irda: Fix error propagation in ircomm_lmp_connect_response()
[linux-3.10.git] / net / irda / ircomm / ircomm_lmp.c
1 /*********************************************************************
2  *
3  * Filename:      ircomm_lmp.c
4  * Version:       1.0
5  * Description:   Interface between IrCOMM and IrLMP
6  * Status:        Stable
7  * Author:        Dag Brattli <dagb@cs.uit.no>
8  * Created at:    Sun Jun  6 20:48:27 1999
9  * Modified at:   Sun Dec 12 13:44:17 1999
10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
11  * Sources:       Previous IrLPT work by Thomas Davis
12  *
13  *     Copyright (c) 1999 Dag Brattli, 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  *     This program is distributed in the hope that it will be useful,
22  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
23  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24  *     GNU General Public License for more details.
25  *
26  *     You should have received a copy of the GNU General Public License
27  *     along with this program; if not, write to the Free Software
28  *     Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29  *     MA 02111-1307 USA
30  *
31  ********************************************************************/
32
33 #include <linux/init.h>
34 #include <linux/gfp.h>
35
36 #include <net/irda/irda.h>
37 #include <net/irda/irlmp.h>
38 #include <net/irda/iriap.h>
39 #include <net/irda/irda_device.h>       /* struct irda_skb_cb */
40
41 #include <net/irda/ircomm_event.h>
42 #include <net/irda/ircomm_lmp.h>
43
44
45 /*
46  * Function ircomm_lmp_connect_request (self, userdata)
47  *
48  *
49  *
50  */
51 static int ircomm_lmp_connect_request(struct ircomm_cb *self,
52                                       struct sk_buff *userdata,
53                                       struct ircomm_info *info)
54 {
55         int ret = 0;
56
57         IRDA_DEBUG(0, "%s()\n", __func__ );
58
59         /* Don't forget to refcount it - should be NULL anyway */
60         if(userdata)
61                 skb_get(userdata);
62
63         ret = irlmp_connect_request(self->lsap, info->dlsap_sel,
64                                     info->saddr, info->daddr, NULL, userdata);
65         return ret;
66 }
67
68 /*
69  * Function ircomm_lmp_connect_response (self, skb)
70  *
71  *
72  *
73  */
74 static int ircomm_lmp_connect_response(struct ircomm_cb *self,
75                                        struct sk_buff *userdata)
76 {
77         struct sk_buff *tx_skb;
78
79         IRDA_DEBUG(0, "%s()\n", __func__ );
80
81         /* Any userdata supplied? */
82         if (userdata == NULL) {
83                 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
84                 if (!tx_skb)
85                         return -ENOMEM;
86
87                 /* Reserve space for MUX and LAP header */
88                 skb_reserve(tx_skb, LMP_MAX_HEADER);
89         } else {
90                 /*
91                  *  Check that the client has reserved enough space for
92                  *  headers
93                  */
94                 IRDA_ASSERT(skb_headroom(userdata) >= LMP_MAX_HEADER,
95                             return -1;);
96
97                 /* Don't forget to refcount it - should be NULL anyway */
98                 skb_get(userdata);
99                 tx_skb = userdata;
100         }
101
102         return irlmp_connect_response(self->lsap, tx_skb);
103 }
104
105 static int ircomm_lmp_disconnect_request(struct ircomm_cb *self,
106                                          struct sk_buff *userdata,
107                                          struct ircomm_info *info)
108 {
109         struct sk_buff *tx_skb;
110         int ret;
111
112         IRDA_DEBUG(0, "%s()\n", __func__ );
113
114         if (!userdata) {
115                 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
116                 if (!tx_skb)
117                         return -ENOMEM;
118
119                 /*  Reserve space for MUX and LAP header */
120                 skb_reserve(tx_skb, LMP_MAX_HEADER);
121                 userdata = tx_skb;
122         } else {
123                 /* Don't forget to refcount it - should be NULL anyway */
124                 skb_get(userdata);
125         }
126
127         ret = irlmp_disconnect_request(self->lsap, userdata);
128
129         return ret;
130 }
131
132 /*
