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_iframe.c - i frame handling routines
28 * ------------------------------------------
29 *
30 * $Id: i4b_iframe.c,v 1.1 2003/04/06 04:37:48 tg Exp $
31 *
32 * $FreeBSD$
33 *
34 * last edit-date: [Fri Jan 5 11:33:47 2001]
35 *
36 *---------------------------------------------------------------------------*/
37
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: i4b_iframe.c,v 1.6 2002/05/21 10:31:10 martin Exp $");
40
41 #ifdef __FreeBSD__
42 #include "i4bq921.h"
43 #else
44 #define NI4BQ921 1
45 #endif
46 #if NI4BQ921 > 0
47
48 #include <sys/param.h>
49 #include <sys/kernel.h>
50 #include <sys/systm.h>
51 #include <sys/mbuf.h>
52 #include <sys/socket.h>
53 #include <net/if.h>
54
55 #include <sys/timeout.h>
56
57 #ifdef __FreeBSD__
58 #include <machine/i4b_debug.h>
59 #include <machine/i4b_ioctl.h>
60 #include <machine/i4b_trace.h>
61 #else
62 #include <netisdn/i4b_debug.h>
63 #include <netisdn/i4b_ioctl.h>
64 #include <netisdn/i4b_trace.h>
65 #endif
66
67 #include <netisdn/i4b_global.h>
68 #include <netisdn/i4b_l2.h>
69 #include <netisdn/i4b_l1l2.h>
70 #include <netisdn/i4b_isdnq931.h>
71 #include <netisdn/i4b_mbuf.h>
72 #include <netisdn/i4b_l2fsm.h>
73
74 /*---------------------------------------------------------------------------*
75 * process i frame
76 * implements the routine "I COMMAND" Q.921 03/93 pp 68 and pp 77
77 *---------------------------------------------------------------------------*/
78 void
i4b_rxd_i_frame(l2_softc_t * l2sc,struct isdn_l3_driver * drv,struct mbuf * m)79 i4b_rxd_i_frame(l2_softc_t *l2sc, struct isdn_l3_driver *drv, struct mbuf *m)
80 {
81 u_char *ptr = m->m_data;
82 int nr;
83 int ns;
84 int p;
85 int s;
86
87 if(!((l2sc->tei_valid == TEI_VALID) &&
88 (l2sc->tei == GETTEI(*(ptr+OFF_TEI)))))
89 {
90 i4b_Dfreembuf(m);
91 return;
92 }
93
94 if((l2sc->Q921_state != ST_MULTIFR) && (l2sc->Q921_state != ST_TIMREC))
95 {
96 i4b_Dfreembuf(m);
97 NDBGL2(L2_I_ERR, "ERROR, state != (MF || TR)!");
98 return;
99 }
100
101 s = splnet();
102
103 l2sc->stat.rx_i++; /* update frame count */
104
105 nr = GETINR(*(ptr + OFF_INR));
106 ns = GETINS(*(ptr + OFF_INS));
107 p = GETIP(*(ptr + OFF_INR));
108
109 i4b_rxd_ack(l2sc, drv, nr); /* last packet ack */
110
111 if(l2sc->own_busy) /* own receiver busy ? */
112 {
113 i4b_Dfreembuf(m); /* yes, discard information */
114
115 if(p == 1) /* P bit == 1 ? */
116 {
117 i4b_tx_rnr_response(l2sc, p); /* yes, tx RNR */
118 l2sc->ack_pend = 0; /* clear ACK pending */
119 }
120 }
121 else /* own receiver ready */
122 {
123 if(ns == l2sc->vr) /* expected sequence number ? */
124 {
125 M128INC(l2sc->vr); /* yes, update */
126
127 l2sc->rej_excpt = 0; /* clr reject exception */
128
129 m_adj(m, I_HDR_LEN); /* strip i frame header */
130
131 l2sc->iframe_sent = 0; /* reset i acked already */
132
133 i4b_dl_data_ind(drv, m); /* pass data up */
134
135 if(!l2sc->iframe_sent)
136 {
137 i4b_tx_rr_response(l2sc, p); /* yes, tx RR */
138 l2sc->ack_pend = 0; /* clr ACK pending */
139 }
140 }
141 else /* ERROR, sequence number NOT expected */
142 {
143 i4b_Dfreembuf(m); /* discard information */
144
145 if(l2sc->rej_excpt == 1) /* already exception ? */
146 {
147 if(p == 1) /* immediate response ? */
148 {
