ocfs2: Add extended attribute support

This patch implements storing extended attributes both in inode or a single
external block. We only store EA's in-inode when blocksize > 512 or that
inode block has free space for it. When an EA's value is larger than 80
bytes, we will store the value via b-tree outside inode or block.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/xattr.h b/fs/ocfs2/xattr.h
new file mode 100644
index 0000000..ed32377
--- /dev/null
+++ b/fs/ocfs2/xattr.h
@@ -0,0 +1,51 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * xattr.h
+ *
+ * Function prototypes
+ *
+ * Copyright (C) 2008 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; 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., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef OCFS2_XATTR_H
+#define OCFS2_XATTR_H
+
+#include <linux/init.h>
+#include <linux/xattr.h>
+
+enum ocfs2_xattr_type {
+	OCFS2_XATTR_INDEX_USER = 1,
+	OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS,
+	OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT,
+	OCFS2_XATTR_INDEX_TRUSTED,
+	OCFS2_XATTR_INDEX_SECURITY,
+	OCFS2_XATTR_MAX
+};
+
+extern struct xattr_handler ocfs2_xattr_user_handler;
+extern struct xattr_handler ocfs2_xattr_trusted_handler;
+
+extern ssize_t ocfs2_listxattr(struct dentry *, char *, size_t);
+extern int ocfs2_xattr_get(struct inode *, int, const char *, void *, size_t);
+extern int ocfs2_xattr_set(struct inode *, int, const char *, const void *,
+			   size_t, int);
+extern int ocfs2_xattr_remove(struct inode *inode, struct buffer_head *di_bh);
+extern struct xattr_handler *ocfs2_xattr_handlers[];
+
+#endif /* OCFS2_XATTR_H */