xref: /freebsd/sys/compat/linuxkpi/common/include/asm/barrier.h (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 #endif	/* _LINUXKPI_ASM_BARRIER_H_ */
62