Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame] | 1 | /********************************************************************* |
| 2 | * |
| 3 | * Filename: irttp.c |
| 4 | * Version: 1.2 |
| 5 | * Description: Tiny Transport Protocol (TTP) implementation |
| 6 | * Status: Stable |
| 7 | * Author: Dag Brattli <dagb@cs.uit.no> |
| 8 | * Created at: Sun Aug 31 20:14:31 1997 |
| 9 | * Modified at: Wed Jan 5 11:31:27 2000 |
| 10 | * Modified by: Dag Brattli <dagb@cs.uit.no> |
| 11 | * |
| 12 | * Copyright (c) 1998-2000 Dag Brattli <dagb@cs.uit.no>, |
| 13 | * 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 | * Neither Dag Brattli nor University of Tromsø admit liability nor |
| 22 | * provide warranty for any of this software. This material is |
| 23 | * provided "AS-IS" and at no charge. |
| 24 | * |
| 25 | ********************************************************************/ |
| 26 | |
| 27 | #include <linux/skbuff.h> |
| 28 | #include <linux/init.h> |
| 29 | #include <linux/fs.h> |
| 30 | #include <linux/seq_file.h> |
| 31 | #include <linux/slab.h> |
| 32 | #include <linux/export.h> |
| 33 | |
| 34 | #include <asm/byteorder.h> |
| 35 | #include <asm/unaligned.h> |
| 36 | |
| 37 | #include <net/irda/irda.h> |
| 38 | #include <net/irda/irlap.h> |
| 39 | #include <net/irda/irlmp.h> |
| 40 | #include <net/irda/parameters.h> |
| 41 | #include <net/irda/irttp.h> |
| 42 | |
| 43 | static struct irttp_cb *irttp; |
| 44 | |
| 45 | static void __irttp_close_tsap(struct tsap_cb *self); |
| 46 | |
| 47 | static int irttp_data_indication(void *instance, void *sap, |
| 48 | struct sk_buff *skb); |
| 49 | static int irttp_udata_indication(void *instance, void *sap, |
| 50 | struct sk_buff *skb); |
| 51 | static void irttp_disconnect_indication(void *instance, void *sap, |
| 52 | LM_REASON reason, struct sk_buff *); |
| 53 | static void irttp_connect_indication(void *instance, void *sap, |
| 54 | struct qos_info *qos, __u32 max_sdu_size, |
| 55 | __u8 header_size, struct sk_buff *skb); |
| 56 | static void irttp_connect_confirm(void *instance, void *sap, |
| 57 | struct qos_info *qos, __u32 max_sdu_size, |
| 58 | __u8 header_size, struct sk_buff *skb); |
| 59 | static void irttp_run_tx_queue(struct tsap_cb *self); |
| 60 | static void irttp_run_rx_queue(struct tsap_cb *self); |
| 61 | |
| 62 | static void irttp_flush_queues(struct tsap_cb *self); |
| 63 | static void irttp_fragment_skb(struct tsap_cb *self, struct sk_buff *skb); |
| 64 | static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self); |
| 65 | static void irttp_todo_expired(unsigned long data); |
| 66 | static int irttp_param_max_sdu_size(void *instance, irda_param_t *param, |
| 67 | int get); |
| 68 | |
| 69 | static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow); |
| 70 | static void irttp_status_indication(void *instance, |
| 71 | LINK_STATUS link, LOCK_STATUS lock); |
| 72 | |
| 73 | /* Information for parsing parameters in IrTTP */ |
| 74 | static const pi_minor_info_t pi_minor_call_table[] = { |
| 75 | { NULL, 0 }, /* 0x00 */ |
| 76 | { irttp_param_max_sdu_size, PV_INTEGER | PV_BIG_ENDIAN } /* 0x01 */ |
| 77 | }; |
| 78 | static const pi_major_info_t pi_major_call_table[] = { |
| 79 | { pi_minor_call_table, 2 } |
| 80 | }; |
| 81 | static pi_param_info_t param_info = { pi_major_call_table, 1, 0x0f, 4 }; |
| 82 | |
| 83 | /************************ GLOBAL PROCEDURES ************************/ |
| 84 | |
| 85 | /* |
| 86 | * Function irttp_init (void) |
| 87 | * |
| 88 | * Initialize the IrTTP layer. Called by module initialization code |
| 89 | * |
| 90 | */ |
| 91 | int __init irttp_init(void) |
| 92 | { |
| 93 | irttp = kzalloc(sizeof(struct irttp_cb), GFP_KERNEL); |
| 94 | if (irttp == NULL) |
| 95 | return -ENOMEM; |
| 96 | |
| 97 | irttp->magic = TTP_MAGIC; |
| 98 | |
| 99 | irttp->tsaps = hashbin_new(HB_LOCK); |
| 100 | if (!irttp->tsaps) { |
| 101 | net_err_ratelimited("%s: can't allocate IrTTP hashbin!\n", |
| 102 | __func__); |
| 103 | kfree(irttp); |
| 104 | return -ENOMEM; |
| 105 | } |
| 106 | |
| 107 | return 0; |
| 108 | } |
| 109 | |
| 110 | /* |
| 111 | * Function irttp_cleanup (void) |
| 112 | * |
| 113 | * Called by module destruction/cleanup code |
| 114 | * |
| 115 | */ |
| 116 | void irttp_cleanup(void) |
| 117 | { |
| 118 | /* Check for main structure */ |
| 119 | IRDA_ASSERT(irttp->magic == TTP_MAGIC, return;); |
| 120 | |
| 121 | /* |
| 122 | * Delete hashbin and close all TSAP instances in it |
| 123 | */ |
| 124 | hashbin_delete(irttp->tsaps, (FREE_FUNC) __irttp_close_tsap); |
| 125 | |
| 126 | irttp->magic = 0; |
| 127 | |
| 128 | /* De-allocate main structure */ |
| 129 | kfree(irttp); |
| 130 | |
| 131 | irttp = NULL; |
| 132 | } |
| 133 | |
| 134 | /*************************** SUBROUTINES ***************************/ |
| 135 | |
| 136 | /* |
| 137 | * Function irttp_start_todo_timer (self, timeout) |
| 138 | * |
| 139 | * Start todo timer. |
| 140 | * |
| 141 | * Made it more effient and unsensitive to race conditions - Jean II |
| 142 | */ |
| 143 | static inline void irttp_start_todo_timer(struct tsap_cb *self, int timeout) |
| 144 | { |
| 145 | /* Set new value for timer */ |
| 146 | mod_timer(&self->todo_timer, jiffies + timeout); |
| 147 | } |
| 148 | |
| 149 | /* |
| 150 | * Function irttp_todo_expired (data) |
| 151 | * |
| 152 | * Todo timer has expired! |
| 153 | * |
| 154 | * One of the restriction of the timer is that it is run only on the timer |
| 155 | * interrupt which run every 10ms. This mean that even if you set the timer |
| 156 | * with a delay of 0, it may take up to 10ms before it's run. |
| 157 | * So, to minimise latency and keep cache fresh, we try to avoid using |
| 158 | * it as much as possible. |
| 159 | * Note : we can't use tasklets, because they can't be asynchronously |
| 160 | * killed (need user context), and we can't guarantee that here... |
| 161 | * Jean II |
| 162 | */ |
| 163 | static void irttp_todo_expired(unsigned long data) |
| 164 | { |
| 165 | struct tsap_cb *self = (struct tsap_cb *) data; |
| 166 | |
| 167 | /* Check that we still exist */ |
| 168 | if (!self || self->magic != TTP_TSAP_MAGIC) |
| 169 | return; |
| 170 | |
| 171 | pr_debug("%s(instance=%p)\n", __func__, self); |
| 172 | |
| 173 | /* Try to make some progress, especially on Tx side - Jean II */ |
| 174 | irttp_run_rx_queue(self); |
| 175 | irttp_run_tx_queue(self); |
| 176 | |
| 177 | /* Check if time for disconnect */ |
