interface type switching while up

@@ -370,12 +370,9 @@ static int ieee80211_stop(struct net_dev
 	 * (because if we remove a STA after ops->remove_interface()
 	 * the driver will have removed the vif info already!)
 	 *
-	 * We could relax this and only unlink the stations from the
-	 * hash table and list but keep them on a per-sdata list that
-	 * will be inserted back again when the interface is brought
-	 * up again, but I don't currently see a use case for that,
-	 * except with WDS which gets a STA entry created when it is
-	 * brought up.
+	 * This is relevant only in AP, WDS and mesh modes, since in
+	 * all other modes we've already removed all stations when
+	 * disconnecting etc.
 	 */
 	sta_info_flush(local, sdata);
 

@@ -410,11 +407,21 @@ static int ieee80211_stop(struct net_dev
 		struct ieee80211_sub_if_data *vlan, *tmpsdata;
 		struct beacon_data *old_beacon = sdata->u.ap.beacon;
 
+		/* sdata_running will return false, so this will disable */
+		ieee80211_bss_info_change_notify(sdata,
+						 BSS_CHANGED_BEACON_ENABLED);
+
 		/* remove beacon */
 		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
 		synchronize_rcu();
 		kfree(old_beacon);
 
+		/* free all potentially still buffered bcast frames */
+		while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
+			local->total_ps_buffered--;
+			dev_kfree_skb(skb);
+		}
+
 		/* down all dependent devices, that is VLANs */
 		list_for_each_entry_safe(vlan, tmpsdata, &sdata->u.ap.vlans,
 					 u.vlan.list)

@@ -454,27 +461,6 @@ static int ieee80211_stop(struct net_dev
 
 		ieee80211_configure_filter(local);
 		break;
-	case NL80211_IFTYPE_STATION:
-		del_timer_sync(&sdata->u.mgd.chswitch_timer);
-		del_timer_sync(&sdata->u.mgd.timer);
-		del_timer_sync(&sdata->u.mgd.conn_mon_timer);
-		del_timer_sync(&sdata->u.mgd.bcn_mon_timer);
-		/*
-		 * If any of the timers fired while we waited for it, it will
-		 * have queued its work. Now the work will be running again
-		 * but will not rearm the timer again because it checks
-		 * whether the interface is running, which, at this point,
-		 * it no longer is.
-		 */
-		cancel_work_sync(&sdata->u.mgd.chswitch_work);
-		cancel_work_sync(&sdata->u.mgd.monitor_work);
-		cancel_work_sync(&sdata->u.mgd.beacon_connection_loss_work);
-
-		/* fall through */
-	case NL80211_IFTYPE_ADHOC:
-		if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
-			del_timer_sync(&sdata->u.ibss.timer);
-		/* fall through */
 	case NL80211_IFTYPE_MESH_POINT:
 		if (ieee80211_vif_is_mesh(&sdata->vif)) {
 			/* other_bss and allmulti are always set on mesh

@@ -502,17 +488,19 @@ static int ieee80211_stop(struct net_dev
 			ieee80211_scan_cancel(local);
 
 		/*
-		 * Disable beaconing for AP and mesh, IBSS can't
-		 * still be joined to a network at this point.
+		 * Disable beaconing here for mesh only, AP and IBSS
+		 * are already taken care of.
 		 */
-		if (sdata->vif.type == NL80211_IFTYPE_AP ||
-		    sdata->vif.type == NL80211_IFTYPE_MESH_POINT) {
+		if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
 			ieee80211_bss_info_change_notify(sdata,
 				BSS_CHANGED_BEACON_ENABLED);
-		}
 
-		/* free all remaining keys, there shouldn't be any */
+		/*
+		 * Free all remaining keys, there shouldn't be any,
+		 * except maybe group keys in AP more or WDS?
+		 */
 		ieee80211_free_keys(sdata);
+
 		drv_remove_interface(local, &sdata->vif);
 	}
 

@@ -593,8 +581,6 @@ static void ieee80211_teardown_sdata(str
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_local *local = sdata->local;
-	struct beacon_data *beacon;
-	struct sk_buff *skb;
 	int flushed;
 	int i;
 

@@ -607,37 +593,8 @@ static void ieee80211_teardown_sdata(str
 		__skb_queue_purge(&sdata->fragments[i].skb_list);
 	sdata->fragment_next = 0;
 
