1 files changed, 27 insertions, 0 deletions
diff --git a/runtime/graphdriver/devmapper/mount.go b/runtime/graphdriver/devmapper/mount.go
new file mode 100644
index 0000000000..4f19109bf8
--- /dev/null
+++ b/runtime/graphdriver/devmapper/mount.go
@@ -0,0 +1,27 @@
+// +build linux,amd64
+
+package devmapper
+
+import (
+	"path/filepath"
+)
+
+// FIXME: this is copy-pasted from the aufs driver.
+// It should be moved into the core.
+
+var Mounted = func(mountpoint string) (bool, error) {
+	mntpoint, err := osStat(mountpoint)
+	if err != nil {
+		if osIsNotExist(err) {
+			return false, nil
+		}
+		return false, err
+	}
+	parent, err := osStat(filepath.Join(mountpoint, ".."))
+	if err != nil {
+		return false, err
+	}
+	mntpointSt := toSysStatT(mntpoint.Sys())
+	parentSt := toSysStatT(parent.Sys())
+	return mntpointSt.Dev != parentSt.Dev, nil
+}