wifi: mac80211: replace link_id with link_conf in start/stop_ap()

When calling start/stop_ap(), mac80211 already has a protected
link_conf pointer. Pass it to the driver, so it shouldn't
handle RCU protection.
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c

@@ -2397,7 +2397,7 @@ static void iwl_mvm_bss_info_changed_station(struct iwl_mvm *mvm,
 
 static int iwl_mvm_start_ap_ibss(struct ieee80211_hw *hw,
 				 struct ieee80211_vif *vif,
-				 unsigned int link_id)
+				 struct ieee80211_bss_conf *link_conf)
 {
 	struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
@@ -2525,20 +2525,20 @@ static int iwl_mvm_start_ap_ibss(struct ieee80211_hw *hw,
 
 static int iwl_mvm_start_ap(struct ieee80211_hw *hw,
 			    struct ieee80211_vif *vif,
-			    unsigned int link_id)
+			    struct ieee80211_bss_conf *link_conf)
 {
-	return iwl_mvm_start_ap_ibss(hw, vif, link_id);
+	return iwl_mvm_start_ap_ibss(hw, vif, link_conf);
 }
 
 static int iwl_mvm_start_ibss(struct ieee80211_hw *hw,
 			      struct ieee80211_vif *vif)
 {
-	return iwl_mvm_start_ap_ibss(hw, vif, 0);
+	return iwl_mvm_start_ap_ibss(hw, vif, &vif->bss_conf);
 }
 
 static void iwl_mvm_stop_ap_ibss(struct ieee80211_hw *hw,
 				 struct ieee80211_vif *vif,
-				 unsigned int link_id)
+				 struct ieee80211_bss_conf *link_conf)
 {
 	struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
@@ -2603,15 +2603,15 @@ static void iwl_mvm_stop_ap_ibss(struct ieee80211_hw *hw,
 
 static void iwl_mvm_stop_ap(struct ieee80211_hw *hw,
 			    struct ieee80211_vif *vif,
-			    unsigned int link_id)
+			    struct ieee80211_bss_conf *link_conf)
 {
-	iwl_mvm_stop_ap_ibss(hw, vif, link_id);
+	iwl_mvm_stop_ap_ibss(hw, vif, link_conf);
 }
 
 static void iwl_mvm_stop_ibss(struct ieee80211_hw *hw,
 			      struct ieee80211_vif *vif)
 {
-	iwl_mvm_stop_ap_ibss(hw, vif, 0);
+	iwl_mvm_stop_ap_ibss(hw, vif, &vif->bss_conf);
 }
 
 static void

drivers/net/wireless/realtek/rtw88/mac80211.c

@@ -430,7 +430,8 @@ static void rtw_ops_bss_info_changed(struct ieee80211_hw *hw,
 }
 
 static int rtw_ops_start_ap(struct ieee80211_hw *hw,
-			    struct ieee80211_vif *vif, unsigned int link_id)
+			    struct ieee80211_vif *vif,
+			    struct ieee80211_bss_conf *link_conf)
 {
 	struct rtw_dev *rtwdev = hw->priv;
 	struct rtw_chip_info *chip = rtwdev->chip;

drivers/net/wireless/realtek/rtw89/mac80211.c

@@ -382,7 +382,8 @@ static void rtw89_ops_bss_info_changed(struct ieee80211_hw *hw,
 }
 
 static int rtw89_ops_start_ap(struct ieee80211_hw *hw,
-			      struct ieee80211_vif *vif, unsigned int link_id)
+			      struct ieee80211_vif *vif,
+			      struct ieee80211_bss_conf *link_conf)
 {
 	struct rtw89_dev *rtwdev = hw->priv;
 	struct rtw89_vif *rtwvif = (struct rtw89_vif *)vif->drv_priv;
@@ -403,7 +404,7 @@ static int rtw89_ops_start_ap(struct ieee80211_hw *hw,
 
