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 }