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>

1 files changed, 5 insertions, 10 deletions

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index d59fc6818b1c..bf82e69d0601 100644
--- 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);