btree_bset_first
return ((void *) btree_bset_first(b)) + b->written * block_bytes(b->c->cache);
struct bset *n1 = btree_bset_first(new_nodes[i]);
struct bset *n2 = btree_bset_first(new_nodes[i - 1]);
BUG_ON(btree_bset_first(new_nodes[0])->keys);
struct bset *i = btree_bset_first(b);
split = set_blocks(btree_bset_first(n1),
trace_bcache_btree_node_split(b, btree_bset_first(n1)->keys);
while (keys < (btree_bset_first(n1)->keys * 3) / 5)
keys += bkey_u64s(bset_bkey_idx(btree_bset_first(n1),
bset_bkey_idx(btree_bset_first(n1), keys));
keys += bkey_u64s(bset_bkey_idx(btree_bset_first(n1), keys));
btree_bset_first(n2)->keys = btree_bset_first(n1)->keys - keys;
btree_bset_first(n1)->keys = keys;
memcpy(btree_bset_first(n2)->start,
bset_bkey_last(btree_bset_first(n1)),
btree_bset_first(n2)->keys * sizeof(uint64_t));
trace_bcache_btree_node_compact(b, btree_bset_first(n1)->keys);
BUG_ON(btree_bset_first(b)->seq != i->seq);