@@ -38,7 +38,6 @@ type MetaData struct {

 type DeviceSet struct {

 	MetaData

 	sync.Mutex

-	initialized      bool

 	root             string

 	devicePrefix     string

 	TransactionId    uint64

@@ -450,11 +449,6 @@ func (devices *DeviceSet) AddDevice(hash, baseHash string) error {

 	devices.Lock()

 	defer devices.Unlock()

-	if err := devices.ensureInit(); err != nil {

-		utils.Debugf("Error init: %s\n", err)

-		return err

-	}

-

 	if devices.Devices[hash] != nil {

 		return fmt.Errorf("hash %s already exists", hash)

 	}

@@ -522,11 +516,6 @@ func (devices *DeviceSet) RemoveDevice(hash string) error {

 	devices.Lock()

 	defer devices.Unlock()

-	if err := devices.ensureInit(); err != nil {

-		utils.Debugf("\n--->Err: %s\n", err)

-		return err

-	}

-

 	return devices.removeDevice(hash)

 }

@@ -635,10 +624,6 @@ func (devices *DeviceSet) Shutdown() error {

 	utils.Debugf("[devmapper] Shutting down DeviceSet: %s", devices.root)

 	defer devices.Unlock()

-	if !devices.initialized {

-		return nil

-	}

-

 	for path, count := range devices.activeMounts {

 		for i := count; i > 0; i-- {

 			if err := syscall.Unmount(path, 0); err != nil {

@@ -671,10 +656,6 @@ func (devices *DeviceSet) MountDevice(hash, path string, readOnly bool) error {

 	devices.Lock()

 	defer devices.Unlock()

-	if err := devices.ensureInit(); err != nil {

-		return fmt.Errorf("Error initializing devmapper: %s", err)

-	}

-

 	if err := devices.activateDeviceIfNeeded(hash); err != nil {

 		return fmt.Errorf("Error activating devmapper device for '%s': %s", hash, err)

 	}

@@ -736,9 +717,6 @@ func (devices *DeviceSet) HasDevice(hash string) bool {

 	devices.Lock()

 	defer devices.Unlock()

-	if err := devices.ensureInit(); err != nil {

-		return false

-	}

 	return devices.Devices[hash] != nil

 }

@@ -746,10 +724,6 @@ func (devices *DeviceSet) HasInitializedDevice(hash string) bool {

 	devices.Lock()

 	defer devices.Unlock()

-	if err := devices.ensureInit(); err != nil {

-		return false

-	}

-

 	info := devices.Devices[hash]

 	return info != nil && info.Initialized

 }

@@ -758,10 +732,6 @@ func (devices *DeviceSet) HasActivatedDevice(hash string) bool {

 	devices.Lock()

 	defer devices.Unlock()

-	if err := devices.ensureInit(); err != nil {

-		return false

-	}

-

 	info := devices.Devices[hash]

 	if info == nil {

 		return false

@@ -774,11 +744,6 @@ func (devices *DeviceSet) SetInitialized(hash string) error {

 	devices.Lock()

 	defer devices.Unlock()

-	if err := devices.ensureInit(); err != nil {

-		utils.Debugf("\n--->Err: %s\n", err)

-		return err

-	}

-

 	info := devices.Devices[hash]

 	if info == nil {

 		return fmt.Errorf("Unknown device %s", hash)

@@ -800,10 +765,6 @@ func (devices *DeviceSet) Status() *Status {

 	status := &Status{}

-	if err := devices.ensureInit(); err != nil {

-		return status

-	}

-

 	status.PoolName = devices.getPoolName()

 	status.DataLoopback = path.Join(devices.loopbackDir(), "data")

 	status.MetadataLoopback = path.Join(devices.loopbackDir(), "metadata")

@@ -827,24 +788,18 @@ func (devices *DeviceSet) Status() *Status {

 	return status

 }

-func (devices *DeviceSet) ensureInit() error {

-	if !devices.initialized {

-		devices.initialized = true

-		if err := devices.initDevmapper(); err != nil {

-			utils.Debugf("\n--->Err: %s\n", err)

-			return err

-		}

-	}

-	return nil

-}

-

-func NewDeviceSet(root string) *DeviceSet {

+func NewDeviceSet(root string) (*DeviceSet, error) {

 	SetDevDir("/dev")

-	return &DeviceSet{

-		initialized:  false,

+	devices := &DeviceSet{

 		root:         root,

 		MetaData:     MetaData{Devices: make(map[string]*DevInfo)},

 		activeMounts: make(map[string]int),

 	}

+

+	if err := devices.initDevmapper(); err != nil {

+		return nil, err

+	}

+

+	return devices, nil

 }

@@ -22,13 +22,14 @@ type Driver struct {

 }

 func Init(home string) (graphdriver.Driver, error) {

+	deviceSet, err := NewDeviceSet(home);

+	if err != nil {

+		return nil, err

+	}

 	d := &Driver{

-		DeviceSet: NewDeviceSet(home),

+		DeviceSet: deviceSet,

 		home:      home,

 	}

-	if err := d.DeviceSet.ensureInit(); err != nil {

-		return nil, err

-	}

 	return d, nil

 }