new DMA API conversion for nvme-pci

[Christoph Hellwig]

Hi all,

this series converts the nvme-pci driver to the new IOVA-based DMA API
for the data path.  Note that I've dropped the the Tested-by: and
Reviewed-by: tags from the version Leon sent out with the DMA API as
there's been quite extensive changes.

Diffstat:
 block/bio-integrity.c      |    3 
 block/bio.c                |   20 -
 block/blk-mq-dma.c         |  162 +++++++++++
 drivers/nvme/host/pci.c    |  615 +++++++++++++++++++++++++--------------------
 include/linux/blk-mq-dma.h |   63 ++++
 include/linux/blk_types.h  |    2 
 6 files changed, 596 insertions(+), 269 deletions(-)