HASHKEY
int key = HASHKEY(uid);
for (curdisk = usglist[HASHKEY(uid)];
head = &mp->hqh[HASHKEY(bp->pgno)];
head = &mp->hqh[HASHKEY(bp->pgno)];
head = &mp->hqh[HASHKEY(bp->pgno)];
head = &mp->hqh[HASHKEY(bp->pgno)];
head = &mp->hqh[HASHKEY(bp->pgno)];
head = &mp->hqh[HASHKEY(pgno)];