1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_GENERIC_FUTEX_H
3 #define _ASM_GENERIC_FUTEX_H
5 #include <linux/futex.h>
6 #include <linux/uaccess.h>
11 * The following implementation only for uniprocessor machines.
12 * It relies on preempt_disable() ensuring mutual exclusion.
17 * arch_futex_atomic_op_inuser() - Atomic arithmetic operation with constant
18 * argument and comparison of the previous
19 * futex value with another constant.
21 * @encoded_op: encoded operation to execute
22 * @uaddr: pointer to user space address
29 arch_futex_atomic_op_inuser(int op, u32 oparg, int *oval, u32 __user *uaddr)
38 if (unlikely(get_user(oldval, uaddr) != 0))
39 goto out_pagefault_enable;
64 if (ret == 0 && unlikely(put_user(tmp, uaddr) != 0))
78 * futex_atomic_cmpxchg_inatomic() - Compare and exchange the content of the
79 * uaddr with newval if the current value is
81 * @uval: pointer to store content of @uaddr
82 * @uaddr: pointer to user space address
84 * @newval: new value to store to @uaddr
91 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
92 u32 oldval, u32 newval)
97 if (unlikely(get_user(val, uaddr) != 0)) {
102 if (val == oldval && unlikely(put_user(newval, uaddr) != 0)) {
115 arch_futex_atomic_op_inuser(int op, u32 oparg, int *oval, u32 __user *uaddr)
140 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
141 u32 oldval, u32 newval)
146 #endif /* CONFIG_SMP */