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/* Glue code to lib/swiotlb.c */
#include <linux/pci.h>
#include <linux/cache.h>
#include <linux/module.h>
#include <linux/swiotlb.h>
#include <linux/bootmem.h>
#include <linux/dma-mapping.h>
#include <asm/iommu.h>
#include <asm/swiotlb.h>
#include <asm/dma.h>
int swiotlb __read_mostly;
static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flags)
{
void *vaddr;
vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags);
if (vaddr)
return vaddr;
return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
}
static struct dma_map_ops swiotlb_dma_ops = {
.mapping_error = swiotlb_dma_mapping_error,
.alloc_coherent = x86_swiotlb_alloc_coherent,
.free_coherent = swiotlb_free_coherent,
.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
.sync_single_for_device = swiotlb_sync_single_for_device,
.sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu,
.sync_single_range_for_device = swiotlb_sync_single_range_for_device,
.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
.sync_sg_for_device = swiotlb_sync_sg_for_device,
.map_sg = swiotlb_map_sg_attrs,
.unmap_sg = swiotlb_unmap_sg_attrs,
.map_page = swiotlb_map_page,
.unmap_page = swiotlb_unmap_page,
.dma_supported = NULL,
};
/*
* pci_swiotlb_init - initialize swiotlb if necessary
*
* This returns non-zero if we are forced to use swiotlb (by the boot
* option).
*/
int __init pci_swiotlb_init(void)
{
int use_swiotlb = swiotlb | swiotlb_force;
/* don't initialize swiotlb if iommu=off (no_iommu=1) */
#ifdef CONFIG_X86_64
if (!no_iommu && max_pfn > MAX_DMA32_PFN)
swiotlb = 1;
#endif
if (swiotlb_force)
swiotlb = 1;
if (swiotlb) {
swiotlb_init(0);
dma_ops = &swiotlb_dma_ops;
}
return use_swiotlb;
}
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