net/irda/irlap.c

   1 /*********************************************************************
   2  *
   3  * Filename:      irlap.c
   4  * Version:       1.0
   5  * Description:   IrLAP implementation for Linux
   6  * Status:        Stable
   7  * Author:        Dag Brattli <dagb@cs.uit.no>
   8  * Created at:    Mon Aug  4 20:40:53 1997
   9  * Modified at:   Tue Dec 14 09:26:44 1999
  10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
  11  *
  12  *     Copyright (c) 1998-1999 Dag Brattli, All Rights Reserved.
  13  *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
  14  *
  15  *     This program is free software; you can redistribute it and/or
  16  *     modify it under the terms of the GNU General Public License as
  17  *     published by the Free Software Foundation; either version 2 of
  18  *     the License, or (at your option) any later version.
  19  *
  20  *     This program is distributed in the hope that it will be useful,
  21  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  23  *     GNU General Public License for more details.
  24  *
  25  *     You should have received a copy of the GNU General Public License
  26  *     along with this program; if not, see <http://www.gnu.org/licenses/>.
  27  *
  28  ********************************************************************/
  29
  30 #include <linux/slab.h>
  31 #include <linux/string.h>
  32 #include <linux/skbuff.h>
  33 #include <linux/delay.h>
  34 #include <linux/proc_fs.h>
  35 #include <linux/init.h>
  36 #include <linux/random.h>
  37 #include <linux/module.h>
  38 #include <linux/seq_file.h>
  39
  40 #include <net/irda/irda.h>
  41 #include <net/irda/irda_device.h>
  42 #include <net/irda/irqueue.h>
  43 #include <net/irda/irlmp.h>
  44 #include <net/irda/irlmp_frame.h>
  45 #include <net/irda/irlap_frame.h>
  46 #include <net/irda/irlap.h>
  47 #include <net/irda/timer.h>
  48 #include <net/irda/qos.h>
  49
  50 static hashbin_t *irlap = NULL;
  51 int sysctl_slot_timeout = SLOT_TIMEOUT * 1000 / HZ;
  52
  53 /* This is the delay of missed pf period before generating an event
  54  * to the application. The spec mandate 3 seconds, but in some cases
  55  * it's way too long. - Jean II */
  56 int sysctl_warn_noreply_time = 3;
  57
  58 extern void irlap_queue_xmit(struct irlap_cb *self, struct sk_buff *skb);
  59 static void __irlap_close(struct irlap_cb *self);
  60 static void irlap_init_qos_capabilities(struct irlap_cb *self,
  61                                         struct qos_info *qos_user);
  62
  63 #ifdef CONFIG_IRDA_DEBUG
  64 static const char *const lap_reasons[] = {
  65         "ERROR, NOT USED",
  66         "LAP_DISC_INDICATION",
  67         "LAP_NO_RESPONSE",
  68         "LAP_RESET_INDICATION",
  69         "LAP_FOUND_NONE",
  70         "LAP_MEDIA_BUSY",
  71         "LAP_PRIMARY_CONFLICT",
  72         "ERROR, NOT USED",
  73 };
  74 #endif  /* CONFIG_IRDA_DEBUG */
  75
  76 int __init irlap_init(void)
  77 {
  78         /* Check if the compiler did its job properly.
  79          * May happen on some ARM configuration, check with Russell King. */
  80         IRDA_ASSERT(sizeof(struct xid_frame) == 14, ;);
  81         IRDA_ASSERT(sizeof(struct test_frame) == 10, ;);
  82         IRDA_ASSERT(sizeof(struct ua_frame) == 10, ;);
  83         IRDA_ASSERT(sizeof(struct snrm_frame) == 11, ;);
  84
  85         /* Allocate master array */
  86         irlap = hashbin_new(HB_LOCK);
  87         if (irlap == NULL) {
  88                 net_err_ratelimited("%s: can't allocate irlap hashbin!\n",
  89                                     __func__);
  90                 return -ENOMEM;
  91         }
  92
  93         return 0;
  94 }
  95
  96 void irlap_cleanup(void)
  97 {
  98         IRDA_ASSERT(irlap != NULL, return;);
  99
 100         hashbin_delete(irlap, (FREE_FUNC) __irlap_close);
 101 }
 102
 103 /*
 104  * Function irlap_open (driver)
 105  *
 106  *    Initialize IrLAP layer
 107  *
 108  */
 109 struct irlap_cb *irlap_open(struct net_device *dev, struct qos_info *qos,
 110                             const char *hw_name)
 111 {
 112         struct irlap_cb *self;
 113
 114         /* Initialize the irlap structure. */
 115         self = kzalloc(sizeof(struct irlap_cb), GFP_KERNEL);
 116         if (self == NULL)
 117                 return NULL;
 118
 119         self->magic = LAP_MAGIC;
 120
 121         /* Make a binding between the layers */
 122         self->netdev = dev;
 123         self->qos_dev = qos;
 124         /* Copy hardware name */
 125         if(hw_name != NULL) {
 126                 strlcpy(self->hw_name, hw_name, sizeof(self->hw_name));
 127         } else {
 128                 self->hw_name[0] = '\0';
 129         }
 130
 131         /* FIXME: should we get our own field? */
 132         dev->atalk_ptr = self;
 133
 134         self->state = LAP_OFFLINE;
 135
 136         /* Initialize transmit queue */
 137         skb_queue_head_init(&self->txq);
 138         skb_queue_head_init(&self->txq_ultra);
 139         skb_queue_head_init(&self->wx_list);
 140
 141         /* My unique IrLAP device address! */
 142         /* We don't want the broadcast address, neither the NULL address
 143          * (most often used to signify "invalid"), and we don't want an
 144          * address already in use (otherwise connect won't be able
 145          * to select the proper link). - Jean II */
 146         do {
 147                 get_random_bytes(&self->saddr, sizeof(self->saddr));
 148         } while ((self->saddr == 0x0) || (self->saddr == BROADCAST) ||
 149                  (hashbin_lock_find(irlap, self->saddr, NULL)) );
 150         /* Copy to the driver */
 151         memcpy(dev->dev_addr, &self->saddr, 4);
 152
 153         init_timer(&self->slot_timer);
 154         init_timer(&self->query_timer);
 155         init_timer(&self->discovery_timer);
 156         init_timer(&self->final_timer);
 157         init_timer(&self->poll_timer);
 158         init_timer(&self->wd_timer);
 159         init_timer(&self->backoff_timer);
 160         init_timer(&self->media_busy_timer);
 161
 162         irlap_apply_default_connection_parameters(self);
 163
 164         self->N3 = 3; /* # connections attempts to try before giving up */
 165
 166         self->state = LAP_NDM;
 167
 168         hashbin_insert(irlap, (irda_queue_t *) self, self->saddr, NULL);
 169
 170         irlmp_register_link(self, self->saddr, &self->notify);
 171
 172         return self;
 173 }
 174 EXPORT_SYMBOL(irlap_open);
 175
 176 /*
 177  * Function __irlap_close (self)
 178  *
 179  *    Remove IrLAP and all allocated memory. Stop any pending timers.
