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| author | Kees Cook <kees+treewide@kernel.org> | 2026-09-02 15:31:14 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2026-09-04 21:37:00 -0700 |
| commit | 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch) | |
| tree | c65086f9bdcd48c6360fb7cb4598bca084da1f32 /include/asm-generic/bitops/lock.h | |
| download | linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip | |
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci
This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.
Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.
Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'include/asm-generic/bitops/lock.h')
| -rw-r--r-- | include/asm-generic/bitops/lock.h | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/include/asm-generic/bitops/lock.h b/include/asm-generic/bitops/lock.h new file mode 100644 index 000000000..ffb73b612 --- /dev/null +++ b/include/asm-generic/bitops/lock.h @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_GENERIC_BITOPS_LOCK_H_ +#define _ASM_GENERIC_BITOPS_LOCK_H_ + +#include <linux/atomic.h> +#include <linux/compiler.h> +#include <asm/barrier.h> + +/** + * arch_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 __always_inline int +arch_test_and_set_bit_lock(unsigned int nr, volatile unsigned long *addr) +{ + long old; + unsigned long mask = BIT_MASK(nr); + + addr += BIT_WORD(nr); + if (READ_ONCE(*addr) & mask) + return 1; + + old = raw_atomic_long_fetch_or_acquire(mask, (atomic_long_t *)addr); + return !!(old & mask); +} + + +/** + * arch_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 __always_inline void +arch_clear_bit_unlock(unsigned int nr, volatile unsigned long *addr) +{ + addr += BIT_WORD(nr); + raw_atomic_long_fetch_andnot_release(BIT_MASK(nr), (atomic_long_t *)addr); +} + +/** + * arch___clear_bit_unlock - Clear a bit in memory, for unlock + * @nr: the bit to set + * @addr: the address to start counting from + * + * A weaker form of clear_bit_unlock() as used by __bit_lock_unlock(). If all + * the bits in the word are protected by this lock some archs can use weaker + * ops to safely unlock. + * + * See for example x86's implementation. + */ +static inline void +arch___clear_bit_unlock(unsigned int nr, volatile unsigned long *addr) +{ + unsigned long old; + + addr += BIT_WORD(nr); + old = READ_ONCE(*addr); + old &= ~BIT_MASK(nr); + raw_atomic_long_set_release((atomic_long_t *)addr, old); +} + +#ifndef arch_xor_unlock_is_negative_byte +static inline bool arch_xor_unlock_is_negative_byte(unsigned long mask, + volatile unsigned long *p) +{ + long old; + + old = raw_atomic_long_fetch_xor_release(mask, (atomic_long_t *)p); + return !!(old & BIT(7)); +} +#endif + +#include <asm-generic/bitops/instrumented-lock.h> + +#endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */ |
