Change return value for ValidateMountMode

1. rename it from ValidateMountMode to ValidMountMode
Because it's a function simply check mount mode is valid or not.
2. remove the rw check return value
It's not supposed to be combined into this function, and we already
have a function for that check.

Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>

daemon/volumes_unix.go

@@ -71,11 +71,10 @@ func parseBindMount(spec string, mountLabel string, config *runconfig.Config) (*
 	case 3:
 		bind.Destination = arr[1]
 		mode := arr[2]
-		isValid, isRw := volume.ValidateMountMode(mode)
-		if !isValid {
+		if !volume.ValidMountMode(mode) {
 			return nil, fmt.Errorf("invalid mode for volumes-from: %s", mode)
 		}
-		bind.RW = isRw
+		bind.RW = volume.ReadWrite(mode)
 		// Mode field is used by SELinux to decide whether to apply label
 		bind.Mode = mode
 	default:
@@ -268,7 +267,7 @@ func parseVolumesFrom(spec string) (string, string, error) {
 
 	if len(specParts) == 2 {
 		mode = specParts[1]
-		if isValid, _ := volume.ValidateMountMode(mode); !isValid {
+		if !volume.ValidMountMode(mode) {
 			return "", "", fmt.Errorf("invalid mode for volumes-from: %s", mode)
 		}
 	}

opts/opts.go

@@ -202,7 +202,7 @@ func validatePath(val string, validateMountMode bool) (string, error) {
 		containerPath = splited[0]
 		val = path.Clean(containerPath)
 	case 2:
-		if isValid, _ := volume.ValidateMountMode(splited[1]); validateMountMode && isValid {
+		if isValid := volume.ValidMountMode(splited[1]); validateMountMode && isValid {
 			containerPath = splited[0]
 			mode = splited[1]
 			val = fmt.Sprintf("%s:%s", path.Clean(containerPath), mode)
@@ -213,7 +213,7 @@ func validatePath(val string, validateMountMode bool) (string, error) {
 	case 3:
 		containerPath = splited[1]
 		mode = splited[2]
-		if isValid, _ := volume.ValidateMountMode(splited[2]); validateMountMode && !isValid {
+		if isValid := volume.ValidMountMode(splited[2]); validateMountMode && !isValid {
 			return val, fmt.Errorf("bad mount mode specified : %s", mode)
 		}
 		val = fmt.Sprintf("%s:%s:%s", splited[0], containerPath, mode)

volume/volume.go

@@ -49,13 +49,13 @@ var roModes = map[string]bool{
 	"Z,ro": true,
 }
 
-// ValidateMountMode will make sure the mount mode is valid.
-// returns if it's a valid mount mode and if it's read-write or not.
-func ValidateMountMode(mode string) (bool, bool) {
-	return roModes[mode] || rwModes[mode], rwModes[mode]
+// ValidMountMode will make sure the mount mode is valid.
+// returns if it's a valid mount mode or not.
+func ValidMountMode(mode string) bool {
+	return roModes[mode] || rwModes[mode]
 }
 
-// ReadWrite tells you if a mode string is a valid read-only mode or not.
+// ReadWrite tells you if a mode string is a valid read-write mode or not.
 func ReadWrite(mode string) bool {
 	return rwModes[mode]
 }