mac80211: notify the driver when a sta uses 4-address mode

This is needed for encapsulation offload of 4-address mode packets
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20200908123702.88454-14-nbd@nbd.nameSigned-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -3842,6 +3842,8 @@ enum ieee80211_reconfig_type {
  *	This callback may sleep.
  * @update_vif_config: Update virtual interface offload flags
  *	This callback may sleep.
+ * @sta_set_4addr: Called to notify the driver when a station starts/stops using
+ *	4-address mode
  */
 struct ieee80211_ops {
 	void (*tx)(struct ieee80211_hw *hw,
@@ -4155,6 +4157,8 @@ struct ieee80211_ops {
 				struct ieee80211_sta *sta, u8 tids);
 	void (*update_vif_offload)(struct ieee80211_hw *hw,
 				   struct ieee80211_vif *vif);
+	void (*sta_set_4addr)(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+			      struct ieee80211_sta *sta, bool enabled);
 };
 
 /**

net/mac80211/cfg.c

@@ -1696,6 +1696,7 @@ static int ieee80211_change_station(struct wiphy *wiphy,
 
 			rcu_assign_pointer(vlansdata->u.vlan.sta, sta);
 			__ieee80211_check_fast_rx_iface(vlansdata);
+			drv_sta_set_4addr(local, sta->sdata, &sta->sta, true);
 		}
 
 		if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&

net/mac80211/driver-ops.h

@@ -1399,4 +1399,18 @@ static inline void drv_update_vif_offload(struct ieee80211_local *local,
 	trace_drv_return_void(local);
 }
 
+static inline void drv_sta_set_4addr(struct ieee80211_local *local,
+				     struct ieee80211_sub_if_data *sdata,
+				     struct ieee80211_sta *sta, bool enabled)
+{
+	sdata = get_bss_sdata(sdata);
+	if (!check_sdata_in_driver(sdata))
+		return;
+
+	trace_drv_sta_set_4addr(local, sdata, sta, enabled);
+	if (local->ops->sta_set_4addr)
+		local->ops->sta_set_4addr(&local->hw, &sdata->vif, sta, enabled);
+	trace_drv_return_void(local);
+}
+
 #endif /* __MAC80211_DRIVER_OPS */

net/mac80211/mlme.c

@@ -3548,6 +3548,9 @@ static bool ieee80211_assoc_success(struct ieee80211_sub_if_data *sdata,
 		goto out;
 	}
 
+	if (sdata->wdev.use_4addr)
+		drv_sta_set_4addr(local, sdata, &sta->sta, true);
+
 	mutex_unlock(&sdata->local->sta_mtx);
 
 	/*

net/mac80211/trace.h

@@ -2740,6 +2740,33 @@ DEFINE_EVENT(local_sdata_addr_evt, drv_update_vif_offload,
 	TP_ARGS(local, sdata)
 );
 
+TRACE_EVENT(drv_sta_set_4addr,
+	TP_PROTO(struct ieee80211_local *local,
+		 struct ieee80211_sub_if_data *sdata,
+		 struct ieee80211_sta *sta, bool enabled),
+
+	TP_ARGS(local, sdata, sta, enabled),
+
+	TP_STRUCT__entry(
+		LOCAL_ENTRY
+		VIF_ENTRY
+		STA_ENTRY
+		__field(bool, enabled)
+	),
+
+	TP_fast_assign(
+		LOCAL_ASSIGN;
+		VIF_ASSIGN;
+		STA_ASSIGN;
+		__entry->enabled = enabled;
+	),
+
+	TP_printk(
+		LOCAL_PR_FMT  VIF_PR_FMT  STA_PR_FMT " enabled:%d",
+		LOCAL_PR_ARG, VIF_PR_ARG, STA_PR_ARG, __entry->enabled
+	)
+);
+
 #endif /* !__MAC80211_DRIVER_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH