@@ -37,7 +37,7 @@ type imageMeta struct {

 }

 type store struct {

-	sync.Mutex

+	sync.RWMutex

 	ls        LayerGetReleaser

 	images    map[ID]*imageMeta

 	fs        StoreBackend

@@ -166,9 +166,6 @@ func (is *store) Create(config []byte) (ID, error) {

 }

 func (is *store) Search(term string) (ID, error) {

-	is.Lock()

-	defer is.Unlock()

-

 	dgst, err := is.digestSet.Lookup(term)

 	if err != nil {

 		if err == digestset.ErrDigestNotFound {

@@ -251,8 +248,8 @@ func (is *store) GetParent(id ID) (ID, error) {

 }

 func (is *store) Children(id ID) []ID {

-	is.Lock()

-	defer is.Unlock()

+	is.RLock()

+	defer is.RUnlock()

 	return is.children(id)

 }

@@ -276,8 +273,8 @@ func (is *store) Map() map[ID]*Image {

 }

 func (is *store) imagesMap(all bool) map[ID]*Image {

-	is.Lock()

-	defer is.Unlock()

+	is.RLock()

+	defer is.RUnlock()

 	images := make(map[ID]*Image)