath_node, list);
1019 mpath = node->mpath;
1022 del_timer_sync(&mpath->timer);
1028 static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
1030 struct mesh_path *mpath;
1031 struct mpath_node *node, *new_node;
1034 new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
1035 if (new_node == NULL)
1038 node = hlist_entry(p, struct mpath_node, list);
1039 mpath = node->mpath;
1040 new_node->mpath = mpath;
1041 hash_idx = mesh_table_hash(mpath->dst, mpath->sdata, newtbl);
1042 hlist_add_head(&new_node->list,
1043 &newtbl->hash_buckets[hash_idx]);
1047 int mesh_pathtbl_init(void)
1049 struct mesh_table *tbl_path, *tbl_mpp;
1052 tbl_path = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
1055 tbl_path->free_node = &mesh_path_node_free;
1056 tbl_path->copy_node = &mesh_path_node_copy;
1057 tbl_path->mean_chain_len = MEAN_CHAIN_LEN;
1058 tbl_path->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
1059 if (!tbl_path->known_gates) {
1063 INIT_HLIST_HEAD(tbl_path->known_gates);
1066 tbl_mpp = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
1071 tbl_mpp->free_node = &mesh_path_node_free;
1072 tbl_mpp->copy_node = &mesh_path_node_copy;
1073 tbl_mpp->mean_chain_len = MEAN_CHAIN_LEN;
1074 tbl_mpp->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
1075 if (!tbl_mpp->known_gates) {
1079 INIT_HLIST_HEAD(tbl_mpp->known_gates);
1081 /* Need no locking since this is during init */
1082 RCU_INIT_POINTER(mesh_paths, tbl_path);
1083 RCU_INIT_POINTER(mpp_paths, tbl_mpp);
1088 mesh_table_free(tbl_mpp, true);
1090 mesh_table_free(tbl_path, true);
1094 void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
1096 struct mesh_table *tbl;
1097 struct mesh_path *mpath;
1098 struct mpath_node *node;
1099 struct hlist_node *p;
1103 tbl = rcu_dereference(mesh_paths);
1104 for_each_mesh_entry(tbl, p, node, i) {
1105 if (node->mpath->sdata != sdata)
1107 mpath = node->mpath;
1108 if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
1109 (!(mpath->flags & MESH_PATH_FIXED)) &&
1110 time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
1111 mesh_path_del(mpath->sdata, mpath->dst);
1116 void mesh_pathtbl_unregister(void)
1118 /* no need for locking during exit path */
1119 mesh_table_free(rcu_dereference_protected(mesh_paths, 1), true);
1120 mesh_table_free(rcu_dereference_protected(mpp_paths, 1), true);