gcp: fetch disk image size dynamically

Remove the hardcoded disk size and retrieve it from the API instead.

Signed-off-by: Beraldo Leal <[email protected]>

Author: beraldoleal

src/cloud-api-adaptor/entrypoint.sh

@@ -96,10 +96,11 @@ gcp() {
 
     [[ "${PODVM_IMAGE_NAME}" ]] && optionals+="-image-name ${PODVM_IMAGE_NAME} "
     [[ "${GCP_PROJECT_ID}" ]] && optionals+="-gcp-project-id ${GCP_PROJECT_ID} "
-    [[ "${GCP_ZONE}" ]] && optionals+="-zone ${GCP_ZONE} "                         # if not set retrieved from IMDS
-    [[ "${GCP_MACHINE_TYPE}" ]] && optionals+="-machine-type ${GCP_MACHINE_TYPE} "     # default e2-medium
-    [[ "${GCP_NETWORK}" ]] && optionals+="-network ${GCP_NETWORK} "                # defaults to 'default'
-    [[ "${GCP_DISK_TYPE}" ]] && optionals+="-disk-type ${GCP_DISK_TYPE} "              # defaults to 'pd-standard'
+    [[ "${GCP_ZONE}" ]] && optionals+="-zone ${GCP_ZONE} "                                         # if not set retrieved from IMDS
+    [[ "${GCP_MACHINE_TYPE}" ]] && optionals+="-machine-type ${GCP_MACHINE_TYPE} "                 # default e2-medium
+    [[ "${GCP_NETWORK}" ]] && optionals+="-network ${GCP_NETWORK} "                                # defaults to 'default'
+    [[ "${GCP_DISK_TYPE}" ]] && optionals+="-disk-type ${GCP_DISK_TYPE} "                          # defaults to 'pd-standard'
+    [[ "${ROOT_VOLUME_SIZE}" ]] && optionals+="-root-volume-size ${ROOT_VOLUME_SIZE} "             # Specify root volume size for pod vm
 
     set -x
 

src/cloud-api-adaptor/install/overlays/gcp/kustomization.yaml

@@ -17,14 +17,18 @@ configMapGenerator:
   namespace: confidential-containers-system
   literals:
   - CLOUD_PROVIDER="gcp"
-  #- PAUSE_IMAGE="" # Uncomment and set if you want to use a specific pause image
-  #- TUNNEL_TYPE="" # Uncomment and set if you want to use a specific tunnel type. Defaults to vxlan
-  #- VXLAN_PORT="" # Uncomment and set if you want to use a specific vxlan port. Defaults to 4789
   - PODVM_IMAGE_NAME="" # set from step "Build Pod VM Image" in gcp/README.md
   - GCP_PROJECT_ID="" # set
   - GCP_ZONE="" # set e.g. "us-west1-a"
   - GCP_MACHINE_TYPE="e2-medium" # replace if needed. caa defaults to e2-medium
   - GCP_NETWORK="global/networks/default" # replace if needed.
+  #- PEERPODS_LIMIT_PER_NODE="10" # Max number of peer pods that can be created per node. Default is 10
+  #- REMOTE_HYPERVISOR_ENDPOINT="/run/peerpod/hypervisor.sock" # Path to Kata remote hypervisor socket. Default is /run/peerpod/hypervisor.sock
+  #- PEER_PODS_DIR="/run/peerpod/pods" # Path to peer pods directory. Default is /run/peerpod/pods
+  #- PAUSE_IMAGE="" # Uncomment and set if you want to use a specific pause image
+  #- ROOT_VOLUME_SIZE="10" # Uncomment and set if you want to use a specific root volume size. Defaults to 10
+  #- TUNNEL_TYPE="" # Uncomment and set if you want to use a specific tunnel type. Defaults to vxlan
+  #- VXLAN_PORT="" # Uncomment and set if you want to use a specific vxlan port. Defaults to 4789
 ##TLS_SETTINGS
   #- CACERT_FILE="/etc/certificates/ca.crt" # for TLS
   #- CERT_FILE="/etc/certificates/client.crt" # for TLS

