db_aglevel
lblkno = BLKTOCTL(blkno, bmp->db_l2nbperpage, bmp->db_aglevel);
if (bmp->db_aglevel == 2)
else if (bmp->db_aglevel == 1)
dbFindCtl(bmp, l2nb, bmp->db_aglevel - 1,
bmp->db_aglevel = le32_to_cpu(dbmp_le->dn_aglevel);
dbmp_le->dn_aglevel = cpu_to_le32(bmp->db_aglevel);
bmp->db_aglevel = BMAPSZTOLEV(bmp->db_agsize);
bmp->db_agl2size - (L2BPERDMAP + bmp->db_aglevel * L2LPERCTL);