sys/net/i4b/layer2/i4b_util.c

   1 /*
   2  * Copyright (c) 1997, 2000 Hellmuth Michaelis. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  *
  25  *---------------------------------------------------------------------------
  26  *
  27  *      i4b_util.c - layer 2 utility routines
  28  *      -------------------------------------
  29  *
  30  *      $Id: i4b_util.c,v 1.26 2000/08/24 11:48:58 hm Exp $
  31  *
  32  * $FreeBSD: src/sys/i4b/layer2/i4b_util.c,v 1.6.2.1 2001/08/10 14:08:41 obrien Exp $
  33  * $DragonFly: src/sys/net/i4b/layer2/i4b_util.c,v 1.7 2005/06/14 21:19:19 joerg Exp $
  34  *
  35  *      last edit-date: [Mon May 29 16:55:35 2000]
  36  *
  37  *---------------------------------------------------------------------------*/
  38
  39 #include "use_i4bq921.h"
  40 #if NI4BQ921 > 0
  41
  42 #include <sys/param.h>
  43 #include <sys/systm.h>
  44 #include <sys/mbuf.h>
  45 #include <sys/socket.h>
  46 #include <sys/thread2.h>
  47 #include <net/if.h>
  48
  49 #include <net/i4b/include/machine/i4b_debug.h>
  50
  51 #include "../include/i4b_global.h"
  52 #include "../include/i4b_l1l2.h"
  53 #include "../include/i4b_mbuf.h"
  54
  55 #include "i4b_l2.h"
  56
  57 /*---------------------------------------------------------------------------*
  58  *      routine ESTABLISH DATA LINK (Q.921 03/93 page 83)
  59  *---------------------------------------------------------------------------*/
  60 void
  61 i4b_establish_data_link(l2_softc_t *l2sc)
  62 {
  63         i4b_l1_activate(l2sc);
  64
  65         i4b_clear_exception_conditions(l2sc);
  66
  67         l2sc->RC = 0;
  68
  69         i4b_tx_sabme(l2sc, P1);
  70
  71         i4b_T200_restart(l2sc);
  72
  73         i4b_T203_stop(l2sc);
  74 }
  75
  76 /*---------------------------------------------------------------------------*
  77  *      routine CLEAR EXCEPTION CONDITIONS (Q.921 03/93 page 83)
  78  *---------------------------------------------------------------------------*/
  79 void
  80 i4b_clear_exception_conditions(l2_softc_t *l2sc)
  81 {
  82         CRIT_VAR;
  83
  84         CRIT_BEG;
  85
  86 /*XXX -------------------------------------------------------------- */
  87 /*XXX is this really appropriate here or should it moved elsewhere ? */
  88
  89         i4b_Dcleanifq(&l2sc->i_queue);
  90
  91         if(l2sc->ua_num != UA_EMPTY)
  92         {
  93                 i4b_Dfreembuf(l2sc->ua_frame);
  94                 l2sc->ua_num = UA_EMPTY;
  95         }
  96 /*XXX -------------------------------------------------------------- */
  97
  98         l2sc->peer_busy = 0;
  99
 100         l2sc->rej_excpt = 0;
 101
 102         l2sc->own_busy = 0;
 103
 104         l2sc->ack_pend = 0;
 105
 106         CRIT_END;
 107 }
 108
 109 /*---------------------------------------------------------------------------*
 110  *      routine TRANSMIT ENQUIRE (Q.921 03/93 page 83)
 111  *---------------------------------------------------------------------------*/
 112 void
 113 i4b_transmit_enquire(l2_softc_t *l2sc)
 114 {
 115         if(l2sc->own_busy)
 116                 i4b_tx_rnr_command(l2sc, P1);
 117         else
 118                 i4b_tx_rr_command(l2sc, P1);
 119
 120         l2sc->ack_pend = 0;
 121
 122         i4b_T200_start(l2sc);
 123 }
 124
 125 /*---------------------------------------------------------------------------*
 126  *      routine NR ERROR RECOVERY (Q.921 03/93 page 83)
 127  *---------------------------------------------------------------------------*/
 128 void
 129 i4b_nr_error_recovery(l2_softc_t *l2sc)
 130 {
 131         i4b_mdl_error_ind(l2sc, "i4b_nr_error_recovery", MDL_ERR_J);
 132
 133         i4b_establish_data_link(l2sc);
 134
 135         l2sc->l3initiated = 0;
 136 }
 137
 138 /*---------------------------------------------------------------------------*
 139  *      routine ENQUIRY RESPONSE (Q.921 03/93 page 84)
 140  *---------------------------------------------------------------------------*/
 141 void
 142 i4b_enquiry_response(l2_softc_t *l2sc)
 143 {
 144         if(l2sc->own_busy)
 145                 i4b_tx_rnr_response(l2sc, F1);
 146         else
 147                 i4b_tx_rr_response(l2sc, F1);
 148
 149         l2sc->ack_pend = 0;
 150 }
 151
 152 /*---------------------------------------------------------------------------*
 153  *      routine INVOKE RETRANSMISSION (Q.921 03/93 page 84)
 154  *---------------------------------------------------------------------------*/
 155 void
 156 i4b_invoke_retransmission(l2_softc_t *l2sc, int nr)
 157 {
 158         CRIT_VAR;
 159
 160         CRIT_BEG;
 161
 162         NDBGL2(L2_ERROR, "nr = %d", nr );
 163
 164         while(l2sc->vs != nr)
 165         {
 166                 NDBGL2(L2_ERROR, "nr(%d) != vs(%d)", nr, l2sc->vs);
 167
 168                 M128DEC(l2sc->vs);
 169
 170 /* XXXXXXXXXXXXXXXXX */
 171
 172                 if((l2sc->ua_num != UA_EMPTY) && (l2sc->vs == l2sc->ua_num))
