forked from Minki/linux
17a941d854
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>
43 lines
1.3 KiB
C
43 lines
1.3 KiB
C
/* Glue code to lib/swiotlb.c */
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#include <linux/pci.h>
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#include <linux/cache.h>
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#include <linux/module.h>
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#include <asm/dma-mapping.h>
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#include <asm/proto.h>
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#include <asm/swiotlb.h>
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#include <asm/dma.h>
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int swiotlb __read_mostly;
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EXPORT_SYMBOL(swiotlb);
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struct dma_mapping_ops swiotlb_dma_ops = {
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.mapping_error = swiotlb_dma_mapping_error,
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.alloc_coherent = swiotlb_alloc_coherent,
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.free_coherent = swiotlb_free_coherent,
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.map_single = swiotlb_map_single,
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.unmap_single = swiotlb_unmap_single,
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.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
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.sync_single_for_device = swiotlb_sync_single_for_device,
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.sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu,
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.sync_single_range_for_device = swiotlb_sync_single_range_for_device,
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.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
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.sync_sg_for_device = swiotlb_sync_sg_for_device,
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.map_sg = swiotlb_map_sg,
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.unmap_sg = swiotlb_unmap_sg,
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.dma_supported = NULL,
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};
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void pci_swiotlb_init(void)
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{
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/* don't initialize swiotlb if iommu=off (no_iommu=1) */
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if (!iommu_aperture && !no_iommu &&
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(end_pfn > MAX_DMA32_PFN || force_iommu))
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swiotlb = 1;
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if (swiotlb) {
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swiotlb_init();
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printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
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dma_ops = &swiotlb_dma_ops;
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}
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}
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