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diff --git a/cpu/ixp/npe/IxEthDBHashtable.c b/cpu/ixp/npe/IxEthDBHashtable.c
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+/**
+ * @file ethHash.c
+ *
+ * @brief Hashtable implementation
+ *
+ * @par
+ * IXP400 SW Release version 2.0
+ *
+ * -- Copyright Notice --
+ *
+ * @par
+ * Copyright 2001-2005, Intel Corporation.
+ * All rights reserved.
+ *
+ * @par
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Intel Corporation nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * @par
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @par
+ * -- End of Copyright Notice --
+ */
+
+
+#include "IxEthDB_p.h"
+#include "IxEthDBLocks_p.h"
+
+/**
+ * @addtogroup EthDB
+ *
+ * @{
+ */
+
+/**
+ * @brief initializes a hash table object
+ *
+ * @param hashTable uninitialized hash table structure
+ * @param numBuckets number of buckets to use
+ * @param entryHashFunction hash function used
+ * to hash entire hash node data block (for adding)
+ * @param matchFunctions array of match functions, indexed on type,
+ * used to differentiate records with the same hash value
+ * @param freeFunction function used to free node data blocks
+ *
+ * Initializes the given hash table object.
+ *
+ * @internal
+ */
+void ixEthDBInitHash(HashTable *hashTable,
+ UINT32 numBuckets,
+ HashFunction entryHashFunction,
+ MatchFunction *matchFunctions,
+ FreeFunction freeFunction)
+{
+ UINT32 bucketIndex;
+ UINT32 hashSize = numBuckets * sizeof(HashNode *);
+
+ /* entry hashing, matching and freeing methods */
+ hashTable->entryHashFunction = entryHashFunction;
+ hashTable->matchFunctions = matchFunctions;
+ hashTable->freeFunction = freeFunction;
+
+ /* buckets */
+ hashTable->numBuckets = numBuckets;
+
+ /* set to 0 all buckets */
+ memset(hashTable->hashBuckets, 0, hashSize);
+
+ /* init bucket locks - note that initially all mutexes are unlocked after MutexInit()*/
+ for (bucketIndex = 0 ; bucketIndex < numBuckets ; bucketIndex++)
+ {
+ ixOsalFastMutexInit(&hashTable->bucketLocks[bucketIndex]);
+ }
+}
+
+/**
+ * @brief adds an entry to the hash table
+ *
+ * @param hashTable hash table to add the entry to
+ * @param entry entry to add
+ *
+ * The entry will be hashed using the entry hashing function and added to the
+ * hash table, unless a locking blockage occurs, in which case the caller
+ * should retry.
+ *
+ * @retval IX_ETH_DB_SUCCESS if adding <i>entry</i> has succeeded
+ * @retval IX_ETH_DB_NOMEM if there's no memory left in the hash node pool
+ * @retval IX_ETH_DB_BUSY if there's a locking failure on the insertion path
+ *
+ * @internal
+ */
+IX_ETH_DB_PUBLIC IxEthDBStatus ixEthDBAddHashEntry(HashTable *hashTable, void *entry)
+{
+ UINT32 hashValue = hashTable->entryHashFunction(entry);
+ UINT32 bucketIndex = hashValue % hashTable->numBuckets;
+ HashNode *bucket = hashTable->hashBuckets[bucketIndex];
+ HashNode *newNode;
+
+ LockStack locks;
+
+ INIT_STACK(&locks);
+
+ /* lock bucket */
+ PUSH_LOCK(&locks, &hashTable->bucketLocks[bucketIndex]);
+
+ /* lock insertion element (first in chain), if any */
+ if (bucket != NULL)
+ {
+ PUSH_LOCK(&locks, &bucket->lock);
+ }
+
+ /* get new node */
+ newNode = ixEthDBAllocHashNode();
+
+ if (newNode == NULL)
+ {
+ /* unlock everything */
+ UNROLL_STACK(&locks);
+
+ return IX_ETH_DB_NOMEM;
+ }
+
+ /* init lock - note that mutexes are unlocked after MutexInit */
+ ixOsalFastMutexInit(&newNode->lock);
+
+ /* populate new link */
+ newNode->data = entry;
+
+ /* add to bucket */
+ newNode->next = bucket;
+ hashTable->hashBuckets[bucketIndex] = newNode;
+
+ /* unlock bucket and insertion point */
+ UNROLL_STACK(&locks);
+
+ return IX_ETH_DB_SUCCESS;
+}
+
+/**
+ * @brief removes an entry from the hashtable
+ *
+ * @param hashTable hash table to remove entry from
+ * @param keyType type of record key used for matching
+ * @param reference reference key used to identify the entry
+ *
+ * The reference key will be hashed using the key hashing function,
+ * the entry is searched using the hashed value and then examined
+ * against the reference entry using the match function. A positive
+ * match will trigger the deletion of the entry.
