[PATCH] x86_64: Use function pointers to call DMA mapping functions
authorMuli Ben-Yehuda <mulix@mulix.org>
Wed, 11 Jan 2006 21:44:42 +0000 (22:44 +0100)
committerLinus Torvalds <torvalds@g5.osdl.org>
Thu, 12 Jan 2006 03:04:55 +0000 (19:04 -0800)
commit17a941d854a3f7b0bb916fdeee4c9ffdcc19d8d3
treeb6b3b55318336adf769bf57141a01a9defbbb202
parent8a6fdd3e912e0ce6f723431d66baf704bf8a1d26
[PATCH] x86_64: Use function pointers to call DMA mapping functions

AK: I hacked Muli's original patch a lot and there were a lot
of changes - all bugs are probably to blame on me now.
There were also some changes in the fall back behaviour
for swiotlb - in particular it doesn't try to use GFP_DMA
now anymore. Also all DMA mapping operations use the
same core dma_alloc_coherent code with proper fallbacks now.
And various other changes and cleanups.

Known problems: iommu=force swiotlb=force together breaks
                needs more testing.

This patch cleans up x86_64's DMA mapping dispatching code. Right now
we have three possible IOMMU types: AGP GART, swiotlb and nommu, and
in the future we will also have Xen's x86_64 swiotlb and other HW
IOMMUs for x86_64. In order to support all of them cleanly, this
patch:

- introduces a struct dma_mapping_ops with function pointers for each
  of the DMA mapping operations of gart (AMD HW IOMMU), swiotlb
  (software IOMMU) and nommu (no IOMMU).

- gets rid of:

  if (swiotlb)
      return swiotlb_xxx();

- PCI_DMA_BUS_IS_PHYS is now checked against the dma_ops being set
This makes swiotlb faster by avoiding double copying in some cases.

Signed-Off-By: Muli Ben-Yehuda <mulix@mulix.org>
Signed-Off-By: Jon D. Mason <jdmason@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
14 files changed:
arch/x86_64/Kconfig
arch/x86_64/kernel/Makefile
arch/x86_64/kernel/pci-dma.c
arch/x86_64/kernel/pci-gart.c
arch/x86_64/kernel/pci-nommu.c
arch/x86_64/kernel/pci-swiotlb.c [new file with mode: 0644]
arch/x86_64/kernel/setup.c
arch/x86_64/mm/init.c
include/asm-x86_64/dma-mapping.h
include/asm-x86_64/gart-mapping.h [new file with mode: 0644]
include/asm-x86_64/pci.h
include/asm-x86_64/proto.h
include/asm-x86_64/swiotlb.h
lib/swiotlb.c