[NET]: Transform skb_queue_len() binary tests into skb_queue_empty()
[linux-3.10.git] / drivers / isdn / hisax / isdnl3.c
1 /* $Id: isdnl3.c,v 2.22.2.3 2004/01/13 14:31:25 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 "hisax.h"
20 #include "isdnl3.h"
21 #include <linux/config.h>
22
23 const char *l3_revision = "$Revision: 2.22.2.3 $";
24
25 static struct Fsm l3fsm;
26
27 enum {
28         ST_L3_LC_REL,
29         ST_L3_LC_ESTAB_WAIT,
30         ST_L3_LC_REL_DELAY, 
31         ST_L3_LC_REL_WAIT,
32         ST_L3_LC_ESTAB,
33 };
34
35 #define L3_STATE_COUNT (ST_L3_LC_ESTAB+1)
36
37 static char *strL3State[] =
38 {
39         "ST_L3_LC_REL",
40         "ST_L3_LC_ESTAB_WAIT",
41         "ST_L3_LC_REL_DELAY",
42         "ST_L3_LC_REL_WAIT",
43         "ST_L3_LC_ESTAB",
44 };
45
46 enum {
47         EV_ESTABLISH_REQ,
48         EV_ESTABLISH_IND,
49         EV_ESTABLISH_CNF,
50         EV_RELEASE_REQ,
51         EV_RELEASE_CNF,
52         EV_RELEASE_IND,
53         EV_TIMEOUT,
54 };
55
56 #define L3_EVENT_COUNT (EV_TIMEOUT+1)
57
58 static char *strL3Event[] =
59 {
60         "EV_ESTABLISH_REQ",
61         "EV_ESTABLISH_IND",
62         "EV_ESTABLISH_CNF",
63         "EV_RELEASE_REQ",
64         "EV_RELEASE_CNF",
65         "EV_RELEASE_IND",
66         "EV_TIMEOUT",
67 };
68
69 static void
70 l3m_debug(struct FsmInst *fi, char *fmt, ...)
71 {
72         va_list args;
73         struct PStack *st = fi->userdata;
74
75         va_start(args, fmt);
76         VHiSax_putstatus(st->l1.hardware, st->l3.debug_id, fmt, args);
77         va_end(args);
78 }
79
80 u_char *
81 findie(u_char * p, int size, u_char ie, int wanted_set)
82 {
83         int l, codeset, maincodeset;
84         u_char *pend = p + size;
85
86         /* skip protocol discriminator, callref and message type */
87         p++;
88         l = (*p++) & 0xf;
89         p += l;
90         p++;
91         codeset = 0;
92         maincodeset = 0;
93         /* while there are bytes left... */
94         while (p < pend) {
95                 if ((*p & 0xf0) == 0x90) {
96                         codeset = *p & 0x07;
97                         if (!(*p & 0x08))
98                                 maincodeset = codeset;
99                 }
100                 if (*p & 0x80)
101                         p++;
102                 else {
103                         if (codeset == wanted_set) {
104                                 if (*p == ie)
105                                   { /* improved length check (Werner Cornelius) */
106                                     if ((pend - p) < 2) 
107                                       return(NULL); 
108                                     if (*(p+1) > (pend - (p+2))) 
109                                       return(NULL); 
110                                     return (p);
111                                   }           
112                                   
113                                 if (*p > ie)
114                                         return (NULL);
115                         }
116                         p++;
117                         l = *p++;
118                         p += l;
119                         codeset = maincodeset;
120                 }
121         }
122         return (NULL);
123 }
124
125 int
126 getcallref(u_char * p)
127 {
128         int l, cr = 0;
129
130         p++;                    /* prot discr */
131         if (*p & 0xfe)          /* wrong callref BRI only 1 octet*/
132                 return(-2);
133         l = 0xf & *p++;         /* callref length */
134         if (!l)                 /* dummy CallRef */
135                 return(-1);
136         cr = *p++;
137         return (cr);
138 }
139
140 static int OrigCallRef = 0;
141
142 int
143 newcallref(void)
144 {
145         if (OrigCallRef == 127)
146                 OrigCallRef = 1;
147         else
148                 OrigCallRef++;
149         return (OrigCallRef);
150 }
