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diff --git a/cpu/ixp/npe/IxEthDBPortUpdate.c b/cpu/ixp/npe/IxEthDBPortUpdate.c
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+/**
+ * @file IxEthDBDBPortUpdate.c
+ *
+ * @brief Implementation of dependency and port update handling
+ *
+ * @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"
+
+/* forward prototype declarations */
+IX_ETH_DB_PRIVATE MacTreeNode* ixEthDBTreeInsert(MacTreeNode *searchTree, MacDescriptor *descriptor);
+IX_ETH_DB_PRIVATE void ixEthDBCreateTrees(IxEthDBPortMap updatePorts);
+IX_ETH_DB_PRIVATE MacTreeNode* ixEthDBTreeRebalance(MacTreeNode *searchTree);
+IX_ETH_DB_PRIVATE void ixEthDBRebalanceTreeToVine(MacTreeNode *root, UINT32 *size);
+IX_ETH_DB_PRIVATE void ixEthDBRebalanceVineToTree(MacTreeNode *root, UINT32 size);
+IX_ETH_DB_PRIVATE void ixEthDBRebalanceCompression(MacTreeNode *root, UINT32 count);
+IX_ETH_DB_PRIVATE UINT32 ixEthDBRebalanceLog2Floor(UINT32 x);
+
+extern HashTable dbHashtable;
+
+/**
+ * @brief register types requiring automatic updates
+ *
+ * @param typeArray array indexed on record types, each
+ * element indicating whether the record type requires an
+ * automatic update (TRUE) or not (FALSE)
+ *
+ * Automatic updates are done for registered record types
+ * upon adding, updating (that is, updating the record portID)
+ * and removing records. Whenever an automatic update is triggered
+ * the appropriate ports will be provided with new database
+ * information.
+ *
+ * It is assumed that the typeArray parameter is allocated large
+ * enough to hold all the user defined types. Also, the type
+ * array should be initialized to FALSE as this function only
+ * caters for types which do require automatic updates.
+ *
+ * Note that this function should be called by the component
+ * initialization function.
+ *
+ * @return number of record types registered for automatic
+ * updates
+ *
+ * @internal
+ */
+IX_ETH_DB_PUBLIC
+UINT32 ixEthDBUpdateTypeRegister(BOOL *typeArray)
+{
+ typeArray[IX_ETH_DB_FILTERING_RECORD] = TRUE;
+ typeArray[IX_ETH_DB_FILTERING_VLAN_RECORD] = TRUE;
+
+ return 2;
+}
+
+/**
+ * @brief computes dependencies and triggers port learning tree updates
+ *
+ * @param triggerPorts port map consisting in the ports which triggered the update
+ *
+ * This function browses through all the ports and determines how to waterfall the update
+ * event from the trigger ports to all other ports depending on them.
+ *
+ * Once the list of ports to be updated is determined this function
+ * calls @ref ixEthDBCreateTrees.
+ *
+ * @internal
+ */
+IX_ETH_DB_PUBLIC
+void ixEthDBUpdatePortLearningTrees(IxEthDBPortMap triggerPorts)
+{
+ IxEthDBPortMap updatePorts;
+ UINT32 portIndex;
+
+ ixEthDBUpdateLock();
+
+ SET_EMPTY_DEPENDENCY_MAP(updatePorts);
+
+ for (portIndex = 0 ; portIndex < IX_ETH_DB_NUMBER_OF_PORTS ; portIndex++)
+ {
+ PortInfo *port = &ixEthDBPortInfo[portIndex];
+ BOOL mapsCollide;
+
+ MAPS_COLLIDE(mapsCollide, triggerPorts, port->dependencyPortMap);
+
+ if (mapsCollide /* do triggers influence this port? */
+ && !IS_PORT_INCLUDED(portIndex, updatePorts) /* and it's not already in the update list */
+ && port->updateMethod.updateEnabled) /* and we're allowed to update it */
+ {
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Adding port %d to update set\n", portIndex);
+
+ JOIN_PORT_TO_MAP(updatePorts, portIndex);
+ }
+ else
+ {
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Didn't add port %d to update set, reasons follow:\n", portIndex);
+
+ if (!mapsCollide)
+ {
+ IX_ETH_DB_UPDATE_TRACE("\tMaps don't collide on port %d\n", portIndex);
+ }
+
+ if (IS_PORT_INCLUDED(portIndex, updatePorts))
+ {
+ IX_ETH_DB_UPDATE_TRACE("\tPort %d is already in the update set\n", portIndex);
+ }
+
+ if (!port->updateMethod.updateEnabled)
+ {
+ IX_ETH_DB_UPDATE_TRACE("\tPort %d doesn't have updateEnabled set\n", portIndex);
+ }
+ }
+ }
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Updating port set\n");
+
+ ixEthDBCreateTrees(updatePorts);
+
+ ixEthDBUpdateUnlock();
+}
+
+/**
+ * @brief creates learning trees and calls the port update handlers
+ *
+ * @param updatePorts set of ports in need of learning trees
+ *
+ * This function determines the optimal method of creating learning
+ * trees using a minimal number of database queries, keeping in mind
+ * that different ports can either use the same learning trees or they
+ * can partially share them. The actual tree building routine is
+ * @ref ixEthDBQuery.
