1/* 2 * Copyright (C) 2008 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18#ifndef __REFCACHE__ 19#define __REFCACHE__ 20 21struct btrfs_extent_info { 22 /* bytenr and num_bytes find the extent in the extent allocation tree */ 23 u64 bytenr; 24 u64 num_bytes; 25 26 /* objectid and offset find the back reference for the file */ 27 u64 objectid; 28 u64 offset; 29}; 30 31struct btrfs_leaf_ref { 32 struct rb_node rb_node; 33 struct btrfs_leaf_ref_tree *tree; 34 int in_tree; 35 atomic_t usage; 36 37 u64 root_gen; 38 u64 bytenr; 39 u64 owner; 40 u64 generation; 41 int nritems; 42 43 struct list_head list; 44 struct btrfs_extent_info extents[]; 45}; 46 47static inline size_t btrfs_leaf_ref_size(int nr_extents) 48{ 49 return sizeof(struct btrfs_leaf_ref) + 50 sizeof(struct btrfs_extent_info) * nr_extents; 51} 52 53static inline void btrfs_leaf_ref_tree_init(struct btrfs_leaf_ref_tree *tree) 54{ 55 tree->root = RB_ROOT; 56 INIT_LIST_HEAD(&tree->list); 57 spin_lock_init(&tree->lock); 58} 59 60static inline int btrfs_leaf_ref_tree_empty(struct btrfs_leaf_ref_tree *tree) 61{ 62 return RB_EMPTY_ROOT(&tree->root); 63} 64 65void btrfs_leaf_ref_tree_init(struct btrfs_leaf_ref_tree *tree); 66struct btrfs_leaf_ref *btrfs_alloc_leaf_ref(struct btrfs_root *root, 67 int nr_extents); 68void btrfs_free_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref); 69struct btrfs_leaf_ref *btrfs_lookup_leaf_ref(struct btrfs_root *root, 70 u64 bytenr); 71int btrfs_add_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref, 72 int shared); 73int btrfs_remove_leaf_refs(struct btrfs_root *root, u64 max_root_gen, 74 int shared); 75int btrfs_remove_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref); 76#endif 77