[JFFS2] Forbid to free inode_cache objects if its nlink isn't zero.
[linux-2.6] / net / irda / iriap_event.c
1 /*********************************************************************
2  *
3  * Filename:      iriap_event.c
4  * Version:       0.1
5  * Description:   IAP Finite State Machine
6  * Status:        Experimental.
7  * Author:        Dag Brattli <dagb@cs.uit.no>
8  * Created at:    Thu Aug 21 00:02:07 1997
9  * Modified at:   Wed Mar  1 11:28:34 2000
10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
11  *
12  *     Copyright (c) 1997, 1999-2000 Dag Brattli <dagb@cs.uit.no>,
13  *     All Rights Reserved.
14  *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
15  *
16  *     This program is free software; you can redistribute it and/or
17  *     modify it under the terms of the GNU General Public License as
18  *     published by the Free Software Foundation; either version 2 of
19  *     the License, or (at your option) any later version.
20  *
21  *     Neither Dag Brattli nor University of Tromsø admit liability nor
22  *     provide warranty for any of this software. This material is
23  *     provided "AS-IS" and at no charge.
24  *
25  ********************************************************************/
26
27 #include <net/irda/irda.h>
28 #include <net/irda/irlmp.h>
29 #include <net/irda/iriap.h>
30 #include <net/irda/iriap_event.h>
31
32 static void state_s_disconnect   (struct iriap_cb *self, IRIAP_EVENT event,
33                                   struct sk_buff *skb);
34 static void state_s_connecting   (struct iriap_cb *self, IRIAP_EVENT event,
35                                   struct sk_buff *skb);
36 static void state_s_call         (struct iriap_cb *self, IRIAP_EVENT event,
37                                   struct sk_buff *skb);
38
39 static void state_s_make_call    (struct iriap_cb *self, IRIAP_EVENT event,
40                                   struct sk_buff *skb);
41 static void state_s_calling      (struct iriap_cb *self, IRIAP_EVENT event,
42                                   struct sk_buff *skb);
43 static void state_s_outstanding  (struct iriap_cb *self, IRIAP_EVENT event,
44                                   struct sk_buff *skb);
45 static void state_s_replying     (struct iriap_cb *self, IRIAP_EVENT event,
46                                   struct sk_buff *skb);
47 static void state_s_wait_for_call(struct iriap_cb *self, IRIAP_EVENT event,
48                                   struct sk_buff *skb);
49 static void state_s_wait_active  (struct iriap_cb *self, IRIAP_EVENT event,
50                                   struct sk_buff *skb);
51
52 static void state_r_disconnect   (struct iriap_cb *self, IRIAP_EVENT event,
53                                   struct sk_buff *skb);
54 static void state_r_call         (struct iriap_cb *self, IRIAP_EVENT event,
55                                   struct sk_buff *skb);
56 static void state_r_waiting      (struct iriap_cb *self, IRIAP_EVENT event,
57                                   struct sk_buff *skb);
58 static void state_r_wait_active  (struct iriap_cb *self, IRIAP_EVENT event,
59                                   struct sk_buff *skb);
60 static void state_r_receiving    (struct iriap_cb *self, IRIAP_EVENT event,
61                                   struct sk_buff *skb);
62 static void state_r_execute      (struct iriap_cb *self, IRIAP_EVENT event,
63                                   struct sk_buff *skb);
64 static void state_r_returning    (struct iriap_cb *self, IRIAP_EVENT event,
65                                   struct sk_buff *skb);
66
67 static void (*iriap_state[])(struct iriap_cb *self, IRIAP_EVENT event,
68                              struct sk_buff *skb) = {
69         /* Client FSM */
70         state_s_disconnect,
71         state_s_connecting,
72         state_s_call,
73
74         /* S-Call FSM */
75         state_s_make_call,
76         state_s_calling,
77         state_s_outstanding,
78         state_s_replying,
79         state_s_wait_for_call,
80         state_s_wait_active,
81
82         /* Server FSM */
83         state_r_disconnect,
84         state_r_call,
85
86         /* R-Connect FSM */
87         state_r_waiting,
88         state_r_wait_active,
89         state_r_receiving,
90         state_r_execute,
91         state_r_returning,
92 };
93
