arch/powerpc/lib/usercopy_64.c

   1 /*
   2  * Functions which are too large to be inlined.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  */
   9 #include <linux/module.h>
  10 #include <linux/uaccess.h>
  11
  12 unsigned long copy_from_user(void *to, const void __user *from, unsigned long n)
  13 {
  14         if (likely(access_ok(VERIFY_READ, from, n)))
  15                 n = __copy_from_user(to, from, n);
  16         else
  17                 memset(to, 0, n);
  18         return n;
  19 }
  20
  21 unsigned long copy_to_user(void __user *to, const void *from, unsigned long n)
  22 {
  23         if (likely(access_ok(VERIFY_WRITE, to, n)))
  24                 n = __copy_to_user(to, from, n);
  25         return n;
  26 }
  27
  28 unsigned long copy_in_user(void __user *to, const void __user *from,
  29                            unsigned long n)
  30 {
  31         might_sleep();
  32         if (likely(access_ok(VERIFY_READ, from, n) &&
  33             access_ok(VERIFY_WRITE, to, n)))
  34                 n =__copy_tofrom_user(to, from, n);
  35         return n;
  36 }
  37
  38 EXPORT_SYMBOL(copy_from_user);
  39 EXPORT_SYMBOL(copy_to_user);
  40 EXPORT_SYMBOL(copy_in_user);
  41