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git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - drivers/md/persistent-data/dm-space-map-metadata.h
2 * Copyright (C) 2011 Red Hat, Inc.
4 * This file is released under the GPL.
7 #ifndef DM_SPACE_MAP_METADATA_H
8 #define DM_SPACE_MAP_METADATA_H
10 #include "dm-transaction-manager.h"
12 #define DM_SM_METADATA_BLOCK_SIZE (4096 >> SECTOR_SHIFT)
15 * The metadata device is currently limited in size.
17 * We have one block of index, which can hold 255 index entries. Each
18 * index entry contains allocation info about ~16k metadata blocks.
20 #define DM_SM_METADATA_MAX_BLOCKS (255 * ((1 << 14) - 64))
21 #define DM_SM_METADATA_MAX_SECTORS (DM_SM_METADATA_MAX_BLOCKS * DM_SM_METADATA_BLOCK_SIZE)
24 * Unfortunately we have to use two-phase construction due to the cycle
25 * between the tm and sm.
27 struct dm_space_map
*dm_sm_metadata_init(void);
30 * Create a fresh space map.
32 int dm_sm_metadata_create(struct dm_space_map
*sm
,
33 struct dm_transaction_manager
*tm
,
35 dm_block_t superblock
);
38 * Open from a previously-recorded root.
40 int dm_sm_metadata_open(struct dm_space_map
*sm
,
41 struct dm_transaction_manager
*tm
,
42 void *root_le
, size_t len
);
44 #endif /* DM_SPACE_MAP_METADATA_H */