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Allocating memory in a device driver

ern31
ern31 asked
on
Medium Priority
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Last Modified: 2013-12-03
I need to allocate memory in a device driver (atapi).
Somebody tell me ExAllocatePool is wrong in a DD isn't it?
So I am trying to use MmAllocateNonCachedMemory.
The problem is that the compiler says it can't found the
function... and if I include "ntddk.h" it founds a lot
of re-declarations... so I can't obtain the memory
and the driver is sttoped.

Can someone help me?
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Commented:
Are you including the correct library/.LIB file for MmAllocateNonCachedMemory?

Author

Commented:
MmAllocateNonCachedMemory is in ntddk.h as far as I know.
If I include it it doesn't link (repeated simbols)... if
I do it links (assuming extern declaration returning int) but
the drives hungs.
Thanks.

Commented:
I would suggest you to use ExAllocatePool().  It should be fine.  You can even use NdisAllocateMemory() to allocate non-paged memory.  The problem with redeclaration is probably caused by the order of the include files.  Try have "ntddk.h" as the first header file.
-----from DDK-----
Each call to MmAllocateNonCachedMemory ties up at least a full page of nonpaged system-space memory, whatever the size of the requested allocation. For requests less than a page, any remainder bytes on the page are wasted: inaccessible by the driver that called MmAllocateNonCachedMemory and unusable by other kernel-mode code.

Commented:
How do you compile the driver? Hope you know you should use BUILD utility.
What kind of driver is it (custom, network, printer, ...)?

Author

Commented:
I have decide it is not posible to allocate dinamic memory in
a device driver (atapi). I compile the driver without any error,
with BUILD of course, but if I use ExAllocate the system crash
(IRQ_LEVEL_NOT_EQUAL...): this is ok (reading DDK it says ExAllocate don't go on device drivers) but if I use MmAllocate
the system crash too (¿?) KERNEL_MODE_EXCEPTION_NOT_HANDLE.
Well there are *NOT* other system calls to allocate memory so
I have decided IT'S NOT POSIBLE IN A D.DRIVER.
Anyway thaks for your help.
Commented:
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