kobject: Export kobject_get_unless_zero()

Make the function available for outside use and fortify it against NULL
kobject.

CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/include/linux/kobject.h b/include/linux/kobject.h
index e6284591599ec5361b9abcffb2f731512b76eec9..ca85cb80e99a60e33df79e2ed0d8815953d1d21d 100644 (file)
--- a/include/linux/kobject.h
+++ b/include/linux/kobject.h
@@ -108,6 +108,8 @@ extern int __must_check kobject_rename(struct kobject *, const char *new_name);
 extern int __must_check kobject_move(struct kobject *, struct kobject *);
 
 extern struct kobject *kobject_get(struct kobject *kobj);
+extern struct kobject * __must_check kobject_get_unless_zero(
+                                               struct kobject *kobj);
 extern void kobject_put(struct kobject *kobj);
 
 extern const void *kobject_namespace(struct kobject *kobj);

diff --git a/lib/kobject.c b/lib/kobject.c
index 445dcaeb0f56de7882a1b1278a90ef7931f4099c..763d70a189410cb7307b87474801a662f631f806 100644 (file)
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -601,12 +601,15 @@ struct kobject *kobject_get(struct kobject *kobj)
 }
 EXPORT_SYMBOL(kobject_get);
 
-static struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
+struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
 {
+       if (!kobj)
+               return NULL;
        if (!kref_get_unless_zero(&kobj->kref))
                kobj = NULL;
        return kobj;
 }
+EXPORT_SYMBOL(kobject_get_unless_zero);
 
 /*
  * kobject_cleanup - free kobject resources.