+ * Locking failures are reported and the caller should retry.
+ *
+ * @retval IX_ETH_DB_SUCCESS if the removal was successful
+ * @retval IX_ETH_DB_NO_SUCH_ADDR if the entry was not found
+ * @retval IX_ETH_DB_BUSY if a locking failure occured during the process
+ *
+ * @internal
+ */
+IxEthDBStatus ixEthDBRemoveHashEntry(HashTable *hashTable, int keyType, void *reference)
+{
+ UINT32 hashValue = hashTable->entryHashFunction(reference);
+ UINT32 bucketIndex = hashValue % hashTable->numBuckets;
+ HashNode *node = hashTable->hashBuckets[bucketIndex];
+ HashNode *previousNode = NULL;
+
+ LockStack locks;
+
+ INIT_STACK(&locks);
+
+ while (node != NULL)
+ {
+ /* try to lock node */
+ PUSH_LOCK(&locks, &node->lock);
+
+ if (hashTable->matchFunctions[keyType](reference, node->data))
+ {
+ /* found entry */
+ if (node->next != NULL)
+ {
+ PUSH_LOCK(&locks, &node->next->lock);
+ }
+
+ if (previousNode == NULL)
+ {
+ /* node is head of chain */
+ PUSH_LOCK(&locks, &hashTable->bucketLocks[bucketIndex]);
+
+ hashTable->hashBuckets[bucketIndex] = node->next;
+
+ POP_LOCK(&locks);
+ }
+ else
+ {
+ /* relink */
+ previousNode->next = node->next;
+ }
+
+ UNROLL_STACK(&locks);
+
+ /* free node */
+ hashTable->freeFunction(node->data);
+ ixEthDBFreeHashNode(node);
+
+ return IX_ETH_DB_SUCCESS;
+ }
+ else
+ {
+ if (previousNode != NULL)
+ {
+ /* unlock previous node */
+ SHIFT_STACK(&locks);
+ }
+
+ /* advance to next element in chain */
+ previousNode = node;
+ node = node->next;
+ }
+ }
+
+ UNROLL_STACK(&locks);
+
+ /* not found */
+ return IX_ETH_DB_NO_SUCH_ADDR;
+}
+
+/**
+ * @brief retrieves an entry from the hash table
+ *
+ * @param hashTable hash table to perform the search into
+ * @param reference search key (a MAC address)
+ * @param keyType type of record key used for matching
+ * @param searchResult pointer where a reference to the located hash node
+ * is placed
+ *
+ * Searches the entry with the same key as <i>reference</i> and places the
+ * pointer to the resulting node in <i>searchResult</i>.
+ * An implicit write access lock is granted after a search, which gives the
+ * caller the opportunity to modify the entry.
+ * Access should be released as soon as possible using @ref ixEthDBReleaseHashNode().
