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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"
#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_lock */
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_lock));
if (!s)
return -ENOENT;
if (s == sta) {
rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)],
s->hnext);
return 0;
}
while (rcu_access_pointer(s->hnext) &&
rcu_access_pointer(s->hnext) != sta)
s = rcu_dereference_protected(s->hnext,
lockdep_is_held(&local->sta_lock));
if (rcu_access_pointer(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)],
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
while (sta) {
if (sta->sdata == sdata && !sta->dummy &&
memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
break;
sta = rcu_dereference_check(sta->hnext,
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
}
return sta;
}
/* get a station info entry even if it is a dummy station*/
struct sta_info *sta_info_get_rx(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)],
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,
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)],
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)) &&
!sta->dummy &&
memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
break;
sta = rcu_dereference_check(sta->hnext,
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 (including dummy stations)
*/
struct sta_info *sta_info_get_bss_rx(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)],
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,
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);
}
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_flag(sta, WLAN_STA_PS_STA))
ieee80211_sta_ps_deliver_wakeup(sta);
else if (test_and_clear_sta_flag(sta, WLAN_STA_PSPOLL)) {
clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
local_bh_disable();
ieee80211_sta_ps_deliver_poll_response(sta);
local_bh_enable();
} else if (test_and_clear_sta_flag(sta, WLAN_STA_UAPSD)) {
clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
local_bh_disable();
ieee80211_sta_ps_deliver_uapsd(sta);
local_bh_enable();
} else
clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
}
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;
struct timespec uptime;
int i;
sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp);
if (!sta)
return NULL;
spin_lock_init(&sta->lock);
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;
do_posix_clock_monotonic_gettime(&uptime);
sta->last_connected = uptime.tv_sec;
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;
}
for (i = 0; i < IEEE80211_NUM_ACS; i++) {
skb_queue_head_init(&sta->ps_tx_buf[i]);
skb_queue_head_init(&sta->tx_filtered[i]);
}
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 = NL80211_PLINK_LISTEN;
init_timer(&sta->plink_timer);
#endif
return sta;
}
static int sta_info_finish_insert(struct sta_info *sta,
bool async, bool dummy_reinsert)
{
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);
if (!sta->dummy || dummy_reinsert) {
/* 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 (!dummy_reinsert) {
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);
} else {
sta->dummy = false;
}
if (!sta->dummy) {
ieee80211_sta_debugfs_add(sta);
rate_control_add_sta_debugfs(sta);
memset(&sinfo, 0, sizeof(sinfo));
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, false);
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);
}
static int sta_info_insert_check(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
/*
* 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)))
return -ENETDOWN;
if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 ||
is_multicast_ether_addr(sta->sta.addr)))
return -EINVAL;
return 0;
}
static int sta_info_insert_ibss(struct sta_info *sta) __acquires(RCU)
{
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
unsigned long flags;
spin_lock_irqsave(&local->sta_lock, flags);
/* check if STA exists already */
if (sta_info_get_bss_rx(sdata, sta->sta.addr)) {
spin_unlock_irqrestore(&local->sta_lock, flags);
rcu_read_lock();
return -EEXIST;
}
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;
}
/*
* should be called with sta_mtx locked
* this function replaces the mutex lock
* with a RCU lock
*/
static int sta_info_insert_non_ibss(struct sta_info *sta) __acquires(RCU)
{
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
unsigned long flags;
struct sta_info *exist_sta;
bool dummy_reinsert = false;
int err = 0;
lockdep_assert_held(&local->sta_mtx);
/*
* On first glance, this will look racy, because the code
* in this function, 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.
*/
spin_lock_irqsave(&local->sta_lock, flags);
/*
* check if STA exists already.
* only accept a scenario of a second call to sta_info_insert_non_ibss
* with a dummy station entry that was inserted earlier
* in that case - assume that the dummy station flag should
* be removed.
