ubuntu-linux-kernel/net/mac80211/ocb.c

249 lines
6.8 KiB
C

/*
* OCB mode implementation
*
* Copyright: (c) 2014 Czech Technical University in Prague
* (c) 2014 Volkswagen Group Research
* Author: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
* Funded by: Volkswagen Group Research
*
* 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/delay.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <net/mac80211.h>
#include <asm/unaligned.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#define IEEE80211_OCB_HOUSEKEEPING_INTERVAL (60 * HZ)
#define IEEE80211_OCB_PEER_INACTIVITY_LIMIT (240 * HZ)
#define IEEE80211_OCB_MAX_STA_ENTRIES 128
/**
* enum ocb_deferred_task_flags - mac80211 OCB deferred tasks
* @OCB_WORK_HOUSEKEEPING: run the periodic OCB housekeeping tasks
*
* These flags are used in @wrkq_flags field of &struct ieee80211_if_ocb
*/
enum ocb_deferred_task_flags {
OCB_WORK_HOUSEKEEPING,
};
void ieee80211_ocb_rx_no_sta(struct ieee80211_sub_if_data *sdata,
const u8 *bssid, const u8 *addr,
u32 supp_rates)
{
struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
struct ieee80211_local *local = sdata->local;
struct ieee80211_chanctx_conf *chanctx_conf;
struct ieee80211_supported_band *sband;
enum nl80211_bss_scan_width scan_width;
struct sta_info *sta;
int band;
/* XXX: Consider removing the least recently used entry and
* allow new one to be added.
*/
if (local->num_sta >= IEEE80211_OCB_MAX_STA_ENTRIES) {
net_info_ratelimited("%s: No room for a new OCB STA entry %pM\n",
sdata->name, addr);
return;
}
ocb_dbg(sdata, "Adding new OCB station %pM\n", addr);
rcu_read_lock();
chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
if (WARN_ON_ONCE(!chanctx_conf)) {
rcu_read_unlock();
return;
}
band = chanctx_conf->def.chan->band;
scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
rcu_read_unlock();
sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
if (!sta)
return;
/* Add only mandatory rates for now */
sband = local->hw.wiphy->bands[band];
sta->sta.supp_rates[band] =
ieee80211_mandatory_rates(sband, scan_width);
spin_lock(&ifocb->incomplete_lock);
list_add(&sta->list, &ifocb->incomplete_stations);
spin_unlock(&ifocb->incomplete_lock);
ieee80211_queue_work(&local->hw, &sdata->work);
}
static struct sta_info *ieee80211_ocb_finish_sta(struct sta_info *sta)
__acquires(RCU)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
u8 addr[ETH_ALEN];
memcpy(addr, sta->sta.addr, ETH_ALEN);
ocb_dbg(sdata, "Adding new IBSS station %pM (dev=%s)\n",
addr, sdata->name);
sta_info_move_state(sta, IEEE80211_STA_AUTH);
sta_info_move_state(sta, IEEE80211_STA_ASSOC);
sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
rate_control_rate_init(sta);
/* If it fails, maybe we raced another insertion? */
if (sta_info_insert_rcu(sta))
return sta_info_get(sdata, addr);
return sta;
}
static void ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
ocb_dbg(sdata, "Running ocb housekeeping\n");
ieee80211_sta_expire(sdata, IEEE80211_OCB_PEER_INACTIVITY_LIMIT);
mod_timer(&ifocb->housekeeping_timer,
round_jiffies(jiffies + IEEE80211_OCB_HOUSEKEEPING_INTERVAL));
}
void ieee80211_ocb_work(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
struct sta_info *sta;
if (ifocb->joined != true)
return;
sdata_lock(sdata);
spin_lock_bh(&ifocb->incomplete_lock);
while (!list_empty(&ifocb->incomplete_stations)) {
sta = list_first_entry(&ifocb->incomplete_stations,
struct sta_info, list);
list_del(&sta->list);
spin_unlock_bh(&ifocb->incomplete_lock);
ieee80211_ocb_finish_sta(sta);
rcu_read_unlock();
spin_lock_bh(&ifocb->incomplete_lock);
}
spin_unlock_bh(&ifocb->incomplete_lock);
if (test_and_clear_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags))
ieee80211_ocb_housekeeping(sdata);
sdata_unlock(sdata);
}
static void ieee80211_ocb_housekeeping_timer(struct timer_list *t)
{
struct ieee80211_sub_if_data *sdata =
from_timer(sdata, t, u.ocb.housekeeping_timer);
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
ieee80211_queue_work(&local->hw, &sdata->work);
}
void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
timer_setup(&ifocb->housekeeping_timer,
ieee80211_ocb_housekeeping_timer, 0);
INIT_LIST_HEAD(&ifocb->incomplete_stations);
spin_lock_init(&ifocb->incomplete_lock);
}
int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata,
struct ocb_setup *setup)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
u32 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID;
int err;
if (ifocb->joined == true)
return -EINVAL;
sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
sdata->smps_mode = IEEE80211_SMPS_OFF;
sdata->needed_rx_chains = sdata->local->rx_chains;
mutex_lock(&sdata->local->mtx);
err = ieee80211_vif_use_channel(sdata, &setup->chandef,
IEEE80211_CHANCTX_SHARED);
mutex_unlock(&sdata->local->mtx);
if (err)
return err;
ieee80211_bss_info_change_notify(sdata, changed);
ifocb->joined = true;
set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
ieee80211_queue_work(&local->hw, &sdata->work);
netif_carrier_on(sdata->dev);
return 0;
}
int ieee80211_ocb_leave(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
ifocb->joined = false;
sta_info_flush(sdata);
spin_lock_bh(&ifocb->incomplete_lock);
while (!list_empty(&ifocb->incomplete_stations)) {
sta = list_first_entry(&ifocb->incomplete_stations,
struct sta_info, list);
list_del(&sta->list);
spin_unlock_bh(&ifocb->incomplete_lock);
sta_info_free(local, sta);
spin_lock_bh(&ifocb->incomplete_lock);
}
spin_unlock_bh(&ifocb->incomplete_lock);
netif_carrier_off(sdata->dev);
clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB);
mutex_lock(&sdata->local->mtx);
ieee80211_vif_release_channel(sdata);
mutex_unlock(&sdata->local->mtx);
skb_queue_purge(&sdata->skb_queue);
del_timer_sync(&sdata->u.ocb.housekeeping_timer);
/* If the timer fired while we waited for it, it will have
* requeued the work. Now the work will be running again
* but will not rearm the timer again because it checks
* whether we are connected to the network or not -- at this
* point we shouldn't be anymore.
*/
return 0;
}