1 /* $Id: isdnl2.c,v 2.30.2.4 2004/02/11 13:21:34 keil Exp $
2  *
3  * Author       Karsten Keil
4  *              based on the teles driver from Jan den Ouden
5  * Copyright    by Karsten Keil      <keil@isdn4linux.de>
6  *
7  * This software may be used and distributed according to the terms
8  * of the GNU General Public License, incorporated herein by reference.
9  *
10  * For changes and modifications please read
11  * Documentation/isdn/HiSax.cert
12  *
13  * Thanks to    Jan den Ouden
14  *              Fritz Elfert
15  *
16  */
17 
18 #include <linux/init.h>
19 #include <linux/gfp.h>
20 #include "hisax.h"
21 #include "isdnl2.h"
22 
23 const char *l2_revision = "$Revision: 2.30.2.4 $";
24 
25 static void l2m_debug(struct FsmInst *fi, char *fmt, ...);
26 
27 static struct Fsm l2fsm;
28 
29 enum {
30 	ST_L2_1,
31 	ST_L2_2,
32 	ST_L2_3,
33 	ST_L2_4,
34 	ST_L2_5,
35 	ST_L2_6,
36 	ST_L2_7,
37 	ST_L2_8,
38 };
39 
40 #define L2_STATE_COUNT (ST_L2_8 + 1)
41 
42 static char *strL2State[] =
43 {
44 	"ST_L2_1",
45 	"ST_L2_2",
46 	"ST_L2_3",
47 	"ST_L2_4",
48 	"ST_L2_5",
49 	"ST_L2_6",
50 	"ST_L2_7",
51 	"ST_L2_8",
52 };
53 
54 enum {
55 	EV_L2_UI,
56 	EV_L2_SABME,
57 	EV_L2_DISC,
58 	EV_L2_DM,
59 	EV_L2_UA,
60 	EV_L2_FRMR,
61 	EV_L2_SUPER,
62 	EV_L2_I,
63 	EV_L2_DL_DATA,
64 	EV_L2_ACK_PULL,
65 	EV_L2_DL_UNIT_DATA,
66 	EV_L2_DL_ESTABLISH_REQ,
67 	EV_L2_DL_RELEASE_REQ,
68 	EV_L2_MDL_ASSIGN,
69 	EV_L2_MDL_REMOVE,
70 	EV_L2_MDL_ERROR,
71 	EV_L1_DEACTIVATE,
72 	EV_L2_T200,
73 	EV_L2_T203,
74 	EV_L2_SET_OWN_BUSY,
75 	EV_L2_CLEAR_OWN_BUSY,
76 	EV_L2_FRAME_ERROR,
77 };
78 
79 #define L2_EVENT_COUNT (EV_L2_FRAME_ERROR + 1)
80 
81 static char *strL2Event[] =
82 {
83 	"EV_L2_UI",
84 	"EV_L2_SABME",
85 	"EV_L2_DISC",
86 	"EV_L2_DM",
87 	"EV_L2_UA",
88 	"EV_L2_FRMR",
89 	"EV_L2_SUPER",
90 	"EV_L2_I",
91 	"EV_L2_DL_DATA",
92 	"EV_L2_ACK_PULL",
93 	"EV_L2_DL_UNIT_DATA",
94 	"EV_L2_DL_ESTABLISH_REQ",
95 	"EV_L2_DL_RELEASE_REQ",
96 	"EV_L2_MDL_ASSIGN",
97 	"EV_L2_MDL_REMOVE",
98 	"EV_L2_MDL_ERROR",
99 	"EV_L1_DEACTIVATE",
100 	"EV_L2_T200",
101 	"EV_L2_T203",
102 	"EV_L2_SET_OWN_BUSY",
103 	"EV_L2_CLEAR_OWN_BUSY",
104 	"EV_L2_FRAME_ERROR",
105 };
106 
107 static int l2addrsize(struct Layer2 *l2);
108 
109 static void
set_peer_busy(struct Layer2 * l2)110 set_peer_busy(struct Layer2 *l2) {
111 	test_and_set_bit(FLG_PEER_BUSY, &l2->flag);
112 	if (!skb_queue_empty(&l2->i_queue) ||
113 	    !skb_queue_empty(&l2->ui_queue))
114 		test_and_set_bit(FLG_L2BLOCK, &l2->flag);
115 }
116 
117 static void
clear_peer_busy(struct Layer2 * l2)118 clear_peer_busy(struct Layer2 *l2) {
119 	if (test_and_clear_bit(FLG_PEER_BUSY, &l2->flag))
120 		test_and_clear_bit(FLG_L2BLOCK, &l2->flag);
121 }
122 
123 static void
InitWin(struct Layer2 * l2)124 InitWin(struct Layer2 *l2)
125 {
126 	int i;
127 
128 	for (i = 0; i < MAX_WINDOW; i++)
129 		l2->windowar[i] = NULL;
130 }
131 
132 static int
freewin1(struct Layer2 * l2)133 freewin1(struct Layer2 *l2)
134 {
135 	int i, cnt = 0;
136 
137 	for (i = 0; i < MAX_WINDOW; i++) {
138 		if (l2->windowar[i]) {
139 			cnt++;
140 			dev_kfree_skb(l2->windowar[i]);
141 			l2->windowar[i] = NULL;
142 		}
143 	}
144 	return cnt;
145 }
146 
147 static inline void
freewin(struct PStack * st)148 freewin(struct PStack *st)
149 {
150 	freewin1(&st->l2);
151 }
152 
153 static void
ReleaseWin(struct Layer2 * l2)154 ReleaseWin(struct Layer2 *l2)
155 {
156 	int cnt;
157 
158 	if ((cnt = freewin1(l2)))
159 		printk(KERN_WARNING "isdl2 freed %d skbuffs in release\n", cnt);
160 }
161 
162 static inline unsigned int
cansend(struct PStack * st)163 cansend(struct PStack *st)
164 {
165 	unsigned int p1;
166 
167 	if (test_bit(FLG_MOD128, &st->l2.flag))
168 		p1 = (st->l2.vs - st->l2.va) % 128;
169 	else
170 		p1 = (st->l2.vs - st->l2.va) % 8;
171 	return ((p1 < st->l2.window) && !test_bit(FLG_PEER_BUSY, &st->l2.flag));
172 }
173 
174 static inline void
clear_exception(struct Layer2 * l2)175 clear_exception(struct Layer2 *l2)
176 {
177 	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
178 	test_and_clear_bit(FLG_REJEXC, &l2->flag);
179 	test_and_clear_bit(FLG_OWN_BUSY, &l2->flag);
180 	clear_peer_busy(l2);
181 }
182 
183 static inline int
l2headersize(struct Layer2 * l2,int ui)184 l2headersize(struct Layer2 *l2, int ui)
185 {
186 	return (((test_bit(FLG_MOD128, &l2->flag) && (!ui)) ? 2 : 1) +
187 		(test_bit(FLG_LAPD, &l2->flag) ? 2 : 1));
188 }
189 
190 inline int
l2addrsize(struct Layer2 * l2)191 l2addrsize(struct Layer2 *l2)
192 {
193 	return (test_bit(FLG_LAPD, &l2->flag) ? 2 : 1);
194 }
195 
196 static int
sethdraddr(struct Layer2 * l2,u_char * header,int rsp)197 sethdraddr(struct Layer2 *l2, u_char *header, int rsp)
198 {
199 	u_char *ptr = header;
200 	int crbit = rsp;
201 
202 	if (test_bit(FLG_LAPD, &l2->flag)) {
203 		*ptr++ = (l2->sap << 2) | (rsp ? 2 : 0);
204 		*ptr++ = (l2->tei << 1) | 1;
205 		return (2);
206 	} else {
207 		if (test_bit(FLG_ORIG, &l2->flag))
208 			crbit = !crbit;
209 		if (crbit)
210 			*ptr++ = 1;
211 		else
212 			*ptr++ = 3;
213 		return (1);
214 	}
215 }
216 
217 static inline void
enqueue_super(struct PStack * st,struct sk_buff * skb)218 enqueue_super(struct PStack *st,
219 	      struct sk_buff *skb)
220 {
221 	if (test_bit(FLG_LAPB, &st->l2.flag))
222 		st->l1.bcs->tx_cnt += skb->len;
223 	st->l2.l2l1(st, PH_DATA | REQUEST, skb);
224 }
225 
226 #define enqueue_ui(a, b) enqueue_super(a, b)
227 
228 static inline int
IsUI(u_char * data)229 IsUI(u_char *data)
230 {
231 	return ((data[0] & 0xef) == UI);
232 }
233 
234 static inline int
IsUA(u_char * data)235 IsUA(u_char *data)
236 {
237 	return ((data[0] & 0xef) == UA);
238 }
239 
240 static inline int
IsDM(u_char * data)241 IsDM(u_char *data)
242 {
243 	return ((data[0] & 0xef) == DM);
244 }
245 
246 static inline int
IsDISC(u_char * data)247 IsDISC(u_char *data)
248 {
249 	return ((data[0] & 0xef) == DISC);
250 }
251 
252 static inline int
IsSFrame(u_char * data,struct PStack * st)253 IsSFrame(u_char *data, struct PStack *st)
254 {
255 	register u_char d = *data;
256 
257 	if (!test_bit(FLG_MOD128, &st->l2.flag))
258 		d &= 0xf;
259 	return (((d & 0xf3) == 1) && ((d & 0x0c) != 0x0c));
260 }
261 
262 static inline int
IsSABME(u_char * data,struct PStack * st)263 IsSABME(u_char *data, struct PStack *st)
264 {
265 	u_char d = data[0] & ~0x10;
266 
267 	return (test_bit(FLG_MOD128, &st->l2.flag) ? d == SABME : d == SABM);
268 }
269 
270 static inline int
IsREJ(u_char * data,struct PStack * st)271 IsREJ(u_char *data, struct PStack *st)
272 {
273 	return (test_bit(FLG_MOD128, &st->l2.flag) ? data[0] == REJ : (data[0] & 0xf) == REJ);
274 }
275 
276 static inline int
IsFRMR(u_char * data)277 IsFRMR(u_char *data)
278 {
279 	return ((data[0] & 0xef) == FRMR);
280 }
281 
282 static inline int
IsRNR(u_char * data,struct PStack * st)283 IsRNR(u_char *data, struct PStack *st)
284 {
285 	return (test_bit(FLG_MOD128, &st->l2.flag) ? data[0] == RNR : (data[0] & 0xf) == RNR);
286 }
287 
288 static int
iframe_error(struct PStack * st,struct sk_buff * skb)289 iframe_error(struct PStack *st, struct sk_buff *skb)
