freebsd-dev/sys/i4b/layer2/i4b_iframe.c

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/*
* Copyright (c) 1997, 1998 Hellmuth Michaelis. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*---------------------------------------------------------------------------
*
* i4b_iframe.c - i frame handling routines
* ------------------------------------------
*
* $Id: i4b_iframe.c,v 1.15 1998/12/05 18:05:06 hm Exp $
*
* last edit-date: [Sat Dec 5 18:26:16 1998]
*
*---------------------------------------------------------------------------*/
#ifdef __FreeBSD__
#include "i4bq921.h"
#else
#define NI4BQ921 1
#endif
#if NI4BQ921 > 0
#include <sys/param.h>
#if defined(__FreeBSD__) && __FreeBSD__ >= 3
#include <sys/ioccom.h>
#else
#include <sys/ioctl.h>
#endif
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <net/if.h>
#ifdef __FreeBSD__
#include <machine/i4b_debug.h>
#include <machine/i4b_ioctl.h>
#include <machine/i4b_trace.h>
#else
#include <i4b/i4b_debug.h>
#include <i4b/i4b_ioctl.h>
#include <i4b/i4b_trace.h>
#endif
#include <i4b/include/i4b_global.h>
#include <i4b/include/i4b_l1l2.h>
#include <i4b/include/i4b_l2l3.h>
#include <i4b/include/i4b_isdnq931.h>
#include <i4b/include/i4b_mbuf.h>
#include <i4b/layer2/i4b_l2.h>
#include <i4b/layer2/i4b_l2fsm.h>
/*---------------------------------------------------------------------------*
* process i frame
* implements the routine "I COMMAND" Q.921 03/93 pp 77
*---------------------------------------------------------------------------*/
void
i4b_rxd_i_frame(int unit, struct mbuf *m)
{
l2_softc_t *l2sc = &l2_softc[unit];
u_char *ptr = m->m_data;
int nr;
int ns;
int p;
int x;
if(!((l2sc->tei_valid == TEI_VALID) &&
(l2sc->tei == GETTEI(*(ptr+OFF_TEI)))))
{
i4b_Dfreembuf(m);
return;
}
if((l2sc->Q921_state != ST_MULTIFR) && (l2sc->Q921_state != ST_TIMREC))
{
i4b_Dfreembuf(m);
DBGL2(L2_I_ERR, "i4b_rxd_i_frame", ("ERROR, state != (MF || TR)!\n"));
return;
}
x = SPLI4B();
nr = GETINR(*(ptr + OFF_INR));
ns = GETINS(*(ptr + OFF_INS));
p = GETIP(*(ptr + OFF_INR));
i4b_rxd_ack(l2sc, nr); /* last packet ack */
if(l2sc->own_busy) /* own receiver busy ? */
{
i4b_Dfreembuf(m); /* yes, discard information */
if(p == 1) /* P bit == 1 ? */
{
i4b_tx_rnr_response(l2sc, p); /* yes, tx RNR */
l2sc->ack_pend = 0; /* clear ACK pending */
}
}
else /* own receiver ready */
{
if(ns == l2sc->vr) /* expected sequence number ? */
{
M128INC(l2sc->vr); /* yes, update */
l2sc->rej_excpt = 0; /* clr reject exception */
m_adj(m, I_HDR_LEN); /* strip i frame header */
l2sc->iframe_sent = 0; /* reset i acked already */
DL_Data_Ind(l2sc->unit, m); /* pass data up */
if(!l2sc->iframe_sent)
{
i4b_tx_rr_response(l2sc, p); /* yes, tx RR */
l2sc->ack_pend = 0; /* clr ACK pending */
