1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *    Optimized memory copy routines.
4 *
5 *    Copyright (C) 2004 Randolph Chung <tausq@debian.org>
6 *    Copyright (C) 2013-2017 Helge Deller <deller@gmx.de>
7 *
8 *    Portions derived from the GNU C Library
9 *    Copyright (C) 1991, 1997, 2003 Free Software Foundation, Inc.
10 */
11
12#include <linux/module.h>
13#include <linux/compiler.h>
14#include <linux/uaccess.h>
15
16#define get_user_space()	mfsp(SR_USER)
17#define get_kernel_space()	SR_KERNEL
18
19/* Returns 0 for success, otherwise, returns number of bytes not transferred. */
20extern unsigned long pa_memcpy(void *dst, const void *src,
21				unsigned long len);
22
23unsigned long raw_copy_to_user(void __user *dst, const void *src,
24			       unsigned long len)
25{
26	mtsp(get_kernel_space(), SR_TEMP1);
27	mtsp(get_user_space(), SR_TEMP2);
28	return pa_memcpy((void __force *)dst, src, len);
29}
30EXPORT_SYMBOL(raw_copy_to_user);
31
32unsigned long raw_copy_from_user(void *dst, const void __user *src,
33			       unsigned long len)
34{
35	mtsp(get_user_space(), SR_TEMP1);
36	mtsp(get_kernel_space(), SR_TEMP2);
37	return pa_memcpy(dst, (void __force *)src, len);
38}
39EXPORT_SYMBOL(raw_copy_from_user);
40
41void * memcpy(void * dst,const void *src, size_t count)
42{
43	mtsp(get_kernel_space(), SR_TEMP1);
44	mtsp(get_kernel_space(), SR_TEMP2);
45	pa_memcpy(dst, src, count);
46	return dst;
47}
48
49EXPORT_SYMBOL(memcpy);
50
51bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
52{
53	if ((unsigned long)unsafe_src < PAGE_SIZE)
54		return false;
55	/* check for I/O space F_EXTEND(0xfff00000) access as well? */
56	return true;
57}
58