Block layer rework for mask allocator This reworks the block layer bouncing to use the mask allocator Instead of using GFP_DMA use device masks derived from the bounce gfp and pass it to the mask allocator. On architectures not converted to the mask allocator the code will transparently fall back to GFP_DMA. Requires the earlier mask allocator patchkit I posted. It is still not 100% finished -- in particular the bouncer still does not know how to use masks > ISA mask, but that is not very difficult to add now. I first wanted to laid the groundwork. One patch ("Convert the blk allocator functions over to the mask allocator") depends on the "blk allocator" in the earlier SCSI DMA rework patchkit I've been posting. That patch can be dropped without trouble if that one is not applied, but if it is applied it is needed. -Andi