Merge tag 'dma-mapping-5.8-6' of git://git.infradead.org/users/hch/dma-mapping into master

Pull dma-mapping fixes from Christoph Hellwig:
 "Ensure we always have fully addressable memory in the dma coherent
  pool (Nicolas Saenz Julienne)"

* tag 'dma-mapping-5.8-6' of git://git.infradead.org/users/hch/dma-mapping:
  dma-pool: do not allocate pool memory from CMA
  dma-pool: make sure atomic pool suits device
  dma-pool: introduce dma_guess_pool()
  dma-pool: get rid of dma_in_atomic_pool()
  dma-direct: provide function to check physical memory area validity