1 #ifndef _ASM_GENERIC_FUTEX_H
2 #define _ASM_GENERIC_FUTEX_H
3 
4 #include <linux/futex.h>
5 #include <linux/uaccess.h>
6 #include <asm/errno.h>
7 
8 static inline int
futex_atomic_op_inuser(int encoded_op,u32 __user * uaddr)9 futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr)
10 {
11 	int op = (encoded_op >> 28) & 7;
12 	int cmp = (encoded_op >> 24) & 15;
13 	int oparg = (encoded_op << 8) >> 20;
14 	int cmparg = (encoded_op << 20) >> 20;
15 	int oldval = 0, ret;
16 	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
17 		oparg = 1 << oparg;
18 
19 	if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32)))
20 		return -EFAULT;
21 
22 	pagefault_disable();
23 
24 	switch (op) {
25 	case FUTEX_OP_SET:
26 	case FUTEX_OP_ADD:
27 	case FUTEX_OP_OR:
28 	case FUTEX_OP_ANDN:
29 	case FUTEX_OP_XOR:
30 	default:
31 		ret = -ENOSYS;
32 	}
33 
34 	pagefault_enable();
35 
36 	if (!ret) {
37 		switch (cmp) {
38 		case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
39 		case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
40 		case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
41 		case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
42 		case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
43 		case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
44 		default: ret = -ENOSYS;
45 		}
46 	}
47 	return ret;
48 }
49 
50 static inline int
futex_atomic_cmpxchg_inatomic(u32 * uval,u32 __user * uaddr,u32 oldval,u32 newval)51 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
52 			      u32 oldval, u32 newval)
53 {
54 	return -ENOSYS;
55 }
56 
57 #endif
58