kernel/arch/m68k/lib/uaccess.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file COPYING in the main directory of this archive
   4  * for more details.
   5  */
   6
   7 #include <linux/module.h>
   8 #include <asm/uaccess.h>
   9
  10 unsigned long __generic_copy_from_user(void *to, const void __user *from,
  11                                        unsigned long n)
  12 {
  13         unsigned long tmp, res;
  14
  15         asm volatile ("\n"
  16                 "       tst.l   %0\n"
  17                 "       jeq     2f\n"
  18                 "1:     "MOVES".l       (%1)+,%3\n"
  19                 "       move.l  %3,(%2)+\n"
  20                 "       subq.l  #1,%0\n"
  21                 "       jne     1b\n"
  22                 "2:     btst    #1,%5\n"
  23                 "       jeq     4f\n"
  24                 "3:     "MOVES".w       (%1)+,%3\n"
  25                 "       move.w  %3,(%2)+\n"
  26                 "4:     btst    #0,%5\n"
  27                 "       jeq     6f\n"
  28                 "5:     "MOVES".b       (%1)+,%3\n"
  29                 "       move.b  %3,(%2)+\n"
  30                 "6:\n"
  31                 "       .section .fixup,\"ax\"\n"
  32                 "       .even\n"
  33                 "10:    move.l  %0,%3\n"
  34                 "7:     clr.l   (%2)+\n"
  35                 "       subq.l  #1,%3\n"
  36                 "       jne     7b\n"
  37                 "       lsl.l   #2,%0\n"
  38                 "       btst    #1,%5\n"
  39                 "       jeq     8f\n"
  40                 "30:    clr.w   (%2)+\n"
  41                 "       addq.l  #2,%0\n"
  42                 "8:     btst    #0,%5\n"
  43                 "       jeq     6b\n"
  44                 "50:    clr.b   (%2)+\n"
  45                 "       addq.l  #1,%0\n"
  46                 "       jra     6b\n"
  47                 "       .previous\n"
  48                 "\n"
  49                 "       .section __ex_table,\"a\"\n"
  50                 "       .align  4\n"
  51                 "       .long   1b,10b\n"
  52                 "       .long   3b,30b\n"
  53                 "       .long   5b,50b\n"
  54                 "       .previous"
  55                 : "=d" (res), "+a" (from), "+a" (to), "=&d" (tmp)
  56                 : "0" (n / 4), "d" (n & 3));
  57
  58         return res;
  59 }
  60 EXPORT_SYMBOL(__generic_copy_from_user);
  61
  62 unsigned long __generic_copy_to_user(void __user *to, const void *from,
  63                                      unsigned long n)
  64 {
  65         unsigned long tmp, res;
  66
  67         asm volatile ("\n"
  68                 "       tst.l   %0\n"
  69                 "       jeq     4f\n"
  70                 "1:     move.l  (%1)+,%3\n"
  71                 "2:     "MOVES".l       %3,(%2)+\n"
  72                 "3:     subq.l  #1,%0\n"
  73                 "       jne     1b\n"
  74                 "4:     btst    #1,%5\n"
  75                 "       jeq     6f\n"
  76                 "       move.w  (%1)+,%3\n"
  77                 "5:     "MOVES".w       %3,(%2)+\n"
  78                 "6:     btst    #0,%5\n"
  79                 "       jeq     8f\n"
  80                 "       move.b  (%1)+,%3\n"
  81                 "7:     "MOVES".b  %3,(%2)+\n"
  82                 "8:\n"
  83                 "       .section .fixup,\"ax\"\n"
  84                 "       .even\n"
  85                 "20:    lsl.l   #2,%0\n"
  86                 "50:    add.l   %5,%0\n"
  87                 "       jra     8b\n"
  88                 "       .previous\n"
  89                 "\n"
  90                 "       .section __ex_table,\"a\"\n"
  91                 "       .align  4\n"
  92                 "       .long   2b,20b\n"
  93                 "       .long   3b,20b\n"
  94                 "       .long   5b,50b\n"
  95                 "       .long   6b,50b\n"
  96                 "       .long   7b,50b\n"
  97                 "       .long   8b,50b\n"
  98                 "       .previous"
  99                 : "=d" (res), "+a" (from), "+a" (to), "=&d" (tmp)
 100                 : "0" (n / 4), "d" (n & 3));
 101
 102         return res;
 103 }
 104 EXPORT_SYMBOL(__generic_copy_to_user);
 105
 106 /*
 107  * Zero Userspace
 108  */
 109
 110 unsigned long __clear_user(void __user *to, unsigned long n)
 111 {
 112         unsigned long res;
 113
 114         asm volatile ("\n"
 115                 "       tst.l   %0\n"
 116                 "       jeq     3f\n"
 117                 "1:     "MOVES".l       %2,(%1)+\n"
 118                 "2:     subq.l  #1,%0\n"
 119                 "       jne     1b\n"
 120                 "3:     btst    #1,%4\n"
 121                 "       jeq     5f\n"
 122                 "4:     "MOVES".w       %2,(%1)+\n"
 123                 "5:     btst    #0,%4\n"
 124                 "       jeq     7f\n"
 125                 "6:     "MOVES".b       %2,(%1)\n"
 126                 "7:\n"
 127                 "       .section .fixup,\"ax\"\n"
 128                 "       .even\n"
 129                 "10:    lsl.l   #2,%0\n"
 130                 "40:    add.l   %4,%0\n"
 131                 "       jra     7b\n"
 132                 "       .previous\n"
 133                 "\n"
 134                 "       .section __ex_table,\"a\"\n"
 135                 "       .align  4\n"
 136                 "       .long   1b,10b\n"
 137                 "       .long   2b,10b\n"
 138                 "       .long   4b,40b\n"
 139                 "       .long   5b,40b\n"
 140                 "       .long   6b,40b\n"
 141                 "       .long   7b,40b\n"
 142                 "       .previous"
 143                 : "=d" (res), "+a" (to)
 144                 : "d" (0), "0" (n / 4), "d" (n & 3));
 145
 146     return res;
 147 }
 148 EXPORT_SYMBOL(__clear_user);