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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_GENERIC_BITOPS_NON_ATOMIC_H_
3#define _ASM_GENERIC_BITOPS_NON_ATOMIC_H_
4
5#include <asm/types.h>
6
7/**
8 * __set_bit - Set a bit in memory
9 * @nr: the bit to set
10 * @addr: the address to start counting from
11 *
12 * Unlike set_bit(), this function is non-atomic and may be reordered.
13 * If it's called on the same region of memory simultaneously, the effect
14 * may be that only one operation succeeds.
15 */
16static inline void __set_bit(int nr, volatile unsigned long *addr)
17{
18 unsigned long mask = BIT_MASK(nr);
19 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
20
21 *p |= mask;
22}
23
24static inline void __clear_bit(int nr, volatile unsigned long *addr)
25{
26 unsigned long mask = BIT_MASK(nr);
27 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
28
29 *p &= ~mask;
30}
31
32/**
33 * __change_bit - Toggle a bit in memory
34 * @nr: the bit to change
35 * @addr: the address to start counting from
36 *
37 * Unlike change_bit(), this function is non-atomic and may be reordered.
38 * If it's called on the same region of memory simultaneously, the effect
39 * may be that only one operation succeeds.
40 */
41static inline void __change_bit(int nr, volatile unsigned long *addr)
42{
43 unsigned long mask = BIT_MASK(nr);
44 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
45
46 *p ^= mask;
47}
48
49/**
50 * __test_and_set_bit - Set a bit and return its old value
51 * @nr: Bit to set
52 * @addr: Address to count from
53 *
54 * This operation is non-atomic and can be reordered.
55 * If two examples of this operation race, one can appear to succeed
56 * but actually fail. You must protect multiple accesses with a lock.
57 */
58static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
59{
60 unsigned long mask = BIT_MASK(nr);
61 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
62 unsigned long old = *p;
63
64 *p = old | mask;
65 return (old & mask) != 0;
66}
67
68/**
69 * __test_and_clear_bit - Clear a bit and return its old value
70 * @nr: Bit to clear
71 * @addr: Address to count from
72 *
73 * This operation is non-atomic and can be reordered.
74 * If two examples of this operation race, one can appear to succeed
75 * but actually fail. You must protect multiple accesses with a lock.
76 */
77static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
78{
79 unsigned long mask = BIT_MASK(nr);
80 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
81 unsigned long old = *p;
82
83 *p = old & ~mask;
84 return (old & mask) != 0;
85}
86
87/* WARNING: non atomic and it can be reordered! */
88static inline int __test_and_change_bit(int nr,
89 volatile unsigned long *addr)
90{
91 unsigned long mask = BIT_MASK(nr);
92 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
93 unsigned long old = *p;
94
95 *p = old ^ mask;
96 return (old & mask) != 0;
97}
98
99/**
100 * test_bit - Determine whether a bit is set
101 * @nr: bit number to test
102 * @addr: Address to start counting from
103 */
104static inline int test_bit(int nr, const volatile unsigned long *addr)
105{
106 return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
107}
108
109#endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */
1#ifndef _ASM_GENERIC_BITOPS_NON_ATOMIC_H_
2#define _ASM_GENERIC_BITOPS_NON_ATOMIC_H_
3
4#include <asm/types.h>
5
6/**
7 * __set_bit - Set a bit in memory
8 * @nr: the bit to set
9 * @addr: the address to start counting from
10 *
11 * Unlike set_bit(), this function is non-atomic and may be reordered.
12 * If it's called on the same region of memory simultaneously, the effect
13 * may be that only one operation succeeds.
14 */
15static inline void __set_bit(int nr, volatile unsigned long *addr)
16{
17 unsigned long mask = BIT_MASK(nr);
18 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
19
20 *p |= mask;
21}
22
23static inline void __clear_bit(int nr, volatile unsigned long *addr)
24{
25 unsigned long mask = BIT_MASK(nr);
26 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
27
28 *p &= ~mask;
29}
30
31/**
32 * __change_bit - Toggle a bit in memory
33 * @nr: the bit to change
34 * @addr: the address to start counting from
35 *
36 * Unlike change_bit(), this function is non-atomic and may be reordered.
37 * If it's called on the same region of memory simultaneously, the effect
38 * may be that only one operation succeeds.
39 */
40static inline void __change_bit(int nr, volatile unsigned long *addr)
41{
42 unsigned long mask = BIT_MASK(nr);
43 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
44
45 *p ^= mask;
46}
47
48/**
49 * __test_and_set_bit - Set a bit and return its old value
50 * @nr: Bit to set
51 * @addr: Address to count from
52 *
53 * This operation is non-atomic and can be reordered.
54 * If two examples of this operation race, one can appear to succeed
55 * but actually fail. You must protect multiple accesses with a lock.
56 */
57static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
58{
59 unsigned long mask = BIT_MASK(nr);
60 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
61 unsigned long old = *p;
62
63 *p = old | mask;
64 return (old & mask) != 0;
65}
66
67/**
68 * __test_and_clear_bit - Clear a bit and return its old value
69 * @nr: Bit to clear
70 * @addr: Address to count from
71 *
72 * This operation is non-atomic and can be reordered.
73 * If two examples of this operation race, one can appear to succeed
74 * but actually fail. You must protect multiple accesses with a lock.
75 */
76static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
77{
78 unsigned long mask = BIT_MASK(nr);
79 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
80 unsigned long old = *p;
81
82 *p = old & ~mask;
83 return (old & mask) != 0;
84}
85
86/* WARNING: non atomic and it can be reordered! */
87static inline int __test_and_change_bit(int nr,
88 volatile unsigned long *addr)
89{
90 unsigned long mask = BIT_MASK(nr);
91 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
92 unsigned long old = *p;
93
94 *p = old ^ mask;
95 return (old & mask) != 0;
96}
97
98/**
99 * test_bit - Determine whether a bit is set
100 * @nr: bit number to test
101 * @addr: Address to start counting from
102 */
103static inline int test_bit(int nr, const volatile unsigned long *addr)
104{
105 return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
106}
107
108#endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */