Re: determining process context

David wrote: 
Hi Don,
 I tried to get the Process context in dispatch routine using
PsGetCurrentProcess and tried to supply this argument to my
PsCreateSystemThread but when I do this, it DOESNT create Thread AT
ALL.
If I change that process handle parameter to (HANDLE)0 , it creates the
thread (which must be in System Context).

So how do I create thread in Current Process context?


Read the docs for PsCreateSystemThread. The handle parameter allows you to create the thread in the process context specified by the handle rather than the default, which is the system process. The other alternative is, as noted earler, to use KeStackAttachProcess.

You have however been warned that there are issues and complications and edge cases and essentially here be dragons. Good luck.


--

=====================
Mark Roddy DDK MVP
Windows 2003/XP/2000 Consulting
Hollis Technology Solutions 603-321-1032
www.hollistech.com


- David

Doron Holan [MS] wrote:

you can create a transaction object and add buffers to it with individual
IOCTL calls.  in the end, you should map the buffers into kernel space in
the dispatch routine and then hand them off to the thread.  getting the
thread back into the process context is not easy, do all the process context
specific actions in your dispatch code.

d

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"David" <know_devig@xxxxxxxxxxx> wrote in message
news:1122099724.982502.35280@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Hi Doron,
     My application requirement is passing multiple buffers to the
kernel so I cannot use buffered or direct method because it will be
locked,
we want to lock the buffers only when device requests it for DMA.
Alternative approach is call-back events but performance wise passing
buffers to kernel will be efficient. Thats why we are using neither
method so we can lock the buffer only when required.




.

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