linux/net/mac80211/sta_info.c

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/*
* 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"
/**
* 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 assocation 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 imediately 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_lock */
static int sta_info_hash_del(struct ieee80211_local *local,
struct sta_info *sta)
{
struct sta_info *s;
s = local->sta_hash[STA_HASH(sta->sta.addr)];
if (!s)
return -ENOENT;
if (s == sta) {
rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)],
s->hnext);
return 0;
}
while (s->hnext && s->hnext != sta)
s = s->hnext;
if (s->hnext) {
rcu_assign_pointer(s->hnext, sta->hnext);
return 0;
}
return -ENOENT;
}
/* protected by RCU */
struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
const u8 *addr)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
while (sta) {
if (sta->sdata == sdata &&
memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
break;
sta = rcu_dereference_check(sta->hnext,
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
}
return sta;
}
/*
* Get sta info either from the specified interface
* or from one of its vlans
*/
struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
const u8 *addr)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
while (sta) {
if ((sta->sdata == sdata ||
(sta->sdata->bss && sta->sdata->bss == sdata->bss)) &&
memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
break;
sta = rcu_dereference_check(sta->hnext,
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
}
return sta;
}
struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
int idx)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
int i = 0;
list_for_each_entry_rcu(sta, &local->sta_list, list) {
if (sdata != sta->sdata)
continue;
if (i < idx) {
++i;
continue;
}
return sta;
}
return NULL;
}
/**
* __sta_info_free - internal STA free helper
*
* @local: pointer to the global information
* @sta: STA info to free
*
* This function must undo everything done by sta_info_alloc()
* that may happen before sta_info_insert().
*/
static void __sta_info_free(struct ieee80211_local *local,
struct sta_info *sta)
{
if (sta->rate_ctrl) {
rate_control_free_sta(sta);
rate_control_put(sta->rate_ctrl);
}
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
wiphy_debug(local->hw.wiphy, "Destroyed STA %pM\n", sta->sta.addr);
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
kfree(sta);
}
/* Caller must hold local->sta_lock */
static void sta_info_hash_add(struct ieee80211_local *local,
struct sta_info *sta)
{
sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)];
rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta);
}
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
static void sta_unblock(struct work_struct *wk)
{
struct sta_info *sta;
sta = container_of(wk, struct sta_info, drv_unblock_wk);
if (sta->dead)
return;
if (!test_sta_flags(sta, WLAN_STA_PS_STA))
ieee80211_sta_ps_deliver_wakeup(sta);
else if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL)) {
clear_sta_flags(sta, WLAN_STA_PS_DRIVER);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
ieee80211_sta_ps_deliver_poll_response(sta);
} else
clear_sta_flags(sta, WLAN_STA_PS_DRIVER);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
}
static int sta_prepare_rate_control(struct ieee80211_local *local,
struct sta_info *sta, gfp_t gfp)
{
if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
return 0;
sta->rate_ctrl = rate_control_get(local->rate_ctrl);
sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
&sta->sta, gfp);
if (!sta->rate_ctrl_priv) {
rate_control_put(sta->rate_ctrl);
return -ENOMEM;
}
return 0;
}
struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
u8 *addr, gfp_t gfp)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
int i;
sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp);
if (!sta)
return NULL;
spin_lock_init(&sta->lock);
spin_lock_init(&sta->flaglock);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
INIT_WORK(&sta->drv_unblock_wk, sta_unblock);
INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work);
mutex_init(&sta->ampdu_mlme.mtx);
memcpy(sta->sta.addr, addr, ETH_ALEN);
sta->local = local;
sta->sdata = sdata;
sta->last_rx = jiffies;
ewma_init(&sta->avg_signal, 1024, 8);
if (sta_prepare_rate_control(local, sta, gfp)) {
kfree(sta);
return NULL;
}
for (i = 0; i < STA_TID_NUM; i++) {
/*
* timer_to_tid must be initialized with identity mapping
* to enable session_timer's data differentiation. See
* sta_rx_agg_session_timer_expired for usage.
