net: bridge: Introduce UAPI for BR_BOOLOPT_FDB_LOCAL_VLAN_0

The previous patches introduced a new option, BR_BOOLOPT_FDB_LOCAL_VLAN_0.
When enabled, it has local FDB entries installed only on VLAN 0, instead of
duplicating them across all VLANs.

In this patch, add the corresponding UAPI toggle, and the code for turning
the feature on and off.

Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/ea99bfb10f687fa58091e6e1c2f8acc33f47ca45.1757004393.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 96 insertions, 0 deletions

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 4a20578517a5..58d22e2b85fc 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -582,6 +582,102 @@ void br_fdb_cleanup(struct work_struct *work)
 	mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
 }
 
+static void br_fdb_delete_locals_per_vlan_port(struct net_bridge *br,
+					       struct net_bridge_port *p)
+{
+	struct net_bridge_vlan_group *vg;
+	struct net_bridge_vlan *v;
+	struct net_device *dev;
+
+	if (p) {
+		vg = nbp_vlan_group(p);
+		dev = p->dev;
+	} else {
+		vg = br_vlan_group(br);
+		dev = br->dev;
+	}
+
+	list_for_each_entry(v, &vg->vlan_list, vlist)
+		br_fdb_find_delete_local(br, p, dev->dev_addr, v->vid);
+}
+
+static void br_fdb_delete_locals_per_vlan(struct net_bridge *br)
+{
+	struct net_bridge_port *p;
+
+	ASSERT_RTNL();
+
+	list_for_each_entry(p, &br->port_list, list)
+		br_fdb_delete_locals_per_vlan_port(br, p);
+
+	br_fdb_delete_locals_per_vlan_port(br, NULL);
+}
+
+static int br_fdb_insert_locals_per_vlan_port(struct net_bridge *br,
+					      struct net_bridge_port *p,
+					      struct netlink_ext_ack *extack)
+{
+	struct net_bridge_vlan_group *vg;
+	struct net_bridge_vlan *v;
+	struct net_device *dev;
+	int err;
+
+	if (p) {
+		vg = nbp_vlan_group(p);
+		dev = p->dev;
+	} else {
+		vg = br_vlan_group(br);
+		dev = br->dev;
+	}
+
+	list_for_each_entry(v, &vg->vlan_list, vlist) {
+		if (!br_vlan_should_use(v))
+			continue;
+
+		err = br_fdb_add_local(br, p, dev->dev_addr, v->vid);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int br_fdb_insert_locals_per_vlan(struct net_bridge *br,
+					 struct netlink_ext_ack *extack)
+{
+	struct net_bridge_port *p;
+	int err;
+
+	ASSERT_RTNL();
+
+	list_for_each_entry(p, &br->port_list, list) {
+		err = br_fdb_insert_locals_per_vlan_port(br, p, extack);
+		if (err)
+			goto rollback;
+	}
+
+	err = br_fdb_insert_locals_per_vlan_port(br, NULL, extack);
+	if (err)
+		goto rollback;
+
+	return 0;
+
+rollback:
+	NL_SET_ERR_MSG_MOD(extack, "fdb_local_vlan_0 toggle: FDB entry insertion failed");
+	br_fdb_delete_locals_per_vlan(br);
+	return err;
+}
+
+int br_fdb_toggle_local_vlan_0(struct net_bridge *br, bool on,
+			       struct netlink_ext_ack *extack)
+{
+	if (!on)
+		return br_fdb_insert_locals_per_vlan(br, extack);
+
+	br_fdb_delete_locals_per_vlan(br);
+	return 0;
+}
+
 static bool __fdb_flush_matches(const struct net_bridge *br,
 				const struct net_bridge_fdb_entry *f,
 				const struct net_bridge_fdb_flush_desc *desc)