Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

[safe/jmp/linux-2.6] / fs / btrfs / ref-cache.h

diff --git a/fs/btrfs/ref-cache.h b/fs/btrfs/ref-cache.h
index 79ecc47..bc283ad 100644 (file)
--- a/fs/btrfs/ref-cache.h
+++ b/fs/btrfs/ref-cache.h
@@ -15,45 +15,45 @@
  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  * Boston, MA 021110-1307, USA.
  */
+#ifndef __REFCACHE__
+#define __REFCACHE__
 
 struct btrfs_extent_info {
+       /* bytenr and num_bytes find the extent in the extent allocation tree */
        u64 bytenr;
        u64 num_bytes;
+
+       /* objectid and offset find the back reference for the file */
        u64 objectid;
        u64 offset;
 };
 
 struct btrfs_leaf_ref {
        struct rb_node rb_node;
-       struct btrfs_key key;
+       struct btrfs_leaf_ref_tree *tree;
        int in_tree;
        atomic_t usage;
 
+       u64 root_gen;
        u64 bytenr;
        u64 owner;
        u64 generation;
        int nritems;
-       struct btrfs_extent_info extents[];
-};
 
-struct btrfs_leaf_ref_tree {
-       struct rb_root root;
-       struct btrfs_leaf_ref *last;
-       u64 generation;
-       spinlock_t lock;
+       struct list_head list;
+       struct btrfs_extent_info extents[];
 };
 
 static inline size_t btrfs_leaf_ref_size(int nr_extents)
 {
-       return sizeof(struct btrfs_leaf_ref) + 
+       return sizeof(struct btrfs_leaf_ref) +
               sizeof(struct btrfs_extent_info) * nr_extents;
 }
 
 static inline void btrfs_leaf_ref_tree_init(struct btrfs_leaf_ref_tree *tree)
 {
        tree->root.rb_node = NULL;
-       tree->last = NULL;
-       tree->generation = 0;
+       INIT_LIST_HEAD(&tree->list);
        spin_lock_init(&tree->lock);
 }
 
@@ -63,10 +63,14 @@ static inline int btrfs_leaf_ref_tree_empty(struct btrfs_leaf_ref_tree *tree)
 }
 
 void btrfs_leaf_ref_tree_init(struct btrfs_leaf_ref_tree *tree);
-struct btrfs_leaf_ref *btrfs_alloc_leaf_ref(int nr_extents);
-void btrfs_free_leaf_ref(struct btrfs_leaf_ref *ref);
+struct btrfs_leaf_ref *btrfs_alloc_leaf_ref(struct btrfs_root *root,
+                                           int nr_extents);
+void btrfs_free_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref);
 struct btrfs_leaf_ref *btrfs_lookup_leaf_ref(struct btrfs_root *root,
-                                            struct btrfs_key *key);
-int btrfs_add_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref);
-int btrfs_remove_leaf_refs(struct btrfs_root *root);
+                                            u64 bytenr);
+int btrfs_add_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref,
+                      int shared);
+int btrfs_remove_leaf_refs(struct btrfs_root *root, u64 max_root_gen,
+                          int shared);
 int btrfs_remove_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref);
+#endif