 180  *
 181  */
 182 static void __irlap_close(struct irlap_cb *self)
 183 {
 184         IRDA_ASSERT(self != NULL, return;);
 185         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 186
 187         /* Stop timers */
 188         del_timer(&self->slot_timer);
 189         del_timer(&self->query_timer);
 190         del_timer(&self->discovery_timer);
 191         del_timer(&self->final_timer);
 192         del_timer(&self->poll_timer);
 193         del_timer(&self->wd_timer);
 194         del_timer(&self->backoff_timer);
 195         del_timer(&self->media_busy_timer);
 196
 197         irlap_flush_all_queues(self);
 198
 199         self->magic = 0;
 200
 201         kfree(self);
 202 }
 203
 204 /*
 205  * Function irlap_close (self)
 206  *
 207  *    Remove IrLAP instance
 208  *
 209  */
 210 void irlap_close(struct irlap_cb *self)
 211 {
 212         struct irlap_cb *lap;
 213
 214         IRDA_ASSERT(self != NULL, return;);
 215         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 216
 217         /* We used to send a LAP_DISC_INDICATION here, but this was
 218          * racy. This has been move within irlmp_unregister_link()
 219          * itself. Jean II */
 220
 221         /* Kill the LAP and all LSAPs on top of it */
 222         irlmp_unregister_link(self->saddr);
 223         self->notify.instance = NULL;
 224
 225         /* Be sure that we manage to remove ourself from the hash */
 226         lap = hashbin_remove(irlap, self->saddr, NULL);
 227         if (!lap) {
 228                 pr_debug("%s(), Didn't find myself!\n", __func__);
 229                 return;
 230         }
 231         __irlap_close(lap);
 232 }
 233 EXPORT_SYMBOL(irlap_close);
 234
 235 /*
 236  * Function irlap_connect_indication (self, skb)
 237  *
 238  *    Another device is attempting to make a connection
 239  *
 240  */
 241 void irlap_connect_indication(struct irlap_cb *self, struct sk_buff *skb)
 242 {
 243         IRDA_ASSERT(self != NULL, return;);
 244         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 245
 246         irlap_init_qos_capabilities(self, NULL); /* No user QoS! */
 247
 248         irlmp_link_connect_indication(self->notify.instance, self->saddr,
 249                                       self->daddr, &self->qos_tx, skb);
 250 }
 251
 252 /*
 253  * Function irlap_connect_response (self, skb)
 254  *
 255  *    Service user has accepted incoming connection
 256  *
 257  */
 258 void irlap_connect_response(struct irlap_cb *self, struct sk_buff *userdata)
 259 {
 260         irlap_do_event(self, CONNECT_RESPONSE, userdata, NULL);
 261 }
 262
 263 /*
 264  * Function irlap_connect_request (self, daddr, qos_user, sniff)
 265  *
 266  *    Request connection with another device, sniffing is not implemented
 267  *    yet.
 268  *
 269  */
 270 void irlap_connect_request(struct irlap_cb *self, __u32 daddr,
 271                            struct qos_info *qos_user, int sniff)
 272 {
 273         pr_debug("%s(), daddr=0x%08x\n", __func__, daddr);
 274
 275         IRDA_ASSERT(self != NULL, return;);
 276         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 277
 278         self->daddr = daddr;
 279
 280         /*
 281          *  If the service user specifies QoS values for this connection,
 282          *  then use them
 283          */
 284         irlap_init_qos_capabilities(self, qos_user);
 285
 286         if ((self->state == LAP_NDM) && !self->media_busy)
 287                 irlap_do_event(self, CONNECT_REQUEST, NULL, NULL);
 288         else
 289                 self->connect_pending = TRUE;
 290 }
 291
 292 /*
 293  * Function irlap_connect_confirm (self, skb)
 294  *
 295  *    Connection request has been accepted
 296  *
 297  */
 298 void irlap_connect_confirm(struct irlap_cb *self, struct sk_buff *skb)
 299 {
 300         IRDA_ASSERT(self != NULL, return;);
 301         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 302
 303         irlmp_link_connect_confirm(self->notify.instance, &self->qos_tx, skb);
 304 }
 305
 306 /*
 307  * Function irlap_data_indication (self, skb)
 308  *
 309  *    Received data frames from IR-port, so we just pass them up to
 310  *    IrLMP for further processing
 311  *
 312  */
 313 void irlap_data_indication(struct irlap_cb *self, struct sk_buff *skb,
 314                            int unreliable)
 315 {
 316         /* Hide LAP header from IrLMP layer */
 317         skb_pull(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
 318
 319         irlmp_link_data_indication(self->notify.instance, skb, unreliable);
 320 }
 321
 322
 323 /*
 324  * Function irlap_data_request (self, skb)
 325  *
 326  *    Queue data for transmission, must wait until XMIT state
 327  *
 328  */
 329 void irlap_data_request(struct irlap_cb *self, struct sk_buff *skb,
 330                         int unreliable)
 331 {
 332         IRDA_ASSERT(self != NULL, return;);
 333         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 334
 335         IRDA_ASSERT(skb_headroom(skb) >= (LAP_ADDR_HEADER+LAP_CTRL_HEADER),
 336                     return;);
 337         skb_push(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
 338
 339         /*
 340          *  Must set frame format now so that the rest of the code knows
 341          *  if its dealing with an I or an UI frame
 342          */
 343         if (unreliable)
 344                 skb->data[1] = UI_FRAME;
 345         else
 346                 skb->data[1] = I_FRAME;
 347
 348         /* Don't forget to refcount it - see irlmp_connect_request(). */
 349         skb_get(skb);
 350
 351         /* Add at the end of the queue (keep ordering) - Jean II */
 352         skb_queue_tail(&self->txq, skb);
 353
 354         /*
 355          *  Send event if this frame only if we are in the right state
 356          *  FIXME: udata should be sent first! (skb_queue_head?)
