func updateSysfsConfig()

in pkg/csi_mounter/csi_mounter.go [154:189]
28 lines of code
6 McCabe index (conditional complexity)

func updateSysfsConfig(targetMountPath string, sysfsBDI map[string]int64) error {
	// Command will hang until mount completes.
	cmd := exec.Command("mountpoint", "-d", targetMountPath)
	output, err := cmd.CombinedOutput()
	if err != nil {
		klog.Errorf("Error executing mountpoint command on target path %s: %v", targetMountPath, err)
		var exitError *exec.ExitError
		if errors.As(err, &exitError) {
			klog.Errorf("Exit code: %d", exitError.ExitCode())
		}

		return err
	}

	targetDevice := strings.TrimSpace(string(output))
	klog.Infof("Output of mountpoint for target mount path %s: %s", targetMountPath, output)

	for key, value := range sysfsBDI {
		// Update the target value.
		sysfsBDIPath := filepath.Join("/sys/class/bdi/", targetDevice, key)
		file, err := os.OpenFile(sysfsBDIPath, os.O_WRONLY|os.O_TRUNC, 0o644)
		if err != nil {
			return fmt.Errorf("failed to open file %q: %w", sysfsBDIPath, err)
		}
		defer file.Close()

		_, err = file.WriteString(fmt.Sprintf("%d\n", value))
		if err != nil {
			return fmt.Errorf("failed to write to file %q: %w", "echo", err)
		}

		klog.Infof("Updated %s to %d", sysfsBDIPath, value)
	}

	return nil
}