diff options
Diffstat (limited to 'drivers/md/persistent-data/dm-btree.h')
| -rw-r--r-- | drivers/md/persistent-data/dm-btree.h | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/drivers/md/persistent-data/dm-btree.h b/drivers/md/persistent-data/dm-btree.h index ae02c84410f..dacfc34180b 100644 --- a/drivers/md/persistent-data/dm-btree.h +++ b/drivers/md/persistent-data/dm-btree.h @@ -35,7 +35,7 @@ struct dm_transaction_manager; */ /* - * Infomation about the values stored within the btree. + * Information about the values stored within the btree. */ struct dm_btree_value_type { void *context; @@ -58,21 +58,21 @@ struct dm_btree_value_type { * somewhere.) This method is _not_ called for insertion of a new * value: It is assumed the ref count is already 1. */ - void (*inc)(void *context, void *value); + void (*inc)(void *context, const void *value); /* * This value is being deleted. The btree takes care of freeing * the memory pointed to by @value. Often the del function just * needs to decrement a reference count somewhere. */ - void (*dec)(void *context, void *value); + void (*dec)(void *context, const void *value); /* * A test for equality between two values. When a value is * overwritten with a new one, the old one has the dec method * called _unless_ the new and old value are deemed equal. */ - int (*equal)(void *context, void *value1, void *value2); + int (*equal)(void *context, const void *value1, const void *value2); }; /* @@ -137,9 +137,26 @@ int dm_btree_remove(struct dm_btree_info *info, dm_block_t root, /* * Returns < 0 on failure. Otherwise the number of key entries that have * been filled out. Remember trees can have zero entries, and as such have + * no lowest key. + */ +int dm_btree_find_lowest_key(struct dm_btree_info *info, dm_block_t root, + uint64_t *result_keys); + +/* + * Returns < 0 on failure. Otherwise the number of key entries that have + * been filled out. Remember trees can have zero entries, and as such have * no highest key. */ int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, uint64_t *result_keys); +/* + * Iterate through the a btree, calling fn() on each entry. + * It only works for single level trees and is internally recursive, so + * monitor stack usage carefully. + */ +int dm_btree_walk(struct dm_btree_info *info, dm_block_t root, + int (*fn)(void *context, uint64_t *keys, void *leaf), + void *context); + #endif /* _LINUX_DM_BTREE_H */ |