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
  35 #include <net/irda/irda.h>
  36 #include <net/irda/irlmp.h>
  37 #include <net/irda/iriap.h>
  38 #include <net/irda/irda_device.h>       /* struct irda_skb_cb */
  39
  40 #include <net/irda/ircomm_event.h>
  41 #include <net/irda/ircomm_lmp.h>
  42
  43
  44 /*
  45  * Function ircomm_lmp_connect_request (self, userdata)
  46  *
  47  *
  48  *
  49  */
  50 static int ircomm_lmp_connect_request(struct ircomm_cb *self,
  51                                       struct sk_buff *userdata,
  52                                       struct ircomm_info *info)
  53 {
  54         int ret = 0;
  55
  56         IRDA_DEBUG(0, "%s()\n", __func__ );
  57
  58         /* Don't forget to refcount it - should be NULL anyway */
  59         if(userdata)
  60                 skb_get(userdata);
  61
  62         ret = irlmp_connect_request(self->lsap, info->dlsap_sel,
  63                                     info->saddr, info->daddr, NULL, userdata);
  64         return ret;
  65 }
  66
  67 /*
  68  * Function ircomm_lmp_connect_response (self, skb)
  69  *
  70  *
  71  *
  72  */
  73 static int ircomm_lmp_connect_response(struct ircomm_cb *self,
  74                                        struct sk_buff *userdata)
  75 {
  76         struct sk_buff *tx_skb;
  77         int ret;
  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         ret = irlmp_connect_response(self->lsap, tx_skb);
 103
 104         return 0;
 105 }
 106
 107 static int ircomm_lmp_disconnect_request(struct ircomm_cb *self,
 108                                          struct sk_buff *userdata,
 109                                          struct ircomm_info *info)
 110 {
 111         struct sk_buff *tx_skb;
 112         int ret;
 113
 114         IRDA_DEBUG(0, "%s()\n", __func__ );
 115
 116         if (!userdata) {
 117                 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
 118                 if (!tx_skb)
 119                         return -ENOMEM;
 120
 121                 /*  Reserve space for MUX and LAP header */
 122                 skb_reserve(tx_skb, LMP_MAX_HEADER);
 123                 userdata = tx_skb;
 124         } else {
 125                 /* Don't forget to refcount it - should be NULL anyway */
 126                 skb_get(userdata);
 127         }
 128
 129         ret = irlmp_disconnect_request(self->lsap, userdata);
 130
 131         return ret;
 132 }
 133
 134 /*
 135  * Function ircomm_lmp_flow_control (skb)
 136  *
 137  *    This function is called when a data frame we have sent to IrLAP has
 138  *    been deallocated. We do this to make sure we don't flood IrLAP with
 139  *    frames, since we are not using the IrTTP flow control mechanism
 140  */
 141 static void ircomm_lmp_flow_control(struct sk_buff *skb)
 142 {
 143         struct irda_skb_cb *cb;
 144         struct ircomm_cb *self;
 145         int line;
 146
 147         IRDA_ASSERT(skb != NULL, return;);
 148
 149         cb = (struct irda_skb_cb *) skb->cb;
 150
 151         IRDA_DEBUG(2, "%s()\n", __func__ );
 152
 153         line = cb->line;
 154
 155         self = (struct ircomm_cb *) hashbin_lock_find(ircomm, line, NULL);
 156         if (!self) {
 157                 IRDA_DEBUG(2, "%s(), didn't find myself\n", __func__ );
 158                 return;
 159         }
 160
 161         IRDA_ASSERT(self != NULL, return;);
 162         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 163
 164         self->pkt_count--;
 165
 166         if ((self->pkt_count < 2) && (self->flow_status == FLOW_STOP)) {
 167                 IRDA_DEBUG(2, "%s(), asking TTY to start again!\n", __func__ );
 168                 self->flow_status = FLOW_START;
 169                 if (self->notify.flow_indication)
