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Re: [Xen-devel] x86 swiotlb questions

To: Keir Fraser <keir@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] x86 swiotlb questions
From: Muli Ben-Yehuda <muli@xxxxxxxxxx>
Date: Tue, 19 Dec 2006 19:07:15 +0200
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Jan Beulich <jbeulich@xxxxxxxxxx>
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On Tue, Dec 19, 2006 at 02:46:41PM +0000, Keir Fraser wrote:
> 
> One thing is we change the value of PCI_BUS_IS_PHYS (or some similar macro
> which I can't quite remember the name of) which I believe turns off some
> bounce-buffer logic contained within the block-device subsystem. So that
> will mean that we get highmem requests hitting the DMA interfaces, where on
> native they would have got filtered earlier by the highmem/lowmem bounce
> buffer logic that is specific to block-device requests.

PCI_DMA_BUS_IS_PHYS, commonly found in asm-$(arch)/pci.h.
 
Cheers,
Muli

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