![Thomas Pedersen](/assets/img/avatar_default.png)
Use skb_queue_walk_safe instead, and fix a few issues: - didn't free old skbs on moving - didn't react to failed skb alloc - needlessly held a local pointer to the destination frame queue - didn't check destination queue length before adding skb Signed-off-by: Thomas Pedersen <thomas@cozybit.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
1117 lines
29 KiB
C
1117 lines
29 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/slab.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 "wme.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 __rcu *mesh_paths;
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static struct mesh_table __rcu *mpp_paths; /* Store paths for MPP&MAP */
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int mesh_paths_generation;
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/* This lock will have the grow table function as writer and add / delete nodes
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* as readers. RCU provides sufficient protection only when reading the table
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* (i.e. doing lookups). Adding or adding or removing nodes requires we take
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* the read lock or we risk operating on an old table. The write lock is only
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* needed when modifying the number of buckets a table.
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*/
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static DEFINE_RWLOCK(pathtbl_resize_lock);
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static inline struct mesh_table *resize_dereference_mesh_paths(void)
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{
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return rcu_dereference_protected(mesh_paths,
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lockdep_is_held(&pathtbl_resize_lock));
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}
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static inline struct mesh_table *resize_dereference_mpp_paths(void)
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{
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return rcu_dereference_protected(mpp_paths,
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lockdep_is_held(&pathtbl_resize_lock));
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}
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/*
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* CAREFUL -- "tbl" must not be an expression,
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* in particular not an rcu_dereference(), since
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* it's used twice. So it is illegal to do
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* for_each_mesh_entry(rcu_dereference(...), ...)
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*/
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#define for_each_mesh_entry(tbl, p, node, i) \
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for (i = 0; i <= tbl->hash_mask; i++) \
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hlist_for_each_entry_rcu(node, p, &tbl->hash_buckets[i], list)
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static struct mesh_table *mesh_table_alloc(int size_order)
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{
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int i;
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struct mesh_table *newtbl;
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newtbl = kmalloc(sizeof(struct mesh_table), GFP_ATOMIC);
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if (!newtbl)
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return NULL;
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newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
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(1 << size_order), GFP_ATOMIC);
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if (!newtbl->hash_buckets) {
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kfree(newtbl);
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return NULL;
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}
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newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
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(1 << size_order), GFP_ATOMIC);
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if (!newtbl->hashwlock) {
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kfree(newtbl->hash_buckets);
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kfree(newtbl);
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return NULL;
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}
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newtbl->size_order = size_order;
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newtbl->hash_mask = (1 << size_order) - 1;
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atomic_set(&newtbl->entries, 0);
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get_random_bytes(&newtbl->hash_rnd,
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sizeof(newtbl->hash_rnd));
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for (i = 0; i <= newtbl->hash_mask; i++)
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spin_lock_init(&newtbl->hashwlock[i]);
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spin_lock_init(&newtbl->gates_lock);
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return newtbl;
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}
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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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static 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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struct mpath_node *gate;
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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_bh(&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_bh(&tbl->hashwlock[i]);
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}
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if (free_leafs) {
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spin_lock_bh(&tbl->gates_lock);
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hlist_for_each_entry_safe(gate, p, q,
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tbl->known_gates, list) {
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hlist_del(&gate->list);
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kfree(gate);