 357          */
 358         if ((self->state == LAP_XMIT_P) || (self->state == LAP_XMIT_S)) {
 359                 /* If we are not already processing the Tx queue, trigger
 360                  * transmission immediately - Jean II */
 361                 if((skb_queue_len(&self->txq) <= 1) && (!self->local_busy))
 362                         irlap_do_event(self, DATA_REQUEST, skb, NULL);
 363                 /* Otherwise, the packets will be sent normally at the
 364                  * next pf-poll - Jean II */
 365         }
 366 }
 367
 368 /*
 369  * Function irlap_unitdata_request (self, skb)
 370  *
 371  *    Send Ultra data. This is data that must be sent outside any connection
 372  *
 373  */
 374 #ifdef CONFIG_IRDA_ULTRA
 375 void irlap_unitdata_request(struct irlap_cb *self, struct sk_buff *skb)
 376 {
 377         IRDA_ASSERT(self != NULL, return;);
 378         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 379
 380         IRDA_ASSERT(skb_headroom(skb) >= (LAP_ADDR_HEADER+LAP_CTRL_HEADER),
 381                return;);
 382         skb_push(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
 383
 384         skb->data[0] = CBROADCAST;
 385         skb->data[1] = UI_FRAME;
 386
 387         /* Don't need to refcount, see irlmp_connless_data_request() */
 388
 389         skb_queue_tail(&self->txq_ultra, skb);
 390
 391         irlap_do_event(self, SEND_UI_FRAME, NULL, NULL);
 392 }
 393 #endif /*CONFIG_IRDA_ULTRA */
 394
 395 /*
 396  * Function irlap_udata_indication (self, skb)
 397  *
 398  *    Receive Ultra data. This is data that is received outside any connection
 399  *
 400  */
 401 #ifdef CONFIG_IRDA_ULTRA
 402 void irlap_unitdata_indication(struct irlap_cb *self, struct sk_buff *skb)
 403 {
 404         IRDA_ASSERT(self != NULL, return;);
 405         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 406         IRDA_ASSERT(skb != NULL, return;);
 407
 408         /* Hide LAP header from IrLMP layer */
 409         skb_pull(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
 410
 411         irlmp_link_unitdata_indication(self->notify.instance, skb);
 412 }
 413 #endif /* CONFIG_IRDA_ULTRA */
 414
 415 /*
 416  * Function irlap_disconnect_request (void)
 417  *
 418  *    Request to disconnect connection by service user
 419  */
 420 void irlap_disconnect_request(struct irlap_cb *self)
 421 {
 422         IRDA_ASSERT(self != NULL, return;);
 423         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 424
 425         /* Don't disconnect until all data frames are successfully sent */
 426         if (!skb_queue_empty(&self->txq)) {
 427                 self->disconnect_pending = TRUE;
 428                 return;
 429         }
 430
 431         /* Check if we are in the right state for disconnecting */
 432         switch (self->state) {
 433         case LAP_XMIT_P:        /* FALLTHROUGH */
 434         case LAP_XMIT_S:        /* FALLTHROUGH */
 435         case LAP_CONN:          /* FALLTHROUGH */
 436         case LAP_RESET_WAIT:    /* FALLTHROUGH */
 437         case LAP_RESET_CHECK:
 438                 irlap_do_event(self, DISCONNECT_REQUEST, NULL, NULL);
 439                 break;
 440         default:
 441                 pr_debug("%s(), disconnect pending!\n", __func__);
 442                 self->disconnect_pending = TRUE;
 443                 break;
 444         }
 445 }
 446
 447 /*
 448  * Function irlap_disconnect_indication (void)
 449  *
 450  *    Disconnect request from other device
 451  *
 452  */
 453 void irlap_disconnect_indication(struct irlap_cb *self, LAP_REASON reason)
 454 {
 455         pr_debug("%s(), reason=%s\n", __func__, lap_reasons[reason]);
 456
 457         IRDA_ASSERT(self != NULL, return;);
 458         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 459
 460         /* Flush queues */
 461         irlap_flush_all_queues(self);
 462
 463         switch (reason) {
 464         case LAP_RESET_INDICATION:
 465                 pr_debug("%s(), Sending reset request!\n", __func__);
 466                 irlap_do_event(self, RESET_REQUEST, NULL, NULL);
 467                 break;
 468         case LAP_NO_RESPONSE:      /* FALLTHROUGH */
 469         case LAP_DISC_INDICATION:  /* FALLTHROUGH */
 470         case LAP_FOUND_NONE:       /* FALLTHROUGH */
 471         case LAP_MEDIA_BUSY:
 472                 irlmp_link_disconnect_indication(self->notify.instance, self,
 473                                                  reason, NULL);
 474                 break;
 475         default:
 476                 net_err_ratelimited("%s: Unknown reason %d\n",
 477                                     __func__, reason);
 478         }
 479 }
 480
 481 /*
 482  * Function irlap_discovery_request (gen_addr_bit)
 483  *
 484  *    Start one single discovery operation.
 485  *
 486  */
 487 void irlap_discovery_request(struct irlap_cb *self, discovery_t *discovery)
 488 {
 489         struct irlap_info info;
 490
 491         IRDA_ASSERT(self != NULL, return;);
 492         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 493         IRDA_ASSERT(discovery != NULL, return;);
 494
 495         pr_debug("%s(), nslots = %d\n", __func__, discovery->nslots);
 496
 497         IRDA_ASSERT((discovery->nslots == 1) || (discovery->nslots == 6) ||
 498                     (discovery->nslots == 8) || (discovery->nslots == 16),
 499                     return;);
 500
 501         /* Discovery is only possible in NDM mode */
 502         if (self->state != LAP_NDM) {
 503                 pr_debug("%s(), discovery only possible in NDM mode\n",
 504                          __func__);
 505                 irlap_discovery_confirm(self, NULL);
 506                 /* Note : in theory, if we are not in NDM, we could postpone
 507                  * the discovery like we do for connection request.
 508                  * In practice, it's not worth it. If the media was busy,
 509                  * it's likely next time around it won't be busy. If we are
 510                  * in REPLY state, we will get passive discovery info & event.
 511                  * Jean II */
 512                 return;
 513         }
 514
 515         /* Check if last discovery request finished in time, or if
 516          * it was aborted due to the media busy flag. */
 517         if (self->discovery_log != NULL) {
 518                 hashbin_delete(self->discovery_log, (FREE_FUNC) kfree);
 519                 self->discovery_log = NULL;
 520         }
 521
 522         /* All operations will occur at predictable time, no need to lock */
 523         self->discovery_log = hashbin_new(HB_NOLOCK);
 524
 525         if (self->discovery_log == NULL) {
 526                 net_warn_ratelimited("%s(), Unable to allocate discovery log!\n",
 527                                      __func__);
 528                 return;
 529         }
 530
 531         info.S = discovery->nslots; /* Number of slots */
 532         info.s = 0; /* Current slot */
 533
 534         self->discovery_cmd = discovery;
 535         info.discovery = discovery;
 536
 537         /* sysctl_slot_timeout bounds are checked in irsysctl.c - Jean II */
 538         self->slot_timeout = sysctl_slot_timeout * HZ / 1000;
 539
 540         irlap_do_event(self, DISCOVERY_REQUEST, NULL, &info);
 541 }
 542
 543 /*
 544  * Function irlap_discovery_confirm (log)
 545  *
 546  *    A device has been discovered in front of this station, we
 547  *    report directly to LMP.
 548  */
 549 void irlap_discovery_confirm(struct irlap_cb *self, hashbin_t *discovery_log)
 550 {
 551         IRDA_ASSERT(self != NULL, return;);
 552         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 553
 554         IRDA_ASSERT(self->notify.instance != NULL, return;);
 555
 556         /*
 557          * Check for successful discovery, since we are then allowed to clear
 558          * the media busy condition (IrLAP 6.13.4 - p.94). This should allow
 559          * us to make connection attempts much faster and easier (i.e. no
 560          * collisions).
 561          * Setting media busy to false will also generate an event allowing
 562          * to process pending events in NDM state machine.
 563          * Note : the spec doesn't define what's a successful discovery is.
 564          * If we want Ultra to work, it's successful even if there is
 565          * nobody discovered - Jean II
 566          */
 567         if (discovery_log)
 568                 irda_device_set_media_busy(self->netdev, FALSE);
 569
 570         /* Inform IrLMP */
 571         irlmp_link_discovery_confirm(self->notify.instance, discovery_log);
 572 }
 573
 574 /*
 575  * Function irlap_discovery_indication (log)
 576  *
 577  *    Somebody is trying to discover us!
 578  *
 579  */
 580 void irlap_discovery_indication(struct irlap_cb *self, discovery_t *discovery)
 581 {
 582         IRDA_ASSERT(self != NULL, return;);
 583         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 584         IRDA_ASSERT(discovery != NULL, return;);
 585
 586         IRDA_ASSERT(self->notify.instance != NULL, return;);
 587
 588         /* A device is very likely to connect immediately after it performs
 589          * a successful discovery. This means that in our case, we are much
 590          * more likely to receive a connection request over the medium.
 591          * So, we backoff to avoid collisions.
 592          * IrLAP spec 6.13.4 suggest 100ms...
 593          * Note : this little trick actually make a *BIG* difference. If I set
 594          * my Linux box with discovery enabled and one Ultra frame sent every
 595          * second, my Palm has no trouble connecting to it every time !
