Re: WDF-newbie: Sharing memory between application and driver?

in addition to all of the other suggestions given you to, you must do
thelocking in your EvtIoInCallerContext callback which is guaranteed to be
in the right context. YOur EvtIoDeviceIoControl routine can be called in
any arbitrary context

d

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"Joerg Hoppe" <jhoppe@xxxxxxxxxxxxxxxx> wrote in message
news:OxiLxjuOHHA.4604@xxxxxxxxxxxxxxxxxxxxxxx
I'm porting an old driver from Compuware Driver::Works to WDF.
I need to share memory between application and my driver.

Problem 1:
My application manages larges buffers. The driver should read/write
data to the application buffer directly. No FileRead/FileWrite ... data
access is not sequentiell.

So I pass a buffer pointer to the driver via an IoCtl.
How do I lock/map this buffer so the driver can access it savely?

Problem 2:
My driver allocates kernel memory with ExAllocatePoolWithTag.
The Application issues an IoCtl and wants to receive a pointer to the
memory.
How do I map the result of WdfMemoryGetBuffer to user process space?


Any Wdf-Examples would be helpful.


Thanks


.

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