[PATCH] mac80211: Deny new BA agreements from being started during offchannel operation

["Luis R. Rodriguez" <lrodriguez@atheros.com>]

It only makes sense to allow BA agreements when we are going to
spend some time on the operating channel. This blocks all new
incoming ADDBA requests while we go offchannel, but keeps
existing BA agreements alive.

Cc: srinivasa.duvvuri@atheros.com
Cc: matt.smith@atheros.com
Cc: bennyam.malavazi@atheros.com
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
---
 net/mac80211/agg-rx.c     |    8 ++++++--
 net/mac80211/offchannel.c |   16 ++++++++++++++++
 net/mac80211/sta_info.h   |    3 ++-
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index 720b7a8..a21d120 100644
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -209,8 +209,12 @@ void ieee80211_process_addba_request(struct ieee80211_local *local,
 
 	if (test_sta_flags(sta, WLAN_STA_BLOCK_BA)) {
 #ifdef CONFIG_MAC80211_HT_DEBUG
-		printk(KERN_DEBUG "Suspend in progress. "
-		       "Denying ADDBA request\n");
+		if (local->quiescing)
+			printk(KERN_DEBUG "Suspend in progress. "
+			      "Denying ADDBA request\n");
+		else
+			printk(KERN_DEBUG "Offchannel operation in progress, "
+			      "Denying ADDBA request\n");
 #endif
 		goto end_no_lock;
 	}
diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c
index 4b56409..f3a7d2a 100644
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -34,6 +34,14 @@ static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
 
 	cancel_work_sync(&local->dynamic_ps_enable_work);
 
+	if (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) {
+		struct sta_info *sta;
+		mutex_lock(&local->sta_mtx);
+		list_for_each_entry(sta, &local->sta_list, list)
+			set_sta_flags(sta, WLAN_STA_BLOCK_BA);
+		mutex_unlock(&local->sta_mtx);
+	}
+
 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
 		local->offchannel_ps_enabled = true;
 		local->hw.conf.flags &= ~IEEE80211_CONF_PS;
@@ -92,6 +100,14 @@ static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
 
 	ieee80211_sta_reset_beacon_monitor(sdata);
 	ieee80211_sta_reset_conn_monitor(sdata);
+
+	if (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) {
+		struct sta_info *sta;
+		mutex_lock(&local->sta_mtx);
+		list_for_each_entry(sta, &local->sta_list, list)
+			clear_sta_flags(sta, WLAN_STA_BLOCK_BA);
+		mutex_unlock(&local->sta_mtx);
+	}
 }
 
 void ieee80211_offchannel_stop_beaconing(struct ieee80211_local *local)
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index cf21a2e..2439156 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -36,7 +36,8 @@
  *	frame to this station is transmitted.
  * @WLAN_STA_MFP: Management frame protection is used with this STA.
  * @WLAN_STA_BLOCK_BA: Used to deny ADDBA requests (both TX and RX)
- *	during suspend/resume and station removal.
+ *	during suspend/resume, station removal, and when we go offchannel
+ *	when associated.
  * @WLAN_STA_PS_DRIVER: driver requires keeping this station in
  *	power-save mode logically to flush frames that might still
  *	be in the queues
-- 
1.7.0.4