Merge pull request #4743 from yuchen0cc/main

mount: support checking multiple kinds of block device driver

src/runtime/virtcontainers/container.go

@@ -1319,12 +1319,12 @@ func (c *Container) hotplugDrive(ctx context.Context) error {
 		"mount-point":  dev.mountPoint,
 	}).Info("device details")
 
-	isDM, err := checkStorageDriver(dev.major, dev.minor)
+	isBD, err := checkStorageDriver(dev.major, dev.minor)
 	if err != nil {
 		return err
 	}
 
-	if !isDM {
+	if !isBD {
 		return nil
 	}
 

src/runtime/virtcontainers/mount.go

@@ -194,14 +194,14 @@ func getDeviceForPath(path string) (device, error) {
 	return dev, nil
 }
 
-var blockFormatTemplate = "/sys/dev/block/%d:%d/dm"
+var blockFormatTemplate = "/sys/dev/block/%d:%d/"
 
-var checkStorageDriver = isDeviceMapper
+var checkStorageDriver = isBlockDevice
 
-// isDeviceMapper checks if the device with the major and minor numbers is a devicemapper block device
-func isDeviceMapper(major, minor int) (bool, error) {
+// isBlockDevice checks if the device with the major and minor numbers is a block device
+func isBlockDevice(major, minor int) (bool, error) {
 
-	//Check if /sys/dev/block/${major}-${minor}/dm exists
+	//Check if /sys/dev/block/${major}-${minor}/ exists
 	sysPath := fmt.Sprintf(blockFormatTemplate, major, minor)
 
 	_, err := os.Stat(sysPath)
@@ -209,9 +209,9 @@ func isDeviceMapper(major, minor int) (bool, error) {
 		return true, nil
 	} else if os.IsNotExist(err) {
 		return false, nil
+	} else {
+		return false, err
 	}
-
-	return false, err
 }
 
 const mountPerm = os.FileMode(0755)

src/runtime/virtcontainers/mount_linux_test.go

@@ -305,20 +305,31 @@ func TestGetDeviceForPathValidMount(t *testing.T) {
 	assert.Equal(dev.mountPoint, expected)
 }
 
-func TestIsDeviceMapper(t *testing.T) {
+func TestIsBlockDevice(t *testing.T) {
 	assert := assert.New(t)
 
 	// known major, minor for /dev/tty
 	major := 5
 	minor := 0
 
-	isDM, err := isDeviceMapper(major, minor)
+	isBD, err := isBlockDevice(major, minor)
 	assert.NoError(err)
-	assert.False(isDM)
+	assert.False(isBD)
 
 	// fake the block device format
+	blockFormatTemplateOld := blockFormatTemplate
+	defer func() {
+		blockFormatTemplate = blockFormatTemplateOld
+	}()
+
 	blockFormatTemplate = "/sys/dev/char/%d:%d"
-	isDM, err = isDeviceMapper(major, minor)
+	isBD, err = isBlockDevice(major, minor)
 	assert.NoError(err)
-	assert.True(isDM)
+	assert.True(isBD)
+
+	// invalid template
+	blockFormatTemplate = "\000/sys/dev/char/%d:%d"
+	isBD, err = isBlockDevice(major, minor)
+	assert.Error(err)
+	assert.False(isBD)
 }