Blame view

kernel/linux-imx6_3.14.28/tools/virtio/linux/uaccess.h 1.12 KB
6b13f685e   김민수   BSP 최초 추가
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
  #ifndef UACCESS_H
  #define UACCESS_H
  extern void *__user_addr_min, *__user_addr_max;
  
  #define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
  
  static inline void __chk_user_ptr(const volatile void *p, size_t size)
  {
  	assert(p >= __user_addr_min && p + size <= __user_addr_max);
  }
  
  #define put_user(x, ptr)					\
  ({								\
  	typeof(ptr) __pu_ptr = (ptr);				\
  	__chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr));		\
  	ACCESS_ONCE(*(__pu_ptr)) = x;				\
  	0;							\
  })
  
  #define get_user(x, ptr)					\
  ({								\
  	typeof(ptr) __pu_ptr = (ptr);				\
  	__chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr));		\
  	x = ACCESS_ONCE(*(__pu_ptr));				\
  	0;							\
  })
  
  static void volatile_memcpy(volatile char *to, const volatile char *from, 
  			    unsigned long n)
  {
  	while (n--)
  		*(to++) = *(from++);
  }
  
  static inline int copy_from_user(void *to, const void __user volatile *from,
  				 unsigned long n)
  {
  	__chk_user_ptr(from, n);
  	volatile_memcpy(to, from, n);
  	return 0;
  }
  
  static inline int copy_to_user(void __user volatile *to, const void *from,
  			       unsigned long n)
  {
  	__chk_user_ptr(to, n);
  	volatile_memcpy(to, from, n);
  	return 0;
  }
  #endif /* UACCESS_H */