Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_GENERIC_BITOPS_ATOMIC_H_
3#define _ASM_GENERIC_BITOPS_ATOMIC_H_
4
5#include <linux/atomic.h>
6#include <linux/compiler.h>
7#include <asm/barrier.h>
8
9/*
10 * Implementation of atomic bitops using atomic-fetch ops.
11 * See Documentation/atomic_bitops.txt for details.
12 */
13
14static inline void set_bit(unsigned int nr, volatile unsigned long *p)
15{
16 p += BIT_WORD(nr);
17 atomic_long_or(BIT_MASK(nr), (atomic_long_t *)p);
18}
19
20static inline void clear_bit(unsigned int nr, volatile unsigned long *p)
21{
22 p += BIT_WORD(nr);
23 atomic_long_andnot(BIT_MASK(nr), (atomic_long_t *)p);
24}
25
26static inline void change_bit(unsigned int nr, volatile unsigned long *p)
27{
28 p += BIT_WORD(nr);
29 atomic_long_xor(BIT_MASK(nr), (atomic_long_t *)p);
30}
31
32static inline int test_and_set_bit(unsigned int nr, volatile unsigned long *p)
33{
34 long old;
35 unsigned long mask = BIT_MASK(nr);
36
37 p += BIT_WORD(nr);
38 if (READ_ONCE(*p) & mask)
39 return 1;
40
41 old = atomic_long_fetch_or(mask, (atomic_long_t *)p);
42 return !!(old & mask);
43}
44
45static inline int test_and_clear_bit(unsigned int nr, volatile unsigned long *p)
46{
47 long old;
48 unsigned long mask = BIT_MASK(nr);
49
50 p += BIT_WORD(nr);
51 if (!(READ_ONCE(*p) & mask))
52 return 0;
53
54 old = atomic_long_fetch_andnot(mask, (atomic_long_t *)p);
55 return !!(old & mask);
56}
57
58static inline int test_and_change_bit(unsigned int nr, volatile unsigned long *p)
59{
60 long old;
61 unsigned long mask = BIT_MASK(nr);
62
63 p += BIT_WORD(nr);
64 old = atomic_long_fetch_xor(mask, (atomic_long_t *)p);
65 return !!(old & mask);
66}
67
68#endif /* _ASM_GENERIC_BITOPS_ATOMIC_H */