| 178 | if (test_bit(0, &self->disconnect_pend)) { |
| 179 | /* Check if it's possible to disconnect yet */ |
| 180 | if (skb_queue_empty(&self->tx_queue)) { |
| 181 | /* Make sure disconnect is not pending anymore */ |
| 182 | clear_bit(0, &self->disconnect_pend); /* FALSE */ |
| 183 | |
| 184 | /* Note : self->disconnect_skb may be NULL */ |
| 185 | irttp_disconnect_request(self, self->disconnect_skb, |
| 186 | P_NORMAL); |
| 187 | self->disconnect_skb = NULL; |
| 188 | } else { |
| 189 | /* Try again later */ |
| 190 | irttp_start_todo_timer(self, HZ/10); |
| 191 | |
| 192 | /* No reason to try and close now */ |
| 193 | return; |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | /* Check if it's closing time */ |
| 198 | if (self->close_pend) |
| 199 | /* Finish cleanup */ |
| 200 | irttp_close_tsap(self); |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * Function irttp_flush_queues (self) |
| 205 | * |
| 206 | * Flushes (removes all frames) in transitt-buffer (tx_list) |
| 207 | */ |
| 208 | static void irttp_flush_queues(struct tsap_cb *self) |
| 209 | { |
| 210 | struct sk_buff *skb; |
| 211 | |
| 212 | IRDA_ASSERT(self != NULL, return;); |
| 213 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 214 | |
| 215 | /* Deallocate frames waiting to be sent */ |
| 216 | while ((skb = skb_dequeue(&self->tx_queue)) != NULL) |
| 217 | dev_kfree_skb(skb); |
| 218 | |
| 219 | /* Deallocate received frames */ |
| 220 | while ((skb = skb_dequeue(&self->rx_queue)) != NULL) |
| 221 | dev_kfree_skb(skb); |
| 222 | |
| 223 | /* Deallocate received fragments */ |
| 224 | while ((skb = skb_dequeue(&self->rx_fragments)) != NULL) |
| 225 | dev_kfree_skb(skb); |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | * Function irttp_reassemble (self) |
| 230 | * |
| 231 | * Makes a new (continuous) skb of all the fragments in the fragment |
| 232 | * queue |
| 233 | * |
| 234 | */ |
| 235 | static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self) |
| 236 | { |
| 237 | struct sk_buff *skb, *frag; |
| 238 | int n = 0; /* Fragment index */ |
| 239 | |
| 240 | IRDA_ASSERT(self != NULL, return NULL;); |
| 241 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return NULL;); |
| 242 | |
| 243 | pr_debug("%s(), self->rx_sdu_size=%d\n", __func__, |
| 244 | self->rx_sdu_size); |
| 245 | |
| 246 | skb = dev_alloc_skb(TTP_HEADER + self->rx_sdu_size); |
| 247 | if (!skb) |
| 248 | return NULL; |
| 249 | |
| 250 | /* |
| 251 | * Need to reserve space for TTP header in case this skb needs to |
| 252 | * be requeued in case delivery failes |
| 253 | */ |
| 254 | skb_reserve(skb, TTP_HEADER); |
| 255 | skb_put(skb, self->rx_sdu_size); |
| 256 | |
| 257 | /* |
| 258 | * Copy all fragments to a new buffer |
| 259 | */ |
| 260 | while ((frag = skb_dequeue(&self->rx_fragments)) != NULL) { |
| 261 | skb_copy_to_linear_data_offset(skb, n, frag->data, frag->len); |
| 262 | n += frag->len; |
| 263 | |
| 264 | dev_kfree_skb(frag); |
| 265 | } |
| 266 | |
| 267 | pr_debug("%s(), frame len=%d, rx_sdu_size=%d, rx_max_sdu_size=%d\n", |
| 268 | __func__, n, self->rx_sdu_size, self->rx_max_sdu_size); |
| 269 | /* Note : irttp_run_rx_queue() calculate self->rx_sdu_size |
| 270 | * by summing the size of all fragments, so we should always |
| 271 | * have n == self->rx_sdu_size, except in cases where we |
| 272 | * droped the last fragment (when self->rx_sdu_size exceed |
| 273 | * self->rx_max_sdu_size), where n < self->rx_sdu_size. |
| 274 | * Jean II */ |
| 275 | IRDA_ASSERT(n <= self->rx_sdu_size, n = self->rx_sdu_size;); |
| 276 | |
| 277 | /* Set the new length */ |
| 278 | skb_trim(skb, n); |
| 279 | |
| 280 | self->rx_sdu_size = 0; |
| 281 | |
| 282 | return skb; |
| 283 | } |
| 284 | |
| 285 | /* |
| 286 | * Function irttp_fragment_skb (skb) |
| 287 | * |
| 288 | * Fragments a frame and queues all the fragments for transmission |
| 289 | * |
| 290 | */ |
| 291 | static inline void irttp_fragment_skb(struct tsap_cb *self, |
| 292 | struct sk_buff *skb) |
| 293 | { |
| 294 | struct sk_buff *frag; |
| 295 | __u8 *frame; |
| 296 | |
| 297 | IRDA_ASSERT(self != NULL, return;); |
| 298 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 299 | IRDA_ASSERT(skb != NULL, return;); |
| 300 | |
| 301 | /* |
| 302 | * Split frame into a number of segments |
| 303 | */ |
| 304 | while (skb->len > self->max_seg_size) { |
| 305 | pr_debug("%s(), fragmenting ...\n", __func__); |
| 306 | |
| 307 | /* Make new segment */ |
| 308 | frag = alloc_skb(self->max_seg_size+self->max_header_size, |
| 309 | GFP_ATOMIC); |
| 310 | if (!frag) |
| 311 | return; |
| 312 | |
| 313 | skb_reserve(frag, self->max_header_size); |
| 314 | |
| 315 | /* Copy data from the original skb into this fragment. */ |
| 316 | skb_copy_from_linear_data(skb, skb_put(frag, self->max_seg_size), |
| 317 | self->max_seg_size); |
| 318 | |
| 319 | /* Insert TTP header, with the more bit set */ |
| 320 | frame = skb_push(frag, TTP_HEADER); |
| 321 | frame[0] = TTP_MORE; |
| 322 | |
| 323 | /* Hide the copied data from the original skb */ |
| 324 | skb_pull(skb, self->max_seg_size); |
| 325 | |
| 326 | /* Queue fragment */ |
| 327 | skb_queue_tail(&self->tx_queue, frag); |
| 328 | } |
| 329 | /* Queue what is left of the original skb */ |
| 330 | pr_debug("%s(), queuing last segment\n", __func__); |
| 331 | |
| 332 | frame = skb_push(skb, TTP_HEADER); |
| 333 | frame[0] = 0x00; /* Clear more bit */ |
| 334 | |
| 335 | /* Queue fragment */ |
| 336 | skb_queue_tail(&self->tx_queue, skb); |
| 337 | } |
| 338 | |
| 339 | /* |
| 340 | * Function irttp_param_max_sdu_size (self, param) |
| 341 | * |
| 342 | * Handle the MaxSduSize parameter in the connect frames, this function |
| 343 | * will be called both when this parameter needs to be inserted into, and |
| 344 | * extracted from the connect frames |
| 345 | */ |
| 346 | static int irttp_param_max_sdu_size(void *instance, irda_param_t *param, |
| 347 | int get) |
| 348 | { |
| 349 | struct tsap_cb *self; |
| 350 | |
| 351 | self = instance; |
| 352 | |
| 353 | IRDA_ASSERT(self != NULL, return -1;); |
| 354 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;); |
| 355 | |
| 356 | if (get) |
| 357 | param->pv.i = self->tx_max_sdu_size; |
| 358 | else |
| 359 | self->tx_max_sdu_size = param->pv.i; |
| 360 | |
| 361 | pr_debug("%s(), MaxSduSize=%d\n", __func__, param->pv.i); |
| 362 | |
| 363 | return 0; |
| 364 | } |
| 365 | |
| 366 | /*************************** CLIENT CALLS ***************************/ |
