mlxsw: spectrum_router: Introduce nexthop action field

Currently, the action associated with the nexthop is assumed to be
'forward' unless the 'discard' bit is set.

Instead, simplify this by introducing a dedicated field to represent the
action of the nexthop. This will allow us to more easily introduce more
actions, such as trap.

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

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

@@ -2842,6 +2842,13 @@ enum mlxsw_sp_nexthop_type {
 	MLXSW_SP_NEXTHOP_TYPE_IPIP,
 };
 
+enum mlxsw_sp_nexthop_action {
+	/* Nexthop forwards packets to an egress RIF */
+	MLXSW_SP_NEXTHOP_ACTION_FORWARD,
+	/* Nexthop discards packets */
+	MLXSW_SP_NEXTHOP_ACTION_DISCARD,
+};
+
 struct mlxsw_sp_nexthop_key {
 	struct fib_nh *fib_nh;
 };
@@ -2868,10 +2875,10 @@ struct mlxsw_sp_nexthop {
 	   offloaded:1, /* set indicates this nexthop was written to the
 			 * adjacency table.
 			 */
-	   update:1, /* set indicates this nexthop should be updated in the
+	   update:1; /* set indicates this nexthop should be updated in the
 		      * adjacency table (f.e., its MAC changed).
 		      */
-	   discard:1; /* nexthop is programmed to discard packets */
+	enum mlxsw_sp_nexthop_action action;
 	enum mlxsw_sp_nexthop_type type;
 	union {
 		struct mlxsw_sp_neigh_entry *neigh_entry;
@@ -2981,7 +2988,7 @@ struct mlxsw_sp_nexthop *mlxsw_sp_nexthop_next(struct mlxsw_sp_router *router,
 
 bool mlxsw_sp_nexthop_is_forward(const struct mlxsw_sp_nexthop *nh)
 {
-	return nh->offloaded && !nh->discard;
+	return nh->offloaded && nh->action == MLXSW_SP_NEXTHOP_ACTION_FORWARD;
 }
 
 unsigned char *mlxsw_sp_nexthop_ha(struct mlxsw_sp_nexthop *nh)
@@ -3408,7 +3415,7 @@ static int __mlxsw_sp_nexthop_update(struct mlxsw_sp *mlxsw_sp, u32 adj_index,
 	mlxsw_reg_ratr_pack(ratr_pl, MLXSW_REG_RATR_OP_WRITE_WRITE_ENTRY,
 			    true, MLXSW_REG_RATR_TYPE_ETHERNET,
 			    adj_index, nh->rif->rif_index);
-	if (nh->discard)
+	if (nh->action == MLXSW_SP_NEXTHOP_ACTION_DISCARD)
 		mlxsw_reg_ratr_trap_action_set(ratr_pl,
 					       MLXSW_REG_RATR_TRAP_ACTION_DISCARD_ERRORS);
 	else
@@ -3828,10 +3835,12 @@ mlxsw_sp_nexthop_group_refresh(struct mlxsw_sp *mlxsw_sp,
 static void __mlxsw_sp_nexthop_neigh_update(struct mlxsw_sp_nexthop *nh,
 					    bool removing)
 {
-	if (!removing)
+	if (!removing) {
+		nh->action = MLXSW_SP_NEXTHOP_ACTION_FORWARD;
 		nh->should_offload = 1;
-	else
+	} else {
 		nh->should_offload = 0;
+	}
 	nh->update = 1;
 }
 
@@ -4342,7 +4351,7 @@ static void mlxsw_sp_nexthop_obj_blackhole_init(struct mlxsw_sp *mlxsw_sp,
 {
 	u16 lb_rif_index = mlxsw_sp->router->lb_rif_index;
 
-	nh->discard = 1;
+	nh->action = MLXSW_SP_NEXTHOP_ACTION_DISCARD;
 	nh->should_offload = 1;
 	/* While nexthops that discard packets do not forward packets
 	 * via an egress RIF, they still need to be programmed using a
@@ -4405,7 +4414,7 @@ mlxsw_sp_nexthop_obj_init(struct mlxsw_sp *mlxsw_sp,
 static void mlxsw_sp_nexthop_obj_fini(struct mlxsw_sp *mlxsw_sp,
 				      struct mlxsw_sp_nexthop *nh)
 {
-	if (nh->discard)
+	if (nh->action == MLXSW_SP_NEXTHOP_ACTION_DISCARD)
 		mlxsw_sp_nexthop_obj_blackhole_fini(mlxsw_sp, nh);
 	mlxsw_sp_nexthop_type_fini(mlxsw_sp, nh);
 	list_del(&nh->router_list_node);