1 files changed, 44 insertions, 0 deletions
diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h
new file mode 100644
index 000000000..74be34f3a
--- /dev/null
+++ b/include/linux/iommu-helper.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_IOMMU_HELPER_H
+#define _LINUX_IOMMU_HELPER_H
+
+#include <linux/bug.h>
+#include <linux/log2.h>
+#include <linux/math.h>
+#include <linux/types.h>
+
+static inline unsigned long iommu_device_max_index(unsigned long size,
+						   unsigned long offset,
+						   u64 dma_mask)
+{
+	if (size + offset > dma_mask)
+		return dma_mask - offset + 1;
+	else
+		return size;
+}
+
+static inline int iommu_is_span_boundary(unsigned int index, unsigned int nr,
+		unsigned long shift, unsigned long boundary_size)
+{
+	BUG_ON(!is_power_of_2(boundary_size));
+
+	shift = (shift + index) & (boundary_size - 1);
+	return shift + nr > boundary_size;
+}
+
+extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
+				      unsigned long start, unsigned int nr,
+				      unsigned long shift,
+				      unsigned long boundary_size,
+				      unsigned long align_mask);
+
+static inline unsigned long iommu_num_pages(unsigned long addr,
+					    unsigned long len,
+					    unsigned long io_page_size)
+{
+	unsigned long size = (addr & (io_page_size - 1)) + len;
+
+	return DIV_ROUND_UP(size, io_page_size);
+}
+
+#endif