wifi: mac80211: handle netif carrier up/down with link AP during MLO

Currently whenever link AP is started, netif_carrier_up() function is
called and whenever it is brought down, netif_carrier_down() function is
called. However, with MLO, all the links of the same MLD would use the
same netdev. Hence there is no need to indicate for each link up/down.
Also, calling it down when only one of the links went down is not
desirable.

Add changes to call the netif_carrier_up() function only when first link
is brought up. Similarly, add changes to call the netif_carrier_down()
function only when last link is brought down.

In order to check the number of beaconing links in the given interface,
introduce a new helper function ieee80211_num_beaconing_links().

Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Link: https://msgid.link/20240227042251.1511122-3-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index bc0c1300e4047c6bb1520b96b639ad94459c9dd3..734368fd3f97f6605f592bc49c54789751ac9f84 100644 (file)
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1241,6 +1241,30 @@ ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
        return 0;
 }
 
+static u8 ieee80211_num_beaconing_links(struct ieee80211_sub_if_data *sdata)
+{
+       struct ieee80211_link_data *link;
+       u8 link_id, num = 0;
+
+       if (sdata->vif.type != NL80211_IFTYPE_AP &&
+           sdata->vif.type != NL80211_IFTYPE_P2P_GO)
+               return num;
+
+       if (!sdata->vif.valid_links)
+               return num;
+
+       for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
+               link = sdata_dereference(sdata->link[link_id], sdata);
+               if (!link)
+                       continue;
+
+               if (sdata_dereference(link->u.ap.beacon, sdata))
+                       num++;
+       }
+
+       return num;
+}
+
 static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
                              struct cfg80211_ap_settings *params)
 {
@@ -1470,7 +1494,9 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
        ieee80211_vif_cfg_change_notify(sdata, BSS_CHANGED_SSID);
        ieee80211_link_info_change_notify(sdata, link, changed);
 
-       netif_carrier_on(dev);
+       if (ieee80211_num_beaconing_links(sdata) <= 1)
+               netif_carrier_on(dev);
+
        list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
                netif_carrier_on(vlan->dev);
 
@@ -1592,7 +1618,9 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev,
        /* turn off carrier for this interface and dependent VLANs */
        list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
                netif_carrier_off(vlan->dev);
-       netif_carrier_off(dev);
+
+       if (ieee80211_num_beaconing_links(sdata) <= 1)
+               netif_carrier_off(dev);
 
        /* remove beacon and probe response */
        sdata->u.ap.active = false;