xref: /freebsd/sys/compat/linuxkpi/common/include/linux/idr.h (revision 2cd53241538632fa1c731fbf85384b785e77bd1b)
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 #ifndef	_LINUXKPI_LINUX_IDR_H_
30 #define	_LINUXKPI_LINUX_IDR_H_
31 
32 #include <sys/param.h>
33 #include <sys/lock.h>
34 #include <sys/limits.h>
35 #include <sys/mutex.h>
36 
37 #include <linux/radix-tree.h>
38 #include <linux/gpf.h>
39 #include <linux/types.h>
40 
41 #define	IDR_BITS	5
42 #define	IDR_SIZE	(1 << IDR_BITS)
43 #define	IDR_MASK	(IDR_SIZE - 1)
44 
45 #define	MAX_ID_SHIFT	((sizeof(int) * NBBY) - 1)
46 #define	MAX_ID_BIT	(1U << MAX_ID_SHIFT)
47 #define	MAX_ID_MASK	(MAX_ID_BIT - 1)
48 #define	MAX_LEVEL	(MAX_ID_SHIFT + IDR_BITS - 1) / IDR_BITS
49 
50 #define MAX_IDR_SHIFT (sizeof(int)*8 - 1)
51 #define MAX_IDR_BIT (1U << MAX_IDR_SHIFT)
52 #define MAX_IDR_MASK (MAX_IDR_BIT - 1)
53 
54 struct idr_layer {
55 	unsigned long		bitmap;
56 	struct idr_layer	*ary[IDR_SIZE];
57 };
58 
59 struct idr {
60 	struct mtx		lock;
61 	struct idr_layer	*top;
62 	struct idr_layer	*free;
63 	int			layers;
64 	int			next_cyclic_id;
65 };
66 
67 /* NOTE: It is the applications responsibility to destroy the IDR */
68 #define	DEFINE_IDR(name)						\
69 	struct idr name;						\
70 	SYSINIT(name##_idr_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST,	\
71 	    idr_init, &(name))
72 
73 /* NOTE: It is the applications responsibility to destroy the IDA */
74 #define	DEFINE_IDA(name)						\
75 	struct ida name;						\
76 	SYSINIT(name##_ida_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST,	\
77 	    ida_init, &(name))
78 
79 void	idr_preload(gfp_t gfp_mask);
80 void	idr_preload_end(void);
81 void	*idr_find(struct idr *idp, int id);
82 void	*idr_get_next(struct idr *idp, int *nextid);
83 bool	idr_is_empty(struct idr *idp);
84 int	idr_pre_get(struct idr *idp, gfp_t gfp_mask);
85 int	idr_get_new(struct idr *idp, void *ptr, int *id);
86 int	idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id);
87 void	*idr_replace(struct idr *idp, void *ptr, int id);
88 void	*idr_remove(struct idr *idp, int id);
89 void	idr_remove_all(struct idr *idp);
90 void	idr_destroy(struct idr *idp);
91 void	idr_init(struct idr *idp);
92 int	idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t);
93 int	idr_alloc_cyclic(struct idr *idp, void *ptr, int start, int end, gfp_t);
94 int	idr_for_each(struct idr *idp, int (*fn)(int id, void *p, void *data), void *data);
95 
96 #define	idr_for_each_entry(idp, entry, id)	\
97 	for ((id) = 0; ((entry) = idr_get_next(idp, &(id))) != NULL; ++(id))
98 
99 #define	IDA_CHUNK_SIZE		128	/* 128 bytes per chunk */
100 #define	IDA_BITMAP_LONGS	(IDA_CHUNK_SIZE / sizeof(long) - 1)
101 #define	IDA_BITMAP_BITS		(IDA_BITMAP_LONGS * sizeof(long) * 8)
102 
103 struct ida_bitmap {
104 	long			nr_busy;
105 	unsigned long		bitmap[IDA_BITMAP_LONGS];
106 };
107 
108 struct ida {
109 	struct idr		idr;
110 	struct ida_bitmap	*free_bitmap;
111 };
112 
113 int	ida_pre_get(struct ida *ida, gfp_t gfp_mask);
114 int	ida_get_new_above(struct ida *ida, int starting_id, int *p_id);
115 void	ida_remove(struct ida *ida, int id);
116 void	ida_destroy(struct ida *ida);
117 void	ida_init(struct ida *ida);
118 
119 int	ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
120     gfp_t gfp_mask);
121 void	ida_simple_remove(struct ida *ida, unsigned int id);
122 
123 static inline void
124 ida_free(struct ida *ida, int id)
125 {
126 
127 	ida_remove(ida, id);
128 }
129 
130 static inline int
131 ida_get_new(struct ida *ida, int *p_id)
132 {
133 
134 	return (ida_get_new_above(ida, 0, p_id));
135 }
136 
137 static inline int
138 ida_alloc_min(struct ida *ida, unsigned int min, gfp_t gfp)
139 {
140 	return (ida_simple_get(ida, min, UINT_MAX, gfp));
141 }
142 
143 static inline int
144 ida_alloc_max(struct ida *ida, unsigned int max, gfp_t gfp)
145 {
146 
147 	return (ida_simple_get(ida, 0, max, gfp));
148 }
149 
150 static inline int ida_alloc(struct ida *ida, gfp_t gfp)
151 {
152 	return (ida_alloc_max(ida, ~0u, gfp));
153 }
154 
155 static inline bool
156 ida_is_empty(struct ida *ida)
157 {
158 
159 	return (idr_is_empty(&ida->idr));
160 }
161 
162 #endif	/* _LINUXKPI_LINUX_IDR_H_ */
163