94 void iriap_next_client_state(struct iriap_cb *self, IRIAP_STATE state)
95 {
96         IRDA_ASSERT(self != NULL, return;);
97         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
98
99         self->client_state = state;
100 }
101
102 void iriap_next_call_state(struct iriap_cb *self, IRIAP_STATE state)
103 {
104         IRDA_ASSERT(self != NULL, return;);
105         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
106
107         self->call_state = state;
108 }
109
110 void iriap_next_server_state(struct iriap_cb *self, IRIAP_STATE state)
111 {
112         IRDA_ASSERT(self != NULL, return;);
113         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
114
115         self->server_state = state;
116 }
117
118 void iriap_next_r_connect_state(struct iriap_cb *self, IRIAP_STATE state)
119 {
120         IRDA_ASSERT(self != NULL, return;);
121         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
122
123         self->r_connect_state = state;
124 }
125
126 void iriap_do_client_event(struct iriap_cb *self, IRIAP_EVENT event,
127                            struct sk_buff *skb)
128 {
129         IRDA_ASSERT(self != NULL, return;);
130         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
131
132         (*iriap_state[ self->client_state]) (self, event, skb);
133 }
134
135 void iriap_do_call_event(struct iriap_cb *self, IRIAP_EVENT event,
136                          struct sk_buff *skb)
137 {
138         IRDA_ASSERT(self != NULL, return;);
139         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
140
141         (*iriap_state[ self->call_state]) (self, event, skb);
142 }
143
144 void iriap_do_server_event(struct iriap_cb *self, IRIAP_EVENT event,
145                            struct sk_buff *skb)
146 {
147         IRDA_ASSERT(self != NULL, return;);
148         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
149
150         (*iriap_state[ self->server_state]) (self, event, skb);
151 }
152
153 void iriap_do_r_connect_event(struct iriap_cb *self, IRIAP_EVENT event,
154                               struct sk_buff *skb)
155 {
156         IRDA_ASSERT(self != NULL, return;);
157         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
158
159         (*iriap_state[ self->r_connect_state]) (self, event, skb);
160 }
161
162
163 /*
164  * Function state_s_disconnect (event, skb)
165  *
166  *    S-Disconnect, The device has no LSAP connection to a particular
167  *    remote device.
168  */
169 static void state_s_disconnect(struct iriap_cb *self, IRIAP_EVENT event,
170                                struct sk_buff *skb)
171 {
172         IRDA_ASSERT(self != NULL, return;);
173         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
174
175         switch (event) {
176         case IAP_CALL_REQUEST_GVBC:
177                 iriap_next_client_state(self, S_CONNECTING);
178                 IRDA_ASSERT(self->request_skb == NULL, return;);
179                 /* Don't forget to refcount it -
180                  * see iriap_getvaluebyclass_request(). */
181                 skb_get(skb);
182                 self->request_skb = skb;
183                 iriap_connect_request(self);
184                 break;
185         case IAP_LM_DISCONNECT_INDICATION:
186                 break;
187         default:
188                 IRDA_DEBUG(0, "%s(), Unknown event %d\n", __FUNCTION__, event);
189                 break;
190         }
191 }
192
193 /*
194  * Function state_s_connecting (self, event, skb)
195  *
196  *    S-Connecting
197  *
198  */
199 static void state_s_connecting(struct iriap_cb *self, IRIAP_EVENT event,
200                                struct sk_buff *skb)
201 {
202         IRDA_ASSERT(self != NULL, return;);
203         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
204
205         switch (event) {
206         case IAP_LM_CONNECT_CONFIRM:
207                 /*
208                  *  Jump to S-Call FSM
209                  */
210                 iriap_do_call_event(self, IAP_CALL_REQUEST, skb);
211                 /* iriap_call_request(self, 0,0,0); */
212                 iriap_next_client_state(self, S_CALL);
213                 break;
214         case IAP_LM_DISCONNECT_INDICATION:
215                 /* Abort calls */
216                 iriap_next_call_state(self, S_MAKE_CALL);
