dm-space-map-metadata.h
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/*
* Copyright (C) 2011 Red Hat, Inc.
*
* This file is released under the GPL.
*/
#ifndef DM_SPACE_MAP_METADATA_H
#define DM_SPACE_MAP_METADATA_H
#include "dm-transaction-manager.h"
#define DM_SM_METADATA_BLOCK_SIZE (4096 >> SECTOR_SHIFT)
/*
* The metadata device is currently limited in size.
*
* We have one block of index, which can hold 255 index entries. Each
* index entry contains allocation info about ~16k metadata blocks.
*/
#define DM_SM_METADATA_MAX_BLOCKS (255 * ((1 << 14) - 64))
#define DM_SM_METADATA_MAX_SECTORS (DM_SM_METADATA_MAX_BLOCKS * DM_SM_METADATA_BLOCK_SIZE)
/*
* Unfortunately we have to use two-phase construction due to the cycle
* between the tm and sm.
*/
struct dm_space_map *dm_sm_metadata_init(void);
/*
* Create a fresh space map.
*/
int dm_sm_metadata_create(struct dm_space_map *sm,
struct dm_transaction_manager *tm,
dm_block_t nr_blocks,
dm_block_t superblock);
/*
* Open from a previously-recorded root.
*/
int dm_sm_metadata_open(struct dm_space_map *sm,
struct dm_transaction_manager *tm,
void *root_le, size_t len);
#endif /* DM_SPACE_MAP_METADATA_H */