mac80211: TDLS: correctly configure SMPS state

The IEEE802.11-2012 specification is vague regarding SMPS operation during
TDLS. It does not define a clear way to transition between SMPS states.

To avoid interop issues, set SMPS to off when TDLS peers are connected.
Accomplish this by extending the definition of the AUTOMATIC state. If the
driver forces a state other than OFF, disconnect all TDLS peers.

While at it, avoid changing the SMPS state of the peer STA. We have no
way to control it, so try and behave correctly towards it.

Move the TDLS peer-teardown function to where the rest of the TDLS code
resides.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index a32575bf05465d39aad1150765100c85a331d2cb..5789d83535059deaeef2193ea29bfdc0adab9357 100644 (file)
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2368,6 +2368,8 @@ int __ieee80211_request_smps_mgd(struct ieee80211_sub_if_data *sdata,
        const u8 *ap;
        enum ieee80211_smps_mode old_req;
        int err;
+       struct sta_info *sta;
+       bool tdls_peer_found = false;
 
        lockdep_assert_held(&sdata->wdev.mtx);
 
@@ -2392,11 +2394,22 @@ int __ieee80211_request_smps_mgd(struct ieee80211_sub_if_data *sdata,
 
        ap = sdata->u.mgd.associated->bssid;
 
+       rcu_read_lock();
+       list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
+               if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
+                   !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
+                       continue;
+
+               tdls_peer_found = true;
+               break;
+       }
+       rcu_read_unlock();
+
        if (smps_mode == IEEE80211_SMPS_AUTOMATIC) {
-               if (sdata->u.mgd.powersave)
-                       smps_mode = IEEE80211_SMPS_DYNAMIC;
-               else
+               if (tdls_peer_found || !sdata->u.mgd.powersave)
                        smps_mode = IEEE80211_SMPS_OFF;
+               else
+                       smps_mode = IEEE80211_SMPS_DYNAMIC;
        }
 
        /* send SM PS frame to AP */
@@ -2404,6 +2417,8 @@ int __ieee80211_request_smps_mgd(struct ieee80211_sub_if_data *sdata,
                                         ap, ap);
        if (err)
                sdata->u.mgd.req_smps = old_req;
+       else if (smps_mode != IEEE80211_SMPS_OFF && tdls_peer_found)
+               ieee80211_teardown_tdls_peers(sdata);
 
        return err;
 }

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 6376c673a9fecd54ac5ed3dca9bd41f3c58222fe..dd131e9b41d7e0ec20df22662a9abd5f0ac636a4 100644 (file)
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -2054,6 +2054,7 @@ void ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
                                          const u8 *addr);
 void ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
                                           struct sk_buff *skb);
+void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata);
 
 extern const struct ethtool_ops ieee80211_ethtool_ops;
 

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index ae5d6c48272d144e022affbeaadd44522e05ceaf..6332ff705ec3819a4c2bb4e11c35ba965658f6df 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1096,24 +1096,6 @@ static void ieee80211_chswitch_timer(unsigned long data)
        ieee80211_queue_work(&sdata->local->hw, &sdata->u.mgd.chswitch_work);
 }
 
-static void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
-{
-       struct sta_info *sta;
-       u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
-
-       rcu_read_lock();
-       list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
-               if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
-                   !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
-                       continue;
-
-               ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
-                                           NL80211_TDLS_TEARDOWN, reason,
-                                           GFP_ATOMIC);
-       }
-       rcu_read_unlock();
-}
-
 static void
 ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
                                 u64 timestamp, u32 device_timestamp,

diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c
index fb846cb047d6c92cb3b949ecd61e0dabcb5fa58f..8536789da17d2b7a25ae99fdf98c11d5a7e6d0c9 100644 (file)
--- a/net/mac80211/tdls.c
+++ b/net/mac80211/tdls.c
@@ -4,6 +4,7 @@
  * Copyright 2006-2010 Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2014, Intel Corporation
  * Copyright 2014  Intel Mobile Communications GmbH
+ * Copyright 2015  Intel Deutschland GmbH
  *
  * This file is GPLv2 as found in COPYING.
  */
@@ -448,10 +449,6 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
                ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
        } else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
                   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
-               /* disable SMPS in TDLS responder */
-               sta->sta.ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
-                                       << IEEE80211_HT_CAP_SM_PS_SHIFT;
-
                /* the peer caps are already intersected with our own */
                memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
 
@@ -1063,8 +1060,17 @@ ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
 {
        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
        struct ieee80211_local *local = sdata->local;
+       enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
        int ret;
 
+       /* don't support setup with forced SMPS mode that's not off */
+       if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
+           smps_mode != IEEE80211_SMPS_OFF) {
+               tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
+                        smps_mode);
+               return -ENOTSUPP;
+       }
+
        mutex_lock(&local->mtx);
 
        /* we don't support concurrent TDLS peer setups */
@@ -1323,6 +1329,10 @@ int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
                eth_zero_addr(sdata->u.mgd.tdls_peer);
        }
 
+       if (ret == 0)
+               ieee80211_queue_work(&sdata->local->hw,
+                                    &sdata->u.mgd.request_smps_work);
+
        mutex_unlock(&local->mtx);
        return ret;
 }
@@ -1819,3 +1829,21 @@ void ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
                return;
        }
 }
+
+void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
+{
+       struct sta_info *sta;
+       u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
+               if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
+                   !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
+                       continue;
+
+               ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
+                                           NL80211_TDLS_TEARDOWN, reason,
+                                           GFP_ATOMIC);
+       }
+       rcu_read_unlock();
+}