p->gen_no = 0;
/* fill the block group with garbage if sanity checking is on */
IF_DEBUG(sanity,memset(p->start, 0xaa, p->blocks * BLOCK_SIZE));
p->gen_no = 0;
/* fill the block group with garbage if sanity checking is on */
IF_DEBUG(sanity,memset(p->start, 0xaa, p->blocks * BLOCK_SIZE));