 596          * Jean II */
 597         irda_device_set_media_busy(self->netdev, SMALL);
 598
 599         irlmp_link_discovery_indication(self->notify.instance, discovery);
 600 }
 601
 602 /*
 603  * Function irlap_status_indication (quality_of_link)
 604  */
 605 void irlap_status_indication(struct irlap_cb *self, int quality_of_link)
 606 {
 607         switch (quality_of_link) {
 608         case STATUS_NO_ACTIVITY:
 609                 net_info_ratelimited("IrLAP, no activity on link!\n");
 610                 break;
 611         case STATUS_NOISY:
 612                 net_info_ratelimited("IrLAP, noisy link!\n");
 613                 break;
 614         default:
 615                 break;
 616         }
 617         irlmp_status_indication(self->notify.instance,
 618                                 quality_of_link, LOCK_NO_CHANGE);
 619 }
 620
 621 /*
 622  * Function irlap_reset_indication (void)
 623  */
 624 void irlap_reset_indication(struct irlap_cb *self)
 625 {
 626         IRDA_ASSERT(self != NULL, return;);
 627         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 628
 629         if (self->state == LAP_RESET_WAIT)
 630                 irlap_do_event(self, RESET_REQUEST, NULL, NULL);
 631         else
 632                 irlap_do_event(self, RESET_RESPONSE, NULL, NULL);
 633 }
 634
 635 /*
 636  * Function irlap_reset_confirm (void)
 637  */
 638 void irlap_reset_confirm(void)
 639 {
 640 }
 641
 642 /*
 643  * Function irlap_generate_rand_time_slot (S, s)
 644  *
 645  *    Generate a random time slot between s and S-1 where
 646  *    S = Number of slots (0 -> S-1)
 647  *    s = Current slot
 648  */
 649 int irlap_generate_rand_time_slot(int S, int s)
 650 {
 651         static int rand;
 652         int slot;
 653
 654         IRDA_ASSERT((S - s) > 0, return 0;);
 655
 656         rand += jiffies;
 657         rand ^= (rand << 12);
 658         rand ^= (rand >> 20);
 659
 660         slot = s + rand % (S-s);
 661
 662         IRDA_ASSERT((slot >= s) || (slot < S), return 0;);
 663
 664         return slot;
 665 }
 666
 667 /*
 668  * Function irlap_update_nr_received (nr)
 669  *
 670  *    Remove all acknowledged frames in current window queue. This code is
 671  *    not intuitive and you should not try to change it. If you think it
 672  *    contains bugs, please mail a patch to the author instead.
 673  */
 674 void irlap_update_nr_received(struct irlap_cb *self, int nr)
 675 {
 676         struct sk_buff *skb = NULL;
 677         int count = 0;
 678
 679         /*
 680          * Remove all the ack-ed frames from the window queue.
 681          */
 682
 683         /*
 684          *  Optimize for the common case. It is most likely that the receiver
 685          *  will acknowledge all the frames we have sent! So in that case we
 686          *  delete all frames stored in window.
 687          */
 688         if (nr == self->vs) {
 689                 while ((skb = skb_dequeue(&self->wx_list)) != NULL) {
 690                         dev_kfree_skb(skb);
 691                 }
 692                 /* The last acked frame is the next to send minus one */
 693                 self->va = nr - 1;
 694         } else {
 695                 /* Remove all acknowledged frames in current window */
 696                 while ((skb_peek(&self->wx_list) != NULL) &&
 697                        (((self->va+1) % 8) != nr))
 698                 {
 699                         skb = skb_dequeue(&self->wx_list);
 700                         dev_kfree_skb(skb);
 701
 702                         self->va = (self->va + 1) % 8;
 703                         count++;
 704                 }
 705         }
 706
 707         /* Advance window */
 708         self->window = self->window_size - skb_queue_len(&self->wx_list);
 709 }
 710
 711 /*
 712  * Function irlap_validate_ns_received (ns)
 713  *
 714  *    Validate the next to send (ns) field from received frame.
 715  */
 716 int irlap_validate_ns_received(struct irlap_cb *self, int ns)
 717 {
 718         /*  ns as expected?  */
 719         if (ns == self->vr)
 720                 return NS_EXPECTED;
 721         /*
 722          *  Stations are allowed to treat invalid NS as unexpected NS
 723          *  IrLAP, Recv ... with-invalid-Ns. p. 84
 724          */
 725         return NS_UNEXPECTED;
 726
 727         /* return NR_INVALID; */
 728 }
 729 /*
 730  * Function irlap_validate_nr_received (nr)
 731  *
 732  *    Validate the next to receive (nr) field from received frame.
 733  *
 734  */
 735 int irlap_validate_nr_received(struct irlap_cb *self, int nr)
 736 {
 737         /*  nr as expected?  */
 738         if (nr == self->vs) {
 739                 pr_debug("%s(), expected!\n", __func__);
 740                 return NR_EXPECTED;
 741         }
 742
 743         /*
 744          *  unexpected nr? (but within current window), first we check if the
 745          *  ns numbers of the frames in the current window wrap.
 746          */
 747         if (self->va < self->vs) {
 748                 if ((nr >= self->va) && (nr <= self->vs))
 749                         return NR_UNEXPECTED;
 750         } else {
 751                 if ((nr >= self->va) || (nr <= self->vs))
 752                         return NR_UNEXPECTED;
 753         }
 754
 755         /* Invalid nr!  */
 756         return NR_INVALID;
 757 }
 758
 759 /*
 760  * Function irlap_initiate_connection_state ()
 761  *
 762  *    Initialize the connection state parameters
 763  *
 764  */
 765 void irlap_initiate_connection_state(struct irlap_cb *self)
 766 {
 767         IRDA_ASSERT(self != NULL, return;);
 768         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 769
 770         /* Next to send and next to receive */
 771         self->vs = self->vr = 0;
 772
 773         /* Last frame which got acked (0 - 1) % 8 */
 774         self->va = 7;
 775
 776         self->window = 1;
 777
 778         self->remote_busy = FALSE;
 779         self->retry_count = 0;
 780 }
 781
 782 /*
 783  * Function irlap_wait_min_turn_around (self, qos)
 784  *
 785  *    Wait negotiated minimum turn around time, this function actually sets
 786  *    the number of BOS's that must be sent before the next transmitted
 787  *    frame in order to delay for the specified amount of time. This is
 788  *    done to avoid using timers, and the forbidden udelay!
