wifi: mac80211: Create separate links for VLAN interfaces

Currently, MLD links for an AP_VLAN interface type is not fully
supported.

Add allocation of separate links for each VLAN interface and copy
chanctx and chandef of AP bss to VLAN where necessary. Separate
links are created because for Dynamic VLAN each link will have its own
default_multicast_key.

Signed-off-by: Muna Sinada <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Johannes Berg <[e-mail]>

net/mac80211/chan.c

···
 {
 	struct ieee80211_sub_if_data *sdata = link->sdata;
 
+	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
+		return;
+
 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
 
 	if (rcu_access_pointer(link->conf->chanctx_conf))

net/mac80211/ieee80211_i.h

···
 	ieee80211_vif_set_links(sdata, 0, 0);
 }
 
+void ieee80211_apvlan_link_setup(struct ieee80211_sub_if_data *sdata);
+void ieee80211_apvlan_link_clear(struct ieee80211_sub_if_data *sdata);
+
 /* tx handling */
 void ieee80211_clear_tx_pending(struct ieee80211_local *local);
 void ieee80211_tx_pending(struct tasklet_struct *t);

net/mac80211/iface.c

···
 	case NL80211_IFTYPE_MONITOR:
 		list_del_rcu(&sdata->u.mntr.list);
 		break;
+	case NL80211_IFTYPE_AP_VLAN:
+		ieee80211_apvlan_link_clear(sdata);
+		break;
 	default:
 		break;
 	}
···
 		sdata->crypto_tx_tailroom_needed_cnt +=
 			master->crypto_tx_tailroom_needed_cnt;
 
+		ieee80211_apvlan_link_setup(sdata);
+
 		break;
 		}
 	case NL80211_IFTYPE_AP:
···
 	case NL80211_IFTYPE_AP_VLAN:
 		/* no need to tell driver, but set carrier and chanctx */
 		if (sdata->bss->active) {
-			ieee80211_link_vlan_copy_chanctx(&sdata->deflink);
+			struct ieee80211_link_data *link;
+
+			for_each_link_data(sdata, link) {
+				ieee80211_link_vlan_copy_chanctx(link);
+			}
+
 			netif_carrier_on(dev);
 			ieee80211_set_vif_encap_ops(sdata);
 		} else {

net/mac80211/link.c

···
 #include "key.h"
 #include "debugfs_netdev.h"
 
+static void ieee80211_update_apvlan_links(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_sub_if_data *vlan;
+	struct ieee80211_link_data *link;
+	u16 ap_bss_links = sdata->vif.valid_links;
+	u16 new_links, vlan_links;
+	unsigned long add;
+
+	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
+		int link_id;
+
+		if (!vlan)
+			continue;
+
+		/* No support for 4addr with MLO yet */
+		if (vlan->wdev.use_4addr)
+			return;
+
+		vlan_links = vlan->vif.valid_links;
+
+		new_links = ap_bss_links;
+
+		add = new_links & ~vlan_links;
+		if (!add)
+			continue;
+
+		ieee80211_vif_set_links(vlan, add, 0);
+
+		for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
+			link = sdata_dereference(vlan->link[link_id], vlan);
+			ieee80211_link_vlan_copy_chanctx(link);
+		}
+	}
+}
+
+void ieee80211_apvlan_link_setup(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_sub_if_data *ap_bss = container_of(sdata->bss,
+					    struct ieee80211_sub_if_data, u.ap);
+	u16 new_links = ap_bss->vif.valid_links;
+	unsigned long add;
+	int link_id;
+
+	if (!ap_bss->vif.valid_links)
+		return;
+
+	add = new_links;
+	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
+		sdata->wdev.valid_links |= BIT(link_id);
+		ether_addr_copy(sdata->wdev.links[link_id].addr,
+				ap_bss->wdev.links[link_id].addr);
+	}
+
+	ieee80211_vif_set_links(sdata, new_links, 0);
+}
+
+void ieee80211_apvlan_link_clear(struct ieee80211_sub_if_data *sdata)
+{
+	if (!sdata->wdev.valid_links)
+		return;
+
+	sdata->wdev.valid_links = 0;
+	ieee80211_vif_clear_links(sdata);
+}
+
 void ieee80211_link_setup(struct ieee80211_link_data *link)
 {
 	if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
···
 
 	rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf);
 	rcu_assign_pointer(sdata->link[link_id], link);
+
+	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
+		struct ieee80211_sub_if_data *ap_bss;
+		struct ieee80211_bss_conf *ap_bss_conf;
+
+		ap_bss = container_of(sdata->bss,
+				      struct ieee80211_sub_if_data, u.ap);
+		ap_bss_conf = sdata_dereference(ap_bss->vif.link_conf[link_id],
+						ap_bss);
+		memcpy(link_conf, ap_bss_conf, sizeof(*link_conf));
+	}
 
 	link->sdata = sdata;
 	link->link_id = link_id;
···
 	if (!deflink) {
 		switch (sdata->vif.type) {
 		case NL80211_IFTYPE_AP:
+		case NL80211_IFTYPE_AP_VLAN:
 			ether_addr_copy(link_conf->addr,
 					sdata->wdev.links[link_id].addr);
 			link_conf->bssid = link_conf->addr;
···
 
 	switch (sdata->vif.type) {
 	case NL80211_IFTYPE_AP:
+	case NL80211_IFTYPE_AP_VLAN:
 		/* in an AP all links are always active */
 		sdata->vif.active_links = valid_links;
 
···
 		ieee80211_set_vif_links_bitmaps(sdata, new_links, dormant_links);
 
 		/* tell the driver */
-		ret = drv_change_vif_links(sdata->local, sdata,
-					   old_links & old_active,
-					   new_links & sdata->vif.active_links,
-					   old);
+		if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
+			ret = drv_change_vif_links(sdata->local, sdata,
+						   old_links & old_active,
+						   new_links & sdata->vif.active_links,
+						   old);
 		if (!new_links)
 			ieee80211_debugfs_recreate_netdev(sdata, false);
+
+		if (sdata->vif.type == NL80211_IFTYPE_AP)
+			ieee80211_update_apvlan_links(sdata);
 	}
 
 	if (ret) {