BHASH
bcopy(bc->bcache_data + (bcache_blksize * BHASH(bc, blk)),
p_buf = bc->bcache_data + (bcache_blksize * BHASH(bc, p_blk));
r_size = bc->bcache_nblks - BHASH(bc, p_blk); /* remaining blocks */
ra = bc->bcache_nblks - BHASH(bc, p_blk + p_size);
bcopy(bc->bcache_data + (bcache_blksize * BHASH(bc, blk)),
cblk = bcache_nblks - BHASH(bc, blk);
cand = BHASH(bc, blkno);
i = BHASH(bc, blkno);
((bc)->bcache_ctl[BHASH((bc), (blkno))].bc_blkno != (blkno))