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743 lines
19 KiB
C
743 lines
19 KiB
C
/*
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* Copyright (c) 2008, 2009 open80211s Ltd.
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* Author: Luis Carlos Cobo <luisca@cozybit.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/etherdevice.h>
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#include <linux/list.h>
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#include <linux/random.h>
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#include <linux/spinlock.h>
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#include <linux/string.h>
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#include <net/mac80211.h>
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#include "ieee80211_i.h"
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#include "mesh.h"
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/* There will be initially 2^INIT_PATHS_SIZE_ORDER buckets */
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#define INIT_PATHS_SIZE_ORDER 2
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/* Keep the mean chain length below this constant */
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#define MEAN_CHAIN_LEN 2
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#define MPATH_EXPIRED(mpath) ((mpath->flags & MESH_PATH_ACTIVE) && \
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time_after(jiffies, mpath->exp_time) && \
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!(mpath->flags & MESH_PATH_FIXED))
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struct mpath_node {
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struct hlist_node list;
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struct rcu_head rcu;
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/* This indirection allows two different tables to point to the same
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* mesh_path structure, useful when resizing
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*/
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struct mesh_path *mpath;
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};
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static struct mesh_table *mesh_paths;
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static struct mesh_table *mpp_paths; /* Store paths for MPP&MAP */
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int mesh_paths_generation;
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static void __mesh_table_free(struct mesh_table *tbl)
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{
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kfree(tbl->hash_buckets);
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kfree(tbl->hashwlock);
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kfree(tbl);
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}
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void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
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{
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struct hlist_head *mesh_hash;
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struct hlist_node *p, *q;
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int i;
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mesh_hash = tbl->hash_buckets;
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for (i = 0; i <= tbl->hash_mask; i++) {
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spin_lock(&tbl->hashwlock[i]);
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hlist_for_each_safe(p, q, &mesh_hash[i]) {
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tbl->free_node(p, free_leafs);
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atomic_dec(&tbl->entries);
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}
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spin_unlock(&tbl->hashwlock[i]);
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}
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__mesh_table_free(tbl);
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}
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static struct mesh_table *mesh_table_grow(struct mesh_table *tbl)
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{
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struct mesh_table *newtbl;
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struct hlist_head *oldhash;
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struct hlist_node *p, *q;
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int i;
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if (atomic_read(&tbl->entries)
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< tbl->mean_chain_len * (tbl->hash_mask + 1))
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goto endgrow;
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newtbl = mesh_table_alloc(tbl->size_order + 1);
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if (!newtbl)
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goto endgrow;
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newtbl->free_node = tbl->free_node;
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newtbl->mean_chain_len = tbl->mean_chain_len;
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newtbl->copy_node = tbl->copy_node;
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atomic_set(&newtbl->entries, atomic_read(&tbl->entries));
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oldhash = tbl->hash_buckets;
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for (i = 0; i <= tbl->hash_mask; i++)
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hlist_for_each(p, &oldhash[i])
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if (tbl->copy_node(p, newtbl) < 0)
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goto errcopy;
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return newtbl;
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errcopy:
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for (i = 0; i <= newtbl->hash_mask; i++) {
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hlist_for_each_safe(p, q, &newtbl->hash_buckets[i])
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tbl->free_node(p, 0);
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}
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__mesh_table_free(newtbl);
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endgrow:
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return NULL;
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}
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/* This lock will have the grow table function as writer and add / delete nodes
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* as readers. When reading the table (i.e. doing lookups) we are well protected
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* by RCU
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*/
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static DEFINE_RWLOCK(pathtbl_resize_lock);
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/**
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*
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* mesh_path_assign_nexthop - update mesh path next hop
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*
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* @mpath: mesh path to update
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* @sta: next hop to assign
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*
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* Locking: mpath->state_lock must be held when calling this function
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*/
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void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
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{
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struct sk_buff *skb;
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struct ieee80211_hdr *hdr;
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struct sk_buff_head tmpq;
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unsigned long flags;
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rcu_assign_pointer(mpath->next_hop, sta);
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__skb_queue_head_init(&tmpq);
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spin_lock_irqsave(&mpath->frame_queue.lock, flags);
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while ((skb = __skb_dequeue(&mpath->frame_queue)) != NULL) {
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hdr = (struct ieee80211_hdr *) skb->data;
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memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
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__skb_queue_tail(&tmpq, skb);
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}
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skb_queue_splice(&tmpq, &mpath->frame_queue);
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spin_unlock_irqrestore(&mpath->frame_queue.lock, flags);
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}
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/**
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* mesh_path_lookup - look up a path in the mesh path table
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* @dst: hardware address (ETH_ALEN length) of destination
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* @sdata: local subif
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*
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* Returns: pointer to the mesh path structure, or NULL if not found
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*
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* Locking: must be called within a read rcu section.
