ES_MASK
return es->es_pblk & ~ES_MASK;
return pblock == ~ES_MASK ? 0 : pblock;
block = (pb & ~ES_MASK) | (es->es_pblk & ES_MASK);
es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
(pb & ~ES_MASK);