Commits
Christoph Hellwig committed c9b6180dbf9
swiotlb-xen: use the same foreign page check everywhere xen_dma_map_page uses a different and more complicated check for foreign pages than the other three cache maintainance helpers. Switch it to the simpler pfn_valid method a well, and document the scheme with a single improved comment in xen_dma_map_page. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>