arch/parisc/lib/memcpy.c

   1 /*
   2  *    Optimized memory copy routines.
   3  *
   4  *    Copyright (C) 2004 Randolph Chung <tausq@debian.org>
   5  *    Copyright (C) 2013-2017 Helge Deller <deller@gmx.de>
   6  *
   7  *    This program is free software; you can redistribute it and/or modify
   8  *    it under the terms of the GNU General Public License as published by
   9  *    the Free Software Foundation; either version 2, or (at your option)
  10  *    any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program; if not, write to the Free Software
  19  *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  *    Portions derived from the GNU C Library
  22  *    Copyright (C) 1991, 1997, 2003 Free Software Foundation, Inc.
  23  *
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/compiler.h>
  28 #include <linux/uaccess.h>
  29
  30 DECLARE_PER_CPU(struct exception_data, exception_data);
  31
  32 #define get_user_space() (uaccess_kernel() ? 0 : mfsp(3))
  33 #define get_kernel_space() (0)
  34
  35 /* Returns 0 for success, otherwise, returns number of bytes not transferred. */
  36 extern unsigned long pa_memcpy(void *dst, const void *src,
  37                                 unsigned long len);
  38
  39 unsigned long __copy_to_user(void __user *dst, const void *src,
  40                              unsigned long len)
  41 {
  42         mtsp(get_kernel_space(), 1);
  43         mtsp(get_user_space(), 2);
  44         return pa_memcpy((void __force *)dst, src, len);
  45 }
  46 EXPORT_SYMBOL(__copy_to_user);
  47
  48 unsigned long __copy_from_user(void *dst, const void __user *src,
  49                                unsigned long len)
  50 {
  51         mtsp(get_user_space(), 1);
  52         mtsp(get_kernel_space(), 2);
  53         return pa_memcpy(dst, (void __force *)src, len);
  54 }
  55 EXPORT_SYMBOL(__copy_from_user);
  56
  57 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len)
  58 {
  59         mtsp(get_user_space(), 1);
  60         mtsp(get_user_space(), 2);
  61         return pa_memcpy((void __force *)dst, (void __force *)src, len);
  62 }
  63
  64
  65 void * memcpy(void * dst,const void *src, size_t count)
  66 {
  67         mtsp(get_kernel_space(), 1);
  68         mtsp(get_kernel_space(), 2);
  69         pa_memcpy(dst, src, count);
  70         return dst;
  71 }
  72
  73 EXPORT_SYMBOL(copy_in_user);
  74 EXPORT_SYMBOL(memcpy);
  75
  76 long probe_kernel_read(void *dst, const void *src, size_t size)
  77 {
  78         unsigned long addr = (unsigned long)src;
  79
  80         if (addr < PAGE_SIZE)
  81                 return -EFAULT;
  82
  83         /* check for I/O space F_EXTEND(0xfff00000) access as well? */
  84
  85         return __probe_kernel_read(dst, src, size);
  86 }