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*/
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struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
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{
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struct mesh_path *mpath;
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struct hlist_node *n;
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struct hlist_head *bucket;
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struct mesh_table *tbl;
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struct mpath_node *node;
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tbl = rcu_dereference(mesh_paths);
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bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
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hlist_for_each_entry_rcu(node, n, bucket, list) {
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mpath = node->mpath;
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if (mpath->sdata == sdata &&
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memcmp(dst, mpath->dst, ETH_ALEN) == 0) {
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if (MPATH_EXPIRED(mpath)) {
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spin_lock_bh(&mpath->state_lock);
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if (MPATH_EXPIRED(mpath))
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mpath->flags &= ~MESH_PATH_ACTIVE;
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spin_unlock_bh(&mpath->state_lock);
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}
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return mpath;
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}
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}
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return NULL;
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}
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struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
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{
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struct mesh_path *mpath;
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struct hlist_node *n;
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struct hlist_head *bucket;
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struct mesh_table *tbl;
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struct mpath_node *node;
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tbl = rcu_dereference(mpp_paths);
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bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
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hlist_for_each_entry_rcu(node, n, bucket, list) {
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mpath = node->mpath;
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if (mpath->sdata == sdata &&
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memcmp(dst, mpath->dst, ETH_ALEN) == 0) {
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if (MPATH_EXPIRED(mpath)) {
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spin_lock_bh(&mpath->state_lock);
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if (MPATH_EXPIRED(mpath))
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mpath->flags &= ~MESH_PATH_ACTIVE;
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spin_unlock_bh(&mpath->state_lock);
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}
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return mpath;
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}
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}
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return NULL;
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}
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/**
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* mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
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* @idx: index
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* @sdata: local subif, or NULL for all entries
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*
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* Returns: pointer to the mesh path structure, or NULL if not found.
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*
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* Locking: must be called within a read rcu section.
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*/
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struct mesh_path *mesh_path_lookup_by_idx(int idx, struct ieee80211_sub_if_data *sdata)
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{
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struct mpath_node *node;
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struct hlist_node *p;
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int i;
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int j = 0;
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for_each_mesh_entry(mesh_paths, p, node, i) {
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if (sdata && node->mpath->sdata != sdata)
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continue;
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if (j++ == idx) {
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if (MPATH_EXPIRED(node->mpath)) {
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spin_lock_bh(&node->mpath->state_lock);
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if (MPATH_EXPIRED(node->mpath))
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node->mpath->flags &= ~MESH_PATH_ACTIVE;
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spin_unlock_bh(&node->mpath->state_lock);
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}
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return node->mpath;
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}
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}
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return NULL;
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}
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/**
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* mesh_path_add - allocate and add a new path to the mesh path table
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* @addr: destination address of the path (ETH_ALEN length)
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* @sdata: local subif
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*
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* Returns: 0 on success
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*
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* State: the initial state of the new path is set to 0
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*/
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int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
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{
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struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
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struct ieee80211_local *local = sdata->local;
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struct mesh_path *mpath, *new_mpath;
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struct mpath_node *node, *new_node;
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struct hlist_head *bucket;
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struct hlist_node *n;
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int grow = 0;
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int err = 0;
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u32 hash_idx;
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if (memcmp(dst, sdata->vif.addr, ETH_ALEN) == 0)
