mlxsw: spectrum_buffers: Prevent changing CPU port's configuration

Next patch is going to register the CPU port with devlink, but only so
that the CPU port's shared buffer configuration and occupancy could be
queried.

Prevent changing CPU port's shared buffer threshold and binding
configuration.

Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
index 888ba4300bcc3b5d1888e7d3c87b28d51200e7f7..f1dbde73fa789abff6f35be5291d9d5792448cb9 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
@@ -1085,6 +1085,11 @@ int mlxsw_sp_sb_port_pool_set(struct mlxsw_core_port *mlxsw_core_port,
        u32 max_buff;
        int err;
 
+       if (local_port == MLXSW_PORT_CPU_PORT) {
+               NL_SET_ERR_MSG_MOD(extack, "Changing CPU port's threshold is forbidden");
+               return -EINVAL;
+       }
+
        err = mlxsw_sp_sb_threshold_in(mlxsw_sp, pool_index,
                                       threshold, &max_buff, extack);
        if (err)
@@ -1130,6 +1135,11 @@ int mlxsw_sp_sb_tc_pool_bind_set(struct mlxsw_core_port *mlxsw_core_port,
        u32 max_buff;
        int err;
 
+       if (local_port == MLXSW_PORT_CPU_PORT) {
+               NL_SET_ERR_MSG_MOD(extack, "Changing CPU port's binding is forbidden");
+               return -EINVAL;
+       }
+
        if (dir != mlxsw_sp->sb_vals->pool_dess[pool_index].dir) {
                NL_SET_ERR_MSG_MOD(extack, "Binding egress TC to ingress pool and vice versa is forbidden");
                return -EINVAL;