151
152 void
153 newl3state(struct l3_process *pc, int state)
154 {
155         if (pc->debug & L3_DEB_STATE)
156                 l3_debug(pc->st, "newstate cr %d %d --> %d", 
157                          pc->callref & 0x7F,
158                          pc->state, state);
159         pc->state = state;
160 }
161
162 static void
163 L3ExpireTimer(struct L3Timer *t)
164 {
165         t->pc->st->lli.l4l3(t->pc->st, t->event, t->pc);
166 }
167
168 void
169 L3InitTimer(struct l3_process *pc, struct L3Timer *t)
170 {
171         t->pc = pc;
172         t->tl.function = (void *) L3ExpireTimer;
173         t->tl.data = (long) t;
174         init_timer(&t->tl);
175 }
176
177 void
178 L3DelTimer(struct L3Timer *t)
179 {
180         del_timer(&t->tl);
181 }
182
183 int
184 L3AddTimer(struct L3Timer *t,
185            int millisec, int event)
186 {
187         if (timer_pending(&t->tl)) {
188                 printk(KERN_WARNING "L3AddTimer: timer already active!\n");
189                 return -1;
190         }
191         init_timer(&t->tl);
192         t->event = event;
193         t->tl.expires = jiffies + (millisec * HZ) / 1000;
194         add_timer(&t->tl);
195         return 0;
196 }
197
198 void
199 StopAllL3Timer(struct l3_process *pc)
200 {
201         L3DelTimer(&pc->timer);
202 }
203
204 struct sk_buff *
205 l3_alloc_skb(int len)
206 {
207         struct sk_buff *skb;
208
209         if (!(skb = alloc_skb(len + MAX_HEADER_LEN, GFP_ATOMIC))) {
210                 printk(KERN_WARNING "HiSax: No skb for D-channel\n");
211                 return (NULL);
212         }
213         skb_reserve(skb, MAX_HEADER_LEN);
214         return (skb);
215 }
216
217 static void
218 no_l3_proto(struct PStack *st, int pr, void *arg)
219 {
220         struct sk_buff *skb = arg;
221
222         HiSax_putstatus(st->l1.hardware, "L3", "no D protocol");
223         if (skb) {
224                 dev_kfree_skb(skb);
225         }
226 }
227
228 static int
229 no_l3_proto_spec(struct PStack *st, isdn_ctrl *ic)
230 {
231         printk(KERN_WARNING "HiSax: no specific protocol handler for proto %lu\n",ic->arg & 0xFF);
232         return(-1);
233 }
234
235 #ifdef  CONFIG_HISAX_EURO
236 extern void setstack_dss1(struct PStack *st);
237 #endif
238
239 #ifdef  CONFIG_HISAX_NI1
240 extern void setstack_ni1(struct PStack *st);
241 #endif
242
243 #ifdef  CONFIG_HISAX_1TR6
244 extern void setstack_1tr6(struct PStack *st);
245 #endif
246
247 struct l3_process
248 *getl3proc(struct PStack *st, int cr)
249 {
250         struct l3_process *p = st->l3.proc;
251
252         while (p)
253                 if (p->callref == cr)
254                         return (p);
255                 else
256                         p = p->next;
257         return (NULL);
258 }
259
260 struct l3_process
261 *new_l3_process(struct PStack *st, int cr)
262 {
263         struct l3_process *p, *np;
264
265         if (!(p = kmalloc(sizeof(struct l3_process), GFP_ATOMIC))) {
266                 printk(KERN_ERR "HiSax can't get memory for cr %d\n", cr);
267                 return (NULL);
268         }
269         if (!st->l3.proc)
270                 st->l3.proc = p;
271         else {
272                 np = st->l3.proc;
273                 while (np->next)
274                         np = np->next;
275                 np->next = p;
276         }
277         p->next = NULL;
278         p->debug = st->l3.debug;
279         p->callref = cr;
280         p->state = 0;
281         p->chan = NULL;
282         p->st = st;
283         p->N303 = st->l3.N303;
284         L3InitTimer(p, &p->timer);
285         return (p);
286 };
287
288 void
289 release_l3_process(struct l3_process *p)
290 {
291         struct l3_process *np, *pp = NULL;
292
293         if (!p)
294                 return;
295         np = p->st->l3.proc;
296         while (np) {
297                 if (np == p) {
298                         StopAllL3Timer(p);
299                         if (pp)
