pkg/containerfs: alias ContainerFS to string

Drop the constructor and redundant string() type-casts.

Signed-off-by: Cory Snider <csnider@mirantis.com>

17 files changed, 73 insertions, 87 deletions

diff --git a/daemon/graphdriver/aufs/aufs.go b/daemon/graphdriver/aufs/aufs.go
index 08ab302bb1..8066549a62 100644
--- a/daemon/graphdriver/aufs/aufs.go
+++ b/daemon/graphdriver/aufs/aufs.go
@@ -370,7 +370,7 @@ func (a *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 		}
 	}
 	if count := a.ctr.Increment(m); count > 1 {
-		return containerfs.NewLocalContainerFS(m), nil
+		return m, nil
 	}
 
 	// If a dir does not have a parent ( no layers )do not try to mount
@@ -384,7 +384,7 @@ func (a *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 	a.pathCacheLock.Lock()
 	a.pathCache[id] = m
 	a.pathCacheLock.Unlock()
-	return containerfs.NewLocalContainerFS(m), nil
+	return m, nil
 }
 
 // Put unmounts and updates list of active mounts.
diff --git a/daemon/graphdriver/aufs/aufs_test.go b/daemon/graphdriver/aufs/aufs_test.go
index 05c2ed778d..26142acfc5 100644
--- a/daemon/graphdriver/aufs/aufs_test.go
+++ b/daemon/graphdriver/aufs/aufs_test.go
@@ -43,14 +43,6 @@ func testInit(dir string, t testing.TB) graphdriver.Driver {
 	return d
 }
 
-func driverGet(d *Driver, id string, mntLabel string) (string, error) {
-	mnt, err := d.Get(id, mntLabel)
-	if err != nil {
-		return "", err
-	}
-	return string(mnt), nil
-}
-
 func newDriver(t testing.TB) *Driver {
 	if err := os.MkdirAll(tmp, 0755); err != nil {
 		t.Fatal(err)
@@ -180,7 +172,7 @@ func TestGetWithoutParent(t *testing.T) {
 		t.Fatal(err)
 	}
 	expected := path.Join(tmp, "diff", "1")
-	if string(diffPath) != expected {
+	if diffPath != expected {
 		t.Fatalf("Expected path %s got %s", expected, diffPath)
 	}
 }
@@ -262,8 +254,8 @@ func TestMountWithParent(t *testing.T) {
 	}
 
 	expected := path.Join(tmp, "mnt", "2")
-	if string(mntPath) != expected {
-		t.Fatalf("Expected %s got %s", expected, string(mntPath))
+	if mntPath != expected {
+		t.Fatalf("Expected %s got %s", expected, mntPath)
 	}
 }
 
@@ -323,7 +315,7 @@ func TestGetDiff(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	diffPath, err := driverGet(d, "1", "")
+	diffPath, err := d.Get("1", "")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -367,7 +359,7 @@ func TestChanges(t *testing.T) {
 		}
 	}()
 
-	mntPoint, err := driverGet(d, "2", "")
+	mntPoint, err := d.Get("2", "")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -406,7 +398,7 @@ func TestChanges(t *testing.T) {
 	if err := d.CreateReadWrite("3", "2", nil); err != nil {
 		t.Fatal(err)
 	}
-	mntPoint, err = driverGet(d, "3", "")
+	mntPoint, err = d.Get("3", "")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -452,7 +444,7 @@ func TestDiffSize(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	diffPath, err := driverGet(d, "1", "")
+	diffPath, err := d.Get("1", "")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -494,7 +486,7 @@ func TestChildDiffSize(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	diffPath, err := driverGet(d, "1", "")
+	diffPath, err := d.Get("1", "")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -595,7 +587,7 @@ func TestApplyDiff(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	diffPath, err := driverGet(d, "1", "")
+	diffPath, err := d.Get("1", "")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -630,7 +622,7 @@ func TestApplyDiff(t *testing.T) {
 
