mlxsw: spectrum_router: Add an indication if a nexthop group can be destroyed

Currently, a nexthop group is destroyed when the last FIB entry is
detached from it.

When nexthop objects are supported, this can no longer be the case, as
the group is a separate object whose lifetime is managed by user space.

Add an indication if a nexthop group can be destroyed and always set it
to true for the existing IPv4 and IPv6 nexthop groups.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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

@@ -2897,6 +2897,7 @@ struct mlxsw_sp_nexthop_group {
 	};
 	struct mlxsw_sp_nexthop_group_info *nhgi;
 	enum mlxsw_sp_nexthop_group_type type;
+	bool can_destroy;
 };
 
 void mlxsw_sp_nexthop_counter_alloc(struct mlxsw_sp *mlxsw_sp,
@@ -4173,6 +4174,8 @@ mlxsw_sp_nexthop4_group_create(struct mlxsw_sp *mlxsw_sp, struct fib_info *fi)
 	if (err)
 		goto err_nexthop_group_insert;
 
+	nh_grp->can_destroy = true;
+
 	return nh_grp;
 
 err_nexthop_group_insert:
@@ -4187,6 +4190,8 @@ static void
 mlxsw_sp_nexthop4_group_destroy(struct mlxsw_sp *mlxsw_sp,
 				struct mlxsw_sp_nexthop_group *nh_grp)
 {
+	if (!nh_grp->can_destroy)
+		return;
 	mlxsw_sp_nexthop_group_remove(mlxsw_sp, nh_grp);
 	mlxsw_sp_nexthop4_group_info_fini(mlxsw_sp, nh_grp);
 	fib_info_put(nh_grp->ipv4.fi);
@@ -5479,6 +5484,8 @@ mlxsw_sp_nexthop6_group_create(struct mlxsw_sp *mlxsw_sp,
 	if (err)
 		goto err_nexthop_group_insert;
 
+	nh_grp->can_destroy = true;
+
 	return nh_grp;
 
 err_nexthop_group_insert:
@@ -5492,6 +5499,8 @@ static void
 mlxsw_sp_nexthop6_group_destroy(struct mlxsw_sp *mlxsw_sp,
 				struct mlxsw_sp_nexthop_group *nh_grp)
 {
+	if (!nh_grp->can_destroy)
+		return;
 	mlxsw_sp_nexthop_group_remove(mlxsw_sp, nh_grp);
 	mlxsw_sp_nexthop6_group_info_fini(mlxsw_sp, nh_grp);
 	kfree(nh_grp);