290 {
291 	int i = l2addrsize(&st->l2) + (test_bit(FLG_MOD128, &st->l2.flag) ? 2 : 1);
292 	int rsp = *skb->data & 0x2;
293 
294 	if (test_bit(FLG_ORIG, &st->l2.flag))
295 		rsp = !rsp;
296 
297 	if (rsp)
298 		return 'L';
299 
300 
301 	if (skb->len < i)
302 		return 'N';
303 
304 	if ((skb->len - i) > st->l2.maxlen)
305 		return 'O';
306 
307 
308 	return 0;
309 }
310 
311 static int
super_error(struct PStack * st,struct sk_buff * skb)312 super_error(struct PStack *st, struct sk_buff *skb)
313 {
314 	if (skb->len != l2addrsize(&st->l2) +
315 	    (test_bit(FLG_MOD128, &st->l2.flag) ? 2 : 1))
316 		return 'N';
317 
318 	return 0;
319 }
320 
321 static int
unnum_error(struct PStack * st,struct sk_buff * skb,int wantrsp)322 unnum_error(struct PStack *st, struct sk_buff *skb, int wantrsp)
323 {
324 	int rsp = (*skb->data & 0x2) >> 1;
325 	if (test_bit(FLG_ORIG, &st->l2.flag))
326 		rsp = !rsp;
327 
328 	if (rsp != wantrsp)
329 		return 'L';
330 
331 	if (skb->len != l2addrsize(&st->l2) + 1)
332 		return 'N';
333 
334 	return 0;
335 }
336 
337 static int
UI_error(struct PStack * st,struct sk_buff * skb)338 UI_error(struct PStack *st, struct sk_buff *skb)
339 {
340 	int rsp = *skb->data & 0x2;
341 	if (test_bit(FLG_ORIG, &st->l2.flag))
342 		rsp = !rsp;
343 
344 	if (rsp)
345 		return 'L';
346 
347 	if (skb->len > st->l2.maxlen + l2addrsize(&st->l2) + 1)
348 		return 'O';
349 
350 	return 0;
351 }
352 
353 static int
FRMR_error(struct PStack * st,struct sk_buff * skb)354 FRMR_error(struct PStack *st, struct sk_buff *skb)
355 {
356 	int headers = l2addrsize(&st->l2) + 1;
357 	u_char *datap = skb->data + headers;
358 	int rsp = *skb->data & 0x2;
359 
360 	if (test_bit(FLG_ORIG, &st->l2.flag))
361 		rsp = !rsp;
362 
363 	if (!rsp)
364 		return 'L';
365 
366 	if (test_bit(FLG_MOD128, &st->l2.flag)) {
367 		if (skb->len < headers + 5)
368 			return 'N';
369 		else
370 			l2m_debug(&st->l2.l2m, "FRMR information %2x %2x %2x %2x %2x",
371 				  datap[0], datap[1], datap[2],
372 				  datap[3], datap[4]);
373 	} else {
374 		if (skb->len < headers + 3)
375 			return 'N';
376 		else
377 			l2m_debug(&st->l2.l2m, "FRMR information %2x %2x %2x",
378 				  datap[0], datap[1], datap[2]);
379 	}
380 
381 	return 0;
382 }
383 
384 static unsigned int
legalnr(struct PStack * st,unsigned int nr)385 legalnr(struct PStack *st, unsigned int nr)
386 {
387 	struct Layer2 *l2 = &st->l2;
388 
389 	if (test_bit(FLG_MOD128, &l2->flag))
390 		return ((nr - l2->va) % 128) <= ((l2->vs - l2->va) % 128);
391 	else
392 		return ((nr - l2->va) % 8) <= ((l2->vs - l2->va) % 8);
393 }
394 
395 static void
setva(struct PStack * st,unsigned int nr)396 setva(struct PStack *st, unsigned int nr)
397 {
398 	struct Layer2 *l2 = &st->l2;
399 	int len;
400 	u_long flags;
401 
402 	spin_lock_irqsave(&l2->lock, flags);
403 	while (l2->va != nr) {
404 		(l2->va)++;
405 		if (test_bit(FLG_MOD128, &l2->flag))
406 			l2->va %= 128;
407 		else
408 			l2->va %= 8;
409 		len = l2->windowar[l2->sow]->len;
410 		if (PACKET_NOACK == l2->windowar[l2->sow]->pkt_type)
411 			len = -1;
412 		dev_kfree_skb(l2->windowar[l2->sow]);
413 		l2->windowar[l2->sow] = NULL;
414 		l2->sow = (l2->sow + 1) % l2->window;
415 		spin_unlock_irqrestore(&l2->lock, flags);
416 		if (test_bit(FLG_LLI_L2WAKEUP, &st->lli.flag) && (len >= 0))
417 			lli_writewakeup(st, len);
418 		spin_lock_irqsave(&l2->lock, flags);
419 	}
420 	spin_unlock_irqrestore(&l2->lock, flags);
421 }
422 
423 static void
send_uframe(struct PStack * st,u_char cmd,u_char cr)424 send_uframe(struct PStack *st, u_char cmd, u_char cr)
425 {
426 	struct sk_buff *skb;
427 	u_char tmp[MAX_HEADER_LEN];
428 	int i;
429 
430 	i = sethdraddr(&st->l2, tmp, cr);
431 	tmp[i++] = cmd;
432 	if (!(skb = alloc_skb(i, GFP_ATOMIC))) {
433 		printk(KERN_WARNING "isdl2 can't alloc sbbuff for send_uframe\n");
434 		return;
435 	}
436 	skb_put_data(skb, tmp, i);
437 	enqueue_super(st, skb);
438 }
439 
440 static inline u_char
get_PollFlag(struct PStack * st,struct sk_buff * skb)441 get_PollFlag(struct PStack *st, struct sk_buff *skb)
442 {
443 	return (skb->data[l2addrsize(&(st->l2))] & 0x10);
444 }
445 
446 static inline u_char
get_PollFlagFree(struct PStack * st,struct sk_buff * skb)447 get_PollFlagFree(struct PStack *st, struct sk_buff *skb)
448 {
449 	u_char PF;
450 
451 	PF = get_PollFlag(st, skb);
452 	dev_kfree_skb(skb);
453 	return (PF);
454 }
455 
456 static inline void
start_t200(struct PStack * st,int i)457 start_t200(struct PStack *st, int i)
458 {
459 	FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, i);
460 	test_and_set_bit(FLG_T200_RUN, &st->l2.flag);
461 }
462 
463 static inline void
restart_t200(struct PStack * st,int i)464 restart_t200(struct PStack *st, int i)
465 {
466 	FsmRestartTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, i);
467 	test_and_set_bit(FLG_T200_RUN, &st->l2.flag);
468 }
469 
470 static inline void
stop_t200(struct PStack * st,int i)471 stop_t200(struct PStack *st, int i)
472 {
473 	if (test_and_clear_bit(FLG_T200_RUN, &st->l2.flag))
474 		FsmDelTimer(&st->l2.t200, i);
475 }
476 
477 static inline void
st5_dl_release_l2l3(struct PStack * st)478 st5_dl_release_l2l3(struct PStack *st)
479 {
480 	int pr;
481 
482 	if (test_and_clear_bit(FLG_PEND_REL, &st->l2.flag))
483 		pr = DL_RELEASE | CONFIRM;
484 	else
485 		pr = DL_RELEASE | INDICATION;
486 
487 	st->l2.l2l3(st, pr, NULL);
488 }
489 
490 static inline void
lapb_dl_release_l2l3(struct PStack * st,int f)491 lapb_dl_release_l2l3(struct PStack *st, int f)
492 {
493 	if (test_bit(FLG_LAPB, &st->l2.flag))
494 		st->l2.l2l1(st, PH_DEACTIVATE | REQUEST, NULL);
495 	st->l2.l2l3(st, DL_RELEASE | f, NULL);
496 }
497 
498 static void
establishlink(struct FsmInst * fi)499 establishlink(struct FsmInst *fi)
500 {
501 	struct PStack *st = fi->userdata;
502 	u_char cmd;
503 
504 	clear_exception(&st->l2);
505 	st->l2.rc = 0;
506 	cmd = (test_bit(FLG_MOD128, &st->l2.flag) ? SABME : SABM) | 0x10;
507 	send_uframe(st, cmd, CMD);
508 	FsmDelTimer(&st->l2.t203, 1);
509 	restart_t200(st, 1);
510 	test_and_clear_bit(FLG_PEND_REL, &st->l2.flag);
511 	freewin(st);
512 	FsmChangeState(fi, ST_L2_5);
513 }
514 
515 static void
l2_mdl_error_ua(struct FsmInst * fi,int event,void * arg)516 l2_mdl_error_ua(struct FsmInst *fi, int event, void *arg)
517 {
518 	struct sk_buff *skb = arg;
519 	struct PStack *st = fi->userdata;
520 
521 	if (get_PollFlagFree(st, skb))
522 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'C');
523 	else
524 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'D');
525 }
526 
527 static void
l2_mdl_error_dm(struct FsmInst * fi,int event,void * arg)528 l2_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
529 {
530 	struct sk_buff *skb = arg;
531 	struct PStack *st = fi->userdata;
532 
533 	if (get_PollFlagFree(st, skb))
534 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'B');
535 	else {
536 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'E');
537 		establishlink(fi);
