diff options
Diffstat (limited to 'drivers/md/persistent-data/dm-btree-internal.h')
| -rw-r--r-- | drivers/md/persistent-data/dm-btree-internal.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/md/persistent-data/dm-btree-internal.h b/drivers/md/persistent-data/dm-btree-internal.h index b1788853a355..893edb426dba 100644 --- a/drivers/md/persistent-data/dm-btree-internal.h +++ b/drivers/md/persistent-data/dm-btree-internal.h @@ -144,4 +144,17 @@ extern struct dm_block_validator btree_node_validator; extern void init_le64_type(struct dm_transaction_manager *tm, struct dm_btree_value_type *vt); +/* + * This returns a shadowed btree leaf that you may modify. In practise + * this means overwrites only, since an insert could cause a node to + * be split. Useful if you need access to the old value to calculate the + * new one. + * + * This only works with single level btrees. The given key must be present in + * the tree, otherwise -EINVAL will be returned. + */ +int btree_get_overwrite_leaf(struct dm_btree_info *info, dm_block_t root, + uint64_t key, int *index, + dm_block_t *new_root, struct dm_block **leaf); + #endif /* DM_BTREE_INTERNAL_H */ |