*/
exist_sta = sta_info_get_bss_rx(sdata, sta->sta.addr);
if (exist_sta) {
if (exist_sta == sta && sta->dummy) {
dummy_reinsert = true;
} else {
spin_unlock_irqrestore(&local->sta_lock, flags);
mutex_unlock(&local->sta_mtx);
rcu_read_lock();
return -EEXIST;
}
}
spin_unlock_irqrestore(&local->sta_lock, flags);
err = sta_info_finish_insert(sta, false, dummy_reinsert);
if (err) {
mutex_unlock(&local->sta_mtx);
rcu_read_lock();
return err;
}
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
wiphy_debug(local->hw.wiphy, "Inserted %sSTA %pM\n",
sta->dummy ? "dummy " : "", 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;
}
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;
int err = 0;
err = sta_info_insert_check(sta);
if (err) {
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) {
err = sta_info_insert_ibss(sta);
if (err)
goto out_free;
return 0;
}
/*
* It might seem that the function called below is in race against
* the function call above 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);
err = sta_info_insert_non_ibss(sta);
if (err)
goto out_free;
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;
}
/* Caller must hold sta->local->sta_mtx */
int sta_info_reinsert(struct sta_info *sta)
{
struct ieee80211_local *local = sta->local;
int err = 0;
err = sta_info_insert_check(sta);
if (err) {
mutex_unlock(&local->sta_mtx);
return err;
}
might_sleep();
err = sta_info_insert_non_ibss(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 unsigned long ieee80211_tids_for_ac(int ac)
{
/* If we ever support TIDs > 7, this obviously needs to be adjusted */
switch (ac) {
case IEEE80211_AC_VO:
return BIT(6) | BIT(7);
case IEEE80211_AC_VI:
return BIT(4) | BIT(5);
case IEEE80211_AC_BE:
return BIT(0) | BIT(3);
case IEEE80211_AC_BK:
return BIT(1) | BIT(2);
default:
WARN_ON(1);
return 0;
}
}
void sta_info_recalc_tim(struct sta_info *sta)
{
struct ieee80211_local *local = sta->local;
struct ieee80211_if_ap *bss = sta->sdata->bss;
unsigned long flags;
bool indicate_tim = false;
u8 ignore_for_tim = sta->sta.uapsd_queues;
int ac;
if (WARN_ON_ONCE(!sta->sdata->bss))
return;
/* No need to do anything if the driver does all */
if (local->hw.flags & IEEE80211_HW_AP_LINK_PS)
return;
if (sta->dead)
goto done;
/*
* If all ACs are delivery-enabled then we should build
* the TIM bit for all ACs anyway; if only some are then
* we ignore those and build the TIM bit using only the
* non-enabled ones.
*/
if (ignore_for_tim == BIT(IEEE80211_NUM_ACS) - 1)
ignore_for_tim = 0;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
unsigned long tids;
if (ignore_for_tim & BIT(ac))
continue;
indicate_tim |= !skb_queue_empty(&sta->tx_filtered[ac]) ||
!skb_queue_empty(&sta->ps_tx_buf[ac]);
if (indicate_tim)
break;
tids = ieee80211_tids_for_ac(ac);
indicate_tim |=
sta->driver_buffered_tids & tids;
}
done:
spin_lock_irqsave(&local->sta_lock, flags);
if (indicate_tim)
__bss_tim_set(bss, sta->sta.aid);
else
__bss_tim_clear(bss, sta->sta.aid);
if (local->ops->set_tim) {
local->tim_in_locked_section = true;
drv_set_tim(local, &sta->sta, indicate_tim);
local->tim_in_locked_section = false;
}
spin_unlock_irqrestore(&local->sta_lock, flags);
}
static bool sta_info_buffer_expired(struct sta_info *sta, struct sk_buff *skb)
{
struct ieee80211_tx_info *info;
int timeout;
if (!skb)
return false;
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_ac(struct ieee80211_local *local,
struct sta_info *sta, int ac)
{
unsigned long flags;
struct sk_buff *skb;
/*
* First check for frames that should expire on the filtered
* queue. Frames here were rejected by the driver and are on
* a separate queue to avoid reordering with normal PS-buffered
* frames. They also aren't accounted for right now in the
* total_ps_buffered counter.
*/
for (;;) {
spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
skb = skb_peek(&sta->tx_filtered[ac]);
if (sta_info_buffer_expired(sta, skb))
skb = __skb_dequeue(&sta->tx_filtered[ac]);
else
skb = NULL;
spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
/*
* Frames are queued in order, so if this one
* hasn't expired yet we can stop testing. If
* we actually reached the end of the queue we
* also need to stop, of course.
*/
if (!skb)
break;
dev_kfree_skb(skb);
}
/*
* Now also check the normal PS-buffered queue, this will
* only find something if the filtered queue was emptied
* since the filtered frames are all before the normal PS
* buffered frames.
