RFC arm64: IOMMU-backed DMA mapping

Hi all,

Whilst it's a long way off perfect, this has reached the point of being functional and stable enough to be useful, so here it is. The core consists of the meat of the arch/arm implementation modified to remove the assumption of PAGE_SIZE pages and ported over to the Intel IOVA allocator instead of the bitmap-based one. For that, this series depends on my "Genericise the IOVA allocator" series posted earlier[1].

There are plenty of obvious things still to do, including:

* Domain and group handling is all wrong, but that's a bigger problem. For the moment it does more or less the same thing as the arch/arm code, which at least works for the one-IOMMU-per-device situation.
* IOMMU domains and IOVA domains probably want to be better integrated with devices and each other, rather than having a proliferation of arch-specific structs.
* The temporary map_sg implementation - I have a 'proper' iommu_map_sg based one in progress, but since the simple one works it's not been as high a priority.
* Port arch/arm over to it. I'd guess it might be preferable to merge this through arm64 first, though, rather than overcomplicate matters.
* There may well be scope for streamlining and tidying up the copied parts - In general I've simply avoided touching anything I don't fully understand.
* In the same vein, I'm sure lots of it is fairly ARM-specific, so will need longer-term work to become truly generic.

[1]:http://thread.gmane.org/gmane.linux.kernel.iommu/8208

Catalin Marinas (1):
arm64: Combine coherent and non-coherent swiotlb dma_ops

Robin Murphy (4):
arm64: implement generic IOMMU configuration
iommu: implement common IOMMU ops for DMA mapping
arm64: add IOMMU dma_ops
arm64: hook up IOMMU dma_ops

 arch/arm64/Kconfig                   |   1 +
 arch/arm64/include/asm/device.h      |   3 +
 arch/arm64/include/asm/dma-mapping.h |  33 +--
 arch/arm64/kernel/setup.c            |   2 +
 arch/arm64/mm/dma-mapping.c          | 435 ++++++++++++++++++++++++++++-----
 include/linux/dma-iommu.h            |  78 ++++++
 lib/Kconfig                          |   8 +
 lib/Makefile                         |   1 +
 lib/dma-iommu.c                      | 455 +++++++++++++++++++++++++++++++++++
 9 files changed, 938 insertions(+), 78 deletions(-)
 create mode 100644 include/linux/dma-iommu.h
 create mode 100644 lib/dma-iommu.c

1.9.1