 static
 void rtw89_ops_stop_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
-		       unsigned int link_id)
+		       struct ieee80211_bss_conf *link_conf)
 {
 	struct rtw89_dev *rtwdev = hw->priv;
 	struct rtw89_vif *rtwvif = (struct rtw89_vif *)vif->drv_priv;

drivers/net/wireless/silabs/wfx/sta.c

@@ -380,7 +380,7 @@ static void wfx_set_mfp_ap(struct wfx_vif *wvif)
 }
 
 int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
-		 unsigned int link_id)
+		 struct ieee80211_bss_conf *link_conf)
 {
 	struct wfx_vif *wvif = (struct wfx_vif *)vif->drv_priv;
 	struct wfx_dev *wdev = wvif->wdev;
@@ -399,7 +399,7 @@ int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 }
 
 void wfx_stop_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
-		 unsigned int link_id)
+		 struct ieee80211_bss_conf *link_conf)
 {
 	struct wfx_vif *wvif = (struct wfx_vif *)vif->drv_priv;
 

drivers/net/wireless/silabs/wfx/sta.h

@@ -30,9 +30,9 @@ void wfx_configure_filter(struct ieee80211_hw *hw, unsigned int changed_flags,
 int wfx_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
 void wfx_remove_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
 int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
-		 unsigned int link_id);
+		 struct ieee80211_bss_conf *link_conf);
 void wfx_stop_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
-		 unsigned int link_id);
+		 struct ieee80211_bss_conf *link_conf);
 int wfx_join_ibss(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
 void wfx_leave_ibss(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
 int wfx_conf_tx(struct ieee80211_hw *hw, struct ieee80211_vif *vif,

include/net/mac80211.h

@@ -4092,9 +4092,9 @@ struct ieee80211_ops {
 				  u64 changed);
 
 	int (*start_ap)(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
-			unsigned int link_id);
+			struct ieee80211_bss_conf *link_conf);
 	void (*stop_ap)(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
-			unsigned int link_id);
+			struct ieee80211_bss_conf *link_conf);
 
 	u64 (*prepare_multicast)(struct ieee80211_hw *hw,
 				 struct netdev_hw_addr_list *mc_list);

net/mac80211/cfg.c

@@ -1296,7 +1296,7 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 		changed |= BSS_CHANGED_UNSOL_BCAST_PROBE_RESP;
 	}
 
-	err = drv_start_ap(sdata->local, sdata, link_id);
+	err = drv_start_ap(sdata->local, sdata, link_conf);
 	if (err) {
 		old = sdata_dereference(link->u.ap.beacon, sdata);
 
@@ -1457,7 +1457,7 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev,
 				   GFP_KERNEL);
 	}
 
-	drv_stop_ap(sdata->local, sdata, link_id);
+	drv_stop_ap(sdata->local, sdata, link_conf);
 
 	/* free all potentially still buffered bcast frames */
 	local->total_ps_buffered -= skb_queue_len(&sdata->u.ap.ps.bc_buf);

net/mac80211/driver-ops.h

@@ -987,32 +987,38 @@ int drv_switch_vif_chanctx(struct ieee80211_local *local,
 
 static inline int drv_start_ap(struct ieee80211_local *local,
 			       struct ieee80211_sub_if_data *sdata,
-			       unsigned int link_id)
+			       struct ieee80211_bss_conf *link_conf)
 {
 	int ret = 0;
 
+	/* make sure link_conf is protected */
+	sdata_assert_lock(sdata);
+
 	might_sleep();
 
 	if (!check_sdata_in_driver(sdata))
 		return -EIO;
 
