LXR linux/arch/powerpc/lib/usercopy

   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 <asm/uaccess.h>
  11
  12unsigned 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
  21unsigned 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
  28unsigned 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
  38EXPORT_SYMBOL(copy_from_user);
  39EXPORT_SYMBOL(copy_to_user);
  40EXPORT_SYMBOL(copy_in_user);
  41
  42