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Date: Thu, 17 May 2007 11:46:58 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Stefan Richter <stefanr@s5r6.in-berlin.de>
cc: "Cestonaro, Thilo (external)" 
	<Thilo.Cestonaro.external@fujitsu-siemens.com>,
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Subject: Re: How to guarantee that kmalloc returns an address below 4GB
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On Wed, 16 May 2007, Stefan Richter wrote:

> Cestonaro, Thilo (external) wrote:
> > is there an option for kmalloc, which I can use to allocate
> > a buffer which is in physical memory placed below 4GB?
> > Not in a remapped area.
> 
> GFP_DMA32

Nope. There are no general slabs available for DMA32.

You could use a dma slab by specifying GFP_DMA. However, on i386 and 
x86_64 this will get you memory in the precious first 16MB. On IA64 and 
other platforms you will get memory < 4GB.

Another option is to use the page allocator and specify GFP_DMA32.