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/* never add ourselves as neighbours */
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return -ENOTSUPP;
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if (is_multicast_ether_addr(dst))
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return -ENOTSUPP;
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if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
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return -ENOSPC;
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err = -ENOMEM;
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new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
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if (!new_mpath)
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goto err_path_alloc;
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new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
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if (!new_node)
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goto err_node_alloc;
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read_lock(&pathtbl_resize_lock);
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memcpy(new_mpath->dst, dst, ETH_ALEN);
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new_mpath->sdata = sdata;
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new_mpath->flags = 0;
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skb_queue_head_init(&new_mpath->frame_queue);
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new_node->mpath = new_mpath;
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new_mpath->timer.data = (unsigned long) new_mpath;
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new_mpath->timer.function = mesh_path_timer;
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new_mpath->exp_time = jiffies;
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spin_lock_init(&new_mpath->state_lock);
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init_timer(&new_mpath->timer);
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hash_idx = mesh_table_hash(dst, sdata, mesh_paths);
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bucket = &mesh_paths->hash_buckets[hash_idx];
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spin_lock(&mesh_paths->hashwlock[hash_idx]);
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err = -EEXIST;
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hlist_for_each_entry(node, n, bucket, list) {
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mpath = node->mpath;
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if (mpath->sdata == sdata && memcmp(dst, mpath->dst, ETH_ALEN) == 0)
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goto err_exists;
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}
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hlist_add_head_rcu(&new_node->list, bucket);
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if (atomic_inc_return(&mesh_paths->entries) >=
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mesh_paths->mean_chain_len * (mesh_paths->hash_mask + 1))
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grow = 1;
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mesh_paths_generation++;
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spin_unlock(&mesh_paths->hashwlock[hash_idx]);
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read_unlock(&pathtbl_resize_lock);
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if (grow) {
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set_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags);
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ieee80211_queue_work(&local->hw, &ifmsh->work);
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}
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return 0;
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err_exists:
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spin_unlock(&mesh_paths->hashwlock[hash_idx]);
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read_unlock(&pathtbl_resize_lock);
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kfree(new_node);
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err_node_alloc:
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kfree(new_mpath);
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err_path_alloc:
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atomic_dec(&sdata->u.mesh.mpaths);
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return err;
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}
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void mesh_mpath_table_grow(void)
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{
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struct mesh_table *oldtbl, *newtbl;
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write_lock(&pathtbl_resize_lock);
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oldtbl = mesh_paths;
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newtbl = mesh_table_grow(mesh_paths);
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if (!newtbl) {
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write_unlock(&pathtbl_resize_lock);
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return;
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}
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rcu_assign_pointer(mesh_paths, newtbl);
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write_unlock(&pathtbl_resize_lock);
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synchronize_rcu();
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mesh_table_free(oldtbl, false);
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}
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void mesh_mpp_table_grow(void)
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{
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struct mesh_table *oldtbl, *newtbl;
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write_lock(&pathtbl_resize_lock);
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oldtbl = mpp_paths;
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newtbl = mesh_table_grow(mpp_paths);
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if (!newtbl) {
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write_unlock(&pathtbl_resize_lock);
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return;
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}
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rcu_assign_pointer(mpp_paths, newtbl);
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write_unlock(&pathtbl_resize_lock);
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synchronize_rcu();
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mesh_table_free(oldtbl, false);
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}
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int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
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{
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struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
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struct ieee80211_local *local = sdata->local;
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struct mesh_path *mpath, *new_mpath;
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struct mpath_node *node, *new_node;
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struct hlist_head *bucket;
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struct hlist_node *n;
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int grow = 0;
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int err = 0;
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u32 hash_idx;
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if (memcmp(dst, sdata->vif.addr, ETH_ALEN) == 0)
