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         int ret;
  79
  80         IRDA_DEBUG(0, "%s()\n", __func__ );
  81
  82         /* Any userdata supplied? */
  83         if (userdata == NULL) {
  84                 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
  85                 if (!tx_skb)
  86                         return -ENOMEM;
  87
  88                 /* Reserve space for MUX and LAP header */
  89                 skb_reserve(tx_skb, LMP_MAX_HEADER);
  90         } else {
  91                 /*
  92                  *  Check that the client has reserved enough space for
  93                  *  headers
  94                  */
  95                 IRDA_ASSERT(skb_headroom(userdata) >= LMP_MAX_HEADER,
  96                             return -1;);
  97
  98                 /* Don't forget to refcount it - should be NULL anyway */
  99                 skb_get(userdata);
 100                 tx_skb = userdata;
 101         }
 102
 103         ret = irlmp_connect_response(self->lsap, tx_skb);
 104
 105         return 0;
 106 }
 107
 108 static int ircomm_lmp_disconnect_request(struct ircomm_cb *self,
 109                                          struct sk_buff *userdata,
 110                                          struct ircomm_info *info)
 111 {
 112         struct sk_buff *tx_skb;
 113         int ret;
 114
 115         IRDA_DEBUG(0, "%s()\n", __func__ );
 116
 117         if (!userdata) {
 118                 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
 119                 if (!tx_skb)
 120                         return -ENOMEM;
 121
 122                 /*  Reserve space for MUX and LAP header */
 123                 skb_reserve(tx_skb, LMP_MAX_HEADER);
 124                 userdata = tx_skb;
 125         } else {
 126                 /* Don't forget to refcount it - should be NULL anyway */
 127                 skb_get(userdata);
 128         }
 129
 130         ret = irlmp_disconnect_request(self->lsap, userdata);
 131
 132         return ret;
 133 }
 134
 135 /*
 136  * Function ircomm_lmp_flow_control (skb)
 137  *
 138  *    This function is called when a data frame we have sent to IrLAP has
 139  *    been deallocated. We do this to make sure we don't flood IrLAP with
 140  *    frames, since we are not using the IrTTP flow control mechanism
 141  */
 142 static void ircomm_lmp_flow_control(struct sk_buff *skb)
 143 {
 144         struct irda_skb_cb *cb;
 145         struct ircomm_cb *self;
 146         int line;
 147
 148         IRDA_ASSERT(skb != NULL, return;);
 149
 150         cb = (struct irda_skb_cb *) skb->cb;
 151
 152         IRDA_DEBUG(2, "%s()\n", __func__ );
 153
 154         line = cb->line;
 155
 156         self = (struct ircomm_cb *) hashbin_lock_find(ircomm, line, NULL);
 157         if (!self) {
 158                 IRDA_DEBUG(2, "%s(), didn't find myself\n", __func__ );
 159                 return;
 160         }
 161
 162         IRDA_ASSERT(self != NULL, return;);
 163         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 164
 165         self->pkt_count--;
 166
 167         if ((self->pkt_count < 2) && (self->flow_status == FLOW_STOP)) {
 168                 IRDA_DEBUG(2, "%s(), asking TTY to start again!\n", __func__ );
 169                 self->flow_status = FLOW_START;
 170                 if (self->notify.flow_indication)
 171                         self->notify.flow_indication(self->notify.instance,
 172                                                      self, FLOW_START);
 173         }
 174 }
 175
 176 /*
 177  * Function ircomm_lmp_data_request (self, userdata)
 178  *
 179  *    Send data frame to peer device
 180  *
 181  */
 182 static int ircomm_lmp_data_request(struct ircomm_cb *self,
 183                                    struct sk_buff *skb,
 184                                    int not_used)
 185 {
 186         struct irda_skb_cb *cb;
 187         int ret;
 188
 189         IRDA_ASSERT(skb != NULL, return -1;);
 190
 191         cb = (struct irda_skb_cb *) skb->cb;
 192
 193         cb->line = self->line;
 194
 195         IRDA_DEBUG(4, "%s(), sending frame\n", __func__ );
 196
 197         /* Don't forget to refcount it - see ircomm_tty_do_softint() */
 198         skb_get(skb);
 199
 200         skb_orphan(skb);
 201         skb->destructor = ircomm_lmp_flow_control;
 202
 203         if ((self->pkt_count++ > 7) && (self->flow_status == FLOW_START)) {
 204                 IRDA_DEBUG(2, "%s(), asking TTY to slow down!\n", __func__ );
 205                 self->flow_status = FLOW_STOP;
 206                 if (self->notify.flow_indication)
 207                         self->notify.flow_indication(self->notify.instance,
 208                                                      self, FLOW_STOP);
 209         }
 210         ret = irlmp_data_request(self->lsap, skb);
 211         if (ret) {
 212                 IRDA_ERROR("%s(), failed\n", __func__);
 213                 /* irlmp_data_request already free the packet */
 214         }
 215
 216         return ret;
 217 }
 218
 219 /*
 220  * Function ircomm_lmp_data_indication (instance, sap, skb)
 221  *
 222  *    Incoming data which we must deliver to the state machine, to check
 223  *    we are still connected.
