x86: export pci-nommu's alloc_coherent

This patch exports nommu_alloc_coherent (renamed
dma_generic_alloc_coherent). GART needs this function.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 35 insertions, 38 deletions

diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 0a1408abcc62..4e612d20170a 100644
--- 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.
diff --git a/arch/x86/kernel/pci-nommu.c b/arch/x86/kernel/pci-nommu.c
index 1c1c98a31d57..c70ab5a5d4c8 100644
--- a/arch/x86/kernel/pci-nommu.c
+++ b/arch/x86/kernel/pci-nommu.c
@@ -72,43 +72,6 @@ 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;
-        dma_addr_t addr;
-
-        dma_mask = dma_alloc_coherent_mask(hwdev, gfp);
-
-        gfp |= __GFP_ZERO;
-
-        node = dev_to_node(hwdev);
-again:
-        page = alloc_pages_node(node, gfp, get_order(size));
-        if (!page)
-                return NULL;
-
-        addr = page_to_phys(page);
-        if (!is_buffer_dma_capable(dma_mask, addr, size) && !(gfp & GFP_DMA)) {
-                free_pages((unsigned long)page_address(page), get_order(size));
-                gfp |= GFP_DMA;
-                goto again;
-        }
-
-        if (check_addr("alloc_coherent", hwdev, addr, size)) {
-                *dma_addr = addr;
-                flush_write_buffers();
-                return page_address(page);
-        }
-
-        free_pages((unsigned long)page_address(page), get_order(size));
-
-        return NULL;
-}
-
 static void nommu_free_coherent(struct device *dev, size_t size, void *vaddr,
                                 dma_addr_t dma_addr)
 {
@@ -116,7 +79,7 @@ static void nommu_free_coherent(struct device *dev, size_t size, void *vaddr,
 }
 
 struct dma_mapping_ops nommu_dma_ops = {
-        .alloc_coherent = nommu_alloc_coherent,
+        .alloc_coherent = dma_generic_alloc_coherent,
         .free_coherent = nommu_free_coherent,
         .map_single = nommu_map_single,
         .map_sg = nommu_map_sg,
diff --git a/include/asm-x86/dma-mapping.h b/include/asm-x86/dma-mapping.h
index f408e6dd1778..3b808e9bb72c 100644
--- a/include/asm-x86/dma-mapping.h
+++ b/include/asm-x86/dma-mapping.h
@@ -89,6 +89,9 @@ static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 extern int dma_supported(struct device *hwdev, u64 mask);
 extern int dma_set_mask(struct device *dev, u64 mask);
 
+extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
+                                        dma_addr_t *dma_addr, gfp_t flag);
+
 static inline dma_addr_t
 dma_map_single(struct device *hwdev, void *ptr, size_t size,
                int direction)