| 367 | /************************** LMP CALLBACKS **************************/ |
| 368 | /* Everything is happily mixed up. Waiting for next clean up - Jean II */ |
| 369 | |
| 370 | /* |
| 371 | * Initialization, that has to be done on new tsap |
| 372 | * instance allocation and on duplication |
| 373 | */ |
| 374 | static void irttp_init_tsap(struct tsap_cb *tsap) |
| 375 | { |
| 376 | spin_lock_init(&tsap->lock); |
| 377 | init_timer(&tsap->todo_timer); |
| 378 | |
| 379 | skb_queue_head_init(&tsap->rx_queue); |
| 380 | skb_queue_head_init(&tsap->tx_queue); |
| 381 | skb_queue_head_init(&tsap->rx_fragments); |
| 382 | } |
| 383 | |
| 384 | /* |
| 385 | * Function irttp_open_tsap (stsap, notify) |
| 386 | * |
| 387 | * Create TSAP connection endpoint, |
| 388 | */ |
| 389 | struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify) |
| 390 | { |
| 391 | struct tsap_cb *self; |
| 392 | struct lsap_cb *lsap; |
| 393 | notify_t ttp_notify; |
| 394 | |
| 395 | IRDA_ASSERT(irttp->magic == TTP_MAGIC, return NULL;); |
| 396 | |
| 397 | /* The IrLMP spec (IrLMP 1.1 p10) says that we have the right to |
| 398 | * use only 0x01-0x6F. Of course, we can use LSAP_ANY as well. |
| 399 | * JeanII */ |
| 400 | if ((stsap_sel != LSAP_ANY) && |
| 401 | ((stsap_sel < 0x01) || (stsap_sel >= 0x70))) { |
| 402 | pr_debug("%s(), invalid tsap!\n", __func__); |
| 403 | return NULL; |
| 404 | } |
| 405 | |
| 406 | self = kzalloc(sizeof(struct tsap_cb), GFP_ATOMIC); |
| 407 | if (self == NULL) |
| 408 | return NULL; |
| 409 | |
| 410 | /* Initialize internal objects */ |
| 411 | irttp_init_tsap(self); |
| 412 | |
| 413 | /* Initialise todo timer */ |
| 414 | self->todo_timer.data = (unsigned long) self; |
| 415 | self->todo_timer.function = &irttp_todo_expired; |
| 416 | |
| 417 | /* Initialize callbacks for IrLMP to use */ |
| 418 | irda_notify_init(&ttp_notify); |
| 419 | ttp_notify.connect_confirm = irttp_connect_confirm; |
| 420 | ttp_notify.connect_indication = irttp_connect_indication; |
| 421 | ttp_notify.disconnect_indication = irttp_disconnect_indication; |
| 422 | ttp_notify.data_indication = irttp_data_indication; |
| 423 | ttp_notify.udata_indication = irttp_udata_indication; |
| 424 | ttp_notify.flow_indication = irttp_flow_indication; |
| 425 | if (notify->status_indication != NULL) |
| 426 | ttp_notify.status_indication = irttp_status_indication; |
| 427 | ttp_notify.instance = self; |
| 428 | strncpy(ttp_notify.name, notify->name, NOTIFY_MAX_NAME); |
| 429 | |
| 430 | self->magic = TTP_TSAP_MAGIC; |
| 431 | self->connected = FALSE; |
| 432 | |
| 433 | /* |
| 434 | * Create LSAP at IrLMP layer |
| 435 | */ |
| 436 | lsap = irlmp_open_lsap(stsap_sel, &ttp_notify, 0); |
| 437 | if (lsap == NULL) { |
| 438 | pr_debug("%s: unable to allocate LSAP!!\n", __func__); |
| 439 | __irttp_close_tsap(self); |
| 440 | return NULL; |
| 441 | } |
| 442 | |
| 443 | /* |
| 444 | * If user specified LSAP_ANY as source TSAP selector, then IrLMP |
| 445 | * will replace it with whatever source selector which is free, so |
| 446 | * the stsap_sel we have might not be valid anymore |
| 447 | */ |
| 448 | self->stsap_sel = lsap->slsap_sel; |
| 449 | pr_debug("%s(), stsap_sel=%02x\n", __func__, self->stsap_sel); |
| 450 | |
| 451 | self->notify = *notify; |
| 452 | self->lsap = lsap; |
| 453 | |
| 454 | hashbin_insert(irttp->tsaps, (irda_queue_t *) self, (long) self, NULL); |
| 455 | |
| 456 | if (credit > TTP_RX_MAX_CREDIT) |
| 457 | self->initial_credit = TTP_RX_MAX_CREDIT; |
| 458 | else |
| 459 | self->initial_credit = credit; |
| 460 | |
| 461 | return self; |
| 462 | } |
| 463 | EXPORT_SYMBOL(irttp_open_tsap); |
| 464 | |
| 465 | /* |
| 466 | * Function irttp_close (handle) |
| 467 | * |
| 468 | * Remove an instance of a TSAP. This function should only deal with the |
| 469 | * deallocation of the TSAP, and resetting of the TSAPs values; |
| 470 | * |
| 471 | */ |
| 472 | static void __irttp_close_tsap(struct tsap_cb *self) |
| 473 | { |
| 474 | /* First make sure we're connected. */ |
| 475 | IRDA_ASSERT(self != NULL, return;); |
| 476 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 477 | |
| 478 | irttp_flush_queues(self); |
| 479 | |
| 480 | del_timer(&self->todo_timer); |
| 481 | |
| 482 | /* This one won't be cleaned up if we are disconnect_pend + close_pend |
| 483 | * and we receive a disconnect_indication */ |
| 484 | if (self->disconnect_skb) |
| 485 | dev_kfree_skb(self->disconnect_skb); |
| 486 | |
| 487 | self->connected = FALSE; |
| 488 | self->magic = ~TTP_TSAP_MAGIC; |
| 489 | |
| 490 | kfree(self); |
| 491 | } |
| 492 | |
| 493 | /* |
| 494 | * Function irttp_close (self) |
| 495 | * |
| 496 | * Remove TSAP from list of all TSAPs and then deallocate all resources |
| 497 | * associated with this TSAP |
| 498 | * |
| 499 | * Note : because we *free* the tsap structure, it is the responsibility |
| 500 | * of the caller to make sure we are called only once and to deal with |
| 501 | * possible race conditions. - Jean II |
| 502 | */ |
| 503 | int irttp_close_tsap(struct tsap_cb *self) |
| 504 | { |
| 505 | struct tsap_cb *tsap; |
| 506 | |
| 507 | IRDA_ASSERT(self != NULL, return -1;); |
| 508 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;); |
| 509 | |
| 510 | /* Make sure tsap has been disconnected */ |
| 511 | if (self->connected) { |
| 512 | /* Check if disconnect is not pending */ |
| 513 | if (!test_bit(0, &self->disconnect_pend)) { |
| 514 | net_warn_ratelimited("%s: TSAP still connected!\n", |
| 515 | __func__); |
| 516 | irttp_disconnect_request(self, NULL, P_NORMAL); |
| 517 | } |
| 518 | self->close_pend = TRUE; |
| 519 | irttp_start_todo_timer(self, HZ/10); |
| 520 | |
| 521 | return 0; /* Will be back! */ |
| 522 | } |
| 523 | |
| 524 | tsap = hashbin_remove(irttp->tsaps, (long) self, NULL); |
| 525 | |
| 526 | IRDA_ASSERT(tsap == self, return -1;); |
| 527 | |
| 528 | /* Close corresponding LSAP */ |
| 529 | if (self->lsap) { |
| 530 | irlmp_close_lsap(self->lsap); |
| 531 | self->lsap = NULL; |
| 532 | } |
| 533 | |
| 534 | __irttp_close_tsap(self); |
| 535 | |
| 536 | return 0; |
| 537 | } |
| 538 | EXPORT_SYMBOL(irttp_close_tsap); |
| 539 | |
| 540 | /* |
| 541 | * Function irttp_udata_request (self, skb) |
| 542 | * |
| 543 | * Send unreliable data on this TSAP |
| 544 | * |
| 545 | */ |
| 546 | int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb) |
| 547 | { |
| 548 | int ret; |