217                 iriap_next_client_state(self, S_DISCONNECT);
218                 break;
219         default:
220                 IRDA_DEBUG(0, "%s(), Unknown event %d\n", __FUNCTION__, event);
221                 break;
222         }
223 }
224
225 /*
226  * Function state_s_call (self, event, skb)
227  *
228  *    S-Call, The device can process calls to a specific remote
229  *    device. Whenever the LSAP connection is disconnected, this state
230  *    catches that event and clears up
231  */
232 static void state_s_call(struct iriap_cb *self, IRIAP_EVENT event,
233                          struct sk_buff *skb)
234 {
235         IRDA_ASSERT(self != NULL, return;);
236
237         switch (event) {
238         case IAP_LM_DISCONNECT_INDICATION:
239                 /* Abort calls */
240                 iriap_next_call_state(self, S_MAKE_CALL);
241                 iriap_next_client_state(self, S_DISCONNECT);
242                 break;
243         default:
244                 IRDA_DEBUG(0, "state_s_call: Unknown event %d\n", event);
245                 break;
246         }
247 }
248
249 /*
250  * Function state_s_make_call (event, skb)
251  *
252  *    S-Make-Call
253  *
254  */
255 static void state_s_make_call(struct iriap_cb *self, IRIAP_EVENT event,
256                               struct sk_buff *skb)
257 {
258         struct sk_buff *tx_skb;
259
260         IRDA_ASSERT(self != NULL, return;);
261
262         switch (event) {
263         case IAP_CALL_REQUEST:
264                 /* Already refcounted - see state_s_disconnect() */
265                 tx_skb = self->request_skb;
266                 self->request_skb = NULL;
267
268                 irlmp_data_request(self->lsap, tx_skb);
269                 iriap_next_call_state(self, S_OUTSTANDING);
270                 break;
271         default:
272                 IRDA_DEBUG(0, "%s(), Unknown event %d\n", __FUNCTION__, event);
273                 break;
274         }
275 }
276
277 /*
278  * Function state_s_calling (event, skb)
279  *
280  *    S-Calling
281  *
282  */
283 static void state_s_calling(struct iriap_cb *self, IRIAP_EVENT event,
284                             struct sk_buff *skb)
285 {
286         IRDA_DEBUG(0, "%s(), Not implemented\n", __FUNCTION__);
287 }
288
289 /*
290  * Function state_s_outstanding (event, skb)
291  *
292  *    S-Outstanding, The device is waiting for a response to a command
293  *
294  */
295 static void state_s_outstanding(struct iriap_cb *self, IRIAP_EVENT event,
296                                 struct sk_buff *skb)
297 {
298         IRDA_ASSERT(self != NULL, return;);
299
300         switch (event) {
301         case IAP_RECV_F_LST:
302                 /*iriap_send_ack(self);*/
303                 /*LM_Idle_request(idle); */
304
305                 iriap_next_call_state(self, S_WAIT_FOR_CALL);
306                 break;
307         default:
308                 IRDA_DEBUG(0, "%s(), Unknown event %d\n", __FUNCTION__, event);
309                 break;
310         }
311 }
312
313 /*
314  * Function state_s_replying (event, skb)
315  *
316  *    S-Replying, The device is collecting a multiple part response
317  */
318 static void state_s_replying(struct iriap_cb *self, IRIAP_EVENT event,
319                              struct sk_buff *skb)
320 {
321         IRDA_DEBUG(0, "%s(), Not implemented\n", __FUNCTION__);
322 }
323
324 /*
325  * Function state_s_wait_for_call (event, skb)
326  *
327  *    S-Wait-for-Call
328  *
329  */
330 static void state_s_wait_for_call(struct iriap_cb *self, IRIAP_EVENT event,
331                                   struct sk_buff *skb)
332 {
333         IRDA_DEBUG(0, "%s(), Not implemented\n", __FUNCTION__);
334 }
335
336
337 /*
338  * Function state_s_wait_active (event, skb)
339  *
340  *    S-Wait-Active
341  *
342  */
343 static void state_s_wait_active(struct iriap_cb *self, IRIAP_EVENT event,
344                                 struct sk_buff *skb)
345 {
346         IRDA_DEBUG(0, "%s(), Not implemented\n", __FUNCTION__);
347 }
348
349 /**************************************************************************
350  *
351  *  Server FSM
352  *
353  **************************************************************************/
354
355 /*
356  * Function state_r_disconnect (self, event, skb)
357  *
358  *    LM-IAS server is disconnected (not processing any requests!)
