Some architectures, notably ARM, are interested in tweaking this
depending on their runtime DMA addressing limitations.
Acked-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>