538 		test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
539 	}
540 }
541 
542 static void
l2_st8_mdl_error_dm(struct FsmInst * fi,int event,void * arg)543 l2_st8_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
544 {
545 	struct sk_buff *skb = arg;
546 	struct PStack *st = fi->userdata;
547 
548 	if (get_PollFlagFree(st, skb))
549 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'B');
550 	else {
551 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'E');
552 	}
553 	establishlink(fi);
554 	test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
555 }
556 
557 static void
l2_go_st3(struct FsmInst * fi,int event,void * arg)558 l2_go_st3(struct FsmInst *fi, int event, void *arg)
559 {
560 	FsmChangeState(fi, ST_L2_3);
561 }
562 
563 static void
l2_mdl_assign(struct FsmInst * fi,int event,void * arg)564 l2_mdl_assign(struct FsmInst *fi, int event, void *arg)
565 {
566 	struct PStack *st = fi->userdata;
567 
568 	FsmChangeState(fi, ST_L2_3);
569 	st->l2.l2tei(st, MDL_ASSIGN | INDICATION, NULL);
570 }
571 
572 static void
l2_queue_ui_assign(struct FsmInst * fi,int event,void * arg)573 l2_queue_ui_assign(struct FsmInst *fi, int event, void *arg)
574 {
575 	struct PStack *st = fi->userdata;
576 	struct sk_buff *skb = arg;
577 
578 	skb_queue_tail(&st->l2.ui_queue, skb);
579 	FsmChangeState(fi, ST_L2_2);
580 	st->l2.l2tei(st, MDL_ASSIGN | INDICATION, NULL);
581 }
582 
583 static void
l2_queue_ui(struct FsmInst * fi,int event,void * arg)584 l2_queue_ui(struct FsmInst *fi, int event, void *arg)
585 {
586 	struct PStack *st = fi->userdata;
587 	struct sk_buff *skb = arg;
588 
589 	skb_queue_tail(&st->l2.ui_queue, skb);
590 }
591 
592 static void
tx_ui(struct PStack * st)593 tx_ui(struct PStack *st)
594 {
595 	struct sk_buff *skb;
596 	u_char header[MAX_HEADER_LEN];
597 	int i;
598 
599 	i = sethdraddr(&(st->l2), header, CMD);
600 	header[i++] = UI;
601 	while ((skb = skb_dequeue(&st->l2.ui_queue))) {
602 		memcpy(skb_push(skb, i), header, i);
603 		enqueue_ui(st, skb);
604 	}
605 }
606 
607 static void
l2_send_ui(struct FsmInst * fi,int event,void * arg)608 l2_send_ui(struct FsmInst *fi, int event, void *arg)
609 {
610 	struct PStack *st = fi->userdata;
611 	struct sk_buff *skb = arg;
612 
613 	skb_queue_tail(&st->l2.ui_queue, skb);
614 	tx_ui(st);
615 }
616 
617 static void
l2_got_ui(struct FsmInst * fi,int event,void * arg)618 l2_got_ui(struct FsmInst *fi, int event, void *arg)
619 {
620 	struct PStack *st = fi->userdata;
621 	struct sk_buff *skb = arg;
622 
623 	skb_pull(skb, l2headersize(&st->l2, 1));
624 	st->l2.l2l3(st, DL_UNIT_DATA | INDICATION, skb);
625 /*	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
626  *		in states 1-3 for broadcast
627  */
628 
629 
630 }
631 
632 static void
l2_establish(struct FsmInst * fi,int event,void * arg)633 l2_establish(struct FsmInst *fi, int event, void *arg)
634 {
635 	struct PStack *st = fi->userdata;
636 
637 	establishlink(fi);
638 	test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
639 }
640 
641 static void
l2_discard_i_setl3(struct FsmInst * fi,int event,void * arg)642 l2_discard_i_setl3(struct FsmInst *fi, int event, void *arg)
643 {
644 	struct PStack *st = fi->userdata;
645 
646 	skb_queue_purge(&st->l2.i_queue);
647 	test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
648 	test_and_clear_bit(FLG_PEND_REL, &st->l2.flag);
649 }
650 
651 static void
l2_l3_reestablish(struct FsmInst * fi,int event,void * arg)652 l2_l3_reestablish(struct FsmInst *fi, int event, void *arg)
653 {
654 	struct PStack *st = fi->userdata;
655 
656 	skb_queue_purge(&st->l2.i_queue);
657 	establishlink(fi);
658 	test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
659 }
660 
661 static void
l2_release(struct FsmInst * fi,int event,void * arg)662 l2_release(struct FsmInst *fi, int event, void *arg)
663 {
664 	struct PStack *st = fi->userdata;
665 
666 	st->l2.l2l3(st, DL_RELEASE | CONFIRM, NULL);
667 }
668 
669 static void
l2_pend_rel(struct FsmInst * fi,int event,void * arg)670 l2_pend_rel(struct FsmInst *fi, int event, void *arg)
671 {
672 	struct PStack *st = fi->userdata;
673 
674 	test_and_set_bit(FLG_PEND_REL, &st->l2.flag);
675 }
676 
677 static void
l2_disconnect(struct FsmInst * fi,int event,void * arg)678 l2_disconnect(struct FsmInst *fi, int event, void *arg)
679 {
680 	struct PStack *st = fi->userdata;
681 
682 	skb_queue_purge(&st->l2.i_queue);
683 	freewin(st);
684 	FsmChangeState(fi, ST_L2_6);
685 	st->l2.rc = 0;
686 	send_uframe(st, DISC | 0x10, CMD);
687 	FsmDelTimer(&st->l2.t203, 1);
688 	restart_t200(st, 2);
689 }
690 
691 static void
l2_start_multi(struct FsmInst * fi,int event,void * arg)692 l2_start_multi(struct FsmInst *fi, int event, void *arg)
693 {
694 	struct PStack *st = fi->userdata;
695 	struct sk_buff *skb = arg;
696 
697 	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);
698 
699 	clear_exception(&st->l2);
700 	st->l2.vs = 0;
701 	st->l2.va = 0;
702 	st->l2.vr = 0;
703 	st->l2.sow = 0;
704 	FsmChangeState(fi, ST_L2_7);
705 	FsmAddTimer(&st->l2.t203, st->l2.T203, EV_L2_T203, NULL, 3);
706 
707 	st->l2.l2l3(st, DL_ESTABLISH | INDICATION, NULL);
708 }
709 
710 static void
l2_send_UA(struct FsmInst * fi,int event,void * arg)711 l2_send_UA(struct FsmInst *fi, int event, void *arg)
712 {
713 	struct PStack *st = fi->userdata;
714 	struct sk_buff *skb = arg;
715 
716 	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);
717 }
718 
719 static void
l2_send_DM(struct FsmInst * fi,int event,void * arg)720 l2_send_DM(struct FsmInst *fi, int event, void *arg)
721 {
722 	struct PStack *st = fi->userdata;
723 	struct sk_buff *skb = arg;
724 
725 	send_uframe(st, DM | get_PollFlagFree(st, skb), RSP);
726 }
727 
728 static void
l2_restart_multi(struct FsmInst * fi,int event,void * arg)729 l2_restart_multi(struct FsmInst *fi, int event, void *arg)
730 {
731 	struct PStack *st = fi->userdata;
732 	struct sk_buff *skb = arg;
733 	int est = 0, state;
734 
735 	state = fi->state;
736 
737 	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);
738 
739 	st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'F');
740 
741 	if (st->l2.vs != st->l2.va) {
742 		skb_queue_purge(&st->l2.i_queue);
743 		est = 1;
744 	}
745 
746 	clear_exception(&st->l2);
747 	st->l2.vs = 0;
748 	st->l2.va = 0;
749 	st->l2.vr = 0;
750 	st->l2.sow = 0;
751 	FsmChangeState(fi, ST_L2_7);
752 	stop_t200(st, 3);
753 	FsmRestartTimer(&st->l2.t203, st->l2.T203, EV_L2_T203, NULL, 3);
754 
755 	if (est)
756 		st->l2.l2l3(st, DL_ESTABLISH | INDICATION, NULL);
757 
758 	if ((ST_L2_7 == state) || (ST_L2_8 == state))
759 		if (!skb_queue_empty(&st->l2.i_queue) && cansend(st))
760 			st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
761 }
762 
763 static void
l2_stop_multi(struct FsmInst * fi,int event,void * arg)764 l2_stop_multi(struct FsmInst *fi, int event, void *arg)
765 {
766 	struct PStack *st = fi->userdata;
767 	struct sk_buff *skb = arg;
768 
769 	FsmChangeState(fi, ST_L2_4);
770 	FsmDelTimer(&st->l2.t203, 3);
771 	stop_t200(st, 4);
772 
773 	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);
