From 17a941d854a3f7b0bb916fdeee4c9ffdcc19d8d3 Mon Sep 17 00:00:00 2001 From: Muli Ben-Yehuda Date: Wed, 11 Jan 2006 22:44:42 +0100 Subject: [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 Signed-Off-By: Jon D. Mason Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- include/asm-x86_64/pci.h | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'include/asm-x86_64/pci.h') diff --git a/include/asm-x86_64/pci.h b/include/asm-x86_64/pci.h index eeb3088a1c9e..fd03e15d7ea6 100644 --- a/include/asm-x86_64/pci.h +++ b/include/asm-x86_64/pci.h @@ -42,18 +42,20 @@ int pcibios_set_irq_routing(struct pci_dev *dev, int pin, int irq); #include #include #include +#include /* for have_iommu */ extern int iommu_setup(char *opt); -#ifdef CONFIG_GART_IOMMU /* The PCI address space does equal the physical memory * address space. The networking and block device layers use * this boolean for bounce buffer decisions * - * On AMD64 it mostly equals, but we set it to zero to tell some subsystems - * that an IOMMU is available. + * On AMD64 it mostly equals, but we set it to zero if a hardware + * IOMMU (gart) of sotware IOMMU (swiotlb) is available. */ -#define PCI_DMA_BUS_IS_PHYS (no_iommu ? 1 : 0) +#define PCI_DMA_BUS_IS_PHYS (dma_ops->is_phys) + +#ifdef CONFIG_GART_IOMMU /* * x86-64 always supports DAC, but sometimes it is useful to force @@ -79,7 +81,6 @@ extern int iommu_sac_force; #else /* No IOMMU */ -#define PCI_DMA_BUS_IS_PHYS 1 #define pci_dac_dma_supported(pci_dev, mask) 1 #define DECLARE_PCI_UNMAP_ADDR(ADDR_NAME) -- cgit v1.2.3