 170                         self->notify.flow_indication(self->notify.instance,
 171                                                      self, FLOW_START);
 172         }
 173 }
 174
 175 /*
 176  * Function ircomm_lmp_data_request (self, userdata)
 177  *
 178  *    Send data frame to peer device
 179  *
 180  */
 181 static int ircomm_lmp_data_request(struct ircomm_cb *self,
 182                                    struct sk_buff *skb,
 183                                    int not_used)
 184 {
 185         struct irda_skb_cb *cb;
 186         int ret;
 187
 188         IRDA_ASSERT(skb != NULL, return -1;);
 189
 190         cb = (struct irda_skb_cb *) skb->cb;
 191
 192         cb->line = self->line;
 193
 194         IRDA_DEBUG(4, "%s(), sending frame\n", __func__ );
 195
 196         /* Don't forget to refcount it - see ircomm_tty_do_softint() */
 197         skb_get(skb);
 198
 199         skb->destructor = ircomm_lmp_flow_control;
 200
 201         if ((self->pkt_count++ > 7) && (self->flow_status == FLOW_START)) {
 202                 IRDA_DEBUG(2, "%s(), asking TTY to slow down!\n", __func__ );
 203                 self->flow_status = FLOW_STOP;
 204                 if (self->notify.flow_indication)
 205                         self->notify.flow_indication(self->notify.instance,
 206                                                      self, FLOW_STOP);
 207         }
 208         ret = irlmp_data_request(self->lsap, skb);
 209         if (ret) {
 210                 IRDA_ERROR("%s(), failed\n", __func__);
 211                 /* irlmp_data_request already free the packet */
 212         }
 213
 214         return ret;
 215 }
 216
 217 /*
 218  * Function ircomm_lmp_data_indication (instance, sap, skb)
 219  *
 220  *    Incoming data which we must deliver to the state machine, to check
 221  *    we are still connected.
 222  */
 223 static int ircomm_lmp_data_indication(void *instance, void *sap,
 224                                       struct sk_buff *skb)
 225 {
 226         struct ircomm_cb *self = (struct ircomm_cb *) instance;
 227
 228         IRDA_DEBUG(4, "%s()\n", __func__ );
 229
 230         IRDA_ASSERT(self != NULL, return -1;);
 231         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return -1;);
 232         IRDA_ASSERT(skb != NULL, return -1;);
 233
 234         ircomm_do_event(self, IRCOMM_LMP_DATA_INDICATION, skb, NULL);
 235
 236         /* Drop reference count - see ircomm_tty_data_indication(). */
 237         dev_kfree_skb(skb);
 238
 239         return 0;
 240 }
 241
 242 /*
 243  * Function ircomm_lmp_connect_confirm (instance, sap, qos, max_sdu_size,
 244  *                                       max_header_size, skb)
 245  *
 246  *    Connection has been confirmed by peer device
 247  *
 248  */
 249 static void ircomm_lmp_connect_confirm(void *instance, void *sap,
 250                                        struct qos_info *qos,
 251                                        __u32 max_seg_size,
 252                                        __u8 max_header_size,
 253                                        struct sk_buff *skb)
 254 {
 255         struct ircomm_cb *self = (struct ircomm_cb *) instance;
 256         struct ircomm_info info;
 257
 258         IRDA_DEBUG(0, "%s()\n", __func__ );
 259
 260         IRDA_ASSERT(self != NULL, return;);
 261         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 262         IRDA_ASSERT(skb != NULL, return;);
 263         IRDA_ASSERT(qos != NULL, return;);
 264
 265         info.max_data_size = max_seg_size;
 266         info.max_header_size = max_header_size;
 267         info.qos = qos;
 268
 269         ircomm_do_event(self, IRCOMM_LMP_CONNECT_CONFIRM, skb, &info);
 270
 271         /* Drop reference count - see ircomm_tty_connect_confirm(). */
 272         dev_kfree_skb(skb);