*/
sta->timer_to_tid[i] = i;
}
skb_queue_head_init(&sta->ps_tx_buf);
skb_queue_head_init(&sta->tx_filtered);
for (i = 0; i < NUM_RX_DATA_QUEUES; i++)
sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX);
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr);
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
#ifdef CONFIG_MAC80211_MESH
sta->plink_state = PLINK_LISTEN;
init_timer(&sta->plink_timer);
#endif
return sta;
}
static int sta_info_finish_insert(struct sta_info *sta, bool async)
{
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct station_info sinfo;
unsigned long flags;
int err = 0;
lockdep_assert_held(&local->sta_mtx);
/* notify driver */
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
sdata = container_of(sdata->bss,
struct ieee80211_sub_if_data,
u.ap);
err = drv_sta_add(local, sdata, &sta->sta);
if (err) {
if (!async)
return err;
printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to driver (%d)"
" - keeping it anyway.\n",
sdata->name, sta->sta.addr, err);
} else {
sta->uploaded = true;
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
if (async)
wiphy_debug(local->hw.wiphy,
"Finished adding IBSS STA %pM\n",
sta->sta.addr);
#endif
}
sdata = sta->sdata;
if (!async) {
local->num_sta++;
local->sta_generation++;
smp_mb();
/* make the station visible */
spin_lock_irqsave(&local->sta_lock, flags);
sta_info_hash_add(local, sta);
spin_unlock_irqrestore(&local->sta_lock, flags);
}
list_add(&sta->list, &local->sta_list);
ieee80211_sta_debugfs_add(sta);
rate_control_add_sta_debugfs(sta);
sinfo.filled = 0;
sinfo.generation = local->sta_generation;
cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL);
return 0;
}
static void sta_info_finish_pending(struct ieee80211_local *local)
{
struct sta_info *sta;
unsigned long flags;
spin_lock_irqsave(&local->sta_lock, flags);
while (!list_empty(&local->sta_pending_list)) {
sta = list_first_entry(&local->sta_pending_list,
struct sta_info, list);
list_del(&sta->list);
spin_unlock_irqrestore(&local->sta_lock, flags);
sta_info_finish_insert(sta, true);
spin_lock_irqsave(&local->sta_lock, flags);
}
spin_unlock_irqrestore(&local->sta_lock, flags);
}
static void sta_info_finish_work(struct work_struct *work)
{
struct ieee80211_local *local =
container_of(work, struct ieee80211_local, sta_finish_work);
mutex_lock(&local->sta_mtx);
sta_info_finish_pending(local);
mutex_unlock(&local->sta_mtx);
}
int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU)
{
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
unsigned long flags;
int err = 0;
/*
* Can't be a WARN_ON because it can be triggered through a race:
* something inserts a STA (on one CPU) without holding the RTNL
* and another CPU turns off the net device.
*/
if (unlikely(!ieee80211_sdata_running(sdata))) {
err = -ENETDOWN;
rcu_read_lock();
goto out_free;
}
if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 ||
is_multicast_ether_addr(sta->sta.addr))) {
err = -EINVAL;
rcu_read_lock();
goto out_free;
}
/*
* In ad-hoc mode, we sometimes need to insert stations
* from tasklet context from the RX path. To avoid races,
* always do so in that case -- see the comment below.
*/
if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
spin_lock_irqsave(&local->sta_lock, flags);
/* check if STA exists already */
if (sta_info_get_bss(sdata, sta->sta.addr)) {
spin_unlock_irqrestore(&local->sta_lock, flags);
rcu_read_lock();
err = -EEXIST;
goto out_free;
}
local->num_sta++;
local->sta_generation++;
smp_mb();
sta_info_hash_add(local, sta);
list_add_tail(&sta->list, &local->sta_pending_list);
rcu_read_lock();
spin_unlock_irqrestore(&local->sta_lock, flags);
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
wiphy_debug(local->hw.wiphy, "Added IBSS STA %pM\n",
sta->sta.addr);
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
ieee80211_queue_work(&local->hw, &local->sta_finish_work);
return 0;
}
/*
* On first glance, this will look racy, because the code
* below this point, which inserts a station with sleeping,
* unlocks the sta_lock between checking existence in the
* hash table and inserting into it.
*
* However, it is not racy against itself because it keeps
* the mutex locked. It still seems to race against the
* above code that atomically inserts the station... That,
* however, is not true because the above code can only
* be invoked for IBSS interfaces, and the below code will
* not be -- and the two do not race against each other as
* the hash table also keys off the interface.
