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-rw-r--r--net/tipc/ref.h89
1 files changed, 4 insertions, 85 deletions
diff --git a/net/tipc/ref.h b/net/tipc/ref.h
index 38f3a7f4a78d..7e3798ea93b9 100644
--- a/net/tipc/ref.h
+++ b/net/tipc/ref.h
@@ -2,7 +2,7 @@
2 * net/tipc/ref.h: Include file for TIPC object registry code 2 * net/tipc/ref.h: Include file for TIPC object registry code
3 * 3 *
4 * Copyright (c) 1991-2006, Ericsson AB 4 * Copyright (c) 1991-2006, Ericsson AB
5 * Copyright (c) 2005, Wind River Systems 5 * Copyright (c) 2005-2006, Wind River Systems
6 * All rights reserved. 6 * All rights reserved.
7 * 7 *
8 * Redistribution and use in source and binary forms, with or without 8 * Redistribution and use in source and binary forms, with or without
@@ -37,95 +37,14 @@
37#ifndef _TIPC_REF_H 37#ifndef _TIPC_REF_H
38#define _TIPC_REF_H 38#define _TIPC_REF_H
39 39
40/**
41 * struct reference - TIPC object reference entry
42 * @object: pointer to object associated with reference entry
43 * @lock: spinlock controlling access to object
44 * @data: reference value associated with object (or link to next unused entry)
45 */
46
47struct reference {
48 void *object;
49 spinlock_t lock;
50 union {
51 u32 next_plus_upper;
52 u32 reference;
53 } data;
54};
55
56/**
57 * struct tipc_ref_table - table of TIPC object reference entries
58 * @entries: pointer to array of reference entries
59 * @index_mask: bitmask for array index portion of reference values
60 * @first_free: array index of first unused object reference entry
61 * @last_free: array index of last unused object reference entry
62 */
63
64struct ref_table {
65 struct reference *entries;
66 u32 index_mask;
67 u32 first_free;
68 u32 last_free;
69};
70
71extern struct ref_table tipc_ref_table;
72
73int tipc_ref_table_init(u32 requested_size, u32 start); 40int tipc_ref_table_init(u32 requested_size, u32 start);
74void tipc_ref_table_stop(void); 41void tipc_ref_table_stop(void);
75 42
76u32 tipc_ref_acquire(void *object, spinlock_t **lock); 43u32 tipc_ref_acquire(void *object, spinlock_t **lock);
77void tipc_ref_discard(u32 ref); 44void tipc_ref_discard(u32 ref);
78 45
79 46void *tipc_ref_lock(u32 ref);
80/** 47void tipc_ref_unlock(u32 ref);
81 * tipc_ref_lock - lock referenced object and return pointer to it 48void *tipc_ref_deref(u32 ref);
82 */
83
84static inline void *tipc_ref_lock(u32 ref)
85{
86 if (likely(tipc_ref_table.entries)) {
87 struct reference *r =
88 &tipc_ref_table.entries[ref & tipc_ref_table.index_mask];
89
90 spin_lock_bh(&r->lock);
91 if (likely(r->data.reference == ref))
92 return r->object;
93 spin_unlock_bh(&r->lock);
94 }
95 return NULL;
96}
97
98/**
99 * tipc_ref_unlock - unlock referenced object
100 */
101
102static inline void tipc_ref_unlock(u32 ref)
103{
104 if (likely(tipc_ref_table.entries)) {
105 struct reference *r =
106 &tipc_ref_table.entries[ref & tipc_ref_table.index_mask];
107
108 if (likely(r->data.reference == ref))
109 spin_unlock_bh(&r->lock);
110 else
111 err("tipc_ref_unlock() invoked using obsolete reference\n");
112 }
113}
114
115/**
116 * tipc_ref_deref - return pointer referenced object (without locking it)
117 */
118
119static inline void *tipc_ref_deref(u32 ref)
120{
121 if (likely(tipc_ref_table.entries)) {
122 struct reference *r =
123 &tipc_ref_table.entries[ref & tipc_ref_table.index_mask];
124
125 if (likely(r->data.reference == ref))
126 return r->object;
127 }
128 return NULL;
129}
130 49
131#endif 50#endif