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      1 #ifndef _ASM_GENERIC_FUTEX_H
      2 #define _ASM_GENERIC_FUTEX_H
      3 
      4 #ifdef __KERNEL__
      5 
      6 #include <linux/futex.h>
      7 #include <asm/errno.h>
      8 #include <asm/uaccess.h>
      9 
     10 static inline int
     11 futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
     12 {
     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;
     20 
     21 	if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
     22 		return -EFAULT;
     23 
     24 	inc_preempt_count();
     25 
     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 	}
     35 
     36 	dec_preempt_count();
     37 
     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;
     50 }
     51 
     52 static inline int
     53 futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
     54 {
     55 	return -ENOSYS;
     56 }
     57 
     58 #endif
     59 #endif
     60