133  * Function ircomm_lmp_flow_control (skb)
134  *
135  *    This function is called when a data frame we have sent to IrLAP has
136  *    been deallocated. We do this to make sure we don't flood IrLAP with
137  *    frames, since we are not using the IrTTP flow control mechanism
138  */
139 static void ircomm_lmp_flow_control(struct sk_buff *skb)
140 {
141         struct irda_skb_cb *cb;
142         struct ircomm_cb *self;
143         int line;
144
145         IRDA_ASSERT(skb != NULL, return;);
146
147         cb = (struct irda_skb_cb *) skb->cb;
148
149         IRDA_DEBUG(2, "%s()\n", __func__ );
150
151         line = cb->line;
152
153         self = (struct ircomm_cb *) hashbin_lock_find(ircomm, line, NULL);
154         if (!self) {
155                 IRDA_DEBUG(2, "%s(), didn't find myself\n", __func__ );
156                 return;
157         }
158
159         IRDA_ASSERT(self != NULL, return;);
160         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
161
162         self->pkt_count--;
163
164         if ((self->pkt_count < 2) && (self->flow_status == FLOW_STOP)) {
165                 IRDA_DEBUG(2, "%s(), asking TTY to start again!\n", __func__ );
166                 self->flow_status = FLOW_START;
167                 if (self->notify.flow_indication)
168                         self->notify.flow_indication(self->notify.instance,
169                                                      self, FLOW_START);
170         }
171 }
172
173 /*
174  * Function ircomm_lmp_data_request (self, userdata)
175  *
176  *    Send data frame to peer device
177  *
178  */
179 static int ircomm_lmp_data_request(struct ircomm_cb *self,
180                                    struct sk_buff *skb,
181                                    int not_used)
182 {
183         struct irda_skb_cb *cb;
184         int ret;
185
186         IRDA_ASSERT(skb != NULL, return -1;);
187
188         cb = (struct irda_skb_cb *) skb->cb;
189
190         cb->line = self->line;
191
192         IRDA_DEBUG(4, "%s(), sending frame\n", __func__ );
193
194         /* Don't forget to refcount it - see ircomm_tty_do_softint() */
195         skb_get(skb);
196
197         skb_orphan(skb);
198         skb->destructor = ircomm_lmp_flow_control;
199
200         if ((self->pkt_count++ > 7) && (self->flow_status == FLOW_START)) {
201                 IRDA_DEBUG(2, "%s(), asking TTY to slow down!\n", __func__ );
202                 self->flow_status = FLOW_STOP;
203                 if (self->notify.flow_indication)
204                         self->notify.flow_indication(self->notify.instance,
205                                                      self, FLOW_STOP);
206         }
207         ret = irlmp_data_request(self->lsap, skb);
208         if (ret) {
209                 IRDA_ERROR("%s(), failed\n", __func__);
210                 /* irlmp_data_request already free the packet */
211         }
212
213         return ret;
214 }
215
216 /*
217  * Function ircomm_lmp_data_indication (instance, sap, skb)
218  *
219  *    Incoming data which we must deliver to the state machine, to check
220  *    we are still connected.
221  */
222 static int ircomm_lmp_data_indication(void *instance, void *sap,
223                                       struct sk_buff *skb)
224 {
225         struct ircomm_cb *self = (struct ircomm_cb *) instance;
226
227         IRDA_DEBUG(4, "%s()\n", __func__ );
228
229         IRDA_ASSERT(self != NULL, return -1;);
230         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return -1;);
231         IRDA_ASSERT(skb != NULL, return -1;);
232
233         ircomm_do_event(self, IRCOMM_LMP_DATA_INDICATION, skb, NULL);
234
235         /* Drop reference count - see ircomm_tty_data_indication(). */
236         dev_kfree_skb(skb);
237
238         return 0;
239 }
240
241 /*
242  * Function ircomm_lmp_connect_confirm (instance, sap, qos, max_sdu_size,
243  *                                       max_header_size, skb)
244  *
245  *    Connection has been confirmed by peer device
246  *
247  */
248 static void ircomm_lmp_connect_confirm(void *instance, void *sap,
249                                        struct qos_info *qos,
250                                        __u32 max_seg_size,
251                                        __u8 max_header_size,
252                                        struct sk_buff *skb)
253 {
