xref: /kernel/linux/linux-5.10/arch/sh/include/asm/futex.h (revision 8c2ecf20)
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_SH_FUTEX_H
3#define __ASM_SH_FUTEX_H
4
5#include <linux/futex.h>
6#include <linux/uaccess.h>
7#include <asm/errno.h>
8
9#if !defined(CONFIG_SMP)
10#include <asm/futex-irq.h>
11#elif defined(CONFIG_CPU_J2)
12#include <asm/futex-cas.h>
13#elif defined(CONFIG_CPU_SH4A)
14#include <asm/futex-llsc.h>
15#else
16#error SMP not supported on this configuration.
17#endif
18
19static inline int
20futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
21			      u32 oldval, u32 newval)
22{
23	if (!access_ok(uaddr, sizeof(u32)))
24		return -EFAULT;
25
26	return atomic_futex_op_cmpxchg_inatomic(uval, uaddr, oldval, newval);
27}
28
29static inline int arch_futex_atomic_op_inuser(int op, u32 oparg, int *oval,
30		u32 __user *uaddr)
31{
32	u32 oldval, newval, prev;
33	int ret;
34
35	do {
36		ret = get_user(oldval, uaddr);
37
38		if (ret) break;
39
40		switch (op) {
41		case FUTEX_OP_SET:
42			newval = oparg;
43			break;
44		case FUTEX_OP_ADD:
45			newval = oldval + oparg;
46			break;
47		case FUTEX_OP_OR:
48			newval = oldval | oparg;
49			break;
50		case FUTEX_OP_ANDN:
51			newval = oldval & ~oparg;
52			break;
53		case FUTEX_OP_XOR:
54			newval = oldval ^ oparg;
55			break;
56		default:
57			ret = -ENOSYS;
58			break;
59		}
60
61		if (ret) break;
62
63		ret = futex_atomic_cmpxchg_inatomic(&prev, uaddr, oldval, newval);
64	} while (!ret && prev != oldval);
65
66	if (!ret)
67		*oval = oldval;
68
69	return ret;
70}
71
72#endif /* __ASM_SH_FUTEX_H */
73