774 
775 	skb_queue_purge(&st->l2.i_queue);
776 	freewin(st);
777 	lapb_dl_release_l2l3(st, INDICATION);
778 }
779 
780 static void
l2_connected(struct FsmInst * fi,int event,void * arg)781 l2_connected(struct FsmInst *fi, int event, void *arg)
782 {
783 	struct PStack *st = fi->userdata;
784 	struct sk_buff *skb = arg;
785 	int pr = -1;
786 
787 	if (!get_PollFlag(st, skb)) {
788 		l2_mdl_error_ua(fi, event, arg);
789 		return;
790 	}
791 	dev_kfree_skb(skb);
792 
793 	if (test_and_clear_bit(FLG_PEND_REL, &st->l2.flag))
794 		l2_disconnect(fi, event, arg);
795 
796 	if (test_and_clear_bit(FLG_L3_INIT, &st->l2.flag)) {
797 		pr = DL_ESTABLISH | CONFIRM;
798 	} else if (st->l2.vs != st->l2.va) {
799 		skb_queue_purge(&st->l2.i_queue);
800 		pr = DL_ESTABLISH | INDICATION;
801 	}
802 
803 	stop_t200(st, 5);
804 
805 	st->l2.vr = 0;
806 	st->l2.vs = 0;
807 	st->l2.va = 0;
808 	st->l2.sow = 0;
809 	FsmChangeState(fi, ST_L2_7);
810 	FsmAddTimer(&st->l2.t203, st->l2.T203, EV_L2_T203, NULL, 4);
811 
812 	if (pr != -1)
813 		st->l2.l2l3(st, pr, NULL);
814 
815 	if (!skb_queue_empty(&st->l2.i_queue) && cansend(st))
816 		st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
817 }
818 
819 static void
l2_released(struct FsmInst * fi,int event,void * arg)820 l2_released(struct FsmInst *fi, int event, void *arg)
821 {
822 	struct PStack *st = fi->userdata;
823 	struct sk_buff *skb = arg;
824 
825 	if (!get_PollFlag(st, skb)) {
826 		l2_mdl_error_ua(fi, event, arg);
827 		return;
828 	}
829 	dev_kfree_skb(skb);
830 
831 	stop_t200(st, 6);
832 	lapb_dl_release_l2l3(st, CONFIRM);
833 	FsmChangeState(fi, ST_L2_4);
834 }
835 
836 static void
l2_reestablish(struct FsmInst * fi,int event,void * arg)837 l2_reestablish(struct FsmInst *fi, int event, void *arg)
838 {
839 	struct PStack *st = fi->userdata;
840 	struct sk_buff *skb = arg;
841 
842 	if (!get_PollFlagFree(st, skb)) {
843 		establishlink(fi);
844 		test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
845 	}
846 }
847 
848 static void
l2_st5_dm_release(struct FsmInst * fi,int event,void * arg)849 l2_st5_dm_release(struct FsmInst *fi, int event, void *arg)
850 {
851 	struct PStack *st = fi->userdata;
852 	struct sk_buff *skb = arg;
853 
854 	if (get_PollFlagFree(st, skb)) {
855 		stop_t200(st, 7);
856 		if (!test_bit(FLG_L3_INIT, &st->l2.flag))
857 			skb_queue_purge(&st->l2.i_queue);
858 		if (test_bit(FLG_LAPB, &st->l2.flag))
859 			st->l2.l2l1(st, PH_DEACTIVATE | REQUEST, NULL);
860 		st5_dl_release_l2l3(st);
861 		FsmChangeState(fi, ST_L2_4);
862 	}
863 }
864 
865 static void
l2_st6_dm_release(struct FsmInst * fi,int event,void * arg)866 l2_st6_dm_release(struct FsmInst *fi, int event, void *arg)
867 {
868 	struct PStack *st = fi->userdata;
869 	struct sk_buff *skb = arg;
870 
871 	if (get_PollFlagFree(st, skb)) {
872 		stop_t200(st, 8);
873 		lapb_dl_release_l2l3(st, CONFIRM);
874 		FsmChangeState(fi, ST_L2_4);
875 	}
876 }
877 
878 static inline void
enquiry_cr(struct PStack * st,u_char typ,u_char cr,u_char pf)879 enquiry_cr(struct PStack *st, u_char typ, u_char cr, u_char pf)
880 {
881 	struct sk_buff *skb;
882 	struct Layer2 *l2;
883 	u_char tmp[MAX_HEADER_LEN];
884 	int i;
885 
886 	l2 = &st->l2;
887 	i = sethdraddr(l2, tmp, cr);
888 	if (test_bit(FLG_MOD128, &l2->flag)) {
889 		tmp[i++] = typ;
890 		tmp[i++] = (l2->vr << 1) | (pf ? 1 : 0);
891 	} else
892 		tmp[i++] = (l2->vr << 5) | typ | (pf ? 0x10 : 0);
893 	if (!(skb = alloc_skb(i, GFP_ATOMIC))) {
894 		printk(KERN_WARNING "isdl2 can't alloc sbbuff for enquiry_cr\n");
895 		return;
896 	}
897 	skb_put_data(skb, tmp, i);
898 	enqueue_super(st, skb);
899 }
900 
901 static inline void
enquiry_response(struct PStack * st)902 enquiry_response(struct PStack *st)
903 {
904 	if (test_bit(FLG_OWN_BUSY, &st->l2.flag))
905 		enquiry_cr(st, RNR, RSP, 1);
906 	else
907 		enquiry_cr(st, RR, RSP, 1);
908 	test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag);
909 }
910 
911 static inline void
transmit_enquiry(struct PStack * st)912 transmit_enquiry(struct PStack *st)
913 {
914 	if (test_bit(FLG_OWN_BUSY, &st->l2.flag))
915 		enquiry_cr(st, RNR, CMD, 1);
916 	else
917 		enquiry_cr(st, RR, CMD, 1);
918 	test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag);
919 	start_t200(st, 9);
920 }
921 
922 
923 static void
nrerrorrecovery(struct FsmInst * fi)924 nrerrorrecovery(struct FsmInst *fi)
925 {
926 	struct PStack *st = fi->userdata;
927 
928 	st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'J');
929 	establishlink(fi);
930 	test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
931 }
932 
933 static void
invoke_retransmission(struct PStack * st,unsigned int nr)934 invoke_retransmission(struct PStack *st, unsigned int nr)
935 {
936 	struct Layer2 *l2 = &st->l2;
937 	u_int p1;
938 	u_long flags;
939 
940 	spin_lock_irqsave(&l2->lock, flags);
941 	if (l2->vs != nr) {
942 		while (l2->vs != nr) {
943 			(l2->vs)--;
944 			if (test_bit(FLG_MOD128, &l2->flag)) {
945 				l2->vs %= 128;
946 				p1 = (l2->vs - l2->va) % 128;
947 			} else {
948 				l2->vs %= 8;
949 				p1 = (l2->vs - l2->va) % 8;
950 			}
951 			p1 = (p1 + l2->sow) % l2->window;
952 			if (test_bit(FLG_LAPB, &l2->flag))
953 				st->l1.bcs->tx_cnt += l2->windowar[p1]->len + l2headersize(l2, 0);
954 			skb_queue_head(&l2->i_queue, l2->windowar[p1]);
955 			l2->windowar[p1] = NULL;
956 		}
957 		spin_unlock_irqrestore(&l2->lock, flags);
958 		st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
959 		return;
960 	}
961 	spin_unlock_irqrestore(&l2->lock, flags);
962 }
963 
964 static void
l2_st7_got_super(struct FsmInst * fi,int event,void * arg)965 l2_st7_got_super(struct FsmInst *fi, int event, void *arg)
966 {
967 	struct PStack *st = fi->userdata;
968 	struct sk_buff *skb = arg;
969 	int PollFlag, rsp, typ = RR;
970 	unsigned int nr;
971 	struct Layer2 *l2 = &st->l2;
972 
973 	rsp = *skb->data & 0x2;
974 	if (test_bit(FLG_ORIG, &l2->flag))
975 		rsp = !rsp;
976 
977 	skb_pull(skb, l2addrsize(l2));
978 	if (IsRNR(skb->data, st)) {
979 		set_peer_busy(l2);
980 		typ = RNR;
981 	} else
982 		clear_peer_busy(l2);
983 	if (IsREJ(skb->data, st))
984 		typ = REJ;
985 
986 	if (test_bit(FLG_MOD128, &l2->flag)) {
987 		PollFlag = (skb->data[1] & 0x1) == 0x1;
988 		nr = skb->data[1] >> 1;
989 	} else {
990 		PollFlag = (skb->data[0] & 0x10);
991 		nr = (skb->data[0] >> 5) & 0x7;
992 	}
993 	dev_kfree_skb(skb);
994 
995 	if (PollFlag) {
996 		if (rsp)
997 			st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'A');
998 		else
999 			enquiry_response(st);
1000 	}
1001 	if (legalnr(st, nr)) {
1002 		if (typ == REJ) {
1003 			setva(st, nr);
1004 			invoke_retransmission(st, nr);
1005 			stop_t200(st, 10);
1006 			if (FsmAddTimer(&st->l2.t203, st->l2.T203,
1007 					EV_L2_T203, NULL, 6))
1008 				l2m_debug(&st->l2.l2m, "Restart T203 ST7 REJ");
1009 		} else if ((nr == l2->vs) && (typ == RR)) {
1010 			setva(st, nr);
1011 			stop_t200(st, 11);
1012 			FsmRestartTimer(&st->l2.t203, st->l2.T203,
1013 					EV_L2_T203, NULL, 7);
