nfsrv_adj
struct mbuf *nfsrv_adj(struct mbuf *, int, int);
m = nfsrv_adj(m3, len - tlen, tlen - cnt);
m2 = nfsrv_adj(m, alen - tlen, tlen - len);
mp = nfsrv_adj(mp3, NFS_MAXPATHLEN - tlen,