blob: 1c67ebccf73c740bf95d034802242096d64828d6 [file] [log] [blame]
* Copyright (C) 2015 Fujitsu. All rights reserved.
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* General Public License for more details.
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
#ifndef __BTRFS_FIND_ROOT_H__
#define __BTRFS_FIND_ROOT_H__
#include "kerncompat.h"
#include "ctree.h"
#include "list.h"
#include "extent-cache.h"
* Find-root will restore the search result in a 2-level trees.
* Search result is a cache_tree consisted of generation_cache.
* Each generation cache records the highest level of this generation
* and all the tree blocks with this generation.
* <result>
* cache_tree ----> generation_cache: gen:1 level: 2 eb_tree ----> eb1
* | |-> eb2
* | ......
* |-> generation_cache: gen:2 level: 3 eb_tree ---> eb3
* In the above example, generation 1's highest level is 2, but have multiple
* eb with same generation, so the root of generation 1 must be missing,
* possibly has already been overwritten.
* On the other hand, generation 2's highest level is 3 and we find only one
* eb for it, so it may be the root of generation 2.
struct btrfs_find_root_gen_cache {
struct cache_extent cache; /* cache->start is generation */
u64 highest_level;
struct cache_tree eb_tree;
struct btrfs_find_root_filter {
u64 objectid; /* Only search tree with this objectid */
u64 generation; /* Only record tree block with higher or
equal generation */
u8 level; /* Only record tree block with higher or
equal level */
u8 match_level;
u64 match_gen;
int search_all;
* If set search_all, even the tree block matches match_gen
* and match_level and objectid, still continue searching
* This *WILL* take *TONS* of extra time.
int btrfs_find_root_search(struct btrfs_root *chunk_root,
struct btrfs_find_root_filter *filter,
struct cache_tree *result,
struct cache_extent **match);
static inline void btrfs_find_root_free(struct cache_tree *result)
struct btrfs_find_root_gen_cache *gen_cache;
struct cache_extent *cache;
cache = first_cache_extent(result);
while (cache) {
gen_cache = container_of(cache,
struct btrfs_find_root_gen_cache, cache);
remove_cache_extent(result, cache);
cache = first_cache_extent(result);