bigblock
RB_ENTRY(bigblock) entry;
static RB_HEAD(bigblock_rb_tree, bigblock) ZoneTree =
RB_PROTOTYPE2(bigblock_rb_tree, bigblock, entry, bigblock_cmp, hammer_off_t);
RB_GENERATE2(bigblock_rb_tree, bigblock, entry, bigblock_cmp, hammer_off_t,