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