x86: export pci-nommu's alloc_coherent

[deliverable/linux.git] / arch / x86 / kernel / pci-dma.c

diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 0a1408abcc6244c832eb4801175dcec135cface4..4e612d20170af3451f1b3a901e5d56d60739aaa2 100644 (file)
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -134,6 +134,37 @@ unsigned long iommu_num_pages(unsigned long addr, unsigned long len)
 EXPORT_SYMBOL(iommu_num_pages);
 #endif
 
+void *dma_generic_alloc_coherent(struct device *dev, size_t size,
+                                dma_addr_t *dma_addr, gfp_t flag)
+{
+       unsigned long dma_mask;
+       struct page *page;
+       dma_addr_t addr;
+
+       dma_mask = dma_alloc_coherent_mask(dev, flag);
+
+       flag |= __GFP_ZERO;
+again:
+       page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));
+       if (!page)
+               return NULL;
+
+       addr = page_to_phys(page);
+       if (!is_buffer_dma_capable(dma_mask, addr, size)) {
+               __free_pages(page, get_order(size));
+
+               if (dma_mask < DMA_32BIT_MASK && !(flag & GFP_DMA)) {
+                       flag = (flag & ~GFP_DMA32) | GFP_DMA;
+                       goto again;
+               }
+
+               return NULL;
+       }
+
+       *dma_addr = addr;
+       return page_address(page);
+}
+
 /*
  * See <Documentation/x86_64/boot-options.txt> for the iommu kernel parameter
  * documentation.