locking/atomic/x86: Use 's64 *' for 'old' argument of atomic64_try_cmpxchg()

atomic64_try_cmpxchg() declares old argument as 'long *',
this makes it impossible to use it in portable code.
If caller passes 'long *', it becomes 32-bits on 32-bit arches.
If caller passes 's64 *', it does not compile on x86_64.

Change type of old argument to 's64 *' instead.

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/fa6f77f2375150d26ea796a77e8b59195fd2ab13.1497690003.git.dvyukov@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h
index 8db8879a6d8cbb31d4d7264b52f289e0170d8b37..5d9de36a2f04cf17d879d7dcf3d712cf6a9c2ff2 100644 (file)
--- a/arch/x86/include/asm/atomic64_64.h
+++ b/arch/x86/include/asm/atomic64_64.h
@@ -177,7 +177,7 @@ static inline long atomic64_cmpxchg(atomic64_t *v, long old, long new)
 }
 
 #define atomic64_try_cmpxchg atomic64_try_cmpxchg
-static __always_inline bool atomic64_try_cmpxchg(atomic64_t *v, long *old, long new)
+static __always_inline bool atomic64_try_cmpxchg(atomic64_t *v, s64 *old, long new)
 {
        return try_cmpxchg(&v->counter, old, new);
 }
@@ -198,7 +198,7 @@ static inline long atomic64_xchg(atomic64_t *v, long new)
  */
 static inline bool atomic64_add_unless(atomic64_t *v, long a, long u)
 {
-       long c = atomic64_read(v);
+       s64 c = atomic64_read(v);
        do {
                if (unlikely(c == u))
                        return false;
@@ -217,7 +217,7 @@ static inline bool atomic64_add_unless(atomic64_t *v, long a, long u)
  */
 static inline long atomic64_dec_if_positive(atomic64_t *v)
 {
-       long dec, c = atomic64_read(v);
+       s64 dec, c = atomic64_read(v);
        do {
                dec = c - 1;
                if (unlikely(dec < 0))
@@ -236,7 +236,7 @@ static inline void atomic64_and(long i, atomic64_t *v)
 
 static inline long atomic64_fetch_and(long i, atomic64_t *v)
 {
-       long val = atomic64_read(v);
+       s64 val = atomic64_read(v);
 
        do {
        } while (!atomic64_try_cmpxchg(v, &val, val & i));
@@ -253,7 +253,7 @@ static inline void atomic64_or(long i, atomic64_t *v)
 
 static inline long atomic64_fetch_or(long i, atomic64_t *v)
 {
-       long val = atomic64_read(v);
+       s64 val = atomic64_read(v);
 
        do {
        } while (!atomic64_try_cmpxchg(v, &val, val | i));
@@ -270,7 +270,7 @@ static inline void atomic64_xor(long i, atomic64_t *v)
 
 static inline long atomic64_fetch_xor(long i, atomic64_t *v)
 {
-       long val = atomic64_read(v);
+       s64 val = atomic64_read(v);
 
        do {
        } while (!atomic64_try_cmpxchg(v, &val, val ^ i));

diff --git a/arch/x86/include/asm/cmpxchg.h b/arch/x86/include/asm/cmpxchg.h
index d90296d061e8267a97cd8a58328d8a20534289d4..b5069e802d5ce4acbe9f8ac61f47401db8f1f54d 100644 (file)
--- a/arch/x86/include/asm/cmpxchg.h
+++ b/arch/x86/include/asm/cmpxchg.h
@@ -157,7 +157,7 @@ extern void __add_wrong_size(void)
 #define __raw_try_cmpxchg(_ptr, _pold, _new, size, lock)               \
 ({                                                                     \
        bool success;                                                   \
-       __typeof__(_ptr) _old = (_pold);                                \
+       __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold);              \
        __typeof__(*(_ptr)) __old = *_old;                              \
        __typeof__(*(_ptr)) __new = (_new);                             \
        switch (size) {                                                 \