void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { void *ret, *ret_nocache; int order = get_order(size); gfp |= __GFP_ZERO; ret = (void *)__get_free_pages(gfp, order); if (!ret) return NULL; /* * Pages from the page allocator may have data present in * cache. So flush the cache before using uncached memory. */ arch_sync_dma_for_device(dev, virt_to_phys(ret), size, DMA_BIDIRECTIONAL); ret_nocache = (void __force *)ioremap_nocache(virt_to_phys(ret), size); if (!ret_nocache) { free_pages((unsigned long)ret, order); return NULL; } split_page(pfn_to_page(virt_to_phys(ret) >> PAGE_SHIFT), order); *dma_handle = virt_to_phys(ret); if (!WARN_ON(!dev)) *dma_handle -= PFN_PHYS(dev->dma_pfn_offset); return ret_nocache; }
void dma_direct_sync_single_for_device(struct device *dev, dma_addr_t addr, size_t size, enum dma_data_direction dir) { phys_addr_t paddr = dma_to_phys(dev, addr); if (unlikely(is_swiotlb_buffer(paddr))) swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_DEVICE); if (!dev_is_dma_coherent(dev)) arch_sync_dma_for_device(dev, paddr, size, dir); }
void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir) { struct scatterlist *sg; int i; for_each_sg(sgl, sg, nents, i) { if (unlikely(is_swiotlb_buffer(sg_phys(sg)))) swiotlb_tbl_sync_single(dev, sg_phys(sg), sg->length, dir, SYNC_FOR_DEVICE); if (!dev_is_dma_coherent(dev)) arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir); } }
dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, unsigned long attrs) { phys_addr_t phys = page_to_phys(page) + offset; dma_addr_t dma_addr = phys_to_dma(dev, phys); if (unlikely(!dma_direct_possible(dev, dma_addr, size)) && !swiotlb_map(dev, &phys, &dma_addr, size, dir, attrs)) { report_addr(dev, dma_addr, size); return DMA_MAPPING_ERROR; } if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) arch_sync_dma_for_device(dev, phys, size, dir); return dma_addr; }