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 1.3 2003/08/07 21:17:29 dillon Exp $
  34  *
  35  *      last edit-date: [Mon May 29 16:55:35 2000]
  36  *
  37  *---------------------------------------------------------------------------*/
  38
  39 #ifdef __FreeBSD__
  40 #include "use_i4bq921.h"
  41 #else
  42 #define NI4BQ921        1
  43 #endif
  44 #if NI4BQ921 > 0
  45
  46 #include <sys/param.h>
  47 #include <sys/systm.h>
  48 #include <sys/mbuf.h>
  49 #include <sys/socket.h>
  50 #include <net/if.h>
  51
  52 #if defined(__NetBSD__) && __NetBSD_Version__ >= 104230000
  53 #include <sys/callout.h>
  54 #endif
  55
  56 #ifdef __FreeBSD__
  57 #include <net/i4b/include/machine/i4b_debug.h>
  58 #else
  59 #include <i4b/i4b_debug.h>
  60 #include <i4b/i4b_ioctl.h>
  61 #endif
  62
  63 #include "../include/i4b_global.h"
  64 #include "../include/i4b_l1l2.h"
  65 #include "../include/i4b_mbuf.h"
  66
  67 #include "i4b_l2.h"
  68
  69 /*---------------------------------------------------------------------------*
  70  *      routine ESTABLISH DATA LINK (Q.921 03/93 page 83)
  71  *---------------------------------------------------------------------------*/
  72 void
  73 i4b_establish_data_link(l2_softc_t *l2sc)
  74 {
  75         i4b_l1_activate(l2sc);
  76
  77         i4b_clear_exception_conditions(l2sc);
  78
  79         l2sc->RC = 0;
  80
  81         i4b_tx_sabme(l2sc, P1);
  82
  83         i4b_T200_restart(l2sc);
  84
  85         i4b_T203_stop(l2sc);
  86 }
  87
  88 /*---------------------------------------------------------------------------*
  89  *      routine CLEAR EXCEPTION CONDITIONS (Q.921 03/93 page 83)
  90  *---------------------------------------------------------------------------*/
  91 void
  92 i4b_clear_exception_conditions(l2_softc_t *l2sc)
  93 {
  94         CRIT_VAR;
  95
  96         CRIT_BEG;
  97
  98 /*XXX -------------------------------------------------------------- */
  99 /*XXX is this really appropriate here or should it moved elsewhere ? */
 100
 101         i4b_Dcleanifq(&l2sc->i_queue);
 102
 103         if(l2sc->ua_num != UA_EMPTY)
 104         {
 105                 i4b_Dfreembuf(l2sc->ua_frame);
 106                 l2sc->ua_num = UA_EMPTY;
 107         }
 108 /*XXX -------------------------------------------------------------- */
 109
 110         l2sc->peer_busy = 0;
 111
 112         l2sc->rej_excpt = 0;
 113
 114         l2sc->own_busy = 0;
 115
 116         l2sc->ack_pend = 0;
 117
 118         CRIT_END;
 119 }
 120
 121 /*---------------------------------------------------------------------------*
 122  *      routine TRANSMIT ENQUIRE (Q.921 03/93 page 83)
 123  *---------------------------------------------------------------------------*/
 124 void
 125 i4b_transmit_enquire(l2_softc_t *l2sc)
 126 {
 127         if(l2sc->own_busy)
 128                 i4b_tx_rnr_command(l2sc, P1);
 129         else
 130                 i4b_tx_rr_command(l2sc, P1);
 131
 132         l2sc->ack_pend = 0;
 133
 134         i4b_T200_start(l2sc);
 135 }
 136
 137 /*---------------------------------------------------------------------------*
 138  *      routine NR ERROR RECOVERY (Q.921 03/93 page 83)
 139  *---------------------------------------------------------------------------*/
 140 void
 141 i4b_nr_error_recovery(l2_softc_t *l2sc)
 142 {
 143         i4b_mdl_error_ind(l2sc, "i4b_nr_error_recovery", MDL_ERR_J);
 144
 145         i4b_establish_data_link(l2sc);
 146
 147         l2sc->l3initiated = 0;
 148 }
 149
 150 /*---------------------------------------------------------------------------*
 151  *      routine ENQUIRY RESPONSE (Q.921 03/93 page 84)
 152  *---------------------------------------------------------------------------*/
 153 void
 154 i4b_enquiry_response(l2_softc_t *l2sc)
 155 {
 156         if(l2sc->own_busy)
 157                 i4b_tx_rnr_response(l2sc, F1);
 158         else
 159                 i4b_tx_rr_response(l2sc, F1);
 160
 161         l2sc->ack_pend = 0;
 162 }
 163
 164 /*---------------------------------------------------------------------------*
 165  *      routine INVOKE RETRANSMISSION (Q.921 03/93 page 84)
 166  *---------------------------------------------------------------------------*/
 167 void
 168 i4b_invoke_retransmission(l2_softc_t *l2sc, int nr)
 169 {
 170         CRIT_VAR;
 171
 172         CRIT_BEG;
 173
 174         NDBGL2(L2_ERROR, "nr = %d", nr );
 175
 176         while(l2sc->vs != nr)
 177         {
 178                 NDBGL2(L2_ERROR, "nr(%d) != vs(%d)", nr, l2sc->vs);
 179
 180                 M128DEC(l2sc->vs);
 181
 182 /* XXXXXXXXXXXXXXXXX */
 183
 184                 if((l2sc->ua_num != UA_EMPTY) && (l2sc->vs == l2sc->ua_num))
 185                 {
 186                         if(_IF_QFULL(&l2sc->i_queue))
 187                         {
