Fix mount support in QEMU on Windows hosts

On Windows there is native path translation needed from location to
Unix path mountPoint. And another one is needed for location before
passing it to Unix like tooling (sshfs).

Signed-off-by: Arthur Sengileyev <[email protected]>

Author: arixmkii

pkg/hostagent/mount.go

@@ -7,7 +7,9 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"runtime"
 
+	"github.com/lima-vm/lima/pkg/ioutilx"
 	"github.com/lima-vm/lima/pkg/limayaml"
 	"github.com/lima-vm/sshocker/pkg/reversesshfs"
 	"github.com/sirupsen/logrus"
@@ -47,33 +49,42 @@ func (a *HostAgent) setupMount(m limayaml.Mount) (*mount, error) {
 	}
 	logrus.Infof("Mounting %q on %q", m.Location, *m.MountPoint)
 
+	resolvedLocation := m.Location
+	if runtime.GOOS == "windows" {
+		var err error
+		resolvedLocation, err = ioutilx.WindowsSubsystemPath(m.Location)
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	rsf := &reversesshfs.ReverseSSHFS{
 		Driver:              *m.SSHFS.SFTPDriver,
 		SSHConfig:           a.sshConfig,
-		LocalPath:           m.Location,
+		LocalPath:           resolvedLocation,
 		Host:                "127.0.0.1",
 		Port:                a.sshLocalPort,
 		RemotePath:          *m.MountPoint,
 		Readonly:            !(*m.Writable),
 		SSHFSAdditionalArgs: []string{"-o", sshfsOptions},
 	}
 	if err := rsf.Prepare(); err != nil {
-		return nil, fmt.Errorf("failed to prepare reverse sshfs for %q on %q: %w", m.Location, *m.MountPoint, err)
+		return nil, fmt.Errorf("failed to prepare reverse sshfs for %q on %q: %w", resolvedLocation, *m.MountPoint, err)
 	}
 	if err := rsf.Start(); err != nil {
-		logrus.WithError(err).Warnf("failed to mount reverse sshfs for %q on %q, retrying with `-o nonempty`", m.Location, *m.MountPoint)
+		logrus.WithError(err).Warnf("failed to mount reverse sshfs for %q on %q, retrying with `-o nonempty`", resolvedLocation, *m.MountPoint)
 		// NOTE: nonempty is not supported for libfuse3: https://github.com/canonical/multipass/issues/1381
 		rsf.SSHFSAdditionalArgs = []string{"-o", "nonempty"}
 		if err := rsf.Start(); err != nil {
-			return nil, fmt.Errorf("failed to mount reverse sshfs for %q on %q: %w", m.Location, *m.MountPoint, err)
+			return nil, fmt.Errorf("failed to mount reverse sshfs for %q on %q: %w", resolvedLocation, *m.MountPoint, err)
 		}
 	}
 
 	res := &mount{
 		close: func() error {
-			logrus.Infof("Unmounting %q", m.Location)
+			logrus.Infof("Unmounting %q", resolvedLocation)
 			if err := rsf.Close(); err != nil {
-				return fmt.Errorf("failed to unmount reverse sshfs for %q on %q: %w", m.Location, *m.MountPoint, err)
+				return fmt.Errorf("failed to unmount reverse sshfs for %q on %q: %w", resolvedLocation, *m.MountPoint, err)
 			}
 			return nil
 		},

pkg/limayaml/defaults.go

@@ -23,6 +23,7 @@ import (
 	"github.com/coreos/go-semver/semver"
 	"github.com/docker/go-units"
 	"github.com/goccy/go-yaml"
+	"github.com/lima-vm/lima/pkg/ioutilx"
 	"github.com/lima-vm/lima/pkg/version"
 	"github.com/pbnjay/memory"
 	"github.com/sirupsen/logrus"
@@ -830,7 +831,15 @@ func FillDefault(y, d, o *LimaYAML, filePath string, warn bool) {
 			logrus.WithError(err).Warnf("Couldn't expand location %q", mount.Location)
 		}
 		if mount.MountPoint == nil {
-			mounts[i].MountPoint = ptr.Of(mounts[i].Location)
+			mountLocation := mounts[i].Location
+			if runtime.GOOS == "windows" {
+				var err error
+				mountLocation, err = ioutilx.WindowsSubsystemPath(mountLocation)
+				if err != nil {
+					logrus.WithError(err).Warnf("Couldn't convert location %q into mount target", mounts[i].Location)
+				}
+			}
+			mounts[i].MountPoint = ptr.Of(mountLocation)
 		}
 	}
 

pkg/limayaml/defaults_test.go

@@ -15,6 +15,7 @@ import (
 
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
+	"github.com/lima-vm/lima/pkg/ioutilx"
 	"github.com/lima-vm/lima/pkg/osutil"
 	"github.com/lima-vm/lima/pkg/ptr"
 	"github.com/lima-vm/lima/pkg/store/dirnames"
@@ -225,6 +226,12 @@ func TestFillDefault(t *testing.T) {
 
 	expect.Mounts = slices.Clone(y.Mounts)
 	expect.Mounts[0].MountPoint = ptr.Of(expect.Mounts[0].Location)
+	if runtime.GOOS == "windows" {
+		mountLocation, err := ioutilx.WindowsSubsystemPath(expect.Mounts[0].Location)
+		if err == nil {
+			expect.Mounts[0].MountPoint = ptr.Of(mountLocation)
+		}
+	}
 	expect.Mounts[0].Writable = ptr.Of(false)
 	expect.Mounts[0].SSHFS.Cache = ptr.Of(true)
 	expect.Mounts[0].SSHFS.FollowSymlinks = ptr.Of(false)
@@ -464,6 +471,12 @@ func TestFillDefault(t *testing.T) {
 	expect.Containerd.Archives[0].Arch = *d.Arch
 	expect.Mounts = slices.Clone(d.Mounts)
 	expect.Mounts[0].MountPoint = ptr.Of(expect.Mounts[0].Location)
+	if runtime.GOOS == "windows" {
+		mountLocation, err := ioutilx.WindowsSubsystemPath(expect.Mounts[0].Location)
+		if err == nil {
+			expect.Mounts[0].MountPoint = ptr.Of(mountLocation)
+		}
+	}
 	expect.Mounts[0].SSHFS.Cache = ptr.Of(true)
 	expect.Mounts[0].SSHFS.FollowSymlinks = ptr.Of(false)
 	expect.Mounts[0].SSHFS.SFTPDriver = ptr.Of("")