RESERVE_BTREE
if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, wait))
if (fifo_used(&ca->free[RESERVE_BTREE]) < reserve) {
fifo_full(&ca->free[RESERVE_BTREE]))
fifo_push(&ca->free[RESERVE_BTREE],
if (!init_fifo(&ca->free[RESERVE_BTREE], btree_buckets,
free_fifo(&ca->free[RESERVE_BTREE]);
if (bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, true))