1014 		} else if ((l2->va != nr) || (typ == RNR)) {
1015 			setva(st, nr);
1016 			if (typ != RR) FsmDelTimer(&st->l2.t203, 9);
1017 			restart_t200(st, 12);
1018 		}
1019 		if (!skb_queue_empty(&st->l2.i_queue) && (typ == RR))
1020 			st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
1021 	} else
1022 		nrerrorrecovery(fi);
1023 }
1024 
1025 static void
l2_feed_i_if_reest(struct FsmInst * fi,int event,void * arg)1026 l2_feed_i_if_reest(struct FsmInst *fi, int event, void *arg)
1027 {
1028 	struct PStack *st = fi->userdata;
1029 	struct sk_buff *skb = arg;
1030 
1031 	if (test_bit(FLG_LAPB, &st->l2.flag))
1032 		st->l1.bcs->tx_cnt += skb->len + l2headersize(&st->l2, 0);
1033 	if (!test_bit(FLG_L3_INIT, &st->l2.flag))
1034 		skb_queue_tail(&st->l2.i_queue, skb);
1035 	else
1036 		dev_kfree_skb(skb);
1037 }
1038 
1039 static void
l2_feed_i_pull(struct FsmInst * fi,int event,void * arg)1040 l2_feed_i_pull(struct FsmInst *fi, int event, void *arg)
1041 {
1042 	struct PStack *st = fi->userdata;
1043 	struct sk_buff *skb = arg;
1044 
1045 	if (test_bit(FLG_LAPB, &st->l2.flag))
1046 		st->l1.bcs->tx_cnt += skb->len + l2headersize(&st->l2, 0);
1047 	skb_queue_tail(&st->l2.i_queue, skb);
1048 	st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
1049 }
1050 
1051 static void
l2_feed_iqueue(struct FsmInst * fi,int event,void * arg)1052 l2_feed_iqueue(struct FsmInst *fi, int event, void *arg)
1053 {
1054 	struct PStack *st = fi->userdata;
1055 	struct sk_buff *skb = arg;
1056 
1057 	if (test_bit(FLG_LAPB, &st->l2.flag))
1058 		st->l1.bcs->tx_cnt += skb->len + l2headersize(&st->l2, 0);
1059 	skb_queue_tail(&st->l2.i_queue, skb);
1060 }
1061 
1062 static void
l2_got_iframe(struct FsmInst * fi,int event,void * arg)1063 l2_got_iframe(struct FsmInst *fi, int event, void *arg)
1064 {
1065 	struct PStack *st = fi->userdata;
1066 	struct sk_buff *skb = arg;
1067 	struct Layer2 *l2 = &(st->l2);
1068 	int PollFlag, ns, i;
1069 	unsigned int nr;
1070 
1071 	i = l2addrsize(l2);
1072 	if (test_bit(FLG_MOD128, &l2->flag)) {
1073 		PollFlag = ((skb->data[i + 1] & 0x1) == 0x1);
1074 		ns = skb->data[i] >> 1;
1075 		nr = (skb->data[i + 1] >> 1) & 0x7f;
1076 	} else {
1077 		PollFlag = (skb->data[i] & 0x10);
1078 		ns = (skb->data[i] >> 1) & 0x7;
1079 		nr = (skb->data[i] >> 5) & 0x7;
1080 	}
1081 	if (test_bit(FLG_OWN_BUSY, &l2->flag)) {
1082 		dev_kfree_skb(skb);
1083 		if (PollFlag) enquiry_response(st);
1084 	} else if (l2->vr == ns) {
1085 		(l2->vr)++;
1086 		if (test_bit(FLG_MOD128, &l2->flag))
1087 			l2->vr %= 128;
1088 		else
1089 			l2->vr %= 8;
1090 		test_and_clear_bit(FLG_REJEXC, &l2->flag);
1091 
1092 		if (PollFlag)
1093 			enquiry_response(st);
1094 		else
1095 			test_and_set_bit(FLG_ACK_PEND, &l2->flag);
1096 		skb_pull(skb, l2headersize(l2, 0));
1097 		st->l2.l2l3(st, DL_DATA | INDICATION, skb);
1098 	} else {
1099 		/* n(s)!=v(r) */
1100 		dev_kfree_skb(skb);
1101 		if (test_and_set_bit(FLG_REJEXC, &l2->flag)) {
1102 			if (PollFlag)
1103 				enquiry_response(st);
1104 		} else {
1105 			enquiry_cr(st, REJ, RSP, PollFlag);
1106 			test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
1107 		}
1108 	}
1109 
1110 	if (legalnr(st, nr)) {
1111 		if (!test_bit(FLG_PEER_BUSY, &st->l2.flag) && (fi->state == ST_L2_7)) {
1112 			if (nr == st->l2.vs) {
1113 				stop_t200(st, 13);
1114 				FsmRestartTimer(&st->l2.t203, st->l2.T203,
1115 						EV_L2_T203, NULL, 7);
1116 			} else if (nr != st->l2.va)
1117 				restart_t200(st, 14);
1118 		}
1119 		setva(st, nr);
1120 	} else {
1121 		nrerrorrecovery(fi);
1122 		return;
1123 	}
1124 
1125 	if (!skb_queue_empty(&st->l2.i_queue) && (fi->state == ST_L2_7))
1126 		st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
1127 	if (test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag))
1128 		enquiry_cr(st, RR, RSP, 0);
1129 }
1130 
1131 static void
l2_got_tei(struct FsmInst * fi,int event,void * arg)1132 l2_got_tei(struct FsmInst *fi, int event, void *arg)
1133 {
1134 	struct PStack *st = fi->userdata;
1135 
1136 	st->l2.tei = (long) arg;
1137 
1138 	if (fi->state == ST_L2_3) {
1139 		establishlink(fi);
1140 		test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
1141 	} else
1142 		FsmChangeState(fi, ST_L2_4);
1143 	if (!skb_queue_empty(&st->l2.ui_queue))
1144 		tx_ui(st);
1145 }
1146 
1147 static void
l2_st5_tout_200(struct FsmInst * fi,int event,void * arg)1148 l2_st5_tout_200(struct FsmInst *fi, int event, void *arg)
1149 {
1150 	struct PStack *st = fi->userdata;
1151 
1152 	if (test_bit(FLG_LAPD, &st->l2.flag) &&
1153 	    test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
1154 		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
1155 	} else if (st->l2.rc == st->l2.N200) {
1156 		FsmChangeState(fi, ST_L2_4);
1157 		test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
1158 		skb_queue_purge(&st->l2.i_queue);
1159 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'G');
1160 		if (test_bit(FLG_LAPB, &st->l2.flag))
1161 			st->l2.l2l1(st, PH_DEACTIVATE | REQUEST, NULL);
1162 		st5_dl_release_l2l3(st);
1163 	} else {
1164 		st->l2.rc++;
1165 		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
1166 		send_uframe(st, (test_bit(FLG_MOD128, &st->l2.flag) ? SABME : SABM)
1167 			    | 0x10, CMD);
1168 	}
1169 }
1170 
1171 static void
l2_st6_tout_200(struct FsmInst * fi,int event,void * arg)1172 l2_st6_tout_200(struct FsmInst *fi, int event, void *arg)
1173 {
1174 	struct PStack *st = fi->userdata;
1175 
1176 	if (test_bit(FLG_LAPD, &st->l2.flag) &&
1177 	    test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
1178 		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
1179 	} else if (st->l2.rc == st->l2.N200) {
1180 		FsmChangeState(fi, ST_L2_4);
1181 		test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
1182 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'H');
1183 		lapb_dl_release_l2l3(st, CONFIRM);
1184 	} else {
1185 		st->l2.rc++;
1186 		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200,
1187 			    NULL, 9);
1188 		send_uframe(st, DISC | 0x10, CMD);
1189 	}
1190 }
1191 
1192 static void
l2_st7_tout_200(struct FsmInst * fi,int event,void * arg)1193 l2_st7_tout_200(struct FsmInst *fi, int event, void *arg)
1194 {
1195 	struct PStack *st = fi->userdata;
1196 
1197 	if (test_bit(FLG_LAPD, &st->l2.flag) &&
1198 	    test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
1199 		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
1200 		return;
1201 	}
1202 	test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
1203 	st->l2.rc = 0;
1204 	FsmChangeState(fi, ST_L2_8);
1205 
1206 	transmit_enquiry(st);
1207 	st->l2.rc++;
1208 }
1209 
1210 static void
l2_st8_tout_200(struct FsmInst * fi,int event,void * arg)1211 l2_st8_tout_200(struct FsmInst *fi, int event, void *arg)
1212 {
1213 	struct PStack *st = fi->userdata;
1214 
1215 	if (test_bit(FLG_LAPD, &st->l2.flag) &&
1216 	    test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
1217 		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
1218 		return;
1219 	}
