/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
 * vim:expandtab:shiftwidth=8:tabstop=8:
 *
 * GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * 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 version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see
 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 */

#ifndef __LUSTRE_HANDLES_H_
#define __LUSTRE_HANDLES_H_

/** \defgroup handles handles
 *
 * @{
 */

#if defined(__linux__)
#include <linux/lustre_handles.h>
#elif defined(__APPLE__)
#include <darwin/lustre_handles.h>
#elif defined(__WINNT__)
#include <winnt/lustre_handles.h>
#else
#error Unsupported operating system.
#endif

#include <libcfs/libcfs.h>

typedef void (*portals_handle_addref_cb)(void *object);

/* These handles are most easily used by having them appear at the very top of
 * whatever object that you want to make handles for.  ie:
 *
 * struct ldlm_lock {
 *         struct portals_handle handle;
 *         ...
 * };
 *
 * Now you're able to assign the results of cookie2handle directly to an
 * ldlm_lock.  If it's not at the top, you'll want to hack up a macro that
 * uses some offsetof() magic. */

struct portals_handle {
        cfs_list_t h_link;
        __u64 h_cookie;
        portals_handle_addref_cb h_addref;

        /* newly added fields to handle the RCU issue. -jxiong */
        cfs_spinlock_t h_lock;
        void *h_ptr;
        void (*h_free_cb)(void *, size_t);
        cfs_rcu_head_t h_rcu;
        unsigned int h_size;
        __u8 h_in:1;
        __u8 h_unused[3];
};
#define RCU2HANDLE(rcu)    container_of(rcu, struct portals_handle, h_rcu)

/* handles.c */

/* Add a handle to the hash table */
void class_handle_hash(struct portals_handle *, portals_handle_addref_cb);
void class_handle_unhash(struct portals_handle *);
void class_handle_hash_back(struct portals_handle *);
void *class_handle2object(__u64 cookie);
void class_handle_free_cb(cfs_rcu_head_t *);
int class_handle_init(void);
void class_handle_cleanup(void);

/** @} handles */

#endif