From 6aff077901021d9a0075c446dfe281b2487e1487 Mon Sep 17 00:00:00 2001
From: Liam Merwick <liam.merwick@oracle.com>
Date: Fri, 24 Apr 2020 12:14:10 +0000
Subject: [PATCH] virtcontainers: x86: Support microvm machine type

With the addition of support to govmm for multiple transports (intel/govmm#111)
and microvm (intel/govmm#121) we can now enable support for the 'microvm'
machine type in kata-runtime.

Fixes: #2360

Signed-off-by: Liam Merwick <liam.merwick@oracle.com>
---
 pkg/katautils/config.go           |  9 +++++++++
 virtcontainers/qemu_amd64.go      | 17 ++++++++++++++---
 virtcontainers/qemu_amd64_test.go | 23 +++++++++++++++++++++++
 virtcontainers/qemu_arch_base.go  |  3 +++
 4 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/pkg/katautils/config.go b/pkg/katautils/config.go
index 14794a24ff..d4a4ee3111 100644
--- a/pkg/katautils/config.go
+++ b/pkg/katautils/config.go
@@ -14,6 +14,7 @@ import (
 	"strings"
 
 	"github.com/BurntSushi/toml"
+	govmmQemu "github.com/intel/govmm/qemu"
 	vc "github.com/kata-containers/runtime/virtcontainers"
 	"github.com/kata-containers/runtime/virtcontainers/device/config"
 	exp "github.com/kata-containers/runtime/virtcontainers/experimental"
@@ -595,6 +596,14 @@ func newQemuHypervisorConfig(h hypervisor) (vc.HypervisorConfig, error) {
 	kernelParams := h.kernelParams()
 	machineType := h.machineType()
 
+	// The "microvm" machine type doesn't support NVDIMM so override the
+	// config setting to explicitly disable it (i.e. don't require the
+	// user to add 'disable_image_nvdimm = true' in the .toml file).
+	if machineType == govmmQemu.MachineTypeMicrovm && !h.DisableImageNvdimm {
+		h.DisableImageNvdimm = true
+		kataUtilsLogger.Info("Setting 'disable_image_nvdimm = true' as microvm does not support NVDIMM")
+	}
+
 	blockDriver, err := h.blockDeviceDriver()
 	if err != nil {
 		return vc.HypervisorConfig{}, err
diff --git a/virtcontainers/qemu_amd64.go b/virtcontainers/qemu_amd64.go
index 1a5b266937..0e0d04a73c 100644
--- a/virtcontainers/qemu_amd64.go
+++ b/virtcontainers/qemu_amd64.go
@@ -31,9 +31,10 @@ const (
 )
 
 var qemuPaths = map[string]string{
-	QemuPCLite: "/usr/bin/qemu-lite-system-x86_64",
-	QemuPC:     defaultQemuPath,
-	QemuQ35:    defaultQemuPath,
+	QemuPCLite:  "/usr/bin/qemu-lite-system-x86_64",
+	QemuPC:      defaultQemuPath,
+	QemuQ35:     defaultQemuPath,
+	QemuMicrovm: defaultQemuPath,
 }
 
 var kernelParams = []Param{
@@ -71,6 +72,10 @@ var supportedQemuMachines = []govmmQemu.Machine{
 		Type:    QemuVirt,
 		Options: defaultQemuMachineOptions,
 	},
+	{
+		Type:    QemuMicrovm,
+		Options: defaultQemuMachineOptions,
+	},
 }
 
 // MaxQemuVCPUs returns the maximum number of vCPUs supported
@@ -148,6 +153,12 @@ func (q *qemuAmd64) memoryTopology(memoryMb, hostMemoryMb uint64, slots uint8) g
 	return genericMemoryTopology(memoryMb, hostMemoryMb, slots, q.memoryOffset)
 }
 
+// Is Memory Hotplug supported by this architecture/machine type combination?
+func (q *qemuAmd64) supportGuestMemoryHotplug() bool {
+	// true for all amd64 machine types except for microvm.
+	return q.machineType != govmmQemu.MachineTypeMicrovm
+}
+
 func (q *qemuAmd64) appendImage(devices []govmmQemu.Device, path string) ([]govmmQemu.Device, error) {
 	if !q.disableNvdimm {
 		return q.appendNvdimmImage(devices, path)
diff --git a/virtcontainers/qemu_amd64_test.go b/virtcontainers/qemu_amd64_test.go
index f9d477edc5..86be8fe0fe 100644
--- a/virtcontainers/qemu_amd64_test.go
+++ b/virtcontainers/qemu_amd64_test.go
@@ -37,6 +37,10 @@ func TestQemuAmd64Capabilities(t *testing.T) {
 	amd64 = newTestQemu(QemuQ35)
 	caps = amd64.capabilities()
 	assert.True(caps.IsBlockDeviceHotplugSupported())
+
+	amd64 = newTestQemu(QemuMicrovm)
+	caps = amd64.capabilities()
+	assert.False(caps.IsBlockDeviceHotplugSupported())
 }
 
 func TestQemuAmd64Bridges(t *testing.T) {
@@ -67,6 +71,11 @@ func TestQemuAmd64Bridges(t *testing.T) {
 		assert.NotNil(b.Devices)
 	}
 
+	amd64 = newTestQemu(QemuMicrovm)
+	amd64.bridges(uint32(len))
+	bridges = amd64.getBridges()
+	assert.Nil(bridges)
+
 	amd64 = newTestQemu(QemuQ35 + QemuPC)
 	amd64.bridges(uint32(len))
 	bridges = amd64.getBridges()
@@ -239,3 +248,17 @@ func TestQemuAmd64WithInitrd(t *testing.T) {
 		assert.NotContains(m.Options, qemuNvdimmOption)
 	}
 }
+
+func TestQemuAmd64Microvm(t *testing.T) {
+	assert := assert.New(t)
+
+	cfg := qemuConfig(QemuMicrovm)
+	amd64 := newQemuArch(cfg)
+	assert.False(cfg.DisableImageNvdimm)
+
+	for _, m := range amd64.(*qemuAmd64).supportedQemuMachines {
+		assert.NotContains(m.Options, qemuNvdimmOption)
+	}
+
+	assert.False(amd64.supportGuestMemoryHotplug())
+}
diff --git a/virtcontainers/qemu_arch_base.go b/virtcontainers/qemu_arch_base.go
index 9d72dd09f2..5ea1abb7d7 100644
--- a/virtcontainers/qemu_arch_base.go
+++ b/virtcontainers/qemu_arch_base.go
@@ -175,6 +175,9 @@ const (
 	// QemuQ35 is the QEMU Q35 machine type for amd64
 	QemuQ35 = "q35"
 
+	// QemuMicrovm is the QEMU microvm machine type for amd64
+	QemuMicrovm = "microvm"
+
 	// QemuVirt is the QEMU virt machine type for aarch64 or amd64
 	QemuVirt = "virt"