+ *
+ * @see ixEthDBReleaseHashNode()
+ *
+ * @retval IX_ETH_DB_SUCCESS if the search was completed successfully
+ * @retval IX_ETH_DB_NO_SUCH_ADDRESS if no entry with the given key was found
+ * @retval IX_ETH_DB_BUSY if a locking failure has occured, in which case
+ * the caller should retry
+ *
+ * @warning unless the return value is <b>IX_ETH_DB_SUCCESS</b> the searchResult
+ * location is NOT modified and therefore using a NULL comparison test when the
+ * value was not properly initialized would be an error
+ *
+ * @internal
+ */
+IxEthDBStatus ixEthDBSearchHashEntry(HashTable *hashTable, int keyType, void *reference, HashNode **searchResult)
+{
+ UINT32 hashValue;
+ HashNode *node;
+
+ hashValue = hashTable->entryHashFunction(reference);
+ node = hashTable->hashBuckets[hashValue % hashTable->numBuckets];
+
+ while (node != NULL)
+ {
+ TRY_LOCK(&node->lock);
+
+ if (hashTable->matchFunctions[keyType](reference, node->data))
+ {
+ *searchResult = node;
+
+ return IX_ETH_DB_SUCCESS;
+ }
+ else
+ {
+ UNLOCK(&node->lock);
+
+ node = node->next;
+ }
+ }
+
+ /* not found */
+ return IX_ETH_DB_NO_SUCH_ADDR;
+}
+
+/**
+ * @brief reports the existence of an entry in the hash table
+ *
+ * @param hashTable hash table to perform the search into
+ * @param reference search key (a MAC address)
+ * @param keyType type of record key used for matching
+ *
+ * Searches the entry with the same key as <i>reference</i>.
+ * No implicit write access lock is granted after a search, hence the
+ * caller cannot access or modify the entry. The result is only temporary.
+ *
+ * @see ixEthDBReleaseHashNode()
+ *
+ * @retval IX_ETH_DB_SUCCESS if the search was completed successfully
+ * @retval IX_ETH_DB_NO_SUCH_ADDRESS if no entry with the given key was found
+ * @retval IX_ETH_DB_BUSY if a locking failure has occured, in which case
+ * the caller should retry
+ *
+ * @internal
+ */
+IxEthDBStatus ixEthDBPeekHashEntry(HashTable *hashTable, int keyType, void *reference)
+{
+ UINT32 hashValue;
+ HashNode *node;
+
+ hashValue = hashTable->entryHashFunction(reference);
+ node = hashTable->hashBuckets[hashValue % hashTable->numBuckets];
+
+ while (node != NULL)
+ {
+ TRY_LOCK(&node->lock);
+
+ if (hashTable->matchFunctions[keyType](reference, node->data))
+ {
+ UNLOCK(&node->lock);
+
+ return IX_ETH_DB_SUCCESS;
+ }
+ else
+ {
+ UNLOCK(&node->lock);
+
+ node = node->next;
+ }
+ }
+
+ /* not found */
+ return IX_ETH_DB_NO_SUCH_ADDR;
+}
+
+/**
+ * @brief releases the write access lock
+ *
+ * @pre the node should have been obtained via @ref ixEthDBSearchHashEntry()
+ *
+ * @see ixEthDBSearchHashEntry()
+ *
+ * @internal
+ */
+void ixEthDBReleaseHashNode(HashNode *node)
+{
+ UNLOCK(&node->lock);
+}
+
+/**
+ * @brief initializes a hash iterator
+ *
+ * @param hashTable hash table to be iterated
+ * @param iterator iterator object
+ *
+ * If the initialization is successful the iterator will point to the
+ * first hash table record (if any).
+ * Testing if the iterator has not passed the end of the table should be
+ * done using the IS_ITERATOR_VALID(iteratorPtr) macro.
+ * An implicit write access lock is granted on the entry pointed by the iterator.
+ * The access is automatically revoked when the iterator is incremented.
+ * If the caller decides to terminate the iteration before the end of the table is
+ * passed then the manual access release method, @ref ixEthDBReleaseHashIterator,
+ * must be called.