254         struct ircomm_cb *self = (struct ircomm_cb *) instance;
255         struct ircomm_info info;
256
257         IRDA_DEBUG(0, "%s()\n", __func__ );
258
259         IRDA_ASSERT(self != NULL, return;);
260         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
261         IRDA_ASSERT(skb != NULL, return;);
262         IRDA_ASSERT(qos != NULL, return;);
263
264         info.max_data_size = max_seg_size;
265         info.max_header_size = max_header_size;
266         info.qos = qos;
267
268         ircomm_do_event(self, IRCOMM_LMP_CONNECT_CONFIRM, skb, &info);
269
270         /* Drop reference count - see ircomm_tty_connect_confirm(). */
271         dev_kfree_skb(skb);
272 }
273
274 /*
275  * Function ircomm_lmp_connect_indication (instance, sap, qos, max_sdu_size,
276  *                                         max_header_size, skb)
277  *
278  *    Peer device wants to make a connection with us
279  *
280  */
281 static void ircomm_lmp_connect_indication(void *instance, void *sap,
282                                           struct qos_info *qos,
283                                           __u32 max_seg_size,
284                                           __u8 max_header_size,
285                                           struct sk_buff *skb)
286 {
287         struct ircomm_cb *self = (struct ircomm_cb *)instance;
288         struct ircomm_info info;
289
290         IRDA_DEBUG(0, "%s()\n", __func__ );
291
292         IRDA_ASSERT(self != NULL, return;);
293         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
294         IRDA_ASSERT(skb != NULL, return;);
295         IRDA_ASSERT(qos != NULL, return;);
296
297         info.max_data_size = max_seg_size;
298         info.max_header_size = max_header_size;
299         info.qos = qos;
300
301         ircomm_do_event(self, IRCOMM_LMP_CONNECT_INDICATION, skb, &info);
302
303         /* Drop reference count - see ircomm_tty_connect_indication(). */
304         dev_kfree_skb(skb);
305 }
306
307 /*
308  * Function ircomm_lmp_disconnect_indication (instance, sap, reason, skb)
309  *
310  *    Peer device has closed the connection, or the link went down for some
311  *    other reason
312  */
313 static void ircomm_lmp_disconnect_indication(void *instance, void *sap,
314                                              LM_REASON reason,
315                                              struct sk_buff *skb)
316 {
317         struct ircomm_cb *self = (struct ircomm_cb *) instance;
318         struct ircomm_info info;
319
320         IRDA_DEBUG(0, "%s()\n", __func__ );
321
322         IRDA_ASSERT(self != NULL, return;);
323         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
324
325         info.reason = reason;
326
327         ircomm_do_event(self, IRCOMM_LMP_DISCONNECT_INDICATION, skb, &info);
328
329         /* Drop reference count - see ircomm_tty_disconnect_indication(). */
330         if(skb)
331                 dev_kfree_skb(skb);
332 }
333 /*
334  * Function ircomm_open_lsap (self)
335  *
336  *    Open LSAP. This function will only be used when using "raw" services
337  *
338  */
339 int ircomm_open_lsap(struct ircomm_cb *self)
340 {
341         notify_t notify;
342
343         IRDA_DEBUG(0, "%s()\n", __func__ );
344
345         /* Register callbacks */
346         irda_notify_init(&notify);
347         notify.data_indication       = ircomm_lmp_data_indication;
348         notify.connect_confirm       = ircomm_lmp_connect_confirm;
349         notify.connect_indication    = ircomm_lmp_connect_indication;
350         notify.disconnect_indication = ircomm_lmp_disconnect_indication;
351         notify.instance = self;
352         strlcpy(notify.name, "IrCOMM", sizeof(notify.name));
353
354         self->lsap = irlmp_open_lsap(LSAP_ANY, &notify, 0);
355         if (!self->lsap) {
356                 IRDA_DEBUG(0,"%sfailed to allocate tsap\n", __func__ );
357                 return -1;
358         }
359         self->slsap_sel = self->lsap->slsap_sel;
360
361         /*
362          *  Initialize the call-table for issuing commands
363          */
364         self->issue.data_request       = ircomm_lmp_data_request;
365         self->issue.connect_request    = ircomm_lmp_connect_request;
366         self->issue.connect_response   = ircomm_lmp_connect_response;
367         self->issue.disconnect_request = ircomm_lmp_disconnect_request;
368
369         return 0;
370 }