300                                 pp->next = np->next;
301                         else if (!(p->st->l3.proc = np->next) &&
302                                 !test_bit(FLG_PTP, &p->st->l2.flag)) {
303                                 if (p->debug)
304                                         l3_debug(p->st, "release_l3_process: last process");
305                                 if (skb_queue_empty(&p->st->l3.squeue)) {
306                                         if (p->debug)
307                                                 l3_debug(p->st, "release_l3_process: release link");
308                                         if (p->st->protocol != ISDN_PTYPE_NI1)
309                                                 FsmEvent(&p->st->l3.l3m, EV_RELEASE_REQ, NULL);
310                                         else
311                                                 FsmEvent(&p->st->l3.l3m, EV_RELEASE_IND, NULL);
312                                 } else {
313                                         if (p->debug)
314                                                 l3_debug(p->st, "release_l3_process: not release link");
315                                 }
316                         } 
317                         kfree(p);
318                         return;
319                 }
320                 pp = np;
321                 np = np->next;
322         }
323         printk(KERN_ERR "HiSax internal L3 error CR(%d) not in list\n", p->callref);
324         l3_debug(p->st, "HiSax internal L3 error CR(%d) not in list", p->callref);
325 };
326
327 static void
328 l3ml3p(struct PStack *st, int pr)
329 {
330         struct l3_process *p = st->l3.proc;
331         struct l3_process *np;
332
333         while (p) {
334                 /* p might be kfreed under us, so we need to save where we want to go on */
335                 np = p->next;
336                 st->l3.l3ml3(st, pr, p);
337                 p = np;
338         }
339 }
340
341 void
342 setstack_l3dc(struct PStack *st, struct Channel *chanp)
343 {
344         char tmp[64];
345
346         st->l3.proc   = NULL;
347         st->l3.global = NULL;
348         skb_queue_head_init(&st->l3.squeue);
349         st->l3.l3m.fsm = &l3fsm;
350         st->l3.l3m.state = ST_L3_LC_REL;
351         st->l3.l3m.debug = 1;
352         st->l3.l3m.userdata = st;
353         st->l3.l3m.userint = 0;
354         st->l3.l3m.printdebug = l3m_debug;
355         FsmInitTimer(&st->l3.l3m, &st->l3.l3m_timer);
356         strcpy(st->l3.debug_id, "L3DC ");
357         st->lli.l4l3_proto = no_l3_proto_spec;
358
359 #ifdef  CONFIG_HISAX_EURO
360         if (st->protocol == ISDN_PTYPE_EURO) {
361                 setstack_dss1(st);
362         } else
363 #endif
364 #ifdef  CONFIG_HISAX_NI1
365         if (st->protocol == ISDN_PTYPE_NI1) {
366                 setstack_ni1(st);
367         } else
368 #endif
369 #ifdef  CONFIG_HISAX_1TR6
370         if (st->protocol == ISDN_PTYPE_1TR6) {
371                 setstack_1tr6(st);
372         } else
373 #endif
374         if (st->protocol == ISDN_PTYPE_LEASED) {
375                 st->lli.l4l3 = no_l3_proto;
376                 st->l2.l2l3 = no_l3_proto;
377                 st->l3.l3ml3 = no_l3_proto;
378                 printk(KERN_INFO "HiSax: Leased line mode\n");
379         } else {
380                 st->lli.l4l3 = no_l3_proto;
381                 st->l2.l2l3 = no_l3_proto;
382                 st->l3.l3ml3 = no_l3_proto;
383                 sprintf(tmp, "protocol %s not supported",
384                         (st->protocol == ISDN_PTYPE_1TR6) ? "1tr6" :
385                         (st->protocol == ISDN_PTYPE_EURO) ? "euro" :
386                         (st->protocol == ISDN_PTYPE_NI1) ? "ni1" :
387                         "unknown");
388                 printk(KERN_WARNING "HiSax: %s\n", tmp);
389                 st->protocol = -1;
390         }
391 }
392
393 static void