1220 	test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
1221 	if (st->l2.rc == st->l2.N200) {
1222 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'I');
1223 		establishlink(fi);
1224 		test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
1225 	} else {
1226 		transmit_enquiry(st);
1227 		st->l2.rc++;
1228 	}
1229 }
1230 
1231 static void
l2_st7_tout_203(struct FsmInst * fi,int event,void * arg)1232 l2_st7_tout_203(struct FsmInst *fi, int event, void *arg)
1233 {
1234 	struct PStack *st = fi->userdata;
1235 
1236 	if (test_bit(FLG_LAPD, &st->l2.flag) &&
1237 	    test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
1238 		FsmAddTimer(&st->l2.t203, st->l2.T203, EV_L2_T203, NULL, 9);
1239 		return;
1240 	}
1241 	FsmChangeState(fi, ST_L2_8);
1242 	transmit_enquiry(st);
1243 	st->l2.rc = 0;
1244 }
1245 
1246 static void
l2_pull_iqueue(struct FsmInst * fi,int event,void * arg)1247 l2_pull_iqueue(struct FsmInst *fi, int event, void *arg)
1248 {
1249 	struct PStack *st = fi->userdata;
1250 	struct sk_buff *skb, *nskb;
1251 	struct Layer2 *l2 = &st->l2;
1252 	u_char header[MAX_HEADER_LEN];
1253 	int i, hdr_space_needed;
1254 	int unsigned p1;
1255 	u_long flags;
1256 
1257 	if (!cansend(st))
1258 		return;
1259 
1260 	skb = skb_dequeue(&l2->i_queue);
1261 	if (!skb)
1262 		return;
1263 
1264 	hdr_space_needed = l2headersize(l2, 0);
1265 	nskb = skb_realloc_headroom(skb, hdr_space_needed);
1266 	if (!nskb) {
1267 		skb_queue_head(&l2->i_queue, skb);
1268 		return;
1269 	}
1270 	spin_lock_irqsave(&l2->lock, flags);
1271 	if (test_bit(FLG_MOD128, &l2->flag))
1272 		p1 = (l2->vs - l2->va) % 128;
1273 	else
1274 		p1 = (l2->vs - l2->va) % 8;
1275 	p1 = (p1 + l2->sow) % l2->window;
1276 	if (l2->windowar[p1]) {
1277 		printk(KERN_WARNING "isdnl2 try overwrite ack queue entry %d\n",
1278 		       p1);
1279 		dev_kfree_skb(l2->windowar[p1]);
1280 	}
1281 	l2->windowar[p1] = skb;
1282 
1283 	i = sethdraddr(&st->l2, header, CMD);
1284 
1285 	if (test_bit(FLG_MOD128, &l2->flag)) {
1286 		header[i++] = l2->vs << 1;
1287 		header[i++] = l2->vr << 1;
1288 		l2->vs = (l2->vs + 1) % 128;
1289 	} else {
1290 		header[i++] = (l2->vr << 5) | (l2->vs << 1);
1291 		l2->vs = (l2->vs + 1) % 8;
1292 	}
1293 	spin_unlock_irqrestore(&l2->lock, flags);
1294 	memcpy(skb_push(nskb, i), header, i);
1295 	st->l2.l2l1(st, PH_PULL | INDICATION, nskb);
1296 	test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag);
1297 	if (!test_and_set_bit(FLG_T200_RUN, &st->l2.flag)) {
1298 		FsmDelTimer(&st->l2.t203, 13);
1299 		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 11);
1300 	}
1301 	if (!skb_queue_empty(&l2->i_queue) && cansend(st))
1302 		st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
1303 }
1304 
1305 static void
l2_st8_got_super(struct FsmInst * fi,int event,void * arg)1306 l2_st8_got_super(struct FsmInst *fi, int event, void *arg)
1307 {
1308 	struct PStack *st = fi->userdata;
1309 	struct sk_buff *skb = arg;
1310 	int PollFlag, rsp, rnr = 0;
1311 	unsigned int nr;
1312 	struct Layer2 *l2 = &st->l2;
1313 
1314 	rsp = *skb->data & 0x2;
1315 	if (test_bit(FLG_ORIG, &l2->flag))
1316 		rsp = !rsp;
1317 
1318 	skb_pull(skb, l2addrsize(l2));
1319 
1320 	if (IsRNR(skb->data, st)) {
1321 		set_peer_busy(l2);
1322 		rnr = 1;
1323 	} else
1324 		clear_peer_busy(l2);
1325 
1326 	if (test_bit(FLG_MOD128, &l2->flag)) {
1327 		PollFlag = (skb->data[1] & 0x1) == 0x1;
1328 		nr = skb->data[1] >> 1;
1329 	} else {
1330 		PollFlag = (skb->data[0] & 0x10);
1331 		nr = (skb->data[0] >> 5) & 0x7;
1332 	}
1333 	dev_kfree_skb(skb);
1334 
1335 	if (rsp && PollFlag) {
1336 		if (legalnr(st, nr)) {
1337 			if (rnr) {
1338 				restart_t200(st, 15);
1339 			} else {
1340 				stop_t200(st, 16);
1341 				FsmAddTimer(&l2->t203, l2->T203,
1342 					    EV_L2_T203, NULL, 5);
1343 				setva(st, nr);
1344 			}
1345 			invoke_retransmission(st, nr);
1346 			FsmChangeState(fi, ST_L2_7);
1347 			if (!skb_queue_empty(&l2->i_queue) && cansend(st))
1348 				st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
1349 		} else
1350 			nrerrorrecovery(fi);
1351 	} else {
1352 		if (!rsp && PollFlag)
1353 			enquiry_response(st);
1354 		if (legalnr(st, nr)) {
1355 			setva(st, nr);
1356 		} else
1357 			nrerrorrecovery(fi);
1358 	}
1359 }
1360 
1361 static void
l2_got_FRMR(struct FsmInst * fi,int event,void * arg)1362 l2_got_FRMR(struct FsmInst *fi, int event, void *arg)
1363 {
1364 	struct PStack *st = fi->userdata;
1365 	struct sk_buff *skb = arg;
1366 
1367 	skb_pull(skb, l2addrsize(&st->l2) + 1);
1368 
1369 	if (!(skb->data[0] & 1) || ((skb->data[0] & 3) == 1) ||		/* I or S */
1370 	    (IsUA(skb->data) && (fi->state == ST_L2_7))) {
1371 		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'K');
1372 		establishlink(fi);
1373 		test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
1374 	}
1375 	dev_kfree_skb(skb);
1376 }
1377 
1378 static void
l2_st24_tei_remove(struct FsmInst * fi,int event,void * arg)1379 l2_st24_tei_remove(struct FsmInst *fi, int event, void *arg)
1380 {
1381 	struct PStack *st = fi->userdata;
1382 
1383 	skb_queue_purge(&st->l2.ui_queue);
1384 	st->l2.tei = -1;
1385 	FsmChangeState(fi, ST_L2_1);
1386 }
1387 
1388 static void
l2_st3_tei_remove(struct FsmInst * fi,int event,void * arg)1389 l2_st3_tei_remove(struct FsmInst *fi, int event, void *arg)
1390 {
1391 	struct PStack *st = fi->userdata;
1392 
1393 	skb_queue_purge(&st->l2.ui_queue);
1394 	st->l2.tei = -1;
1395 	st->l2.l2l3(st, DL_RELEASE | INDICATION, NULL);
1396 	FsmChangeState(fi, ST_L2_1);
1397 }
1398 
1399 static void
l2_st5_tei_remove(struct FsmInst * fi,int event,void * arg)1400 l2_st5_tei_remove(struct FsmInst *fi, int event, void *arg)
1401 {
1402 	struct PStack *st = fi->userdata;
1403 
1404 	skb_queue_purge(&st->l2.i_queue);
1405 	skb_queue_purge(&st->l2.ui_queue);
1406 	freewin(st);
1407 	st->l2.tei = -1;
1408 	stop_t200(st, 17);
1409 	st5_dl_release_l2l3(st);
1410 	FsmChangeState(fi, ST_L2_1);
1411 }
1412 
1413 static void
l2_st6_tei_remove(struct FsmInst * fi,int event,void * arg)1414 l2_st6_tei_remove(struct FsmInst *fi, int event, void *arg)
1415 {
1416 	struct PStack *st = fi->userdata;
1417 
1418 	skb_queue_purge(&st->l2.ui_queue);
1419 	st->l2.tei = -1;
1420 	stop_t200(st, 18);
1421 	st->l2.l2l3(st, DL_RELEASE | CONFIRM, NULL);
1422 	FsmChangeState(fi, ST_L2_1);
1423 }
1424 
1425 static void
l2_tei_remove(struct FsmInst * fi,int event,void * arg)1426 l2_tei_remove(struct FsmInst *fi, int event, void *arg)
1427 {
1428 	struct PStack *st = fi->userdata;
1429 
1430 	skb_queue_purge(&st->l2.i_queue);
1431 	skb_queue_purge(&st->l2.ui_queue);
1432 	freewin(st);
1433 	st->l2.tei = -1;
1434 	stop_t200(st, 17);
1435 	FsmDelTimer(&st->l2.t203, 19);
1436 	st->l2.l2l3(st, DL_RELEASE | INDICATION, NULL);
1437 	FsmChangeState(fi, ST_L2_1);
1438 }
1439 
1440 static void
l2_st14_persistent_da(struct FsmInst * fi,int event,void * arg)1441 l2_st14_persistent_da(struct FsmInst *fi, int event, void *arg)
1442 {
1443 	struct PStack *st = fi->userdata;
1444 
