seq_before
if (seq_before(seq, ppp->nextseq)) {
if (seq_before(ch->lastseq, seq))
if (seq_before(ppp->minseq, seq))
if (seq_before(ppp->minseq, PPP_MP_CB(mskb)->sequence))
if (seq_before(seq, PPP_MP_CB(p)->sequence))
if (seq_before(PPP_MP_CB(p)->sequence, seq)) {
seq = seq_before(minseq, PPP_MP_CB(p)->sequence)?