394 isdnl3_trans(struct PStack *st, int pr, void *arg) {
395         st->l3.l3l2(st, pr, arg);
396 }
397
398 void
399 releasestack_isdnl3(struct PStack *st)
400 {
401         while (st->l3.proc)
402                 release_l3_process(st->l3.proc);
403         if (st->l3.global) {
404                 StopAllL3Timer(st->l3.global);
405                 kfree(st->l3.global);
406                 st->l3.global = NULL;
407         }
408         FsmDelTimer(&st->l3.l3m_timer, 54);
409         skb_queue_purge(&st->l3.squeue);
410 }
411
412 void
413 setstack_l3bc(struct PStack *st, struct Channel *chanp)
414 {
415
416         st->l3.proc   = NULL;
417         st->l3.global = NULL;
418         skb_queue_head_init(&st->l3.squeue);
419         st->l3.l3m.fsm = &l3fsm;
420         st->l3.l3m.state = ST_L3_LC_REL;
421         st->l3.l3m.debug = 1;
422         st->l3.l3m.userdata = st;
423         st->l3.l3m.userint = 0;
424         st->l3.l3m.printdebug = l3m_debug;
425         strcpy(st->l3.debug_id, "L3BC ");
426         st->lli.l4l3 = isdnl3_trans;
427 }
428
429 #define DREL_TIMER_VALUE 40000
430
431 static void
432 lc_activate(struct FsmInst *fi, int event, void *arg)
433 {
434         struct PStack *st = fi->userdata;
435
436         FsmChangeState(fi, ST_L3_LC_ESTAB_WAIT);
437         st->l3.l3l2(st, DL_ESTABLISH | REQUEST, NULL);
438 }
439
440 static void
441 lc_connect(struct FsmInst *fi, int event, void *arg)
442 {
443         struct PStack *st = fi->userdata;
444         struct sk_buff *skb = arg;
445         int dequeued = 0;
446
447         FsmChangeState(fi, ST_L3_LC_ESTAB);
448         while ((skb = skb_dequeue(&st->l3.squeue))) {
449                 st->l3.l3l2(st, DL_DATA | REQUEST, skb);
450                 dequeued++;
451         }
452         if ((!st->l3.proc) &&  dequeued) {
453                 if (st->l3.debug)
454                         l3_debug(st, "lc_connect: release link");
455                 FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
456         } else
457                 l3ml3p(st, DL_ESTABLISH | INDICATION);
458 }
459
460 static void
461 lc_connected(struct FsmInst *fi, int event, void *arg)
462 {
463         struct PStack *st = fi->userdata;
464         struct sk_buff *skb = arg;
465         int dequeued = 0;
466
467         FsmDelTimer(&st->l3.l3m_timer, 51);
468         FsmChangeState(fi, ST_L3_LC_ESTAB);
469         while ((skb = skb_dequeue(&st->l3.squeue))) {
470                 st->l3.l3l2(st, DL_DATA | REQUEST, skb);
471                 dequeued++;
472         }
473         if ((!st->l3.proc) &&  dequeued) {
474                 if (st->l3.debug)
475                         l3_debug(st, "lc_connected: release link");
476                 FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
477         } else
478                 l3ml3p(st, DL_ESTABLISH | CONFIRM);
479 }
480
481 static void
482 lc_start_delay(struct FsmInst *fi, int event, void *arg)
483 {
484        struct PStack *st = fi->userdata;
485
486        FsmChangeState(fi, ST_L3_LC_REL_DELAY);
487        FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 50);
488 }
489
490 static void
491 lc_start_delay_check(struct FsmInst *fi, int event, void *arg)
492 /* 20/09/00 - GE timer not user for NI-1 as layer 2 should stay up */
493 {
494        struct PStack *st = fi->userdata;
495
496        FsmChangeState(fi, ST_L3_LC_REL_DELAY);
497        /* 19/09/00 - GE timer not user for NI-1 */
498        if (st->protocol != ISDN_PTYPE_NI1) 
499                 FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 50);
500 }
501
502 static void
503 lc_release_req(struct FsmInst *fi, int event, void *arg)
504 {
505         struct PStack *st = fi->userdata;
506
507         if (test_bit(FLG_L2BLOCK, &st->l2.flag)) {
508                 if (st->l3.debug)
509                         l3_debug(st, "lc_release_req: l2 blocked");
510                 /* restart release timer */
