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Date: Fri, 09 Mar 2012 11:23:58 +0100
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Subject: Re: [Qemu-devel] [PATCH 13/13] pseries: Implement IOMMU and DMA for
	PAPR PCI devices
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To: David Gibson <david@gibson.dropbear.id.au>
Cc: agraf@suse.de, mst@redhat.com, eduard.munteanu@linux360.ro, qemu-devel@nongnu.org, rth@twiddle.net

Il 09/03/2012 06:01, David Gibson ha scritto:
> Currently the pseries machine emulation does not support DMA for emulated
> PCI devices, because the PAPR spec always requires a (guest visible,
> paravirtualized) IOMMU which was not implemented.  Now that we have
> infrastructure for IOMMU emulation, we can correct this and allow PCI DMA
> for pseries.
> 
> With the existing PAPR IOMMU code used for VIO devices, this is almost
> trivial. We use a single DMAContext for each (virtual) PCI host bridge,
> which is the usual configuration on real PAPR machines (which often have
> _many_ PCI host bridges).

What about virtio?

Paolo