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}
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kfree(tbl->known_gates);
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spin_unlock_bh(&tbl->gates_lock);
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}
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__mesh_table_free(tbl);
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}
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static int mesh_table_grow(struct mesh_table *oldtbl,
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struct mesh_table *newtbl)
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{
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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(&oldtbl->entries)
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< oldtbl->mean_chain_len * (oldtbl->hash_mask + 1))
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return -EAGAIN;
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newtbl->free_node = oldtbl->free_node;
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newtbl->mean_chain_len = oldtbl->mean_chain_len;
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newtbl->copy_node = oldtbl->copy_node;
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newtbl->known_gates = oldtbl->known_gates;
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atomic_set(&newtbl->entries, atomic_read(&oldtbl->entries));
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oldhash = oldtbl->hash_buckets;
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for (i = 0; i <= oldtbl->hash_mask; i++)
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hlist_for_each(p, &oldhash[i])
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if (oldtbl->copy_node(p, newtbl) < 0)
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goto errcopy;
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return 0;
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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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oldtbl->free_node(p, 0);
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}
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return -ENOMEM;
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}
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static u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata,
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struct mesh_table *tbl)
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{
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/* Use last four bytes of hw addr and interface index as hash index */
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return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex, tbl->hash_rnd)
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& tbl->hash_mask;
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}
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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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unsigned long flags;
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rcu_assign_pointer(mpath->next_hop, sta);
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spin_lock_irqsave(&mpath->frame_queue.lock, flags);
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skb_queue_walk(&mpath->frame_queue, skb) {
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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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memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
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}
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spin_unlock_irqrestore(&mpath->frame_queue.lock, flags);
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}
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static void prepare_for_gate(struct sk_buff *skb, char *dst_addr,
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struct mesh_path *gate_mpath)
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{
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struct ieee80211_hdr *hdr;
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struct ieee80211s_hdr *mshdr;
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int mesh_hdrlen, hdrlen;
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char *next_hop;
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hdr = (struct ieee80211_hdr *) skb->data;
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hdrlen = ieee80211_hdrlen(hdr->frame_control);
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mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
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if (!(mshdr->flags & MESH_FLAGS_AE)) {
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/* size of the fixed part of the mesh header */
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mesh_hdrlen = 6;
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/* make room for the two extended addresses */
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skb_push(skb, 2 * ETH_ALEN);
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memmove(skb->data, hdr, hdrlen + mesh_hdrlen);
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hdr = (struct ieee80211_hdr *) skb->data;
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/* we preserve the previous mesh header and only add
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* the new addreses */
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mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
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mshdr->flags = MESH_FLAGS_AE_A5_A6;
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memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN);
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memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN);
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}
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/* update next hop */
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hdr = (struct ieee80211_hdr *) skb->data;
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rcu_read_lock();
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next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr;
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memcpy(hdr->addr1, next_hop, ETH_ALEN);
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rcu_read_unlock();
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memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN);
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memcpy(hdr->addr3, dst_addr, ETH_ALEN);
