1/*-
2 * Copyright (c) 2020 The FreeBSD Foundation
3 *
4 * This software was developed by Emmanuel Vadot under sponsorship
5 * from the FreeBSD Foundation.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following 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 AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD$
29 */
30
31#ifndef _LINUX_REFCOUNT_H
32#define _LINUX_REFCOUNT_H
33
34#include <linux/atomic.h>
35
36struct refcount_linux {
37	atomic_t value;
38};
39typedef struct refcount_linux refcount_t;
40
41static inline void
42refcount_set(refcount_t *ref, unsigned int i)
43{
44	atomic_set(&ref->value, i);
45}
46
47static inline void
48refcount_inc(refcount_t *ref)
49{
50	atomic_inc(&ref->value);
51}
52
53static inline bool
54refcount_inc_not_zero(refcount_t *ref)
55{
56	return (atomic_inc_not_zero(&ref->value));
57}
58
59static inline void
60refcount_dec(refcount_t *ref)
61{
62	atomic_dec(&ref->value);
63}
64
65static inline unsigned int
66refcount_read(refcount_t *ref)
67{
68	return atomic_read(&ref->value);
69}
70
71static inline bool
72refcount_dec_and_lock_irqsave(refcount_t *ref, spinlock_t *lock,
73    unsigned long *flags)
74{
75	if (atomic_dec_and_test(&ref->value) == true) {
76		spin_lock_irqsave(lock, flags);
77		return (true);
78	}
79	return (false);
80}
81
82#endif /* __LINUX_REFCOUNT_H__ */
83