谁能理解这段话！？？

 In fact, the driver for one stack's PDO is the FDO driver for the next lower branch, as illustrated by the shading in the figure. When the driver receives an IRP in its PDO role, it will do something to perform the IRP, but that might not involve sending the same, or even any other, IRP to the devices in the stack it occupies while performing its FDO role. Conversely, when a bus driver receives an IRP in its FDO role, it might or might not need to send some IRPs to one or more of the devices for which it acts as PDO.
谁能解释翻译一下这段 谢谢！

In fact, the driver for one stack's PDO is the FDO driver for the next lower branch, as illustrated by the shading in the figure. When the driver receives an IRP in its PDO role, it will do something to perform the IRP, but that might not involve sending the same, or even any other, IRP to the devices in the stack it occupies while performing its FDO role. Conversely, when a bus driver receives an IRP in its FDO role, it might or might not need to send some IRPs to one or more of the devices for which it acts as PDO.
谁能解释翻译一下这段 谢谢！

这句话的意思就驱动程序(driver)可能为一个设备栈提供pdo的同时又为另一个设备栈提供fdo,具体可以看看usbstor.sys.
usbstor为usb设备提供fdo,同时也为usbstor总线提供pdo,而此时他的fdo通常由disk.sys提供.

这句话的意思就驱动程序(driver)可能为一个设备栈提供pdo的同时又为另一个设备栈提供fdo,具体可以看看usbstor.sys.
usbstor为usb设备提供fdo,同时也为usbstor总线提供pdo,而此时他的fdo通常由disk.sys提供.

差不多是这样子的