1 /* Glue code to lib/swiotlb.c */
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>
10 #include <asm/iommu.h>
11 #include <asm/swiotlb.h>
14 int swiotlb __read_mostly;
16 void *swiotlb_alloc_boot(size_t size, unsigned long nslabs)
18 return alloc_bootmem_low_pages(size);
21 void *swiotlb_alloc(unsigned order, unsigned long nslabs)
23 return (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, order);
27 swiotlb_map_single_phys(struct device *hwdev, phys_addr_t paddr, size_t size,
30 return swiotlb_map_single(hwdev, phys_to_virt(paddr), size, direction);
33 static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
34 dma_addr_t *dma_handle, gfp_t flags)
38 vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags);
42 return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
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,
62 void __init pci_swiotlb_init(void)
64 /* don't initialize swiotlb if iommu=off (no_iommu=1) */
65 if (!iommu_detected && !no_iommu && max_pfn > MAX_DMA32_PFN)
70 printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
72 dma_ops = &swiotlb_dma_ops;