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12#ifndef __IDR_H__
13#define __IDR_H__
14
15#include <linux/types.h>
16#include <linux/bitops.h>
17#include <linux/init.h>
18#include <linux/rcupdate.h>
19
20#if BITS_PER_LONG == 32
21# define IDR_BITS 5
22# define IDR_FULL 0xfffffffful
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26# define TOP_LEVEL_FULL (IDR_FULL >> 30)
27#elif BITS_PER_LONG == 64
28# define IDR_BITS 6
29# define IDR_FULL 0xfffffffffffffffful
30
31
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33# define TOP_LEVEL_FULL (IDR_FULL >> 62)
34#else
35# error "BITS_PER_LONG is not 32 or 64"
36#endif
37
38#define IDR_SIZE (1 << IDR_BITS)
39#define IDR_MASK ((1 << IDR_BITS)-1)
40
41#define MAX_ID_SHIFT (sizeof(int)*8 - 1)
42#define MAX_ID_BIT (1U << MAX_ID_SHIFT)
43#define MAX_ID_MASK (MAX_ID_BIT - 1)
44
45
46#define MAX_LEVEL (MAX_ID_SHIFT + IDR_BITS - 1) / IDR_BITS
47
48
49#define IDR_FREE_MAX MAX_LEVEL + MAX_LEVEL
50
51struct idr_layer {
52 unsigned long bitmap;
53 struct idr_layer __rcu *ary[1<<IDR_BITS];
54 int count;
55 int layer;
56 struct rcu_head rcu_head;
57};
58
59struct idr {
60 struct idr_layer __rcu *top;
61 struct idr_layer *id_free;
62 int layers;
63 int id_free_cnt;
64 spinlock_t lock;
65};
66
67#define IDR_INIT(name) \
68{ \
69 .top = NULL, \
70 .id_free = NULL, \
71 .layers = 0, \
72 .id_free_cnt = 0, \
73 .lock = __SPIN_LOCK_UNLOCKED(name.lock), \
74}
75#define DEFINE_IDR(name) struct idr name = IDR_INIT(name)
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77
78#define IDR_NEED_TO_GROW -2
79#define IDR_NOMORE_SPACE -3
80
81#define _idr_rc_to_errno(rc) ((rc) == -1 ? -EAGAIN : -ENOSPC)
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104void *idr_find(struct idr *idp, int id);
105int idr_pre_get(struct idr *idp, gfp_t gfp_mask);
106int idr_get_new(struct idr *idp, void *ptr, int *id);
107int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id);
108int idr_for_each(struct idr *idp,
109 int (*fn)(int id, void *p, void *data), void *data);
110void *idr_get_next(struct idr *idp, int *nextid);
111void *idr_replace(struct idr *idp, void *ptr, int id);
112void idr_remove(struct idr *idp, int id);
113void idr_remove_all(struct idr *idp);
114void idr_destroy(struct idr *idp);
115void idr_init(struct idr *idp);
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124
125#define IDA_CHUNK_SIZE 128
126#define IDA_BITMAP_LONGS (IDA_CHUNK_SIZE / sizeof(long) - 1)
127#define IDA_BITMAP_BITS (IDA_BITMAP_LONGS * sizeof(long) * 8)
128
129struct ida_bitmap {
130 long nr_busy;
131 unsigned long bitmap[IDA_BITMAP_LONGS];
132};
133
134struct ida {
135 struct idr idr;
136 struct ida_bitmap *free_bitmap;
137};
138
139#define IDA_INIT(name) { .idr = IDR_INIT(name), .free_bitmap = NULL, }
140#define DEFINE_IDA(name) struct ida name = IDA_INIT(name)
141
142int ida_pre_get(struct ida *ida, gfp_t gfp_mask);
143int ida_get_new_above(struct ida *ida, int starting_id, int *p_id);
144int ida_get_new(struct ida *ida, int *p_id);
145void ida_remove(struct ida *ida, int id);
146void ida_destroy(struct ida *ida);
147void ida_init(struct ida *ida);
148
149int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
150 gfp_t gfp_mask);
151void ida_simple_remove(struct ida *ida, unsigned int id);
152
153void __init idr_init_cache(void);
154
155#endif
156