52 строки
1.1 KiB
C
52 строки
1.1 KiB
C
#ifndef UACCESS_H
|
|
#define UACCESS_H
|
|
|
|
#include <linux/compiler.h>
|
|
|
|
extern void *__user_addr_min, *__user_addr_max;
|
|
|
|
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)); \
|
|
WRITE_ONCE(*(__pu_ptr), x); \
|
|
0; \
|
|
})
|
|
|
|
#define get_user(x, ptr) \
|
|
({ \
|
|
typeof(ptr) __pu_ptr = (ptr); \
|
|
__chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr)); \
|
|
x = READ_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 */
|