*/
for (;;) {
spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
skb = skb_peek(&sta->ps_tx_buf[ac]);
if (sta_info_buffer_expired(sta, skb))
skb = __skb_dequeue(&sta->ps_tx_buf[ac]);
else
skb = NULL;
spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
/*
* frames are queued in order, so if this one
* hasn't expired yet (or we reached the end of
* the queue) we can stop testing
*/
if (!skb)
break;
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);
}
/*
* Finally, recalculate the TIM bit for this station -- it might
* now be clear because the station was too slow to retrieve its
* frames.
*/
sta_info_recalc_tim(sta);
/*
* Return whether there are any frames still buffered, this is
* used to check whether the cleanup timer still needs to run,
* if there are no frames we don't need to rearm the timer.
*/
return !(skb_queue_empty(&sta->ps_tx_buf[ac]) &&
skb_queue_empty(&sta->tx_filtered[ac]));
}
static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
struct sta_info *sta)
{
bool have_buffered = false;
int ac;
/* This is only necessary for stations on BSS interfaces */
if (!sta->sdata->bss)
return false;
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
have_buffered |=
sta_info_cleanup_expire_buffered_ac(local, sta, ac);
return have_buffered;
}
static int __must_check __sta_info_destroy(struct sta_info *sta)
{
struct ieee80211_local *local;
struct ieee80211_sub_if_data *sdata;
unsigned long flags;
int ret, i, ac;
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_flag(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;
mutex_lock(&local->key_mtx);
for (i = 0; i < NUM_DEFAULT_KEYS; i++)
__ieee80211_key_free(key_mtx_dereference(local, sta->gtk[i]));
if (sta->ptk)
__ieee80211_key_free(key_mtx_dereference(local, sta->ptk));
mutex_unlock(&local->key_mtx);
sta->dead = true;
if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
BUG_ON(!sdata->bss);
clear_sta_flag(sta, WLAN_STA_PS_STA);
clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
atomic_dec(&sdata->bss->num_sta_ps);
sta_info_recalc_tim(sta);
}
local->num_sta--;
local->sta_generation++;
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
RCU_INIT_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();
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]);
__skb_queue_purge(&sta->ps_tx_buf[ac]);
__skb_queue_purge(&sta->tx_filtered[ac]);
}
#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);
cfg80211_del_sta(sdata->dev, sta->sta.addr, GFP_KERNEL);
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
__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_rx(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_rx(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;
mod_timer(&local->sta_cleanup,
round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL));
}
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);
}
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);
static void clear_sta_ps_flags(void *_sta)
{
struct sta_info *sta = _sta;
clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
clear_sta_flag(sta, WLAN_STA_PS_STA);
}
/* 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;
struct sk_buff_head pending;
int filtered = 0, buffered = 0, ac;
clear_sta_flag(sta, WLAN_STA_SP);
BUILD_BUG_ON(BITS_TO_LONGS(STA_TID_NUM) > 1);
sta->driver_buffered_tids = 0;
if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
skb_queue_head_init(&pending);
/* Send all buffered frames to the station */
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
int count = skb_queue_len(&pending), tmp;
skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending);
tmp = skb_queue_len(&pending);
filtered += tmp - count;
count = tmp;
skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending);
tmp = skb_queue_len(&pending);
buffered += tmp - count;
}
ieee80211_add_pending_skbs_fn(local, &pending, clear_sta_ps_flags, sta);
local->total_ps_buffered -= buffered;
sta_info_recalc_tim(sta);
#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,
sta->sta.addr, sta->sta.aid, filtered, buffered);
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
}
static void ieee80211_send_null_response(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta, int tid,
enum ieee80211_frame_release_type reason)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_qos_hdr *nullfunc;
struct sk_buff *skb;
int size = sizeof(*nullfunc);
__le16 fc;
bool qos = test_sta_flag(sta, WLAN_STA_WME);
struct ieee80211_tx_info *info;
if (qos) {
fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
IEEE80211_STYPE_QOS_NULLFUNC |
IEEE80211_FCTL_FROMDS);
} else {
size -= 2;
fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
IEEE80211_STYPE_NULLFUNC |
IEEE80211_FCTL_FROMDS);
}
skb = dev_alloc_skb(local->hw.extra_tx_headroom + size);
if (!skb)
return;
skb_reserve(skb, local->hw.extra_tx_headroom);
nullfunc = (void *) skb_put(skb, size);
nullfunc->frame_control = fc;
nullfunc->duration_id = 0;
memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
memcpy(nullfunc->addr2, sdata->vif.addr, ETH_ALEN);
memcpy(nullfunc->addr3, sdata->vif.addr, ETH_ALEN);
skb->priority = tid;
skb_set_queue_mapping(skb, ieee802_1d_to_ac[tid]);
if (qos) {
nullfunc->qos_ctrl = cpu_to_le16(tid);
if (reason == IEEE80211_FRAME_RELEASE_UAPSD)
nullfunc->qos_ctrl |=
cpu_to_le16(IEEE80211_QOS_CTL_EOSP);
}
info = IEEE80211_SKB_CB(skb);
/*
* Tell TX path to send this frame even though the
* STA may still remain is PS mode after this frame
* exchange. Also set EOSP to indicate this packet
* ends the poll/service period.
