/*

 * 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/superBlock.h#2 $

 */

#ifndef SUPER_BLOCK_H

#define SUPER_BLOCK_H

#include "buffer.h"

#include "completion.h"

#include "types.h"

typedef struct superBlock SuperBlock;

/**

 * Make a new super block.

 *

 * @param [in]  layer          The layer on which to write this super block

 * @param [out] superBlockPtr  A pointer to hold the new super block

 *

 * @return VDO_SUCCESS or an error

 **/

int makeSuperBlock(PhysicalLayer *layer, SuperBlock **superBlockPtr)

  __attribute__((warn_unused_result));

/**

 * Free a super block and null out the reference to it.

 *

 * @param superBlockPtr the reference to the super block to free

 **/

void freeSuperBlock(SuperBlock **superBlockPtr);

/**

 * Save a super block.

 *

 * @param layer             The physical layer on which to save the super block

 * @param superBlock        The super block to save

 * @param superBlockOffset  The location of the super block

 *

 * @return VDO_SUCCESS or an error

 **/

int saveSuperBlock(PhysicalLayer       *layer,

                   SuperBlock          *superBlock,

                   PhysicalBlockNumber  superBlockOffset)

  __attribute__((warn_unused_result));

/**

 * Save a super block asynchronously.

 *

 * @param superBlock        The super block to save

 * @param superBlockOffset  The location at which to write the super block

 * @param parent            The object to notify when the save is complete

 **/

void saveSuperBlockAsync(SuperBlock          *superBlock,

                         PhysicalBlockNumber  superBlockOffset,

                         VDOCompletion       *parent);

/**

 * Allocate a super block and read its contents from storage.

 *

 * @param [in]  layer             The layer from which to load the super block

 * @param [in]  superBlockOffset  The location from which to read the super

 *                                block

 * @param [out] superBlockPtr     A pointer to hold the loaded super block

 *

 * @return VDO_SUCCESS or an error

 **/

int loadSuperBlock(PhysicalLayer        *layer,

                   PhysicalBlockNumber   superBlockOffset,

                   SuperBlock          **superBlockPtr)

  __attribute__((warn_unused_result));

/**

 * Allocate a super block and read its contents from storage asynchronously. If

 * a load error occurs before the super block's own completion can be allocated,

 * the parent will be finished with the error.

 *

 * @param [in]  parent            The completion to finish after loading the

 *                                super block

 * @param [in]  superBlockOffset  The location from which to read the super

 *                                block

 * @param [out] superBlockPtr     A pointer to hold the super block

 **/

void loadSuperBlockAsync(VDOCompletion        *parent,

                         PhysicalBlockNumber   superBlockOffset,

                         SuperBlock          **superBlockPtr);

/**

 * Get a buffer which contains the component data from a super block.

 *

 * @param superBlock  The super block from which to get the component data

 *

 * @return the component data in a buffer

 **/

Buffer *getComponentBuffer(SuperBlock *superBlock)

  __attribute__((warn_unused_result));

/**

 * Get the release version number that was loaded from the volume when the

 * SuperBlock was decoded.

 *

 * @param superBlock  The super block to query

 *

 * @return the release version number that was decoded from the volume

 **/

ReleaseVersionNumber getLoadedReleaseVersion(const SuperBlock *superBlock)

  __attribute__((warn_unused_result));

/**

 * Get the encoded size of the fixed (non-component data) portion of a super

 * block (this is for unit testing).

 *

 * @return The encoded size of the fixed portion of the super block

 **/

size_t getFixedSuperBlockSize(void)

  __attribute__((warn_unused_result));

#endif /* SUPER_BLOCK_H */