xen/arm: use dev_is_dma_coherent

Use the dma-noncoherent dev_is_dma_coherent helper instead of the home
grown variant.  Note that both are always initialized to the same
value in arch_setup_dma_ops.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Reviewed-by: NStefano Stabellini <sstabellini@kernel.org>

arch/arm/include/asm/dma-mapping.h

@@ -91,12 +91,6 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
 }
 #endif
 
-/* do not use this function in a driver */
-static inline bool is_device_dma_coherent(struct device *dev)
-{
-	return dev->archdata.dma_coherent;
-}
-
 /**
  * arm_dma_alloc - allocate consistent memory for DMA
  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices

arch/arm/xen/mm.c

 // SPDX-License-Identifier: GPL-2.0-only
 #include <linux/cpu.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-noncoherent.h>
 #include <linux/gfp.h>
 #include <linux/highmem.h>
 #include <linux/export.h>
@@ -99,7 +99,7 @@ void __xen_dma_map_page(struct device *hwdev, struct page *page,
 	     dma_addr_t dev_addr, unsigned long offset, size_t size,
 	     enum dma_data_direction dir, unsigned long attrs)
 {
-	if (is_device_dma_coherent(hwdev))
+	if (dev_is_dma_coherent(hwdev))
 		return;
 	if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
 		return;
@@ -112,7 +112,7 @@ void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
 		unsigned long attrs)
 
 {
-	if (is_device_dma_coherent(hwdev))
+	if (dev_is_dma_coherent(hwdev))
 		return;
 	if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
 		return;
@@ -123,7 +123,7 @@ void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
 void __xen_dma_sync_single_for_cpu(struct device *hwdev,
 		dma_addr_t handle, size_t size, enum dma_data_direction dir)
 {
-	if (is_device_dma_coherent(hwdev))
+	if (dev_is_dma_coherent(hwdev))
 		return;
 	__xen_dma_page_dev_to_cpu(hwdev, handle, size, dir);
 }
@@ -131,7 +131,7 @@ void __xen_dma_sync_single_for_cpu(struct device *hwdev,
 void __xen_dma_sync_single_for_device(struct device *hwdev,
 		dma_addr_t handle, size_t size, enum dma_data_direction dir)
 {
-	if (is_device_dma_coherent(hwdev))
+	if (dev_is_dma_coherent(hwdev))
 		return;
 	__xen_dma_page_cpu_to_dev(hwdev, handle, size, dir);
 }
@@ -159,7 +159,7 @@ bool xen_arch_need_swiotlb(struct device *dev,
 	 * memory and we are not able to flush the cache.
 	 */
 	return (!hypercall_cflush && (xen_pfn != bfn) &&
-		!is_device_dma_coherent(dev));
+		!dev_is_dma_coherent(dev));
 }
 
 int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order,

arch/arm64/include/asm/dma-mapping.h

@@ -18,14 +18,5 @@ static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
 	return NULL;
 }
 
-/*
- * Do not use this function in a driver, it is only provided for
- * arch/arm/mm/xen.c, which is used by arm64 as well.
- */
-static inline bool is_device_dma_coherent(struct device *dev)
-{
-	return dev->dma_coherent;
-}
-
 #endif	/* __KERNEL__ */
 #endif	/* __ASM_DMA_MAPPING_H */