| 549 | |
| 550 | IRDA_ASSERT(self != NULL, return -1;); |
| 551 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;); |
| 552 | IRDA_ASSERT(skb != NULL, return -1;); |
| 553 | |
| 554 | /* Take shortcut on zero byte packets */ |
| 555 | if (skb->len == 0) { |
| 556 | ret = 0; |
| 557 | goto err; |
| 558 | } |
| 559 | |
| 560 | /* Check that nothing bad happens */ |
| 561 | if (!self->connected) { |
| 562 | net_warn_ratelimited("%s(), Not connected\n", __func__); |
| 563 | ret = -ENOTCONN; |
| 564 | goto err; |
| 565 | } |
| 566 | |
| 567 | if (skb->len > self->max_seg_size) { |
| 568 | net_err_ratelimited("%s(), UData is too large for IrLAP!\n", |
| 569 | __func__); |
| 570 | ret = -EMSGSIZE; |
| 571 | goto err; |
| 572 | } |
| 573 | |
| 574 | irlmp_udata_request(self->lsap, skb); |
| 575 | self->stats.tx_packets++; |
| 576 | |
| 577 | return 0; |
| 578 | |
| 579 | err: |
| 580 | dev_kfree_skb(skb); |
| 581 | return ret; |
| 582 | } |
| 583 | EXPORT_SYMBOL(irttp_udata_request); |
| 584 | |
| 585 | |
| 586 | /* |
| 587 | * Function irttp_data_request (handle, skb) |
| 588 | * |
| 589 | * Queue frame for transmission. If SAR is enabled, fragement the frame |
| 590 | * and queue the fragments for transmission |
| 591 | */ |
| 592 | int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb) |
| 593 | { |
| 594 | __u8 *frame; |
| 595 | int ret; |
| 596 | |
| 597 | IRDA_ASSERT(self != NULL, return -1;); |
| 598 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;); |
| 599 | IRDA_ASSERT(skb != NULL, return -1;); |
| 600 | |
| 601 | pr_debug("%s() : queue len = %d\n", __func__, |
| 602 | skb_queue_len(&self->tx_queue)); |
| 603 | |
| 604 | /* Take shortcut on zero byte packets */ |
| 605 | if (skb->len == 0) { |
| 606 | ret = 0; |
| 607 | goto err; |
| 608 | } |
| 609 | |
| 610 | /* Check that nothing bad happens */ |
| 611 | if (!self->connected) { |
| 612 | net_warn_ratelimited("%s: Not connected\n", __func__); |
| 613 | ret = -ENOTCONN; |
| 614 | goto err; |
| 615 | } |
| 616 | |
| 617 | /* |
| 618 | * Check if SAR is disabled, and the frame is larger than what fits |
| 619 | * inside an IrLAP frame |
| 620 | */ |
| 621 | if ((self->tx_max_sdu_size == 0) && (skb->len > self->max_seg_size)) { |
| 622 | net_err_ratelimited("%s: SAR disabled, and data is too large for IrLAP!\n", |
| 623 | __func__); |
| 624 | ret = -EMSGSIZE; |
| 625 | goto err; |
| 626 | } |
| 627 | |
| 628 | /* |
| 629 | * Check if SAR is enabled, and the frame is larger than the |
| 630 | * TxMaxSduSize |
| 631 | */ |
| 632 | if ((self->tx_max_sdu_size != 0) && |
| 633 | (self->tx_max_sdu_size != TTP_SAR_UNBOUND) && |
| 634 | (skb->len > self->tx_max_sdu_size)) { |
| 635 | net_err_ratelimited("%s: SAR enabled, but data is larger than TxMaxSduSize!\n", |
| 636 | __func__); |
| 637 | ret = -EMSGSIZE; |
| 638 | goto err; |
| 639 | } |
| 640 | /* |
| 641 | * Check if transmit queue is full |
| 642 | */ |
| 643 | if (skb_queue_len(&self->tx_queue) >= TTP_TX_MAX_QUEUE) { |
| 644 | /* |
| 645 | * Give it a chance to empty itself |
| 646 | */ |
| 647 | irttp_run_tx_queue(self); |
| 648 | |
| 649 | /* Drop packet. This error code should trigger the caller |
| 650 | * to resend the data in the client code - Jean II */ |
| 651 | ret = -ENOBUFS; |
| 652 | goto err; |
| 653 | } |
| 654 | |
| 655 | /* Queue frame, or queue frame segments */ |
| 656 | if ((self->tx_max_sdu_size == 0) || (skb->len < self->max_seg_size)) { |
| 657 | /* Queue frame */ |
| 658 | IRDA_ASSERT(skb_headroom(skb) >= TTP_HEADER, return -1;); |
| 659 | frame = skb_push(skb, TTP_HEADER); |
| 660 | frame[0] = 0x00; /* Clear more bit */ |
| 661 | |
| 662 | skb_queue_tail(&self->tx_queue, skb); |
| 663 | } else { |
| 664 | /* |
| 665 | * Fragment the frame, this function will also queue the |
| 666 | * fragments, we don't care about the fact the transmit |
| 667 | * queue may be overfilled by all the segments for a little |
| 668 | * while |
| 669 | */ |
| 670 | irttp_fragment_skb(self, skb); |
| 671 | } |
| 672 | |
| 673 | /* Check if we can accept more data from client */ |
| 674 | if ((!self->tx_sdu_busy) && |
| 675 | (skb_queue_len(&self->tx_queue) > TTP_TX_HIGH_THRESHOLD)) { |
| 676 | /* Tx queue filling up, so stop client. */ |
| 677 | if (self->notify.flow_indication) { |
| 678 | self->notify.flow_indication(self->notify.instance, |
| 679 | self, FLOW_STOP); |
| 680 | } |
| 681 | /* self->tx_sdu_busy is the state of the client. |
| 682 | * Update state after notifying client to avoid |
| 683 | * race condition with irttp_flow_indication(). |
| 684 | * If the queue empty itself after our test but before |
| 685 | * we set the flag, we will fix ourselves below in |
| 686 | * irttp_run_tx_queue(). |
| 687 | * Jean II */ |
| 688 | self->tx_sdu_busy = TRUE; |
| 689 | } |
| 690 | |
| 691 | /* Try to make some progress */ |
| 692 | irttp_run_tx_queue(self); |
| 693 | |
| 694 | return 0; |
| 695 | |
| 696 | err: |
| 697 | dev_kfree_skb(skb); |
| 698 | return ret; |
| 699 | } |
| 700 | EXPORT_SYMBOL(irttp_data_request); |
| 701 | |
| 702 | /* |
| 703 | * Function irttp_run_tx_queue (self) |
| 704 | * |
| 705 | * Transmit packets queued for transmission (if possible) |
| 706 | * |
| 707 | */ |
| 708 | static void irttp_run_tx_queue(struct tsap_cb *self) |
| 709 | { |
| 710 | struct sk_buff *skb; |
| 711 | unsigned long flags; |
| 712 | int n; |
| 713 | |
| 714 | pr_debug("%s() : send_credit = %d, queue_len = %d\n", |
| 715 | __func__, |
| 716 | self->send_credit, skb_queue_len(&self->tx_queue)); |
| 717 | |
| 718 | /* Get exclusive access to the tx queue, otherwise don't touch it */ |
| 719 | if (irda_lock(&self->tx_queue_lock) == FALSE) |
| 720 | return; |
| 721 | |
| 722 | /* Try to send out frames as long as we have credits |
| 723 | * and as long as LAP is not full. If LAP is full, it will |
| 724 | * poll us through irttp_flow_indication() - Jean II */ |
| 725 | while ((self->send_credit > 0) && |
| 726 | (!irlmp_lap_tx_queue_full(self->lsap)) && |
| 727 | (skb = skb_dequeue(&self->tx_queue))) { |
| 728 | /* |
| 729 | * Since we can transmit and receive frames concurrently, |
| 730 | * the code below is a critical region and we must assure that |
| 731 | * nobody messes with the credits while we update them. |
| 732 | */ |
| 733 | spin_lock_irqsave(&self->lock, flags); |
| 734 | |
| 735 | n = self->avail_credit; |
| 736 | self->avail_credit = 0; |
| 737 | |
| 738 | /* Only room for 127 credits in frame */ |
| 739 | if (n > 127) { |
