ixethdbportupdate.c

AMCC POWERPC 44X系列的U-BOOT文件

        ixEthDBFreeMacTreeNode(port->updateMethod.searchTree);
    }

    /* forget last used search tree */
    port->updateMethod.searchTree             = NULL;
    port->updateMethod.searchTreePendingWrite = FALSE;

    /* dependending on the update type we do different things */
    if (type == IX_ETH_DB_FILTERING_RECORD || type == IX_ETH_DB_WIFI_RECORD)
    {
        IX_STATUS result;

        FILL_SETMACADDRESSDATABASE_MSG(message, IX_ETH_DB_PORT_ID_TO_NPE_LOGICAL_ID(portID), 
            epDelta, blockCount, 
            IX_OSAL_MMU_VIRT_TO_PHYS(port->updateMethod.npeUpdateZone));

        IX_ETHDB_SEND_NPE_MSG(IX_ETH_DB_PORT_ID_TO_NPE(portID), message, result);

        if (result == IX_SUCCESS)
	{
            IX_ETH_DB_UPDATE_TRACE("DB: (PortUpdate) Finished downloading NPE tree on port %d\n", portID);
        }
        else
        {
            ixEthDBPortInfo[portID].agingEnabled                = FALSE;
            ixEthDBPortInfo[portID].updateMethod.updateEnabled  = FALSE;
            ixEthDBPortInfo[portID].updateMethod.userControlled = TRUE;

            ERROR_LOG("EthDB: (PortUpdate) disabling aging and updates on port %d (assumed dead)\n", portID);

            ixEthDBDatabaseClear(portID, IX_ETH_DB_ALL_RECORD_TYPES);

            return IX_ETH_DB_FAIL;
        }

	return IX_ETH_DB_SUCCESS;
    }
    else if (type == IX_ETH_DB_FIREWALL_RECORD)
    {
        return ixEthDBFirewallUpdate(portID, port->updateMethod.npeUpdateZone, epDelta);
    }
    
    return IX_ETH_DB_INVALID_ARG;
}

/**
 * @brief queries the database for a set of records to be inserted into a given tree
 *
 * @param searchTree pointer to a tree where insertions will be performed; can be NULL
 * @param query set of ports that a database record must match to be inserted into the tree
 *
 * The query method browses through the database, extracts all the descriptors matching
 * the given query parameter and inserts them into the given learning tree.
 * Note that this is an append procedure, the given tree needs not to be empty.
 * A "descriptor matching the query" is a descriptor whose port id is in the query map.
 * If the given tree is empty (NULL) a new tree is created and returned.
 * 
 * @return the tree root
 *
 * @internal
 */
IX_ETH_DB_PUBLIC
MacTreeNode* ixEthDBQuery(MacTreeNode *searchTree, IxEthDBPortMap query, IxEthDBRecordType recordFilter, UINT32 maxEntries)
{
    HashIterator iterator;
    UINT32 entryCount = 0;

    /* browse database */
    BUSY_RETRY(ixEthDBInitHashIterator(&dbHashtable, &iterator));

    while (IS_ITERATOR_VALID(&iterator))
    {
        MacDescriptor *descriptor = (MacDescriptor *) iterator.node->data;

        IX_ETH_DB_UPDATE_TRACE("DB: (PortUpdate) querying [%s]:%d on port map ... ", 
            mac2string(descriptor->macAddress), 
            descriptor->portID);

	if ((descriptor->type & recordFilter) != 0 
            && IS_PORT_INCLUDED(descriptor->portID, query))
	{
            MacDescriptor *descriptorClone = ixEthDBCloneMacDescriptor(descriptor);

            IX_ETH_DB_UPDATE_TRACE("match\n");

            if (descriptorClone != NULL)
            {
                /* add descriptor to tree */
                searchTree = ixEthDBTreeInsert(searchTree, descriptorClone);

                entryCount++;
            }
        }
        else
        {
            IX_ETH_DB_UPDATE_TRACE("no match\n");
        }

        if (entryCount < maxEntries)
        {
            /* advance to the next record */
	        BUSY_RETRY(ixEthDBIncrementHashIterator(&dbHashtable, &iterator));
        }
        else
        {
            /* the NPE won't accept more entries so we can stop now */
            ixEthDBReleaseHashIterator(&iterator);

            IX_ETH_DB_UPDATE_TRACE("DB: (PortUpdate) number of elements reached maximum supported by port\n");

            break;
        }
    }

    IX_ETH_DB_UPDATE_TRACE("DB: (PortUpdate) query inserted %d records in the search tree\n", entryCount);

    return ixEthDBTreeRebalance(searchTree);
}

/**
 * @brief inserts a mac descriptor into an tree
 *
 * @param searchTree tree where the insertion is to be performed (may be NULL)
 * @param descriptor descriptor to insert into tree
 *
 * @return the tree root
 *
 * @internal
 */
IX_ETH_DB_PRIVATE
MacTreeNode* ixEthDBTreeInsert(MacTreeNode *searchTree, MacDescriptor *descriptor)
{
    MacTreeNode *currentNode    = searchTree;
    MacTreeNode *insertLocation = NULL;
    MacTreeNode *newNode;
    INT32 insertPosition = RIGHT;

    if (descriptor == NULL)
    {
        return searchTree;
    }

    /* create a new node */
    newNode = ixEthDBAllocMacTreeNode();

    if (newNode == NULL)
    {
        /* out of memory */
        ERROR_LOG("Warning: ixEthDBAllocMacTreeNode returned NULL in file %s:%d (out of memory?)\n", __FILE__, __LINE__);

        ixEthDBFreeMacDescriptor(descriptor);

        return NULL;
    }

    /* populate node */
    newNode->descriptor = descriptor;

