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 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 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 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 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