| 740 | self->avail_credit = n-127; |
| 741 | n = 127; |
| 742 | } |
| 743 | self->remote_credit += n; |
| 744 | self->send_credit--; |
| 745 | |
| 746 | spin_unlock_irqrestore(&self->lock, flags); |
| 747 | |
| 748 | /* |
| 749 | * More bit must be set by the data_request() or fragment() |
| 750 | * functions |
| 751 | */ |
| 752 | skb->data[0] |= (n & 0x7f); |
| 753 | |
| 754 | /* Detach from socket. |
| 755 | * The current skb has a reference to the socket that sent |
| 756 | * it (skb->sk). When we pass it to IrLMP, the skb will be |
| 757 | * stored in in IrLAP (self->wx_list). When we are within |
| 758 | * IrLAP, we lose the notion of socket, so we should not |
| 759 | * have a reference to a socket. So, we drop it here. |
| 760 | * |
| 761 | * Why does it matter ? |
| 762 | * When the skb is freed (kfree_skb), if it is associated |
| 763 | * with a socket, it release buffer space on the socket |
| 764 | * (through sock_wfree() and sock_def_write_space()). |
| 765 | * If the socket no longer exist, we may crash. Hard. |
| 766 | * When we close a socket, we make sure that associated packets |
| 767 | * in IrTTP are freed. However, we have no way to cancel |
| 768 | * the packet that we have passed to IrLAP. So, if a packet |
| 769 | * remains in IrLAP (retry on the link or else) after we |
| 770 | * close the socket, we are dead ! |
| 771 | * Jean II */ |
| 772 | if (skb->sk != NULL) { |
| 773 | /* IrSOCK application, IrOBEX, ... */ |
| 774 | skb_orphan(skb); |
| 775 | } |
| 776 | /* IrCOMM over IrTTP, IrLAN, ... */ |
| 777 | |
| 778 | /* Pass the skb to IrLMP - done */ |
| 779 | irlmp_data_request(self->lsap, skb); |
| 780 | self->stats.tx_packets++; |
| 781 | } |
| 782 | |
| 783 | /* Check if we can accept more frames from client. |
| 784 | * We don't want to wait until the todo timer to do that, and we |
| 785 | * can't use tasklets (grr...), so we are obliged to give control |
| 786 | * to client. That's ok, this test will be true not too often |
| 787 | * (max once per LAP window) and we are called from places |
| 788 | * where we can spend a bit of time doing stuff. - Jean II */ |
| 789 | if ((self->tx_sdu_busy) && |
| 790 | (skb_queue_len(&self->tx_queue) < TTP_TX_LOW_THRESHOLD) && |
| 791 | (!self->close_pend)) { |
| 792 | if (self->notify.flow_indication) |
| 793 | self->notify.flow_indication(self->notify.instance, |
| 794 | self, FLOW_START); |
| 795 | |
| 796 | /* self->tx_sdu_busy is the state of the client. |
| 797 | * We don't really have a race here, but it's always safer |
| 798 | * to update our state after the client - Jean II */ |
| 799 | self->tx_sdu_busy = FALSE; |
| 800 | } |
| 801 | |
| 802 | /* Reset lock */ |
| 803 | self->tx_queue_lock = 0; |
| 804 | } |
| 805 | |
| 806 | /* |
| 807 | * Function irttp_give_credit (self) |
| 808 | * |
| 809 | * Send a dataless flowdata TTP-PDU and give available credit to peer |
| 810 | * TSAP |
| 811 | */ |
| 812 | static inline void irttp_give_credit(struct tsap_cb *self) |
| 813 | { |
| 814 | struct sk_buff *tx_skb = NULL; |
| 815 | unsigned long flags; |
| 816 | int n; |
| 817 | |
| 818 | IRDA_ASSERT(self != NULL, return;); |
| 819 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 820 | |
| 821 | pr_debug("%s() send=%d,avail=%d,remote=%d\n", |
| 822 | __func__, |
| 823 | self->send_credit, self->avail_credit, self->remote_credit); |
| 824 | |
| 825 | /* Give credit to peer */ |
| 826 | tx_skb = alloc_skb(TTP_MAX_HEADER, GFP_ATOMIC); |
| 827 | if (!tx_skb) |
| 828 | return; |
| 829 | |
| 830 | /* Reserve space for LMP, and LAP header */ |
| 831 | skb_reserve(tx_skb, LMP_MAX_HEADER); |
| 832 | |
| 833 | /* |
| 834 | * Since we can transmit and receive frames concurrently, |
| 835 | * the code below is a critical region and we must assure that |
| 836 | * nobody messes with the credits while we update them. |
| 837 | */ |
| 838 | spin_lock_irqsave(&self->lock, flags); |
| 839 | |
| 840 | n = self->avail_credit; |
| 841 | self->avail_credit = 0; |
| 842 | |
| 843 | /* Only space for 127 credits in frame */ |
| 844 | if (n > 127) { |
| 845 | self->avail_credit = n - 127; |
| 846 | n = 127; |
| 847 | } |
| 848 | self->remote_credit += n; |
| 849 | |
| 850 | spin_unlock_irqrestore(&self->lock, flags); |
| 851 | |
| 852 | skb_put(tx_skb, 1); |
| 853 | tx_skb->data[0] = (__u8) (n & 0x7f); |
| 854 | |
| 855 | irlmp_data_request(self->lsap, tx_skb); |
| 856 | self->stats.tx_packets++; |
| 857 | } |
| 858 | |
| 859 | /* |
| 860 | * Function irttp_udata_indication (instance, sap, skb) |
| 861 | * |
| 862 | * Received some unit-data (unreliable) |
| 863 | * |
| 864 | */ |
| 865 | static int irttp_udata_indication(void *instance, void *sap, |
| 866 | struct sk_buff *skb) |
| 867 | { |
| 868 | struct tsap_cb *self; |
| 869 | int err; |
| 870 | |
| 871 | self = instance; |
| 872 | |
| 873 | IRDA_ASSERT(self != NULL, return -1;); |
| 874 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;); |
| 875 | IRDA_ASSERT(skb != NULL, return -1;); |
| 876 | |
| 877 | self->stats.rx_packets++; |
| 878 | |
| 879 | /* Just pass data to layer above */ |
| 880 | if (self->notify.udata_indication) { |
| 881 | err = self->notify.udata_indication(self->notify.instance, |
| 882 | self, skb); |
| 883 | /* Same comment as in irttp_do_data_indication() */ |
| 884 | if (!err) |
| 885 | return 0; |
| 886 | } |
| 887 | /* Either no handler, or handler returns an error */ |
| 888 | dev_kfree_skb(skb); |
| 889 | |
| 890 | return 0; |
| 891 | } |
| 892 | |
| 893 | /* |
| 894 | * Function irttp_data_indication (instance, sap, skb) |
| 895 | * |
| 896 | * Receive segment from IrLMP. |
| 897 | * |
| 898 | */ |
| 899 | static int irttp_data_indication(void *instance, void *sap, |
| 900 | struct sk_buff *skb) |
| 901 | { |
| 902 | struct tsap_cb *self; |
| 903 | unsigned long flags; |
| 904 | int n; |
| 905 | |
| 906 | self = instance; |
| 907 | |
| 908 | n = skb->data[0] & 0x7f; /* Extract the credits */ |
| 909 | |
| 910 | self->stats.rx_packets++; |
| 911 | |
| 912 | /* Deal with inbound credit |
| 913 | * Since we can transmit and receive frames concurrently, |
| 914 | * the code below is a critical region and we must assure that |
| 915 | * nobody messes with the credits while we update them. |
| 916 | */ |
| 917 | spin_lock_irqsave(&self->lock, flags); |
| 918 | self->send_credit += n; |
| 919 | if (skb->len > 1) |
| 920 | self->remote_credit--; |
| 921 | spin_unlock_irqrestore(&self->lock, flags); |