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}
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/**
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*
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* mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
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*
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* This function is used to transfer or copy frames from an unresolved mpath to
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* a gate mpath. The function also adds the Address Extension field and
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* updates the next hop.
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*
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* If a frame already has an Address Extension field, only the next hop and
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* destination addresses are updated.
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*
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* The gate mpath must be an active mpath with a valid mpath->next_hop.
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*
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* @mpath: An active mpath the frames will be sent to (i.e. the gate)
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* @from_mpath: The failed mpath
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* @copy: When true, copy all the frames to the new mpath queue. When false,
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* move them.
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*/
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static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
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struct mesh_path *from_mpath,
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bool copy)
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{
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struct sk_buff *skb, *fskb, *tmp;
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struct sk_buff_head failq;
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unsigned long flags;
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BUG_ON(gate_mpath == from_mpath);
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BUG_ON(!gate_mpath->next_hop);
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__skb_queue_head_init(&failq);
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spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
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skb_queue_splice_init(&from_mpath->frame_queue, &failq);
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spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
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skb_queue_walk_safe(&failq, fskb, tmp) {
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if (skb_queue_len(&gate_mpath->frame_queue) >=
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MESH_FRAME_QUEUE_LEN) {
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mpath_dbg(gate_mpath->sdata, "mpath queue full!\n");
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break;
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}
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skb = skb_copy(fskb, GFP_ATOMIC);
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if (WARN_ON(!skb))
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break;
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prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
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skb_queue_tail(&gate_mpath->frame_queue, skb);
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if (copy)
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continue;
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__skb_unlink(fskb, &failq);
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kfree_skb(fskb);
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}
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mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n",
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gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue));
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if (!copy)
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return;
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spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
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skb_queue_splice(&failq, &from_mpath->frame_queue);
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spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
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}
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static struct mesh_path *mpath_lookup(struct mesh_table *tbl, u8 *dst,
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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 mpath_node *node;
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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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ether_addr_equal(dst, mpath->dst)) {
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if (MPATH_EXPIRED(mpath)) {
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spin_lock_bh(&mpath->state_lock);
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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 - 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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return mpath_lookup(rcu_dereference(mesh_paths), dst, sdata);
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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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return mpath_lookup(rcu_dereference(mpp_paths), dst, sdata);
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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 mesh_table *tbl = rcu_dereference(mesh_paths);
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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(tbl, 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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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_gate - add the given mpath to a mesh gate to our path table
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* @mpath: gate path to add to table
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*/
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int mesh_path_add_gate(struct mesh_path *mpath)
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{
