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-rw-r--r--include/linux/refcount.h130
1 files changed, 65 insertions, 65 deletions
diff --git a/include/linux/refcount.h b/include/linux/refcount.h
index 7fabb1af18e0..497990c69b0b 100644
--- a/include/linux/refcount.h
+++ b/include/linux/refcount.h
@@ -147,24 +147,6 @@ static inline unsigned int refcount_read(const refcount_t *r)
return atomic_read(&r->refs);
}
-/**
- * refcount_add_not_zero - add a value to a refcount unless it is 0
- * @i: the value to add to the refcount
- * @r: the refcount
- *
- * Will saturate at REFCOUNT_SATURATED and WARN.
- *
- * Provides no memory ordering, it is assumed the caller has guaranteed the
- * object memory to be stable (RCU, etc.). It does provide a control dependency
- * and thereby orders future stores. See the comment on top.
- *
- * Use of this function is not recommended for the normal reference counting
- * use case in which references are taken and released one at a time. In these
- * cases, refcount_inc(), or one of its variants, should instead be used to
- * increment a reference count.
- *
- * Return: false if the passed refcount is 0, true otherwise
- */
static inline __must_check bool __refcount_add_not_zero(int i, refcount_t *r, int *oldp)
{
int old = refcount_read(r);
@@ -183,17 +165,12 @@ static inline __must_check bool __refcount_add_not_zero(int i, refcount_t *r, in
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
+ * refcount_add_not_zero - add a value to a refcount unless it is 0
* @i: the value to add to the refcount
* @r: the refcount
*
- * Similar to atomic_add(), but will saturate at REFCOUNT_SATURATED and WARN.
+ * Will saturate at REFCOUNT_SATURATED and WARN.
*
* Provides no memory ordering, it is assumed the caller has guaranteed the
* object memory to be stable (RCU, etc.). It does provide a control dependency
@@ -203,7 +180,14 @@ static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r)
* use case in which references are taken and released one at a time. In these
* cases, refcount_inc(), or one of its variants, should instead be used to
* increment a reference count.
+ *
+ * Return: false if the passed refcount is 0, true otherwise
*/
+static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r)
+{
+ return __refcount_add_not_zero(i, r, NULL);
+}
+
static inline void __refcount_add(int i, refcount_t *r, int *oldp)
{
int old = atomic_fetch_add_relaxed(i, &r->refs);
@@ -217,11 +201,32 @@ static inline void __refcount_add(int i, refcount_t *r, int *oldp)
refcount_warn_saturate(r, REFCOUNT_ADD_OVF);
}
+/**
+ * refcount_add - add a value to a refcount
+ * @i: the value to add to the refcount
+ * @r: the refcount
+ *
+ * Similar to atomic_add(), but will saturate at REFCOUNT_SATURATED and WARN.
+ *
+ * Provides no memory ordering, it is assumed the caller has guaranteed the
+ * object memory to be stable (RCU, etc.). It does provide a control dependency
+ * and thereby orders future stores. See the comment on top.
+ *
+ * Use of this function is not recommended for the normal reference counting
+ * use case in which references are taken and released one at a time. In these
+ * 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)
{
__refcount_add(i, r, NULL);
}
+static inline __must_check bool __refcount_inc_not_zero(refcount_t *r, int *oldp)
+{
+ return __refcount_add_not_zero(1, r, oldp);
+}
+
/**
* refcount_inc_not_zero - increment a refcount unless it is 0
* @r: the refcount to increment
@@ -235,14 +240,14 @@ static inline void refcount_add(int i, refcount_t *r)
*
* Return: true if the increment was successful, false otherwise
*/
-static inline __must_check bool __refcount_inc_not_zero(refcount_t *r, int *oldp)
+static inline __must_check bool refcount_inc_not_zero(refcount_t *r)
{
- return __refcount_add_not_zero(1, r, oldp);
+ return __refcount_inc_not_zero(r, NULL);
}
-static inline __must_check bool refcount_inc_not_zero(refcount_t *r)
+static inline void __refcount_inc(refcount_t *r, int *oldp)
{
- return __refcount_inc_not_zero(r, NULL);
+ __refcount_add(1, r, oldp);
}
/**
@@ -257,14 +262,27 @@ static inline __must_check bool refcount_inc_not_zero(refcount_t *r)
* 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)
+static inline void refcount_inc(refcount_t *r)
{
- __refcount_add(1, r, oldp);
+ __refcount_inc(r, NULL);
}
-static inline void refcount_inc(refcount_t *r)
+static inline __must_check bool __refcount_sub_and_test(int i, refcount_t *r, int *oldp)
{
- __refcount_inc(r, NULL);
+ int old = atomic_fetch_sub_release(i, &r->refs);
+
+ if (oldp)
+ *oldp = old;
+
+ if (old == i) {
+ smp_acquire__after_ctrl_dep();
+ return true;
+ }
+
+ if (unlikely(old < 0 || old - i < 0))
+ refcount_warn_saturate(r, REFCOUNT_SUB_UAF);
+
+ return false;
}
/**
@@ -287,27 +305,14 @@ static inline void refcount_inc(refcount_t *r)
*
* Return: true if the resulting refcount is 0, false otherwise
*/
-static inline __must_check bool __refcount_sub_and_test(int i, refcount_t *r, int *oldp)
+static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r)
{
- int old = atomic_fetch_sub_release(i, &r->refs);
-
- if (oldp)
- *oldp = old;
-
- if (old == i) {
- smp_acquire__after_ctrl_dep();
- return true;
- }
-
- if (unlikely(old < 0 || old - i < 0))
- refcount_warn_saturate(r, REFCOUNT_SUB_UAF);
-
- return false;
+ return __refcount_sub_and_test(i, r, NULL);
}
-static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r)
+static inline __must_check bool __refcount_dec_and_test(refcount_t *r, int *oldp)
{
- return __refcount_sub_and_test(i, r, NULL);
+ return __refcount_sub_and_test(1, r, oldp);
}
/**
@@ -323,26 +328,11 @@ static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r)
*
* 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_dec_and_test(r, NULL);
}
-/**
- * refcount_dec - decrement a refcount
- * @r: the refcount
- *
- * Similar to atomic_dec(), it will WARN on underflow and fail to decrement
- * when saturated at REFCOUNT_SATURATED.
- *
- * Provides release memory ordering, such that prior loads and stores are done
- * before.
- */
static inline void __refcount_dec(refcount_t *r, int *oldp)
{
int old = atomic_fetch_sub_release(1, &r->refs);
@@ -354,6 +344,16 @@ static inline void __refcount_dec(refcount_t *r, int *oldp)
refcount_warn_saturate(r, REFCOUNT_DEC_LEAK);
}
+/**
+ * refcount_dec - decrement a refcount
+ * @r: the refcount
+ *
+ * Similar to atomic_dec(), it will WARN on underflow and fail to decrement
+ * when saturated at REFCOUNT_SATURATED.
+ *
+ * Provides release memory ordering, such that prior loads and stores are done
+ * before.
+ */
static inline void refcount_dec(refcount_t *r)
{
__refcount_dec(r, NULL);