fs/btrfs/ref-cache.h

   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
  21 struct btrfs_extent_info {
  22         u64 bytenr;
  23         u64 num_bytes;
  24         u64 objectid;
  25         u64 offset;
  26 };
  27
  28 struct btrfs_leaf_ref {
  29         struct rb_node rb_node;
  30         int in_tree;
  31         atomic_t usage;
  32
  33         u64 bytenr;
  34         u64 owner;
  35         u64 generation;
  36         int nritems;
  37
  38         struct list_head list;
  39         struct btrfs_extent_info extents[];
  40 };
  41
  42 static inline size_t btrfs_leaf_ref_size(int nr_extents)
  43 {
  44         return sizeof(struct btrfs_leaf_ref) +
  45                sizeof(struct btrfs_extent_info) * nr_extents;
  46 }
  47
  48 static inline void btrfs_leaf_ref_tree_init(struct btrfs_leaf_ref_tree *tree)
  49 {
  50         tree->root.rb_node = NULL;
  51         tree->last = NULL;
  52         INIT_LIST_HEAD(&tree->list);
  53         spin_lock_init(&tree->lock);
  54 }
  55
  56 static inline int btrfs_leaf_ref_tree_empty(struct btrfs_leaf_ref_tree *tree)
  57 {
  58         return RB_EMPTY_ROOT(&tree->root);
  59 }
  60
  61 void btrfs_leaf_ref_tree_init(struct btrfs_leaf_ref_tree *tree);
  62 struct btrfs_leaf_ref *btrfs_alloc_leaf_ref(int nr_extents);
  63 void btrfs_free_leaf_ref(struct btrfs_leaf_ref *ref);
  64 struct btrfs_leaf_ref *btrfs_lookup_leaf_ref(struct btrfs_root *root,
  65                                              u64 bytenr);
  66 int btrfs_add_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref);
  67 int btrfs_remove_leaf_refs(struct btrfs_root *root);
  68 int btrfs_remove_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref);
  69
  70 #endif