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struct mesh_table *tbl;
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struct mpath_node *gate, *new_gate;
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struct hlist_node *n;
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int err;
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rcu_read_lock();
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tbl = rcu_dereference(mesh_paths);
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hlist_for_each_entry_rcu(gate, n, tbl->known_gates, list)
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if (gate->mpath == mpath) {
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err = -EEXIST;
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goto err_rcu;
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}
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new_gate = kzalloc(sizeof(struct mpath_node), GFP_ATOMIC);
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if (!new_gate) {
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err = -ENOMEM;
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goto err_rcu;
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}
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mpath->is_gate = true;
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mpath->sdata->u.mesh.num_gates++;
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new_gate->mpath = mpath;
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spin_lock_bh(&tbl->gates_lock);
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hlist_add_head_rcu(&new_gate->list, tbl->known_gates);
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spin_unlock_bh(&tbl->gates_lock);
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rcu_read_unlock();
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mpath_dbg(mpath->sdata,
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"Mesh path: Recorded new gate: %pM. %d known gates\n",
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mpath->dst, mpath->sdata->u.mesh.num_gates);
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return 0;
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err_rcu:
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rcu_read_unlock();
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return err;
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}
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/**
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* mesh_gate_del - remove a mesh gate from the list of known gates
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* @tbl: table which holds our list of known gates
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* @mpath: gate mpath
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*
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* Returns: 0 on success
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*
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* Locking: must be called inside rcu_read_lock() section
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*/
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static int mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
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{
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struct mpath_node *gate;
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struct hlist_node *p, *q;
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hlist_for_each_entry_safe(gate, p, q, tbl->known_gates, list)
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if (gate->mpath == mpath) {
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spin_lock_bh(&tbl->gates_lock);
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hlist_del_rcu(&gate->list);
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kfree_rcu(gate, rcu);
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spin_unlock_bh(&tbl->gates_lock);
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mpath->sdata->u.mesh.num_gates--;
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mpath->is_gate = false;
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mpath_dbg(mpath->sdata,
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"Mesh path: Deleted gate: %pM. %d known gates\n",
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mpath->dst, mpath->sdata->u.mesh.num_gates);
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break;
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}
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return 0;
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}
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/**
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* mesh_gate_num - number of gates known to this interface
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* @sdata: subif data
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*/
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int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
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{
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return sdata->u.mesh.num_gates;
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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
|
|
* @addr: destination address of the path (ETH_ALEN length)
|
|
* @sdata: local subif
|
|
*
|
|
* Returns: 0 on success
|
|
*
|
|
* State: the initial state of the new path is set to 0
|
|
*/
|
|
int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
|
|
struct ieee80211_local *local = sdata->local;
|
|
struct mesh_table *tbl;
|
|
struct mesh_path *mpath, *new_mpath;
|
|
struct mpath_node *node, *new_node;
|
|
struct hlist_head *bucket;
|
|
struct hlist_node *n;
|
|
int grow = 0;
|
|
int err = 0;
|
|
u32 hash_idx;
|
|
|
|
if (ether_addr_equal(dst, sdata->vif.addr))
|
|
/* never add ourselves as neighbours */
|
|
return -ENOTSUPP;
|
|
|
|
if (is_multicast_ether_addr(dst))
|
|
return -ENOTSUPP;
|
|
|
|
if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
|
|
return -ENOSPC;
|
|
|
|
err = -ENOMEM;
|
|
new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
|
|
if (!new_mpath)
|
|
goto err_path_alloc;
|
|
|
|
new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
|
|
if (!new_node)
|
|
goto err_node_alloc;
|
|
|
|
read_lock_bh(&pathtbl_resize_lock);
|
|
memcpy(new_mpath->dst, dst, ETH_ALEN);
|
|
eth_broadcast_addr(new_mpath->rann_snd_addr);
|
|
new_mpath->is_root = false;
|
|
new_mpath->sdata = sdata;
|
|
new_mpath->flags = 0;
|
|
skb_queue_head_init(&new_mpath->frame_queue);
|
|
new_node->mpath = new_mpath;
|
|
new_mpath->timer.data = (unsigned long) new_mpath;
|
|
new_mpath->timer.function = mesh_path_timer;
