1 /* SPDX-License-Identifier: GPL-2.0 */
4 * This file provides wrappers with sanitizer instrumentation for bit
7 * To use this functionality, an arch's bitops.h file needs to define each of
8 * the below bit operations with an arch_ prefix (e.g. arch_set_bit(),
9 * arch___set_bit(), etc.).
11 #ifndef _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H
12 #define _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H
14 #include <linux/instrumented.h>
17 * clear_bit_unlock - Clear a bit in memory, for unlock
19 * @addr: the address to start counting from
21 * This operation is atomic and provides release barrier semantics.
23 static inline void clear_bit_unlock(long nr, volatile unsigned long *addr)
26 instrument_atomic_write(addr + BIT_WORD(nr), sizeof(long));
27 arch_clear_bit_unlock(nr, addr);
31 * __clear_bit_unlock - Clears a bit in memory
33 * @addr: Address to start counting from
35 * This is a non-atomic operation but implies a release barrier before the
36 * memory operation. It can be used for an unlock if no other CPUs can
37 * concurrently modify other bits in the word.
39 static inline void __clear_bit_unlock(long nr, volatile unsigned long *addr)
42 instrument_write(addr + BIT_WORD(nr), sizeof(long));
43 arch___clear_bit_unlock(nr, addr);
47 * test_and_set_bit_lock - Set a bit and return its old value, for lock
49 * @addr: Address to count from
51 * This operation is atomic and provides acquire barrier semantics if
52 * the returned value is 0.
53 * It can be used to implement bit locks.
55 static inline bool test_and_set_bit_lock(long nr, volatile unsigned long *addr)
57 instrument_atomic_read_write(addr + BIT_WORD(nr), sizeof(long));
58 return arch_test_and_set_bit_lock(nr, addr);
61 #if defined(arch_clear_bit_unlock_is_negative_byte)
63 * clear_bit_unlock_is_negative_byte - Clear a bit in memory and test if bottom
64 * byte is negative, for unlock.
65 * @nr: the bit to clear
66 * @addr: the address to start counting from
68 * This operation is atomic and provides release barrier semantics.
70 * This is a bit of a one-trick-pony for the filemap code, which clears
71 * PG_locked and tests PG_waiters,
74 clear_bit_unlock_is_negative_byte(long nr, volatile unsigned long *addr)
77 instrument_atomic_write(addr + BIT_WORD(nr), sizeof(long));
78 return arch_clear_bit_unlock_is_negative_byte(nr, addr);
80 /* Let everybody know we have it. */
81 #define clear_bit_unlock_is_negative_byte clear_bit_unlock_is_negative_byte
84 #endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H */