Bug 1987845: openstack: relax quota checks in BYON

When deploying OCP with pre-provisioned networks, we do not need to have
available quotas for routers, networks and subnets for the machines
since they are created already.

This patch does the following:

* On Kuryr based deployment:
- Do not touch the quotas on networks / subnets, since we still need to
  have a bunch of quotas to create what's needed for Kuryr.
- Relax the quota on Routers, since it wouldn't create one in BYON mode.

* For other network types:
Relax routers, subnets, networks to be 0 by default and if we don't
configure OCP in BYON mode, then we add the necessary quotas (1 router,
1 network and 1 subnet).

pkg/asset/quota/openstack/openstack.go

@@ -14,9 +14,10 @@ import (
 // These numbers should reflect what is documented here:
 // https://github.com/openshift/installer/tree/master/docs/user/openstack
 // https://github.com/openshift/installer/blob/master/docs/user/openstack/kuryr.md
-// Number or ports here don't include the constraints needed for each machine, which are calculated later
-var networkConstraint = buildNetworkConstraint(15, 1, 1, 1, 3, 60)
-var networkConstraintWithKuryr = buildNetworkConstraint(1500, 1, 250, 250, 250, 1000)
+// Number of ports, routers, subnets and routers here don't include the constraints needed
+// for each machine, which are calculated later
+var minNetworkConstraint = buildNetworkConstraint(15, 0, 0, 0, 3, 60)
+var minNetworkConstraintWithKuryr = buildNetworkConstraint(1500, 1, 250, 250, 250, 1000)
 
 func buildNetworkConstraint(ports, routers, subnets, networks, securityGroups, securityGroupRules int64) []quota.Constraint {
 	return []quota.Constraint{
@@ -31,9 +32,9 @@ func buildNetworkConstraint(ports, routers, subnets, networks, securityGroups, s
 
 func getNetworkConstraints(networkType string) []quota.Constraint {
 	if networkType == string(operv1.NetworkTypeKuryr) {
-		return networkConstraintWithKuryr
+		return minNetworkConstraintWithKuryr
 	}
-	return networkConstraint
+	return minNetworkConstraint
 }
 
 // Constraints returns a list of quota constraints based on the InstallConfig.
@@ -51,9 +52,14 @@ func Constraints(ci *validation.CloudInfo, controlPlanes []machineapi.Machine, c
 		constraints = append(constraints, machineSetConstraints(ci, &computes[i], networkType)...)
 	}
 	constraints = append(constraints, instanceConstraint(int64(len(computes))))
-
-	for _, constraint := range getNetworkConstraints(networkType) {
-		constraints = append(constraints, constraint)
+	constraints = append(constraints, getNetworkConstraints(networkType)...)
+
+	// If the cluster is using pre-provisioned networks, then the quota constraints should be
+	// null because the installer doesn't need to create any resources.
+	if ci.MachinesSubnet == nil {
+		if networkType != string(operv1.NetworkTypeKuryr) {
+			constraints = append(constraints, networkConstraint(1), routerConstraint(1), subnetConstraint(1))
+		}
 	}
 
 	return aggregate(constraints)
@@ -147,6 +153,18 @@ func portConstraint(count int64) quota.Constraint {
 	return generateConstraint("Port", count)
 }
 
+func routerConstraint(count int64) quota.Constraint {
+	return generateConstraint("Router", count)
+}
+
+func networkConstraint(count int64) quota.Constraint {
+	return generateConstraint("Network", count)
+}
+
+func subnetConstraint(count int64) quota.Constraint {
+	return generateConstraint("Subnet", count)
+}
+
 func generateConstraint(name string, count int64) quota.Constraint {
 	return quota.Constraint{
 		Name:  name,