|
|
new_mpath->exp_time = jiffies;
|
|
spin_lock_init(&new_mpath->state_lock);
|
|
init_timer(&new_mpath->timer);
|
|
|
|
tbl = resize_dereference_mesh_paths();
|
|
|
|
hash_idx = mesh_table_hash(dst, sdata, tbl);
|
|
bucket = &tbl->hash_buckets[hash_idx];
|
|
|
|
spin_lock(&tbl->hashwlock[hash_idx]);
|
|
|
|
err = -EEXIST;
|
|
hlist_for_each_entry(node, n, bucket, list) {
|
|
mpath = node->mpath;
|
|
if (mpath->sdata == sdata &&
|
|
ether_addr_equal(dst, mpath->dst))
|
|
goto err_exists;
|
|
}
|
|
|
|
hlist_add_head_rcu(&new_node->list, bucket);
|
|
if (atomic_inc_return(&tbl->entries) >=
|
|
tbl->mean_chain_len * (tbl->hash_mask + 1))
|
|
grow = 1;
|
|
|
|
mesh_paths_generation++;
|
|
|
|
spin_unlock(&tbl->hashwlock[hash_idx]);
|
|
read_unlock_bh(&pathtbl_resize_lock);
|
|
if (grow) {
|
|
set_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags);
|
|
ieee80211_queue_work(&local->hw, &sdata->work);
|
|
}
|
|
return 0;
|
|
|
|
err_exists:
|
|
spin_unlock(&tbl->hashwlock[hash_idx]);
|
|
read_unlock_bh(&pathtbl_resize_lock);
|
|
kfree(new_node);
|
|
err_node_alloc:
|
|
kfree(new_mpath);
|
|
err_path_alloc:
|
|
atomic_dec(&sdata->u.mesh.mpaths);
|
|
return err;
|
|
}
|
|
|
|
static void mesh_table_free_rcu(struct rcu_head *rcu)
|
|
{
|
|
struct mesh_table *tbl = container_of(rcu, struct mesh_table, rcu_head);
|
|
|
|
mesh_table_free(tbl, false);
|
|
}
|
|
|
|
void mesh_mpath_table_grow(void)
|
|
{
|
|
struct mesh_table *oldtbl, *newtbl;
|
|
|
|
write_lock_bh(&pathtbl_resize_lock);
|
|
oldtbl = resize_dereference_mesh_paths();
|
|
newtbl = mesh_table_alloc(oldtbl->size_order + 1);
|
|
if (!newtbl)
|
|
goto out;
|
|
if (mesh_table_grow(oldtbl, newtbl) < 0) {
|
|
__mesh_table_free(newtbl);
|
|
goto out;
|
|
}
|
|
rcu_assign_pointer(mesh_paths, newtbl);
|
|
|
|
call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
|
|
|
|
out:
|
|
write_unlock_bh(&pathtbl_resize_lock);
|
|
}
|
|
|
|
void mesh_mpp_table_grow(void)
|
|
{
|
|
struct mesh_table *oldtbl, *newtbl;
|
|
|
|
write_lock_bh(&pathtbl_resize_lock);
|
|
oldtbl = resize_dereference_mpp_paths();
|
|
newtbl = mesh_table_alloc(oldtbl->size_order + 1);
|
|
if (!newtbl)
|
|
goto out;
|
|
if (mesh_table_grow(oldtbl, newtbl) < 0) {
|
|
__mesh_table_free(newtbl);
|
|
goto out;
|
|
}
|
|
rcu_assign_pointer(mpp_paths, newtbl);
|
|
call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
|
|
|
|
out:
|
|
write_unlock_bh(&pathtbl_resize_lock);
|
|
}
|
|
|
|
int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
|
|
struct ieee80211_local *local = sdata->local;
|
|
struct mesh_table *tbl;
|
|
struct mesh_path *mpath, *new_mpath;
|
|
struct mpath_node *node, *new_node;
|
|
struct hlist_head *bucket;
|
|
struct hlist_node *n;
|
|
int grow = 0;
|
|
int err = 0;
|
|
u32 hash_idx;
|
|
|
|
if (ether_addr_equal(dst, sdata->vif.addr))
|
|
/* never add ourselves as neighbours */
|
|
return -ENOTSUPP;
|
|
|
|
if (is_multicast_ether_addr(dst))
|
|
return -ENOTSUPP;
|
|
|
|
err = -ENOMEM;
|
|
new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
|
|
if (!new_mpath)
|
|
goto err_path_alloc;
|
|
|
|
new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
|
|
if (!new_node)
|
|
goto err_node_alloc;
|
|
|
|
read_lock_bh(&pathtbl_resize_lock);
|
|
memcpy(new_mpath->dst, dst, ETH_ALEN);
|
|
memcpy(new_mpath->mpp, mpp, ETH_ALEN);
|
|
new_mpath->sdata = sdata;
|
|
new_mpath->flags = 0;
|
|
skb_queue_head_init(&new_mpath->frame_queue);
|
|
new_node->mpath = new_mpath;
|
|
init_timer(&new_mpath->timer);
|
|
new_mpath->exp_time = jiffies;
|
|
spin_lock_init(&new_mpath->state_lock);
|
|
|
|
tbl = resize_dereference_mpp_paths();
|
|
|
|
hash_idx = mesh_table_hash(dst, sdata, tbl);
|
|
bucket = &tbl->hash_buckets[hash_idx];
|
|
|
|
spin_lock(&tbl->hashwlock[hash_idx]);
|
|
|
|
err = -EEXIST;
|
|
hlist_for_each_entry(node, n, bucket, list) {
|
|
mpath = node->mpath;
|
|
if (mpath->sdata == sdata &&
|
|
ether_addr_equal(dst, mpath->dst))
|
|
goto err_exists;
|
|
}
|
|
|
|
hlist_add_head_rcu(&new_node->list, bucket);
|
|
if (atomic_inc_return(&tbl->entries) >=
|
|
tbl->mean_chain_len * (tbl->hash_mask + 1))
|
|
grow = 1;
|
|
|
|
spin_unlock(&tbl->hashwlock[hash_idx]);
|
|
read_unlock_bh(&pathtbl_resize_lock);
|
|
if (grow) {
|
|
set_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags);
|
|
ieee80211_queue_work(&local->hw, &sdata->work);
|
|
}
|
|
return 0;
|
|
|
|
err_exists:
|
|
spin_unlock(&tbl->hashwlock[hash_idx]);
|
|
read_unlock_bh(&pathtbl_resize_lock);
|
|
kfree(new_node);
|
|
err_node_alloc:
|
|
kfree(new_mpath);
|
|
err_path_alloc:
|
|
return err;
|
|
}
|
|
|
|
|
|
/**
|
|
* mesh_plink_broken - deactivates paths and sends perr when a link breaks
|
|
*
|
|
* @sta: broken peer link
|
|
*
|
|
* This function must be called from the rate control algorithm if enough
|
|
* delivery errors suggest that a peer link is no longer usable.
|
|
*/
|
|
void mesh_plink_broken(struct sta_info *sta)
|
|
{
|
|
struct mesh_table *tbl;
|
|
static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_node *p;
|
|
struct ieee80211_sub_if_data *sdata = sta->sdata;
|
|
int i;
|
|
__le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_DEST_UNREACHABLE);
|
|
|
|
rcu_read_lock();
|
|
tbl = rcu_dereference(mesh_paths);
|
|
for_each_mesh_entry(tbl, p, node, i) {
|
|
mpath = node->mpath;
|
|
if (rcu_dereference(mpath->next_hop) == sta &&
|
|
mpath->flags & MESH_PATH_ACTIVE &&
|
|
!(mpath->flags & MESH_PATH_FIXED)) {
|
|
spin_lock_bh(&mpath->state_lock);
|
|
mpath->flags &= ~MESH_PATH_ACTIVE;
|
|
++mpath->sn;
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
mesh_path_error_tx(sdata->u.mesh.mshcfg.element_ttl,
|
|
mpath->dst, cpu_to_le32(mpath->sn),
|
|
reason, bcast, sdata);
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
/* needs to be called with the corresponding hashwlock taken */
|
|
static void __mesh_path_del(struct mesh_table *tbl, struct mpath_node *node)
|
|
{
|
|
struct mesh_path *mpath;
|
|
mpath = node->mpath;
|
|
spin_lock(&mpath->state_lock);
|
|
mpath->flags |= MESH_PATH_RESOLVING;
|
|
if (mpath->is_gate)
|
|
mesh_gate_del(tbl, mpath);
|
|
hlist_del_rcu(&node->list);
|
|
call_rcu(&node->rcu, mesh_path_node_reclaim);
|
|
spin_unlock(&mpath->state_lock);
|
|
atomic_dec(&tbl->entries);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
|
|
*
|
|
* @sta: mesh peer to match
|
|
*
|
|
* RCU notes: this function is called when a mesh plink transitions from
|
|
* PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
|
|
* allows path creation. This will happen before the sta can be freed (because
|
|
* sta_info_destroy() calls this) so any reader in a rcu read block will be
|
|
* protected against the plink disappearing.
