Re: [PATCH v2 RFC 7/8] swiotlb-xen: support autotranslate guests

From: David Vrabel
Date: Thu Aug 01 2013 - 08:19:54 EST

On 31/07/13 20:54, Stefano Stabellini wrote:
> Support autotranslate guests in swiotlb-xen by keeping track of the
> phys-to-bus and bus-to-phys mappings of the swiotlb buffer
> (xen_io_tlb_start-xen_io_tlb_end).
> Use a simple direct access on a pre-allocated array for phys-to-bus
> queries. Use a red-black tree for bus-to-phys queries.

It would be nice if the dma_map_page() etc. returned a unique handle in
addition to the dma_addr_t so the lookup on unmap could be cheaper, but
in the absence of this.

Reviewed-by: David Vrabel <david.vrabel@xxxxxxxxxx>

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