xref: /freebsd/sys/compat/linuxkpi/common/include/linux/idr.h (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice unmodified, this list of conditions, and the following
13  *    disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 #ifndef	_LINUX_IDR_H_
32 #define	_LINUX_IDR_H_
33 
34 #include <sys/param.h>
35 #include <sys/lock.h>
36 #include <sys/mutex.h>
37 
38 #include <linux/types.h>
39 
40 #define	IDR_BITS	5
41 #define	IDR_SIZE	(1 << IDR_BITS)
42 #define	IDR_MASK	(IDR_SIZE - 1)
43 
44 #define	MAX_ID_SHIFT	((sizeof(int) * NBBY) - 1)
45 #define	MAX_ID_BIT	(1U << MAX_ID_SHIFT)
46 #define	MAX_ID_MASK	(MAX_ID_BIT - 1)
47 #define	MAX_LEVEL	(MAX_ID_SHIFT + IDR_BITS - 1) / IDR_BITS
48 
49 #define MAX_IDR_SHIFT (sizeof(int)*8 - 1)
50 #define MAX_IDR_BIT (1U << MAX_IDR_SHIFT)
51 #define MAX_IDR_MASK (MAX_IDR_BIT - 1)
52 
53 struct idr_layer {
54 	unsigned long		bitmap;
55 	struct idr_layer	*ary[IDR_SIZE];
56 };
57 
58 struct idr {
59 	struct mtx		lock;
60 	struct idr_layer	*top;
61 	struct idr_layer	*free;
62 	int			layers;
63 	int			next_cyclic_id;
64 };
65 
66 /* NOTE: It is the applications responsibility to destroy the IDR */
67 #define	DEFINE_IDR(name)						\
68 	struct idr name;						\
69 	SYSINIT(name##_idr_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST,	\
70 	    idr_init, &(name))
71 
72 /* NOTE: It is the applications responsibility to destroy the IDA */
73 #define	DEFINE_IDA(name)						\
74 	struct ida name;						\
75 	SYSINIT(name##_ida_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST,	\
76 	    ida_init, &(name))
77 
78 #define	idr_preload(x) do { } while (0)
79 #define	idr_preload_end() do { } while (0)
80 
81 void	*idr_find(struct idr *idp, int id);
82 void	*idr_get_next(struct idr *idp, int *nextid);
83 int	idr_pre_get(struct idr *idp, gfp_t gfp_mask);
84 int	idr_get_new(struct idr *idp, void *ptr, int *id);
85 int	idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id);
86 void	*idr_replace(struct idr *idp, void *ptr, int id);
87 void	idr_remove(struct idr *idp, int id);
88 void	idr_remove_all(struct idr *idp);
89 void	idr_destroy(struct idr *idp);
90 void	idr_init(struct idr *idp);
91 int	idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t);
92 int	idr_alloc_cyclic(struct idr *idp, void *ptr, int start, int end, gfp_t);
93 int	idr_for_each(struct idr *idp, int (*fn)(int id, void *p, void *data), void *data);
94 
95 #define	idr_for_each_entry(idp, entry, id)	\
96 	for ((id) = 0; ((entry) = idr_get_next(idp, &(id))) != NULL; ++(id))
97 
98 #define	IDA_CHUNK_SIZE		128	/* 128 bytes per chunk */
99 #define	IDA_BITMAP_LONGS	(IDA_CHUNK_SIZE / sizeof(long) - 1)
100 #define	IDA_BITMAP_BITS 	(IDA_BITMAP_LONGS * sizeof(long) * 8)
101 
102 struct ida_bitmap {
103 	long			nr_busy;
104 	unsigned long		bitmap[IDA_BITMAP_LONGS];
105 };
106 
107 struct ida {
108 	struct idr		idr;
109 	struct ida_bitmap	*free_bitmap;
110 };
111 
112 int	ida_pre_get(struct ida *ida, gfp_t gfp_mask);
113 int	ida_get_new_above(struct ida *ida, int starting_id, int *p_id);
114 void	ida_remove(struct ida *ida, int id);
115 void	ida_destroy(struct ida *ida);
116 void	ida_init(struct ida *ida);
117 
118 int	ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
119     gfp_t gfp_mask);
120 void	ida_simple_remove(struct ida *ida, unsigned int id);
121 
122 static inline int
123 ida_get_new(struct ida *ida, int *p_id)
124 {
125 	return (ida_get_new_above(ida, 0, p_id));
126 }
127 
128 #endif	/* _LINUX_IDR_H_ */
129