arch/s390/include/asm/futex.h

   1 #ifndef _ASM_S390_FUTEX_H
   2 #define _ASM_S390_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 {
  10         int op = (encoded_op >> 28) & 7;
  11         int cmp = (encoded_op >> 24) & 15;
  12         int oparg = (encoded_op << 8) >> 20;
  13         int cmparg = (encoded_op << 20) >> 20;
  14         int oldval, ret;
  15
  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         ret = uaccess.futex_atomic_op(op, uaddr, oparg, &oldval);
  24         pagefault_enable();
  25
  26         if (!ret) {
  27                 switch (cmp) {
  28                 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
  29                 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
  30                 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
  31                 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
  32                 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
  33                 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
  34                 default: ret = -ENOSYS;
  35                 }
  36         }
  37         return ret;
  38 }
  39
  40 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  41                                                 u32 oldval, u32 newval)
  42 {
  43         if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32)))
  44                 return -EFAULT;
  45
  46         return uaccess.futex_atomic_cmpxchg(uval, uaddr, oldval, newval);
  47 }
  48
  49 #endif /* _ASM_S390_FUTEX_H */