mac80211: batch CSA bss info notification

Instead of having
ieee80211_bss_info_change_notify() scattered all
over the place just call it once when finalizing
CSA.

As a side effect this patch adds missing error
checking for IBSS CSA beacon update.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Reviewed-by: Luciano Coelho <luciano.coelho@intel.com>
[fix err vs. changed variable usage in ieee80211_csa_finalize()]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/cfg.c

@@ -3014,29 +3014,28 @@ static void ieee80211_csa_finalize(struct ieee80211_sub_if_data *sdata)
 		ieee80211_hw_config(local, 0);
 	}
 
-	ieee80211_bss_info_change_notify(sdata, changed);
-
 	sdata->vif.csa_active = false;
 	switch (sdata->vif.type) {
 	case NL80211_IFTYPE_AP:
 		err = ieee80211_assign_beacon(sdata, sdata->u.ap.next_beacon);
 		if (err < 0)
 			return;
-
 		changed |= err;
 		kfree(sdata->u.ap.next_beacon);
 		sdata->u.ap.next_beacon = NULL;
-
-		ieee80211_bss_info_change_notify(sdata, err);
 		break;
 	case NL80211_IFTYPE_ADHOC:
-		ieee80211_ibss_finish_csa(sdata);
+		err = ieee80211_ibss_finish_csa(sdata);
+		if (err < 0)
+			return;
+		changed |= err;
 		break;
 #ifdef CONFIG_MAC80211_MESH
 	case NL80211_IFTYPE_MESH_POINT:
 		err = ieee80211_mesh_finish_csa(sdata);
 		if (err < 0)
 			return;
+		changed |= err;
 		break;
 #endif
 	default:
@@ -3044,6 +3043,8 @@ static void ieee80211_csa_finalize(struct ieee80211_sub_if_data *sdata)
 		return;
 	}
 
+	ieee80211_bss_info_change_notify(sdata, changed);
+
 	ieee80211_wake_queues_by_reason(&sdata->local->hw,
 					IEEE80211_MAX_QUEUE_MAP,
 					IEEE80211_QUEUE_STOP_REASON_CSA);

net/mac80211/ibss.c

@@ -530,7 +530,7 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 	struct cfg80211_bss *cbss;
-	int err;
+	int err, changed = 0;
 	u16 capability;
 
 	sdata_assert_lock(sdata);
@@ -562,10 +562,9 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 	if (err < 0)
 		return err;
 
-	if (err)
-		ieee80211_bss_info_change_notify(sdata, err);
+	changed |= err;
 
-	return 0;
+	return changed;
 }
 
 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)

net/mac80211/mesh.c

@@ -1058,6 +1058,7 @@ int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct mesh_csa_settings *tmp_csa_settings;
 	int ret = 0;
+	int changed = 0;
 
 	/* Reset the TTL value and Initiator flag */
 	ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
@@ -1072,11 +1073,11 @@ int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
 	if (ret)
 		return -EINVAL;
 
-	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
+	changed |= BSS_CHANGED_BEACON;
 
 	mcsa_dbg(sdata, "complete switching to center freq %d MHz",
 		 sdata->vif.bss_conf.chandef.chan->center_freq);
-	return 0;
+	return changed;
 }
 
 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,