设备对象的VPB是什么意思？

当前设备的VPB是什么意思？VPB是指什么？
下面是使用例子：DeviceObject->vbp->DeviceObject
请指教

Storage Volumes
A volume is a storage device, such as a fixed disk, floppy disk, or CD-ROM, that is formatted to store directories and files. A large volume can be divided into more than one logical volume, also called a partition. Each logical volume is formatted for use by a particular media-based file system, such as NTFS, FAT, or CDFS.

A storage volume, or storage device object, is a device object − usually a physical device object (PDO) − that represents a logical volume to the system. The storage device object resides in the storage device stack, but it is not necessarily the topmost device object in the stack.

When a file system is mounted on a storage volume, it creates a file system volume device object (VDO) to represent the volume to the file system. The file system VDO is mounted on the storage device object by means of a shared object called a volume parameter block (VPB).