 173                 {
 174                         if(IF_QFULL(&l2sc->i_queue))
 175                         {
 176                                 NDBGL2(L2_ERROR, "ERROR, I-queue full!");
 177                         }
 178                         else
 179                         {
 180                                 IF_ENQUEUE(&l2sc->i_queue, l2sc->ua_frame);
 181                                 l2sc->ua_num = UA_EMPTY;
 182                         }
 183                 }
 184                 else
 185                 {
 186                         NDBGL2(L2_ERROR, "ERROR, l2sc->vs = %d, l2sc->ua_num = %d ",l2sc->vs, l2sc->ua_num);
 187                 }
 188
 189 /* XXXXXXXXXXXXXXXXX */
 190
 191                 i4b_i_frame_queued_up(l2sc);
 192         }
 193
 194         CRIT_END;
 195 }
 196
 197 /*---------------------------------------------------------------------------*
 198  *      routine ACKNOWLEDGE PENDING (Q.921 03/93 p 70)
 199  *---------------------------------------------------------------------------*/
 200 void
 201 i4b_acknowledge_pending(l2_softc_t *l2sc)
 202 {
 203         if(l2sc->ack_pend)
 204         {
 205                 l2sc->ack_pend = 0;
 206                 i4b_tx_rr_response(l2sc, F0);
 207         }
 208 }
 209
 210 /*---------------------------------------------------------------------------*
 211  *      i4b_print_frame - just print the hex contents of a frame
 212  *---------------------------------------------------------------------------*/
 213 void
 214 i4b_print_frame(int len, u_char *buf)
 215 {
 216 #if DO_I4B_DEBUG
 217         int i;
 218
 219         if (!(i4b_l2_debug & L2_ERROR))         /* XXXXXXXXXXXXXXXXXXXXX */
 220                 return;
 221
 222         for(i = 0; i < len; i++)
 223                 printf(" 0x%x", buf[i]);
 224         printf("\n");
 225 #endif
 226 }
 227
 228 /*---------------------------------------------------------------------------*
 229  *      i4b_print_l2var - print some l2softc vars
 230  *---------------------------------------------------------------------------*/
 231 void
 232 i4b_print_l2var(l2_softc_t *l2sc)
 233 {
 234         NDBGL2(L2_ERROR, "unit%d V(R)=%d, V(S)=%d, V(A)=%d,ACKP=%d,PBSY=%d,OBSY=%d",
 235                 l2sc->unit,
 236                 l2sc->vr,
 237                 l2sc->vs,
 238                 l2sc->va,
 239                 l2sc->ack_pend,
 240                 l2sc->peer_busy,
 241                 l2sc->own_busy);
 242 }
 243
 244 /*---------------------------------------------------------------------------*
 245  *      got s or i frame, check if valid ack for last sent frame
 246  *---------------------------------------------------------------------------*/
 247 void
 248 i4b_rxd_ack(l2_softc_t *l2sc, int nr)
 249 {
 250
 251 #ifdef NOTDEF
 252         NDBGL2(L2_ERROR, "N(R)=%d, UA=%d, V(R)=%d, V(S)=%d, V(A)=%d",
 253                 nr,
 254                 l2sc->ua_num,
 255                 l2sc->vr,
 256                 l2sc->vs,
 257                 l2sc->va);
 258 #endif
 259
 260         if(l2sc->ua_num != UA_EMPTY)
 261         {
 262                 CRIT_VAR;
 263
 264                 CRIT_BEG;
 265
 266                 M128DEC(nr);
 267
 268                 if(l2sc->ua_num != nr)
 269                         NDBGL2(L2_ERROR, "((N(R)-1)=%d) != (UA=%d) !!!", nr, l2sc->ua_num);
 270
 271                 i4b_Dfreembuf(l2sc->ua_frame);
 272                 l2sc->ua_num = UA_EMPTY;
 273
 274                 CRIT_END;
 275         }
 276 }
 277
 278 /*---------------------------------------------------------------------------*
 279  *      if not already active, activate layer 1
 280  *---------------------------------------------------------------------------*/
 281 void
 282 i4b_l1_activate(l2_softc_t *l2sc)
 283 {
 284         if(l2sc->ph_active == PH_INACTIVE)
 285         {
 286                 l2sc->ph_active = PH_ACTIVEPEND;
 287                 PH_Act_Req(l2sc->unit);
 288         }
 289 };
 290
 291 /*---------------------------------------------------------------------------*
 292  *      check for v(a) <= n(r) <= v(s)
 293  *      nr = receive sequence frame counter, va = acknowledge sequence frame
 294  *      counter and vs = transmit sequence frame counter
 295  *---------------------------------------------------------------------------*/
 296 int
 297 i4b_l2_nr_ok(int nr, int va, int vs)
 298 {
 299         if((va > nr) && ((nr != 0) || (va != 127)))
 300         {
 301                 NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [1]", va, nr, vs);
 302                 return 0;       /* fail */
 303         }
 304
 305         if((nr > vs) && ((vs != 0) || (nr != 127)))
 306         {
 307                 NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [2]", va, nr, vs);
 308                 return 0;       /* fail */
 309         }
 310         return 1;               /* good */
 311 }
 312
 313 #endif /* NI4BQ921 > 0 */
 314