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  *
  34  *      last edit-date: [Mon May 29 16:55:35 2000]
  35  *
  36  *---------------------------------------------------------------------------*/
  37
  38 #ifdef __FreeBSD__
  39 #include "i4bq921.h"
  40 #else
  41 #define NI4BQ921        1
  42 #endif
  43 #if NI4BQ921 > 0
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #include <sys/mbuf.h>
  48 #include <sys/socket.h>
  49 #include <net/if.h>
  50
  51 #if defined(__NetBSD__) && __NetBSD_Version__ >= 104230000
  52 #include <sys/callout.h>
  53 #endif
  54
  55 #ifdef __FreeBSD__
  56 #include <machine/i4b_debug.h>
  57 #else
  58 #include <i4b/i4b_debug.h>
  59 #include <i4b/i4b_ioctl.h>
  60 #endif
  61
  62 #include <i4b/include/i4b_global.h>
  63 #include <i4b/include/i4b_l1l2.h>
  64 #include <i4b/include/i4b_mbuf.h>
  65
  66 #include <i4b/layer2/i4b_l2.h>
  67
  68 /*---------------------------------------------------------------------------*
  69  *      routine ESTABLISH DATA LINK (Q.921 03/93 page 83)
  70  *---------------------------------------------------------------------------*/
  71 void
  72 i4b_establish_data_link(l2_softc_t *l2sc)
  73 {
  74         i4b_l1_activate(l2sc);
  75
  76         i4b_clear_exception_conditions(l2sc);
  77
  78         l2sc->RC = 0;
  79
  80         i4b_tx_sabme(l2sc, P1);
  81
  82         i4b_T200_restart(l2sc);
  83
  84         i4b_T203_stop(l2sc);
  85 }
  86
  87 /*---------------------------------------------------------------------------*
  88  *      routine CLEAR EXCEPTION CONDITIONS (Q.921 03/93 page 83)
  89  *---------------------------------------------------------------------------*/
  90 void
  91 i4b_clear_exception_conditions(l2_softc_t *l2sc)
  92 {
  93         CRIT_VAR;
  94
  95         CRIT_BEG;
  96
  97 /*XXX -------------------------------------------------------------- */
  98 /*XXX is this really appropriate here or should it moved elsewhere ? */
  99
 100         i4b_Dcleanifq(&l2sc->i_queue);
 101
 102         if(l2sc->ua_num != UA_EMPTY)
 103         {
 104                 i4b_Dfreembuf(l2sc->ua_frame);
 105                 l2sc->ua_num = UA_EMPTY;
 106         }
 107 /*XXX -------------------------------------------------------------- */
 108
 109         l2sc->peer_busy = 0;
 110
 111         l2sc->rej_excpt = 0;
 112
 113         l2sc->own_busy = 0;
 114
 115         l2sc->ack_pend = 0;
 116
 117         CRIT_END;
 118 }
 119
 120 /*---------------------------------------------------------------------------*
 121  *      routine TRANSMIT ENQUIRE (Q.921 03/93 page 83)
 122  *---------------------------------------------------------------------------*/
 123 void
 124 i4b_transmit_enquire(l2_softc_t *l2sc)
 125 {
 126         if(l2sc->own_busy)
 127                 i4b_tx_rnr_command(l2sc, P1);
 128         else
 129                 i4b_tx_rr_command(l2sc, P1);
 130
 131         l2sc->ack_pend = 0;
 132
 133         i4b_T200_start(l2sc);
 134 }
 135
 136 /*---------------------------------------------------------------------------*
 137  *      routine NR ERROR RECOVERY (Q.921 03/93 page 83)
 138  *---------------------------------------------------------------------------*/
 139 void
 140 i4b_nr_error_recovery(l2_softc_t *l2sc)
 141 {
 142         i4b_mdl_error_ind(l2sc, "i4b_nr_error_recovery", MDL_ERR_J);
 143
 144         i4b_establish_data_link(l2sc);
 145
 146         l2sc->l3initiated = 0;
 147 }
 148
 149 /*---------------------------------------------------------------------------*
 150  *      routine ENQUIRY RESPONSE (Q.921 03/93 page 84)
 151  *---------------------------------------------------------------------------*/
 152 void
 153 i4b_enquiry_response(l2_softc_t *l2sc)
 154 {
 155         if(l2sc->own_busy)
 156                 i4b_tx_rnr_response(l2sc, F1);
 157         else
 158                 i4b_tx_rr_response(l2sc, F1);
 159
 160         l2sc->ack_pend = 0;
 161 }
 162
 163 /*---------------------------------------------------------------------------*
 164  *      routine INVOKE RETRANSMISSION (Q.921 03/93 page 84)
 165  *---------------------------------------------------------------------------*/
 166 void
 167 i4b_invoke_retransmission(l2_softc_t *l2sc, int nr)
 168 {
 169         CRIT_VAR;
 170
 171         CRIT_BEG;
 172
 173         NDBGL2(L2_ERROR, "nr = %d", nr );
 174
 175         while(l2sc->vs != nr)
 176         {
 177                 NDBGL2(L2_ERROR, "nr(%d) != vs(%d)", nr, l2sc->vs);
 178
 179                 M128DEC(l2sc->vs);
 180
 181 /* XXXXXXXXXXXXXXXXX */
 182
 183                 if((l2sc->ua_num != UA_EMPTY) && (l2sc->vs == l2sc->ua_num))
 184                 {
 185                         if(_IF_QFULL(&l2sc->i_queue))
 186                         {
 187                                 NDBGL2(L2_ERROR, "ERROR, I-queue full!");