1445 	skb_queue_purge(&st->l2.i_queue);
1446 	skb_queue_purge(&st->l2.ui_queue);
1447 	if (test_and_clear_bit(FLG_ESTAB_PEND, &st->l2.flag))
1448 		st->l2.l2l3(st, DL_RELEASE | INDICATION, NULL);
1449 }
1450 
1451 static void
l2_st5_persistent_da(struct FsmInst * fi,int event,void * arg)1452 l2_st5_persistent_da(struct FsmInst *fi, int event, void *arg)
1453 {
1454 	struct PStack *st = fi->userdata;
1455 
1456 	skb_queue_purge(&st->l2.i_queue);
1457 	skb_queue_purge(&st->l2.ui_queue);
1458 	freewin(st);
1459 	stop_t200(st, 19);
1460 	st5_dl_release_l2l3(st);
1461 	FsmChangeState(fi, ST_L2_4);
1462 }
1463 
1464 static void
l2_st6_persistent_da(struct FsmInst * fi,int event,void * arg)1465 l2_st6_persistent_da(struct FsmInst *fi, int event, void *arg)
1466 {
1467 	struct PStack *st = fi->userdata;
1468 
1469 	skb_queue_purge(&st->l2.ui_queue);
1470 	stop_t200(st, 20);
1471 	st->l2.l2l3(st, DL_RELEASE | CONFIRM, NULL);
1472 	FsmChangeState(fi, ST_L2_4);
1473 }
1474 
1475 static void
l2_persistent_da(struct FsmInst * fi,int event,void * arg)1476 l2_persistent_da(struct FsmInst *fi, int event, void *arg)
1477 {
1478 	struct PStack *st = fi->userdata;
1479 
1480 	skb_queue_purge(&st->l2.i_queue);
1481 	skb_queue_purge(&st->l2.ui_queue);
1482 	freewin(st);
1483 	stop_t200(st, 19);
1484 	FsmDelTimer(&st->l2.t203, 19);
1485 	st->l2.l2l3(st, DL_RELEASE | INDICATION, NULL);
1486 	FsmChangeState(fi, ST_L2_4);
1487 }
1488 
1489 static void
l2_set_own_busy(struct FsmInst * fi,int event,void * arg)1490 l2_set_own_busy(struct FsmInst *fi, int event, void *arg)
1491 {
1492 	struct PStack *st = fi->userdata;
1493 
1494 	if (!test_and_set_bit(FLG_OWN_BUSY, &st->l2.flag)) {
1495 		enquiry_cr(st, RNR, RSP, 0);
1496 		test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag);
1497 	}
1498 }
1499 
1500 static void
l2_clear_own_busy(struct FsmInst * fi,int event,void * arg)1501 l2_clear_own_busy(struct FsmInst *fi, int event, void *arg)
1502 {
1503 	struct PStack *st = fi->userdata;
1504 
1505 	if (!test_and_clear_bit(FLG_OWN_BUSY, &st->l2.flag)) {
1506 		enquiry_cr(st, RR, RSP, 0);
1507 		test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag);
1508 	}
1509 }
1510 
1511 static void
l2_frame_error(struct FsmInst * fi,int event,void * arg)1512 l2_frame_error(struct FsmInst *fi, int event, void *arg)
1513 {
1514 	struct PStack *st = fi->userdata;
1515 
1516 	st->ma.layer(st, MDL_ERROR | INDICATION, arg);
1517 }
1518 
1519 static void
l2_frame_error_reest(struct FsmInst * fi,int event,void * arg)1520 l2_frame_error_reest(struct FsmInst *fi, int event, void *arg)
1521 {
1522 	struct PStack *st = fi->userdata;
1523 
1524 	st->ma.layer(st, MDL_ERROR | INDICATION, arg);
1525 	establishlink(fi);
1526 	test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
1527 }
1528 
1529 static struct FsmNode L2FnList[] __initdata =
1530 {
1531 	{ST_L2_1, EV_L2_DL_ESTABLISH_REQ, l2_mdl_assign},
1532 	{ST_L2_2, EV_L2_DL_ESTABLISH_REQ, l2_go_st3},
1533 	{ST_L2_4, EV_L2_DL_ESTABLISH_REQ, l2_establish},
1534 	{ST_L2_5, EV_L2_DL_ESTABLISH_REQ, l2_discard_i_setl3},
1535 	{ST_L2_7, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
1536 	{ST_L2_8, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
1537 	{ST_L2_4, EV_L2_DL_RELEASE_REQ, l2_release},
1538 	{ST_L2_5, EV_L2_DL_RELEASE_REQ, l2_pend_rel},
1539 	{ST_L2_7, EV_L2_DL_RELEASE_REQ, l2_disconnect},
1540 	{ST_L2_8, EV_L2_DL_RELEASE_REQ, l2_disconnect},
1541 	{ST_L2_5, EV_L2_DL_DATA, l2_feed_i_if_reest},
1542 	{ST_L2_7, EV_L2_DL_DATA, l2_feed_i_pull},
1543 	{ST_L2_8, EV_L2_DL_DATA, l2_feed_iqueue},
1544 	{ST_L2_1, EV_L2_DL_UNIT_DATA, l2_queue_ui_assign},
1545 	{ST_L2_2, EV_L2_DL_UNIT_DATA, l2_queue_ui},
1546 	{ST_L2_3, EV_L2_DL_UNIT_DATA, l2_queue_ui},
1547 	{ST_L2_4, EV_L2_DL_UNIT_DATA, l2_send_ui},
1548 	{ST_L2_5, EV_L2_DL_UNIT_DATA, l2_send_ui},
1549 	{ST_L2_6, EV_L2_DL_UNIT_DATA, l2_send_ui},
1550 	{ST_L2_7, EV_L2_DL_UNIT_DATA, l2_send_ui},
1551 	{ST_L2_8, EV_L2_DL_UNIT_DATA, l2_send_ui},
1552 	{ST_L2_1, EV_L2_MDL_ASSIGN, l2_got_tei},
1553 	{ST_L2_2, EV_L2_MDL_ASSIGN, l2_got_tei},
1554 	{ST_L2_3, EV_L2_MDL_ASSIGN, l2_got_tei},
1555 	{ST_L2_2, EV_L2_MDL_ERROR, l2_st24_tei_remove},
1556 	{ST_L2_3, EV_L2_MDL_ERROR, l2_st3_tei_remove},
1557 	{ST_L2_4, EV_L2_MDL_REMOVE, l2_st24_tei_remove},
1558 	{ST_L2_5, EV_L2_MDL_REMOVE, l2_st5_tei_remove},
1559 	{ST_L2_6, EV_L2_MDL_REMOVE, l2_st6_tei_remove},
1560 	{ST_L2_7, EV_L2_MDL_REMOVE, l2_tei_remove},
1561 	{ST_L2_8, EV_L2_MDL_REMOVE, l2_tei_remove},
1562 	{ST_L2_4, EV_L2_SABME, l2_start_multi},
1563 	{ST_L2_5, EV_L2_SABME, l2_send_UA},
1564 	{ST_L2_6, EV_L2_SABME, l2_send_DM},
1565 	{ST_L2_7, EV_L2_SABME, l2_restart_multi},
1566 	{ST_L2_8, EV_L2_SABME, l2_restart_multi},
1567 	{ST_L2_4, EV_L2_DISC, l2_send_DM},
1568 	{ST_L2_5, EV_L2_DISC, l2_send_DM},
1569 	{ST_L2_6, EV_L2_DISC, l2_send_UA},
1570 	{ST_L2_7, EV_L2_DISC, l2_stop_multi},
1571 	{ST_L2_8, EV_L2_DISC, l2_stop_multi},
1572 	{ST_L2_4, EV_L2_UA, l2_mdl_error_ua},
1573 	{ST_L2_5, EV_L2_UA, l2_connected},
1574 	{ST_L2_6, EV_L2_UA, l2_released},
1575 	{ST_L2_7, EV_L2_UA, l2_mdl_error_ua},
1576 	{ST_L2_8, EV_L2_UA, l2_mdl_error_ua},
1577 	{ST_L2_4, EV_L2_DM, l2_reestablish},
1578 	{ST_L2_5, EV_L2_DM, l2_st5_dm_release},
1579 	{ST_L2_6, EV_L2_DM, l2_st6_dm_release},
1580 	{ST_L2_7, EV_L2_DM, l2_mdl_error_dm},
1581 	{ST_L2_8, EV_L2_DM, l2_st8_mdl_error_dm},
1582 	{ST_L2_1, EV_L2_UI, l2_got_ui},
1583 	{ST_L2_2, EV_L2_UI, l2_got_ui},
1584 	{ST_L2_3, EV_L2_UI, l2_got_ui},
1585 	{ST_L2_4, EV_L2_UI, l2_got_ui},
1586 	{ST_L2_5, EV_L2_UI, l2_got_ui},
1587 	{ST_L2_6, EV_L2_UI, l2_got_ui},
1588 	{ST_L2_7, EV_L2_UI, l2_got_ui},
1589 	{ST_L2_8, EV_L2_UI, l2_got_ui},
1590 	{ST_L2_7, EV_L2_FRMR, l2_got_FRMR},
1591 	{ST_L2_8, EV_L2_FRMR, l2_got_FRMR},
1592 	{ST_L2_7, EV_L2_SUPER, l2_st7_got_super},
1593 	{ST_L2_8, EV_L2_SUPER, l2_st8_got_super},
1594 	{ST_L2_7, EV_L2_I, l2_got_iframe},
1595 	{ST_L2_8, EV_L2_I, l2_got_iframe},
1596 	{ST_L2_5, EV_L2_T200, l2_st5_tout_200},
1597 	{ST_L2_6, EV_L2_T200, l2_st6_tout_200},
1598 	{ST_L2_7, EV_L2_T200, l2_st7_tout_200},
1599 	{ST_L2_8, EV_L2_T200, l2_st8_tout_200},
1600 	{ST_L2_7, EV_L2_T203, l2_st7_tout_203},
1601 	{ST_L2_7, EV_L2_ACK_PULL, l2_pull_iqueue},
1602 	{ST_L2_7, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
1603 	{ST_L2_8, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
1604 	{ST_L2_7, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
1605 	{ST_L2_8, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
1606 	{ST_L2_4, EV_L2_FRAME_ERROR, l2_frame_error},
1607 	{ST_L2_5, EV_L2_FRAME_ERROR, l2_frame_error},
1608 	{ST_L2_6, EV_L2_FRAME_ERROR, l2_frame_error},
1609 	{ST_L2_7, EV_L2_FRAME_ERROR, l2_frame_error_reest},
1610 	{ST_L2_8, EV_L2_FRAME_ERROR, l2_frame_error_reest},
1611 	{ST_L2_1, EV_L1_DEACTIVATE, l2_st14_persistent_da},
1612 	{ST_L2_2, EV_L1_DEACTIVATE, l2_st24_tei_remove},
1613 	{ST_L2_3, EV_L1_DEACTIVATE, l2_st3_tei_remove},
1614 	{ST_L2_4, EV_L1_DEACTIVATE, l2_st14_persistent_da},
1615 	{ST_L2_5, EV_L1_DEACTIVATE, l2_st5_persistent_da},
