GNU Linux-libre 6.9.1-gnu
[releases.git] / tools / virtio / linux / uaccess.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef UACCESS_H
3 #define UACCESS_H
4
5 #include <linux/compiler.h>
6
7 extern void *__user_addr_min, *__user_addr_max;
8
9 #define put_user(x, ptr)                                        \
10 ({                                                              \
11         typeof(ptr) __pu_ptr = (ptr);                           \
12         __chk_user_ptr(__pu_ptr);                               \
13         WRITE_ONCE(*(__pu_ptr), x);                             \
14         0;                                                      \
15 })
16
17 #define get_user(x, ptr)                                        \
18 ({                                                              \
19         typeof(ptr) __pu_ptr = (ptr);                           \
20         __chk_user_ptr(__pu_ptr);                               \
21         x = READ_ONCE(*(__pu_ptr));                             \
22         0;                                                      \
23 })
24
25 static void volatile_memcpy(volatile char *to, const volatile char *from, 
26                             unsigned long n)
27 {
28         while (n--)
29                 *(to++) = *(from++);
30 }
31
32 static inline int copy_from_user(void *to, const void __user volatile *from,
33                                  unsigned long n)
34 {
35         volatile_memcpy(to, from, n);
36         return 0;
37 }
38
39 static inline int copy_to_user(void __user volatile *to, const void *from,
40                                unsigned long n)
41 {
42         volatile_memcpy(to, from, n);
43         return 0;
44 }
45 #endif /* UACCESS_H */