*/
info->flags |= IEEE80211_TX_CTL_POLL_RESPONSE |
IEEE80211_TX_STATUS_EOSP |
IEEE80211_TX_CTL_REQ_TX_STATUS;
drv_allow_buffered_frames(local, sta, BIT(tid), 1, reason, false);
ieee80211_xmit(sdata, skb);
}
static void
ieee80211_sta_ps_deliver_response(struct sta_info *sta,
int n_frames, u8 ignored_acs,
enum ieee80211_frame_release_type reason)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
bool found = false;
bool more_data = false;
int ac;
unsigned long driver_release_tids = 0;
struct sk_buff_head frames;
/* Service or PS-Poll period starts */
set_sta_flag(sta, WLAN_STA_SP);
__skb_queue_head_init(&frames);
/*
* Get response frame(s) and more data bit for it.
*/
for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
unsigned long tids;
if (ignored_acs & BIT(ac))
continue;
tids = ieee80211_tids_for_ac(ac);
if (!found) {
driver_release_tids = sta->driver_buffered_tids & tids;
if (driver_release_tids) {
found = true;
} else {
struct sk_buff *skb;
while (n_frames > 0) {
skb = skb_dequeue(&sta->tx_filtered[ac]);
if (!skb) {
skb = skb_dequeue(
&sta->ps_tx_buf[ac]);
if (skb)
local->total_ps_buffered--;
}
if (!skb)
break;
n_frames--;
found = true;
__skb_queue_tail(&frames, skb);
}
}
/*
* If the driver has data on more than one TID then
* certainly there's more data if we release just a
* single frame now (from a single TID).
*/
if (reason == IEEE80211_FRAME_RELEASE_PSPOLL &&
hweight16(driver_release_tids) > 1) {
more_data = true;
driver_release_tids =
BIT(ffs(driver_release_tids) - 1);
break;
}
}
if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
!skb_queue_empty(&sta->ps_tx_buf[ac])) {
more_data = true;
break;
}
}
if (!found) {
int tid;
/*
* For PS-Poll, this can only happen due to a race condition
* when we set the TIM bit and the station notices it, but
* before it can poll for the frame we expire it.
*
* For uAPSD, this is said in the standard (11.2.1.5 h):
* At each unscheduled SP for a non-AP STA, the AP shall
* attempt to transmit at least one MSDU or MMPDU, but no
* more than the value specified in the Max SP Length field
* in the QoS Capability element from delivery-enabled ACs,
* that are destined for the non-AP STA.
*
* Since we have no other MSDU/MMPDU, transmit a QoS null frame.
*/
/* This will evaluate to 1, 3, 5 or 7. */
tid = 7 - ((ffs(~ignored_acs) - 1) << 1);
ieee80211_send_null_response(sdata, sta, tid, reason);
return;
}
if (!driver_release_tids) {
struct sk_buff_head pending;
struct sk_buff *skb;
int num = 0;
u16 tids = 0;
skb_queue_head_init(&pending);
while ((skb = __skb_dequeue(&frames))) {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr = (void *) skb->data;
u8 *qoshdr = NULL;
num++;
/*
* 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_POLL_RESPONSE;
/*
* Use MoreData flag to indicate whether there are
* more buffered frames for this STA
*/
if (more_data || !skb_queue_empty(&frames))
hdr->frame_control |=
cpu_to_le16(IEEE80211_FCTL_MOREDATA);
else
hdr->frame_control &=
cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
if (ieee80211_is_data_qos(hdr->frame_control) ||
ieee80211_is_qos_nullfunc(hdr->frame_control))
qoshdr = ieee80211_get_qos_ctl(hdr);
/* set EOSP for the frame */
if (reason == IEEE80211_FRAME_RELEASE_UAPSD &&
qoshdr && skb_queue_empty(&frames))
*qoshdr |= IEEE80211_QOS_CTL_EOSP;
info->flags |= IEEE80211_TX_STATUS_EOSP |
IEEE80211_TX_CTL_REQ_TX_STATUS;
if (qoshdr)
tids |= BIT(*qoshdr & IEEE80211_QOS_CTL_TID_MASK);
else
tids |= BIT(0);
__skb_queue_tail(&pending, skb);
}
drv_allow_buffered_frames(local, sta, tids, num,
reason, more_data);
ieee80211_add_pending_skbs(local, &pending);
sta_info_recalc_tim(sta);
} else {
/*
* We need to release a frame that is buffered somewhere in the
* driver ... it'll have to handle that.
