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 static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
17 dma_addr_t *dma_handle, gfp_t flags)
21 vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags);
25 return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
28 static struct dma_map_ops swiotlb_dma_ops = {
29 .mapping_error = swiotlb_dma_mapping_error,
30 .alloc_coherent = x86_swiotlb_alloc_coherent,
31 .free_coherent = swiotlb_free_coherent,
32 .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
33 .sync_single_for_device = swiotlb_sync_single_for_device,
34 .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
35 .sync_sg_for_device = swiotlb_sync_sg_for_device,
36 .map_sg = swiotlb_map_sg_attrs,
37 .unmap_sg = swiotlb_unmap_sg_attrs,
38 .map_page = swiotlb_map_page,
39 .unmap_page = swiotlb_unmap_page,
40 .dma_supported = NULL,
44 * pci_swiotlb_detect - set swiotlb to 1 if necessary
46 * This returns non-zero if we are forced to use swiotlb (by the boot
49 int __init pci_swiotlb_detect(void)
51 int use_swiotlb = swiotlb | swiotlb_force;
53 /* don't initialize swiotlb if iommu=off (no_iommu=1) */
55 if (!no_iommu && max_pfn > MAX_DMA32_PFN)
64 void __init pci_swiotlb_init(void)
68 dma_ops = &swiotlb_dma_ops;