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() (uaccess_kernel() ? 0 : mfsp(3))
17 #define get_kernel_space() (0)
18
19 /* Returns 0 for success, otherwise, returns number of bytes not transferred. */
20 extern unsigned long pa_memcpy(void *dst, const void *src,
21 unsigned long len);
22
raw_copy_to_user(void __user * dst,const void * src,unsigned long len)23 unsigned long raw_copy_to_user(void __user *dst, const void *src,
24 unsigned long len)
25 {
26 mtsp(get_kernel_space(), 1);
27 mtsp(get_user_space(), 2);
28 return pa_memcpy((void __force *)dst, src, len);
29 }
30 EXPORT_SYMBOL(raw_copy_to_user);
31
raw_copy_from_user(void * dst,const void __user * src,unsigned long len)32 unsigned long raw_copy_from_user(void *dst, const void __user *src,
33 unsigned long len)
34 {
35 mtsp(get_user_space(), 1);
36 mtsp(get_kernel_space(), 2);
37 return pa_memcpy(dst, (void __force *)src, len);
38 }
39 EXPORT_SYMBOL(raw_copy_from_user);
40
memcpy(void * dst,const void * src,size_t count)41 void * memcpy(void * dst,const void *src, size_t count)
42 {
43 mtsp(get_kernel_space(), 1);
44 mtsp(get_kernel_space(), 2);
45 pa_memcpy(dst, src, count);
46 return dst;
47 }
48
49 EXPORT_SYMBOL(memcpy);
50
copy_from_kernel_nofault_allowed(const void * unsafe_src,size_t size)51 bool 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
