nexthop: Use enum to encode notification type

Currently there are only two types of in-kernel nexthop notification.
The two are distinguished by the 'is_grp' boolean field in 'struct
nh_notifier_info'.

As more notification types are introduced for more next-hop group types, a
boolean is not an easily extensible interface. Instead, convert it to an
enum.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 55 insertions, 22 deletions

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index 41424ee909a0..0ac7014703aa 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -4309,11 +4309,18 @@ static int mlxsw_sp_nexthop_obj_validate(struct mlxsw_sp *mlxsw_sp,
 	if (event != NEXTHOP_EVENT_REPLACE)
 		return 0;
 
-	if (!info->is_grp)
+	switch (info->type) {
+	case NH_NOTIFIER_INFO_TYPE_SINGLE:
 		return mlxsw_sp_nexthop_obj_single_validate(mlxsw_sp, info->nh,
 							    info->extack);
-	return mlxsw_sp_nexthop_obj_group_validate(mlxsw_sp, info->nh_grp,
-						   info->extack);
+	case NH_NOTIFIER_INFO_TYPE_GRP:
+		return mlxsw_sp_nexthop_obj_group_validate(mlxsw_sp,
+							   info->nh_grp,
+							   info->extack);
+	default:
+		NL_SET_ERR_MSG_MOD(info->extack, "Unsupported nexthop type");
+		return -EOPNOTSUPP;
+	}
 }
 
 static bool mlxsw_sp_nexthop_obj_is_gateway(struct mlxsw_sp *mlxsw_sp,
@@ -4321,13 +4328,17 @@ static bool mlxsw_sp_nexthop_obj_is_gateway(struct mlxsw_sp *mlxsw_sp,
 {
 	const struct net_device *dev;
 
-	if (info->is_grp)
+	switch (info->type) {
+	case NH_NOTIFIER_INFO_TYPE_SINGLE:
+		dev = info->nh->dev;
+		return info->nh->gw_family || info->nh->is_reject ||
+		       mlxsw_sp_netdev_ipip_type(mlxsw_sp, dev, NULL);
+	case NH_NOTIFIER_INFO_TYPE_GRP:
 		/* Already validated earlier. */
 		return true;
-
-	dev = info->nh->dev;
-	return info->nh->gw_family || info->nh->is_reject ||
-	       mlxsw_sp_netdev_ipip_type(mlxsw_sp, dev, NULL);
+	default:
+		return false;
+	}
 }
 
 static void mlxsw_sp_nexthop_obj_blackhole_init(struct mlxsw_sp *mlxsw_sp,
@@ -4410,11 +4421,22 @@ mlxsw_sp_nexthop_obj_group_info_init(struct mlxsw_sp *mlxsw_sp,
 				     struct mlxsw_sp_nexthop_group *nh_grp,
 				     struct nh_notifier_info *info)
 {
-	unsigned int nhs = info->is_grp ? info->nh_grp->num_nh : 1;
 	struct mlxsw_sp_nexthop_group_info *nhgi;
 	struct mlxsw_sp_nexthop *nh;
+	unsigned int nhs;
 	int err, i;
 
+	switch (info->type) {
+	case NH_NOTIFIER_INFO_TYPE_SINGLE:
+		nhs = 1;
+		break;
+	case NH_NOTIFIER_INFO_TYPE_GRP:
+		nhs = info->nh_grp->num_nh;
+		break;
+	default:
+		return -EINVAL;
+	}
+
 	nhgi = kzalloc(struct_size(nhgi, nexthops, nhs), GFP_KERNEL);
 	if (!nhgi)
 		return -ENOMEM;
@@ -4427,12 +4449,18 @@ mlxsw_sp_nexthop_obj_group_info_init(struct mlxsw_sp *mlxsw_sp,
 		int weight;
 
 		nh = &nhgi->nexthops[i];
-		if (info->is_grp) {
-			nh_obj = &info->nh_grp->nh_entries[i].nh;
-			weight = info->nh_grp->nh_entries[i].weight;
-		} else {
+		switch (info->type) {
+		case NH_NOTIFIER_INFO_TYPE_SINGLE:
 			nh_obj = info->nh;
 			weight = 1;
+			break;
+		case NH_NOTIFIER_INFO_TYPE_GRP:
+			nh_obj = &info->nh_grp->nh_entries[i].nh;
+			weight = info->nh_grp->nh_entries[i].weight;
+			break;
+		default:
+			err = -EINVAL;
+			goto err_nexthop_obj_init;
 		}
 		err = mlxsw_sp_nexthop_obj_init(mlxsw_sp, nh_grp, nh, nh_obj,
 						weight);
diff --git a/drivers/net/netdevsim/fib.c b/drivers/net/netdevsim/fib.c
index 45d8a7790bd5..f140bbca98c5 100644
--- a/drivers/net/netdevsim/fib.c
+++ b/drivers/net/netdevsim/fib.c
@@ -860,7 +860,7 @@ static struct nsim_nexthop *nsim_nexthop_create(struct nsim_fib_data *data,
 
 	nexthop = kzalloc(sizeof(*nexthop), GFP_KERNEL);
 	if (!nexthop)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	nexthop->id = info->id;
 
@@ -868,15 +868,20 @@ static struct nsim_nexthop *nsim_nexthop_create(struct nsim_fib_data *data,
 	 * occupy.
 	 */
 
-	if (!info->is_grp) {
+	switch (info->type) {
+	case NH_NOTIFIER_INFO_TYPE_SINGLE:
 		occ = 1;
-		goto out;
+		break;
+	case NH_NOTIFIER_INFO_TYPE_GRP:
+		for (i = 0; i < info->nh_grp->num_nh; i++)
+			occ += info->nh_grp->nh_entries[i].weight;
+		break;
+	default:
+		NL_SET_ERR_MSG_MOD(info->extack, "Unsupported nexthop type");
+		kfree(nexthop);
+		return ERR_PTR(-EOPNOTSUPP);
 	}
 
-	for (i = 0; i < info->nh_grp->num_nh; i++)
-		occ += info->nh_grp->nh_entries[i].weight;
-
-out:
 	nexthop->occ = occ;
 	return nexthop;
 }
@@ -972,8 +977,8 @@ static int nsim_nexthop_insert(struct nsim_fib_data *data,
 	int err;
 
 	nexthop = nsim_nexthop_create(data, info);
-	if (!nexthop)
-		return -ENOMEM;
+	if (IS_ERR(nexthop))
+		return PTR_ERR(nexthop);
 
 	nexthop_old = rhashtable_lookup_fast(&data->nexthop_ht, &info->id,
 					     nsim_nexthop_ht_params);