13241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber/* 23241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * Copyright (C) 2011 Red Hat, Inc. 33241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * 43241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * This file is released under the GPL. 53241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber */ 63241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 73241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber#ifndef _LINUX_DM_SPACE_MAP_H 83241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber#define _LINUX_DM_SPACE_MAP_H 93241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 103241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber#include "dm-block-manager.h" 113241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 123241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber/* 133241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * struct dm_space_map keeps a record of how many times each block in a device 143241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * is referenced. It needs to be fixed on disk as part of the transaction. 153241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber */ 163241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstruct dm_space_map { 173241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber void (*destroy)(struct dm_space_map *sm); 183241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 193241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber /* 203241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * You must commit before allocating the newly added space. 213241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber */ 223241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*extend)(struct dm_space_map *sm, dm_block_t extra_blocks); 233241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 243241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber /* 253241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * Extensions do not appear in this count until after commit has 263241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * been called. 273241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber */ 283241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*get_nr_blocks)(struct dm_space_map *sm, dm_block_t *count); 293241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 303241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber /* 313241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * Space maps must never allocate a block from the previous 323241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * transaction, in case we need to rollback. This complicates the 333241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * semantics of get_nr_free(), it should return the number of blocks 343241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * that are available for allocation _now_. For instance you may 353241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * have blocks with a zero reference count that will not be 363241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * available for allocation until after the next commit. 373241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber */ 383241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*get_nr_free)(struct dm_space_map *sm, dm_block_t *count); 393241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 403241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*get_count)(struct dm_space_map *sm, dm_block_t b, uint32_t *result); 413241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*count_is_more_than_one)(struct dm_space_map *sm, dm_block_t b, 423241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int *result); 433241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*set_count)(struct dm_space_map *sm, dm_block_t b, uint32_t count); 443241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 453241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*commit)(struct dm_space_map *sm); 463241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 473241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*inc_block)(struct dm_space_map *sm, dm_block_t b); 483241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*dec_block)(struct dm_space_map *sm, dm_block_t b); 493241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 503241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber /* 513241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * new_block will increment the returned block. 523241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber */ 533241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*new_block)(struct dm_space_map *sm, dm_block_t *b); 543241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 553241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber /* 563241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * The root contains all the information needed to fix the space map. 573241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * Generally this info is small, so squirrel it away in a disk block 583241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber * along with other info. 593241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber */ 603241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*root_size)(struct dm_space_map *sm, size_t *result); 613241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber int (*copy_root)(struct dm_space_map *sm, void *copy_to_here_le, size_t len); 623241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber}; 633241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 643241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber/*----------------------------------------------------------------*/ 653241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 663241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline void dm_sm_destroy(struct dm_space_map *sm) 673241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 683241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber sm->destroy(sm); 693241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 703241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 713241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_extend(struct dm_space_map *sm, dm_block_t extra_blocks) 723241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 733241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->extend(sm, extra_blocks); 743241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 753241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 763241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count) 773241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 783241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->get_nr_blocks(sm, count); 793241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 803241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 813241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_get_nr_free(struct dm_space_map *sm, dm_block_t *count) 823241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 833241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->get_nr_free(sm, count); 843241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 853241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 863241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_get_count(struct dm_space_map *sm, dm_block_t b, 873241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber uint32_t *result) 883241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 893241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->get_count(sm, b, result); 903241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 913241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 923241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_count_is_more_than_one(struct dm_space_map *sm, 933241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber dm_block_t b, int *result) 943241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 953241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->count_is_more_than_one(sm, b, result); 963241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 973241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 983241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_set_count(struct dm_space_map *sm, dm_block_t b, 993241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber uint32_t count) 1003241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 1013241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->set_count(sm, b, count); 1023241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 1033241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 1043241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_commit(struct dm_space_map *sm) 1053241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 1063241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->commit(sm); 1073241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 1083241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 1093241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_inc_block(struct dm_space_map *sm, dm_block_t b) 1103241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 1113241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->inc_block(sm, b); 1123241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 1133241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 1143241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_dec_block(struct dm_space_map *sm, dm_block_t b) 1153241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 1163241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->dec_block(sm, b); 1173241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 1183241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 1193241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_new_block(struct dm_space_map *sm, dm_block_t *b) 1203241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 1213241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->new_block(sm, b); 1223241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 1233241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 1243241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_root_size(struct dm_space_map *sm, size_t *result) 1253241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 1263241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->root_size(sm, result); 1273241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 1283241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 1293241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornberstatic inline int dm_sm_copy_root(struct dm_space_map *sm, void *copy_to_here_le, size_t len) 1303241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber{ 1313241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber return sm->copy_root(sm, copy_to_here_le, len); 1323241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber} 1333241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber 1343241b1d3e0aaafbfcd320f4d71ade629728cc4f4Joe Thornber#endif /* _LINUX_DM_SPACE_MAP_H */ 135