 789  */
 790 void irlap_wait_min_turn_around(struct irlap_cb *self, struct qos_info *qos)
 791 {
 792         __u32 min_turn_time;
 793         __u32 speed;
 794
 795         /* Get QoS values.  */
 796         speed = qos->baud_rate.value;
 797         min_turn_time = qos->min_turn_time.value;
 798
 799         /* No need to calculate XBOFs for speeds over 115200 bps */
 800         if (speed > 115200) {
 801                 self->mtt_required = min_turn_time;
 802                 return;
 803         }
 804
 805         /*
 806          *  Send additional BOF's for the next frame for the requested
 807          *  min turn time, so now we must calculate how many chars (XBOF's) we
 808          *  must send for the requested time period (min turn time)
 809          */
 810         self->xbofs_delay = irlap_min_turn_time_in_bytes(speed, min_turn_time);
 811 }
 812
 813 /*
 814  * Function irlap_flush_all_queues (void)
 815  *
 816  *    Flush all queues
 817  *
 818  */
 819 void irlap_flush_all_queues(struct irlap_cb *self)
 820 {
 821         struct sk_buff* skb;
 822
 823         IRDA_ASSERT(self != NULL, return;);
 824         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 825
 826         /* Free transmission queue */
 827         while ((skb = skb_dequeue(&self->txq)) != NULL)
 828                 dev_kfree_skb(skb);
 829
 830         while ((skb = skb_dequeue(&self->txq_ultra)) != NULL)
 831                 dev_kfree_skb(skb);
 832
 833         /* Free sliding window buffered packets */
 834         while ((skb = skb_dequeue(&self->wx_list)) != NULL)
 835                 dev_kfree_skb(skb);
 836 }
 837
 838 /*
 839  * Function irlap_setspeed (self, speed)
 840  *
 841  *    Change the speed of the IrDA port
 842  *
 843  */
 844 static void irlap_change_speed(struct irlap_cb *self, __u32 speed, int now)
 845 {
 846         struct sk_buff *skb;
 847
 848         pr_debug("%s(), setting speed to %d\n", __func__, speed);
 849
 850         IRDA_ASSERT(self != NULL, return;);
 851         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 852
 853         self->speed = speed;
 854
 855         /* Change speed now, or just piggyback speed on frames */
 856         if (now) {
 857                 /* Send down empty frame to trigger speed change */
 858                 skb = alloc_skb(0, GFP_ATOMIC);
 859                 if (skb)
 860                         irlap_queue_xmit(self, skb);
 861         }
 862 }
 863
 864 /*
 865  * Function irlap_init_qos_capabilities (self, qos)
 866  *
 867  *    Initialize QoS for this IrLAP session, What we do is to compute the
 868  *    intersection of the QoS capabilities for the user, driver and for
 869  *    IrLAP itself. Normally, IrLAP will not specify any values, but it can
 870  *    be used to restrict certain values.
 871  */
 872 static void irlap_init_qos_capabilities(struct irlap_cb *self,
 873                                         struct qos_info *qos_user)
 874 {
 875         IRDA_ASSERT(self != NULL, return;);
 876         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 877         IRDA_ASSERT(self->netdev != NULL, return;);
 878
 879         /* Start out with the maximum QoS support possible */
 880         irda_init_max_qos_capabilies(&self->qos_rx);
 881
 882         /* Apply drivers QoS capabilities */
 883         irda_qos_compute_intersection(&self->qos_rx, self->qos_dev);
 884
 885         /*
 886          *  Check for user supplied QoS parameters. The service user is only
 887          *  allowed to supply these values. We check each parameter since the
 888          *  user may not have set all of them.
 889          */
 890         if (qos_user) {
 891                 pr_debug("%s(), Found user specified QoS!\n", __func__);
 892
 893                 if (qos_user->baud_rate.bits)
 894                         self->qos_rx.baud_rate.bits &= qos_user->baud_rate.bits;
 895
 896                 if (qos_user->max_turn_time.bits)
 897                         self->qos_rx.max_turn_time.bits &= qos_user->max_turn_time.bits;
 898                 if (qos_user->data_size.bits)
 899                         self->qos_rx.data_size.bits &= qos_user->data_size.bits;
 900
 901                 if (qos_user->link_disc_time.bits)
 902                         self->qos_rx.link_disc_time.bits &= qos_user->link_disc_time.bits;
 903         }
 904
 905         /* Use 500ms in IrLAP for now */
 906         self->qos_rx.max_turn_time.bits &= 0x01;
 907
 908         /* Set data size */
 909         /*self->qos_rx.data_size.bits &= 0x03;*/
 910
 911         irda_qos_bits_to_value(&self->qos_rx);
 912 }
 913
 914 /*
 915  * Function irlap_apply_default_connection_parameters (void, now)
 916  *
 917  *    Use the default connection and transmission parameters
 918  */
 919 void irlap_apply_default_connection_parameters(struct irlap_cb *self)
 920 {
 921         IRDA_ASSERT(self != NULL, return;);
 922         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 923
 924         /* xbofs : Default value in NDM */
 925         self->next_bofs   = 12;
 926         self->bofs_count  = 12;
 927
 928         /* NDM Speed is 9600 */
 929         irlap_change_speed(self, 9600, TRUE);
 930
 931         /* Set mbusy when going to NDM state */
 932         irda_device_set_media_busy(self->netdev, TRUE);
 933
 934         /*
 935          * Generate random connection address for this session, which must
 936          * be 7 bits wide and different from 0x00 and 0xfe
 937          */
 938         while ((self->caddr == 0x00) || (self->caddr == 0xfe)) {
 939                 get_random_bytes(&self->caddr, sizeof(self->caddr));
 940                 self->caddr &= 0xfe;
 941         }
 942
 943         /* Use default values until connection has been negitiated */
 944         self->slot_timeout = sysctl_slot_timeout;
 945         self->final_timeout = FINAL_TIMEOUT;
 946         self->poll_timeout = POLL_TIMEOUT;
 947         self->wd_timeout = WD_TIMEOUT;
 948
 949         /* Set some default values */
 950         self->qos_tx.baud_rate.value = 9600;
 951         self->qos_rx.baud_rate.value = 9600;
 952         self->qos_tx.max_turn_time.value = 0;
 953         self->qos_rx.max_turn_time.value = 0;
 954         self->qos_tx.min_turn_time.value = 0;
 955         self->qos_rx.min_turn_time.value = 0;
 956         self->qos_tx.data_size.value = 64;
 957         self->qos_rx.data_size.value = 64;
 958         self->qos_tx.window_size.value = 1;
 959         self->qos_rx.window_size.value = 1;
 960         self->qos_tx.additional_bofs.value = 12;
 961         self->qos_rx.additional_bofs.value = 12;
 962         self->qos_tx.link_disc_time.value = 0;
 963         self->qos_rx.link_disc_time.value = 0;
 964
 965         irlap_flush_all_queues(self);
 966
 967         self->disconnect_pending = FALSE;
 968         self->connect_pending = FALSE;
 969 }
 970
 971 /*
 972  * Function irlap_apply_connection_parameters (qos, now)
 973  *
 974  *    Initialize IrLAP with the negotiated QoS values
 975  *
 976  * If 'now' is false, the speed and xbofs will be changed after the next
 977  * frame is sent.