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/* never add ourselves as neighbours */
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return -ENOTSUPP;
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if (is_multicast_ether_addr(dst))
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return -ENOTSUPP;
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err = -ENOMEM;
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new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
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if (!new_mpath)
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goto err_path_alloc;
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new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
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if (!new_node)
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goto err_node_alloc;
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read_lock(&pathtbl_resize_lock);
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memcpy(new_mpath->dst, dst, ETH_ALEN);
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memcpy(new_mpath->mpp, mpp, ETH_ALEN);
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new_mpath->sdata = sdata;
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new_mpath->flags = 0;
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skb_queue_head_init(&new_mpath->frame_queue);
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new_node->mpath = new_mpath;
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new_mpath->exp_time = jiffies;
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spin_lock_init(&new_mpath->state_lock);
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hash_idx = mesh_table_hash(dst, sdata, mpp_paths);
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bucket = &mpp_paths->hash_buckets[hash_idx];
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spin_lock(&mpp_paths->hashwlock[hash_idx]);
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err = -EEXIST;
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hlist_for_each_entry(node, n, bucket, list) {
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mpath = node->mpath;
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if (mpath->sdata == sdata && memcmp(dst, mpath->dst, ETH_ALEN) == 0)
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goto err_exists;
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}
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hlist_add_head_rcu(&new_node->list, bucket);
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if (atomic_inc_return(&mpp_paths->entries) >=
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mpp_paths->mean_chain_len * (mpp_paths->hash_mask + 1))
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grow = 1;
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spin_unlock(&mpp_paths->hashwlock[hash_idx]);
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read_unlock(&pathtbl_resize_lock);
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if (grow) {
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set_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags);
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ieee80211_queue_work(&local->hw, &ifmsh->work);
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}
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return 0;
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err_exists:
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spin_unlock(&mpp_paths->hashwlock[hash_idx]);
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read_unlock(&pathtbl_resize_lock);
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kfree(new_node);
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err_node_alloc:
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kfree(new_mpath);
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err_path_alloc:
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return err;
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}
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/**
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* mesh_plink_broken - deactivates paths and sends perr when a link breaks
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*
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* @sta: broken peer link
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*
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* This function must be called from the rate control algorithm if enough
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* delivery errors suggest that a peer link is no longer usable.
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*/
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void mesh_plink_broken(struct sta_info *sta)
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{
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static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
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struct mesh_path *mpath;
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struct mpath_node *node;
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struct hlist_node *p;
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struct ieee80211_sub_if_data *sdata = sta->sdata;
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int i;
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rcu_read_lock();
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for_each_mesh_entry(mesh_paths, p, node, i) {
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mpath = node->mpath;
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spin_lock_bh(&mpath->state_lock);
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if (mpath->next_hop == sta &&
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mpath->flags & MESH_PATH_ACTIVE &&
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!(mpath->flags & MESH_PATH_FIXED)) {
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mpath->flags &= ~MESH_PATH_ACTIVE;
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++mpath->sn;
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spin_unlock_bh(&mpath->state_lock);
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mesh_path_error_tx(MESH_TTL, mpath->dst,
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cpu_to_le32(mpath->sn),
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cpu_to_le16(PERR_RCODE_DEST_UNREACH),
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bcast, sdata);
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} else
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spin_unlock_bh(&mpath->state_lock);
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}
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rcu_read_unlock();
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}
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|
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/**
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* mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
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*
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* @sta - mesh peer to match
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*
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* RCU notes: this function is called when a mesh plink transitions from
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* PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
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* allows path creation. This will happen before the sta can be freed (because
|
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* sta_info_destroy() calls this) so any reader in a rcu read block will be
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* protected against the plink disappearing.
