txMaplock
tlck = txMaplock(tid, ip, tlckDTREE | tlckRELOCATE);
tlck = txMaplock(tid, ip, tlckDTREE | tlckFREE);
txMaplock(tid, ip,
tlck = txMaplock(tid, ip, tlckMAP);
tlck = txMaplock(tid, ip, tlckMAP);
extern struct tlock *txMaplock(tid_t, struct inode *, int);