feat: nvme disk on m6

internal/daemon/create.go

@@ -159,9 +159,11 @@ func (d *Daemon) buildMachineSpec(machineID contracthost.MachineID, artifact *mo
 	drives := make([]firecracker.DriveSpec, 0, len(userVolumes))
 	for i, volume := range userVolumes {
 		drives = append(drives, firecracker.DriveSpec{
-			ID:       fmt.Sprintf("user-%d", i),
-			Path:     volume.Path,
-			ReadOnly: false,
+			ID:        fmt.Sprintf("user-%d", i),
+			Path:      volume.Path,
+			ReadOnly:  false,
+			CacheType: firecracker.DriveCacheTypeUnsafe,
+			IOEngine:  d.config.DriveIOEngine,
 		})
 	}
 
@@ -179,9 +181,9 @@ func (d *Daemon) buildMachineSpec(machineID contracthost.MachineID, artifact *mo
 			ID:        "root_drive",
 			Path:      systemVolumePath,
 			CacheType: firecracker.DriveCacheTypeUnsafe,
-			IOEngine:  firecracker.DriveIOEngineSync,
+			IOEngine:  d.config.DriveIOEngine,
 		},
-		KernelArgs: defaultGuestKernelArgs,
+		KernelArgs: guestKernelArgs(d.config.EnablePCI),
 		Drives:     drives,
 		MMDS:       mmds,
 		Vsock:      guestVsockSpec(machineID),

internal/daemon/daemon.go

@@ -8,21 +8,22 @@ import (
 	"sync"
 	"time"
 
-	contracthost "github.com/getcompanion-ai/computer-host/contract"
 	appconfig "github.com/getcompanion-ai/computer-host/internal/config"
 	"github.com/getcompanion-ai/computer-host/internal/firecracker"
 	"github.com/getcompanion-ai/computer-host/internal/model"
 	"github.com/getcompanion-ai/computer-host/internal/store"
+	contracthost "github.com/getcompanion-ai/computer-host/contract"
 )
 
 const (
-	defaultGuestKernelArgs  = "console=ttyS0 reboot=k panic=1 pci=off"
-	defaultGuestMemoryMiB   = int64(3072)
-	defaultGuestVCPUs       = int64(2)
-	defaultSSHPort          = uint16(2222)
-	defaultVNCPort          = uint16(6080)
-	defaultCopyBufferSize   = 1024 * 1024
-	defaultGuestDialTimeout = 500 * time.Millisecond
+	defaultGuestKernelArgs      = "console=ttyS0 reboot=k panic=1"
+	defaultGuestKernelArgsNoPCI = defaultGuestKernelArgs + " pci=off"
+	defaultGuestMemoryMiB       = int64(3072)
+	defaultGuestVCPUs           = int64(2)
+	defaultSSHPort              = uint16(2222)
+	defaultVNCPort              = uint16(6080)
+	defaultCopyBufferSize       = 1024 * 1024
+	defaultGuestDialTimeout     = 500 * time.Millisecond
 )
 
 type Runtime interface {
@@ -73,6 +74,9 @@ func New(cfg appconfig.Config, store store.Store, runtime Runtime) (*Daemon, err
 			return nil, fmt.Errorf("create daemon dir %q: %w", dir, err)
 		}
 	}
+	if err := validateDiskCloneBackend(cfg); err != nil {
+		return nil, err
+	}
 	daemon := &Daemon{
 		config:                   cfg,
 		store:                    store,
@@ -127,3 +131,10 @@ func (d *Daemon) lockArtifact(key string) func() {
 	lock.Lock()
 	return lock.Unlock
 }
+
+func guestKernelArgs(enablePCI bool) string {
+	if enablePCI {
+		return defaultGuestKernelArgs
+	}
+	return defaultGuestKernelArgsNoPCI
+}

internal/daemon/daemon_test.go

@@ -758,6 +758,7 @@ func testConfig(root string) appconfig.Config {
 		SnapshotsDir:          filepath.Join(root, "snapshots"),
 		RuntimeDir:            filepath.Join(root, "runtime"),
 		DiskCloneMode:         appconfig.DiskCloneModeCopy,
+		DriveIOEngine:         firecracker.DriveIOEngineSync,
 		SocketPath:            filepath.Join(root, "firecracker-host.sock"),
 		EgressInterface:       "eth0",
 		FirecrackerBinaryPath: "/usr/bin/firecracker",
@@ -765,6 +766,22 @@ func testConfig(root string) appconfig.Config {
 	}
 }
 
