freebsd-skq/sys/i4b/layer2/i4b_util.c
jlemon 954e1d2ccd Lock down the network interface queues. The queue mutex must be obtained
before adding/removing packets from the queue.  Also, the if_obytes and
if_omcasts fields should only be manipulated under protection of the mutex.

IF_ENQUEUE, IF_PREPEND, and IF_DEQUEUE perform all necessary locking on
the queue.  An IF_LOCK macro is provided, as well as the old (mutex-less)
versions of the macros in the form _IF_ENQUEUE, _IF_QFULL, for code which
needs them, but their use is discouraged.

Two new macros are introduced: IF_DRAIN() to drain a queue, and IF_HANDOFF,
which takes care of locking/enqueue, and also statistics updating/start
if necessary.
2000-11-25 07:35:38 +00:00

326 lines
8.2 KiB
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_util.c - layer 2 utility routines
* -------------------------------------
*
* $Id: i4b_util.c,v 1.26 2000/08/24 11:48:58 hm Exp $
*
* $FreeBSD$
*
* last edit-date: [Mon May 29 16:55:35 2000]
*
*---------------------------------------------------------------------------*/
#ifdef __FreeBSD__
#include "i4bq921.h"
#else
#define NI4BQ921 1
#endif
#if NI4BQ921 > 0
#include <sys/param.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>
#else
#include <i4b/i4b_debug.h>
#include <i4b/i4b_ioctl.h>
#endif
#include <i4b/include/i4b_global.h>
#include <i4b/include/i4b_l1l2.h>
#include <i4b/include/i4b_mbuf.h>
#include <i4b/layer2/i4b_l2.h>
/*---------------------------------------------------------------------------*
* routine ESTABLISH DATA LINK (Q.921 03/93 page 83)
*---------------------------------------------------------------------------*/
void
i4b_establish_data_link(l2_softc_t *l2sc)
{
i4b_l1_activate(l2sc);
i4b_clear_exception_conditions(l2sc);
l2sc->RC = 0;
i4b_tx_sabme(l2sc, P1);
i4b_T200_restart(l2sc);
i4b_T203_stop(l2sc);
}
/*---------------------------------------------------------------------------*
* routine CLEAR EXCEPTION CONDITIONS (Q.921 03/93 page 83)
*---------------------------------------------------------------------------*/
void
i4b_clear_exception_conditions(l2_softc_t *l2sc)
{
CRIT_VAR;
CRIT_BEG;
/*XXX -------------------------------------------------------------- */
/*XXX is this really appropriate here or should it moved elsewhere ? */
i4b_Dcleanifq(&l2sc->i_queue);
if(l2sc->ua_num != UA_EMPTY)
{
i4b_Dfreembuf(l2sc->ua_frame);
l2sc->ua_num = UA_EMPTY;
}
/*XXX -------------------------------------------------------------- */
l2sc->peer_busy = 0;
l2sc->rej_excpt = 0;
l2sc->own_busy = 0;
l2sc->ack_pend = 0;
CRIT_END;
}
/*---------------------------------------------------------------------------*
* routine TRANSMIT ENQUIRE (Q.921 03/93 page 83)
*---------------------------------------------------------------------------*/
void
i4b_transmit_enquire(l2_softc_t *l2sc)
{
if(l2sc->own_busy)
i4b_tx_rnr_command(l2sc, P1);
else
i4b_tx_rr_command(l2sc, P1);
l2sc->ack_pend = 0;
i4b_T200_start(l2sc);
}
/*---------------------------------------------------------------------------*
* routine NR ERROR RECOVERY (Q.921 03/93 page 83)
*---------------------------------------------------------------------------*/
void
i4b_nr_error_recovery(l2_softc_t *l2sc)
{
i4b_mdl_error_ind(l2sc, "i4b_nr_error_recovery", MDL_ERR_J);
i4b_establish_data_link(l2sc);
l2sc->l3initiated = 0;
}
/*---------------------------------------------------------------------------*
* routine ENQUIRY RESPONSE (Q.921 03/93 page 84)
*---------------------------------------------------------------------------*/
void
i4b_enquiry_response(l2_softc_t *l2sc)
{
if(l2sc->own_busy)
i4b_tx_rnr_response(l2sc, F1);
else
i4b_tx_rr_response(l2sc, F1);
