kref: add kref_set()

This adds kref_set() to the kref api for future use by people who really
know what they are doing with krefs...

From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 14 insertions, 2 deletions

diff --git a/include/linux/kref.h b/include/linux/kref.h
index 6fee3539893f..5d185635786e 100644
--- a/include/linux/kref.h
+++ b/include/linux/kref.h
@@ -24,6 +24,7 @@ struct kref {
         atomic_t refcount;
 };
 
+void kref_set(struct kref *kref, int num);
 void kref_init(struct kref *kref);
 void kref_get(struct kref *kref);
 int kref_put(struct kref *kref, void (*release) (struct kref *kref));
diff --git a/lib/kref.c b/lib/kref.c
index a6dc3ec328e0..9ecd6e865610 100644
--- a/lib/kref.c
+++ b/lib/kref.c
@@ -15,13 +15,23 @@
 #include <linux/module.h>
 
 /**
+ * kref_set - initialize object and set refcount to requested number.
+ * @kref: object in question.
+ * @num: initial reference counter
+ */
+void kref_set(struct kref *kref, int num)
+{
+        atomic_set(&kref->refcount, num);
+        smp_mb();
+}
+
+/**
  * kref_init - initialize object.
  * @kref: object in question.
  */
 void kref_init(struct kref *kref)
 {
-        atomic_set(&kref->refcount,1);
-        smp_mb();
+        kref_set(kref, 1);
 }
 
 /**
@@ -61,6 +71,7 @@ int kref_put(struct kref *kref, void (*release)(struct kref *kref))
         return 0;
 }
 
+EXPORT_SYMBOL(kref_set);
 EXPORT_SYMBOL(kref_init);
 EXPORT_SYMBOL(kref_get);
 EXPORT_SYMBOL(kref_put);