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 #include <linux/mm.h> 16 17 #define get_user_space() mfsp(SR_USER) 18 #define get_kernel_space() SR_KERNEL 19 20 /* Returns 0 for success, otherwise, returns number of bytes not transferred. */ 21 extern unsigned long pa_memcpy(void *dst, const void *src, 22 unsigned long len); 23 24 unsigned long raw_copy_to_user(void __user *dst, const void *src, 25 unsigned long len) 26 { 27 mtsp(get_kernel_space(), SR_TEMP1); 28 mtsp(get_user_space(), SR_TEMP2); 29 return pa_memcpy((void __force *)dst, src, len); 30 } 31 EXPORT_SYMBOL(raw_copy_to_user); 32 33 unsigned long raw_copy_from_user(void *dst, const void __user *src, 34 unsigned long len) 35 { 36 unsigned long start = (unsigned long) src; 37 unsigned long end = start + len; 38 unsigned long newlen = len; 39 40 mtsp(get_user_space(), SR_TEMP1); 41 mtsp(get_kernel_space(), SR_TEMP2); 42 43 /* Check region is user accessible */ 44 if (start) 45 while (start < end) { 46 if (!prober_user(SR_TEMP1, start)) { 47 newlen = (start - (unsigned long) src); 48 break; 49 } 50 start += PAGE_SIZE; 51 /* align to page boundry which may have different permission */ 52 start = PAGE_ALIGN_DOWN(start); 53 } 54 return len - newlen + pa_memcpy(dst, (void __force *)src, newlen); 55 } 56 EXPORT_SYMBOL(raw_copy_from_user); 57 58 void * memcpy(void * dst,const void *src, size_t count) 59 { 60 mtsp(get_kernel_space(), SR_TEMP1); 61 mtsp(get_kernel_space(), SR_TEMP2); 62 pa_memcpy(dst, src, count); 63 return dst; 64 } 65 66 EXPORT_SYMBOL(memcpy); 67 68 bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size) 69 { 70 if ((unsigned long)unsafe_src < PAGE_SIZE) 71 return false; 72 /* check for I/O space F_EXTEND(0xfff00000) access as well? */ 73 return true; 74 } 75