v4.19.13 snapshot.
diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
new file mode 100644
index 0000000..5df2dcc
--- /dev/null
+++ b/arch/riscv/include/asm/mmu.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+
+#ifndef _ASM_RISCV_MMU_H
+#define _ASM_RISCV_MMU_H
+
+#ifndef __ASSEMBLY__
+
+typedef struct {
+	void *vdso;
+#ifdef CONFIG_SMP
+	/* A local icache flush is needed before user execution can resume. */
+	cpumask_t icache_stale_mask;
+#endif
+} mm_context_t;
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_MMU_H */