linux/include/asm-generic/atomic-instrumented.h
Dmitry Vyukov ac605bee0b locking/atomic, asm-generic, x86: Add comments for atomic instrumentation
The comments are factored out from the code changes to make them
easier to read. Add them separately to explain some non-obvious
aspects.

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kasan-dev@googlegroups.com
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/cc595efc644bb905407012d82d3eb8bac3368e7a.1517246437.git.dvyukov@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 12:15:35 +01:00

477 lines
12 KiB
C

/*
* This file provides wrappers with KASAN instrumentation for atomic operations.
* To use this functionality an arch's atomic.h file needs to define all
* atomic operations with arch_ prefix (e.g. arch_atomic_read()) and include
* this file at the end. This file provides atomic_read() that forwards to
* arch_atomic_read() for actual atomic operation.
* Note: if an arch atomic operation is implemented by means of other atomic
* operations (e.g. atomic_read()/atomic_cmpxchg() loop), then it needs to use
* arch_ variants (i.e. arch_atomic_read()/arch_atomic_cmpxchg()) to avoid
* double instrumentation.
*/
#ifndef _LINUX_ATOMIC_INSTRUMENTED_H
#define _LINUX_ATOMIC_INSTRUMENTED_H
#include <linux/build_bug.h>
#include <linux/kasan-checks.h>
static __always_inline int atomic_read(const atomic_t *v)
{
kasan_check_read(v, sizeof(*v));
return arch_atomic_read(v);
}
static __always_inline s64 atomic64_read(const atomic64_t *v)
{
kasan_check_read(v, sizeof(*v));
return arch_atomic64_read(v);
}
static __always_inline void atomic_set(atomic_t *v, int i)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_set(v, i);
}
static __always_inline void atomic64_set(atomic64_t *v, s64 i)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_set(v, i);
}
static __always_inline int atomic_xchg(atomic_t *v, int i)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_xchg(v, i);
}
static __always_inline s64 atomic64_xchg(atomic64_t *v, s64 i)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_xchg(v, i);
}
static __always_inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_cmpxchg(v, old, new);
}
static __always_inline s64 atomic64_cmpxchg(atomic64_t *v, s64 old, s64 new)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_cmpxchg(v, old, new);
}
#ifdef arch_atomic_try_cmpxchg
#define atomic_try_cmpxchg atomic_try_cmpxchg
static __always_inline bool atomic_try_cmpxchg(atomic_t *v, int *old, int new)
{
kasan_check_write(v, sizeof(*v));
kasan_check_read(old, sizeof(*old));
return arch_atomic_try_cmpxchg(v, old, new);
}
#endif
#ifdef arch_atomic64_try_cmpxchg
#define atomic64_try_cmpxchg atomic64_try_cmpxchg
static __always_inline bool atomic64_try_cmpxchg(atomic64_t *v, s64 *old, s64 new)
{
kasan_check_write(v, sizeof(*v));
kasan_check_read(old, sizeof(*old));
return arch_atomic64_try_cmpxchg(v, old, new);
}
#endif
static __always_inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
kasan_check_write(v, sizeof(*v));
return __arch_atomic_add_unless(v, a, u);
}
static __always_inline bool atomic64_add_unless(atomic64_t *v, s64 a, s64 u)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_add_unless(v, a, u);
}
static __always_inline void atomic_inc(atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_inc(v);
}
static __always_inline void atomic64_inc(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_inc(v);
}
static __always_inline void atomic_dec(atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_dec(v);
}
static __always_inline void atomic64_dec(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_dec(v);
}
static __always_inline void atomic_add(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_add(i, v);
}
static __always_inline void atomic64_add(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_add(i, v);
}
static __always_inline void atomic_sub(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_sub(i, v);
}
static __always_inline void atomic64_sub(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_sub(i, v);
}
static __always_inline void atomic_and(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_and(i, v);
}
static __always_inline void atomic64_and(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_and(i, v);
}
static __always_inline void atomic_or(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_or(i, v);
}
static __always_inline void atomic64_or(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_or(i, v);
}
static __always_inline void atomic_xor(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic_xor(i, v);
}
static __always_inline void atomic64_xor(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
arch_atomic64_xor(i, v);
}
static __always_inline int atomic_inc_return(atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_inc_return(v);
}
static __always_inline s64 atomic64_inc_return(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_inc_return(v);
}
static __always_inline int atomic_dec_return(atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_dec_return(v);
}
static __always_inline s64 atomic64_dec_return(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_dec_return(v);
}
static __always_inline s64 atomic64_inc_not_zero(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_inc_not_zero(v);
}
static __always_inline s64 atomic64_dec_if_positive(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_dec_if_positive(v);
}
static __always_inline bool atomic_dec_and_test(atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_dec_and_test(v);
}
static __always_inline bool atomic64_dec_and_test(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_dec_and_test(v);
