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 <redacted>

David