1 /* 2 * Copyright (C) 2011 Red Hat, Inc. 3 * 4 * This file is released under the GPL. 5 */ 6 7 #ifndef DM_SPACE_MAP_METADATA_H 8 #define DM_SPACE_MAP_METADATA_H 9 10 #include "dm-transaction-manager.h" 11 12 #define DM_SM_METADATA_BLOCK_SIZE (4096 >> SECTOR_SHIFT) 13 14 /* 15 * The metadata device is currently limited in size. 16 * 17 * We have one block of index, which can hold 255 index entries. Each 18 * index entry contains allocation info about ~16k metadata blocks. 19 */ 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) 22 23 /* 24 * Unfortunately we have to use two-phase construction due to the cycle 25 * between the tm and sm. 26 */ 27 struct dm_space_map *dm_sm_metadata_init(void); 28 29 /* 30 * Create a fresh space map. 31 */ 32 int dm_sm_metadata_create(struct dm_space_map *sm, 33 struct dm_transaction_manager *tm, 34 dm_block_t nr_blocks, 35 dm_block_t superblock); 36 37 /* 38 * Open from a previously-recorded root. 39 */ 40 int dm_sm_metadata_open(struct dm_space_map *sm, 41 struct dm_transaction_manager *tm, 42 void *root_le, size_t len); 43 44 #endif /* DM_SPACE_MAP_METADATA_H */ 45