Hi Martin, this series fixes scsi and libsas operations on platforms with cache incoherent dma operations. Patch 2 and 3 are originally from Huacai Chen, but I've modified patch two so that it doesn't require his dma_get_cache_alignment() rework, which I'd rather get into the next merge window after the required fixups, and which isn't suitable for a stable backport. Patch 1 is new from me and makes sure dma_get_cache_alignment is always available. As on of the dma-mapping maintainers I'd be happy with it going in through the scsi tree.