 	// Ensure that the file is in the mount point for id 3
 
-	mountPoint, err := driverGet(d, "3", "")
+	mountPoint, err := d.Get("3", "")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -673,7 +665,7 @@ func testMountMoreThan42Layers(t *testing.T, mountPath string) {
 		err := d.CreateReadWrite(current, parent, nil)
 		assert.NilError(t, err, "current layer %d", i)
 
-		point, err := driverGet(d, current, "")
+		point, err := d.Get(current, "")
 		assert.NilError(t, err, "current layer %d", i)
 
 		f, err := os.Create(path.Join(point, current))
@@ -689,7 +681,7 @@ func testMountMoreThan42Layers(t *testing.T, mountPath string) {
 	}
 
 	// Perform the actual mount for the top most image
-	point, err := driverGet(d, last, "")
+	point, err := d.Get(last, "")
 	assert.NilError(t, err)
 	files, err := os.ReadDir(point)
 	assert.NilError(t, err)
diff --git a/daemon/graphdriver/btrfs/btrfs.go b/daemon/graphdriver/btrfs/btrfs.go
index f0bf1ab54d..8373d921a5 100644
--- a/daemon/graphdriver/btrfs/btrfs.go
+++ b/daemon/graphdriver/btrfs/btrfs.go
@@ -649,7 +649,7 @@ func (d *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 		}
 	}
 
-	return containerfs.NewLocalContainerFS(dir), nil
+	return dir, nil
 }
 
 // Put is not implemented for BTRFS as there is no cleanup required for the id.
diff --git a/daemon/graphdriver/btrfs/btrfs_test.go b/daemon/graphdriver/btrfs/btrfs_test.go
index 05d0f48e9c..511f29af7d 100644
--- a/daemon/graphdriver/btrfs/btrfs_test.go
+++ b/daemon/graphdriver/btrfs/btrfs_test.go
@@ -36,14 +36,12 @@ func TestBtrfsSubvolDelete(t *testing.T) {
 	}
 	defer graphtest.PutDriver(t)
 
-	dirFS, err := d.Get("test", "")
+	dir, err := d.Get("test", "")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer d.Put("test")
 
-	dir := string(dirFS)
-
 	if err := subvolCreate(dir, "subvoltest"); err != nil {
 		t.Fatal(err)
 	}
diff --git a/daemon/graphdriver/devmapper/driver.go b/daemon/graphdriver/devmapper/driver.go
index ec8c20d513..894345e468 100644
--- a/daemon/graphdriver/devmapper/driver.go
+++ b/daemon/graphdriver/devmapper/driver.go
@@ -181,7 +181,7 @@ func (d *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 	mp := path.Join(d.home, "mnt", id)
 	rootFs := path.Join(mp, "rootfs")
 	if count := d.ctr.Increment(mp); count > 1 {
-		return containerfs.NewLocalContainerFS(rootFs), nil
+		return rootFs, nil
 	}
 
 	root := d.idMap.RootPair()
@@ -219,7 +219,7 @@ func (d *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 		}
 	}
 
-	return containerfs.NewLocalContainerFS(rootFs), nil
+	return rootFs, nil
 }
 
 // Put unmounts a device and removes it.
diff --git a/daemon/graphdriver/fsdiff.go b/daemon/graphdriver/fsdiff.go
index 331d60d392..2a201dc2f5 100644
--- a/daemon/graphdriver/fsdiff.go
+++ b/daemon/graphdriver/fsdiff.go
@@ -50,7 +50,7 @@ func (gdw *NaiveDiffDriver) Diff(id, parent string) (arch io.ReadCloser, err err
 	if err != nil {
 		return nil, err
 	}
-	layerFs := string(layerRootFs)
+	layerFs := layerRootFs
 
 	defer func() {
 		if err != nil {
@@ -70,14 +70,12 @@ func (gdw *NaiveDiffDriver) Diff(id, parent string) (arch io.ReadCloser, err err
 		}), nil
 	}
 
