ocfs2: Separate out dlm lock functions.

This is the first in a series of patches to isolate ocfs2 from the
underlying cluster stack. Here we wrap the dlm locking functions with
ocfs2-specific calls. Because ocfs2 always uses the same dlm lock status
callbacks, we can eliminate the callbacks from the filesystem visible
functions.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

fs/ocfs2/stackglue.c

@@ -0,0 +1,65 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * stackglue.c
+ *
+ * Code which implements an OCFS2 specific interface to underlying
+ * cluster stacks.
+ *
+ * Copyright (C) 2007 Oracle.  All rights reserved.
+ *
+ * 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, version 2.
+ *
+ * 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.
+ */
+
+#include <linux/types.h>
+#include <linux/list.h>
+
+#include "dlm/dlmapi.h"
+
+#include "stackglue.h"
+
+static struct ocfs2_locking_protocol *lproto;
+
+enum dlm_status ocfs2_dlm_lock(struct dlm_ctxt *dlm,
+		   int mode,
+		   struct dlm_lockstatus *lksb,
+		   u32 flags,
+		   void *name,
+		   unsigned int namelen,
+		   void *astarg)
+{
+	BUG_ON(lproto == NULL);
+	return dlmlock(dlm, mode, lksb, flags, name, namelen,
+		       lproto->lp_lock_ast, astarg,
+		       lproto->lp_blocking_ast);
+}
+
+enum dlm_status ocfs2_dlm_unlock(struct dlm_ctxt *dlm,
+		     struct dlm_lockstatus *lksb,
+		     u32 flags,
+		     void *astarg)
+{
+	BUG_ON(lproto == NULL);
+
+	return dlmunlock(dlm, lksb, flags, lproto->lp_unlock_ast, astarg);
+}
+
+
+void o2cb_get_stack(struct ocfs2_locking_protocol *proto)
+{
+	BUG_ON(proto == NULL);
+
+	lproto = proto;
+}
+
+void o2cb_put_stack(void)
+{
+	lproto = NULL;
+}