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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
4117b021 AM |
2 | #ifndef _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ |
3 | #define _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ | |
4 | ||
5 | #include <asm/types.h> | |
6 | ||
4117b021 AM |
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 | */ | |
16 | static inline void __set_bit(int nr, volatile unsigned long *addr) | |
17 | { | |
d05be13b JS |
18 | unsigned long mask = BIT_MASK(nr); |
19 | unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); | |
4117b021 AM |
20 | |
21 | *p |= mask; | |
22 | } | |
23 | ||
24 | static inline void __clear_bit(int nr, volatile unsigned long *addr) | |
25 | { | |
d05be13b JS |
26 | unsigned long mask = BIT_MASK(nr); |
27 | unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); | |
4117b021 AM |
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 | */ | |
41 | static inline void __change_bit(int nr, volatile unsigned long *addr) | |
42 | { | |
d05be13b JS |
43 | unsigned long mask = BIT_MASK(nr); |
44 | unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); | |
4117b021 AM |
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 | */ | |
58 | static inline int __test_and_set_bit(int nr, volatile unsigned long *addr) | |
59 | { | |
d05be13b JS |
60 | unsigned long mask = BIT_MASK(nr); |
61 | unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); | |
4117b021 AM |
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 | */ | |
77 | static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr) | |
78 | { | |
d05be13b JS |
79 | unsigned long mask = BIT_MASK(nr); |
80 | unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); | |
4117b021 AM |
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! */ | |
88 | static inline int __test_and_change_bit(int nr, | |
89 | volatile unsigned long *addr) | |
90 | { | |
d05be13b JS |
91 | unsigned long mask = BIT_MASK(nr); |
92 | unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); | |
4117b021 AM |
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 | */ | |
104 | static inline int test_bit(int nr, const volatile unsigned long *addr) | |
105 | { | |
d05be13b | 106 | return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1))); |
4117b021 AM |
107 | } |
108 | ||
109 | #endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */ |