@@ -7,7 +7,7 @@ import (

 	"github.com/Sirupsen/logrus"

 	derr "github.com/docker/docker/errors"

-	"github.com/docker/docker/volume/store"

+	volumestore "github.com/docker/docker/volume/store"

 )

 // ContainerRmConfig is a holder for passing in runtime config.

@@ -153,7 +153,7 @@ func (daemon *Daemon) VolumeRm(name string) error {

 		return err

 	}

 	if err := daemon.volumes.Remove(v); err != nil {

-		if err == store.ErrVolumeInUse {

+		if volumestore.IsInUse(err) {

 			return derr.ErrorCodeRmVolumeInUse.WithArgs(err)

 		}

 		return derr.ErrorCodeRmVolume.WithArgs(name, err)

@@ -4,7 +4,7 @@ import (

 	"strings"

 	derr "github.com/docker/docker/errors"

-	"github.com/docker/docker/volume/store"

+	volumestore "github.com/docker/docker/volume/store"

 )

 func (daemon *Daemon) prepareMountPoints(container *Container) error {

@@ -34,7 +34,7 @@ func (daemon *Daemon) removeMountPoints(container *Container, rm bool) error {

 			// not an error, but an implementation detail.

 			// This prevents docker from logging "ERROR: Volume in use"

 			// where there is another container using the volume.

-			if err != nil && err != store.ErrVolumeInUse {

+			if err != nil && !volumestore.IsInUse(err) {

 				rmErrors = append(rmErrors, err.Error())

 			}

 		}

new file mode 100644

@@ -0,0 +1,58 @@

+package store

+

+import "errors"

+

+var (

+	// errVolumeInUse is a typed error returned when trying to remove a volume that is currently in use by a container

+	errVolumeInUse = errors.New("volume is in use")

+	// errNoSuchVolume is a typed error returned if the requested volume doesn't exist in the volume store

+	errNoSuchVolume = errors.New("no such volume")

+	// errInvalidName is a typed error returned when creating a volume with a name that is not valid on the platform

+	errInvalidName = errors.New("volume name is not valid on this platform")

+)

+

+// OpErr is the error type returned by functions in the store package. It describes

+// the operation, volume name, and error.

+type OpErr struct {

+	// Err is the error that occurred during the operation.

+	Err error

+	// Op is the operation which caused the error, such as "create", or "list".

+	Op string

+	// Name is the name of the resource being requested for this op, typically the volume name or the driver name.

+	Name string

+}

+

+// Error satifies the built-in error interface type.

+func (e *OpErr) Error() string {

+	if e == nil {

+		return "<nil>"

+	}

+	s := e.Op

+	if e.Name != "" {

+		s = s + " " + e.Name

+	}

+

+	s = s + ": " + e.Err.Error()

+	return s

+}

+

+// IsInUse returns a boolean indicating whether the error indicates that a

+// volume is in use

+func IsInUse(err error) bool {

+	return isErr(err, errVolumeInUse)

+}

+

+// IsNotExist returns a boolean indicating whether the error indicates that the volume does not exist

+func IsNotExist(err error) bool {

+	return isErr(err, errNoSuchVolume)

+}

+

+func isErr(err error, expected error) bool {

+	switch pe := err.(type) {

+	case nil:

+		return false

+	case *OpErr:

+		err = pe.Err

+	}

+	return err == expected

+}

@@ -1,7 +1,6 @@

 package store

 import (

-	"errors"

 	"sync"

 	"github.com/Sirupsen/logrus"

@@ -10,15 +9,6 @@ import (

 	"github.com/docker/docker/volume/drivers"

 )

-var (

-	// ErrVolumeInUse is a typed error returned when trying to remove a volume that is currently in use by a container

-	ErrVolumeInUse = errors.New("volume is in use")

-	// ErrNoSuchVolume is a typed error returned if the requested volume doesn't exist in the volume store

-	ErrNoSuchVolume = errors.New("no such volume")

-	// ErrInvalidName is a typed error returned when creating a volume with a name that is not valid on the platform

-	ErrInvalidName = errors.New("volume name is not valid on this platform")

-)

-

 // New initializes a VolumeStore to keep

 // reference counting of volumes in the system.

 func New() *VolumeStore {

@@ -81,7 +71,7 @@ func (s *VolumeStore) Create(name, driverName string, opts map[string]string) (v

 	vd, err := volumedrivers.GetDriver(driverName)

 	if err != nil {

-		return nil, err

+		return nil, &OpErr{Err: err, Name: driverName, Op: "create"}

 	}

 	// Validate the name in a platform-specific manner

@@ -90,12 +80,12 @@ func (s *VolumeStore) Create(name, driverName string, opts map[string]string) (v

 		return nil, err

 	}

 	if !valid {

-		return nil, ErrInvalidName

+		return nil, &OpErr{Err: errInvalidName, Name: name, Op: "create"}

 	}

 	v, err := vd.Create(name, opts)

 	if err != nil {

-		return nil, err

+		return nil, &OpErr{Op: "create", Name: name, Err: err}

 	}

 	s.set(name, &volumeCounter{v, 0})

@@ -110,7 +100,7 @@ func (s *VolumeStore) Get(name string) (volume.Volume, error) {

 	vc, exists := s.get(name)

 	if !exists {

-		return nil, ErrNoSuchVolume

+		return nil, &OpErr{Err: errNoSuchVolume, Name: name, Op: "get"}

 	}

 	return vc.Volume, nil

 }

@@ -124,19 +114,19 @@ func (s *VolumeStore) Remove(v volume.Volume) error {

 	logrus.Debugf("Removing volume reference: driver %s, name %s", v.DriverName(), name)

 	vc, exists := s.get(name)

 	if !exists {

-		return ErrNoSuchVolume

+		return &OpErr{Err: errNoSuchVolume, Name: name, Op: "remove"}

 	}

 	if vc.count > 0 {

-		return ErrVolumeInUse

+		return &OpErr{Err: errVolumeInUse, Name: name, Op: "remove"}

 	}

 	vd, err := volumedrivers.GetDriver(vc.DriverName())

 	if err != nil {

-		return err

+		return &OpErr{Err: err, Name: vc.DriverName(), Op: "remove"}

 	}

 	if err := vd.Remove(vc.Volume); err != nil {

-		return err

+		return &OpErr{Err: err, Name: name, Op: "remove"}

 	}

 	s.remove(name)

@@ -1,6 +1,7 @@

 package store

 import (

+	"errors"

 	"testing"

 	"github.com/docker/docker/volume"

@@ -30,8 +31,8 @@ func TestGet(t *testing.T) {

 		t.Fatalf("Expected fake1 volume, got %v", v)

 	}

-	if _, err := s.Get("fake4"); err != ErrNoSuchVolume {

-		t.Fatalf("Expected ErrNoSuchVolume error, got %v", err)

+	if _, err := s.Get("fake4"); !IsNotExist(err) {

+		t.Fatalf("Expected IsNotExist error, got %v", err)

 	}

 }

@@ -54,24 +55,25 @@ func TestCreate(t *testing.T) {

 	}

 	_, err = s.Create("fakeError", "fake", map[string]string{"error": "create error"})

-	if err == nil || err.Error() != "create error" {

-		t.Fatalf("Expected create error, got %v", err)

+	expected := &OpErr{Op: "create", Name: "fakeError", Err: errors.New("create error")}

+	if err != nil && err.Error() != expected.Error() {

+		t.Fatalf("Expected create fakeError: create error, got %v", err)

 	}

 }

 func TestRemove(t *testing.T) {

 	volumedrivers.Register(vt.FakeDriver{}, "fake")

 	s := New()

-	if err := s.Remove(vt.NoopVolume{}); err != ErrNoSuchVolume {

-		t.Fatalf("Expected ErrNoSuchVolume error, got %v", err)

+	if err := s.Remove(vt.NoopVolume{}); !IsNotExist(err) {

+		t.Fatalf("Expected IsNotExist error, got %v", err)

 	}

 	v, err := s.Create("fake1", "fake", nil)

 	if err != nil {

 		t.Fatal(err)

 	}

 	s.Increment(v)

-	if err := s.Remove(v); err != ErrVolumeInUse {

-		t.Fatalf("Expected ErrVolumeInUse error, got %v", err)

+	if err := s.Remove(v); !IsInUse(err) {

+		t.Fatalf("Expected IsInUse error, got %v", err)

 	}

 	s.Decrement(v)

 	if err := s.Remove(v); err != nil {