-	trace_drv_start_ap(local, sdata, link_id);
+	trace_drv_start_ap(local, sdata, link_conf);
 	if (local->ops->start_ap)
-		ret = local->ops->start_ap(&local->hw, &sdata->vif, link_id);
+		ret = local->ops->start_ap(&local->hw, &sdata->vif, link_conf);
 	trace_drv_return_int(local, ret);
 	return ret;
 }
 
 static inline void drv_stop_ap(struct ieee80211_local *local,
 			       struct ieee80211_sub_if_data *sdata,
-			       unsigned int link_id)
+			       struct ieee80211_bss_conf *link_conf)
 {
+	/* make sure link_conf is protected */
+	sdata_assert_lock(sdata);
+
 	if (!check_sdata_in_driver(sdata))
 		return;
 
-	trace_drv_stop_ap(local, sdata, link_id);
+	trace_drv_stop_ap(local, sdata, link_conf);
 	if (local->ops->stop_ap)
-		local->ops->stop_ap(&local->hw, &sdata->vif, link_id);
+		local->ops->stop_ap(&local->hw, &sdata->vif, link_conf);
 	trace_drv_return_void(local);
 }
 

net/mac80211/trace.h

@@ -1754,9 +1754,9 @@ DEFINE_EVENT(local_sdata_chanctx, drv_unassign_vif_chanctx,
 TRACE_EVENT(drv_start_ap,
 	TP_PROTO(struct ieee80211_local *local,
 		 struct ieee80211_sub_if_data *sdata,
-		 unsigned int link_id),
+		 struct ieee80211_bss_conf *link_conf),
 
-	TP_ARGS(local, sdata, link_id),
+	TP_ARGS(local, sdata, link_conf),
 
 	TP_STRUCT__entry(
 		LOCAL_ENTRY
@@ -1769,17 +1769,12 @@ TRACE_EVENT(drv_start_ap,
 	),
 
 	TP_fast_assign(
-		struct ieee80211_bss_conf *info =
-			sdata_dereference(sdata->vif.link_conf[link_id], sdata);
-
 		LOCAL_ASSIGN;
 		VIF_ASSIGN;
-		__entry->link_id = link_id;
-		if (info) {
-			__entry->dtimper = info->dtim_period;
-			__entry->bcnint = info->beacon_int;
-			__entry->hidden_ssid = info->hidden_ssid;
-		}
+		__entry->link_id = link_conf->link_id;
+		__entry->dtimper = link_conf->dtim_period;
+		__entry->bcnint = link_conf->beacon_int;
+		__entry->hidden_ssid = link_conf->hidden_ssid;
 		memcpy(__get_dynamic_array(ssid),
 		       sdata->vif.cfg.ssid,
 		       sdata->vif.cfg.ssid_len);
@@ -1794,9 +1789,9 @@ TRACE_EVENT(drv_start_ap,
 TRACE_EVENT(drv_stop_ap,
 	TP_PROTO(struct ieee80211_local *local,
 		 struct ieee80211_sub_if_data *sdata,
-		 unsigned int link_id),
+		 struct ieee80211_bss_conf *link_conf),
 
-	TP_ARGS(local, sdata, link_id),
+	TP_ARGS(local, sdata, link_conf),
 
 	TP_STRUCT__entry(
 		LOCAL_ENTRY
@@ -1807,7 +1802,7 @@ TRACE_EVENT(drv_stop_ap,
 	TP_fast_assign(
 		LOCAL_ASSIGN;
 		VIF_ASSIGN;
-		__entry->link_id = link_id;
+		__entry->link_id = link_conf->link_id;
 	),
 
 	TP_printk(

net/mac80211/util.c

@@ -2579,7 +2579,8 @@ int ieee80211_reconfig(struct ieee80211_local *local)
 				changed |= BSS_CHANGED_AP_PROBE_RESP;
 
 				if (rcu_access_pointer(sdata->deflink.u.ap.beacon))
-					drv_start_ap(local, sdata, 0);
+					drv_start_ap(local, sdata,
+						     sdata->deflink.conf);
 			}
 			fallthrough;
 		case NL80211_IFTYPE_MESH_POINT: