3 files changed, 62 insertions, 18 deletions
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index fe971a2c15cd..89c6c86e746f 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -507,6 +507,66 @@ int dsa_port_walk_mdbs(struct dsa_switch *ds, int port, dsa_fdb_walk_cb_t cb)
 }
 EXPORT_SYMBOL_GPL(dsa_port_walk_mdbs);
 
+bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b)
+{
+	if (a->type != b->type)
+		return false;
+
+	switch (a->type) {
+	case DSA_DB_PORT:
+		return a->dp == b->dp;
+	case DSA_DB_LAG:
+		return a->lag.dev == b->lag.dev;
+	case DSA_DB_BRIDGE:
+		return a->bridge.num == b->bridge.num;
+	default:
+		WARN_ON(1);
+		return false;
+	}
+}
+
+bool dsa_fdb_present_in_other_db(struct dsa_switch *ds, int port,
+				 const unsigned char *addr, u16 vid,
+				 struct dsa_db db)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	struct dsa_mac_addr *a;
+
+	lockdep_assert_held(&dp->addr_lists_lock);
+
+	list_for_each_entry(a, &dp->fdbs, list) {
+		if (!ether_addr_equal(a->addr, addr) || a->vid != vid)
+			continue;
+
+		if (a->db.type == db.type && !dsa_db_equal(&a->db, &db))
+			return true;
+	}
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(dsa_fdb_present_in_other_db);
+
+bool dsa_mdb_present_in_other_db(struct dsa_switch *ds, int port,
+				 const struct switchdev_obj_port_mdb *mdb,
+				 struct dsa_db db)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	struct dsa_mac_addr *a;
+
+	lockdep_assert_held(&dp->addr_lists_lock);
+
+	list_for_each_entry(a, &dp->mdbs, list) {
+		if (!ether_addr_equal(a->addr, mdb->addr) || a->vid != mdb->vid)
+			continue;
+
+		if (a->db.type == db.type && !dsa_db_equal(&a->db, &db))
+			return true;
+	}
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(dsa_mdb_present_in_other_db);
+
 static int __init dsa_init_module(void)
 {
 	int rc;
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index c3c7491ace72..f20bdd8ea0a8 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -182,6 +182,8 @@ const struct dsa_device_ops *dsa_tag_driver_get(int tag_protocol);
 void dsa_tag_driver_put(const struct dsa_device_ops *ops);
 const struct dsa_device_ops *dsa_find_tagger_by_name(const char *buf);
 
+bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b);
+
 bool dsa_schedule_work(struct work_struct *work);
 const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops);
 
diff --git a/net/dsa/switch.c b/net/dsa/switch.c
index 327d66bf7b47..d25cd1da3eb3 100644
--- a/net/dsa/switch.c
+++ b/net/dsa/switch.c
@@ -212,24 +212,6 @@ static bool dsa_port_host_address_match(struct dsa_port *dp,
 	return false;
 }
 
-static bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b)
-{
-	if (a->type != b->type)
-		return false;
-
-	switch (a->type) {
-	case DSA_DB_PORT:
-		return a->dp == b->dp;
-	case DSA_DB_LAG:
-		return a->lag.dev == b->lag.dev;
-	case DSA_DB_BRIDGE:
-		return a->bridge.num == b->bridge.num;
-	default:
-		WARN_ON(1);
-		return false;
-	}
-}
-
 static struct dsa_mac_addr *dsa_mac_addr_find(struct list_head *addr_list,
 					      const unsigned char *addr, u16 vid,
 					      struct dsa_db db)