359  *
360  */
361 static void state_r_disconnect(struct iriap_cb *self, IRIAP_EVENT event,
362                                struct sk_buff *skb)
363 {
364         struct sk_buff *tx_skb;
365
366         switch (event) {
367         case IAP_LM_CONNECT_INDICATION:
368                 tx_skb = dev_alloc_skb(64);
369                 if (tx_skb == NULL) {
370                         IRDA_WARNING("%s: unable to malloc!\n", __FUNCTION__);
371                         return;
372                 }
373
374                 /* Reserve space for MUX_CONTROL and LAP header */
375                 skb_reserve(tx_skb, LMP_MAX_HEADER);
376
377                 irlmp_connect_response(self->lsap, tx_skb);
378                 /*LM_Idle_request(idle); */
379
380                 iriap_next_server_state(self, R_CALL);
381
382                 /*
383                  *  Jump to R-Connect FSM, we skip R-Waiting since we do not
384                  *  care about LM_Idle_request()!
385                  */
386                 iriap_next_r_connect_state(self, R_RECEIVING);
387                 break;
388         default:
389                 IRDA_DEBUG(0, "%s(), unknown event %d\n", __FUNCTION__, event);
390                 break;
391         }
392 }
393
394 /*
395  * Function state_r_call (self, event, skb)
396  */
397 static void state_r_call(struct iriap_cb *self, IRIAP_EVENT event,
398                          struct sk_buff *skb)
399 {
400         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
401
402         switch (event) {
403         case IAP_LM_DISCONNECT_INDICATION:
404                 /* Abort call */
405                 iriap_next_server_state(self, R_DISCONNECT);
406                 iriap_next_r_connect_state(self, R_WAITING);
407                 break;
408         default:
409                 IRDA_DEBUG(0, "%s(), unknown event!\n", __FUNCTION__);
410                 break;
411         }
412 }
413
414 /*
415  *  R-Connect FSM
416  */
417
418 /*
419  * Function state_r_waiting (self, event, skb)
420  */
421 static void state_r_waiting(struct iriap_cb *self, IRIAP_EVENT event,
422                             struct sk_buff *skb)
423 {
424         IRDA_DEBUG(0, "%s(), Not implemented\n", __FUNCTION__);
425 }
426
427 static void state_r_wait_active(struct iriap_cb *self, IRIAP_EVENT event,
428                                 struct sk_buff *skb)
429 {
430         IRDA_DEBUG(0, "%s(), Not implemented\n", __FUNCTION__);
431 }
432
433 /*
434  * Function state_r_receiving (self, event, skb)
435  *
436  *    We are receiving a command
437  *
438  */
439 static void state_r_receiving(struct iriap_cb *self, IRIAP_EVENT event,
440                               struct sk_buff *skb)
441 {
442         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
443
444         switch (event) {
445         case IAP_RECV_F_LST:
446                 iriap_next_r_connect_state(self, R_EXECUTE);
447
448                 iriap_call_indication(self, skb);
449                 break;
450         default:
451                 IRDA_DEBUG(0, "%s(), unknown event!\n", __FUNCTION__);
452                 break;
453         }
454 }
455
456 /*
457  * Function state_r_execute (self, event, skb)
458  *
459  *    The server is processing the request
460  *
461  */
462 static void state_r_execute(struct iriap_cb *self, IRIAP_EVENT event,
463                             struct sk_buff *skb)
464 {
465         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
466
467         IRDA_ASSERT(skb != NULL, return;);
468         IRDA_ASSERT(self != NULL, return;);
469         IRDA_ASSERT(self->magic == IAS_MAGIC, return;);
470
471         switch (event) {
472         case IAP_CALL_RESPONSE:
473                 /*
474                  *  Since we don't implement the Waiting state, we return
475                  *  to state Receiving instead, DB.
476                  */
477                 iriap_next_r_connect_state(self, R_RECEIVING);
478
479                 /* Don't forget to refcount it - see
480                  * iriap_getvaluebyclass_response(). */
481                 skb_get(skb);
482
483                 irlmp_data_request(self->lsap, skb);
484                 break;
485         default:
486                 IRDA_DEBUG(0, "%s(), unknown event!\n", __FUNCTION__);
487                 break;
488         }
489 }
490
491 static void state_r_returning(struct iriap_cb *self, IRIAP_EVENT event,
492                               struct sk_buff *skb)
493 {
494         IRDA_DEBUG(0, "%s(), event=%d\n", __FUNCTION__, event);
495
496         switch (event) {
497         case IAP_RECV_F_LST:
498                 break;
499         default:
500                 break;
501         }
502 }