LXR linux/arch/x86/include/asm/uaccess

   1#ifndef _ASM_X86_UACCESS_32_H
   2#define _ASM_X86_UACCESS_32_H
   3
   4/*
   5 * User space memory access functions
   6 */
   7#include <linux/string.h>
   8#include <asm/asm.h>
   9#include <asm/page.h>
  10
  11unsigned long __must_check __copy_user_ll
  12                (void *to, const void *from, unsigned long n);
  13unsigned long __must_check __copy_from_user_ll_nocache_nozero
  14                (void *to, const void __user *from, unsigned long n);
  15
  16static __always_inline unsigned long __must_check
  17raw_copy_to_user(void __user *to, const void *from, unsigned long n)
  18{
  19        return __copy_user_ll((__force void *)to, from, n);
  20}
  21
  22static __always_inline unsigned long
  23raw_copy_from_user(void *to, const void __user *from, unsigned long n)
  24{
  25        if (__builtin_constant_p(n)) {
  26                unsigned long ret;
  27
  28                switch (n) {
  29                case 1:
  30                        ret = 0;
  31                        __uaccess_begin();
  32                        __get_user_asm_nozero(*(u8 *)to, from, ret,
  33                                              "b", "b", "=q", 1);
  34                        __uaccess_end();
  35                        return ret;
  36                case 2:
  37                        ret = 0;
  38                        __uaccess_begin();
  39                        __get_user_asm_nozero(*(u16 *)to, from, ret,
  40                                              "w", "w", "=r", 2);
  41                        __uaccess_end();
  42                        return ret;
  43                case 4:
  44                        ret = 0;
  45                        __uaccess_begin();
  46                        __get_user_asm_nozero(*(u32 *)to, from, ret,
  47                                              "l", "k", "=r", 4);
  48                        __uaccess_end();
  49                        return ret;
  50                }
  51        }
  52        return __copy_user_ll(to, (__force const void *)from, n);
  53}
  54
  55static __always_inline unsigned long
  56__copy_from_user_inatomic_nocache(void *to, const void __user *from,
  57                                  unsigned long n)
  58{
  59       return __copy_from_user_ll_nocache_nozero(to, from, n);
  60}
  61
  62#endif /* _ASM_X86_UACCESS_32_H */
  63