btrfs: add forward declarations and headers, part 3
Do a cleanup in the rest of the headers:
- add forward declarations for types referenced by pointers
- add includes when types need them
This fixes potential compilation problems if the headers are reordered
or the missing includes are not provided indirectly.
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/extent-tree.h b/fs/btrfs/extent-tree.h
index 3fbcb77..af9f880 100644
--- a/fs/btrfs/extent-tree.h
+++ b/fs/btrfs/extent-tree.h
@@ -13,6 +13,7 @@ struct btrfs_free_cluster;
struct btrfs_fs_info;
struct btrfs_root;
struct btrfs_path;
+struct btrfs_ref;
struct btrfs_disk_key;
struct btrfs_delayed_ref_head;
struct btrfs_delayed_ref_root;
