mlxsw: spectrum_nve: Add API to resolve learned IP addresses

FDB notifications for entries learned from an NVE tunnel contain the IP
address of the remote VTEP. In the case of IPv4 underlay, the IP address
is specified as-is. IPv6 addresses on the other hand, are specified as
handles which then need to be used to query the actual address from the
device.

Only IPv4 underlay is currently supported, so we cannot receive
notifications for IPv6 addresses and therefore an error is returned when
one tries to resolve such an address.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

@@ -813,6 +813,9 @@ struct mlxsw_sp_nve_params {
 extern const struct mlxsw_sp_nve_ops *mlxsw_sp1_nve_ops_arr[];
 extern const struct mlxsw_sp_nve_ops *mlxsw_sp2_nve_ops_arr[];
 
+int mlxsw_sp_nve_learned_ip_resolve(struct mlxsw_sp *mlxsw_sp, u32 uip,
+				    enum mlxsw_sp_l3proto proto,
+				    union mlxsw_sp_l3addr *addr);
 int mlxsw_sp_nve_flood_ip_add(struct mlxsw_sp *mlxsw_sp,
 			      struct mlxsw_sp_fid *fid,
 			      enum mlxsw_sp_l3proto proto,

drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c

@@ -174,6 +174,20 @@ mlxsw_sp_nve_mc_record_ops_arr[] = {
 	[MLXSW_SP_L3_PROTO_IPV6] = &mlxsw_sp_nve_mc_record_ipv6_ops,
 };
 
+int mlxsw_sp_nve_learned_ip_resolve(struct mlxsw_sp *mlxsw_sp, u32 uip,
+				    enum mlxsw_sp_l3proto proto,
+				    union mlxsw_sp_l3addr *addr)
+{
+	switch (proto) {
+	case MLXSW_SP_L3_PROTO_IPV4:
+		addr->addr4 = cpu_to_be32(uip);
+		return 0;
+	default:
+		WARN_ON(1);
+		return -EINVAL;
+	}
+}
+
 static struct mlxsw_sp_nve_mc_list *
 mlxsw_sp_nve_mc_list_find(struct mlxsw_sp *mlxsw_sp,
 			  const struct mlxsw_sp_nve_mc_list_key *key)