1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice unmodified, this list of conditions, and the following
12 *    disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef	_LINUX_IDR_H_
30#define	_LINUX_IDR_H_
31
32#include <sys/kernel.h>
33
34#define	IDR_BITS	5
35#define	IDR_SIZE	(1 << IDR_BITS)
36#define	IDR_MASK	(IDR_SIZE - 1)
37
38#define	MAX_ID_SHIFT	((sizeof(int) * NBBY) - 1)
39#define	MAX_ID_BIT	(1U << MAX_ID_SHIFT)
40#define	MAX_ID_MASK	(MAX_ID_BIT - 1)
41#define	MAX_LEVEL	(MAX_ID_SHIFT + IDR_BITS - 1) / IDR_BITS
42
43#define MAX_IDR_SHIFT (sizeof(int)*8 - 1)
44#define MAX_IDR_BIT (1U << MAX_IDR_SHIFT)
45#define MAX_IDR_MASK (MAX_IDR_BIT - 1)
46
47struct idr_layer {
48	unsigned long		bitmap;
49	struct idr_layer	*ary[IDR_SIZE];
50};
51
52struct idr {
53	struct mtx		lock;
54	struct idr_layer	*top;
55	struct idr_layer	*free;
56	int			layers;
57};
58
59#define DEFINE_IDR(name)						\
60	struct idr name;						\
61	SYSINIT(name##_idr_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST,	\
62	    idr_init, &(name));
63
64void	*idr_find(struct idr *idp, int id);
65int	idr_pre_get(struct idr *idp, gfp_t gfp_mask);
66int	idr_get_new(struct idr *idp, void *ptr, int *id);
67int	idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id);
68void	*idr_replace(struct idr *idp, void *ptr, int id);
69void	idr_remove(struct idr *idp, int id);
70void	idr_remove_all(struct idr *idp);
71void	idr_destroy(struct idr *idp);
72void	idr_init(struct idr *idp);
73
74#endif	/* _LINUX_IDR_H_ */
75