On Mon, Jul 23, 2018 at 11:16:10PM +0100, Robin Murphy wrote:

Bonus question: Now that we're collecing DMA API code in kernel/dma/
do we want to reevaluate dma-iommu? On the one hand it's the bulk of a
dma_ops implementation so should perhaps move, but on the other it's
entirely IOMMU-specific code so should perhaps stay where it is... :/

I think drivers/iommu/ is the right place for it.  Higher priorities
would be to actually make it a complete dma_map_ops implementation,
which should be doable by next merge window, and to actually use it
for non-arm(64) iommu drivers..