hypervisor: Add GetTotalMemoryMB to interface

It'll be useful to get the total memory provided to the guest
(hotplugged + coldplugged). We'll use this information when calcualting
how much memory we can add at a time when utilizing ACPI hotplug.

Signed-off-by: Eric Ernst <eric_ernst@apple.com>

src/runtime/virtcontainers/acrn.go

@@ -667,6 +667,10 @@ func (a *Acrn) GetThreadIDs(ctx context.Context) (VcpuThreadIDs, error) {
 	return VcpuThreadIDs{}, nil
 }
 
+func (a *Acrn) GetTotalMemoryMB(ctx context.Context) uint32 {
+	return a.config.MemorySize
+}
+
 func (a *Acrn) ResizeMemory(ctx context.Context, reqMemMB uint32, memoryBlockSizeMB uint32, probe bool) (uint32, MemoryDevice, error) {
 	return 0, MemoryDevice{}, nil
 }

src/runtime/virtcontainers/clh.go

@@ -1576,6 +1576,16 @@ func (clh *cloudHypervisor) cleanupVM(force bool) error {
 	return nil
 }
 
+func (clh *cloudHypervisor) GetTotalMemoryMB(ctx context.Context) uint32 {
+	vminfo, err := clh.vmInfo()
+	if err != nil {
+		clh.Logger().WithError(err).Error("failed to get vminfo")
+		return 0
+	}
+
+	return uint32(vminfo.GetMemoryActualSize() >> utils.MibToBytesShift)
+}
+
 // vmInfo ask to hypervisor for current VM status
 func (clh *cloudHypervisor) vmInfo() (chclient.VmInfo, error) {
 	cl := clh.client()

src/runtime/virtcontainers/fc.go

@@ -1165,6 +1165,10 @@ func (fc *firecracker) HypervisorConfig() HypervisorConfig {
 	return fc.config
 }
 
+func (fc *firecracker) GetTotalMemoryMB(ctx context.Context) uint32 {
+	return fc.config.MemorySize
+}
+
 func (fc *firecracker) ResizeMemory(ctx context.Context, reqMemMB uint32, memoryBlockSizeMB uint32, probe bool) (uint32, MemoryDevice, error) {
 	return 0, MemoryDevice{}, nil
 }

src/runtime/virtcontainers/hypervisor.go

@@ -913,6 +913,7 @@ type Hypervisor interface {
 	HotplugRemoveDevice(ctx context.Context, devInfo interface{}, devType DeviceType) (interface{}, error)
 	ResizeMemory(ctx context.Context, memMB uint32, memoryBlockSizeMB uint32, probe bool) (uint32, MemoryDevice, error)
 	ResizeVCPUs(ctx context.Context, vcpus uint32) (uint32, uint32, error)
+	GetTotalMemoryMB(ctx context.Context) uint32
 	GetVMConsole(ctx context.Context, sandboxID string) (string, string, error)
 	Disconnect(ctx context.Context)
 	Capabilities(ctx context.Context) types.Capabilities

src/runtime/virtcontainers/mock_hypervisor.go

@@ -98,6 +98,9 @@ func (m *mockHypervisor) ResizeVCPUs(ctx context.Context, cpus uint32) (uint32,
 	return 0, 0, nil
 }
 
+func (m *mockHypervisor) GetTotalMemoryMB(ctx context.Context) uint32 {
+	return 0
+}
 func (m *mockHypervisor) Disconnect(ctx context.Context) {
 }
 

src/runtime/virtcontainers/qemu.go

@@ -2159,6 +2159,10 @@ func (q *qemu) Disconnect(ctx context.Context) {
 	q.qmpShutdown()
 }
 
+func (q *qemu) GetTotalMemoryMB(ctx context.Context) uint32 {
+	return q.config.MemorySize + uint32(q.state.HotpluggedMemory)
+}
+
 // ResizeMemory gets a request to update the VM memory to reqMemMB
 // Memory update is managed with two approaches
 // Add memory to VM:
@@ -2172,7 +2176,7 @@ func (q *qemu) Disconnect(ctx context.Context) {
 // A longer term solution is evaluate solutions like virtio-mem
 func (q *qemu) ResizeMemory(ctx context.Context, reqMemMB uint32, memoryBlockSizeMB uint32, probe bool) (uint32, MemoryDevice, error) {
 
-	currentMemory := q.config.MemorySize + uint32(q.state.HotpluggedMemory)
+	currentMemory := q.GetTotalMemoryMB(ctx)
 	if err := q.qmpSetup(); err != nil {
 		return 0, MemoryDevice{}, err
 	}