wifi: iwlwifi: mvm: add MLO support to SF - use sta pointer

For MLO support, use the pointer to the peer MLD instead of the default
link station id, since the default link is only used for non-MLO cases.
Using the default link sta id is meaningless for MLO. Also remove the
rcu protected section since we now avoid the lookup based on sta id.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230417113648.40cef48c0592.I8dd666d603d6e1854033e5369c70e78d9303d236@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

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

@@ -8,7 +8,7 @@
 /* For counting bound interfaces */
 struct iwl_mvm_active_iface_iterator_data {
 	struct ieee80211_vif *ignore_vif;
-	u8 sta_vif_ap_sta_id;
+	struct ieee80211_sta *sta_vif_ap_sta;
 	enum iwl_sf_state sta_vif_state;
 	u32 num_active_macs;
 };
@@ -30,7 +30,7 @@ static void iwl_mvm_bound_iface_iterator(void *_data, u8 *mac,
 	data->num_active_macs++;
 
 	if (vif->type == NL80211_IFTYPE_STATION) {
-		data->sta_vif_ap_sta_id = mvmvif->deflink.ap_sta_id;
+		data->sta_vif_ap_sta = mvmvif->ap_sta;
 		if (vif->cfg.assoc)
 			data->sta_vif_state = SF_FULL_ON;
 		else
@@ -172,13 +172,12 @@ static void iwl_mvm_fill_sf_command(struct iwl_mvm *mvm,
 	}
 }
 
-static int iwl_mvm_sf_config(struct iwl_mvm *mvm, u8 sta_id,
+static int iwl_mvm_sf_config(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
 			     enum iwl_sf_state new_state)
 {
 	struct iwl_sf_cfg_cmd sf_cmd = {
 		.state = cpu_to_le32(new_state),
 	};
-	struct ieee80211_sta *sta;
 	int ret = 0;
 
 	if (mvm->cfg->disable_dummy_notification)
@@ -196,20 +195,12 @@ static int iwl_mvm_sf_config(struct iwl_mvm *mvm, u8 sta_id,
 		iwl_mvm_fill_sf_command(mvm, &sf_cmd, NULL);
 		break;
 	case SF_FULL_ON:
-		if (sta_id == IWL_MVM_INVALID_STA) {
+		if (!sta) {
 			IWL_ERR(mvm,
 				"No station: Cannot switch SF to FULL_ON\n");
 			return -EINVAL;
 		}
-		rcu_read_lock();
-		sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]);
-		if (IS_ERR_OR_NULL(sta)) {
-			IWL_ERR(mvm, "Invalid station id\n");
-			rcu_read_unlock();
-			return -EINVAL;
-		}
 		iwl_mvm_fill_sf_command(mvm, &sf_cmd, sta);
-		rcu_read_unlock();
 		break;
 	case SF_INIT_OFF:
 		iwl_mvm_fill_sf_command(mvm, &sf_cmd, NULL);
@@ -237,13 +228,12 @@ int iwl_mvm_sf_update(struct iwl_mvm *mvm, struct ieee80211_vif *changed_vif,
 		      bool remove_vif)
 {
 	enum iwl_sf_state new_state;
-	u8 sta_id = IWL_MVM_INVALID_STA;
 	struct iwl_mvm_vif *mvmvif = NULL;
 	struct iwl_mvm_active_iface_iterator_data data = {
 		.ignore_vif = changed_vif,
 		.sta_vif_state = SF_UNINIT,
-		.sta_vif_ap_sta_id = IWL_MVM_INVALID_STA,
 	};
+	struct ieee80211_sta *sta = NULL;
 
 	/*
 	 * Ignore the call if we are in HW Restart flow, or if the handled
@@ -273,7 +263,7 @@ int iwl_mvm_sf_update(struct iwl_mvm *mvm, struct ieee80211_vif *changed_vif,
 			 * and we filled the relevant data during iteration
 			 */
 			new_state = data.sta_vif_state;
-			sta_id = data.sta_vif_ap_sta_id;
+			sta = data.sta_vif_ap_sta;
 		} else {
 			if (WARN_ON(!changed_vif))
 				return -EINVAL;
@@ -282,7 +272,7 @@ int iwl_mvm_sf_update(struct iwl_mvm *mvm, struct ieee80211_vif *changed_vif,
 			} else if (changed_vif->cfg.assoc &&
 				   changed_vif->bss_conf.dtim_period) {
 				mvmvif = iwl_mvm_vif_from_mac80211(changed_vif);
-				sta_id = mvmvif->deflink.ap_sta_id;
+				sta = mvmvif->ap_sta;
 				new_state = SF_FULL_ON;
 			} else {
 				new_state = SF_INIT_OFF;
@@ -294,8 +284,5 @@ int iwl_mvm_sf_update(struct iwl_mvm *mvm, struct ieee80211_vif *changed_vif,
 		new_state = SF_UNINIT;
 	}
 
-	/* For MLO it's ok to use deflink->sta_id as it's needed only to get
-	 * a pointer to mac80211 sta
-	 */
-	return iwl_mvm_sf_config(mvm, sta_id, new_state);
+	return iwl_mvm_sf_config(mvm, sta, new_state);
 }