-	parentRootFs, err := driver.Get(parent, "")
+	parentFs, err := driver.Get(parent, "")
 	if err != nil {
 		return nil, err
 	}
 	defer driver.Put(parent)
 
-	parentFs := string(parentRootFs)
-
 	changes, err := archive.ChangesDirs(layerFs, parentFs)
 	if err != nil {
 		return nil, err
@@ -106,22 +104,20 @@ func (gdw *NaiveDiffDriver) Diff(id, parent string) (arch io.ReadCloser, err err
 func (gdw *NaiveDiffDriver) Changes(id, parent string) ([]archive.Change, error) {
 	driver := gdw.ProtoDriver
 
-	layerRootFs, err := driver.Get(id, "")
+	layerFs, err := driver.Get(id, "")
 	if err != nil {
 		return nil, err
 	}
 	defer driver.Put(id)
 
-	layerFs := string(layerRootFs)
 	parentFs := ""
 
 	if parent != "" {
-		parentRootFs, err := driver.Get(parent, "")
+		parentFs, err = driver.Get(parent, "")
 		if err != nil {
 			return nil, err
 		}
 		defer driver.Put(parent)
-		parentFs = string(parentRootFs)
 	}
 
 	return archive.ChangesDirs(layerFs, parentFs)
@@ -140,7 +136,7 @@ func (gdw *NaiveDiffDriver) ApplyDiff(id, parent string, diff io.Reader) (size i
 	}
 	defer driver.Put(id)
 
-	layerFs := string(layerRootFs)
+	layerFs := layerRootFs
 	options := &archive.TarOptions{IDMap: gdw.idMap}
 	start := time.Now().UTC()
 	logrus.WithField("id", id).Debug("Start untar layer")
@@ -169,5 +165,5 @@ func (gdw *NaiveDiffDriver) DiffSize(id, parent string) (size int64, err error)
 	}
 	defer driver.Put(id)
 
-	return archive.ChangesSize(string(layerFs), changes), nil
+	return archive.ChangesSize(layerFs, changes), nil
 }
diff --git a/daemon/graphdriver/fuse-overlayfs/fuseoverlayfs.go b/daemon/graphdriver/fuse-overlayfs/fuseoverlayfs.go
index a39d58d327..aa7799e1c9 100644
--- a/daemon/graphdriver/fuse-overlayfs/fuseoverlayfs.go
+++ b/daemon/graphdriver/fuse-overlayfs/fuseoverlayfs.go
@@ -316,14 +316,14 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, retErr e
 	if err != nil {
 		// If no lower, just return diff directory
 		if os.IsNotExist(err) {
-			return containerfs.NewLocalContainerFS(diffDir), nil
+			return diffDir, nil
 		}
 		return "", err
 	}
 
 	mergedDir := path.Join(dir, mergedDirName)
 	if count := d.ctr.Increment(mergedDir); count > 1 {
-		return containerfs.NewLocalContainerFS(mergedDir), nil
+		return mergedDir, nil
 	}
 	defer func() {
 		if retErr != nil {
@@ -380,7 +380,7 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, retErr e
 		return "", errors.Wrapf(err, "using mount program %s: %s", binary, output)
 	}
 
-	return containerfs.NewLocalContainerFS(mergedDir), nil
+	return mergedDir, nil
 }
 
 // Put unmounts the mount path created for the give id.
diff --git a/daemon/graphdriver/graphtest/graphbench_unix.go b/daemon/graphdriver/graphtest/graphbench_unix.go
index 88ca80005a..422c3ec23d 100644
--- a/daemon/graphdriver/graphtest/graphbench_unix.go
+++ b/daemon/graphdriver/graphtest/graphbench_unix.go
@@ -250,7 +250,7 @@ func DriverBenchDeepLayerRead(b *testing.B, layerCount int, drivername string, d
 	for i := 0; i < b.N; i++ {
 
