1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * Copyright (C) 2011 Red Hat, Inc. |
4 | * |
5 | * This file is released under the GPL. |
6 | */ |
7 | |
8 | #ifndef DM_SPACE_MAP_METADATA_H |
9 | #define DM_SPACE_MAP_METADATA_H |
10 | |
11 | #include "dm-transaction-manager.h" |
12 | |
13 | #define DM_SM_METADATA_BLOCK_SIZE (4096 >> SECTOR_SHIFT) |
14 | |
15 | /* |
16 | * The metadata device is currently limited in size. |
17 | * |
18 | * We have one block of index, which can hold 255 index entries. Each |
19 | * index entry contains allocation info about ~16k metadata blocks. |
20 | */ |
21 | #define DM_SM_METADATA_MAX_BLOCKS (255 * ((1 << 14) - 64)) |
22 | #define DM_SM_METADATA_MAX_SECTORS (DM_SM_METADATA_MAX_BLOCKS * DM_SM_METADATA_BLOCK_SIZE) |
23 | |
24 | /* |
25 | * Unfortunately we have to use two-phase construction due to the cycle |
26 | * between the tm and sm. |
27 | */ |
28 | struct dm_space_map *dm_sm_metadata_init(void); |
29 | |
30 | /* |
31 | * Create a fresh space map. |
32 | */ |
33 | int dm_sm_metadata_create(struct dm_space_map *sm, |
34 | struct dm_transaction_manager *tm, |
35 | dm_block_t nr_blocks, |
36 | dm_block_t superblock); |
37 | |
38 | /* |
39 | * Open from a previously-recorded root. |
40 | */ |
41 | int dm_sm_metadata_open(struct dm_space_map *sm, |
42 | struct dm_transaction_manager *tm, |
43 | void *root_le, size_t len); |
44 | |
45 | #endif /* DM_SPACE_MAP_METADATA_H */ |
46 | |