*/
might_sleep();
mutex_lock(&local->sta_mtx);
spin_lock_irqsave(&local->sta_lock, flags);
/* check if STA exists already */
if (sta_info_get_bss(sdata, sta->sta.addr)) {
spin_unlock_irqrestore(&local->sta_lock, flags);
mutex_unlock(&local->sta_mtx);
rcu_read_lock();
err = -EEXIST;
goto out_free;
}
spin_unlock_irqrestore(&local->sta_lock, flags);
err = sta_info_finish_insert(sta, false);
if (err) {
mutex_unlock(&local->sta_mtx);
rcu_read_lock();
goto out_free;
}
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
wiphy_debug(local->hw.wiphy, "Inserted STA %pM\n", sta->sta.addr);
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
/* move reference to rcu-protected */
rcu_read_lock();
mutex_unlock(&local->sta_mtx);
if (ieee80211_vif_is_mesh(&sdata->vif))
mesh_accept_plinks_update(sdata);
return 0;
out_free:
BUG_ON(!err);
__sta_info_free(local, sta);
return err;
}
int sta_info_insert(struct sta_info *sta)
{
int err = sta_info_insert_rcu(sta);
rcu_read_unlock();
return err;
}
static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid)
{
/*
* This format has been mandated by the IEEE specifications,
* so this line may not be changed to use the __set_bit() format.
*/
bss->tim[aid / 8] |= (1 << (aid % 8));
}
static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid)
{
/*
* This format has been mandated by the IEEE specifications,
* so this line may not be changed to use the __clear_bit() format.
*/
bss->tim[aid / 8] &= ~(1 << (aid % 8));
}
static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss,
struct sta_info *sta)
{
BUG_ON(!bss);
__bss_tim_set(bss, sta->sta.aid);
if (sta->local->ops->set_tim) {
sta->local->tim_in_locked_section = true;
drv_set_tim(sta->local, &sta->sta, true);
sta->local->tim_in_locked_section = false;
}
}
void sta_info_set_tim_bit(struct sta_info *sta)
{
unsigned long flags;
BUG_ON(!sta->sdata->bss);
spin_lock_irqsave(&sta->local->sta_lock, flags);
__sta_info_set_tim_bit(sta->sdata->bss, sta);
spin_unlock_irqrestore(&sta->local->sta_lock, flags);
}
static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss,
struct sta_info *sta)
{
BUG_ON(!bss);
__bss_tim_clear(bss, sta->sta.aid);
if (sta->local->ops->set_tim) {
sta->local->tim_in_locked_section = true;
drv_set_tim(sta->local, &sta->sta, false);
sta->local->tim_in_locked_section = false;
}
}
void sta_info_clear_tim_bit(struct sta_info *sta)
{
unsigned long flags;
BUG_ON(!sta->sdata->bss);
spin_lock_irqsave(&sta->local->sta_lock, flags);
__sta_info_clear_tim_bit(sta->sdata->bss, sta);
spin_unlock_irqrestore(&sta->local->sta_lock, flags);
}
static int sta_info_buffer_expired(struct sta_info *sta,
struct sk_buff *skb)
{
struct ieee80211_tx_info *info;
int timeout;
if (!skb)
return 0;
info = IEEE80211_SKB_CB(skb);
/* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
timeout = (sta->listen_interval *
sta->sdata->vif.bss_conf.beacon_int *
32 / 15625) * HZ;
if (timeout < STA_TX_BUFFER_EXPIRE)
timeout = STA_TX_BUFFER_EXPIRE;
return time_after(jiffies, info->control.jiffies + timeout);
}
static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
struct sta_info *sta)
{
unsigned long flags;
struct sk_buff *skb;
struct ieee80211_sub_if_data *sdata;
if (skb_queue_empty(&sta->ps_tx_buf))
return false;
for (;;) {
spin_lock_irqsave(&sta->ps_tx_buf.lock, flags);
skb = skb_peek(&sta->ps_tx_buf);
if (sta_info_buffer_expired(sta, skb))
skb = __skb_dequeue(&sta->ps_tx_buf);
else
skb = NULL;
spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags);
if (!skb)
break;
sdata = sta->sdata;
local->total_ps_buffered--;
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n",
sta->sta.addr);
#endif
dev_kfree_skb(skb);
if (skb_queue_empty(&sta->ps_tx_buf))
sta_info_clear_tim_bit(sta);
}
return true;
}
static int __must_check __sta_info_destroy(struct sta_info *sta)
{
struct ieee80211_local *local;
struct ieee80211_sub_if_data *sdata;
struct sk_buff *skb;
unsigned long flags;
int ret, i;
might_sleep();
if (!sta)
return -ENOENT;
local = sta->local;
sdata = sta->sdata;
/*
* Before removing the station from the driver and
* rate control, it might still start new aggregation
* sessions -- block that to make sure the tear-down
* will be sufficient.
