Optimize QEMU launch and add V-sock support

Refactored QEMU argument construction and launching logic by removing the dependency on 'agent.Computation'. This simplification makes the VM creation process more streamlined. Additionally, introduced V-sock capabilities in the QEMU configuration to facilitate improved guest-host communication. Updated the README to include kernel module setup instructions for the new V-sock feature.

The V-sock implementation enables VMs to use a consistent communication channel that is not affected by network configuration changes, enhancing reliability and potential interoperability with host services. It's important to ensure that the necessary kernel modules are loaded as part of the setup process, as documented.

Signed-off-by: SammyOina <sammyoina@gmail.com>

cmd/manager/main.go

@@ -12,7 +12,6 @@ import (
 
 	mglog "github.com/absmach/magistrala/logger"
 	"github.com/absmach/magistrala/pkg/uuid"
-	"github.com/ultravioletrs/cocos/agent"
 	"github.com/ultravioletrs/cocos/internal"
 	"github.com/ultravioletrs/cocos/internal/env"
 	"github.com/ultravioletrs/cocos/internal/events"
@@ -86,7 +85,7 @@ func main() {
 	if err := env.Parse(&qemuCfg, env.Options{Prefix: envPrefixQemu}); err != nil {
 		logger.Fatal(fmt.Sprintf("failed to load QEMU configuration: %s", err))
 	}
-	exe, args, err := qemu.ExecutableAndArgs(qemuCfg, agent.Computation{})
+	exe, args, err := qemu.ExecutableAndArgs(qemuCfg)
 	if err != nil {
 		logger.Fatal(fmt.Sprintf("failed to parse QEMU configuration: %s", err))
 	}

manager/README.md

@@ -47,6 +47,17 @@ sudo apt install qemu-kvm
 
 Create `img` directory in `cmd/manager`. Create `tmp` directory in `cmd/manager`.
 
+#### Add V-sock
+The necessary kernel modules must be loaded on the hypervisor.
+```shell
+sudo modprobe vhost_vsock
+ls -l /dev/vhost-vsock
+# crw-rw-rw- 1 root kvm 10, 241 Jan 16 12:05 /dev/vhost-vsock
+ls -l /dev/vsock
+# crw-rw-rw- 1 root root 10, 121 Jan 16 12:05 /dev/vsock
+```
+
+
 ### Prepare Cocos HAL
 
 Cocos HAL for Linux is framework for building custom in-enclave Linux distribution. Use the instructions in [Readme](https://github.com/ultravioletrs/cocos/blob/main/hal/linux/README.md).
@@ -78,8 +89,9 @@ qemu-system-x86_64 \
     -drive if=pflash,format=raw,unit=0,file=$OVMF_CODE,readonly=on \
     -netdev user,id=vmnic,hostfwd=tcp::2222-:22,hostfwd=tcp::9301-:9031,hostfwd=tcp::7020-:7002 \
     -device virtio-net-pci,disable-legacy=on,iommu_platform=true,netdev=vmnic,romfile= \
+    -device vhost-vsock-pci,id=vhost-vsock-pci0,guest-cid=3 -vnc :0 \
     -kernel $KERNEL \
-    -append "earlyprintk=serial console=ttyS0 computation={\"id\":\"c0d15c5e-e37d-4426-b3b7-b432c966fb09\",\"name\":\"Sample_Computation\",\"description\":\"A_sample_computation\",\"datasets\":[{\"provider\":\"Provider1\",\"id\":\"Dataset1\"},{\"provider\":\"Provider2\",\"id\":\"Dataset2\"}],\"algorithms\":[{\"provider\":\"AlgorithmProvider1\",\"id\":\"Algorithm1\"}],\"result_consumers\":[\"Consumer1\"], \"timeout\":\"10m\"}" \
+    -append "earlyprintk=serial console=ttyS0" \
     -initrd $INITRD \
     -nographic \
     -monitor pty \

manager/qemu/config.go

@@ -56,6 +56,12 @@ type SevConfig struct {
 	ReducedPhysBits int    `env:"SEV_REDUCED_PHYS_BITS" envDefault:"1"`
 }
 
