UpperFilter driver question

NTDEV
1

Hi all,

I am writing a disk upper filter driver.
Is there a way to tell if the Microsoft disk class driver is in the stack, some where below my driver?

The reason I am asking this is that I am dealing with some disk virtualization software that has its own disk class driver. In some cases, this driver replaces the Microsoft disk class driver, and I/O have to be sent straight down to the PDO instead of down the stack.

Thanks
Peter T.

2

I don’t think you can have two class drivers for the same device class at
the same time. If you are an upper filter for a device class, then you do
have the class driver below you. And it will always be either MS one or
yours. It is not a good idea to replace MS class driver anyway. You seem to
misunderstand the concept or mix up the terms.

http://www.firestreamer.com - NTBackup to DVD and DV

“Peter Trinh” wrote in message
news:xxxxx@ntdev…
> Hi all,
>
> I am writing a disk upper filter driver.
> Is there a way to tell if the Microsoft disk class driver is in the stack,
> some where below my driver?
>
> The reason I am asking this is that I am dealing with some disk
> virtualization software that has its own disk class driver. In some cases,
> this driver replaces the Microsoft disk class driver, and I/O have to be
> sent straight down to the PDO instead of down the stack.
>
> Thanks
> Peter T.
>
>
>