From: Frank Mori Hess <fmhess@speakeasy.net>
Date: Mon, 21 Nov 2005 01:15:31 +0000 (+0000)
Subject: Added compatibility wrapper for kref.h
X-Git-Tag: r0_7_71~122
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=aa75cb08448aab4940cb61defbf635ab3a56eb77;p=comedi.git

Added compatibility wrapper for kref.h
---

diff --git a/include/linux/kref.h b/include/linux/kref.h
new file mode 100644
index 00000000..f7a51121
--- /dev/null
+++ b/include/linux/kref.h
@@ -0,0 +1,108 @@
+/*    
+
+Copyright (C) 2005 Frank Mori Hess <fmhess@users.sourceforge.net>
+2.4 compat code is based on kernel's lib/kref.c which was:
+Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
+Copyright (C) 2004 IBM Corp.
+Copyright (C) 2002-2003 Patrick Mochel <mochel@osdl.org>
+   
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifndef _KREF_COMPAT_H_
+#define _KREF_COMPAT_H_
+
+#include <linux/version.h>
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
+
+#include <linux/types.h>
+#include <asm/atomic.h>
+
+struct kref {
+	atomic_t refcount;
+};
+
+static inline void kref_init(struct kref *kref)
+{
+	atomic_set(&kref->refcount,1);
+}
+
+static inline void kref_get(struct kref *kref)
+{
+	atomic_inc(&kref->refcount);
+}
+
+static inline int kref_put(struct kref *kref, void (*release) (struct kref *kref))
+{
+	if (atomic_dec_and_test(&kref->refcount)) {
+		release(kref);
+		return 1;
+	}
+	return 0;
+}
+
+static inline void KREF_INIT(struct kref *kref, void (*release) (struct kref *kref))
+{
+	kref_init(kref);
+}
+
+static inline int KREF_PUT(struct kref *kref, void (*release) (struct kref *kref))
+{
+	return kref_put(kref, release);
+}
+
+#else
+
+#include_next <linux/kref.h>
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,9)
+
+static inline void KREF_INIT(struct kref *kref, void (*release) (struct kref *kref))
+{
+	kref_init(kref, release);
+}
+
+static inline int KREF_PUT(struct kref *kref, void (*release) (struct kref *kref))
+{
+	int retval;
+	if(atomic_read(&kref->refcount) == 1)
+	{
+		retval = 1;
+	}else
+	{
+		retval = 0;
+	}
+	kref_put(kref);
+	return retval;
+}
+
+#else
+
+static inline void KREF_INIT(struct kref *kref, void (*release) (struct kref *kref))
+{
+	kref_init(kref);
+}
+
+static inline int KREF_PUT(struct kref *kref, void (*release) (struct kref *kref))
+{
+	return kref_put(kref, release);
+}
+
+#endif	// LINUX_VERSION_CODE < KERNEL_VERSION(2,6,9)
+
+#endif	// LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
+
+#endif /* _KREF_COMPAT_H_ */