--- zzzz-none-000/linux-3.10.107/arch/arm64/include/asm/dma-mapping.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arm64/include/asm/dma-mapping.h	2021-02-04 17:41:59.000000000 +0000
@@ -21,58 +21,65 @@
 #include <linux/types.h>
 #include <linux/vmalloc.h>
 
-#include <asm-generic/dma-coherent.h>
+#include <xen/xen.h>
+#include <asm/xen/hypervisor.h>
 
-#define ARCH_HAS_DMA_GET_REQUIRED_MASK
+#define DMA_ERROR_CODE	(~(dma_addr_t)0)
+extern struct dma_map_ops dummy_dma_ops;
 
-extern struct dma_map_ops *dma_ops;
+static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
+{
+	if (dev && dev->archdata.dma_ops)
+		return dev->archdata.dma_ops;
+
+	/*
+	 * We expect no ISA devices, and all other DMA masters are expected to
+	 * have someone call arch_setup_dma_ops at device creation time.
+	 */
+	return &dummy_dma_ops;
+}
 
 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 {
-	if (unlikely(!dev) || !dev->archdata.dma_ops)
-		return dma_ops;
+	if (xen_initial_domain())
+		return xen_dma_ops;
 	else
-		return dev->archdata.dma_ops;
+		return __generic_dma_ops(dev);
 }
 
-#include <asm-generic/dma-mapping-common.h>
+void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+			const struct iommu_ops *iommu, bool coherent);
+#define arch_setup_dma_ops	arch_setup_dma_ops
 
-static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
-{
-	return (dma_addr_t)paddr;
-}
+#ifdef CONFIG_IOMMU_DMA
+void arch_teardown_dma_ops(struct device *dev);
+#define arch_teardown_dma_ops	arch_teardown_dma_ops
+#endif
 
-static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
+/* do not use this function in a driver */
+static inline bool is_device_dma_coherent(struct device *dev)
 {
-	return (phys_addr_t)dev_addr;
+	if (!dev)
+		return false;
+	return dev->archdata.dma_coherent;
 }
 
-static inline int dma_mapping_error(struct device *dev, dma_addr_t dev_addr)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-	debug_dma_mapping_error(dev, dev_addr);
-	return ops->mapping_error(dev, dev_addr);
-}
+#include <asm-generic/dma-mapping-common.h>
 
-static inline int dma_supported(struct device *dev, u64 mask)
+static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
-	struct dma_map_ops *ops = get_dma_ops(dev);
-	return ops->dma_supported(dev, mask);
+	return (dma_addr_t)paddr;
 }
 
-static inline int dma_set_mask(struct device *dev, u64 mask)
+static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
 {
-	if (!dev->dma_mask || !dma_supported(dev, mask))
-		return -EIO;
-	*dev->dma_mask = mask;
-
-	return 0;
+	return (phys_addr_t)dev_addr;
 }
 
 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 {
 	if (!dev->dma_mask)
-		return 0;
+		return false;
 
 	return addr + size - 1 <= *dev->dma_mask;
 }
@@ -81,45 +88,5 @@
 {
 }
 
-static inline void *dma_alloc_coherent(struct device *dev, size_t size,
-				       dma_addr_t *dma_handle, gfp_t flags)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-	void *vaddr;
-
-	if (dma_alloc_from_coherent(dev, size, dma_handle, &vaddr))
-		return vaddr;
-
-	vaddr = ops->alloc(dev, size, dma_handle, flags, NULL);
-	debug_dma_alloc_coherent(dev, size, *dma_handle, vaddr);
-	return vaddr;
-}
-
-static inline void dma_free_coherent(struct device *dev, size_t size,
-				     void *vaddr, dma_addr_t dev_addr)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-
-	if (dma_release_from_coherent(dev, get_order(size), vaddr))
-		return;
-
-	debug_dma_free_coherent(dev, size, vaddr, dev_addr);
-	ops->free(dev, size, vaddr, dev_addr, NULL);
-}
-
-/*
- * There is no dma_cache_sync() implementation, so just return NULL here.
- */
-static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
-					  dma_addr_t *handle, gfp_t flags)
-{
-	return NULL;
-}
-
-static inline void dma_free_noncoherent(struct device *dev, size_t size,
-					void *cpu_addr, dma_addr_t handle)
-{
-}
-
 #endif	/* __KERNEL__ */
 #endif	/* __ASM_DMA_MAPPING_H */