|
|
*/
|
|
void mesh_path_flush_by_nexthop(struct sta_info *sta)
|
|
{
|
|
struct mesh_table *tbl;
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_node *p;
|
|
int i;
|
|
|
|
rcu_read_lock();
|
|
read_lock_bh(&pathtbl_resize_lock);
|
|
tbl = resize_dereference_mesh_paths();
|
|
for_each_mesh_entry(tbl, p, node, i) {
|
|
mpath = node->mpath;
|
|
if (rcu_dereference(mpath->next_hop) == sta) {
|
|
spin_lock(&tbl->hashwlock[i]);
|
|
__mesh_path_del(tbl, node);
|
|
spin_unlock(&tbl->hashwlock[i]);
|
|
}
|
|
}
|
|
read_unlock_bh(&pathtbl_resize_lock);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static void table_flush_by_iface(struct mesh_table *tbl,
|
|
struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_node *p;
|
|
int i;
|
|
|
|
WARN_ON(!rcu_read_lock_held());
|
|
for_each_mesh_entry(tbl, p, node, i) {
|
|
mpath = node->mpath;
|
|
if (mpath->sdata != sdata)
|
|
continue;
|
|
spin_lock_bh(&tbl->hashwlock[i]);
|
|
__mesh_path_del(tbl, node);
|
|
spin_unlock_bh(&tbl->hashwlock[i]);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
|
|
*
|
|
* This function deletes both mesh paths as well as mesh portal paths.
|
|
*
|
|
* @sdata: interface data to match
|
|
*
|
|
*/
|
|
void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct mesh_table *tbl;
|
|
|
|
rcu_read_lock();
|
|
read_lock_bh(&pathtbl_resize_lock);
|
|
tbl = resize_dereference_mesh_paths();
|
|
table_flush_by_iface(tbl, sdata);
|
|
tbl = resize_dereference_mpp_paths();
|
|
table_flush_by_iface(tbl, sdata);
|
|
read_unlock_bh(&pathtbl_resize_lock);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* 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_table *tbl;
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_head *bucket;
|
|
struct hlist_node *n;
|
|
int hash_idx;
|
|
int err = 0;
|
|
|
|
read_lock_bh(&pathtbl_resize_lock);
|
|
tbl = resize_dereference_mesh_paths();
|
|
hash_idx = mesh_table_hash(addr, sdata, tbl);
|
|
bucket = &tbl->hash_buckets[hash_idx];
|
|
|
|
spin_lock(&tbl->hashwlock[hash_idx]);
|
|
hlist_for_each_entry(node, n, bucket, list) {
|
|
mpath = node->mpath;
|
|
if (mpath->sdata == sdata &&
|
|
ether_addr_equal(addr, mpath->dst)) {
|
|
__mesh_path_del(tbl, node);
|
|
goto enddel;
|
|
}
|
|
}
|
|
|
|
err = -ENXIO;
|
|
enddel:
|
|
mesh_paths_generation++;
|
|
spin_unlock(&tbl->hashwlock[hash_idx]);
|
|
read_unlock_bh(&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_send_to_gates - sends pending frames to all known mesh gates
|
|
*
|
|
* @mpath: mesh path whose queue will be emptied
|
|
*
|
|
* If there is only one gate, the frames are transferred from the failed mpath
|
|
* queue to that gate's queue. If there are more than one gates, the frames
|
|
* are copied from each gate to the next. After frames are copied, the
|
|
* mpath queues are emptied onto the transmission queue.