 		// Read content
-		c, err := os.ReadFile(filepath.Join(string(root), "testfile.txt"))
+		c, err := os.ReadFile(filepath.Join(root, "testfile.txt"))
 		if err != nil {
 			b.Fatal(err)
 		}
diff --git a/daemon/graphdriver/graphtest/graphtest_unix.go b/daemon/graphdriver/graphtest/graphtest_unix.go
index f8fa88dcc6..b0b93d281d 100644
--- a/daemon/graphdriver/graphtest/graphtest_unix.go
+++ b/daemon/graphdriver/graphtest/graphtest_unix.go
@@ -96,10 +96,10 @@ func DriverTestCreateEmpty(t testing.TB, drivername string, driverOptions ...str
 	dir, err := driver.Get("empty", "")
 	assert.NilError(t, err)
 
-	verifyFile(t, string(dir), 0755|os.ModeDir, 0, 0)
+	verifyFile(t, dir, 0755|os.ModeDir, 0, 0)
 
 	// Verify that the directory is empty
-	fis, err := readDir(string(dir))
+	fis, err := readDir(dir)
 	assert.NilError(t, err)
 	assert.Check(t, is.Len(fis, 0))
 
@@ -324,19 +324,19 @@ func DriverTestSetQuota(t *testing.T, drivername string, required bool) {
 	quota := uint64(50 * units.MiB)
 
 	// Try to write a file smaller than quota, and ensure it works
-	err = writeRandomFile(path.Join(string(mountPath), "smallfile"), quota/2)
+	err = writeRandomFile(path.Join(mountPath, "smallfile"), quota/2)
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer os.Remove(path.Join(string(mountPath), "smallfile"))
+	defer os.Remove(path.Join(mountPath, "smallfile"))
 
 	// Try to write a file bigger than quota. We've already filled up half the quota, so hitting the limit should be easy
-	err = writeRandomFile(path.Join(string(mountPath), "bigfile"), quota)
+	err = writeRandomFile(path.Join(mountPath, "bigfile"), quota)
 	if err == nil {
 		t.Fatalf("expected write to fail(), instead had success")
 	}
 	if pathError, ok := err.(*os.PathError); ok && pathError.Err != unix.EDQUOT && pathError.Err != unix.ENOSPC {
-		os.Remove(path.Join(string(mountPath), "bigfile"))
+		os.Remove(path.Join(mountPath, "bigfile"))
 		t.Fatalf("expect write() to fail with %v or %v, got %v", unix.EDQUOT, unix.ENOSPC, pathError.Err)
 	}
 }
diff --git a/daemon/graphdriver/graphtest/testutil.go b/daemon/graphdriver/graphtest/testutil.go
index 6f02c5645b..20a0da8b31 100644
--- a/daemon/graphdriver/graphtest/testutil.go
+++ b/daemon/graphdriver/graphtest/testutil.go
@@ -36,17 +36,17 @@ func addFiles(drv graphdriver.Driver, layer string, seed int64) error {
 	}
 	defer drv.Put(layer)
 
-	if err := os.WriteFile(filepath.Join(string(root), "file-a"), randomContent(64, seed), 0755); err != nil {
+	if err := os.WriteFile(filepath.Join(root, "file-a"), randomContent(64, seed), 0755); err != nil {
 		return err
 	}
-	if err := os.MkdirAll(filepath.Join(string(root), "dir-b"), 0755); err != nil {
+	if err := os.MkdirAll(filepath.Join(root, "dir-b"), 0755); err != nil {
 		return err
 	}
-	if err := os.WriteFile(filepath.Join(string(root), "dir-b", "file-b"), randomContent(128, seed+1), 0755); err != nil {
+	if err := os.WriteFile(filepath.Join(root, "dir-b", "file-b"), randomContent(128, seed+1), 0755); err != nil {
 		return err
 	}
 
