mac80211: synchronize scan off/on-channel and PS states

Since:

commit b23b025fe246f3acc2988eb6d400df34c27cb8ae
Author: Ben Greear <greearb@candelatech.com>
Date:   Fri Feb 4 11:54:17 2011 -0800

    mac80211: Optimize scans on current operating channel.

we do not disable PS while going back to operational channel (on
ieee80211_scan_state_suspend) and deffer that until scan finish.
But since we are allowed to send frames, we can send a frame to AP
without PM bit set, so disable PS on AP side. Then when we switch
to off-channel (in ieee80211_scan_state_resume) we do not enable PS.
Hence we are off-channel with PS disabled, frames are not buffered
by AP.

To fix remove offchannel_ps_disable argument and always enable PS when
going off-channel and disable it when going on-channel, like it was
before.

Cc: stable@vger.kernel.org # 2.6.39+
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 8563b9a..2ed065c 100644 (file)
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1358,10 +1358,8 @@ int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata);
 void ieee80211_sched_scan_stopped_work(struct work_struct *work);
 
 /* off-channel helpers */
-void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
-                                   bool offchannel_ps_enable);
-void ieee80211_offchannel_return(struct ieee80211_local *local,
-                                bool offchannel_ps_disable);
+void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local);
+void ieee80211_offchannel_return(struct ieee80211_local *local);
 void ieee80211_roc_setup(struct ieee80211_local *local);
 void ieee80211_start_next_roc(struct ieee80211_local *local);
 void ieee80211_roc_purge(struct ieee80211_sub_if_data *sdata);

diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c
index a5379ae..a3ad4c3 100644 (file)
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -102,8 +102,7 @@ static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
        ieee80211_sta_reset_conn_monitor(sdata);
 }
 
-void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
-                                   bool offchannel_ps_enable)
+void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
 {
        struct ieee80211_sub_if_data *sdata;
 
@@ -134,8 +133,7 @@ void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
 
                if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
                        netif_tx_stop_all_queues(sdata->dev);
-                       if (offchannel_ps_enable &&
-                           (sdata->vif.type == NL80211_IFTYPE_STATION) &&
+                       if (sdata->vif.type == NL80211_IFTYPE_STATION &&
                            sdata->u.mgd.associated)
                                ieee80211_offchannel_ps_enable(sdata);
                }
@@ -143,8 +141,7 @@ void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
        mutex_unlock(&local->iflist_mtx);
 }
 
-void ieee80211_offchannel_return(struct ieee80211_local *local,
-                                bool offchannel_ps_disable)
+void ieee80211_offchannel_return(struct ieee80211_local *local)
 {
        struct ieee80211_sub_if_data *sdata;
 
@@ -163,11 +160,9 @@ void ieee80211_offchannel_return(struct ieee80211_local *local,
                        continue;
 
                /* Tell AP we're back */
-               if (offchannel_ps_disable &&
-                   sdata->vif.type == NL80211_IFTYPE_STATION) {
-                       if (sdata->u.mgd.associated)
-                               ieee80211_offchannel_ps_disable(sdata);
-               }
+               if (sdata->vif.type == NL80211_IFTYPE_STATION &&
+                   sdata->u.mgd.associated)
+                       ieee80211_offchannel_ps_disable(sdata);
 
                if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
                        /*
@@ -385,7 +380,7 @@ void ieee80211_sw_roc_work(struct work_struct *work)
                        local->tmp_channel = NULL;
                        ieee80211_hw_config(local, 0);
 
-                       ieee80211_offchannel_return(local, true);
+                       ieee80211_offchannel_return(local);
                }
 
                ieee80211_recalc_idle(local);

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index d59fc68..bf82e69 100644 (file)
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -292,7 +292,7 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted,
        if (!was_hw_scan) {
                ieee80211_configure_filter(local);
                drv_sw_scan_complete(local);
-               ieee80211_offchannel_return(local, true);
+               ieee80211_offchannel_return(local);
        }
 
        ieee80211_recalc_idle(local);
@@ -341,7 +341,7 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local)
        local->next_scan_state = SCAN_DECISION;
        local->scan_channel_idx = 0;
 
-       ieee80211_offchannel_stop_vifs(local, true);
+       ieee80211_offchannel_stop_vifs(local);
 
        ieee80211_configure_filter(local);
 
@@ -678,12 +678,8 @@ static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
        local->scan_channel = NULL;
        ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 
-       /*
-        * Re-enable vifs and beaconing.  Leave PS
-        * in off-channel state..will put that back
-        * on-channel at the end of scanning.
-        */
-       ieee80211_offchannel_return(local, false);
+       /* disable PS */
+       ieee80211_offchannel_return(local);
 
        *next_delay = HZ / 5;
        /* afterwards, resume scan & go to next channel */
@@ -693,8 +689,7 @@ static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
                                        unsigned long *next_delay)
 {
-       /* PS already is in off-channel mode */
-       ieee80211_offchannel_stop_vifs(local, false);
+       ieee80211_offchannel_stop_vifs(local);
 
        if (local->ops->flush) {
                drv_flush(local, false);