 188                                 NDBGL2(L2_ERROR, "ERROR, I-queue full!");
 189                         }
 190                         else
 191                         {
 192                                 IF_ENQUEUE(&l2sc->i_queue, l2sc->ua_frame);
 193                                 l2sc->ua_num = UA_EMPTY;
 194                         }
 195                 }
 196                 else
 197                 {
 198                         NDBGL2(L2_ERROR, "ERROR, l2sc->vs = %d, l2sc->ua_num = %d ",l2sc->vs, l2sc->ua_num);
 199                 }
 200
 201 /* XXXXXXXXXXXXXXXXX */
 202
 203                 i4b_i_frame_queued_up(l2sc);
 204         }
 205
 206         CRIT_END;
 207 }
 208
 209 /*---------------------------------------------------------------------------*
 210  *      routine ACKNOWLEDGE PENDING (Q.921 03/93 p 70)
 211  *---------------------------------------------------------------------------*/
 212 void
 213 i4b_acknowledge_pending(l2_softc_t *l2sc)
 214 {
 215         if(l2sc->ack_pend)
 216         {
 217                 l2sc->ack_pend = 0;
 218                 i4b_tx_rr_response(l2sc, F0);
 219         }
 220 }
 221
 222 /*---------------------------------------------------------------------------*
 223  *      i4b_print_frame - just print the hex contents of a frame
 224  *---------------------------------------------------------------------------*/
 225 void
 226 i4b_print_frame(int len, u_char *buf)
 227 {
 228 #if DO_I4B_DEBUG
 229         int i;
 230
 231         if (!(i4b_l2_debug & L2_ERROR))         /* XXXXXXXXXXXXXXXXXXXXX */
 232                 return;
 233
 234         for(i = 0; i < len; i++)
 235                 printf(" 0x%x", buf[i]);
 236         printf("\n");
 237 #endif
 238 }
 239
 240 /*---------------------------------------------------------------------------*
 241  *      i4b_print_l2var - print some l2softc vars
 242  *---------------------------------------------------------------------------*/
 243 void
 244 i4b_print_l2var(l2_softc_t *l2sc)
 245 {
 246         NDBGL2(L2_ERROR, "unit%d V(R)=%d, V(S)=%d, V(A)=%d,ACKP=%d,PBSY=%d,OBSY=%d",
 247                 l2sc->unit,
 248                 l2sc->vr,
 249                 l2sc->vs,
 250                 l2sc->va,
 251                 l2sc->ack_pend,
 252                 l2sc->peer_busy,
 253                 l2sc->own_busy);
 254 }
 255
 256 /*---------------------------------------------------------------------------*
 257  *      got s or i frame, check if valid ack for last sent frame
 258  *---------------------------------------------------------------------------*/
 259 void
 260 i4b_rxd_ack(l2_softc_t *l2sc, int nr)
 261 {
 262
 263 #ifdef NOTDEF
 264         NDBGL2(L2_ERROR, "N(R)=%d, UA=%d, V(R)=%d, V(S)=%d, V(A)=%d",
 265                 nr,
 266                 l2sc->ua_num,
 267                 l2sc->vr,
 268                 l2sc->vs,
 269                 l2sc->va);
 270 #endif
 271
 272         if(l2sc->ua_num != UA_EMPTY)
 273         {
 274                 CRIT_VAR;
 275
 276                 CRIT_BEG;
 277
 278                 M128DEC(nr);
 279
 280                 if(l2sc->ua_num != nr)
 281                         NDBGL2(L2_ERROR, "((N(R)-1)=%d) != (UA=%d) !!!", nr, l2sc->ua_num);
 282
 283                 i4b_Dfreembuf(l2sc->ua_frame);
 284                 l2sc->ua_num = UA_EMPTY;
 285
 286                 CRIT_END;
 287         }
 288 }
 289
 290 /*---------------------------------------------------------------------------*
 291  *      if not already active, activate layer 1
 292  *---------------------------------------------------------------------------*/
 293 void
 294 i4b_l1_activate(l2_softc_t *l2sc)
 295 {
 296         if(l2sc->ph_active == PH_INACTIVE)
 297         {
 298                 l2sc->ph_active = PH_ACTIVEPEND;
 299                 PH_Act_Req(l2sc->unit);
 300         }
 301 };
 302
 303 /*---------------------------------------------------------------------------*
 304  *      check for v(a) <= n(r) <= v(s)
 305  *      nr = receive sequence frame counter, va = acknowledge sequence frame
 306  *      counter and vs = transmit sequence frame counter
 307  *---------------------------------------------------------------------------*/
 308 int
 309 i4b_l2_nr_ok(int nr, int va, int vs)
 310 {
 311         if((va > nr) && ((nr != 0) || (va != 127)))
 312         {
 313                 NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [1]", va, nr, vs);
 314                 return 0;       /* fail */
 315         }
 316
 317         if((nr > vs) && ((vs != 0) || (nr != 127)))
 318         {
 319                 NDBGL2(L2_ERROR, "ERROR, va = %d, nr = %d, vs = %d [2]", va, nr, vs);
 320                 return 0;       /* fail */
 321         }
 322         return 1;               /* good */
 323 }
 324
 325 #endif /* NI4BQ921 > 0 */
 326