+type VSockConfig struct {
+	ID       string `env:"VSOCK_ID"        envDefault:"vhost-vsock-pci0"`
+	GuestCID int    `env:"VSOCK_GUEST_CID" envDefault:"3"`
+	vnc      int    `env:"VSOCK_VNC"       envDefault:"0"`
+}
+
 type Config struct {
 	TmpFileLoc string `env:"TMP_FILE_LOC" envDefault:"tmp"`
 	UseSudo    bool   `env:"USE_SUDO" envDefault:"false"`
@@ -78,6 +84,9 @@ type Config struct {
 	NetDevConfig
 	VirtioNetPciConfig
 
+	// Vsock
+	VSockConfig
+
 	// disk
 	VirtioScsiPciConfig
 	DiskImgConfig
@@ -90,7 +99,7 @@ type Config struct {
 	Monitor   string `env:"MONITOR" envDefault:"pty"`
 }
 
-func constructQemuArgs(config Config, computation string) []string {
+func constructQemuArgs(config Config) []string {
 	args := []string{}
 
 	// virtualization
@@ -137,9 +146,11 @@ func constructQemuArgs(config Config, computation string) []string {
 			config.VirtioScsiPciConfig.DisableLegacy,
 			config.VirtioScsiPciConfig.IOMMUPlatform))
 
+	args = append(args, "-device", fmt.Sprintf("vhost-vsock-pci,id=%s,guest-cid=%d -vnc :%d", config.VSockConfig.ID, config.VSockConfig.GuestCID, config.VSockConfig.vnc))
+
 	args = append(args, "-kernel", config.DiskImgConfig.KernelFile)
 
-	args = append(args, "-append", fmt.Sprintf("earlyprintk=serial console=ttyS0 computation=%s", computation))
+	args = append(args, "-append", "earlyprintk=serial console=ttyS0")
 
 	args = append(args, "-initrd", config.DiskImgConfig.RootFsFile)
 

manager/qemu/qemu.go

@@ -4,13 +4,10 @@ package qemu
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"os/exec"
-	"strconv"
 
 	"github.com/gofrs/uuid"
-	"github.com/ultravioletrs/cocos/agent"
 	"github.com/ultravioletrs/cocos/internal"
 )
 
@@ -21,7 +18,7 @@ const (
 	rootfsFile   = "rootfs.cpio"
 )
 
-func CreateVM(ctx context.Context, cfg Config, ac agent.Computation) (*exec.Cmd, error) {
+func CreateVM(ctx context.Context, cfg Config) (*exec.Cmd, error) {
 	// Create unique emu device identifiers.
 	id, err := uuid.NewV4()
 	if err != nil {
@@ -58,7 +55,7 @@ func CreateVM(ctx context.Context, cfg Config, ac agent.Computation) (*exec.Cmd,
 	}
 	qemuCfg.DiskImgConfig.RootFsFile = dstFile
 
-	exe, args, err := ExecutableAndArgs(qemuCfg, ac)
+	exe, args, err := ExecutableAndArgs(qemuCfg)
 	if err != nil {
 		return &exec.Cmd{}, err
 	}
@@ -70,18 +67,13 @@ func CreateVM(ctx context.Context, cfg Config, ac agent.Computation) (*exec.Cmd,
 	return cmd, nil
 }
 
-func ExecutableAndArgs(cfg Config, ac agent.Computation) (string, []string, error) {
+func ExecutableAndArgs(cfg Config) (string, []string, error) {
 	exe, err := exec.LookPath(qemuRelPath)
 	if err != nil {
 		return "", nil, err
 	}
 
-	cmpBytes, err := json.Marshal(ac)
-	if err != nil {
-		return "", nil, err
-	}
-
-	args := constructQemuArgs(cfg, strconv.Quote(string(cmpBytes)))
+	args := constructQemuArgs(cfg)
 
 	if cfg.UseSudo {
 		args = append([]string{exe}, args...)

manager/service.go

@@ -80,7 +80,7 @@ func (ms *managerService) Run(ctx context.Context, c *Computation) (string, erro
 	ms.qemuCfg.HostFwdAgent = agentPort
 
 	ms.publishEvent("vm-provision", c.Id, "in-progress", json.RawMessage{})
-	if _, err = qemu.CreateVM(ctx, ms.qemuCfg, ac); err != nil {
+	if _, err = qemu.CreateVM(ctx, ms.qemuCfg); err != nil {
 		ms.publishEvent("vm-provision", c.Id, "failed", json.RawMessage{})
 		return "", err
 	}

manager/vsock.go

@@ -0,0 +1 @@
+package manager