+ *
+ * @see ixEthDBReleaseHashIterator()
+ *
+ * @retval IX_ETH_DB_SUCCESS if initialization was successful and the iterator points
+ * to the first valid table node
+ * @retval IX_ETH_DB_FAIL if the table is empty
+ * @retval IX_ETH_DB_BUSY if a locking failure has occured, in which case the caller
+ * should retry
+ *
+ * @warning do not use ixEthDBReleaseHashNode() on entries pointed by the iterator, as this
+ * might place the database in a permanent invalid lock state
+ *
+ * @internal
+ */
+IxEthDBStatus ixEthDBInitHashIterator(HashTable *hashTable, HashIterator *iterator)
+{
+ iterator->bucketIndex = 0;
+ iterator->node = NULL;
+ iterator->previousNode = NULL;
+
+ return ixEthDBIncrementHashIterator(hashTable, iterator);
+}
+
+/**
+ * @brief releases the write access locks of the iterator nodes
+ *
+ * @warning use of this function is required only when the caller terminates an iteration
+ * before reaching the end of the table
+ *
+ * @see ixEthDBInitHashIterator()
+ * @see ixEthDBIncrementHashIterator()
+ *
+ * @param iterator iterator whose node(s) should be unlocked
+ *
+ * @internal
+ */
+void ixEthDBReleaseHashIterator(HashIterator *iterator)
+{
+ if (iterator->previousNode != NULL)
+ {
+ UNLOCK(&iterator->previousNode->lock);
+ }
+
+ if (iterator->node != NULL)
+ {
+ UNLOCK(&iterator->node->lock);
+ }
+}
+
+/**
+ * @brief incremenents an iterator so that it points to the next valid entry of the table
+ * (if any)
+ *
+ * @param hashTable hash table to iterate
+ * @param iterator iterator object
+ *
+ * @pre the iterator object must be initialized using @ref ixEthDBInitHashIterator()
+ *
+ * If the increment operation is successful the iterator will point to the
+ * next hash table record (if any).
+ * Testing if the iterator has not passed the end of the table should be
+ * done using the IS_ITERATOR_VALID(iteratorPtr) macro.
+ * An implicit write access lock is granted on the entry pointed by the iterator.
+ * The access is automatically revoked when the iterator is re-incremented.
+ * If the caller decides to terminate the iteration before the end of the table is
+ * passed then the manual access release method, @ref ixEthDBReleaseHashIterator,
+ * must be called.
+ * Is is guaranteed that no other thread can remove or change the iterated entry until
+ * the iterator is incremented successfully.
+ *
+ * @see ixEthDBReleaseHashIterator()
+ *
+ * @retval IX_ETH_DB_SUCCESS if the operation was successful and the iterator points
+ * to the next valid table node
+ * @retval IX_ETH_DB_FAIL if the iterator has passed the end of the table
+ * @retval IX_ETH_DB_BUSY if a locking failure has occured, in which case the caller
+ * should retry
+ *
+ * @warning do not use ixEthDBReleaseHashNode() on entries pointed by the iterator, as this
+ * might place the database in a permanent invalid lock state
+ *
+ * @internal
+ */
+IxEthDBStatus ixEthDBIncrementHashIterator(HashTable *hashTable, HashIterator *iterator)
+{
+ /* unless iterator is just initialized... */
+ if (iterator->node != NULL)
+ {
+ /* try next in chain */
+ if (iterator->node->next != NULL)
+ {
+ TRY_LOCK(&iterator->node->next->lock);
+
+ if (iterator->previousNode != NULL)
+ {
+ UNLOCK(&iterator->previousNode->lock);
+ }
+
+ iterator->previousNode = iterator->node;
+ iterator->node = iterator->node->next;
+
+ return IX_ETH_DB_SUCCESS;
+ }
+ else
+ {
+ /* last in chain, prepare for next bucket */
+ iterator->bucketIndex++;
+ }
+ }
+
+ /* try next used bucket */
+ for (; iterator->bucketIndex < hashTable->numBuckets ; iterator->bucketIndex++)
+ {
+ HashNode **nodePtr = &(hashTable->hashBuckets[iterator->bucketIndex]);
+ HashNode *node = *nodePtr;
+#if (CPU!=SIMSPARCSOLARIS) && !defined (__wince)
+ if (((iterator->bucketIndex & IX_ETHDB_BUCKET_INDEX_MASK) == 0) &&
+ (iterator->bucketIndex < (hashTable->numBuckets - IX_ETHDB_BUCKETPTR_AHEAD)))
+ {
+ /* preload next cache line (2 cache line ahead) */
+ nodePtr += IX_ETHDB_BUCKETPTR_AHEAD;
+ __asm__ ("pld [%0];\n": : "r" (nodePtr));
+ }
+#endif
+ if (node != NULL)
+ {
+ TRY_LOCK(&node->lock);
+
+ /* unlock last one or two nodes in the previous chain */
+ if (iterator->node != NULL)
+ {
+ UNLOCK(&iterator->node->lock);
+
+ if (iterator->previousNode != NULL)
+ {
+ UNLOCK(&iterator->previousNode->lock);
+ }
+ }
+
+ /* redirect iterator */
+ iterator->previousNode = NULL;
+ iterator->node = node;
+
+ return IX_ETH_DB_SUCCESS;
+ }
+ }
+
+ /* could not advance iterator */
+ if (iterator->node != NULL)
+ {
+ UNLOCK(&iterator->node->lock);
+
+ if (iterator->previousNode != NULL)
+ {
+ UNLOCK(&iterator->previousNode->lock);
+ }
+
+ iterator->node = NULL;
+ }
+
+ return IX_ETH_DB_END;
+}
+
+/**
+ * @brief removes an entry pointed by an iterator
+ *
+ * @param hashTable iterated hash table
+ * @param iterator iterator object
+ *
+ * Removes the entry currently pointed by the iterator and repositions the iterator
+ * on the next valid entry (if any). Handles locking issues automatically and
+ * implicitely grants write access lock to the new pointed entry.
