btrfs_merge_delalloc_extent
void btrfs_merge_delalloc_extent(struct btrfs_inode *inode, struct extent_state *new,
btrfs_merge_delalloc_extent(tree->inode, state, prev);
btrfs_merge_delalloc_extent(tree->inode, state, next);
btrfs_merge_delalloc_extent(tree->inode,
btrfs_merge_delalloc_extent(tree->inode,