-	return os.WriteFile(filepath.Join(string(root), "file-c"), randomContent(128*128, seed+2), 0755)
+	return os.WriteFile(filepath.Join(root, "file-c"), randomContent(128*128, seed+2), 0755)
 }
 
 func checkFile(drv graphdriver.Driver, layer, filename string, content []byte) error {
@@ -56,7 +56,7 @@ func checkFile(drv graphdriver.Driver, layer, filename string, content []byte) e
 	}
 	defer drv.Put(layer)
 
-	fileContent, err := os.ReadFile(filepath.Join(string(root), filename))
+	fileContent, err := os.ReadFile(filepath.Join(root, filename))
 	if err != nil {
 		return err
 	}
@@ -75,7 +75,7 @@ func addFile(drv graphdriver.Driver, layer, filename string, content []byte) err
 	}
 	defer drv.Put(layer)
 
-	return os.WriteFile(filepath.Join(string(root), filename), content, 0755)
+	return os.WriteFile(filepath.Join(root, filename), content, 0755)
 }
 
 func addDirectory(drv graphdriver.Driver, layer, dir string) error {
@@ -85,7 +85,7 @@ func addDirectory(drv graphdriver.Driver, layer, dir string) error {
 	}
 	defer drv.Put(layer)
 
-	return os.MkdirAll(filepath.Join(string(root), dir), 0755)
+	return os.MkdirAll(filepath.Join(root, dir), 0755)
 }
 
 func removeAll(drv graphdriver.Driver, layer string, names ...string) error {
@@ -96,7 +96,7 @@ func removeAll(drv graphdriver.Driver, layer string, names ...string) error {
 	defer drv.Put(layer)
 
 	for _, filename := range names {
-		if err := os.RemoveAll(filepath.Join(string(root), filename)); err != nil {
+		if err := os.RemoveAll(filepath.Join(root, filename)); err != nil {
 			return err
 		}
 	}
@@ -110,8 +110,8 @@ func checkFileRemoved(drv graphdriver.Driver, layer, filename string) error {
 	}
 	defer drv.Put(layer)
 
-	if _, err := os.Stat(filepath.Join(string(root), filename)); err == nil {
-		return fmt.Errorf("file still exists: %s", filepath.Join(string(root), filename))
+	if _, err := os.Stat(filepath.Join(root, filename)); err == nil {
+		return fmt.Errorf("file still exists: %s", filepath.Join(root, filename))
 	} else if !os.IsNotExist(err) {
 		return err
 	}
@@ -127,7 +127,7 @@ func addManyFiles(drv graphdriver.Driver, layer string, count int, seed int64) e
 	defer drv.Put(layer)
 