+ * Failures due to concurrent threads having write access locks in the same region
+ * preserve the state of the database and the iterator object, leaving the caller
+ * free to retry without loss of access. It is guaranteed that only the thread owning
+ * the iterator can remove the object pointed by the iterator.
+ *
+ * @retval IX_ETH_DB_SUCCESS if removal has succeeded
+ * @retval IX_ETH_DB_BUSY if a locking failure has occured, in which case the caller
+ * should retry
+ *
+ * @internal
+ */
+IxEthDBStatus ixEthDBRemoveEntryAtHashIterator(HashTable *hashTable, HashIterator *iterator)
+{
+ HashIterator nextIteratorPos;
+ LockStack locks;
+
+ INIT_STACK(&locks);
+
+ /* set initial bucket index for next position */
+ nextIteratorPos.bucketIndex = iterator->bucketIndex;
+
+ /* compute iterator position before removing anything and lock ahead */
+ if (iterator->node->next != NULL)
+ {
+ PUSH_LOCK(&locks, &iterator->node->next->lock);
+
+ /* reposition on the next node in the chain */
+ nextIteratorPos.node = iterator->node->next;
+ nextIteratorPos.previousNode = iterator->previousNode;
+ }
+ else
+ {
+ /* try next chain - don't know yet if we'll find anything */
+ nextIteratorPos.node = NULL;
+
+ /* if we find something it's a chain head */
+ nextIteratorPos.previousNode = NULL;
+
+ /* browse up in the buckets to find a non-null chain */
+ while (++nextIteratorPos.bucketIndex < hashTable->numBuckets)
+ {
+ nextIteratorPos.node = hashTable->hashBuckets[nextIteratorPos.bucketIndex];
+
+ if (nextIteratorPos.node != NULL)
+ {
+ /* found a non-empty chain, try to lock head */
+ PUSH_LOCK(&locks, &nextIteratorPos.node->lock);
+
+ break;
+ }
+ }
+ }
+
+ /* restore links over the to-be-deleted item */
+ if (iterator->previousNode == NULL)
+ {
+ /* first in chain, lock bucket */
+ PUSH_LOCK(&locks, &hashTable->bucketLocks[iterator->bucketIndex]);
+
+ hashTable->hashBuckets[iterator->bucketIndex] = iterator->node->next;
+
+ POP_LOCK(&locks);
+ }
+ else
+ {
+ /* relink */
+ iterator->previousNode->next = iterator->node->next;
+
+ /* unlock last remaining node in current chain when moving between chains */
+ if (iterator->node->next == NULL)
+ {
+ UNLOCK(&iterator->previousNode->lock);
+ }
+ }
+
+ /* delete entry */
+ hashTable->freeFunction(iterator->node->data);
+ ixEthDBFreeHashNode(iterator->node);
+
+ /* reposition iterator */
+ *iterator = nextIteratorPos;
+
+ return IX_ETH_DB_SUCCESS;
+}
+
+/**
+ * @}
+ */