-	switch (sdata->vif.type) {
-	case NL80211_IFTYPE_AP:
-		beacon = sdata->u.ap.beacon;
-		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
-		synchronize_rcu();
-		kfree(beacon);
-
-		while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
-			local->total_ps_buffered--;
-			dev_kfree_skb(skb);
-		}
-
-		break;
-	case NL80211_IFTYPE_MESH_POINT:
-		if (ieee80211_vif_is_mesh(&sdata->vif))
-			mesh_rmc_free(sdata);
-		break;
-	case NL80211_IFTYPE_ADHOC:
-		if (WARN_ON(sdata->u.ibss.presp))
-			kfree_skb(sdata->u.ibss.presp);
-		break;
-	case NL80211_IFTYPE_STATION:
-	case NL80211_IFTYPE_WDS:
-	case NL80211_IFTYPE_AP_VLAN:
-	case NL80211_IFTYPE_MONITOR:
-		break;
-	case NL80211_IFTYPE_UNSPECIFIED:
-	case NUM_NL80211_IFTYPES:
-		BUG();
-		break;
-	}
+	if (ieee80211_vif_is_mesh(&sdata->vif))
+		mesh_rmc_free(sdata);
 
 	flushed = sta_info_flush(local, sdata);
 	WARN_ON(flushed);

@@ -991,6 +991,11 @@ static void ieee80211_set_disassoc(struc
 
 	if (remove_sta)
 		sta_info_destroy_addr(sdata, bssid);
+
+	del_timer_sync(&sdata->u.mgd.conn_mon_timer);
+	del_timer_sync(&sdata->u.mgd.bcn_mon_timer);
+	del_timer_sync(&sdata->u.mgd.timer);
+	del_timer_sync(&sdata->u.mgd.chswitch_timer);
 }
 
 void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata,

@@ -81,16 +81,14 @@ static int ieee80211_add_key(struct wiph
 			     u8 key_idx, const u8 *mac_addr,
 			     struct key_params *params)
 {
-	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct sta_info *sta = NULL;
 	struct ieee80211_key *key;
 	int err;
 
-	if (!netif_running(dev))
+	if (!ieee80211_sdata_running(sdata))
 		return -ENETDOWN;
 
-	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-
 	/* reject WEP and TKIP keys if WEP failed to initialize */
 	switch (params->cipher) {
 	case WLAN_CIPHER_SUITE_WEP40:

@@ -339,9 +339,6 @@ static int ieee80211_ifa_changed(struct
 	struct ieee80211_if_managed *ifmgd;
 	int c = 0;
 
-	if (!netif_running(ndev))
-		return NOTIFY_DONE;
-
 	/* Make sure it's our interface that got changed */
 	if (!wdev)
 		return NOTIFY_DONE;

@@ -352,6 +349,9 @@ static int ieee80211_ifa_changed(struct
 	sdata = IEEE80211_DEV_TO_SUB_IF(ndev);
 	bss_conf = &sdata->vif.bss_conf;
 
+	if (!ieee80211_sdata_running(sdata))
+		return NOTIFY_DONE;
+
 	/* ARP filtering is only supported in managed mode */
 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
 		return NOTIFY_DONE;

@@ -1308,7 +1308,7 @@ void ieee80211_recalc_smps(struct ieee80
 	 */
 
 	list_for_each_entry(sdata, &local->interfaces, list) {
-		if (!netif_running(sdata->dev))
+		if (!ieee80211_sdata_running(sdata))
 			continue;
 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
 			goto set;

@@ -103,10 +103,9 @@ static int ieee80211_open(struct net_dev
 	u32 changed = 0;
 	int res;
 	u32 hw_reconf_flags = 0;
-	u8 null_addr[ETH_ALEN] = {0};
 
 	/* fail early if user set an invalid address */
-	if (compare_ether_addr(dev->dev_addr, null_addr) &&
+	if (!is_zero_ether_addr(dev->dev_addr) &&
 	    !is_valid_ether_addr(dev->dev_addr))
 		return -EADDRNOTAVAIL;
 

@@ -195,33 +194,22 @@ static int ieee80211_open(struct net_dev
 	}
 
 	/*
-	 * Check all interfaces and copy the hopefully now-present
-	 * MAC address to those that have the special null one.
+	 * Copy the hopefully now-present MAC address to
+	 * this interface, if it has the special null one.
 	 */
-	list_for_each_entry(nsdata, &local->interfaces, list) {
-		struct net_device *ndev = nsdata->dev;
-
-		/*
-		 * No need to check running since we do not allow
-		 * it to start up with this invalid address.
-		 */
-		if (compare_ether_addr(null_addr, ndev->dev_addr) == 0) {
-			memcpy(ndev->dev_addr,
-			       local->hw.wiphy->perm_addr,
-			       ETH_ALEN);
-			memcpy(ndev->perm_addr, ndev->dev_addr, ETH_ALEN);
+	if (is_zero_ether_addr(dev->dev_addr)) {
+		memcpy(dev->dev_addr,
+		       local->hw.wiphy->perm_addr,
+		       ETH_ALEN);
+		memcpy(dev->perm_addr, dev->dev_addr, ETH_ALEN);
+
+		if (!is_valid_ether_addr(dev->dev_addr)) {
+			if (!local->open_count)
+				drv_stop(local);
+			return -EADDRNOTAVAIL;
 		}
 	}
 
