2 * net/tipc/ref.h: Include file for TIPC object registry code
4 * Copyright (c) 2003-2005, Ericsson Research Canada
5 * Copyright (c) 2005, Wind River Systems
6 * Copyright (c) 2005-2006, Ericsson AB
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38 * struct reference - TIPC object reference entry
39 * @object: pointer to object associated with reference entry
40 * @lock: spinlock controlling access to object
41 * @data: reference value associated with object (or link to next unused entry)
54 * struct ref_table - table of TIPC object reference entries
55 * @entries: pointer to array of reference entries
56 * @index_mask: bitmask for array index portion of reference values
57 * @first_free: array index of first unused object reference entry
58 * @last_free: array index of last unused object reference entry
62 struct reference *entries;
68 extern struct ref_table ref_table;
70 int ref_table_init(u32 requested_size, u32 start);
71 void ref_table_stop(void);
73 u32 ref_acquire(void *object, spinlock_t **lock);
74 void ref_discard(u32 ref);
78 * ref_lock - lock referenced object and return pointer to it
81 static inline void *ref_lock(u32 ref)
83 if (likely(ref_table.entries)) {
85 &ref_table.entries[ref & ref_table.index_mask];
87 spin_lock_bh(&r->lock);
88 if (likely(r->data.reference == ref))
90 spin_unlock_bh(&r->lock);
96 * ref_unlock - unlock referenced object
99 static inline void ref_unlock(u32 ref)
101 if (likely(ref_table.entries)) {
102 struct reference *r =
103 &ref_table.entries[ref & ref_table.index_mask];
105 if (likely(r->data.reference == ref))
106 spin_unlock_bh(&r->lock);
108 err("ref_unlock() invoked using obsolete reference\n");
113 * ref_deref - return pointer referenced object (without locking it)
116 static inline void *ref_deref(u32 ref)
118 if (likely(ref_table.entries)) {
119 struct reference *r =
120 &ref_table.entries[ref & ref_table.index_mask];
122 if (likely(r->data.reference == ref))