l2sc->ack_pend = 0;
}
/*---------------------------------------------------------------------------*
* routine INVOKE RETRANSMISSION (Q.921 03/93 page 84)
*---------------------------------------------------------------------------*/
void
i4b_invoke_retransmission(l2_softc_t *l2sc, int nr)
{
CRIT_VAR;
CRIT_BEG;
NDBGL2(L2_ERROR, "nr = %d", nr );
while(l2sc->vs != nr)
{
NDBGL2(L2_ERROR, "nr(%d) != vs(%d)", nr, l2sc->vs);
M128DEC(l2sc->vs);
/* XXXXXXXXXXXXXXXXX */
if((l2sc->ua_num != UA_EMPTY) && (l2sc->vs == l2sc->ua_num))
{
if(_IF_QFULL(&l2sc->i_queue))
{
NDBGL2(L2_ERROR, "ERROR, I-queue full!");
}
else
{
IF_ENQUEUE(&l2sc->i_queue, l2sc->ua_frame);
l2sc->ua_num = UA_EMPTY;
}
}
else
{
NDBGL2(L2_ERROR, "ERROR, l2sc->vs = %d, l2sc->ua_num = %d ",l2sc->vs, l2sc->ua_num);
}
/* XXXXXXXXXXXXXXXXX */
i4b_i_frame_queued_up(l2sc);
}
CRIT_END;
}
/*---------------------------------------------------------------------------*
* routine ACKNOWLEDGE PENDING (Q.921 03/93 p 70)
*---------------------------------------------------------------------------*/
void
i4b_acknowledge_pending(l2_softc_t *l2sc)
{
if(l2sc->ack_pend)
{
l2sc->ack_pend = 0;
i4b_tx_rr_response(l2sc, F0);
}
}
/*---------------------------------------------------------------------------*
* i4b_print_frame - just print the hex contents of a frame
*---------------------------------------------------------------------------*/
void
i4b_print_frame(int len, u_char *buf)
{
#if DO_I4B_DEBUG
int i;
if (!(i4b_l2_debug & L2_ERROR)) /* XXXXXXXXXXXXXXXXXXXXX */
return;
for(i = 0; i < len; i++)
printf(" 0x%x", buf[i]);
printf("\n");
#endif
}
/*---------------------------------------------------------------------------*
* i4b_print_l2var - print some l2softc vars
*---------------------------------------------------------------------------*/
void
i4b_print_l2var(l2_softc_t *l2sc)
{
NDBGL2(L2_ERROR, "unit%d V(R)=%d, V(S)=%d, V(A)=%d,ACKP=%d,PBSY=%d,OBSY=%d",
l2sc->unit,
l2sc->vr,
l2sc->vs,
l2sc->va,
l2sc->ack_pend,
l2sc->peer_busy,
l2sc->own_busy);
}
/*---------------------------------------------------------------------------*
* got s or i frame, check if valid ack for last sent frame
*---------------------------------------------------------------------------*/
void
i4b_rxd_ack(l2_softc_t *l2sc, int nr)
{
#ifdef NOTDEF
NDBGL2(L2_ERROR, "N(R)=%d, UA=%d, V(R)=%d, V(S)=%d, V(A)=%d",
nr,
l2sc->ua_num,
l2sc->vr,
l2sc->vs,
l2sc->va);
#endif
if(l2sc->ua_num != UA_EMPTY)
{
CRIT_VAR;
CRIT_BEG;
M128DEC(nr);
if(l2sc->ua_num != nr)
NDBGL2(L2_ERROR, "((N(R)-1)=%d) != (UA=%d) !!!", nr, l2sc->ua_num);
i4b_Dfreembuf(l2sc->ua_frame);
l2sc->ua_num = UA_EMPTY;
CRIT_END;
}
}
/*---------------------------------------------------------------------------*
* if not already active, activate layer 1
*---------------------------------------------------------------------------*/
void
i4b_l1_activate(l2_softc_t *l2sc)
{
if(l2sc->ph_active == PH_INACTIVE)
{
l2sc->ph_active = PH_ACTIVEPEND;
PH_Act_Req(l2sc->unit);
}
};
/*---------------------------------------------------------------------------*
* check for v(a) <= n(r) <= v(s)
* nr = receive sequence frame counter, va = acknowledge sequence frame
* counter and vs = transmit sequence frame counter
*---------------------------------------------------------------------------*/
int
i4b_l2_nr_ok(int nr, int va, int vs)
{
if((va > nr) && ((nr != 0) || (va != 127)))
{
NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [1]", va, nr, vs);
return 0; /* fail */
}
if((nr > vs) && ((vs != 0) || (nr != 127)))
{
NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [2]", va, nr, vs);
return 0; /* fail */
}
return 1; /* good */
}
#endif /* NI4BQ921 > 0 */