/*

 * Copyright (c) 2020 Red Hat, Inc.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 * 

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

 * 02110-1301, USA. 

 *

 * $Id: //eng/vdo-releases/aluminum/src/c++/vdo/base/logicalZone.h#3 $

 */

#ifndef LOGICAL_ZONE_H

#define LOGICAL_ZONE_H

#include "adminState.h"

#include "intMap.h"

#include "types.h"

/**

 * Get a logical zone by number.

 *

 * @param zones       A set of logical zones

 * @param zoneNumber  The number of the zone to get

 *

 * @return The requested zone

 **/

LogicalZone *getLogicalZone(LogicalZones *zones, ZoneCount zoneNumber)

  __attribute__((warn_unused_result));

/**

 * Create a set of logical zones.

 *

 * @param [in]  vdo       The VDO to which the zones will belong

 * @param [out] zonesPtr  A pointer to hold the new zones

 *

 * @return VDO_SUCCESS or an error code

 **/

int makeLogicalZones(VDO *vdo, LogicalZones **zonesPtr)

  __attribute__((warn_unused_result));

/**

 * Free a set of logical zones and null out the reference to it.

 *

 * @param zonePtr  A pointer to the zone to free

 **/

void freeLogicalZones(LogicalZones **zonePtr);

/**

 * Drain a set of logical zones.

 *

 * @param zones       The logical zones to suspend

 * @param operation   The type of drain to perform

 * @param completion  The object to notify when the zones are suspended

 **/

void drainLogicalZones(LogicalZones   *zones,

                       AdminStateCode  operation,

                       VDOCompletion  *completion);

/**

 * Resume a set of logical zones.

 *

 * @param zones   The logical zones to resume

 * @param parent  The object to notify when the zones have resumed

 **/

void resumeLogicalZones(LogicalZones *zones, VDOCompletion *parent);

/**

 * Get the ID of a logical zone's thread.

 *

 * @param zone  The zone

 *

 * @return The zone's thread ID

 **/

ThreadID getLogicalZoneThreadID(const LogicalZone *zone)

  __attribute__((warn_unused_result));

/**

 * Get the portion of the block map for this zone.

 *

 * @param zone  The zone

 *

 * @return The block map zone

 **/

BlockMapZone *getBlockMapForZone(const LogicalZone *zone)

  __attribute__((warn_unused_result));

/**

 * Get the logical lock map for this zone.

 *

 * @param zone  The zone

 *

 * @return The logical lock map for the zone

 **/

IntMap *getLBNLockMap(const LogicalZone *zone)

  __attribute__((warn_unused_result));

/**

 * Get the next-highest-numbered logical zone, or NULL if the

 * zone is the highest-numbered zone in its VDO.

 *

 * @param zone  The logical zone to query

 *

 * @return The logical zone whose zone number is one greater than the given

 *         zone, or NULL if there is no such zone

 **/

LogicalZone *getNextLogicalZone(const LogicalZone *zone)

  __attribute__((warn_unused_result));

/**

 * Increment the flush generation in a logical zone.

 *

 * @param zone                The logical zone

 * @param expectedGeneration  The expected value of the flush generation

 *                            before the increment

 **/

void incrementFlushGeneration(LogicalZone    *zone,

                              SequenceNumber  expectedGeneration);

/**

 * Get the oldest flush generation which is locked by a logical zone.

 *

 * @param zone   The logical zone

 *

 * @return The oldest generation locked by the zone

 **/

SequenceNumber getOldestLockedGeneration(const LogicalZone *zone)

  __attribute__((warn_unused_result));

/**

 * Acquire the shared lock on a flush generation by a write DataVIO.

 *

 * @param dataVIO   The DataVIO

 *

 * @return VDO_SUCCESS or an error code

 **/

int acquireFlushGenerationLock(DataVIO *dataVIO)

  __attribute__((warn_unused_result));

/**

 * Release the shared lock on a flush generation held by a write DataVIO. If

 * there are pending flushes, and this DataVIO completes the oldest generation

 * active in this zone, an attempt will be made to finish any flushes which may

 * now be complete.

 *

 * @param dataVIO  The DataVIO whose lock is to be released

 **/

void releaseFlushGenerationLock(DataVIO *dataVIO);

/**

 * Get the selector for deciding which physical zone should be allocated from

 * next for activities in a logical zone.

 *

 * @param zone  The logical zone of the operation which needs an allocation

 *

 * @return The allocation selector for this zone

 **/

AllocationSelector *getAllocationSelector(LogicalZone *zone)

  __attribute__((warn_unused_result));

/**

 * Dump information about a logical zone to the log for debugging, in a

 * thread-unsafe fashion.

 *

 * @param zone   The zone to dump

 **/

void dumpLogicalZone(const LogicalZone *zone);

#endif // LOGICAL_ZONE_H