    /* an empty initial tree is a special case */
    if (searchTree == NULL)
    {
        return newNode;
    }

    /* get insertion location */
    while (insertLocation == NULL)
    {
        MacTreeNode *nextNode;

        /* compare given key with current node key */
        insertPosition = ixEthDBAddressCompare(descriptor->macAddress, currentNode->descriptor->macAddress);

        /* navigate down */
        if (insertPosition == RIGHT)
        {
            nextNode = currentNode->right;
        }
        else if (insertPosition == LEFT)
        {
            nextNode = currentNode->left;
        }
        else
        {
            /* error, duplicate key */
            ERROR_LOG("Warning: trapped insertion of a duplicate MAC address in an NPE search tree\n");

            /* this will free the MAC descriptor as well */
            ixEthDBFreeMacTreeNode(newNode);

            return searchTree;
        }

        /* when we can no longer dive through the tree we found the insertion place */
        if (nextNode != NULL)
        {
            currentNode = nextNode;
        }
        else
        {
            insertLocation = currentNode;
        }
    }

    /* insert node */
    if (insertPosition == RIGHT)
    {
        insertLocation->right = newNode;
    }
    else
    {
        insertLocation->left = newNode;
    }

    return searchTree;
}

/**
 * @brief balance a tree
 *
 * @param searchTree tree to balance
 *
 * Converts a tree into a balanced tree and returns the root of
 * the balanced tree. The resulting tree is <i>route balanced</i>
 * not <i>perfectly balanced</i>. This makes no difference to the
 * average tree search time which is the same in both cases, O(log2(n)).
 *
 * @return root of the balanced tree or NULL if there's no memory left
 *
 * @internal
 */
IX_ETH_DB_PRIVATE
MacTreeNode* ixEthDBTreeRebalance(MacTreeNode *searchTree)
{
    MacTreeNode *pseudoRoot = ixEthDBAllocMacTreeNode();
    UINT32 size;

    if (pseudoRoot == NULL)
    {
        /* out of memory */
        return NULL;
    }

    pseudoRoot->right = searchTree;

    ixEthDBRebalanceTreeToVine(pseudoRoot, &size);
    ixEthDBRebalanceVineToTree(pseudoRoot, size);

    searchTree = pseudoRoot->right;

    /* remove pseudoRoot right branch, otherwise it will free the entire tree */
    pseudoRoot->right = NULL;

    ixEthDBFreeMacTreeNode(pseudoRoot);

    return searchTree;
}

/**
 * @brief converts a tree into a vine
 *
 * @param root root of tree to convert
 * @param size depth of vine (equal to the number of nodes in the tree)
 *
 * @internal
 */
IX_ETH_DB_PRIVATE
void ixEthDBRebalanceTreeToVine(MacTreeNode *root, UINT32 *size)
{
    MacTreeNode *vineTail  = root;
    MacTreeNode *remainder = vineTail->right;
    MacTreeNode *tempPtr;

    *size = 0;

    while (remainder != NULL)
    {
        if (remainder->left == NULL)
        {
            /* move tail down one */
            vineTail  = remainder;
            remainder = remainder->right;
            (*size)++;
        }
        else
        {
            /* rotate around remainder */
            tempPtr         = remainder->left;
            remainder->left = tempPtr->right;
            tempPtr->right  = remainder;
            remainder       = tempPtr;
            vineTail->right = tempPtr;
        }
    }
}

/**
 * @brief converts a vine into a balanced tree
 *
 * @param root vine to convert
 * @param size depth of vine
 *
 * @internal
 */
IX_ETH_DB_PRIVATE
void ixEthDBRebalanceVineToTree(MacTreeNode *root, UINT32 size)
{
    UINT32 leafCount = size + 1 - (1 << ixEthDBRebalanceLog2Floor(size + 1));

    ixEthDBRebalanceCompression(root, leafCount);

    size = size - leafCount;

    while (size > 1)
    {
        ixEthDBRebalanceCompression(root, size / 2);

        size /= 2;
    }
}

/**
 * @brief compresses a vine/tree stage into a more balanced vine/tree
 *
 * @param root root of the tree to compress
 * @param count number of "spine" nodes
 *
 * @internal
 */
IX_ETH_DB_PRIVATE
void ixEthDBRebalanceCompression(MacTreeNode *root, UINT32 count)
{
    MacTreeNode *scanner = root;
    MacTreeNode *child;
    UINT32 local_index;

    for (local_index = 0 ; local_index < count ; local_index++)
    {
        child          = scanner->right;
        scanner->right = child->right;
        scanner        = scanner->right;
        child->right   = scanner->left;
        scanner->left  = child;
    }
}

/**
 * @brief computes |_log2(x)_| (a.k.a. floor(log2(x)))
 *
 * @param x number to compute |_log2(x)_| for
 *
 * @return |_log2(x)_|
 *
 * @internal
 */
IX_ETH_DB_PRIVATE
UINT32 ixEthDBRebalanceLog2Floor(UINT32 x)
{
    UINT32 log = 0;
    UINT32 val = 1;

    while (val < x)
    {
        log++;
        val <<= 1;
    }

    return val == x ? log : log - 1;
}