git.samba.org - sfrench/cifs-2.6.git/blob

1 #ifndef _ASM_FUTEX_H

2 #define _ASM_FUTEX_H

4 #ifdef __KERNEL__

6 #include <linux/futex.h>

7 #include <asm/errno.h>

8 #include <asm/uaccess.h>

10 static inline int

11 futex_atomic_op_inuser (int encoded_op, int __user *uaddr)

13 int op = (encoded_op >> 28) & 7;

14 int cmp = (encoded_op >> 24) & 15;

15 int oparg = (encoded_op << 8) >> 20;

16 int cmparg = (encoded_op << 20) >> 20;

17 int oldval = 0, ret;

18 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))

19 oparg = 1 << oparg;

21 if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))

22 return -EFAULT;

24 inc_preempt_count();

26 switch (op) {

27 case FUTEX_OP_SET:

28 case FUTEX_OP_ADD:

29 case FUTEX_OP_OR:

30 case FUTEX_OP_ANDN:

31 case FUTEX_OP_XOR:

32 default:

33 ret = -ENOSYS;

34 }

36 dec_preempt_count();

38 if (!ret) {

39 switch (cmp) {

40 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;

41 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;

42 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;

43 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;

44 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;

45 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;

46 default: ret = -ENOSYS;

47 }

48 }

49 return ret;

52 #endif

53 #endif