src/cloud-providers/gcp/manager.go

@@ -26,6 +26,7 @@ func (_ *Manager) ParseCmd(flags *flag.FlagSet) {
 	flags.StringVar(&gcpcfg.MachineType, "machine-type", "e2-medium", "Pod VM instance type")
 	flags.StringVar(&gcpcfg.Network, "network", "", "Network ID to be used for the Pod VMs")
 	flags.StringVar(&gcpcfg.DiskType, "disk-type", "pd-standard", "Any GCP disk type (pd-standard, pd-ssd, pd-balanced or pd-extreme)")
+	flags.IntVar(&gcpcfg.RootVolumeSize, "root-volume-size", 10, "Root volume size (in GiB) for the Pod VMs")
 }
 
 func (_ *Manager) LoadEnv() {

src/cloud-providers/gcp/provider.go

@@ -76,6 +76,29 @@ func getIPs(instance *computepb.Instance) ([]netip.Addr, error) {
 	return podNodeIPs, nil
 }
 
+func (p *gcpProvider) getImageSizeGB(ctx context.Context, image string) (int64, error) {
+	client, err := compute.NewImagesRESTClient(ctx)
+	if err != nil {
+		return 0, fmt.Errorf("failed to create compute client: %w", err)
+	}
+	defer client.Close()
+
+	parts := strings.Split(image, "/")
+	imageName := parts[len(parts)-1]
+
+	req := &computepb.GetImageRequest{
+		Project: p.serviceConfig.ProjectId,
+		Image:   imageName,
+	}
+
+	img, err := client.Get(ctx, req)
+	if err != nil {
+		return 0, fmt.Errorf("Failed to get image for %s: %w", image, err)
+	}
+
+	return img.GetDiskSizeGb(), nil
+}
+
 func (p *gcpProvider) CreateInstance(ctx context.Context, podName, sandboxID string, cloudConfig cloudinit.CloudConfigGenerator, spec provider.InstanceTypeSpec) (*provider.Instance, error) {
 
 	instanceName := util.GenerateInstanceName(podName, sandboxID, maxInstanceNameLen)
@@ -105,6 +128,16 @@ func (p *gcpProvider) CreateInstance(ctx context.Context, podName, sandboxID str
 		srcImage = proto.String(spec.Image)
 	}
 
+	imageSizeGB, err := p.getImageSizeGB(ctx, *srcImage)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to get image size: %w", err)
+	}
+
+	// If user provided RootVolumeSize, use the larger of the two
+	if p.serviceConfig.RootVolumeSize > 0 && int64(p.serviceConfig.RootVolumeSize) > imageSizeGB {
+		imageSizeGB = int64(p.serviceConfig.RootVolumeSize)
+	}
+
 	insertReq := &computepb.InsertInstanceRequest{
 		Project: p.serviceConfig.ProjectId,
 		Zone:    p.serviceConfig.Zone,
@@ -113,7 +146,7 @@ func (p *gcpProvider) CreateInstance(ctx context.Context, podName, sandboxID str
 			Disks: []*computepb.AttachedDisk{
 				{
 					InitializeParams: &computepb.AttachedDiskInitializeParams{
-						DiskSizeGb:  proto.Int64(20),
+						DiskSizeGb:  proto.Int64(imageSizeGB),
 						SourceImage: srcImage,
 						DiskType:    proto.String(fmt.Sprintf("zones/%s/diskTypes/%s", p.serviceConfig.Zone, p.serviceConfig.DiskType)),
 					},

src/cloud-providers/gcp/types.go

@@ -8,13 +8,14 @@ import (
 )
 
 type Config struct {
-	GcpCredentials string
-	ProjectId      string
-	Zone           string
-	ImageName      string
-	MachineType    string
-	Network        string
-	DiskType       string
+	GcpCredentials   string
+	ProjectId        string
+	Zone             string
+	ImageName        string
+	MachineType      string
+	Network          string
+	DiskType         string
+	RootVolumeSize   int
 }
 
 func (c Config) Redact() Config {