}
static __always_inline bool atomic_inc_and_test(atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_inc_and_test(v);
}
static __always_inline bool atomic64_inc_and_test(atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_inc_and_test(v);
}
static __always_inline int atomic_add_return(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_add_return(i, v);
}
static __always_inline s64 atomic64_add_return(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_add_return(i, v);
}
static __always_inline int atomic_sub_return(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_sub_return(i, v);
}
static __always_inline s64 atomic64_sub_return(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_sub_return(i, v);
}
static __always_inline int atomic_fetch_add(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_fetch_add(i, v);
}
static __always_inline s64 atomic64_fetch_add(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_fetch_add(i, v);
}
static __always_inline int atomic_fetch_sub(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_fetch_sub(i, v);
}
static __always_inline s64 atomic64_fetch_sub(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_fetch_sub(i, v);
}
static __always_inline int atomic_fetch_and(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_fetch_and(i, v);
}
static __always_inline s64 atomic64_fetch_and(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_fetch_and(i, v);
}
static __always_inline int atomic_fetch_or(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_fetch_or(i, v);
}
static __always_inline s64 atomic64_fetch_or(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_fetch_or(i, v);
}
static __always_inline int atomic_fetch_xor(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_fetch_xor(i, v);
}
static __always_inline s64 atomic64_fetch_xor(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_fetch_xor(i, v);
}
static __always_inline bool atomic_sub_and_test(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_sub_and_test(i, v);
}
static __always_inline bool atomic64_sub_and_test(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_sub_and_test(i, v);
}
static __always_inline bool atomic_add_negative(int i, atomic_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic_add_negative(i, v);
}
static __always_inline bool atomic64_add_negative(s64 i, atomic64_t *v)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_add_negative(i, v);
}
static __always_inline unsigned long
cmpxchg_size(volatile void *ptr, unsigned long old, unsigned long new, int size)
{
kasan_check_write(ptr, size);
switch (size) {
case 1:
return arch_cmpxchg((u8 *)ptr, (u8)old, (u8)new);
case 2:
return arch_cmpxchg((u16 *)ptr, (u16)old, (u16)new);
case 4:
return arch_cmpxchg((u32 *)ptr, (u32)old, (u32)new);
case 8:
BUILD_BUG_ON(sizeof(unsigned long) != 8);
return arch_cmpxchg((u64 *)ptr, (u64)old, (u64)new);
}
BUILD_BUG();
return 0;
}
#define cmpxchg(ptr, old, new) \
({ \
((__typeof__(*(ptr)))cmpxchg_size((ptr), (unsigned long)(old), \
(unsigned long)(new), sizeof(*(ptr)))); \
})
static __always_inline unsigned long
sync_cmpxchg_size(volatile void *ptr, unsigned long old, unsigned long new,
int size)
{
kasan_check_write(ptr, size);
switch (size) {
case 1:
return arch_sync_cmpxchg((u8 *)ptr, (u8)old, (u8)new);
case 2:
return arch_sync_cmpxchg((u16 *)ptr, (u16)old, (u16)new);
case 4:
return arch_sync_cmpxchg((u32 *)ptr, (u32)old, (u32)new);
case 8:
BUILD_BUG_ON(sizeof(unsigned long) != 8);
return arch_sync_cmpxchg((u64 *)ptr, (u64)old, (u64)new);
}
BUILD_BUG();
return 0;
}
#define sync_cmpxchg(ptr, old, new) \
({ \
((__typeof__(*(ptr)))sync_cmpxchg_size((ptr), \
(unsigned long)(old), (unsigned long)(new), \
sizeof(*(ptr)))); \
})
static __always_inline unsigned long
cmpxchg_local_size(volatile void *ptr, unsigned long old, unsigned long new,
int size)
{
kasan_check_write(ptr, size);
switch (size) {
case 1:
return arch_cmpxchg_local((u8 *)ptr, (u8)old, (u8)new);
case 2:
return arch_cmpxchg_local((u16 *)ptr, (u16)old, (u16)new);
case 4:
return arch_cmpxchg_local((u32 *)ptr, (u32)old, (u32)new);
case 8:
BUILD_BUG_ON(sizeof(unsigned long) != 8);
return arch_cmpxchg_local((u64 *)ptr, (u64)old, (u64)new);
}
BUILD_BUG();
return 0;
}
#define cmpxchg_local(ptr, old, new) \
({ \
((__typeof__(*(ptr)))cmpxchg_local_size((ptr), \
(unsigned long)(old), (unsigned long)(new), \
sizeof(*(ptr)))); \
})
static __always_inline u64
cmpxchg64_size(volatile u64 *ptr, u64 old, u64 new)
{
kasan_check_write(ptr, sizeof(*ptr));
return arch_cmpxchg64(ptr, old, new);
}
#define cmpxchg64(ptr, old, new) \
({ \
((__typeof__(*(ptr)))cmpxchg64_size((ptr), (u64)(old), \
(u64)(new))); \
})
static __always_inline u64
cmpxchg64_local_size(volatile u64 *ptr, u64 old, u64 new)
{
kasan_check_write(ptr, sizeof(*ptr));
return arch_cmpxchg64_local(ptr, old, new);
}
#define cmpxchg64_local(ptr, old, new) \
({ \
((__typeof__(*(ptr)))cmpxchg64_local_size((ptr), (u64)(old), \
(u64)(new))); \
})
/*
* Originally we had the following code here:
* __typeof__(p1) ____p1 = (p1);
* kasan_check_write(____p1, 2 * sizeof(*____p1));
* arch_cmpxchg_double(____p1, (p2), (o1), (o2), (n1), (n2));
* But it leads to compilation failures (see gcc issue 72873).
* So for now it's left non-instrumented.
* There are few callers of cmpxchg_double(), so it's not critical.
*/
#define cmpxchg_double(p1, p2, o1, o2, n1, n2) \
({ \
arch_cmpxchg_double((p1), (p2), (o1), (o2), (n1), (n2)); \
})
#define cmpxchg_double_local(p1, p2, o1, o2, n1, n2) \
({ \
arch_cmpxchg_double_local((p1), (p2), (o1), (o2), (n1), (n2)); \
})
#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */