*
* Return: false if the passed refcount is 0, true otherwise
*/
-static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r)
+static inline __must_check bool __refcount_add_not_zero(int i, refcount_t *r, int *oldp)
{
int old = refcount_read(r);
break;
} while (!atomic_try_cmpxchg_relaxed(&r->refs, &old, old + i));
+ if (oldp)
+ *oldp = old;
+
if (unlikely(old < 0 || old + i < 0))
refcount_warn_saturate(r, REFCOUNT_ADD_NOT_ZERO_OVF);
return old;
}
+static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r)
+{
+ return __refcount_add_not_zero(i, r, NULL);
+}
+
/**
* refcount_add - add a value to a refcount
* @i: the value to add to the refcount
* cases, refcount_inc(), or one of its variants, should instead be used to
* increment a reference count.
*/
-static inline void refcount_add(int i, refcount_t *r)
+static inline void __refcount_add(int i, refcount_t *r, int *oldp)
{
int old = atomic_fetch_add_relaxed(i, &r->refs);
+ if (oldp)
+ *oldp = old;
+
if (unlikely(!old))
refcount_warn_saturate(r, REFCOUNT_ADD_UAF);
else if (unlikely(old < 0 || old + i < 0))
refcount_warn_saturate(r, REFCOUNT_ADD_OVF);
}
+static inline void refcount_add(int i, refcount_t *r)
+{
+ __refcount_add(i, r, NULL);
+}
+
/**
* refcount_inc_not_zero - increment a refcount unless it is 0
* @r: the refcount to increment
*
* Return: true if the increment was successful, false otherwise
*/
+static inline __must_check bool __refcount_inc_not_zero(refcount_t *r, int *oldp)
+{
+ return __refcount_add_not_zero(1, r, oldp);
+}
+
static inline __must_check bool refcount_inc_not_zero(refcount_t *r)
{
- return refcount_add_not_zero(1, r);
+ return __refcount_inc_not_zero(r, NULL);
}
/**
* Will WARN if the refcount is 0, as this represents a possible use-after-free
* condition.
*/
+static inline void __refcount_inc(refcount_t *r, int *oldp)
+{
+ __refcount_add(1, r, oldp);
+}
+
static inline void refcount_inc(refcount_t *r)
{
- refcount_add(1, r);
+ __refcount_inc(r, NULL);
}
/**
*
* Return: true if the resulting refcount is 0, false otherwise
*/
-static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r)
+static inline __must_check bool __refcount_sub_and_test(int i, refcount_t *r, int *oldp)
{
int old = atomic_fetch_sub_release(i, &r->refs);
+ if (oldp)
+ *oldp = old;
+
if (old == i) {
smp_acquire__after_ctrl_dep();
return true;
return false;
}
+static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r)
+{
+ return __refcount_sub_and_test(i, r, NULL);
+}
+
/**
* refcount_dec_and_test - decrement a refcount and test if it is 0
* @r: the refcount
*
* Return: true if the resulting refcount is 0, false otherwise
*/
+static inline __must_check bool __refcount_dec_and_test(refcount_t *r, int *oldp)
+{
+ return __refcount_sub_and_test(1, r, oldp);
+}
+
static inline __must_check bool refcount_dec_and_test(refcount_t *r)
{
- return refcount_sub_and_test(1, r);
+ return __refcount_dec_and_test(r, NULL);
}
/**
* Provides release memory ordering, such that prior loads and stores are done
* before.
*/
-static inline void refcount_dec(refcount_t *r)
+static inline void __refcount_dec(refcount_t *r, int *oldp)
{
- if (unlikely(atomic_fetch_sub_release(1, &r->refs) <= 1))
+ int old = atomic_fetch_sub_release(1, &r->refs);
+
+ if (oldp)
+ *oldp = old;
+
+ if (unlikely(old <= 1))
refcount_warn_saturate(r, REFCOUNT_DEC_LEAK);
}
+static inline void refcount_dec(refcount_t *r)
+{
+ __refcount_dec(r, NULL);
+}
+
extern __must_check bool refcount_dec_if_one(refcount_t *r);
extern __must_check bool refcount_dec_not_one(refcount_t *r);
extern __must_check bool refcount_dec_and_mutex_lock(refcount_t *r, struct mutex *lock);