 	for i := 0; i < count; i += 100 {
-		dir := filepath.Join(string(root), fmt.Sprintf("directory-%d", i))
+		dir := filepath.Join(root, fmt.Sprintf("directory-%d", i))
 		if err := os.MkdirAll(dir, 0755); err != nil {
 			return err
 		}
@@ -152,7 +152,7 @@ func changeManyFiles(drv graphdriver.Driver, layer string, count int, seed int64
 	var changes []archive.Change
 	for i := 0; i < count; i += 100 {
 		archiveRoot := fmt.Sprintf("/directory-%d", i)
-		if err := os.MkdirAll(filepath.Join(string(root), archiveRoot), 0755); err != nil {
+		if err := os.MkdirAll(filepath.Join(root, archiveRoot), 0755); err != nil {
 			return nil, err
 		}
 		for j := 0; i+j < count && j < 100; j++ {
@@ -168,21 +168,21 @@ func changeManyFiles(drv graphdriver.Driver, layer string, count int, seed int64
 			case 0:
 				change.Path = filepath.Join(archiveRoot, fmt.Sprintf("file-%d", i+j))
 				change.Kind = archive.ChangeModify
-				if err := os.WriteFile(filepath.Join(string(root), change.Path), randomContent(64, seed+int64(i+j)), 0755); err != nil {
+				if err := os.WriteFile(filepath.Join(root, change.Path), randomContent(64, seed+int64(i+j)), 0755); err != nil {
 					return nil, err
 				}
 			// Add file
 			case 1:
 				change.Path = filepath.Join(archiveRoot, fmt.Sprintf("file-%d-%d", seed, i+j))
 				change.Kind = archive.ChangeAdd
-				if err := os.WriteFile(filepath.Join(string(root), change.Path), randomContent(64, seed+int64(i+j)), 0755); err != nil {
+				if err := os.WriteFile(filepath.Join(root, change.Path), randomContent(64, seed+int64(i+j)), 0755); err != nil {
 					return nil, err
 				}
 			// Remove file
 			case 2:
 				change.Path = filepath.Join(archiveRoot, fmt.Sprintf("file-%d", i+j))
 				change.Kind = archive.ChangeDelete
-				if err := os.Remove(filepath.Join(string(root), change.Path)); err != nil {
+				if err := os.Remove(filepath.Join(root, change.Path)); err != nil {
 					return nil, err
 				}
 			}
@@ -201,7 +201,7 @@ func checkManyFiles(drv graphdriver.Driver, layer string, count int, seed int64)
 	defer drv.Put(layer)
 
 	for i := 0; i < count; i += 100 {
-		dir := filepath.Join(string(root), fmt.Sprintf("directory-%d", i))
+		dir := filepath.Join(root, fmt.Sprintf("directory-%d", i))
 		for j := 0; i+j < count && j < 100; j++ {
 			file := filepath.Join(dir, fmt.Sprintf("file-%d", i+j))
 			fileContent, err := os.ReadFile(file)
@@ -254,10 +254,10 @@ func addLayerFiles(drv graphdriver.Driver, layer, parent string, i int) error {
 	}
 	defer drv.Put(layer)
 
-	if err := os.WriteFile(filepath.Join(string(root), "top-id"), []byte(layer), 0755); err != nil {
+	if err := os.WriteFile(filepath.Join(root, "top-id"), []byte(layer), 0755); err != nil {
 		return err
 	}
-	layerDir := filepath.Join(string(root), fmt.Sprintf("layer-%d", i))
+	layerDir := filepath.Join(root, fmt.Sprintf("layer-%d", i))
 	if err := os.MkdirAll(layerDir, 0755); err != nil {
 		return err
 	}
@@ -291,7 +291,7 @@ func checkManyLayers(drv graphdriver.Driver, layer string, count int) error {
 	}
 	defer drv.Put(layer)
 
-	layerIDBytes, err := os.ReadFile(filepath.Join(string(root), "top-id"))
+	layerIDBytes, err := os.ReadFile(filepath.Join(root, "top-id"))
 	if err != nil {
 		return err
 	}
@@ -301,7 +301,7 @@ func checkManyLayers(drv graphdriver.Driver, layer string, count int) error {
 	}
 
 	for i := count; i > 0; i-- {
-		layerDir := filepath.Join(string(root), fmt.Sprintf("layer-%d", i))
+		layerDir := filepath.Join(root, fmt.Sprintf("layer-%d", i))
 
 		thisLayerIDBytes, err := os.ReadFile(filepath.Join(layerDir, "layer-id"))
 		if err != nil {
diff --git a/daemon/graphdriver/graphtest/testutil_unix.go b/daemon/graphdriver/graphtest/testutil_unix.go
index e8b0f8786f..d42682203e 100644
--- a/daemon/graphdriver/graphtest/testutil_unix.go
+++ b/daemon/graphdriver/graphtest/testutil_unix.go
@@ -45,11 +45,11 @@ func createBase(t testing.TB, driver graphdriver.Driver, name string) {
 	assert.NilError(t, err)
 	defer driver.Put(name)
 