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*/
|
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void mesh_path_flush_by_nexthop(struct sta_info *sta)
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{
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struct mesh_path *mpath;
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struct mpath_node *node;
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struct hlist_node *p;
|
|
int i;
|
|
|
|
for_each_mesh_entry(mesh_paths, p, node, i) {
|
|
mpath = node->mpath;
|
|
if (mpath->next_hop == sta)
|
|
mesh_path_del(mpath->dst, mpath->sdata);
|
|
}
|
|
}
|
|
|
|
void mesh_path_flush(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_node *p;
|
|
int i;
|
|
|
|
for_each_mesh_entry(mesh_paths, p, node, i) {
|
|
mpath = node->mpath;
|
|
if (mpath->sdata == sdata)
|
|
mesh_path_del(mpath->dst, mpath->sdata);
|
|
}
|
|
}
|
|
|
|
static void mesh_path_node_reclaim(struct rcu_head *rp)
|
|
{
|
|
struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
|
|
struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
|
|
|
|
del_timer_sync(&node->mpath->timer);
|
|
atomic_dec(&sdata->u.mesh.mpaths);
|
|
kfree(node->mpath);
|
|
kfree(node);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_del - delete a mesh path from the table
|
|
*
|
|
* @addr: dst address (ETH_ALEN length)
|
|
* @sdata: local subif
|
|
*
|
|
* Returns: 0 if successful
|
|
*/
|
|
int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_head *bucket;
|
|
struct hlist_node *n;
|
|
int hash_idx;
|
|
int err = 0;
|
|
|
|
read_lock(&pathtbl_resize_lock);
|
|
hash_idx = mesh_table_hash(addr, sdata, mesh_paths);
|
|
bucket = &mesh_paths->hash_buckets[hash_idx];
|
|
|
|
spin_lock(&mesh_paths->hashwlock[hash_idx]);
|
|
hlist_for_each_entry(node, n, bucket, list) {
|
|
mpath = node->mpath;
|
|
if (mpath->sdata == sdata &&
|
|
memcmp(addr, mpath->dst, ETH_ALEN) == 0) {
|
|
spin_lock_bh(&mpath->state_lock);
|
|
mpath->flags |= MESH_PATH_RESOLVING;
|
|
hlist_del_rcu(&node->list);
|
|
call_rcu(&node->rcu, mesh_path_node_reclaim);
|
|
atomic_dec(&mesh_paths->entries);
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
goto enddel;
|
|
}
|
|
}
|
|
|
|
err = -ENXIO;
|
|
enddel:
|
|
mesh_paths_generation++;
|
|
spin_unlock(&mesh_paths->hashwlock[hash_idx]);
|
|
read_unlock(&pathtbl_resize_lock);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* mesh_path_tx_pending - sends pending frames in a mesh path queue
|
|
*
|
|
* @mpath: mesh path to activate
|
|
*
|
|
* Locking: the state_lock of the mpath structure must NOT be held when calling
|
|
* this function.
|
|
*/
|
|
void mesh_path_tx_pending(struct mesh_path *mpath)
|
|
{
|
|
if (mpath->flags & MESH_PATH_ACTIVE)
|
|
ieee80211_add_pending_skbs(mpath->sdata->local,
|
|
&mpath->frame_queue);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_discard_frame - discard a frame whose path could not be resolved
|
|
*
|
|
* @skb: frame to discard
|
|
* @sdata: network subif the frame was to be sent through
|
|
*
|
|
* If the frame was being forwarded from another MP, a PERR frame will be sent
|
|
* to the precursor. The precursor's address (i.e. the previous hop) was saved
|
|
* in addr1 of the frame-to-be-forwarded, and would only be overwritten once
|
|
* the destination is successfully resolved.