 273 }
 274
 275 /*
 276  * Function ircomm_lmp_connect_indication (instance, sap, qos, max_sdu_size,
 277  *                                         max_header_size, skb)
 278  *
 279  *    Peer device wants to make a connection with us
 280  *
 281  */
 282 static void ircomm_lmp_connect_indication(void *instance, void *sap,
 283                                           struct qos_info *qos,
 284                                           __u32 max_seg_size,
 285                                           __u8 max_header_size,
 286                                           struct sk_buff *skb)
 287 {
 288         struct ircomm_cb *self = (struct ircomm_cb *)instance;
 289         struct ircomm_info info;
 290
 291         IRDA_DEBUG(0, "%s()\n", __func__ );
 292
 293         IRDA_ASSERT(self != NULL, return;);
 294         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 295         IRDA_ASSERT(skb != NULL, return;);
 296         IRDA_ASSERT(qos != NULL, return;);
 297
 298         info.max_data_size = max_seg_size;
 299         info.max_header_size = max_header_size;
 300         info.qos = qos;
 301
 302         ircomm_do_event(self, IRCOMM_LMP_CONNECT_INDICATION, skb, &info);
 303
 304         /* Drop reference count - see ircomm_tty_connect_indication(). */
 305         dev_kfree_skb(skb);
 306 }
 307
 308 /*
 309  * Function ircomm_lmp_disconnect_indication (instance, sap, reason, skb)
 310  *
 311  *    Peer device has closed the connection, or the link went down for some
 312  *    other reason
 313  */
 314 static void ircomm_lmp_disconnect_indication(void *instance, void *sap,
 315                                              LM_REASON reason,
 316                                              struct sk_buff *skb)
 317 {
 318         struct ircomm_cb *self = (struct ircomm_cb *) instance;
 319         struct ircomm_info info;
 320
 321         IRDA_DEBUG(0, "%s()\n", __func__ );
 322
 323         IRDA_ASSERT(self != NULL, return;);
 324         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
 325
 326         info.reason = reason;
 327
 328         ircomm_do_event(self, IRCOMM_LMP_DISCONNECT_INDICATION, skb, &info);
 329
 330         /* Drop reference count - see ircomm_tty_disconnect_indication(). */
 331         if(skb)
 332                 dev_kfree_skb(skb);
 333 }
 334 /*
 335  * Function ircomm_open_lsap (self)
 336  *
 337  *    Open LSAP. This function will only be used when using "raw" services
 338  *
 339  */
 340 int ircomm_open_lsap(struct ircomm_cb *self)
 341 {
 342         notify_t notify;
 343
 344         IRDA_DEBUG(0, "%s()\n", __func__ );
 345
 346         /* Register callbacks */
 347         irda_notify_init(&notify);
 348         notify.data_indication       = ircomm_lmp_data_indication;
 349         notify.connect_confirm       = ircomm_lmp_connect_confirm;
 350         notify.connect_indication    = ircomm_lmp_connect_indication;
 351         notify.disconnect_indication = ircomm_lmp_disconnect_indication;
 352         notify.instance = self;
 353         strlcpy(notify.name, "IrCOMM", sizeof(notify.name));
 354
 355         self->lsap = irlmp_open_lsap(LSAP_ANY, &notify, 0);
 356         if (!self->lsap) {
 357                 IRDA_DEBUG(0,"%sfailed to allocate tsap\n", __func__ );
 358                 return -1;
 359         }
 360         self->slsap_sel = self->lsap->slsap_sel;
 361
 362         /*
 363          *  Initialize the call-table for issuing commands
 364          */
 365         self->issue.data_request       = ircomm_lmp_data_request;
 366         self->issue.connect_request    = ircomm_lmp_connect_request;
 367         self->issue.connect_response   = ircomm_lmp_connect_response;
 368         self->issue.disconnect_request = ircomm_lmp_disconnect_request;
 369
 370         return 0;
 371 }