+func TestGuestKernelArgsDisablesPCIByDefault(t *testing.T) {
+	t.Parallel()
+
+	if got := guestKernelArgs(false); !strings.Contains(got, "pci=off") {
+		t.Fatalf("guestKernelArgs(false) = %q, want pci=off", got)
+	}
+}
+
+func TestGuestKernelArgsRemovesPCIOffWhenPCIEnabled(t *testing.T) {
+	t.Parallel()
+
+	if got := guestKernelArgs(true); strings.Contains(got, "pci=off") {
+		t.Fatalf("guestKernelArgs(true) = %q, want no pci=off", got)
+	}
+}
+
 func stubGuestSSHPublicKeyReader(hostDaemon *Daemon) {
 	hostDaemon.readGuestSSHPublicKey = func(context.Context, string) (string, error) {
 		return "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIO0j1AyW0mQm9a1G2rY0R4fP2G5+4Qx2V3FJ9P2mA6N3", nil

internal/daemon/files.go

@@ -97,7 +97,10 @@ func cloneFile(source string, target string) error {
 func cloneDiskFile(source string, target string, mode appconfig.DiskCloneMode) error {
 	switch mode {
 	case appconfig.DiskCloneModeReflink:
-		return reflinkFile(source, target)
+		if err := reflinkFile(source, target); err != nil {
+			return reflinkRequiredError(err)
+		}
+		return nil
 	case appconfig.DiskCloneModeCopy:
 		return cloneFile(source, target)
 	default:
@@ -105,6 +108,42 @@ func cloneDiskFile(source string, target string, mode appconfig.DiskCloneMode) e
 	}
 }
 
+func validateDiskCloneBackend(cfg appconfig.Config) error {
+	if cfg.DiskCloneMode != appconfig.DiskCloneModeReflink {
+		return nil
+	}
+
+	sourceFile, err := os.CreateTemp(cfg.ArtifactsDir, ".reflink-probe-source-*")
+	if err != nil {
+		return fmt.Errorf("create reflink probe source in %q: %w", cfg.ArtifactsDir, err)
+	}
+	sourcePath := sourceFile.Name()
+	defer func() {
+		_ = os.Remove(sourcePath)
+	}()
+
+	if _, err := sourceFile.WriteString("reflink-probe"); err != nil {
+		_ = sourceFile.Close()
+		return fmt.Errorf("write reflink probe source %q: %w", sourcePath, err)
+	}
+	if err := sourceFile.Close(); err != nil {
+		return fmt.Errorf("close reflink probe source %q: %w", sourcePath, err)
+	}
+
+	targetPath := filepath.Join(cfg.MachineDisksDir, "."+filepath.Base(sourcePath)+".target")
+	defer func() {
+		_ = os.Remove(targetPath)
+	}()
+	if err := cloneDiskFile(sourcePath, targetPath, cfg.DiskCloneMode); err != nil {
+		return fmt.Errorf("validate disk clone backend from artifacts dir %q to machine disks dir %q: %w", cfg.ArtifactsDir, cfg.MachineDisksDir, err)
+	}
+	return nil
+}
+
+func reflinkRequiredError(err error) error {
+	return fmt.Errorf("FIRECRACKER_HOST_DISK_CLONE_MODE=reflink requires a CoW filesystem with reflink support across artifacts and machine-disks; mount FIRECRACKER_HOST_ROOT_DIR on XFS with reflink=1 or Btrfs, preferably on local NVMe, or set FIRECRACKER_HOST_DISK_CLONE_MODE=copy for the slow full-copy fallback: %w", err)
+}
+
 func reflinkFile(source string, target string) error {
 	if err := os.MkdirAll(filepath.Dir(target), 0o755); err != nil {
 		return fmt.Errorf("create target dir for %q: %w", target, err)