*/
set_sta_flags(sta, WLAN_STA_BLOCK_BA);
ieee80211_sta_tear_down_BA_sessions(sta, true);
spin_lock_irqsave(&local->sta_lock, flags);
ret = sta_info_hash_del(local, sta);
/* this might still be the pending list ... which is fine */
if (!ret)
list_del(&sta->list);
spin_unlock_irqrestore(&local->sta_lock, flags);
if (ret)
return ret;
for (i = 0; i < NUM_DEFAULT_KEYS; i++)
ieee80211_key_free(local, sta->gtk[i]);
if (sta->ptk)
ieee80211_key_free(local, sta->ptk);
sta->dead = true;
if (test_and_clear_sta_flags(sta,
WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) {
BUG_ON(!sdata->bss);
atomic_dec(&sdata->bss->num_sta_ps);
__sta_info_clear_tim_bit(sdata->bss, sta);
}
local->num_sta--;
local->sta_generation++;
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
rcu_assign_pointer(sdata->u.vlan.sta, NULL);
if (sta->uploaded) {
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
sdata = container_of(sdata->bss,
struct ieee80211_sub_if_data,
u.ap);
drv_sta_remove(local, sdata, &sta->sta);
sdata = sta->sdata;
}
/*
* At this point, after we wait for an RCU grace period,
* neither mac80211 nor the driver can reference this
* sta struct any more except by still existing timers
* associated with this station that we clean up below.
*/
synchronize_rcu();
#ifdef CONFIG_MAC80211_MESH
if (ieee80211_vif_is_mesh(&sdata->vif))
mesh_accept_plinks_update(sdata);
#endif
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr);
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
cancel_work_sync(&sta->drv_unblock_wk);
rate_control_remove_sta_debugfs(sta);
ieee80211_sta_debugfs_remove(sta);
#ifdef CONFIG_MAC80211_MESH
if (ieee80211_vif_is_mesh(&sta->sdata->vif)) {
mesh_plink_deactivate(sta);
del_timer_sync(&sta->plink_timer);
}
#endif
while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
local->total_ps_buffered--;
dev_kfree_skb_any(skb);
}
while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL)
dev_kfree_skb_any(skb);
__sta_info_free(local, sta);
return 0;
}
int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr)
{
struct sta_info *sta;
int ret;
mutex_lock(&sdata->local->sta_mtx);
sta = sta_info_get(sdata, addr);
ret = __sta_info_destroy(sta);
mutex_unlock(&sdata->local->sta_mtx);
return ret;
}
int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
const u8 *addr)
{
struct sta_info *sta;
int ret;
mutex_lock(&sdata->local->sta_mtx);
sta = sta_info_get_bss(sdata, addr);
ret = __sta_info_destroy(sta);
mutex_unlock(&sdata->local->sta_mtx);
return ret;
}
static void sta_info_cleanup(unsigned long data)
{
struct ieee80211_local *local = (struct ieee80211_local *) data;
struct sta_info *sta;
bool timer_needed = false;
rcu_read_lock();
list_for_each_entry_rcu(sta, &local->sta_list, list)
if (sta_info_cleanup_expire_buffered(local, sta))
timer_needed = true;
rcu_read_unlock();
if (local->quiescing)
return;
if (!timer_needed)
return;
local->sta_cleanup.expires =
round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
add_timer(&local->sta_cleanup);
}
void sta_info_init(struct ieee80211_local *local)
{
spin_lock_init(&local->sta_lock);
mutex_init(&local->sta_mtx);
INIT_LIST_HEAD(&local->sta_list);
INIT_LIST_HEAD(&local->sta_pending_list);
INIT_WORK(&local->sta_finish_work, sta_info_finish_work);
setup_timer(&local->sta_cleanup, sta_info_cleanup,
(unsigned long)local);
local->sta_cleanup.expires =
round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
}
int sta_info_start(struct ieee80211_local *local)
{
add_timer(&local->sta_cleanup);
return 0;
}
void sta_info_stop(struct ieee80211_local *local)
{
del_timer(&local->sta_cleanup);
sta_info_flush(local, NULL);
}
/**
* sta_info_flush - flush matching STA entries from the STA table
*
* Returns the number of removed STA entries.
*
* @local: local interface data
* @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs
*/
int sta_info_flush(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata)
{
struct sta_info *sta, *tmp;
int ret = 0;
might_sleep();
mutex_lock(&local->sta_mtx);
sta_info_finish_pending(local);
list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
if (!sdata || sdata == sta->sdata)
WARN_ON(__sta_info_destroy(sta));
}
mutex_unlock(&local->sta_mtx);
return ret;
}
void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
unsigned long exp_time)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta, *tmp;
mutex_lock(&local->sta_mtx);
list_for_each_entry_safe(sta, tmp, &local->sta_list, list)
if (time_after(jiffies, sta->last_rx + exp_time)) {
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG "%s: expiring inactive STA %pM\n",
sdata->name, sta->sta.addr);
#endif
WARN_ON(__sta_info_destroy(sta));
}
mutex_unlock(&local->sta_mtx);
}
struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw,
const u8 *addr,
const u8 *localaddr)
{
struct sta_info *sta, *nxt;
/*
* Just return a random station if localaddr is NULL
* ... first in list.
