mac80211: Optimize scans on current operating channel.

This should decrease un-necessary flushes, on/off channel work,
and channel changes in cases where the only scanned channel is
the current operating channel.

* Removes SCAN_OFF_CHANNEL flag, uses SDATA_STATE_OFFCHANNEL
  and is-scanning flags instead.

* Add helper method to determine if we are currently configured
  for the operating channel.

* Do no blindly go off/on channel in work.c  Instead, only call
  appropriate on/off code when we really need to change channels.
  Always enable offchannel-ps mode when starting work,
  and disable it when we are done.

* Consolidate ieee80211_offchannel_stop_station and
  ieee80211_offchannel_stop_beaconing, call it
  ieee80211_offchannel_stop_vifs instead.

* Accept non-beacon frames when scanning on operating channel.

* Scan state machine optimized to minimize on/off channel
  transitions.  Also, when going on-channel, go ahead and
  re-enable beaconing.  We're going to be there for 200ms,
  so seems like some useful beaconing could happen.
  Always enable offchannel-ps mode when starting software
  scan, and disable it when we are done.

* Grab local->mtx earlier in __ieee80211_scan_completed_finish
  so that we are protected when calling hw_config(), etc.

* Pass probe-responses up the stack if scanning on local
  channel, so that mlme can take a look.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index f71ed31d176a..44eea1af1553 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -655,8 +655,6 @@ struct tpt_led_trigger {
  *      well be on the operating channel
  * @SCAN_HW_SCANNING: The hardware is scanning for us, we have no way to
  *      determine if we are on the operating channel or not
- * @SCAN_OFF_CHANNEL: We're off our operating channel for scanning,
- *      gets only set in conjunction with SCAN_SW_SCANNING
  * @SCAN_COMPLETED: Set for our scan work function when the driver reported
  *      that the scan completed.
  * @SCAN_ABORTED: Set for our scan work function when the driver reported
@@ -665,7 +663,6 @@ struct tpt_led_trigger {
 enum {
         SCAN_SW_SCANNING,
         SCAN_HW_SCANNING,
-        SCAN_OFF_CHANNEL,
         SCAN_COMPLETED,
         SCAN_ABORTED,
 };
@@ -1148,10 +1145,14 @@ void ieee80211_rx_bss_put(struct ieee80211_local *local,
                           struct ieee80211_bss *bss);
 
 /* off-channel helpers */
-void ieee80211_offchannel_stop_beaconing(struct ieee80211_local *local);
-void ieee80211_offchannel_stop_station(struct ieee80211_local *local);
+bool ieee80211_cfg_on_oper_channel(struct ieee80211_local *local);
+void ieee80211_offchannel_enable_all_ps(struct ieee80211_local *local,
+                                        bool tell_ap);
+void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
+                                    bool offchannel_ps_enable);
 void ieee80211_offchannel_return(struct ieee80211_local *local,
-                                 bool enable_beaconing);
+                                 bool enable_beaconing,
+                                 bool offchannel_ps_disable);
 void ieee80211_hw_roc_setup(struct ieee80211_local *local);
 
 /* interface handling */