|
|
*
|
|
* Locking: the function must me called within a rcu_read_lock region
|
|
*/
|
|
void mesh_path_discard_frame(struct sk_buff *skb,
|
|
struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
|
|
struct mesh_path *mpath;
|
|
u32 sn = 0;
|
|
|
|
if (memcmp(hdr->addr4, sdata->vif.addr, ETH_ALEN) != 0) {
|
|
u8 *ra, *da;
|
|
|
|
da = hdr->addr3;
|
|
ra = hdr->addr1;
|
|
mpath = mesh_path_lookup(da, sdata);
|
|
if (mpath)
|
|
sn = ++mpath->sn;
|
|
mesh_path_error_tx(MESH_TTL, skb->data, cpu_to_le32(sn),
|
|
cpu_to_le16(PERR_RCODE_NO_ROUTE), ra, sdata);
|
|
}
|
|
|
|
kfree_skb(skb);
|
|
sdata->u.mesh.mshstats.dropped_frames_no_route++;
|
|
}
|
|
|
|
/**
|
|
* mesh_path_flush_pending - free the pending queue of a mesh path
|
|
*
|
|
* @mpath: mesh path whose queue has to be freed
|
|
*
|
|
* Locking: the function must me called withing a rcu_read_lock region
|
|
*/
|
|
void mesh_path_flush_pending(struct mesh_path *mpath)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
while ((skb = skb_dequeue(&mpath->frame_queue)) &&
|
|
(mpath->flags & MESH_PATH_ACTIVE))
|
|
mesh_path_discard_frame(skb, mpath->sdata);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_fix_nexthop - force a specific next hop for a mesh path
|
|
*
|
|
* @mpath: the mesh path to modify
|
|
* @next_hop: the next hop to force
|
|
*
|
|
* Locking: this function must be called holding mpath->state_lock
|
|
*/
|
|
void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
|
|
{
|
|
spin_lock_bh(&mpath->state_lock);
|
|
mesh_path_assign_nexthop(mpath, next_hop);
|
|
mpath->sn = 0xffff;
|
|
mpath->metric = 0;
|
|
mpath->hop_count = 0;
|
|
mpath->exp_time = 0;
|
|
mpath->flags |= MESH_PATH_FIXED;
|
|
mesh_path_activate(mpath);
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
mesh_path_tx_pending(mpath);
|
|
}
|
|
|
|
static void mesh_path_node_free(struct hlist_node *p, bool free_leafs)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node = hlist_entry(p, struct mpath_node, list);
|
|
mpath = node->mpath;
|
|
hlist_del_rcu(p);
|
|
if (free_leafs)
|
|
kfree(mpath);
|
|
kfree(node);
|
|
}
|
|
|
|
static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node, *new_node;
|
|
u32 hash_idx;
|
|
|
|
new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
|
|
if (new_node == NULL)
|
|
return -ENOMEM;
|
|
|
|
node = hlist_entry(p, struct mpath_node, list);
|
|
mpath = node->mpath;
|
|
new_node->mpath = mpath;
|
|
hash_idx = mesh_table_hash(mpath->dst, mpath->sdata, newtbl);
|
|
hlist_add_head(&new_node->list,
|
|
&newtbl->hash_buckets[hash_idx]);
|
|
return 0;
|
|
}
|
|
|
|
int mesh_pathtbl_init(void)
|
|
{
|
|
mesh_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
|
|
if (!mesh_paths)
|
|
return -ENOMEM;
|
|
mesh_paths->free_node = &mesh_path_node_free;
|
|
mesh_paths->copy_node = &mesh_path_node_copy;
|
|
mesh_paths->mean_chain_len = MEAN_CHAIN_LEN;
|
|
|
|
mpp_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
|
|
if (!mpp_paths) {
|
|
mesh_table_free(mesh_paths, true);
|
|
return -ENOMEM;
|
|
}
|
|
mpp_paths->free_node = &mesh_path_node_free;
|
|
mpp_paths->copy_node = &mesh_path_node_copy;
|
|
mpp_paths->mean_chain_len = MEAN_CHAIN_LEN;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_node *p;
|
|
int i;
|
|
|
|
read_lock(&pathtbl_resize_lock);
|
|
for_each_mesh_entry(mesh_paths, p, node, i) {
|
|
if (node->mpath->sdata != sdata)
|
|
continue;
|
|
mpath = node->mpath;
|
|
spin_lock_bh(&mpath->state_lock);
|
|
if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
|
|
(!(mpath->flags & MESH_PATH_FIXED)) &&
|
|
time_after(jiffies,
|
|
mpath->exp_time + MESH_PATH_EXPIRE)) {
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
mesh_path_del(mpath->dst, mpath->sdata);
|
|
} else
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
}
|
|
read_unlock(&pathtbl_resize_lock);
|
|
}
|
|
|
|
void mesh_pathtbl_unregister(void)
|
|
{
|
|
mesh_table_free(mesh_paths, true);
|
|
mesh_table_free(mpp_paths, true);
|
|
}
|