149 i4b_tx_rr_response(l2sc, p); /* yes, tx RR */
150 l2sc->ack_pend = 0; /* clr ack pend */
151 }
152 }
153 else /* not in exception cond */
154 {
155 l2sc->rej_excpt = 1; /* set exception */
156 i4b_tx_rej_response(l2sc, p); /* tx REJ */
157 l2sc->ack_pend = 0; /* clr ack pending */
158 }
159 }
160 }
161
162 /* sequence number ranges as expected ? */
163
164 if(i4b_l2_nr_ok(nr, l2sc->va, l2sc->vs))
165 {
166 if(l2sc->Q921_state == ST_TIMREC)
167 {
168 l2sc->va = nr;
169
170 splx(s);
171
172 return;
173 }
174
175 if(l2sc->peer_busy) /* yes, other side busy ? */
176 {
177 l2sc->va = nr; /* yes, update ack count */
178 }
179 else /* other side ready */
180 {
181 if(nr == l2sc->vs) /* count expected ? */
182 {
183 l2sc->va = nr; /* update ack */
184 i4b_T200_stop(l2sc);
185 i4b_T203_restart(l2sc);
186 }
187 else
188 {
189 if(nr != l2sc->va)
190 {
191 l2sc->va = nr;
192 i4b_T200_restart(l2sc);
193 }
194 }
195 }
196 }
197 else
198 {
199 i4b_nr_error_recovery(l2sc); /* sequence error */
200 l2sc->Q921_state = ST_AW_EST;
201 }
202
203 splx(s);
204 }
205
206 /*---------------------------------------------------------------------------*
207 * internal I FRAME QUEUED UP routine (Q.921 03/93 p 61)
208 *---------------------------------------------------------------------------*/
209 void
i4b_i_frame_queued_up(l2_softc_t * l2sc)210 i4b_i_frame_queued_up(l2_softc_t *l2sc)
211 {
212 struct mbuf *m;
213 u_char *ptr;
214 int s;
215
216 s = splnet();
217
218 if((l2sc->peer_busy) || (l2sc->vs == ((l2sc->va + MAX_K_VALUE) & 127)))
219 {
220 if(l2sc->peer_busy)
221 {
222 NDBGL2(L2_I_MSG, "regen IFQUP, cause: peer busy!");
223 }
224
225 if(l2sc->vs == ((l2sc->va + MAX_K_VALUE) & 127))
226 {
227 NDBGL2(L2_I_MSG, "regen IFQUP, cause: vs=va+k!");
228 }
229
230 /*
231 * XXX see: Q.921, page 36, 5.6.1 ".. may retransmit an I
232 * frame ...", shall we retransmit the last i frame ?
233 */
234
235 if(!(IF_QEMPTY(&l2sc->i_queue)))
236 {
237 NDBGL2(L2_I_MSG, "re-scheduling IFQU call!");
238 START_TIMER(l2sc->IFQU_callout, i4b_i_frame_queued_up, l2sc, IFQU_DLY);
239 }
240 splx(s);
241 return;
242 }
243
244 IF_DEQUEUE(&l2sc->i_queue, m); /* fetch next frame to tx */
245
246 if(!m)
247 {
248 NDBGL2(L2_I_ERR, "ERROR, mbuf NULL after IF_DEQUEUE");
249 splx(s);
250 return;
251 }
252
253 ptr = m->m_data;
254
255 PUTSAPI(SAPI_CCP, CR_CMD_TO_NT, *(ptr + OFF_SAPI));
256 PUTTEI(l2sc->tei, *(ptr + OFF_TEI));
257
258 *(ptr + OFF_INS) = (l2sc->vs << 1) & 0xfe; /* bit 0 = 0 */
259 *(ptr + OFF_INR) = (l2sc->vr << 1) & 0xfe; /* P bit = 0 */
260
261 l2sc->stat.tx_i++; /* update frame counter */
262
263 l2sc->driver->ph_data_req(l2sc->l1_token, m, MBUF_DONTFREE); /* free'd when ack'd ! */
264
265 l2sc->iframe_sent = 1; /* in case we ack an I frame with another I frame */
266
267 if(l2sc->ua_num != UA_EMPTY) /* failsafe */
268 {
269 NDBGL2(L2_I_ERR, "ERROR, l2sc->ua_num: %d != UA_EMPTY", l2sc->ua_num);
270 i4b_print_l2var(l2sc);
271 i4b_Dfreembuf(l2sc->ua_frame);
272 }
273
274 l2sc->ua_frame = m; /* save unacked frame */
275 l2sc->ua_num = l2sc->vs; /* save frame number */
276
277 M128INC(l2sc->vs);
278
279 l2sc->ack_pend = 0;
280
281 splx(s);
282
283 if(l2sc->T200 == TIMER_IDLE)
284 {
285 i4b_T203_stop(l2sc);
286 i4b_T200_start(l2sc);
287 }
288 }
289
290 #endif /* NI4BQ921 > 0 */
291