511                 FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 51);
512         } else {
513                 FsmChangeState(fi, ST_L3_LC_REL_WAIT);
514                 st->l3.l3l2(st, DL_RELEASE | REQUEST, NULL);
515         }
516 }
517
518 static void
519 lc_release_ind(struct FsmInst *fi, int event, void *arg)
520 {
521         struct PStack *st = fi->userdata;
522
523         FsmDelTimer(&st->l3.l3m_timer, 52);
524         FsmChangeState(fi, ST_L3_LC_REL);
525         skb_queue_purge(&st->l3.squeue);
526         l3ml3p(st, DL_RELEASE | INDICATION);
527 }
528
529 static void
530 lc_release_cnf(struct FsmInst *fi, int event, void *arg)
531 {
532         struct PStack *st = fi->userdata;
533
534         FsmChangeState(fi, ST_L3_LC_REL);
535         skb_queue_purge(&st->l3.squeue);
536         l3ml3p(st, DL_RELEASE | CONFIRM);
537 }
538
539
540 /* *INDENT-OFF* */
541 static struct FsmNode L3FnList[] __initdata =
542 {
543         {ST_L3_LC_REL,          EV_ESTABLISH_REQ,       lc_activate},
544         {ST_L3_LC_REL,          EV_ESTABLISH_IND,       lc_connect},
545         {ST_L3_LC_REL,          EV_ESTABLISH_CNF,       lc_connect},
546         {ST_L3_LC_ESTAB_WAIT,   EV_ESTABLISH_CNF,       lc_connected},
547         {ST_L3_LC_ESTAB_WAIT,   EV_RELEASE_REQ,         lc_start_delay},
548         {ST_L3_LC_ESTAB_WAIT,   EV_RELEASE_IND,         lc_release_ind},
549         {ST_L3_LC_ESTAB,        EV_RELEASE_IND,         lc_release_ind},
550         {ST_L3_LC_ESTAB,        EV_RELEASE_REQ,         lc_start_delay_check},
551         {ST_L3_LC_REL_DELAY,    EV_RELEASE_IND,         lc_release_ind},
552         {ST_L3_LC_REL_DELAY,    EV_ESTABLISH_REQ,       lc_connected},
553         {ST_L3_LC_REL_DELAY,    EV_TIMEOUT,             lc_release_req},
554         {ST_L3_LC_REL_WAIT,     EV_RELEASE_CNF,         lc_release_cnf},
555         {ST_L3_LC_REL_WAIT,     EV_ESTABLISH_REQ,       lc_activate},
556 };
557 /* *INDENT-ON* */
558
559 #define L3_FN_COUNT (sizeof(L3FnList)/sizeof(struct FsmNode))
560
561 void
562 l3_msg(struct PStack *st, int pr, void *arg)
563 {
564         switch (pr) {
565                 case (DL_DATA | REQUEST):
566                         if (st->l3.l3m.state == ST_L3_LC_ESTAB) {
567                                 st->l3.l3l2(st, pr, arg);
568                         } else {
569                                 struct sk_buff *skb = arg;
570
571                                 skb_queue_tail(&st->l3.squeue, skb);
572                                 FsmEvent(&st->l3.l3m, EV_ESTABLISH_REQ, NULL); 
573                         }
574                         break;
575                 case (DL_ESTABLISH | REQUEST):
576                         FsmEvent(&st->l3.l3m, EV_ESTABLISH_REQ, NULL);
577                         break;
578                 case (DL_ESTABLISH | CONFIRM):
579                         FsmEvent(&st->l3.l3m, EV_ESTABLISH_CNF, NULL);
580                         break;
581                 case (DL_ESTABLISH | INDICATION):
582                         FsmEvent(&st->l3.l3m, EV_ESTABLISH_IND, NULL);
583                         break;
584                 case (DL_RELEASE | INDICATION):
585                         FsmEvent(&st->l3.l3m, EV_RELEASE_IND, NULL);
586                         break;
587                 case (DL_RELEASE | CONFIRM):
588                         FsmEvent(&st->l3.l3m, EV_RELEASE_CNF, NULL);
589                         break;
590                 case (DL_RELEASE | REQUEST):
591                         FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
592                         break;
593         }
594 }
595
596 int __init
597 Isdnl3New(void)
598 {
599         l3fsm.state_count = L3_STATE_COUNT;
600         l3fsm.event_count = L3_EVENT_COUNT;
601         l3fsm.strEvent = strL3Event;
602         l3fsm.strState = strL3State;
603         return FsmNew(&l3fsm, L3FnList, L3_FN_COUNT);
604 }
605
606 void
607 Isdnl3Free(void)
608 {
609         FsmFree(&l3fsm);
610 }