-	/*
-	 * Validate the MAC address for this device.
-	 */
-	if (!is_valid_ether_addr(dev->dev_addr)) {
-		if (!local->open_count)
-			drv_stop(local);
-		return -EADDRNOTAVAIL;
-	}
-
 	switch (sdata->vif.type) {
 	case NL80211_IFTYPE_AP_VLAN:
 		/* no need to tell driver */

@@ -94,20 +94,14 @@ static inline int identical_mac_addr_all
 			 type2 == NL80211_IFTYPE_AP_VLAN));
 }
 
-static int ieee80211_open(struct net_device *dev)
+static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
+					    enum nl80211_iftype iftype)
 {
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-	struct ieee80211_sub_if_data *nsdata;
 	struct ieee80211_local *local = sdata->local;
-	struct sta_info *sta;
-	u32 changed = 0;
-	int res;
-	u32 hw_reconf_flags = 0;
+	struct ieee80211_sub_if_data *nsdata;
+	struct net_device *dev = sdata->dev;
 
-	/* fail early if user set an invalid address */
-	if (!is_zero_ether_addr(dev->dev_addr) &&
-	    !is_valid_ether_addr(dev->dev_addr))
-		return -EADDRNOTAVAIL;
+	ASSERT_RTNL();
 
 	/* we hold the RTNL here so can safely walk the list */
 	list_for_each_entry(nsdata, &local->interfaces, list) {

@@ -124,7 +118,7 @@ static int ieee80211_open(struct net_dev
 			 * belonging to the same hardware. Then, however, we're
 			 * faced with having to adopt two different TSF timers...
 			 */
-			if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
+			if (iftype == NL80211_IFTYPE_ADHOC &&
 			    nsdata->vif.type == NL80211_IFTYPE_ADHOC)
 				return -EBUSY;
 

@@ -138,19 +132,40 @@ static int ieee80211_open(struct net_dev
 			/*
 			 * check whether it may have the same address
 			 */
-			if (!identical_mac_addr_allowed(sdata->vif.type,
+			if (!identical_mac_addr_allowed(iftype,
 							nsdata->vif.type))
 				return -ENOTUNIQ;
 
 			/*
 			 * can only add VLANs to enabled APs
 			 */
-			if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
+			if (iftype == NL80211_IFTYPE_AP_VLAN &&
 			    nsdata->vif.type == NL80211_IFTYPE_AP)
 				sdata->bss = &nsdata->u.ap;
 		}
 	}
 
+	return 0;
+}
+
+static int ieee80211_open(struct net_device *dev)
+{
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	struct ieee80211_local *local = sdata->local;
+	struct sta_info *sta;
+	u32 changed = 0;
+	int res;
+	u32 hw_reconf_flags = 0;
+
+	/* fail early if user set an invalid address */
+	if (!is_zero_ether_addr(dev->dev_addr) &&
+	    !is_valid_ether_addr(dev->dev_addr))
+		return -EADDRNOTAVAIL;
+
+	res = ieee80211_check_concurrent_iface(sdata, sdata->vif.type);
+	if (res)
+		return res;
+
 	switch (sdata->vif.type) {
 	case NL80211_IFTYPE_WDS:
 		if (!is_valid_ether_addr(sdata->u.wds.remote_addr))

@@ -1537,6 +1537,12 @@ enum ieee80211_ampdu_mlme_action {
  *	negative error code (which will be seen in userspace.)
  *	Must be implemented and can sleep.
  *
+ * @change_interface: Called when a netdevice changes type. This callback
+ *	is optional, but only if it is supported can interface types be
+ *	switched while the interface is UP. The callback may sleep.
+ *	Note that while an interface is being switched, it will not be
+ *	found by the interface iteration callbacks.
+ *
  * @remove_interface: Notifies a driver that an interface is going down.
  *	The @stop callback is called after this if it is the last interface
  *	and no monitor interfaces are present.