 978  * If 'now' is true, the speed and xbofs is changed immediately
 979  */
 980 void irlap_apply_connection_parameters(struct irlap_cb *self, int now)
 981 {
 982         IRDA_ASSERT(self != NULL, return;);
 983         IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
 984
 985         /* Set the negotiated xbofs value */
 986         self->next_bofs   = self->qos_tx.additional_bofs.value;
 987         if (now)
 988                 self->bofs_count = self->next_bofs;
 989
 990         /* Set the negotiated link speed (may need the new xbofs value) */
 991         irlap_change_speed(self, self->qos_tx.baud_rate.value, now);
 992
 993         self->window_size = self->qos_tx.window_size.value;
 994         self->window      = self->qos_tx.window_size.value;
 995
 996 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
 997         /*
 998          *  Calculate how many bytes it is possible to transmit before the
 999          *  link must be turned around
1000          */
1001         self->line_capacity =
1002                 irlap_max_line_capacity(self->qos_tx.baud_rate.value,
1003                                         self->qos_tx.max_turn_time.value);
1004         self->bytes_left = self->line_capacity;
1005 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1006
1007
1008         /*
1009          *  Initialize timeout values, some of the rules are listed on
1010          *  page 92 in IrLAP.
1011          */
1012         IRDA_ASSERT(self->qos_tx.max_turn_time.value != 0, return;);
1013         IRDA_ASSERT(self->qos_rx.max_turn_time.value != 0, return;);
1014         /* The poll timeout applies only to the primary station.
1015          * It defines the maximum time the primary stay in XMIT mode
1016          * before timeout and turning the link around (sending a RR).
1017          * Or, this is how much we can keep the pf bit in primary mode.
1018          * Therefore, it must be lower or equal than our *OWN* max turn around.
1019          * Jean II */
1020         self->poll_timeout = self->qos_tx.max_turn_time.value * HZ / 1000;
1021         /* The Final timeout applies only to the primary station.
1022          * It defines the maximum time the primary wait (mostly in RECV mode)
1023          * for an answer from the secondary station before polling it again.
1024          * Therefore, it must be greater or equal than our *PARTNER*
1025          * max turn around time - Jean II */
1026         self->final_timeout = self->qos_rx.max_turn_time.value * HZ / 1000;
1027         /* The Watchdog Bit timeout applies only to the secondary station.
1028          * It defines the maximum time the secondary wait (mostly in RECV mode)
1029          * for poll from the primary station before getting annoyed.
1030          * Therefore, it must be greater or equal than our *PARTNER*
1031          * max turn around time - Jean II */
1032         self->wd_timeout = self->final_timeout * 2;
1033
1034         /*
1035          * N1 and N2 are maximum retry count for *both* the final timer
1036          * and the wd timer (with a factor 2) as defined above.
1037          * After N1 retry of a timer, we give a warning to the user.
1038          * After N2 retry, we consider the link dead and disconnect it.
1039          * Jean II
1040          */
1041
1042         /*
1043          *  Set N1 to 0 if Link Disconnect/Threshold Time = 3 and set it to
1044          *  3 seconds otherwise. See page 71 in IrLAP for more details.
