fix formatAndMount func issue on Windows

pkg/util/mount/mount_windows.go

@@ -358,10 +358,23 @@ func (mounter *SafeFormatAndMount) formatAndMount(source string, target string,
 	glog.V(4).Infof("Attempting to formatAndMount disk: %s %s %s", fstype, source, target)
 
 	if err := ValidateDiskNumber(source); err != nil {
-		glog.Errorf("azureMount: formatAndMount failed, err: %v\n", err)
+		glog.Errorf("diskMount: formatAndMount failed, err: %v\n", err)
 		return err
 	}
 
+	if len(fstype) == 0 {
+		// Use 'NTFS' as the default
+		fstype = "NTFS"
+	}
+
+	// format disk if it is unformatted(raw)
+	cmd := fmt.Sprintf("Get-Disk -Number %s | Where partitionstyle -eq 'raw' | Initialize-Disk -PartitionStyle MBR -PassThru", source)
+	cmd += fmt.Sprintf(" | New-Partition -AssignDriveLetter -UseMaximumSize | Format-Volume -FileSystem %s -Confirm:$false", fstype)
+	if output, err := mounter.Exec.Run("powershell", "/c", cmd); err != nil {
+		return fmt.Errorf("diskMount: format disk failed, error: %v, output: %q", err, string(output))
+	}
+	glog.V(4).Infof("diskMount: Disk successfully formatted, disk: %q, fstype: %q\n", source, fstype)
+
 	driveLetter, err := getDriveLetterByDiskNumber(source, mounter.Exec)
 	if err != nil {
 		return err