* Note that, as per the comment above, it'll also have to see
* if there is more than just one frame on the specific TID that
* we're releasing from, and it needs to set the more-data bit
* accordingly if we tell it that there's no more data. If we do
* tell it there's more data, then of course the more-data bit
* needs to be set anyway.
*/
drv_release_buffered_frames(local, sta, driver_release_tids,
n_frames, reason, more_data);
/*
* Note that we don't recalculate the TIM bit here as it would
* most likely have no effect at all unless the driver told us
* that the TID became empty before returning here from the
* release function.
* Either way, however, when the driver tells us that the TID
* became empty we'll do the TIM recalculation.
*/
}
}
void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta)
{
u8 ignore_for_response = sta->sta.uapsd_queues;
/*
* If all ACs are delivery-enabled then we should reply
* from any of them, if only some are enabled we reply
* only from the non-enabled ones.
*/
if (ignore_for_response == BIT(IEEE80211_NUM_ACS) - 1)
ignore_for_response = 0;
ieee80211_sta_ps_deliver_response(sta, 1, ignore_for_response,
IEEE80211_FRAME_RELEASE_PSPOLL);
}
void ieee80211_sta_ps_deliver_uapsd(struct sta_info *sta)
{
int n_frames = sta->sta.max_sp;
u8 delivery_enabled = sta->sta.uapsd_queues;
/*
* If we ever grow support for TSPEC this might happen if
* the TSPEC update from hostapd comes in between a trigger
* frame setting WLAN_STA_UAPSD in the RX path and this
* actually getting called.
*/
if (!delivery_enabled)
return;
switch (sta->sta.max_sp) {
case 1:
n_frames = 2;
break;
case 2:
n_frames = 4;
break;
case 3:
n_frames = 6;
break;
case 0:
/* XXX: what is a good value? */
n_frames = 8;
break;
}
ieee80211_sta_ps_deliver_response(sta, n_frames, ~delivery_enabled,
IEEE80211_FRAME_RELEASE_UAPSD);
}
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);
if (block)
set_sta_flag(sta, WLAN_STA_PS_DRIVER);
else if (test_sta_flag(sta, WLAN_STA_PS_DRIVER))
ieee80211_queue_work(hw, &sta->drv_unblock_wk);
}
EXPORT_SYMBOL(ieee80211_sta_block_awake);
void ieee80211_sta_eosp_irqsafe(struct ieee80211_sta *pubsta)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
struct ieee80211_local *local = sta->local;
struct sk_buff *skb;
struct skb_eosp_msg_data *data;
trace_api_eosp(local, pubsta);
skb = alloc_skb(0, GFP_ATOMIC);
if (!skb) {
/* too bad ... but race is better than loss */
clear_sta_flag(sta, WLAN_STA_SP);
return;
}
data = (void *)skb->cb;
memcpy(data->sta, pubsta->addr, ETH_ALEN);
memcpy(data->iface, sta->sdata->vif.addr, ETH_ALEN);
skb->pkt_type = IEEE80211_EOSP_MSG;
skb_queue_tail(&local->skb_queue, skb);
tasklet_schedule(&local->tasklet);
}
EXPORT_SYMBOL(ieee80211_sta_eosp_irqsafe);
void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
u8 tid, bool buffered)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
if (WARN_ON(tid >= STA_TID_NUM))
return;
if (buffered)
set_bit(tid, &sta->driver_buffered_tids);
else
clear_bit(tid, &sta->driver_buffered_tids);
sta_info_recalc_tim(sta);
}
EXPORT_SYMBOL(ieee80211_sta_set_buffered);
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