 188                         }
 189                         else
 190                         {
 191                                 IF_ENQUEUE(&l2sc->i_queue, l2sc->ua_frame);
 192                                 l2sc->ua_num = UA_EMPTY;
 193                         }
 194                 }
 195                 else
 196                 {
 197                         NDBGL2(L2_ERROR, "ERROR, l2sc->vs = %d, l2sc->ua_num = %d ",l2sc->vs, l2sc->ua_num);
 198                 }
 199
 200 /* XXXXXXXXXXXXXXXXX */
 201
 202                 i4b_i_frame_queued_up(l2sc);
 203         }
 204
 205         CRIT_END;
 206 }
 207
 208 /*---------------------------------------------------------------------------*
 209  *      routine ACKNOWLEDGE PENDING (Q.921 03/93 p 70)
 210  *---------------------------------------------------------------------------*/
 211 void
 212 i4b_acknowledge_pending(l2_softc_t *l2sc)
 213 {
 214         if(l2sc->ack_pend)
 215         {
 216                 l2sc->ack_pend = 0;
 217                 i4b_tx_rr_response(l2sc, F0);
 218         }
 219 }
 220
 221 /*---------------------------------------------------------------------------*
 222  *      i4b_print_frame - just print the hex contents of a frame
 223  *---------------------------------------------------------------------------*/
 224 void
 225 i4b_print_frame(int len, u_char *buf)
 226 {
 227 #if DO_I4B_DEBUG
 228         int i;
 229
 230         if (!(i4b_l2_debug & L2_ERROR))         /* XXXXXXXXXXXXXXXXXXXXX */
 231                 return;
 232
 233         for(i = 0; i < len; i++)
 234                 printf(" 0x%x", buf[i]);
 235         printf("\n");
 236 #endif
 237 }
 238
 239 /*---------------------------------------------------------------------------*
 240  *      i4b_print_l2var - print some l2softc vars
 241  *---------------------------------------------------------------------------*/
 242 void
 243 i4b_print_l2var(l2_softc_t *l2sc)
 244 {
 245         NDBGL2(L2_ERROR, "unit%d V(R)=%d, V(S)=%d, V(A)=%d,ACKP=%d,PBSY=%d,OBSY=%d",
 246                 l2sc->unit,
 247                 l2sc->vr,
 248                 l2sc->vs,
 249                 l2sc->va,
 250                 l2sc->ack_pend,
 251                 l2sc->peer_busy,
 252                 l2sc->own_busy);
 253 }
 254
 255 /*---------------------------------------------------------------------------*
 256  *      got s or i frame, check if valid ack for last sent frame
 257  *---------------------------------------------------------------------------*/
 258 void
 259 i4b_rxd_ack(l2_softc_t *l2sc, int nr)
 260 {
 261
 262 #ifdef NOTDEF
 263         NDBGL2(L2_ERROR, "N(R)=%d, UA=%d, V(R)=%d, V(S)=%d, V(A)=%d",
 264                 nr,
 265                 l2sc->ua_num,
 266                 l2sc->vr,
 267                 l2sc->vs,
 268                 l2sc->va);
 269 #endif
 270
 271         if(l2sc->ua_num != UA_EMPTY)
 272         {
 273                 CRIT_VAR;
 274
 275                 CRIT_BEG;
 276
 277                 M128DEC(nr);
 278
 279                 if(l2sc->ua_num != nr)
 280                         NDBGL2(L2_ERROR, "((N(R)-1)=%d) != (UA=%d) !!!", nr, l2sc->ua_num);
 281
 282                 i4b_Dfreembuf(l2sc->ua_frame);
 283                 l2sc->ua_num = UA_EMPTY;
 284
 285                 CRIT_END;
 286         }
 287 }
 288
 289 /*---------------------------------------------------------------------------*
 290  *      if not already active, activate layer 1
 291  *---------------------------------------------------------------------------*/
 292 void
 293 i4b_l1_activate(l2_softc_t *l2sc)
 294 {
 295         if(l2sc->ph_active == PH_INACTIVE)
 296         {
 297                 l2sc->ph_active = PH_ACTIVEPEND;
 298                 PH_Act_Req(l2sc->unit);
 299         }
 300 };
 301
 302 /*---------------------------------------------------------------------------*
 303  *      check for v(a) <= n(r) <= v(s)
 304  *      nr = receive sequence frame counter, va = acknowledge sequence frame
 305  *      counter and vs = transmit sequence frame counter
 306  *---------------------------------------------------------------------------*/
 307 int
 308 i4b_l2_nr_ok(int nr, int va, int vs)
 309 {
 310         if((va > nr) && ((nr != 0) || (va != 127)))
 311         {
 312                 NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [1]", va, nr, vs);
 313                 return 0;       /* fail */
 314         }
 315
 316         if((nr > vs) && ((vs != 0) || (nr != 127)))
 317         {
 318                 NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [2]", va, nr, vs);
 319                 return 0;       /* fail */
 320         }
 321         return 1;               /* good */
 322 }
 323
 324 #endif /* NI4BQ921 > 0 */
 325