| 922 | |
| 923 | /* |
| 924 | * Data or dataless packet? Dataless frames contains only the |
| 925 | * TTP_HEADER. |
| 926 | */ |
| 927 | if (skb->len > 1) { |
| 928 | /* |
| 929 | * We don't remove the TTP header, since we must preserve the |
| 930 | * more bit, so the defragment routing knows what to do |
| 931 | */ |
| 932 | skb_queue_tail(&self->rx_queue, skb); |
| 933 | } else { |
| 934 | /* Dataless flowdata TTP-PDU */ |
| 935 | dev_kfree_skb(skb); |
| 936 | } |
| 937 | |
| 938 | |
| 939 | /* Push data to the higher layer. |
| 940 | * We do it synchronously because running the todo timer for each |
| 941 | * receive packet would be too much overhead and latency. |
| 942 | * By passing control to the higher layer, we run the risk that |
| 943 | * it may take time or grab a lock. Most often, the higher layer |
| 944 | * will only put packet in a queue. |
| 945 | * Anyway, packets are only dripping through the IrDA, so we can |
| 946 | * have time before the next packet. |
| 947 | * Further, we are run from NET_BH, so the worse that can happen is |
| 948 | * us missing the optimal time to send back the PF bit in LAP. |
| 949 | * Jean II */ |
| 950 | irttp_run_rx_queue(self); |
| 951 | |
| 952 | /* We now give credits to peer in irttp_run_rx_queue(). |
| 953 | * We need to send credit *NOW*, otherwise we are going |
| 954 | * to miss the next Tx window. The todo timer may take |
| 955 | * a while before it's run... - Jean II */ |
| 956 | |
| 957 | /* |
| 958 | * If the peer device has given us some credits and we didn't have |
| 959 | * anyone from before, then we need to shedule the tx queue. |
| 960 | * We need to do that because our Tx have stopped (so we may not |
| 961 | * get any LAP flow indication) and the user may be stopped as |
| 962 | * well. - Jean II |
| 963 | */ |
| 964 | if (self->send_credit == n) { |
| 965 | /* Restart pushing stuff to LAP */ |
| 966 | irttp_run_tx_queue(self); |
| 967 | /* Note : we don't want to schedule the todo timer |
| 968 | * because it has horrible latency. No tasklets |
| 969 | * because the tasklet API is broken. - Jean II */ |
| 970 | } |
| 971 | |
| 972 | return 0; |
| 973 | } |
| 974 | |
| 975 | /* |
| 976 | * Function irttp_status_indication (self, reason) |
| 977 | * |
| 978 | * Status_indication, just pass to the higher layer... |
| 979 | * |
| 980 | */ |
| 981 | static void irttp_status_indication(void *instance, |
| 982 | LINK_STATUS link, LOCK_STATUS lock) |
| 983 | { |
| 984 | struct tsap_cb *self; |
| 985 | |
| 986 | self = instance; |
| 987 | |
| 988 | IRDA_ASSERT(self != NULL, return;); |
| 989 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 990 | |
| 991 | /* Check if client has already closed the TSAP and gone away */ |
| 992 | if (self->close_pend) |
| 993 | return; |
| 994 | |
| 995 | /* |
| 996 | * Inform service user if he has requested it |
| 997 | */ |
| 998 | if (self->notify.status_indication != NULL) |
| 999 | self->notify.status_indication(self->notify.instance, |
| 1000 | link, lock); |
| 1001 | else |
| 1002 | pr_debug("%s(), no handler\n", __func__); |
| 1003 | } |
| 1004 | |
| 1005 | /* |
| 1006 | * Function irttp_flow_indication (self, reason) |
| 1007 | * |
| 1008 | * Flow_indication : IrLAP tells us to send more data. |
| 1009 | * |
| 1010 | */ |
| 1011 | static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow) |
| 1012 | { |
| 1013 | struct tsap_cb *self; |
| 1014 | |
| 1015 | self = instance; |
| 1016 | |
| 1017 | IRDA_ASSERT(self != NULL, return;); |
| 1018 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 1019 | |
| 1020 | pr_debug("%s(instance=%p)\n", __func__, self); |
| 1021 | |
| 1022 | /* We are "polled" directly from LAP, and the LAP want to fill |
| 1023 | * its Tx window. We want to do our best to send it data, so that |
| 1024 | * we maximise the window. On the other hand, we want to limit the |
| 1025 | * amount of work here so that LAP doesn't hang forever waiting |
| 1026 | * for packets. - Jean II */ |
| 1027 | |
| 1028 | /* Try to send some packets. Currently, LAP calls us every time |
| 1029 | * there is one free slot, so we will send only one packet. |
| 1030 | * This allow the scheduler to do its round robin - Jean II */ |
| 1031 | irttp_run_tx_queue(self); |
| 1032 | |
| 1033 | /* Note regarding the interraction with higher layer. |
| 1034 | * irttp_run_tx_queue() may call the client when its queue |
| 1035 | * start to empty, via notify.flow_indication(). Initially. |
| 1036 | * I wanted this to happen in a tasklet, to avoid client |
| 1037 | * grabbing the CPU, but we can't use tasklets safely. And timer |
| 1038 | * is definitely too slow. |
| 1039 | * This will happen only once per LAP window, and usually at |
| 1040 | * the third packet (unless window is smaller). LAP is still |
| 1041 | * doing mtt and sending first packet so it's sort of OK |
| 1042 | * to do that. Jean II */ |
| 1043 | |
| 1044 | /* If we need to send disconnect. try to do it now */ |
| 1045 | if (self->disconnect_pend) |
| 1046 | irttp_start_todo_timer(self, 0); |
| 1047 | } |
| 1048 | |
| 1049 | /* |
| 1050 | * Function irttp_flow_request (self, command) |
| 1051 | * |
| 1052 | * This function could be used by the upper layers to tell IrTTP to stop |
| 1053 | * delivering frames if the receive queues are starting to get full, or |
| 1054 | * to tell IrTTP to start delivering frames again. |
| 1055 | */ |
| 1056 | void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow) |
| 1057 | { |
| 1058 | IRDA_ASSERT(self != NULL, return;); |
| 1059 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 1060 | |
| 1061 | switch (flow) { |
| 1062 | case FLOW_STOP: |
| 1063 | pr_debug("%s(), flow stop\n", __func__); |
| 1064 | self->rx_sdu_busy = TRUE; |
| 1065 | break; |
| 1066 | case FLOW_START: |
| 1067 | pr_debug("%s(), flow start\n", __func__); |
| 1068 | self->rx_sdu_busy = FALSE; |
| 1069 | |
| 1070 | /* Client say he can accept more data, try to free our |
| 1071 | * queues ASAP - Jean II */ |
| 1072 | irttp_run_rx_queue(self); |
| 1073 | |
| 1074 | break; |
| 1075 | default: |
| 1076 | pr_debug("%s(), Unknown flow command!\n", __func__); |
| 1077 | } |
| 1078 | } |
| 1079 | EXPORT_SYMBOL(irttp_flow_request); |
| 1080 | |
| 1081 | /* |
| 1082 | * Function irttp_connect_request (self, dtsap_sel, daddr, qos) |
| 1083 | * |
| 1084 | * Try to connect to remote destination TSAP selector |
| 1085 | * |
| 1086 | */ |
| 1087 | int irttp_connect_request(struct tsap_cb *self, __u8 dtsap_sel, |
