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;
}