|
|
*/
|
|
int mesh_path_send_to_gates(struct mesh_path *mpath)
|
|
{
|
|
struct ieee80211_sub_if_data *sdata = mpath->sdata;
|
|
struct hlist_node *n;
|
|
struct mesh_table *tbl;
|
|
struct mesh_path *from_mpath = mpath;
|
|
struct mpath_node *gate = NULL;
|
|
bool copy = false;
|
|
struct hlist_head *known_gates;
|
|
|
|
rcu_read_lock();
|
|
tbl = rcu_dereference(mesh_paths);
|
|
known_gates = tbl->known_gates;
|
|
rcu_read_unlock();
|
|
|
|
if (!known_gates)
|
|
return -EHOSTUNREACH;
|
|
|
|
hlist_for_each_entry_rcu(gate, n, known_gates, list) {
|
|
if (gate->mpath->sdata != sdata)
|
|
continue;
|
|
|
|
if (gate->mpath->flags & MESH_PATH_ACTIVE) {
|
|
mpath_dbg(sdata, "Forwarding to %pM\n", gate->mpath->dst);
|
|
mesh_path_move_to_queue(gate->mpath, from_mpath, copy);
|
|
from_mpath = gate->mpath;
|
|
copy = true;
|
|
} else {
|
|
mpath_dbg(sdata,
|
|
"Not forwarding %p (flags %#x)\n",
|
|
gate->mpath, gate->mpath->flags);
|
|
}
|
|
}
|
|
|
|
hlist_for_each_entry_rcu(gate, n, known_gates, list)
|
|
if (gate->mpath->sdata == sdata) {
|
|
mpath_dbg(sdata, "Sending to %pM\n", gate->mpath->dst);
|
|
mesh_path_tx_pending(gate->mpath);
|
|
}
|
|
|
|
return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
*
|
|
* 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)
|
|
{
|
|
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 within 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)) != NULL)
|
|
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) {
|
|
del_timer_sync(&mpath->timer);
|
|
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)
|
|
{
|
|
struct mesh_table *tbl_path, *tbl_mpp;
|
|
int ret;
|
|
|
|
tbl_path = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
|
|
if (!tbl_path)
|
|
return -ENOMEM;
|
|
tbl_path->free_node = &mesh_path_node_free;
|
|
tbl_path->copy_node = &mesh_path_node_copy;
|
|
tbl_path->mean_chain_len = MEAN_CHAIN_LEN;
|
|
tbl_path->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
|
|
if (!tbl_path->known_gates) {
|
|
ret = -ENOMEM;
|
|
goto free_path;
|
|
}
|
|
INIT_HLIST_HEAD(tbl_path->known_gates);
|
|
|
|
|
|
tbl_mpp = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
|
|
if (!tbl_mpp) {
|
|
ret = -ENOMEM;
|
|
goto free_path;
|
|
}
|
|
tbl_mpp->free_node = &mesh_path_node_free;
|
|
tbl_mpp->copy_node = &mesh_path_node_copy;
|
|
tbl_mpp->mean_chain_len = MEAN_CHAIN_LEN;
|
|
tbl_mpp->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
|
|
if (!tbl_mpp->known_gates) {
|
|
ret = -ENOMEM;
|
|
goto free_mpp;
|
|
}
|
|
INIT_HLIST_HEAD(tbl_mpp->known_gates);
|
|
|
|
/* Need no locking since this is during init */
|
|
RCU_INIT_POINTER(mesh_paths, tbl_path);
|
|
RCU_INIT_POINTER(mpp_paths, tbl_mpp);
|
|
|
|
return 0;
|
|
|
|
free_mpp:
|
|
mesh_table_free(tbl_mpp, true);
|
|
free_path:
|
|
mesh_table_free(tbl_path, true);
|
|
return ret;
|
|
}
|
|
|
|
void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct mesh_table *tbl;
|
|
struct mesh_path *mpath;
|
|
struct mpath_node *node;
|
|
struct hlist_node *p;
|
|
int i;
|
|
|
|
rcu_read_lock();
|
|
tbl = rcu_dereference(mesh_paths);
|
|
for_each_mesh_entry(tbl, p, node, i) {
|
|
if (node->mpath->sdata != sdata)
|
|
continue;
|
|
mpath = node->mpath;
|
|
if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
|
|
(!(mpath->flags & MESH_PATH_FIXED)) &&
|
|
time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
|
|
mesh_path_del(mpath->dst, mpath->sdata);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
void mesh_pathtbl_unregister(void)
|
|
{
|
|
/* no need for locking during exit path */
|
|
mesh_table_free(rcu_dereference_protected(mesh_paths, 1), true);
|
|
mesh_table_free(rcu_dereference_protected(mpp_paths, 1), true);
|
|
}
|