libvirt: Add podvm instance cpu and mem size support for libvirt

src/cloud-api-adaptor/entrypoint.sh

@@ -152,13 +152,17 @@ libvirt() {
     test_vars LIBVIRT_URI
 
     [[ "${DISABLECVM}" = "true" ]] && optionals+="-disable-cvm "
+    [[ "${LIBVIRT_CPU}" ]] && optionals+="-CPU ${LIBVIRT_CPU} "
+    [[ "${LIBVIRT_MEMORY}" ]] && optionals+="-Memory ${LIBVIRT_MEMORY} "
+
     set -x
     exec cloud-api-adaptor libvirt \
         -uri "${LIBVIRT_URI}" \
         -data-dir /opt/data-dir \
         -pods-dir /run/peerpod/pods \
         -network-name "${LIBVIRT_NET:-default}" \
         -pool-name "${LIBVIRT_POOL:-default}" \
+
         ${optionals} \
         -socket /run/peerpod/hypervisor.sock
 }

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

@@ -28,6 +28,8 @@ configMapGenerator:
   - LIBVIRT_EFI_FIRMWARE="/usr/share/OVMF/OVMF_CODE_4M.fd" # Edit to change the EFI firmware path, or comment to unset, if not using EFI.
   #- LIBVIRT_LAUNCH_SECURITY="" #sev or s390-pv
   #- LIBVIRT_VOL_NAME="" # Uncomment and set if you want to use a specific volume name. Defaults to podvm-base.qcow2
+  #- LIBVIRT_CPU="2"
+  #- LIBVIRT_Memory="800
   #- 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

src/cloud-providers/libvirt/libvirt.go

@@ -29,12 +29,6 @@ const (
 	GetDomainIPsRetries = 20
 	// The sleep time between retries to get the domain IP addresses
 	GetDomainIPsSleep = time.Second * 3
-	// Default Memory size
-	LIBVIRT_DEF_MEM_SIZE = uint(8)
-	// Default CPU size
-	LIBVIRT_DEF_CPU_SIZE = uint(2)
-	// Convert Memory size from MegaBytes to GigaBytes
-	LIBVIRT_CONV_MEM = 1000
 )
 
 type domainConfig struct {
@@ -666,14 +660,6 @@ func getDomainIPs(dom *libvirt.Domain) ([]netip.Addr, error) {
 
 func CreateDomain(ctx context.Context, libvirtClient *libvirtClient, v *vmConfig) (result *createDomainOutput, err error) {
 
-	// Assign the default CPU size and memory when no default memory and
-	// CPU are provided through annotations
-	if v.cpu == 0 {
-		v.cpu = LIBVIRT_DEF_CPU_SIZE
-	}
-	if v.mem == 0 {
-		v.mem = LIBVIRT_DEF_MEM_SIZE
-	}
 	v.rootDiskSize = uint64(10)
 
 	exists, err := checkDomainExistsByName(v.name, libvirtClient)

src/cloud-providers/libvirt/manager.go

@@ -7,6 +7,7 @@ package libvirt
 
 import (
 	"flag"
+	"strconv"
 
 	provider "github.com/confidential-containers/cloud-api-adaptor/src/cloud-providers"
 )
@@ -23,6 +24,8 @@ const (
 	defaultVolName        = "podvm-base.qcow2"
 	defaultLaunchSecurity = ""
 	defaultFirmware       = ""
+	defaultCPU            = "2"
+	defaultMemory         = "8000"
 )
 
 func init() {
@@ -38,7 +41,8 @@ func (_ *Manager) ParseCmd(flags *flag.FlagSet) {
 	flags.BoolVar(&libvirtcfg.DisableCVM, "disable-cvm", false, "Use non-CVMs for peer pods")
 	flags.StringVar(&libvirtcfg.LaunchSecurity, "launch-security", defaultLaunchSecurity, "Libvirt's LaunchSecurity element for Confidential VMs. SEV or s390-pv. If omitted, will automatically determine.")
 	flags.StringVar(&libvirtcfg.Firmware, "firmware", defaultFirmware, "Path to OVMF")
-
+	flags.UintVar(&libvirtcfg.CPU, "CPU", 2, "Number of processors allocated")
+	flags.UintVar(&libvirtcfg.Memory, "Memory", 8, "Amount of memory in GB")
 }
 
 func (_ *Manager) LoadEnv() {
@@ -48,6 +52,20 @@ func (_ *Manager) LoadEnv() {
 	provider.DefaultToEnv(&libvirtcfg.VolName, "LIBVIRT_VOL_NAME", defaultVolName)
 	provider.DefaultToEnv(&libvirtcfg.LaunchSecurity, "LIBVIRT_LAUNCH_SECURITY", defaultLaunchSecurity)
 	provider.DefaultToEnv(&libvirtcfg.Firmware, "LIBVIRT_EFI_FIRMWARE", defaultFirmware)
+
+	var memoryStr, processorsStr string
+	provider.DefaultToEnv(&memoryStr, "LIBVIRT_MEMORY", defaultMemory)
+	if memoryStr != "" {
+		memory, _ := strconv.ParseUint(memoryStr, 10, 64)
+		libvirtcfg.Memory = uint(memory)
+	}
+
+	provider.DefaultToEnv(&processorsStr, "LIBVIRT_CPU", defaultCPU)
+	if processorsStr != "" {
+		cpu, _ := strconv.ParseUint(processorsStr, 10, 64)
+		libvirtcfg.CPU = uint(cpu)
+	}
+
 }
 
 func (_ *Manager) NewProvider() (provider.Provider, error) {

src/cloud-providers/libvirt/provider.go

@@ -20,6 +20,9 @@
 
 const maxInstanceNameLen = 63
 
+// Convert Memory size from MegaBytes to GigaBytes
+LIBVIRT_CONV_MEM  = 1000
+
 type libvirtProvider struct {
 	libvirtClient *libvirtClient
 	serviceConfig *Config
@@ -57,8 +60,15 @@
 	}
 
 	// Convert the memory units in gigabytes
 	instanceMemory := uint(spec.Memory / LIBVIRT_CONV_MEM)
+	if instanceMemory == 0 {
+		instanceMemory =  uint(p.serviceConfig.Memory / LIBVIRT_CONV_MEM)
+	}	
+
 	instanceVCPUs := uint(spec.VCPUs)
+	if instanceVCPUs == 0 {
+		instanceVCPUs = uint(p.serviceConfig.CPU)
+	}	
 
 	// TODO: Specify the maximum instance name length in Libvirt
 	vm := &vmConfig{name: instanceName, cpu: instanceVCPUs, mem: instanceMemory, userData: userData, firmware: p.serviceConfig.Firmware}

src/cloud-providers/libvirt/types.go

@@ -21,6 +21,8 @@ type Config struct {
 	VolName        string
 	LaunchSecurity string
 	Firmware       string
+	CPU            uint
+	Memory         uint
 }
 
 type vmConfig struct {