mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![Marco Elver](/assets/img/avatar_default.png)
Adds the required KCSAN instrumentation for barriers of atomic bitops. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
84 lines
2.6 KiB
C
84 lines
2.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
/*
|
|
* This file provides wrappers with sanitizer instrumentation for bit
|
|
* locking operations.
|
|
*
|
|
* To use this functionality, an arch's bitops.h file needs to define each of
|
|
* the below bit operations with an arch_ prefix (e.g. arch_set_bit(),
|
|
* arch___set_bit(), etc.).
|
|
*/
|
|
#ifndef _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H
|
|
#define _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H
|
|
|
|
#include <linux/instrumented.h>
|
|
|
|
/**
|
|
* clear_bit_unlock - Clear a bit in memory, for unlock
|
|
* @nr: the bit to set
|
|
* @addr: the address to start counting from
|
|
*
|
|
* This operation is atomic and provides release barrier semantics.
|
|
*/
|
|
static inline void clear_bit_unlock(long nr, volatile unsigned long *addr)
|
|
{
|
|
kcsan_release();
|
|
instrument_atomic_write(addr + BIT_WORD(nr), sizeof(long));
|
|
arch_clear_bit_unlock(nr, addr);
|
|
}
|
|
|
|
/**
|
|
* __clear_bit_unlock - Clears a bit in memory
|
|
* @nr: Bit to clear
|
|
* @addr: Address to start counting from
|
|
*
|
|
* This is a non-atomic operation but implies a release barrier before the
|
|
* memory operation. It can be used for an unlock if no other CPUs can
|
|
* concurrently modify other bits in the word.
|
|
*/
|
|
static inline void __clear_bit_unlock(long nr, volatile unsigned long *addr)
|
|
{
|
|
kcsan_release();
|
|
instrument_write(addr + BIT_WORD(nr), sizeof(long));
|
|
arch___clear_bit_unlock(nr, addr);
|
|
}
|
|
|
|
/**
|
|
* test_and_set_bit_lock - Set a bit and return its old value, for lock
|
|
* @nr: Bit to set
|
|
* @addr: Address to count from
|
|
*
|
|
* This operation is atomic and provides acquire barrier semantics if
|
|
* the returned value is 0.
|
|
* It can be used to implement bit locks.
|
|
*/
|
|
static inline bool test_and_set_bit_lock(long nr, volatile unsigned long *addr)
|
|
{
|
|
instrument_atomic_read_write(addr + BIT_WORD(nr), sizeof(long));
|
|
return arch_test_and_set_bit_lock(nr, addr);
|
|
}
|
|
|
|
#if defined(arch_clear_bit_unlock_is_negative_byte)
|
|
/**
|
|
* clear_bit_unlock_is_negative_byte - Clear a bit in memory and test if bottom
|
|
* byte is negative, for unlock.
|
|
* @nr: the bit to clear
|
|
* @addr: the address to start counting from
|
|
*
|
|
* This operation is atomic and provides release barrier semantics.
|
|
*
|
|
* This is a bit of a one-trick-pony for the filemap code, which clears
|
|
* PG_locked and tests PG_waiters,
|
|
*/
|
|
static inline bool
|
|
clear_bit_unlock_is_negative_byte(long nr, volatile unsigned long *addr)
|
|
{
|
|
kcsan_release();
|
|
instrument_atomic_write(addr + BIT_WORD(nr), sizeof(long));
|
|
return arch_clear_bit_unlock_is_negative_byte(nr, addr);
|
|
}
|
|
/* Let everybody know we have it. */
|
|
#define clear_bit_unlock_is_negative_byte clear_bit_unlock_is_negative_byte
|
|
#endif
|
|
|
|
#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H */
|