@@ -1693,6 +1699,9 @@ struct ieee80211_ops {
 	void (*stop)(struct ieee80211_hw *hw);
 	int (*add_interface)(struct ieee80211_hw *hw,
 			     struct ieee80211_vif *vif);
+	int (*change_interface)(struct ieee80211_hw *hw,
+				struct ieee80211_vif *vif,
+				enum nl80211_iftype new_type);
 	void (*remove_interface)(struct ieee80211_hw *hw,
 				 struct ieee80211_vif *vif);
 	int (*config)(struct ieee80211_hw *hw, u32 changed);

245 lines not on this page · raw message

@@ -472,6 +472,16 @@ enum ieee80211_sub_if_data_flags {
 	IEEE80211_SDATA_DONT_BRIDGE_PACKETS	= BIT(3),
 };
 
+/**
+ * enum ieee80211_sdata_state_bits - virtual interface state bits
+ * @SDATA_STATE_RUNNING: virtual interface is up & running; this
+ *	mirrors netif_running() but is separate for interface type
+ *	change handling while the interface is up
+ */
+enum ieee80211_sdata_state_bits {
+	SDATA_STATE_RUNNING,
+};
+
 struct ieee80211_sub_if_data {
 	struct list_head list;
 

@@ -485,6 +495,8 @@ struct ieee80211_sub_if_data {
 
 	unsigned int flags;
 
+	unsigned long state;
+
 	int drop_unencrypted;
 
 	char name[IFNAMSIZ];

@@ -1083,7 +1095,7 @@ void ieee80211_recalc_idle(struct ieee80
 
 static inline bool ieee80211_sdata_running(struct ieee80211_sub_if_data *sdata)
 {
-	return netif_running(sdata->dev);
+	return test_bit(SDATA_STATE_RUNNING, &sdata->state);
 }
 
 /* tx handling */

@@ -52,9 +52,6 @@ static int ieee80211_change_iface(struct
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	int ret;
 
-	if (ieee80211_sdata_running(sdata))
-		return -EBUSY;
-
 	ret = ieee80211_if_change_type(sdata, type);
 	if (ret)
 		return ret;

@@ -54,6 +54,20 @@ static inline int drv_add_interface(stru
 	return ret;
 }
 
+static inline int drv_change_interface(struct ieee80211_local *local,
+				       struct ieee80211_sub_if_data *sdata,
+				       enum nl80211_iftype type)
+{
+	int ret;
+
+	might_sleep();
+
+	trace_drv_change_interface(local, sdata, type);
+	ret = local->ops->change_interface(&local->hw, &sdata->vif, type);
+	trace_drv_return_int(local, ret);
+	return ret;
+}
+
 static inline void drv_remove_interface(struct ieee80211_local *local,
 					struct ieee80211_vif *vif)
 {

@@ -136,6 +136,31 @@ TRACE_EVENT(drv_add_interface,
 	)
 );
 
+TRACE_EVENT(drv_change_interface,
+	TP_PROTO(struct ieee80211_local *local,
+		 struct ieee80211_sub_if_data *sdata,
+		 enum nl80211_iftype type),
+
+	TP_ARGS(local, sdata, type),
+
+	TP_STRUCT__entry(
+		LOCAL_ENTRY
+		VIF_ENTRY
+		__field(u32, new_type)
+	),
+
+	TP_fast_assign(
+		LOCAL_ASSIGN;
+		VIF_ASSIGN;
+		__entry->new_type = type;
+	),
+
+	TP_printk(
+		LOCAL_PR_FMT  VIF_PR_FMT " new type:%d",
+		LOCAL_PR_ARG, VIF_PR_ARG, __entry->new_type
+	)
+);
+
 TRACE_EVENT(drv_remove_interface,
 	TP_PROTO(struct ieee80211_local *local, struct ieee80211_sub_if_data *sdata),
 

@@ -601,6 +601,18 @@ static int mac80211_hwsim_add_interface(
 }
 
 
+static int mac80211_hwsim_change_interface(struct ieee80211_hw *hw,
+					   struct ieee80211_vif *vif,
+					   enum nl80211_iftype newtype)
+{
+	wiphy_debug(hw->wiphy,
+		    "%s (old type=%d, new type=%d, mac_addr=%pM)\n",
+		    __func__, vif->type, newtype, vif->addr);
+	hwsim_check_magic(vif);
+
+	return 0;
+}
+
 static void mac80211_hwsim_remove_interface(
 	struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 {

@@ -1027,6 +1039,7 @@ static struct ieee80211_ops mac80211_hws
 	.start = mac80211_hwsim_start,
 	.stop = mac80211_hwsim_stop,
 	.add_interface = mac80211_hwsim_add_interface,
+	.change_interface = mac80211_hwsim_change_interface,
 	.remove_interface = mac80211_hwsim_remove_interface,
 	.config = mac80211_hwsim_config,
 	.configure_filter = mac80211_hwsim_configure_filter,