1*4882a593Smuzhiyun /* 2*4882a593Smuzhiyun * Copyright (C) 2011 Red Hat, Inc. 3*4882a593Smuzhiyun * 4*4882a593Smuzhiyun * This file is released under the GPL. 5*4882a593Smuzhiyun */ 6*4882a593Smuzhiyun 7*4882a593Smuzhiyun #ifndef DM_SPACE_MAP_METADATA_H 8*4882a593Smuzhiyun #define DM_SPACE_MAP_METADATA_H 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun #include "dm-transaction-manager.h" 11*4882a593Smuzhiyun 12*4882a593Smuzhiyun #define DM_SM_METADATA_BLOCK_SIZE (4096 >> SECTOR_SHIFT) 13*4882a593Smuzhiyun 14*4882a593Smuzhiyun /* 15*4882a593Smuzhiyun * The metadata device is currently limited in size. 16*4882a593Smuzhiyun * 17*4882a593Smuzhiyun * We have one block of index, which can hold 255 index entries. Each 18*4882a593Smuzhiyun * index entry contains allocation info about ~16k metadata blocks. 19*4882a593Smuzhiyun */ 20*4882a593Smuzhiyun #define DM_SM_METADATA_MAX_BLOCKS (255 * ((1 << 14) - 64)) 21*4882a593Smuzhiyun #define DM_SM_METADATA_MAX_SECTORS (DM_SM_METADATA_MAX_BLOCKS * DM_SM_METADATA_BLOCK_SIZE) 22*4882a593Smuzhiyun 23*4882a593Smuzhiyun /* 24*4882a593Smuzhiyun * Unfortunately we have to use two-phase construction due to the cycle 25*4882a593Smuzhiyun * between the tm and sm. 26*4882a593Smuzhiyun */ 27*4882a593Smuzhiyun struct dm_space_map *dm_sm_metadata_init(void); 28*4882a593Smuzhiyun 29*4882a593Smuzhiyun /* 30*4882a593Smuzhiyun * Create a fresh space map. 31*4882a593Smuzhiyun */ 32*4882a593Smuzhiyun int dm_sm_metadata_create(struct dm_space_map *sm, 33*4882a593Smuzhiyun struct dm_transaction_manager *tm, 34*4882a593Smuzhiyun dm_block_t nr_blocks, 35*4882a593Smuzhiyun dm_block_t superblock); 36*4882a593Smuzhiyun 37*4882a593Smuzhiyun /* 38*4882a593Smuzhiyun * Open from a previously-recorded root. 39*4882a593Smuzhiyun */ 40*4882a593Smuzhiyun int dm_sm_metadata_open(struct dm_space_map *sm, 41*4882a593Smuzhiyun struct dm_transaction_manager *tm, 42*4882a593Smuzhiyun void *root_le, size_t len); 43*4882a593Smuzhiyun 44*4882a593Smuzhiyun #endif /* DM_SPACE_MAP_METADATA_H */ 45