*/
for_each_sta_info(hw_to_local(hw), addr, sta, nxt) {
if (localaddr &&
compare_ether_addr(sta->sdata->vif.addr, localaddr) != 0)
continue;
if (!sta->uploaded)
return NULL;
return &sta->sta;
}
return NULL;
}
EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr);
struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif,
const u8 *addr)
{
struct sta_info *sta;
if (!vif)
return NULL;
sta = sta_info_get_bss(vif_to_sdata(vif), addr);
if (!sta)
return NULL;
if (!sta->uploaded)
return NULL;
return &sta->sta;
}
EXPORT_SYMBOL(ieee80211_find_sta);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
static void clear_sta_ps_flags(void *_sta)
{
struct sta_info *sta = _sta;
clear_sta_flags(sta, WLAN_STA_PS_DRIVER | WLAN_STA_PS_STA);
}
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
/* powersave support code */
void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
int sent, buffered;
if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
if (!skb_queue_empty(&sta->ps_tx_buf))
sta_info_clear_tim_bit(sta);
/* Send all buffered frames to the station */
sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered);
buffered = ieee80211_add_pending_skbs_fn(local, &sta->ps_tx_buf,
clear_sta_ps_flags, sta);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
sent += buffered;
local->total_ps_buffered -= buffered;
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames "
"since STA not sleeping anymore\n", sdata->name,
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
sta->sta.addr, sta->sta.aid, sent - buffered, buffered);
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
}
void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb;
int no_pending_pkts;
skb = skb_dequeue(&sta->tx_filtered);
if (!skb) {
skb = skb_dequeue(&sta->ps_tx_buf);
if (skb)
local->total_ps_buffered--;
}
no_pending_pkts = skb_queue_empty(&sta->tx_filtered) &&
skb_queue_empty(&sta->ps_tx_buf);
if (skb) {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr =
(struct ieee80211_hdr *) skb->data;
/*
* Tell TX path to send this frame even though the STA may
* still remain is PS mode after this frame exchange.
*/
info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE;
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
sta->sta.addr, sta->sta.aid,
skb_queue_len(&sta->ps_tx_buf));
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
/* Use MoreData flag to indicate whether there are more
* buffered frames for this STA */
if (no_pending_pkts)
hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
else
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
ieee80211_add_pending_skb(local, skb);
if (no_pending_pkts)
sta_info_clear_tim_bit(sta);
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
} else {
/*
* FIXME: This can be the result of a race condition between
* us expiring a frame and the station polling for it.
* Should we send it a null-func frame indicating we
* have nothing buffered for it?
*/
printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
"though there are no buffered frames for it\n",
sdata->name, sta->sta.addr);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
}
}
void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
struct ieee80211_sta *pubsta, bool block)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
trace_api_sta_block_awake(sta->local, pubsta, block);
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
if (block)
set_sta_flags(sta, WLAN_STA_PS_DRIVER);
else if (test_sta_flags(sta, WLAN_STA_PS_DRIVER))
mac80211: async station powersave handling Some devices require that all frames to a station are flushed when that station goes into powersave mode before being able to send frames to that station again when it wakes up or polls -- all in order to avoid reordering and too many or too few frames being sent to the station when it polls. Normally, this is the case unless the station goes to sleep and wakes up very quickly again. But in that case, frames for it may be pending on the hardware queues, and thus races could happen in the case of multiple hardware queues used for QoS/WMM. Normally this isn't a problem, but with the iwlwifi mechanism we need to make sure the race doesn't happen. This makes mac80211 able to cope with the race with driver help by a new WLAN_STA_PS_DRIVER per-station flag that can be controlled by the driver and tells mac80211 whether it can transmit frames or not. This flag must be set according to very specific rules outlined in the documentation for the function that controls it. When we buffer new frames for the station, we normally set the TIM bit right away, but while the driver has blocked transmission to that sta we need to avoid that as well since we cannot respond to the station if it wakes up due to the TIM bit. Once the driver unblocks, we can set the TIM bit. Similarly, when the station just wakes up, we need to wait until all other frames are flushed before we can transmit frames to that station, so the same applies here, we need to wait for the driver to give the OK. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 11:35:50 +01:00
ieee80211_queue_work(hw, &sta->drv_unblock_wk);
}
EXPORT_SYMBOL(ieee80211_sta_block_awake);