Fixes cross platform build failure

pkg/volume/local/local.go

@@ -20,7 +20,6 @@ import (
 	"fmt"
 	"github.com/golang/glog"
 	"os"
-	"syscall"
 
 	"k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -233,7 +232,7 @@ func (m *localVolumeMounter) SetUpAt(dir string, fsGroup *int64) error {
 
 		if len(refs) > 0 {
 			fsGroupNew := int64(*fsGroup)
-			fsGroupSame, fsGroupOld, err := isSameFSGroup(m.globalPath, fsGroupNew)
+			fsGroupSame, fsGroupOld, err := volume.IsSameFSGroup(m.globalPath, fsGroupNew)
 			if err != nil {
 				err = fmt.Errorf("failed to check fsGroup for %s (%v)", m.globalPath, err)
 				return err
@@ -293,20 +292,6 @@ func (m *localVolumeMounter) SetUpAt(dir string, fsGroup *int64) error {
 	return nil
 }
 
-// isSameFSGroup is called only for requests to mount an already mounted
-// volume. It checks if fsGroup of new mount request is the same or not.
-// It returns false if it not the same. It also returns current Gid of a path
-// provided for dir variable.
-func isSameFSGroup(dir string, fsGroup int64) (bool, int, error) {
-	info, err := os.Stat(dir)
-	if err != nil {
-		glog.Errorf("Error getting stats for %s (%v)", dir, err)
-		return false, 0, err
-	}
-	s := info.Sys().(*syscall.Stat_t)
-	return int(s.Gid) == int(fsGroup), int(s.Gid), nil
-}
-
 type localVolumeUnmounter struct {
 	*localVolume
 }

pkg/volume/volume_linux.go

@@ -89,3 +89,17 @@ func SetVolumeOwnership(mounter Mounter, fsGroup *int64) error {
 		return nil
 	})
 }
+
+// IsSameFSGroup is called only for requests to mount an already mounted
+// volume. It checks if fsGroup of new mount request is the same or not.
+// It returns false if it not the same. It also returns current Gid of a path
+// provided for dir variable.
+func IsSameFSGroup(dir string, fsGroup int64) (bool, int, error) {
+	info, err := os.Stat(dir)
+	if err != nil {
+		glog.Errorf("Error getting stats for %s (%v)", dir, err)
+		return false, 0, err
+	}
+	s := info.Sys().(*syscall.Stat_t)
+	return int(s.Gid) == int(fsGroup), int(s.Gid), nil
+}

pkg/volume/volume_unsupported.go

@@ -21,3 +21,7 @@ package volume
 func SetVolumeOwnership(mounter Mounter, fsGroup *int64) error {
 	return nil
 }
+
+func IsSameFSGroup(dir string, fsGroup int64) (bool, int, error) {
+	return true, int(fsGroup), nil
+}