| 1088 | __u32 saddr, __u32 daddr, |
| 1089 | struct qos_info *qos, __u32 max_sdu_size, |
| 1090 | struct sk_buff *userdata) |
| 1091 | { |
| 1092 | struct sk_buff *tx_skb; |
| 1093 | __u8 *frame; |
| 1094 | __u8 n; |
| 1095 | |
| 1096 | pr_debug("%s(), max_sdu_size=%d\n", __func__, max_sdu_size); |
| 1097 | |
| 1098 | IRDA_ASSERT(self != NULL, return -EBADR;); |
| 1099 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -EBADR;); |
| 1100 | |
| 1101 | if (self->connected) { |
| 1102 | if (userdata) |
| 1103 | dev_kfree_skb(userdata); |
| 1104 | return -EISCONN; |
| 1105 | } |
| 1106 | |
| 1107 | /* Any userdata supplied? */ |
| 1108 | if (userdata == NULL) { |
| 1109 | tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER, |
| 1110 | GFP_ATOMIC); |
| 1111 | if (!tx_skb) |
| 1112 | return -ENOMEM; |
| 1113 | |
| 1114 | /* Reserve space for MUX_CONTROL and LAP header */ |
| 1115 | skb_reserve(tx_skb, TTP_MAX_HEADER + TTP_SAR_HEADER); |
| 1116 | } else { |
| 1117 | tx_skb = userdata; |
| 1118 | /* |
| 1119 | * Check that the client has reserved enough space for |
| 1120 | * headers |
| 1121 | */ |
| 1122 | IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER, |
| 1123 | { dev_kfree_skb(userdata); return -1; }); |
| 1124 | } |
| 1125 | |
| 1126 | /* Initialize connection parameters */ |
| 1127 | self->connected = FALSE; |
| 1128 | self->avail_credit = 0; |
| 1129 | self->rx_max_sdu_size = max_sdu_size; |
| 1130 | self->rx_sdu_size = 0; |
| 1131 | self->rx_sdu_busy = FALSE; |
| 1132 | self->dtsap_sel = dtsap_sel; |
| 1133 | |
| 1134 | n = self->initial_credit; |
| 1135 | |
| 1136 | self->remote_credit = 0; |
| 1137 | self->send_credit = 0; |
| 1138 | |
| 1139 | /* |
| 1140 | * Give away max 127 credits for now |
| 1141 | */ |
| 1142 | if (n > 127) { |
| 1143 | self->avail_credit = n - 127; |
| 1144 | n = 127; |
| 1145 | } |
| 1146 | |
| 1147 | self->remote_credit = n; |
| 1148 | |
| 1149 | /* SAR enabled? */ |
| 1150 | if (max_sdu_size > 0) { |
| 1151 | IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER), |
| 1152 | { dev_kfree_skb(tx_skb); return -1; }); |
| 1153 | |
| 1154 | /* Insert SAR parameters */ |
| 1155 | frame = skb_push(tx_skb, TTP_HEADER + TTP_SAR_HEADER); |
| 1156 | |
| 1157 | frame[0] = TTP_PARAMETERS | n; |
| 1158 | frame[1] = 0x04; /* Length */ |
| 1159 | frame[2] = 0x01; /* MaxSduSize */ |
| 1160 | frame[3] = 0x02; /* Value length */ |
| 1161 | |
| 1162 | put_unaligned(cpu_to_be16((__u16) max_sdu_size), |
| 1163 | (__be16 *)(frame+4)); |
| 1164 | } else { |
| 1165 | /* Insert plain TTP header */ |
| 1166 | frame = skb_push(tx_skb, TTP_HEADER); |
| 1167 | |
| 1168 | /* Insert initial credit in frame */ |
| 1169 | frame[0] = n & 0x7f; |
| 1170 | } |
| 1171 | |
| 1172 | /* Connect with IrLMP. No QoS parameters for now */ |
| 1173 | return irlmp_connect_request(self->lsap, dtsap_sel, saddr, daddr, qos, |
| 1174 | tx_skb); |
| 1175 | } |
| 1176 | EXPORT_SYMBOL(irttp_connect_request); |
| 1177 | |
| 1178 | /* |
| 1179 | * Function irttp_connect_confirm (handle, qos, skb) |
| 1180 | * |
| 1181 | * Service user confirms TSAP connection with peer. |
| 1182 | * |
| 1183 | */ |
| 1184 | static void irttp_connect_confirm(void *instance, void *sap, |
| 1185 | struct qos_info *qos, __u32 max_seg_size, |
| 1186 | __u8 max_header_size, struct sk_buff *skb) |
| 1187 | { |
| 1188 | struct tsap_cb *self; |
| 1189 | int parameters; |
| 1190 | int ret; |
| 1191 | __u8 plen; |
| 1192 | __u8 n; |
| 1193 | |
| 1194 | self = instance; |
| 1195 | |
| 1196 | IRDA_ASSERT(self != NULL, return;); |
| 1197 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 1198 | IRDA_ASSERT(skb != NULL, return;); |
| 1199 | |
| 1200 | self->max_seg_size = max_seg_size - TTP_HEADER; |
| 1201 | self->max_header_size = max_header_size + TTP_HEADER; |
| 1202 | |
| 1203 | /* |
| 1204 | * Check if we have got some QoS parameters back! This should be the |
| 1205 | * negotiated QoS for the link. |
| 1206 | */ |
| 1207 | if (qos) { |
| 1208 | pr_debug("IrTTP, Negotiated BAUD_RATE: %02x\n", |
| 1209 | qos->baud_rate.bits); |
| 1210 | pr_debug("IrTTP, Negotiated BAUD_RATE: %d bps.\n", |
| 1211 | qos->baud_rate.value); |
| 1212 | } |
| 1213 | |
| 1214 | n = skb->data[0] & 0x7f; |
| 1215 | |
| 1216 | pr_debug("%s(), Initial send_credit=%d\n", __func__, n); |
| 1217 | |
| 1218 | self->send_credit = n; |
| 1219 | self->tx_max_sdu_size = 0; |
| 1220 | self->connected = TRUE; |
| 1221 | |
| 1222 | parameters = skb->data[0] & 0x80; |
| 1223 | |
| 1224 | IRDA_ASSERT(skb->len >= TTP_HEADER, return;); |
| 1225 | skb_pull(skb, TTP_HEADER); |
| 1226 | |
| 1227 | if (parameters) { |
| 1228 | plen = skb->data[0]; |
| 1229 | |
| 1230 | ret = irda_param_extract_all(self, skb->data+1, |
| 1231 | IRDA_MIN(skb->len-1, plen), |
| 1232 | ¶m_info); |
| 1233 | |
| 1234 | /* Any errors in the parameter list? */ |
| 1235 | if (ret < 0) { |
| 1236 | net_warn_ratelimited("%s: error extracting parameters\n", |
| 1237 | __func__); |
| 1238 | dev_kfree_skb(skb); |
| 1239 | |
| 1240 | /* Do not accept this connection attempt */ |
| 1241 | return; |
| 1242 | } |
| 1243 | /* Remove parameters */ |
| 1244 | skb_pull(skb, IRDA_MIN(skb->len, plen+1)); |
| 1245 | } |
| 1246 | |
| 1247 | pr_debug("%s() send=%d,avail=%d,remote=%d\n", __func__, |
| 1248 | self->send_credit, self->avail_credit, self->remote_credit); |
| 1249 | |
| 1250 | pr_debug("%s(), MaxSduSize=%d\n", __func__, |
| 1251 | self->tx_max_sdu_size); |
| 1252 | |
| 1253 | if (self->notify.connect_confirm) { |
| 1254 | self->notify.connect_confirm(self->notify.instance, self, qos, |
| 1255 | self->tx_max_sdu_size, |
| 1256 | self->max_header_size, skb); |
| 1257 | } else |
| 1258 | dev_kfree_skb(skb); |
| 1259 | } |
| 1260 | |
| 1261 | /* |
| 1262 | * Function irttp_connect_indication (handle, skb) |
| 1263 | * |
| 1264 | * Some other device is connecting to this TSAP |
| 1265 | * |
| 1266 | */ |
| 1267 | static void irttp_connect_indication(void *instance, void *sap, |
| 1268 | struct qos_info *qos, __u32 max_seg_size, __u8 max_header_size, |
| 1269 | struct sk_buff *skb) |
| 1270 | { |
| 1271 | struct tsap_cb *self; |
| 1272 | struct lsap_cb *lsap; |
| 1273 | int parameters; |
| 1274 | int ret; |
| 1275 | __u8 plen; |
| 1276 | __u8 n; |
| 1277 | |
| 1278 | self = instance; |
| 1279 | |
| 1280 | IRDA_ASSERT(self != NULL, return;); |
| 1281 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 1282 | IRDA_ASSERT(skb != NULL, return;); |