}
}
else /* ERROR, sequence number NOT expected */
{
i4b_Dfreembuf(m); /* discard information */
if(l2sc->rej_excpt == 1) /* already exception ? */
{
if(p == 1) /* immediate response ? */
{
i4b_tx_rr_response(l2sc, p); /* yes, tx RR */
l2sc->ack_pend = 0; /* clr ack pend */
}
}
else /* not in exception cond */
{
l2sc->rej_excpt = 1; /* set exception */
i4b_tx_rej_response(l2sc, p); /* tx REJ */
l2sc->ack_pend = 0; /* clr ack pending */
}
}
}
/* sequence number ranges as expected ? */
if(i4b_l2_nr_ok(nr, l2sc->va, l2sc->vs))
{
if(l2sc->Q921_state == ST_TIMREC)
{
l2sc->va = nr;
splx(x);
return;
}
if(l2sc->peer_busy) /* yes, other side busy ? */
{
l2sc->va = nr; /* yes, update ack count */
}
else /* other side ready */
{
if(nr == l2sc->vs) /* count expected ? */
{
l2sc->va = nr; /* update ack */
i4b_T200_stop(l2sc);
i4b_T203_restart(l2sc);
}
else
{
if(nr != l2sc->va)
{
l2sc->va = nr;
i4b_T200_restart(l2sc);
}
}
}
}
else
{
i4b_nr_error_recovery(l2sc); /* sequence error */
l2sc->Q921_state = ST_AW_EST;
}
splx(x);
}
/*---------------------------------------------------------------------------*
* internal I FRAME QUEUED UP routine (Q.921 03/93 p 61)
*---------------------------------------------------------------------------*/
void
i4b_i_frame_queued_up(l2_softc_t *l2sc)
{
int x;
struct mbuf *m;
u_char *ptr;
x = SPLI4B();
if(l2sc->peer_busy)
{
DBGL2(L2_I_MSG, "i4b_i_frame_queued_up", ("peer busy!\n"));
i4b_print_l2var(l2sc);
splx(x);
return;
}
if(l2sc->vs == ((l2sc->va + MAX_K_VALUE) & 127))
{
DBGL2(L2_I_ERR, "i4b_i_frame_queued_up", ("V(S) == ((V(A) + k) & 127)!\n"));
DBGL2(L2_I_ERR, "i4b_i_frame_queued_up", ("state = %s\n", i4b_print_l2state(l2sc)));
i4b_print_l2var(l2sc);
splx(x);
return;
}
IF_DEQUEUE(&l2sc->i_queue, m); /* fetch next frame to tx */
if(!m)
{
DBGL2(L2_I_ERR, "i4b_i_frame_queued_up", ("ERROR, mbuf NULL after IF_DEQUEUE\n"));
splx(x);
return;
}
ptr = m->m_data;
PUTSAPI(SAPI_CCP, CR_CMD_TO_NT, *(ptr + OFF_SAPI));
PUTTEI(l2sc->tei, *(ptr + OFF_TEI));
*(ptr + OFF_INS) = (l2sc->vs << 1) & 0xfe; /* bit 0 = 0 */
*(ptr + OFF_INR) = (l2sc->vr << 1) & 0xfe; /* P bit = 0 */
PH_Data_Req(l2sc->unit, m, MBUF_DONTFREE); /* free'd when ack'd ! */
l2sc->iframe_sent = 1; /* in case we ack an I frame with another I frame */
if(l2sc->ua_num != UA_EMPTY) /* failsafe */
{
DBGL2(L2_I_ERR, "i4b_i_frame_queued_up", ("ERROR, l2sc->ua_num: %d != UA_EMPTY\n", l2sc->ua_num));
i4b_print_l2var(l2sc);
i4b_Dfreembuf(l2sc->ua_frame);
}
l2sc->ua_frame = m; /* save unacked frame */
l2sc->ua_num = l2sc->vs; /* save frame number */
M128INC(l2sc->vs);
l2sc->ack_pend = 0;
splx(x);
if(l2sc->T200 == TIMER_IDLE)
{
i4b_T203_stop(l2sc);
i4b_T200_start(l2sc);
}
}
#endif /* NI4BQ921 > 0 */