android_kernel_samsung_msm8976/tools/virtio/linux/uaccess.h
Rusty Russell 61d0b5a4b2 tools/virtio: separate headers more.
This makes them a bit more like the kernel headers, so we can include more
real kernel headers in our tests.

In addition this means that we don't break tools/virtio with the next
patch.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 14:00:42 +10:30

50 lines
1.1 KiB
C

#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 */