SAFE public projects git trees. - safe/jmp/linux-2.6/blob - arch/x86/kernel/pci-swiotlb_64.c

   1 /* Glue code to lib/swiotlb.c */
   2
   3 #include <linux/pci.h>
   4 #include <linux/cache.h>
   5 #include <linux/module.h>
   6 #include <linux/swiotlb.h>
   7 #include <linux/bootmem.h>
   8 #include <linux/dma-mapping.h>
   9
  10 #include <asm/iommu.h>
  11 #include <asm/swiotlb.h>
  12 #include <asm/dma.h>
  13
  14 int swiotlb __read_mostly;
  15
  16 void *swiotlb_alloc_boot(size_t size, unsigned long nslabs)
  17 {
  18         return alloc_bootmem_low_pages(size);
  19 }
  20
  21 void *swiotlb_alloc(unsigned order, unsigned long nslabs)
  22 {
  23         return (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, order);
  24 }
  25
  26 static dma_addr_t
  27 swiotlb_map_single_phys(struct device *hwdev, phys_addr_t paddr, size_t size,
  28                         int direction)
  29 {
  30         return swiotlb_map_single(hwdev, phys_to_virt(paddr), size, direction);
  31 }
  32
  33 static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
  34                                         dma_addr_t *dma_handle, gfp_t flags)
  35 {
  36         void *vaddr;
  37
  38         vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags);
  39         if (vaddr)
  40                 return vaddr;
  41
  42         return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
  43 }
  44
  45 struct dma_mapping_ops swiotlb_dma_ops = {
  46         .mapping_error = swiotlb_dma_mapping_error,
  47         .alloc_coherent = x86_swiotlb_alloc_coherent,
  48         .free_coherent = swiotlb_free_coherent,
  49         .map_single = swiotlb_map_single_phys,
  50         .unmap_single = swiotlb_unmap_single,
  51         .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
  52         .sync_single_for_device = swiotlb_sync_single_for_device,
  53         .sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu,
  54         .sync_single_range_for_device = swiotlb_sync_single_range_for_device,
  55         .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
  56         .sync_sg_for_device = swiotlb_sync_sg_for_device,
  57         .map_sg = swiotlb_map_sg,
  58         .unmap_sg = swiotlb_unmap_sg,
  59         .dma_supported = NULL,
  60 };
  61
  62 void __init pci_swiotlb_init(void)
  63 {
  64         /* don't initialize swiotlb if iommu=off (no_iommu=1) */
  65         if (!iommu_detected && !no_iommu && max_pfn > MAX_DMA32_PFN)
  66                swiotlb = 1;
  67         if (swiotlb_force)
  68                 swiotlb = 1;
  69         if (swiotlb) {
  70                 printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
  71                 swiotlb_init();
  72                 dma_ops = &swiotlb_dma_ops;
  73         }
  74 }