1045          *  Actually, it's not always 3 seconds, as we allow to set
1046          *  it via sysctl... Max maxtt is 500ms, and N1 need to be multiple
1047          *  of 2, so 1 second is minimum we can allow. - Jean II
1048          */
1049         if (self->qos_tx.link_disc_time.value == sysctl_warn_noreply_time)
1050                 /*
1051                  * If we set N1 to 0, it will trigger immediately, which is
1052                  * not what we want. What we really want is to disable it,
1053                  * Jean II
1054                  */
1055                 self->N1 = -2; /* Disable - Need to be multiple of 2*/
1056         else
1057                 self->N1 = sysctl_warn_noreply_time * 1000 /
1058                   self->qos_rx.max_turn_time.value;
1059
1060         pr_debug("Setting N1 = %d\n", self->N1);
1061
1062         /* Set N2 to match our own disconnect time */
1063         self->N2 = self->qos_tx.link_disc_time.value * 1000 /
1064                 self->qos_rx.max_turn_time.value;
1065         pr_debug("Setting N2 = %d\n", self->N2);
1066 }
1067
1068 #ifdef CONFIG_PROC_FS
1069 struct irlap_iter_state {
1070         int id;
1071 };
1072
1073 static void *irlap_seq_start(struct seq_file *seq, loff_t *pos)
1074 {
1075         struct irlap_iter_state *iter = seq->private;
1076         struct irlap_cb *self;
1077
1078         /* Protect our access to the tsap list */
1079         spin_lock_irq(&irlap->hb_spinlock);
1080         iter->id = 0;
1081
1082         for (self = (struct irlap_cb *) hashbin_get_first(irlap);
1083              self; self = (struct irlap_cb *) hashbin_get_next(irlap)) {
1084                 if (iter->id == *pos)
1085                         break;
1086                 ++iter->id;
1087         }
1088
1089         return self;
1090 }
1091
1092 static void *irlap_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1093 {
1094         struct irlap_iter_state *iter = seq->private;
1095
1096         ++*pos;
1097         ++iter->id;
1098         return (void *) hashbin_get_next(irlap);
1099 }
1100
1101 static void irlap_seq_stop(struct seq_file *seq, void *v)
1102 {
1103         spin_unlock_irq(&irlap->hb_spinlock);
1104 }
1105
1106 static int irlap_seq_show(struct seq_file *seq, void *v)
1107 {
1108         const struct irlap_iter_state *iter = seq->private;
1109         const struct irlap_cb *self = v;
1110
1111         IRDA_ASSERT(self->magic == LAP_MAGIC, return -EINVAL;);
1112
1113         seq_printf(seq, "irlap%d ", iter->id);
1114         seq_printf(seq, "state: %s\n",
1115                    irlap_state[self->state]);
1116
1117         seq_printf(seq, "  device name: %s, ",
1118                    (self->netdev) ? self->netdev->name : "bug");
1119         seq_printf(seq, "hardware name: %s\n", self->hw_name);
1120
1121         seq_printf(seq, "  caddr: %#02x, ", self->caddr);
1122         seq_printf(seq, "saddr: %#08x, ", self->saddr);
1123         seq_printf(seq, "daddr: %#08x\n", self->daddr);
1124
1125         seq_printf(seq, "  win size: %d, ",
1126                    self->window_size);
1127         seq_printf(seq, "win: %d, ", self->window);
1128 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1129         seq_printf(seq, "line capacity: %d, ",
1130                    self->line_capacity);
1131         seq_printf(seq, "bytes left: %d\n", self->bytes_left);
1132 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1133         seq_printf(seq, "  tx queue len: %d ",
1134                    skb_queue_len(&self->txq));
1135         seq_printf(seq, "win queue len: %d ",
1136                    skb_queue_len(&self->wx_list));
1137         seq_printf(seq, "rbusy: %s", self->remote_busy ?
1138                    "TRUE" : "FALSE");
1139         seq_printf(seq, " mbusy: %s\n", self->media_busy ?
1140                    "TRUE" : "FALSE");
1141
1142         seq_printf(seq, "  retrans: %d ", self->retry_count);
1143         seq_printf(seq, "vs: %d ", self->vs);
1144         seq_printf(seq, "vr: %d ", self->vr);
1145         seq_printf(seq, "va: %d\n", self->va);
1146
1147         seq_printf(seq, "  qos\tbps\tmaxtt\tdsize\twinsize\taddbofs\tmintt\tldisc\tcomp\n");
1148
1149         seq_printf(seq, "  tx\t%d\t",
1150                    self->qos_tx.baud_rate.value);
1151         seq_printf(seq, "%d\t",
1152                    self->qos_tx.max_turn_time.value);
1153         seq_printf(seq, "%d\t",
1154                    self->qos_tx.data_size.value);
1155         seq_printf(seq, "%d\t",
1156                    self->qos_tx.window_size.value);
1157         seq_printf(seq, "%d\t",
1158                    self->qos_tx.additional_bofs.value);
1159         seq_printf(seq, "%d\t",
1160                    self->qos_tx.min_turn_time.value);
1161         seq_printf(seq, "%d\t",
1162                    self->qos_tx.link_disc_time.value);
1163         seq_printf(seq, "\n");
1164
1165         seq_printf(seq, "  rx\t%d\t",
1166                    self->qos_rx.baud_rate.value);
1167         seq_printf(seq, "%d\t",
1168                    self->qos_rx.max_turn_time.value);
1169         seq_printf(seq, "%d\t",
1170                    self->qos_rx.data_size.value);
1171         seq_printf(seq, "%d\t",
1172                    self->qos_rx.window_size.value);
1173         seq_printf(seq, "%d\t",
1174                    self->qos_rx.additional_bofs.value);
1175         seq_printf(seq, "%d\t",
1176                    self->qos_rx.min_turn_time.value);
1177         seq_printf(seq, "%d\n",
1178                    self->qos_rx.link_disc_time.value);
1179
1180         return 0;
1181 }
1182
1183 static const struct seq_operations irlap_seq_ops = {
1184         .start  = irlap_seq_start,
1185         .next   = irlap_seq_next,
1186         .stop   = irlap_seq_stop,
1187         .show   = irlap_seq_show,
1188 };
1189
1190 static int irlap_seq_open(struct inode *inode, struct file *file)
1191 {
1192         if (irlap == NULL)
1193                 return -EINVAL;
1194
1195         return seq_open_private(file, &irlap_seq_ops,
1196                         sizeof(struct irlap_iter_state));
1197 }
1198
1199 const struct file_operations irlap_seq_fops = {
1200         .owner          = THIS_MODULE,
1201         .open           = irlap_seq_open,
1202         .read           = seq_read,
1203         .llseek         = seq_lseek,
1204         .release        = seq_release_private,
1205 };
1206
1207 #endif /* CONFIG_PROC_FS */