/*
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/timer.h>
#include <linux/rtnetlink.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#include "sta_info.h"
#include "debugfs_sta.h"
#include "mesh.h"
#include "wme.h"
/**
* DOC: STA information lifetime rules
*
* STA info structures (&struct sta_info) are managed in a hash table
* for faster lookup and a list for iteration. They are managed using
* RCU, i.e. access to the list and hash table is protected by RCU.
*
* Upon allocating a STA info structure with sta_info_alloc(), the caller
* owns that structure. It must then insert it into the hash table using
* either sta_info_insert() or sta_info_insert_rcu(); only in the latter
* case (which acquires an rcu read section but must not be called from
* within one) will the pointer still be valid after the call. Note that
* the caller may not do much with the STA info before inserting it, in
* particular, it may not start any mesh peer link management or add
* encryption keys.
*
* When the insertion fails (sta_info_insert()) returns non-zero), the
* structure will have been freed by sta_info_insert()!
*
* Station entries are added by mac80211 when you establish a link with a
* peer. This means different things for the different type of interfaces
* we support. For a regular station this mean we add the AP sta when we
* receive an association response from the AP. For IBSS this occurs when
* get to know about a peer on the same IBSS. For WDS we add the sta for
* the peer immediately upon device open. When using AP mode we add stations
* for each respective station upon request from userspace through nl80211.
*
* In order to remove a STA info structure, various sta_info_destroy_*()
* calls are available.
*
* There is no concept of ownership on a STA entry, each structure is
* owned by the global hash table/list until it is removed. All users of
* the structure need to be RCU protected so that the structure won't be
* freed before they are done using it.
*/
/* Caller must hold local->sta_mtx */
static int sta_info_hash_del(struct ieee80211_local *local,
struct sta_info *sta)
{
struct sta_info *s;
s = rcu_dereference_protected(local->sta_hash[STA_HASH(sta->sta.addr)],
lockdep_is_held(&local->sta_mtx));
if <