diff options
Diffstat (limited to 'arch/s390/include/asm/futex.h')
| -rw-r--r-- | arch/s390/include/asm/futex.h | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/s390/include/asm/futex.h b/arch/s390/include/asm/futex.h new file mode 100644 index 00000000000..5c5d02de49e --- /dev/null +++ b/arch/s390/include/asm/futex.h @@ -0,0 +1,52 @@ +#ifndef _ASM_S390_FUTEX_H +#define _ASM_S390_FUTEX_H + +#ifdef __KERNEL__ + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <asm/errno.h> + +static inline int futex_atomic_op_inuser (int encoded_op, int __user *uaddr) +{ + int op = (encoded_op >> 28) & 7; + int cmp = (encoded_op >> 24) & 15; + int oparg = (encoded_op << 8) >> 20; + int cmparg = (encoded_op << 20) >> 20; + int oldval, ret; + + if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) + oparg = 1 << oparg; + + if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int))) + return -EFAULT; + + pagefault_disable(); + ret = uaccess.futex_atomic_op(op, uaddr, oparg, &oldval); + pagefault_enable(); + + if (!ret) { + switch (cmp) { + case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break; + case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break; + case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break; + case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break; + case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break; + case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break; + default: ret = -ENOSYS; + } + } + return ret; +} + +static inline int futex_atomic_cmpxchg_inatomic(int __user *uaddr, + int oldval, int newval) +{ + if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int))) + return -EFAULT; + + return uaccess.futex_atomic_cmpxchg(uaddr, oldval, newval); +} + +#endif /* __KERNEL__ */ +#endif /* _ASM_S390_FUTEX_H */ |