forked from Minki/linux
03967c5267
This restores the old swiotlb alloc_coherent behavior (before the alloc_coherent rewrite): http://lkml.org/lkml/2008/8/12/200 The old alloc_coherent avoids GFP_DMA allocation first and if the allocated address is not fit for the device's coherent_dma_mask, then dma_alloc_coherent does GFP_DMA allocation. If it fails, alloc_coherent calls swiotlb_alloc_coherent (in short, we rarely used swiotlb_alloc_coherent). After the alloc_coherent rewrite, dma_alloc_coherent (include/asm-x86/dma-mapping.h) directly calls swiotlb_alloc_coherent. It means that we possibly can't handle a device having dma_masks > 24bit < 32bits since swiotlb_alloc_coherent doesn't have the above GFP_DMA retry mechanism. This patch fixes x86's swiotlb alloc_coherent to use the GFP_DMA retry mechanism, which dma_generic_alloc_coherent() provides now (pci-nommu.c and GART IOMMU driver also use dma_generic_alloc_coherent). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Ingo Molnar <mingo@elte.hu>
63 lines
1.7 KiB
C
63 lines
1.7 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 <linux/dma-mapping.h>
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#include <asm/iommu.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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static dma_addr_t
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swiotlb_map_single_phys(struct device *hwdev, phys_addr_t paddr, size_t size,
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int direction)
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{
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return swiotlb_map_single(hwdev, phys_to_virt(paddr), size, direction);
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}
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static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
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dma_addr_t *dma_handle, gfp_t flags)
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{
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void *vaddr;
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vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags);
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if (vaddr)
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return vaddr;
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return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
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}
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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 = x86_swiotlb_alloc_coherent,
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.free_coherent = swiotlb_free_coherent,
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.map_single = swiotlb_map_single_phys,
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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 __init 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_detected && !no_iommu && max_pfn > MAX_DMA32_PFN)
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swiotlb = 1;
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if (swiotlb_force)
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swiotlb = 1;
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if (swiotlb) {
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printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
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swiotlb_init();
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dma_ops = &swiotlb_dma_ops;
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}
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}
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