 224  */
 225 static int ircomm_lmp_data_indication(void *instance, void *sap,
 226                                       struct sk_buff *skb)
 227 {
 228         struct ircomm_cb *self = (struct ircomm_cb *) instance;
 229
 230         IRDA_DEBUG(4, "%s()\n", __func__ );
 231
 232         IRDA_ASSERT(self != NULL, return -1;);
 233         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return -1;);
 234         IRDA_ASSERT(skb != NULL, return -1;);
 235
 236         ircomm_do_event(self, IRCOMM_LMP_DATA_INDICATION, skb, NULL);
 237
 238         /* Drop reference count - see ircomm_tty_data_indication(). */
 239         dev_kfree_skb(skb);
 240
 241         return 0;
 242 }
 243
 244 /*
 245  * Function ircomm_lmp_connect_confirm (instance, sap, qos, max_sdu_size,
 246  *                                       max_header_size, skb)
 247  *
 248  *    Connection has been confirmed by peer device
 249  *
 250  */
 251 static void ircomm_lmp_connect_confirm(void *instance, void *sap,
 252                                        struct qos_info *qos,
 253                                        __u32 max_seg_size,
 254                                        __u8 max_header_size,
 255                                        struct sk_buff *skb)
 256 {
 257         struct ircomm_cb *self = (struct ircomm_cb *) instance;
 258         struct ircomm_info info;
 259
 260         IRDA_DEBUG(0, "%s()\n", __func__ );
 261
 262         IRDA_ASSERT(self != NULL, return;);
 263         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 264         IRDA_ASSERT(skb != NULL, return;);
 265         IRDA_ASSERT(qos != NULL, return;);
 266
 267         info.max_data_size = max_seg_size;
 268         info.max_header_size = max_header_size;
 269         info.qos = qos;
 270
 271         ircomm_do_event(self, IRCOMM_LMP_CONNECT_CONFIRM, skb, &info);
 272
 273         /* Drop reference count - see ircomm_tty_connect_confirm(). */
 274         dev_kfree_skb(skb);
 275 }
 276
 277 /*
 278  * Function ircomm_lmp_connect_indication (instance, sap, qos, max_sdu_size,
 279  *                                         max_header_size, skb)
 280  *
 281  *    Peer device wants to make a connection with us
 282  *
 283  */
 284 static void ircomm_lmp_connect_indication(void *instance, void *sap,
 285                                           struct qos_info *qos,
 286                                           __u32 max_seg_size,
 287                                           __u8 max_header_size,
 288                                           struct sk_buff *skb)
 289 {
 290         struct ircomm_cb *self = (struct ircomm_cb *)instance;
 291         struct ircomm_info info;
 292
 293         IRDA_DEBUG(0, "%s()\n", __func__ );
 294
 295         IRDA_ASSERT(self != NULL, return;);
 296         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 297         IRDA_ASSERT(skb != NULL, return;);
 298         IRDA_ASSERT(qos != NULL, return;);
 299
 300         info.max_data_size = max_seg_size;
 301         info.max_header_size = max_header_size;
 302         info.qos = qos;
 303
 304         ircomm_do_event(self, IRCOMM_LMP_CONNECT_INDICATION, skb, &info);
 305
 306         /* Drop reference count - see ircomm_tty_connect_indication(). */
 307         dev_kfree_skb(skb);
 308 }
 309
 310 /*
 311  * Function ircomm_lmp_disconnect_indication (instance, sap, reason, skb)
 312  *
 313  *    Peer device has closed the connection, or the link went down for some
 314  *    other reason
 315  */
 316 static void ircomm_lmp_disconnect_indication(void *instance, void *sap,
 317                                              LM_REASON reason,
 318                                              struct sk_buff *skb)
 319 {
 320         struct ircomm_cb *self = (struct ircomm_cb *) instance;
 321         struct ircomm_info info;
 322
 323         IRDA_DEBUG(0, "%s()\n", __func__ );
 324
 325         IRDA_ASSERT(self != NULL, return;);
 326         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 327
 328         info.reason = reason;
 329
 330         ircomm_do_event(self, IRCOMM_LMP_DISCONNECT_INDICATION, skb, &info);
 331
 332         /* Drop reference count - see ircomm_tty_disconnect_indication(). */
 333         if(skb)
 334                 dev_kfree_skb(skb);
 335 }
 336 /*
 337  * Function ircomm_open_lsap (self)
 338  *
 339  *    Open LSAP. This function will only be used when using "raw" services
 340  *
 341  */
 342 int ircomm_open_lsap(struct ircomm_cb *self)
 343 {
 344         notify_t notify;
 345
 346         IRDA_DEBUG(0, "%s()\n", __func__ );
 347
 348         /* Register callbacks */
 349         irda_notify_init(&notify);
 350         notify.data_indication       = ircomm_lmp_data_indication;
 351         notify.connect_confirm       = ircomm_lmp_connect_confirm;
 352         notify.connect_indication    = ircomm_lmp_connect_indication;
 353         notify.disconnect_indication = ircomm_lmp_disconnect_indication;
 354         notify.instance = self;
 355         strlcpy(notify.name, "IrCOMM", sizeof(notify.name));
 356
 357         self->lsap = irlmp_open_lsap(LSAP_ANY, &notify, 0);
 358         if (!self->lsap) {
 359                 IRDA_DEBUG(0,"%sfailed to allocate tsap\n", __func__ );
 360                 return -1;
 361         }
 362         self->slsap_sel = self->lsap->slsap_sel;
 363
 364         /*
 365          *  Initialize the call-table for issuing commands
 366          */
 367         self->issue.data_request       = ircomm_lmp_data_request;
 368         self->issue.connect_request    = ircomm_lmp_connect_request;
 369         self->issue.connect_response   = ircomm_lmp_connect_response;
 370         self->issue.disconnect_request = ircomm_lmp_disconnect_request;
 371
 372         return 0;
 373 }