1616 	{ST_L2_6, EV_L1_DEACTIVATE, l2_st6_persistent_da},
1617 	{ST_L2_7, EV_L1_DEACTIVATE, l2_persistent_da},
1618 	{ST_L2_8, EV_L1_DEACTIVATE, l2_persistent_da},
1619 };
1620 
1621 static void
isdnl2_l1l2(struct PStack * st,int pr,void * arg)1622 isdnl2_l1l2(struct PStack *st, int pr, void *arg)
1623 {
1624 	struct sk_buff *skb = arg;
1625 	u_char *datap;
1626 	int ret = 1, len;
1627 	int c = 0;
1628 
1629 	switch (pr) {
1630 	case (PH_DATA | INDICATION):
1631 		datap = skb->data;
1632 		len = l2addrsize(&st->l2);
1633 		if (skb->len > len)
1634 			datap += len;
1635 		else {
1636 			FsmEvent(&st->l2.l2m, EV_L2_FRAME_ERROR, (void *) 'N');
1637 			dev_kfree_skb(skb);
1638 			return;
1639 		}
1640 		if (!(*datap & 1)) {	/* I-Frame */
1641 			if (!(c = iframe_error(st, skb)))
1642 				ret = FsmEvent(&st->l2.l2m, EV_L2_I, skb);
1643 		} else if (IsSFrame(datap, st)) {	/* S-Frame */
1644 			if (!(c = super_error(st, skb)))
1645 				ret = FsmEvent(&st->l2.l2m, EV_L2_SUPER, skb);
1646 		} else if (IsUI(datap)) {
1647 			if (!(c = UI_error(st, skb)))
1648 				ret = FsmEvent(&st->l2.l2m, EV_L2_UI, skb);
1649 		} else if (IsSABME(datap, st)) {
1650 			if (!(c = unnum_error(st, skb, CMD)))
1651 				ret = FsmEvent(&st->l2.l2m, EV_L2_SABME, skb);
1652 		} else if (IsUA(datap)) {
1653 			if (!(c = unnum_error(st, skb, RSP)))
1654 				ret = FsmEvent(&st->l2.l2m, EV_L2_UA, skb);
1655 		} else if (IsDISC(datap)) {
1656 			if (!(c = unnum_error(st, skb, CMD)))
1657 				ret = FsmEvent(&st->l2.l2m, EV_L2_DISC, skb);
1658 		} else if (IsDM(datap)) {
1659 			if (!(c = unnum_error(st, skb, RSP)))
1660 				ret = FsmEvent(&st->l2.l2m, EV_L2_DM, skb);
1661 		} else if (IsFRMR(datap)) {
1662 			if (!(c = FRMR_error(st, skb)))
1663 				ret = FsmEvent(&st->l2.l2m, EV_L2_FRMR, skb);
1664 		} else {
1665 			FsmEvent(&st->l2.l2m, EV_L2_FRAME_ERROR, (void *) 'L');
1666 			dev_kfree_skb(skb);
1667 			ret = 0;
1668 		}
1669 		if (c) {
1670 			dev_kfree_skb(skb);
1671 			FsmEvent(&st->l2.l2m, EV_L2_FRAME_ERROR, (void *)(long)c);
1672 			ret = 0;
1673 		}
1674 		if (ret)
1675 			dev_kfree_skb(skb);
1676 		break;
1677 	case (PH_PULL | CONFIRM):
1678 		FsmEvent(&st->l2.l2m, EV_L2_ACK_PULL, arg);
1679 		break;
1680 	case (PH_PAUSE | INDICATION):
1681 		test_and_set_bit(FLG_DCHAN_BUSY, &st->l2.flag);
1682 		break;
1683 	case (PH_PAUSE | CONFIRM):
1684 		test_and_clear_bit(FLG_DCHAN_BUSY, &st->l2.flag);
1685 		break;
1686 	case (PH_ACTIVATE | CONFIRM):
1687 	case (PH_ACTIVATE | INDICATION):
1688 		test_and_set_bit(FLG_L1_ACTIV, &st->l2.flag);
1689 		if (test_and_clear_bit(FLG_ESTAB_PEND, &st->l2.flag))
1690 			FsmEvent(&st->l2.l2m, EV_L2_DL_ESTABLISH_REQ, arg);
1691 		break;
1692 	case (PH_DEACTIVATE | INDICATION):
1693 	case (PH_DEACTIVATE | CONFIRM):
1694 		test_and_clear_bit(FLG_L1_ACTIV, &st->l2.flag);
1695 		FsmEvent(&st->l2.l2m, EV_L1_DEACTIVATE, arg);
1696 		break;
1697 	default:
1698 		l2m_debug(&st->l2.l2m, "l2 unknown pr %04x", pr);
1699 		break;
1700 	}
1701 }
1702 
1703 static void
isdnl2_l3l2(struct PStack * st,int pr,void * arg)1704 isdnl2_l3l2(struct PStack *st, int pr, void *arg)
1705 {
1706 	switch (pr) {
1707 	case (DL_DATA | REQUEST):
1708 		if (FsmEvent(&st->l2.l2m, EV_L2_DL_DATA, arg)) {
1709 			dev_kfree_skb((struct sk_buff *) arg);
1710 		}
1711 		break;
1712 	case (DL_UNIT_DATA | REQUEST):
1713 		if (FsmEvent(&st->l2.l2m, EV_L2_DL_UNIT_DATA, arg)) {
1714 			dev_kfree_skb((struct sk_buff *) arg);
1715 		}
1716 		break;
1717 	case (DL_ESTABLISH | REQUEST):
1718 		if (test_bit(FLG_L1_ACTIV, &st->l2.flag)) {
1719 			if (test_bit(FLG_LAPD, &st->l2.flag) ||
1720 			    test_bit(FLG_ORIG, &st->l2.flag)) {
1721 				FsmEvent(&st->l2.l2m, EV_L2_DL_ESTABLISH_REQ, arg);
1722 			}
1723 		} else {
1724 			if (test_bit(FLG_LAPD, &st->l2.flag) ||
1725 			    test_bit(FLG_ORIG, &st->l2.flag)) {
1726 				test_and_set_bit(FLG_ESTAB_PEND, &st->l2.flag);
1727 			}
1728 			st->l2.l2l1(st, PH_ACTIVATE, NULL);
1729 		}
1730 		break;
1731 	case (DL_RELEASE | REQUEST):
1732 		if (test_bit(FLG_LAPB, &st->l2.flag)) {
1733 			st->l2.l2l1(st, PH_DEACTIVATE, NULL);
1734 		}
1735 		FsmEvent(&st->l2.l2m, EV_L2_DL_RELEASE_REQ, arg);
1736 		break;
1737 	case (MDL_ASSIGN | REQUEST):
1738 		FsmEvent(&st->l2.l2m, EV_L2_MDL_ASSIGN, arg);
1739 		break;
1740 	case (MDL_REMOVE | REQUEST):
1741 		FsmEvent(&st->l2.l2m, EV_L2_MDL_REMOVE, arg);
1742 		break;
1743 	case (MDL_ERROR | RESPONSE):
1744 		FsmEvent(&st->l2.l2m, EV_L2_MDL_ERROR, arg);
1745 		break;
1746 	}
1747 }
1748 
1749 void
releasestack_isdnl2(struct PStack * st)1750 releasestack_isdnl2(struct PStack *st)
1751 {
1752 	FsmDelTimer(&st->l2.t200, 21);
1753 	FsmDelTimer(&st->l2.t203, 16);
1754 	skb_queue_purge(&st->l2.i_queue);
1755 	skb_queue_purge(&st->l2.ui_queue);
1756 	ReleaseWin(&st->l2);
1757 }
1758 
1759 static void
l2m_debug(struct FsmInst * fi,char * fmt,...)1760 l2m_debug(struct FsmInst *fi, char *fmt, ...)
1761 {
1762 	va_list args;
1763 	struct PStack *st = fi->userdata;
1764 
1765 	va_start(args, fmt);
1766 	VHiSax_putstatus(st->l1.hardware, st->l2.debug_id, fmt, args);
1767 	va_end(args);
1768 }
1769 
1770 void
setstack_isdnl2(struct PStack * st,char * debug_id)1771 setstack_isdnl2(struct PStack *st, char *debug_id)
1772 {
1773 	spin_lock_init(&st->l2.lock);
1774 	st->l1.l1l2 = isdnl2_l1l2;
1775 	st->l3.l3l2 = isdnl2_l3l2;
1776 
1777 	skb_queue_head_init(&st->l2.i_queue);
1778 	skb_queue_head_init(&st->l2.ui_queue);
1779 	InitWin(&st->l2);
1780 	st->l2.debug = 0;
1781 
1782 	st->l2.l2m.fsm = &l2fsm;
1783 	if (test_bit(FLG_LAPB, &st->l2.flag))
1784 		st->l2.l2m.state = ST_L2_4;
1785 	else
1786 		st->l2.l2m.state = ST_L2_1;
1787 	st->l2.l2m.debug = 0;
1788 	st->l2.l2m.userdata = st;
1789 	st->l2.l2m.userint = 0;
1790 	st->l2.l2m.printdebug = l2m_debug;
1791 	strcpy(st->l2.debug_id, debug_id);
1792 
1793 	FsmInitTimer(&st->l2.l2m, &st->l2.t200);
1794 	FsmInitTimer(&st->l2.l2m, &st->l2.t203);
1795 }
1796 
1797 static void
transl2_l3l2(struct PStack * st,int pr,void * arg)1798 transl2_l3l2(struct PStack *st, int pr, void *arg)
1799 {
1800 	switch (pr) {
1801 	case (DL_DATA | REQUEST):
1802 	case (DL_UNIT_DATA | REQUEST):
1803 		st->l2.l2l1(st, PH_DATA | REQUEST, arg);
1804 		break;
1805 	case (DL_ESTABLISH | REQUEST):
1806 		st->l2.l2l1(st, PH_ACTIVATE | REQUEST, NULL);
1807 		break;
1808 	case (DL_RELEASE | REQUEST):
1809 		st->l2.l2l1(st, PH_DEACTIVATE | REQUEST, NULL);
1810 		break;
1811 	}
1812 }
1813 
1814 void
setstack_transl2(struct PStack * st)1815 setstack_transl2(struct PStack *st)
1816 {
1817 	st->l3.l3l2 = transl2_l3l2;
1818 }
1819 
1820 void
releasestack_transl2(struct PStack * st)1821 releasestack_transl2(struct PStack *st)
1822 {
1823 }
1824 
1825 int __init
Isdnl2New(void)1826 Isdnl2New(void)
1827 {
1828 	l2fsm.state_count = L2_STATE_COUNT;
1829 	l2fsm.event_count = L2_EVENT_COUNT;
1830 	l2fsm.strEvent = strL2Event;
1831 	l2fsm.strState = strL2State;
1832 	return FsmNew(&l2fsm, L2FnList, ARRAY_SIZE(L2FnList));
1833 }
1834 
1835 void
Isdnl2Free(void)1836 Isdnl2Free(void)
1837 {
1838 	FsmFree(&l2fsm);
1839 }
1840