1 files changed, 102 insertions, 28 deletions

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 826957b6442b..c18b22c0bf55 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -129,35 +129,52 @@ void dsa_lag_unmap(struct dsa_switch_tree *dst, struct net_device *lag)
 	}
 }
 
+struct dsa_bridge *dsa_tree_bridge_find(struct dsa_switch_tree *dst,
+					const struct net_device *br)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_bridge_dev_get(dp) == br)
+			return dp->bridge;
+
+	return NULL;
+}
+
 static int dsa_bridge_num_find(const struct net_device *bridge_dev)
 {
 	struct dsa_switch_tree *dst;
-	struct dsa_port *dp;
 
-	/* When preparing the offload for a port, it will have a valid
-	 * dp->bridge_dev pointer but a not yet valid dp->bridge_num.
-	 * However there might be other ports having the same dp->bridge_dev
-	 * and a valid dp->bridge_num, so just ignore this port.
-	 */
-	list_for_each_entry(dst, &dsa_tree_list, list)
-		list_for_each_entry(dp, &dst->ports, list)
-			if (dp->bridge_dev == bridge_dev &&
-			    dp->bridge_num != -1)
-				return dp->bridge_num;
+	list_for_each_entry(dst, &dsa_tree_list, list) {
+		struct dsa_bridge *bridge;
+
+		bridge = dsa_tree_bridge_find(dst, bridge_dev);
+		if (bridge)
+			return bridge->num;
+	}
 
-	return -1;
+	return 0;
 }
 
-int dsa_bridge_num_get(const struct net_device *bridge_dev, int max)
+unsigned int dsa_bridge_num_get(const struct net_device *bridge_dev, int max)
 {
-	int bridge_num = dsa_bridge_num_find(bridge_dev);
+	unsigned int bridge_num = dsa_bridge_num_find(bridge_dev);
+
+	/* Switches without FDB isolation support don't get unique
+	 * bridge numbering
+	 */
+	if (!max)
+		return 0;
 
-	if (bridge_num < 0) {
-		/* First port that offloads TX forwarding for this bridge */
-		bridge_num = find_first_zero_bit(&dsa_fwd_offloading_bridges,
-						 DSA_MAX_NUM_OFFLOADING_BRIDGES);
+	if (!bridge_num) {
+		/* First port that requests FDB isolation or TX forwarding
+		 * offload for this bridge
+		 */
+		bridge_num = find_next_zero_bit(&dsa_fwd_offloading_bridges,
+						DSA_MAX_NUM_OFFLOADING_BRIDGES,
+						1);
 		if (bridge_num >= max)
-			return -1;
+			return 0;
 
 		set_bit(bridge_num, &dsa_fwd_offloading_bridges);
 	}
@@ -165,13 +182,14 @@ int dsa_bridge_num_get(const struct net_device *bridge_dev, int max)
 	return bridge_num;
 }
 
-void dsa_bridge_num_put(const struct net_device *bridge_dev, int bridge_num)
+void dsa_bridge_num_put(const struct net_device *bridge_dev,
+			unsigned int bridge_num)
 {
-	/* Check if the bridge is still in use, otherwise it is time
-	 * to clean it up so we can reuse this bridge_num later.
+	/* Since we refcount bridges, we know that when we call this function
+	 * it is no longer in use, so we can just go ahead and remove it from
+	 * the bit mask.
 	 */
-	if (dsa_bridge_num_find(bridge_dev) < 0)
-		clear_bit(bridge_num, &dsa_fwd_offloading_bridges);
+	clear_bit(bridge_num, &dsa_fwd_offloading_bridges);
 }
 
 struct dsa_switch *dsa_switch_find(int tree_index, int sw_index)
@@ -804,7 +822,7 @@ static int dsa_switch_setup_tag_protocol(struct dsa_switch *ds)
 	int err;
 
 	if (tag_ops->proto == dst->default_proto)
-		return 0;
+		goto connect;
 
 	dsa_switch_for_each_cpu_port(cpu_dp, ds) {
 		rtnl_lock();
@@ -818,7 +836,30 @@ static int dsa_switch_setup_tag_protocol(struct dsa_switch *ds)
 		}
 	}
 
+connect:
+	if (tag_ops->connect) {
+		err = tag_ops->connect(ds);
+		if (err)
+			return err;
+	}
+
+	if (ds->ops->connect_tag_protocol) {
+		err = ds->ops->connect_tag_protocol(ds, tag_ops->proto);
+		if (err) {
+			dev_err(ds->dev,
+				"Unable to connect to tag protocol \"%s\": %pe\n",
+				tag_ops->name, ERR_PTR(err));
+			goto disconnect;
+		}
+	}
+
 	return 0;
+
+disconnect:
+	if (tag_ops->disconnect)
+		tag_ops->disconnect(ds);
+
+	return err;
 }
 
 static int dsa_switch_setup(struct dsa_switch *ds)
@@ -1118,6 +1159,37 @@ static void dsa_tree_teardown(struct dsa_switch_tree *dst)
 	dst->setup = false;
 }
 
+static int dsa_tree_bind_tag_proto(struct dsa_switch_tree *dst,
+				   const struct dsa_device_ops *tag_ops)
+{
+	const struct dsa_device_ops *old_tag_ops = dst->tag_ops;
+	struct dsa_notifier_tag_proto_info info;
+	int err;
+
+	dst->tag_ops = tag_ops;
+
+	/* Notify the switches from this tree about the connection
+	 * to the new tagger
+	 */
+	info.tag_ops = tag_ops;
+	err = dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO_CONNECT, &info);
+	if (err && err != -EOPNOTSUPP)
+		goto out_disconnect;
+
+	/* Notify the old tagger about the disconnection from this tree */
+	info.tag_ops = old_tag_ops;
+	dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO_DISCONNECT, &info);
+
+	return 0;
+
+out_disconnect:
+	info.tag_ops = tag_ops;
+	dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO_DISCONNECT, &info);
+	dst->tag_ops = old_tag_ops;
+
+	return err;
+}
+
 /* Since the dsa/tagging sysfs device attribute is per master, the assumption
  * is that all DSA switches within a tree share the same tagger, otherwise
  * they would have formed disjoint trees (different "dsa,member" values).
@@ -1150,12 +1222,15 @@ int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst,
 			goto out_unlock;
 	}
 
+	/* Notify the tag protocol change */
 	info.tag_ops = tag_ops;
 	err = dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO, &info);
 	if (err)
-		goto out_unwind_tagger;
+		return err;
 
-	dst->tag_ops = tag_ops;
+	err = dsa_tree_bind_tag_proto(dst, tag_ops);
+	if (err)
+		goto out_unwind_tagger;
 
 	rtnl_unlock();
 
@@ -1184,7 +1259,6 @@ static struct dsa_port *dsa_port_touch(struct dsa_switch *ds, int index)
 
 	dp->ds = ds;
 	dp->index = index;
-	dp->bridge_num = -1;
 
 	INIT_LIST_HEAD(&dp->list);
 	list_add_tail(&dp->list, &dst->ports);