summaryrefslogtreecommitdiff
path: root/lib/kref.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/kref.c')
-rw-r--r--lib/kref.c97
1 files changed, 0 insertions, 97 deletions
diff --git a/lib/kref.c b/lib/kref.c
deleted file mode 100644
index 3efb882b11d..00000000000
--- a/lib/kref.c
+++ /dev/null
@@ -1,97 +0,0 @@
-/*
- * kref.c - library routines for handling generic reference counted objects
- *
- * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
- * Copyright (C) 2004 IBM Corp.
- *
- * based on lib/kobject.c which was:
- * Copyright (C) 2002-2003 Patrick Mochel <mochel@osdl.org>
- *
- * This file is released under the GPLv2.
- *
- */
-
-#include <linux/kref.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-
-/**
- * kref_init - initialize object.
- * @kref: object in question.
- */
-void kref_init(struct kref *kref)
-{
- atomic_set(&kref->refcount, 1);
- smp_mb();
-}
-
-/**
- * kref_get - increment refcount for object.
- * @kref: object.
- */
-void kref_get(struct kref *kref)
-{
- WARN_ON(!atomic_read(&kref->refcount));
- atomic_inc(&kref->refcount);
- smp_mb__after_atomic_inc();
-}
-
-/**
- * kref_put - decrement refcount for object.
- * @kref: object.
- * @release: pointer to the function that will clean up the object when the
- * last reference to the object is released.
- * This pointer is required, and it is not acceptable to pass kfree
- * in as this function.
- *
- * Decrement the refcount, and if 0, call release().
- * Return 1 if the object was removed, otherwise return 0. Beware, if this
- * function returns 0, you still can not count on the kref from remaining in
- * memory. Only use the return value if you want to see if the kref is now
- * gone, not present.
- */
-int kref_put(struct kref *kref, void (*release)(struct kref *kref))
-{
- WARN_ON(release == NULL);
- WARN_ON(release == (void (*)(struct kref *))kfree);
-
- if (atomic_dec_and_test(&kref->refcount)) {
- release(kref);
- return 1;
- }
- return 0;
-}
-
-
-/**
- * kref_sub - subtract a number of refcounts for object.
- * @kref: object.
- * @count: Number of recounts to subtract.
- * @release: pointer to the function that will clean up the object when the
- * last reference to the object is released.
- * This pointer is required, and it is not acceptable to pass kfree
- * in as this function.
- *
- * Subtract @count from the refcount, and if 0, call release().
- * Return 1 if the object was removed, otherwise return 0. Beware, if this
- * function returns 0, you still can not count on the kref from remaining in
- * memory. Only use the return value if you want to see if the kref is now
- * gone, not present.
- */
-int kref_sub(struct kref *kref, unsigned int count,
- void (*release)(struct kref *kref))
-{
- WARN_ON(release == NULL);
- WARN_ON(release == (void (*)(struct kref *))kfree);
-
- if (atomic_sub_and_test((int) count, &kref->refcount)) {
- release(kref);
- return 1;
- }
- return 0;
-}
-
-EXPORT_SYMBOL(kref_init);
-EXPORT_SYMBOL(kref_get);
-EXPORT_SYMBOL(kref_put);
-EXPORT_SYMBOL(kref_sub);