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
volatile_memcpy(volatile char * to,const volatile char * from,unsigned long n)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
copy_from_user(void * to,const void __user volatile * from,unsigned long n)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
copy_to_user(void __user volatile * to,const void * from,unsigned long n)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 */
46