NetBSD-5.0.2/sys/netisdn/i4b_iframe.c
/*
* Copyright (c) 1997, 2000 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 1.8 2005/12/11 12:25:06 christos Exp $
*
* $FreeBSD$
*
* last edit-date: [Fri Jan 5 11:33:47 2001]
*
*---------------------------------------------------------------------------*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: i4b_iframe.c,v 1.8 2005/12/11 12:25:06 christos Exp $");
#ifdef __FreeBSD__
#include "i4bq921.h"
#else
#define NI4BQ921 1
#endif
#if NI4BQ921 > 0
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <net/if.h>
#if defined(__NetBSD__) && __NetBSD_Version__ >= 104230000
#include <sys/callout.h>
#endif
#ifdef __FreeBSD__
#include <machine/i4b_debug.h>
#include <machine/i4b_ioctl.h>
#include <machine/i4b_trace.h>
#else
#include <netisdn/i4b_debug.h>
#include <netisdn/i4b_ioctl.h>
#include <netisdn/i4b_trace.h>
#endif
#include <netisdn/i4b_global.h>
#include <netisdn/i4b_l2.h>
#include <netisdn/i4b_l1l2.h>
#include <netisdn/i4b_isdnq931.h>
#include <netisdn/i4b_mbuf.h>
#include <netisdn/i4b_l2fsm.h>
/*---------------------------------------------------------------------------*
* process i frame
* implements the routine "I COMMAND" Q.921 03/93 pp 68 and pp 77
*---------------------------------------------------------------------------*/
void
i4b_rxd_i_frame(l2_softc_t *l2sc, struct isdn_l3_driver *drv, struct mbuf *m)
{
u_char *ptr = m->m_data;
int nr;
int ns;
int p;
int s;
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);
NDBGL2(L2_I_ERR, "ERROR, state != (MF || TR)!");
return;
}
s = splnet();
l2sc->stat.rx_i++; /* update frame count */
nr = GETINR(*(ptr + OFF_INR));
ns = GETINS(*(ptr + OFF_INS));
p = GETIP(*(ptr + OFF_INR));
i4b_rxd_ack(l2sc, drv, 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 */
i4b_dl_data_ind(drv, 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(s);
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(s);
}
/*---------------------------------------------------------------------------*
* internal I FRAME QUEUED UP routine (Q.921 03/93 p 61)
*---------------------------------------------------------------------------*/
void
i4b_i_frame_queued_up(l2_softc_t *l2sc)
{
struct mbuf *m;
u_char *ptr;
int s;
s = splnet();
if((l2sc->peer_busy) || (l2sc->vs == ((l2sc->va + MAX_K_VALUE) & 127)))
{
if(l2sc->peer_busy)
{
NDBGL2(L2_I_MSG, "regen IFQUP, cause: peer busy!");
}
if(l2sc->vs == ((l2sc->va + MAX_K_VALUE) & 127))
{
NDBGL2(L2_I_MSG, "regen IFQUP, cause: vs=va+k!");
}
/*
* XXX see: Q.921, page 36, 5.6.1 ".. may retransmit an I
* frame ...", shall we retransmit the last i frame ?
*/
if(!(IF_QEMPTY(&l2sc->i_queue)))
{
NDBGL2(L2_I_MSG, "re-scheduling IFQU call!");
START_TIMER(l2sc->IFQU_callout, i4b_i_frame_queued_up, l2sc, IFQU_DLY);
}
splx(s);
return;
}
IF_DEQUEUE(&l2sc->i_queue, m); /* fetch next frame to tx */
if(!m)
{
NDBGL2(L2_I_ERR, "ERROR, mbuf NULL after IF_DEQUEUE");
splx(s);
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 */
l2sc->stat.tx_i++; /* update frame counter */
l2sc->driver->ph_data_req(l2sc->l1_token, 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 */
{
NDBGL2(L2_I_ERR, "ERROR, l2sc->ua_num: %d != UA_EMPTY", 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(s);
if(l2sc->T200 == TIMER_IDLE)
{
i4b_T203_stop(l2sc);
i4b_T200_start(l2sc);
}
}
#endif /* NI4BQ921 > 0 */