v4.19.13 snapshot.
diff --git a/arch/arm/include/asm/dma-iommu.h b/arch/arm/include/asm/dma-iommu.h
new file mode 100644
index 0000000..6821f12
--- /dev/null
+++ b/arch/arm/include/asm/dma-iommu.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASMARM_DMA_IOMMU_H
+#define ASMARM_DMA_IOMMU_H
+
+#ifdef __KERNEL__
+
+#include <linux/mm_types.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-debug.h>
+#include <linux/kref.h>
+
+#define ARM_MAPPING_ERROR (~(dma_addr_t)0x0)
+
+struct dma_iommu_mapping {
+ /* iommu specific data */
+ struct iommu_domain *domain;
+
+ unsigned long **bitmaps; /* array of bitmaps */
+ unsigned int nr_bitmaps; /* nr of elements in array */
+ unsigned int extensions;
+ size_t bitmap_size; /* size of a single bitmap */
+ size_t bits; /* per bitmap */
+ dma_addr_t base;
+
+ spinlock_t lock;
+ struct kref kref;
+};
+
+struct dma_iommu_mapping *
+arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, u64 size);
+
+void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping);
+
+int arm_iommu_attach_device(struct device *dev,
+ struct dma_iommu_mapping *mapping);
+void arm_iommu_detach_device(struct device *dev);
+
+int arm_dma_supported(struct device *dev, u64 mask);
+
+#endif /* __KERNEL__ */
+#endif