1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2021 Vladimir Kondratyev <wulf@FreeBSD.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice unmodified, this list of conditions, and the following
11 *    disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#ifndef _LINUXKPI_ASM_BARRIER_H_
29#define	_LINUXKPI_ASM_BARRIER_H_
30
31#include <sys/types.h>
32#include <machine/atomic.h>
33
34#include <asm/atomic.h>
35#include <linux/compiler.h>
36
37/* TODO: Check other archs for atomic_thread_fence_* useability */
38#if defined(__amd64__) || defined(__i386__)
39#define	smp_mb()	atomic_thread_fence_seq_cst()
40#define	smp_wmb()	atomic_thread_fence_rel()
41#define	smp_rmb()	atomic_thread_fence_acq()
42#define	smp_store_mb(x, v)	do { (void)xchg(&(x), v); } while (0)
43#endif
44
45#ifndef	smp_mb
46#define	smp_mb()	mb()
47#endif
48#ifndef	smp_wmb
49#define	smp_wmb()	wmb()
50#endif
51#ifndef	smp_rmb
52#define	smp_rmb()	rmb()
53#endif
54#ifndef	smp_store_mb
55#define	smp_store_mb(x, v)	do { WRITE_ONCE(x, v); smp_mb(); } while (0)
56#endif
57
58#define	smp_mb__before_atomic()	barrier()
59#define	smp_mb__after_atomic()	barrier()
60
61#define smp_store_release(p, v)	do { smp_mb(); WRITE_ONCE(*p, v); } while (0)
62#define smp_load_acquire(p) ({ typeof(*p) _v = READ_ONCE(*p); smp_mb(); _v; })
63
64#endif	/* _LINUXKPI_ASM_BARRIER_H_ */
65