gcp: allow users to set podvm disk-type

Currently, the disk type for GCP PodVM creation is hard coded to
pd-standard.

Fixes confidential-containers#2258.

Signed-off-by: Beraldo Leal <bleal@redhat.com>

src/cloud-providers/gcp/manager.go

@@ -24,6 +24,7 @@ func (_ *Manager) ParseCmd(flags *flag.FlagSet) {
 	flags.StringVar(&gcpcfg.ImageId, "imageid", "", "Pod VM image id that is available at GCP Images. Usually a name like 'podvm-image'")
 	flags.StringVar(&gcpcfg.InstanceType, "instance-type", "e2-medium", "Pod VM instance type")
 	flags.StringVar(&gcpcfg.SubnetId, "subnetid", "default", "Network Subnet ID for the VMs")
+	flags.StringVar(&gcpcfg.DiskType, "disk-type", "pd-standard", "Any GCP disk type (pd-standard, pd-ssd, pd-balanced or pd-extreme)")
 }
 
 func (_ *Manager) LoadEnv() {

src/cloud-providers/gcp/provider.go

@@ -107,7 +107,7 @@ func (p *gcpProvider) CreateInstance(ctx context.Context, podName, sandboxID str
 					InitializeParams: &computepb.AttachedDiskInitializeParams{
 						DiskSizeGb:  proto.Int64(20),
 						SourceImage: srcImage,
-						DiskType:    proto.String(fmt.Sprintf("zones/%s/diskTypes/pd-standard", p.serviceConfig.GcpZone)),
+						DiskType:    proto.String(fmt.Sprintf("zones/%s/diskTypes/%s", p.serviceConfig.GcpZone, p.serviceConfig.DiskType)),
 					},
 					AutoDelete: proto.Bool(true),
 					Boot:       proto.Bool(true),

src/cloud-providers/gcp/types.go

@@ -17,6 +17,7 @@ type Config struct {
 	// CAA configuration
 	ImageId        string
 	InstanceType   string
+	DiskType       string
 }
 
 func (c Config) Redact() Config {