[PATCH] x86-64: dma_ops as const

The dma_ops structure can be const since it never changes
after boot.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>

arch/x86_64/kernel/pci-calgary.c

@@ -507,7 +507,7 @@ error:
 	return ret;
 }
 
-static struct dma_mapping_ops calgary_dma_ops = {
+static const struct dma_mapping_ops calgary_dma_ops = {
 	.alloc_coherent = calgary_alloc_coherent,
 	.map_single = calgary_map_single,
 	.unmap_single = calgary_unmap_single,

arch/x86_64/kernel/pci-gart.c

@@ -556,7 +556,7 @@ static __init int init_k8_gatt(struct agp_kern_info *info)
 
 extern int agp_amd64_init(void);
 
-static struct dma_mapping_ops gart_dma_ops = {
+static const struct dma_mapping_ops gart_dma_ops = {
 	.mapping_error = NULL,
 	.map_single = gart_map_single,
 	.map_simple = gart_map_simple,

arch/x86_64/kernel/pci-nommu.c

@@ -79,7 +79,7 @@ void nommu_unmap_sg(struct device *dev, struct scatterlist *sg,
 {
 }
 
-struct dma_mapping_ops nommu_dma_ops = {
+const struct dma_mapping_ops nommu_dma_ops = {
 	.map_single = nommu_map_single,
 	.unmap_single = nommu_unmap_single,
 	.map_sg = nommu_map_sg,

arch/x86_64/kernel/pci-swiotlb.c

@@ -12,7 +12,7 @@
 int swiotlb __read_mostly;
 EXPORT_SYMBOL(swiotlb);
 
-struct dma_mapping_ops swiotlb_dma_ops = {
+const struct dma_mapping_ops swiotlb_dma_ops = {
 	.mapping_error = swiotlb_dma_mapping_error,
 	.alloc_coherent = swiotlb_alloc_coherent,
 	.free_coherent = swiotlb_free_coherent,

arch/x86_64/mm/init.c

@@ -46,7 +46,7 @@
 #define Dprintk(x...)
 #endif
 
-struct dma_mapping_ops* dma_ops;
+const struct dma_mapping_ops* dma_ops;
 EXPORT_SYMBOL(dma_ops);
 
 static unsigned long dma_reserve __initdata;

include/asm-x86_64/dma-mapping.h

@@ -52,7 +52,7 @@ struct dma_mapping_ops {
 };
 
 extern dma_addr_t bad_dma_address;
-extern struct dma_mapping_ops* dma_ops;
+extern const struct dma_mapping_ops* dma_ops;
 extern int iommu_merge;
 
 static inline int dma_mapping_error(dma_addr_t dma_addr)