1 files changed, 49 insertions, 0 deletions
diff --git a/arch/um/include/asm/uaccess.h b/arch/um/include/asm/uaccess.h
new file mode 100644
index 000000000..fe66d659a
--- /dev/null
+++ b/arch/um/include/asm/uaccess.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2015 Richard Weinberger (richard@nod.at)
+ */
+
+#ifndef __UM_UACCESS_H
+#define __UM_UACCESS_H
+
+#include <asm/elf.h>
+
+#define __under_task_size(addr, size) \
+	(((unsigned long) (addr) < TASK_SIZE) && \
+	 (((unsigned long) (addr) + (size)) < TASK_SIZE))
+
+#define __access_ok_vsyscall(addr, size) \
+	  (((unsigned long) (addr) >= FIXADDR_USER_START) && \
+	  ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \
+	  ((unsigned long) (addr) + (size) >= (unsigned long)(addr)))
+
+#define __addr_range_nowrap(addr, size) \
+	((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))
+
+extern unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n);
+extern unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n);
+extern long __strncpy_from_user(char *dst, const char __user *src, long count);
+extern long __strnlen_user(const void __user *str, long len);
+extern unsigned long __clear_user(void __user *mem, unsigned long len);
+static inline int __access_ok(unsigned long addr, unsigned long size);
+
+/* Teach asm-generic/uaccess.h that we have C functions for these. */
+#define __access_ok __access_ok
+#define __clear_user __clear_user
+#define __strnlen_user __strnlen_user
+#define __strncpy_from_user __strncpy_from_user
+#define INLINE_COPY_FROM_USER
+#define INLINE_COPY_TO_USER
+
+#include <asm-generic/uaccess.h>
+
+static inline int __access_ok(unsigned long addr, unsigned long size)
+{
+	return __addr_range_nowrap(addr, size) &&
+		(__under_task_size(addr, size) ||
+		__access_ok_vsyscall(addr, size) ||
+		uaccess_kernel());
+}
+
+#endif