-	subdir := filepath.Join(string(dirFS), "a subdir")
+	subdir := filepath.Join(dirFS, "a subdir")
 	assert.NilError(t, os.Mkdir(subdir, 0705|os.ModeSticky))
 	assert.NilError(t, contdriver.LocalDriver.Lchown(subdir, 1, 2))
 
-	file := filepath.Join(string(dirFS), "a file")
+	file := filepath.Join(dirFS, "a file")
 	err = os.WriteFile(file, []byte("Some data"), 0222|os.ModeSetuid)
 	assert.NilError(t, err)
 }
@@ -59,13 +59,13 @@ func verifyBase(t testing.TB, driver graphdriver.Driver, name string) {
 	assert.NilError(t, err)
 	defer driver.Put(name)
 
-	subdir := filepath.Join(string(dirFS), "a subdir")
+	subdir := filepath.Join(dirFS, "a subdir")
 	verifyFile(t, subdir, 0705|os.ModeDir|os.ModeSticky, 1, 2)
 
-	file := filepath.Join(string(dirFS), "a file")
+	file := filepath.Join(dirFS, "a file")
 	verifyFile(t, file, 0222|os.ModeSetuid, 0, 0)
 
-	files, err := readDir(string(dirFS))
+	files, err := readDir(dirFS)
 	assert.NilError(t, err)
 	assert.Check(t, is.Len(files, 2))
 }
diff --git a/daemon/graphdriver/overlay/overlay.go b/daemon/graphdriver/overlay/overlay.go
index 9c23dc0c15..01d4982e12 100644
--- a/daemon/graphdriver/overlay/overlay.go
+++ b/daemon/graphdriver/overlay/overlay.go
@@ -349,12 +349,12 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, err erro
 	// If id has a root, just return it
 	rootDir := path.Join(dir, "root")
 	if _, err := os.Stat(rootDir); err == nil {
-		return containerfs.NewLocalContainerFS(rootDir), nil
+		return rootDir, nil
 	}
 
 	mergedDir := path.Join(dir, "merged")
 	if count := d.ctr.Increment(mergedDir); count > 1 {
-		return containerfs.NewLocalContainerFS(mergedDir), nil
+		return mergedDir, nil
 	}
 	defer func() {
 		if err != nil {
@@ -391,7 +391,7 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, err erro
 	if err := root.Chown(path.Join(workDir, "work")); err != nil {
 		return "", err
 	}
-	return containerfs.NewLocalContainerFS(mergedDir), nil
+	return mergedDir, nil
 }
 
 // Put unmounts the mount path created for the give id.
diff --git a/daemon/graphdriver/overlay2/overlay.go b/daemon/graphdriver/overlay2/overlay.go
index b4b807e796..9140ea089f 100644
--- a/daemon/graphdriver/overlay2/overlay.go
+++ b/daemon/graphdriver/overlay2/overlay.go
@@ -526,14 +526,14 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, retErr e
 	if err != nil {
 		// If no lower, just return diff directory
 		if os.IsNotExist(err) {
-			return containerfs.NewLocalContainerFS(diffDir), nil
+			return diffDir, nil
 		}
 		return "", err
 	}
 
 	mergedDir := path.Join(dir, mergedDirName)
 	if count := d.ctr.Increment(mergedDir); count > 1 {
-		return containerfs.NewLocalContainerFS(mergedDir), nil
+		return mergedDir, nil
 	}
 	defer func() {
 		if retErr != nil {
@@ -613,7 +613,7 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, retErr e
 		}
 	}
 
-	return containerfs.NewLocalContainerFS(mergedDir), nil
+	return mergedDir, nil
 }
 
