hammer_node
struct hammer_node *node;
TAILQ_HEAD(hammer_node_list, hammer_node);
RB_HEAD(hammer_nod_rb_tree, hammer_node);
RB_PROTOTYPE2(hammer_nod_rb_tree, hammer_node, rb_node,
TAILQ_ENTRY(hammer_node) entry; /* per-buffer linkage */
RB_ENTRY(hammer_node) rb_node; /* per-mount linkage */
struct hammer_node;
RB_GENERATE2(hammer_nod_rb_tree, hammer_node, rb_node,