+ *
+ * @internal
+ */
+IX_ETH_DB_PRIVATE
+void ixEthDBCreateTrees(IxEthDBPortMap updatePorts)
+{
+ UINT32 portIndex;
+ BOOL result;
+ BOOL portsLeft = TRUE;
+
+ while (portsLeft)
+ {
+ /* get port with minimal dependency map and NULL search tree */
+ UINT32 minPortIndex = MAX_PORT_SIZE;
+ UINT32 minimalSize = MAX_PORT_SIZE;
+
+ for (portIndex = 0 ; portIndex < IX_ETH_DB_NUMBER_OF_PORTS ; portIndex++)
+ {
+ UINT32 size;
+ PortInfo *port = &ixEthDBPortInfo[portIndex];
+
+ /* generate trees only for ports that need them */
+ if (!port->updateMethod.searchTreePendingWrite && IS_PORT_INCLUDED(portIndex, updatePorts))
+ {
+ GET_MAP_SIZE(port->dependencyPortMap, size);
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Dependency map for port %d: size %d\n",
+ portIndex, size);
+
+ if (size < minimalSize)
+ {
+ minPortIndex = portIndex;
+ minimalSize = size;
+ }
+ }
+ else
+ {
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Skipped port %d from tree diff (%s)\n", portIndex,
+ port->updateMethod.searchTreePendingWrite ? "pending write access" : "ignored by query");
+ }
+ }
+
+ /* if a port was found than minimalSize is not MAX_PORT_SIZE */
+ if (minimalSize != MAX_PORT_SIZE)
+ {
+ /* minPortIndex is the port we seek */
+ PortInfo *port = &ixEthDBPortInfo[minPortIndex];
+
+ IxEthDBPortMap query;
+ MacTreeNode *baseTree;
+
+ /* now try to find a port with minimal map difference */
+ PortInfo *minimalDiffPort = NULL;
+ UINT32 minimalDiff = MAX_PORT_SIZE;
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Minimal size port is %d\n", minPortIndex);
+
+ for (portIndex = 0 ; portIndex < IX_ETH_DB_NUMBER_OF_PORTS ; portIndex++)
+ {
+ PortInfo *diffPort = &ixEthDBPortInfo[portIndex];
+ BOOL mapIsSubset;
+
+ IS_MAP_SUBSET(mapIsSubset, diffPort->dependencyPortMap, port->dependencyPortMap);
+
+
+ if (portIndex != minPortIndex
+ && diffPort->updateMethod.searchTree != NULL
+ && mapIsSubset)
+ {
+ /* compute size and pick only minimal size difference */
+ UINT32 diffPortSize;
+ UINT32 sizeDifference;
+
+ GET_MAP_SIZE(diffPort->dependencyPortMap, diffPortSize);
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Checking port %d for differences...\n", portIndex);
+
+ sizeDifference = minimalSize - diffPortSize;
+
+ if (sizeDifference < minimalDiff)
+ {
+ minimalDiffPort = diffPort;
+ minimalDiff = sizeDifference;
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Minimal difference 0x%x was found on port %d\n",
+ minimalDiff, portIndex);
+ }
+ }
+ }
+
+ /* check if filtering is enabled on this port */
+ if ((port->featureStatus & IX_ETH_DB_FILTERING) != 0)
+ {
+ /* if minimalDiff is not MAX_PORT_SIZE minimalDiffPort points to the most similar port */
+ if (minimalDiff != MAX_PORT_SIZE)
+ {
+ baseTree = ixEthDBCloneMacTreeNode(minimalDiffPort->updateMethod.searchTree);
+ DIFF_MAPS(query, port->dependencyPortMap , minimalDiffPort->dependencyPortMap);
