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x86: add alloc_coherent dma_ops callback to NOMMU driver 

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Joerg Roedel 2008-08-19 16:32:42 +02:00 committed by Ingo Molnar
parent e4ad68b651
commit c5e835f964
1 changed files with 55 additions and 0 deletions
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55
arch/x86/kernel/pci-nommu.c
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@ -72,7 +72,62 @@ static int nommu_map_sg(struct device *hwdev, struct scatterlist *sg,
return nents;
}
static void *
nommu_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_addr, gfp_t gfp)
{
unsigned long dma_mask;
int node;
struct page *page;
if (hwdev->dma_mask == NULL)
return NULL;
gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
gfp |= __GFP_ZERO;
dma_mask = hwdev->coherent_dma_mask;
if (!dma_mask)
dma_mask = *(hwdev->dma_mask);
if (dma_mask < DMA_24BIT_MASK)
return NULL;
node = dev_to_node(hwdev);
#ifdef CONFIG_X86_64
if (dma_mask <= DMA_32BIT_MASK)
gfp |= GFP_DMA32;
#endif
/* No alloc-free penalty for ISA devices */
if (dma_mask == DMA_24BIT_MASK)
gfp |= GFP_DMA;
again:
page = alloc_pages_node(node, gfp, get_order(size));
if (!page)
return NULL;
if ((page_to_phys(page) + size > dma_mask) && !(gfp & GFP_DMA)) {
free_pages((unsigned long)page_address(page), get_order(size));
gfp |= GFP_DMA;
goto again;
}
*dma_addr = page_to_phys(page);
if (check_addr("alloc_coherent", hwdev, *dma_addr, size)) {
flush_write_buffers();
return page_address(page);
}
free_pages((unsigned long)page_address(page), get_order(size));
return NULL;
}
struct dma_mapping_ops nommu_dma_ops = {
.alloc_coherent = nommu_alloc_coherent,
.map_single = nommu_map_single,
.map_sg = nommu_map_sg,
.is_phys = 1,