Developer Forum

hello all,
Is it possible for a kernel mode driver to lock down a
buffer area in kernel space, mark the buffer as accessable
from user mode, then pass the kernel virtual address of the
base of this buffer back to the user mode program so the
user mode program can directly access the buffer without
going through the driver.

Yes, but it is difficult to handle all the security and synchronization
issues properly. Try using overlapped device IoCtls first and if
performance is not adequate, look into other options. Don't optimize what
doesn't need optimizing.

--
David J. Craig
Engineer, Sr. Staff Software Systems
Broadcom Corporation

http://www.yqcomputer.com/

It is hard to work with section objects in Windows X64. Anyone successfully
could do that?

--
Sincerely,
Maruf Maniruzzaman,
Software Engineer,
KAZ Software Limited,
Dhaka, Bangladesh.
http://www.yqcomputer.com/
http://www.yqcomputer.com/

Bad idea. It is better for the user app to allocate the buffer, then send
it to the driver which will lock it and map to kernel addresses.

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
XXXX@XXXXX.COM
http://www.yqcomputer.com/

Hello Sir,

thanks for your suggestion. wha i will do please verify it is correct
of not.
1. i allocates the memory allocattion in Driver and pass the address
of that memory allocation to the
application.
2. my question is - i have to map this memory space into the user
space then user will fill this data
what methods i will use in WDM can you
suggest me.