zfs-builds-mm/zfs-0.8.4/include/spl/sys/atomic.h
2020-07-19 16:21:53 +02:00

79 lines
3.3 KiB
C

/*
* Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
* Copyright (C) 2007 The Regents of the University of California.
* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
* Written by Brian Behlendorf <behlendorf1@llnl.gov>.
* UCRL-CODE-235197
*
* This file is part of the SPL, Solaris Porting Layer.
* For details, see <http://zfsonlinux.org/>.
*
* The SPL is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* The SPL is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with the SPL. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _SPL_ATOMIC_H
#define _SPL_ATOMIC_H
#include <linux/module.h>
#include <linux/spinlock.h>
#include <sys/types.h>
/*
* Map the atomic_* functions to the Linux counterparts. This relies on the
* fact that the atomic types are internally really a uint32 or uint64. If
* this were to change an alternate approach would be needed.
*
* N.B. Due to the limitations of the original API atomicity is not strictly
* preserved when using the 64-bit functions on a 32-bit system. In order
* to support this all consumers would need to be updated to use the Linux
* provided atomic_t and atomic64_t types.
*/
#define atomic_inc_32(v) atomic_inc((atomic_t *)(v))
#define atomic_dec_32(v) atomic_dec((atomic_t *)(v))
#define atomic_add_32(v, i) atomic_add((i), (atomic_t *)(v))
#define atomic_sub_32(v, i) atomic_sub((i), (atomic_t *)(v))
#define atomic_inc_32_nv(v) atomic_inc_return((atomic_t *)(v))
#define atomic_dec_32_nv(v) atomic_dec_return((atomic_t *)(v))
#define atomic_add_32_nv(v, i) atomic_add_return((i), (atomic_t *)(v))
#define atomic_sub_32_nv(v, i) atomic_sub_return((i), (atomic_t *)(v))
#define atomic_cas_32(v, x, y) atomic_cmpxchg((atomic_t *)(v), x, y)
#define atomic_swap_32(v, x) atomic_xchg((atomic_t *)(v), x)
#define atomic_inc_64(v) atomic64_inc((atomic64_t *)(v))
#define atomic_dec_64(v) atomic64_dec((atomic64_t *)(v))
#define atomic_add_64(v, i) atomic64_add((i), (atomic64_t *)(v))
#define atomic_sub_64(v, i) atomic64_sub((i), (atomic64_t *)(v))
#define atomic_inc_64_nv(v) atomic64_inc_return((atomic64_t *)(v))
#define atomic_dec_64_nv(v) atomic64_dec_return((atomic64_t *)(v))
#define atomic_add_64_nv(v, i) atomic64_add_return((i), (atomic64_t *)(v))
#define atomic_sub_64_nv(v, i) atomic64_sub_return((i), (atomic64_t *)(v))
#define atomic_cas_64(v, x, y) atomic64_cmpxchg((atomic64_t *)(v), x, y)
#define atomic_swap_64(v, x) atomic64_xchg((atomic64_t *)(v), x)
#ifdef _LP64
static __inline__ void *
atomic_cas_ptr(volatile void *target, void *cmp, void *newval)
{
return ((void *)atomic_cas_64((volatile uint64_t *)target,
(uint64_t)cmp, (uint64_t)newval));
}
#else /* _LP64 */
static __inline__ void *
atomic_cas_ptr(volatile void *target, void *cmp, void *newval)
{
return ((void *)atomic_cas_32((volatile uint32_t *)target,
(uint32_t)cmp, (uint32_t)newval));
}
#endif /* _LP64 */
#endif /* _SPL_ATOMIC_H */