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Found minimal diff, extending tree %d on query\n",
+ minimalDiffPort->portID);
+ }
+ else /* .. otherwise no similar port was found, build tree from scratch */
+ {
+ baseTree = NULL;
+
+ COPY_DEPENDENCY_MAP(query, port->dependencyPortMap);
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) No similar diff, creating tree from query\n");
+ }
+
+ IS_EMPTY_DEPENDENCY_MAP(result, query);
+
+ if (!result) /* otherwise we don't need anything more on top of the cloned tree */
+ {
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Adding query tree to port %d\n", minPortIndex);
+
+ /* build learning tree */
+ port->updateMethod.searchTree = ixEthDBQuery(baseTree, query, IX_ETH_DB_ALL_FILTERING_RECORDS, MAX_ELT_SIZE);
+ }
+ else
+ {
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) Query is empty, assuming identical nearest tree\n");
+
+ port->updateMethod.searchTree = baseTree;
+ }
+ }
+ else
+ {
+ /* filtering is not enabled, will download an empty tree */
+ if (port->updateMethod.searchTree != NULL)
+ {
+ ixEthDBFreeMacTreeNode(port->updateMethod.searchTree);
+ }
+
+ port->updateMethod.searchTree = NULL;
+ }
+
+ /* mark tree as valid */
+ port->updateMethod.searchTreePendingWrite = TRUE;
+ }
+ else
+ {
+ portsLeft = FALSE;
+
+ IX_ETH_DB_UPDATE_TRACE("DB: (Update) No trees to create this round\n");
+ }
+ }
+
+ for (portIndex = 0 ; portIndex < IX_ETH_DB_NUMBER_OF_PORTS ; portIndex++)
+ {
+ PortInfo *updatePort = &ixEthDBPortInfo[portIndex];
+
+ if (updatePort->updateMethod.searchTreePendingWrite)
+ {
+ IX_ETH_DB_UPDATE_TRACE("DB: (PortUpdate) Starting procedure to upload new search tree (%snull) into NPE %d\n",
+ updatePort->updateMethod.searchTree != NULL ? "not " : "",
+ portIndex);
+
+ updatePort->updateMethod.updateHandler(portIndex, IX_ETH_DB_FILTERING_RECORD);
+ }
+ }
+}
+
+/**
+ * @brief standard NPE update handler
+ *
+ * @param portID id of the port to be updated
+ * @param type record type to be pushed during this update
+ *
+ * The NPE update handler manages updating the NPE databases
+ * given a certain record type.
+ *
+ * @internal
+ */
+IX_ETH_DB_PUBLIC
+IxEthDBStatus ixEthDBNPEUpdateHandler(IxEthDBPortId portID, IxEthDBRecordType type)
+{
+ UINT32 epDelta, blockCount;
+ IxNpeMhMessage message;
+ UINT32 treeSize = 0;
+ PortInfo *port = &ixEthDBPortInfo[portID];
+
+ /* size selection and type check */
+ if (type == IX_ETH_DB_FILTERING_RECORD || type == IX_ETH_DB_WIFI_RECORD)
+ {
+ treeSize = FULL_ELT_BYTE_SIZE;
+ }
+ else if (type == IX_ETH_DB_FIREWALL_RECORD)
+ {
+ treeSize = FULL_FW_BYTE_SIZE;
+ }
+ else
+ {
+ return IX_ETH_DB_INVALID_ARG;
+ }
+
+ /* serialize tree into memory */
+ ixEthDBNPETreeWrite(type, treeSize, port->updateMethod.npeUpdateZone, port->updateMethod.searchTree, &epDelta, &blockCount);
+
+ /* free internal copy */
+ if (port->updateMethod.searchTree != NULL)
+ {
+ 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;
+}
+