From mboxrd@z Thu Jan  1 00:00:00 1970
From: Muli Ben-Yehuda <muli@il.ibm.com>
Subject: Re: x86 swiotlb questions
Date: Tue, 19 Dec 2006 19:07:15 +0200
Message-ID: <20061219170715.GF4240@rhun.ibm.com>
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	<C1ADABD1.6540%keir@xensource.com>
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To: Keir Fraser <keir@xensource.com>
Cc: xen-devel@lists.xensource.com, Jan Beulich <jbeulich@novell.com>
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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