Hi all, we have a few places where the DMA mapping layer has non-trivial default actions that are questionable and/or dangerous. This series instead wires up the mmap, get_sgtable and get_required_mask methods explicitly and cleans up some surrounding areas. This also means we could get rid of the ARCH_NO_COHERENT_DMA_MMAP kconfig option, as we now require a mmap method wired up, or in case of non-coherent dma-direct the presence of the arch_dma_coherent_to_pfn hook. The only interesting case is that the sound code also checked the ARCH_NO_COHERENT_DMA_MMAP symbol in somewhat odd ways, so I'd like to see a review of the sound situation before going forward with that patch. Changes since v2: - fix use of dma_can_mmap in alsa - improve the CONFIG_* mess a little more Changes since v1: - add a dma_can_mmap helper for alsa