/*
 * Copyright (c) 2005-2012 The DragonFly Project.
 * Copyright (c) 2013 François Tigeot
 * All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Jeffrey Hsu.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name of The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

/**
 * IDR is a small Integer ID management library that provides an interface to
 * map integers with some pointer that can later be retrieved.
 *
 * NOTE: Maintains compatibility with linux, allowing NULL pointers.
 */


#ifndef _SYS_IDR_H_
#define _SYS_IDR_H_

#ifdef _KERNEL

#include <sys/thread.h>

struct idr_node {
        void    *data;
        int      allocated;
};

struct idr {
        struct      idr_node *idr_nodes;
        int         idr_count;
        int         idr_lastindex;
        int         idr_freeindex;
        int         idr_nexpands;
        int         idr_maxwant;
        struct lwkt_token idr_token;
};

void    *idr_find(struct idr *idp, int id);
void    *idr_replace(struct idr *idp, void *ptr, int id);
void    *idr_remove(struct idr *idp, int id);
void     idr_remove_all(struct idr *idp);
void     idr_destroy(struct idr *idp);
int      idr_for_each(struct idr *idp, int (*fn)(int id, void *p, void *data), void *data);
int      idr_get_new(struct idr *idp, void *ptr, int *id);
int      idr_get_new_above(struct idr *idp, void *ptr, int sid, int *id);
int      idr_pre_get(struct idr *idp, unsigned gfp_mask);

void     idr_init(struct idr *idp);

int idr_alloc(struct idr *idp, void *ptr, int start, int end, unsigned gfp_mask);

static inline void idr_preload(unsigned gfp_mask)
{
        /* Linux disables preemption and allocates a per-cpu buffer here */
}

static inline void idr_preload_end(void)
{
        /* Linux re-enables preemption here */
}

#endif /* _KERNEL */

#endif /* !_SYS_IDR_H_ */