/*
* net/tipc/ref.c: TIPC object registry code
*
- * Copyright (c) 2003-2005, Ericsson Research Canada
+ * Copyright (c) 1991-2006, Ericsson AB
* Copyright (c) 2004-2005, Wind River Systems
- * Copyright (c) 2005-2006, Ericsson AB
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* because entry 0's reference field has the form XXXX|1--1.
*/
-struct ref_table ref_table = { 0 };
+struct ref_table tipc_ref_table = { NULL };
-rwlock_t reftbl_lock = RW_LOCK_UNLOCKED;
+static DEFINE_RWLOCK(ref_table_lock);
/**
- * ref_table_init - create reference table for objects
+ * tipc_ref_table_init - create reference table for objects
*/
-int ref_table_init(u32 requested_size, u32 start)
+int tipc_ref_table_init(u32 requested_size, u32 start)
{
struct reference *table;
u32 sz = 1 << 4;
if (table == NULL)
return -ENOMEM;
- write_lock_bh(&reftbl_lock);
+ write_lock_bh(&ref_table_lock);
index_mask = sz - 1;
for (i = sz - 1; i >= 0; i--) {
- table[i].object = 0;
- table[i].lock = SPIN_LOCK_UNLOCKED;
+ table[i].object = NULL;
+ spin_lock_init(&table[i].lock);
table[i].data.next_plus_upper = (start & ~index_mask) + i - 1;
}
- ref_table.entries = table;
- ref_table.index_mask = index_mask;
- ref_table.first_free = sz - 1;
- ref_table.last_free = 1;
- write_unlock_bh(&reftbl_lock);
+ tipc_ref_table.entries = table;
+ tipc_ref_table.index_mask = index_mask;
+ tipc_ref_table.first_free = sz - 1;
+ tipc_ref_table.last_free = 1;
+ write_unlock_bh(&ref_table_lock);
return TIPC_OK;
}
/**
- * ref_table_stop - destroy reference table for objects
+ * tipc_ref_table_stop - destroy reference table for objects
*/
-void ref_table_stop(void)
+void tipc_ref_table_stop(void)
{
- if (!ref_table.entries)
+ if (!tipc_ref_table.entries)
return;
- vfree(ref_table.entries);
- ref_table.entries = 0;
+ vfree(tipc_ref_table.entries);
+ tipc_ref_table.entries = NULL;
}
/**
- * ref_acquire - create reference to an object
+ * tipc_ref_acquire - create reference to an object
*
* Return a unique reference value which can be translated back to the pointer
* 'object' at a later time. Also, pass back a pointer to the lock protecting
* the object, but without locking it.
*/
-u32 ref_acquire(void *object, spinlock_t **lock)
+u32 tipc_ref_acquire(void *object, spinlock_t **lock)
{
struct reference *entry;
u32 index;
u32 next_plus_upper;
u32 reference = 0;
- assert(ref_table.entries && object);
+ if (!object) {
+ err("Attempt to acquire reference to non-existent object\n");
+ return 0;
+ }
+ if (!tipc_ref_table.entries) {
+ err("Reference table not found during acquisition attempt\n");
+ return 0;
+ }
- write_lock_bh(&reftbl_lock);
- if (ref_table.first_free) {
- index = ref_table.first_free;
- entry = &(ref_table.entries[index]);
- index_mask = ref_table.index_mask;
+ write_lock_bh(&ref_table_lock);
+ if (tipc_ref_table.first_free) {
+ index = tipc_ref_table.first_free;
+ entry = &(tipc_ref_table.entries[index]);
+ index_mask = tipc_ref_table.index_mask;
/* take lock in case a previous user of entry still holds it */
spin_lock_bh(&entry->lock);
next_plus_upper = entry->data.next_plus_upper;
- ref_table.first_free = next_plus_upper & index_mask;
+ tipc_ref_table.first_free = next_plus_upper & index_mask;
reference = (next_plus_upper & ~index_mask) + index;
entry->data.reference = reference;
entry->object = object;
*lock = &entry->lock;
spin_unlock_bh(&entry->lock);
}
- write_unlock_bh(&reftbl_lock);
+ write_unlock_bh(&ref_table_lock);
return reference;
}
/**
- * ref_discard - invalidate references to an object
+ * tipc_ref_discard - invalidate references to an object
*
* Disallow future references to an object and free up the entry for re-use.
* Note: The entry's spin_lock may still be busy after discard
*/
-void ref_discard(u32 ref)
+void tipc_ref_discard(u32 ref)
{
struct reference *entry;
u32 index;
u32 index_mask;
- assert(ref_table.entries);
- assert(ref != 0);
+ if (!ref) {
+ err("Attempt to discard reference 0\n");
+ return;
+ }
+ if (!tipc_ref_table.entries) {
+ err("Reference table not found during discard attempt\n");
+ return;
+ }
- write_lock_bh(&reftbl_lock);
- index_mask = ref_table.index_mask;
+ write_lock_bh(&ref_table_lock);
+ index_mask = tipc_ref_table.index_mask;
index = ref & index_mask;
- entry = &(ref_table.entries[index]);
- assert(entry->object != 0);
- assert(entry->data.reference == ref);
+ entry = &(tipc_ref_table.entries[index]);
+
+ if (!entry->object) {
+ err("Attempt to discard reference to non-existent object\n");
+ goto exit;
+ }
+ if (entry->data.reference != ref) {
+ err("Attempt to discard non-existent reference\n");
+ goto exit;
+ }
/* mark entry as unused */
- entry->object = 0;
- if (ref_table.first_free == 0)
- ref_table.first_free = index;
+ entry->object = NULL;
+ if (tipc_ref_table.first_free == 0)
+ tipc_ref_table.first_free = index;
else
/* next_plus_upper is always XXXX|0--0 for last free entry */
- ref_table.entries[ref_table.last_free].data.next_plus_upper
+ tipc_ref_table.entries[tipc_ref_table.last_free].data.next_plus_upper
|= index;
- ref_table.last_free = index;
+ tipc_ref_table.last_free = index;
/* increment upper bits of entry to invalidate subsequent references */
entry->data.next_plus_upper = (ref & ~index_mask) + (index_mask + 1);
- write_unlock_bh(&reftbl_lock);
+exit:
+ write_unlock_bh(&ref_table_lock);
}
projects / powerpc.git / blobdiff