 // Put unmounts the mount path created for the give id.
diff --git a/daemon/graphdriver/proxy.go b/daemon/graphdriver/proxy.go
index 17abfca6d4..94185131d0 100644
--- a/daemon/graphdriver/proxy.go
+++ b/daemon/graphdriver/proxy.go
@@ -141,7 +141,7 @@ func (d *graphDriverProxy) Get(id, mountLabel string) (containerfs.ContainerFS,
 	if ret.Err != "" {
 		err = errors.New(ret.Err)
 	}
-	return containerfs.NewLocalContainerFS(d.p.ScopedPath(ret.Dir)), err
+	return d.p.ScopedPath(ret.Dir), err
 }
 
 func (d *graphDriverProxy) Put(id string) error {
diff --git a/daemon/graphdriver/vfs/driver.go b/daemon/graphdriver/vfs/driver.go
index 92e2f115ec..d99b82e833 100644
--- a/daemon/graphdriver/vfs/driver.go
+++ b/daemon/graphdriver/vfs/driver.go
@@ -172,7 +172,7 @@ func (d *Driver) create(id, parent string, size uint64) error {
 	if err != nil {
 		return fmt.Errorf("%s: %s", parent, err)
 	}
-	return CopyDir(string(parentDir), dir)
+	return CopyDir(parentDir, dir)
 }
 
 func (d *Driver) dir(id string) string {
@@ -192,7 +192,7 @@ func (d *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 	} else if !st.IsDir() {
 		return "", fmt.Errorf("%s: not a directory", dir)
 	}
-	return containerfs.NewLocalContainerFS(dir), nil
+	return dir, nil
 }
 
 // Put is a noop for vfs that return nil for the error, since this driver has no runtime resources to clean up.
diff --git a/daemon/graphdriver/windows/windows.go b/daemon/graphdriver/windows/windows.go
index 4c89cfe97e..383c3b7473 100644
--- a/daemon/graphdriver/windows/windows.go
+++ b/daemon/graphdriver/windows/windows.go
@@ -402,7 +402,7 @@ func (d *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 		return "", err
 	}
 	if count := d.ctr.Increment(rID); count > 1 {
-		return containerfs.NewLocalContainerFS(d.cache[rID]), nil
+		return d.cache[rID], nil
 	}
 
 	// Getting the layer paths must be done outside of the lock.
@@ -447,7 +447,7 @@ func (d *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
 		dir = d.dir(id)
 	}
 
-	return containerfs.NewLocalContainerFS(dir), nil
+	return dir, nil
 }
 
 // Put adds a new layer to the driver.
@@ -651,7 +651,7 @@ func (d *Driver) DiffSize(id, parent string) (size int64, err error) {
 	}
 	defer d.Put(id)
 
-	return archive.ChangesSize(string(layerFs), changes), nil
+	return archive.ChangesSize(layerFs, changes), nil
 }
 
 // GetMetadata returns custom driver information.
diff --git a/daemon/graphdriver/zfs/zfs.go b/daemon/graphdriver/zfs/zfs.go
index aca35e0abd..82f72bf698 100644
--- a/daemon/graphdriver/zfs/zfs.go
+++ b/daemon/graphdriver/zfs/zfs.go
@@ -368,7 +368,7 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, retErr e
 	defer d.locker.Unlock(id)
 	mountpoint := d.mountPath(id)
 	if count := d.ctr.Increment(mountpoint); count > 1 {
-		return containerfs.NewLocalContainerFS(mountpoint), nil
+		return mountpoint, nil
 	}
 	defer func() {
 		if retErr != nil {
@@ -404,7 +404,7 @@ func (d *Driver) Get(id, mountLabel string) (_ containerfs.ContainerFS, retErr e
 		return "", fmt.Errorf("error modifying zfs mountpoint (%s) directory ownership: %v", mountpoint, err)
 	}
 
-	return containerfs.NewLocalContainerFS(mountpoint), nil
+	return mountpoint, nil
 }
 
 // Put removes the existing mountpoint for the given id if it exists.