| 1283 | |
| 1284 | lsap = sap; |
| 1285 | |
| 1286 | self->max_seg_size = max_seg_size - TTP_HEADER; |
| 1287 | self->max_header_size = max_header_size+TTP_HEADER; |
| 1288 | |
| 1289 | pr_debug("%s(), TSAP sel=%02x\n", __func__, self->stsap_sel); |
| 1290 | |
| 1291 | /* Need to update dtsap_sel if its equal to LSAP_ANY */ |
| 1292 | self->dtsap_sel = lsap->dlsap_sel; |
| 1293 | |
| 1294 | n = skb->data[0] & 0x7f; |
| 1295 | |
| 1296 | self->send_credit = n; |
| 1297 | self->tx_max_sdu_size = 0; |
| 1298 | |
| 1299 | parameters = skb->data[0] & 0x80; |
| 1300 | |
| 1301 | IRDA_ASSERT(skb->len >= TTP_HEADER, return;); |
| 1302 | skb_pull(skb, TTP_HEADER); |
| 1303 | |
| 1304 | if (parameters) { |
| 1305 | plen = skb->data[0]; |
| 1306 | |
| 1307 | ret = irda_param_extract_all(self, skb->data+1, |
| 1308 | IRDA_MIN(skb->len-1, plen), |
| 1309 | ¶m_info); |
| 1310 | |
| 1311 | /* Any errors in the parameter list? */ |
| 1312 | if (ret < 0) { |
| 1313 | net_warn_ratelimited("%s: error extracting parameters\n", |
| 1314 | __func__); |
| 1315 | dev_kfree_skb(skb); |
| 1316 | |
| 1317 | /* Do not accept this connection attempt */ |
| 1318 | return; |
| 1319 | } |
| 1320 | |
| 1321 | /* Remove parameters */ |
| 1322 | skb_pull(skb, IRDA_MIN(skb->len, plen+1)); |
| 1323 | } |
| 1324 | |
| 1325 | if (self->notify.connect_indication) { |
| 1326 | self->notify.connect_indication(self->notify.instance, self, |
| 1327 | qos, self->tx_max_sdu_size, |
| 1328 | self->max_header_size, skb); |
| 1329 | } else |
| 1330 | dev_kfree_skb(skb); |
| 1331 | } |
| 1332 | |
| 1333 | /* |
| 1334 | * Function irttp_connect_response (handle, userdata) |
| 1335 | * |
| 1336 | * Service user is accepting the connection, just pass it down to |
| 1337 | * IrLMP! |
| 1338 | * |
| 1339 | */ |
| 1340 | int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size, |
| 1341 | struct sk_buff *userdata) |
| 1342 | { |
| 1343 | struct sk_buff *tx_skb; |
| 1344 | __u8 *frame; |
| 1345 | int ret; |
| 1346 | __u8 n; |
| 1347 | |
| 1348 | IRDA_ASSERT(self != NULL, return -1;); |
| 1349 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;); |
| 1350 | |
| 1351 | pr_debug("%s(), Source TSAP selector=%02x\n", __func__, |
| 1352 | self->stsap_sel); |
| 1353 | |
| 1354 | /* Any userdata supplied? */ |
| 1355 | if (userdata == NULL) { |
| 1356 | tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER, |
| 1357 | GFP_ATOMIC); |
| 1358 | if (!tx_skb) |
| 1359 | return -ENOMEM; |
| 1360 | |
| 1361 | /* Reserve space for MUX_CONTROL and LAP header */ |
| 1362 | skb_reserve(tx_skb, TTP_MAX_HEADER + TTP_SAR_HEADER); |
| 1363 | } else { |
| 1364 | tx_skb = userdata; |
| 1365 | /* |
| 1366 | * Check that the client has reserved enough space for |
| 1367 | * headers |
| 1368 | */ |
| 1369 | IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER, |
| 1370 | { dev_kfree_skb(userdata); return -1; }); |
| 1371 | } |
| 1372 | |
| 1373 | self->avail_credit = 0; |
| 1374 | self->remote_credit = 0; |
| 1375 | self->rx_max_sdu_size = max_sdu_size; |
| 1376 | self->rx_sdu_size = 0; |
| 1377 | self->rx_sdu_busy = FALSE; |
| 1378 | |
| 1379 | n = self->initial_credit; |
| 1380 | |
| 1381 | /* Frame has only space for max 127 credits (7 bits) */ |
| 1382 | if (n > 127) { |
| 1383 | self->avail_credit = n - 127; |
| 1384 | n = 127; |
| 1385 | } |
| 1386 | |
| 1387 | self->remote_credit = n; |
| 1388 | self->connected = TRUE; |
| 1389 | |
| 1390 | /* SAR enabled? */ |
| 1391 | if (max_sdu_size > 0) { |
| 1392 | IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER), |
| 1393 | { dev_kfree_skb(tx_skb); return -1; }); |
| 1394 | |
| 1395 | /* Insert TTP header with SAR parameters */ |
| 1396 | frame = skb_push(tx_skb, TTP_HEADER + TTP_SAR_HEADER); |
| 1397 | |
| 1398 | frame[0] = TTP_PARAMETERS | n; |
| 1399 | frame[1] = 0x04; /* Length */ |
| 1400 | |
| 1401 | /* irda_param_insert(self, IRTTP_MAX_SDU_SIZE, frame+1, */ |
| 1402 | /* TTP_SAR_HEADER, ¶m_info) */ |
| 1403 | |
| 1404 | frame[2] = 0x01; /* MaxSduSize */ |
| 1405 | frame[3] = 0x02; /* Value length */ |
| 1406 | |
| 1407 | put_unaligned(cpu_to_be16((__u16) max_sdu_size), |
| 1408 | (__be16 *)(frame+4)); |
| 1409 | } else { |
| 1410 | /* Insert TTP header */ |
| 1411 | frame = skb_push(tx_skb, TTP_HEADER); |
| 1412 | |
| 1413 | frame[0] = n & 0x7f; |
| 1414 | } |
| 1415 | |
| 1416 | ret = irlmp_connect_response(self->lsap, tx_skb); |
| 1417 | |
| 1418 | return ret; |
| 1419 | } |
| 1420 | EXPORT_SYMBOL(irttp_connect_response); |
| 1421 | |
| 1422 | /* |
| 1423 | * Function irttp_dup (self, instance) |
| 1424 | * |
| 1425 | * Duplicate TSAP, can be used by servers to confirm a connection on a |
| 1426 | * new TSAP so it can keep listening on the old one. |
| 1427 | */ |
| 1428 | struct tsap_cb *irttp_dup(struct tsap_cb *orig, void *instance) |
| 1429 | { |
| 1430 | struct tsap_cb *new; |
| 1431 | unsigned long flags; |
| 1432 | |
| 1433 | /* Protect our access to the old tsap instance */ |
| 1434 | spin_lock_irqsave(&irttp->tsaps->hb_spinlock, flags); |
| 1435 | |
| 1436 | /* Find the old instance */ |
| 1437 | if (!hashbin_find(irttp->tsaps, (long) orig, NULL)) { |
| 1438 | pr_debug("%s(), unable to find TSAP\n", __func__); |
| 1439 | spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags); |
| 1440 | return NULL; |
| 1441 | } |
| 1442 | |
| 1443 | /* Allocate a new instance */ |
| 1444 | new = kmemdup(orig, sizeof(struct tsap_cb), GFP_ATOMIC); |
| 1445 | if (!new) { |
| 1446 | pr_debug("%s(), unable to kmalloc\n", __func__); |
| 1447 | spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags); |
| 1448 | return NULL; |
| 1449 | } |
| 1450 | spin_lock_init(&new->lock); |
| 1451 | |
| 1452 | /* We don't need the old instance any more */ |
| 1453 | spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags); |
| 1454 | |
| 1455 | /* Try to dup the LSAP (may fail if we were too slow) */ |
| 1456 | new->lsap = irlmp_dup(orig->lsap, new); |
| 1457 | if (!new->lsap) { |
| 1458 | pr_debug("%s(), dup failed!\n", __func__); |
| 1459 | kfree(new); |
| 1460 | return NULL; |
| 1461 | } |
| 1462 | |
| 1463 | /* Not everything should be copied */ |
| 1464 | new->notify.instance = instance; |
| 1465 | |
| 1466 | /* Initialize internal objects */ |
| 1467 | irttp_init_tsap(new); |
| 1468 | |
| 1469 | /* This is locked */ |
| 1470 | hashbin_insert(irttp->tsaps, (irda_queue_t *) new, (long) new, NULL); |
| 1471 | |
| 1472 | return new; |
| 1473 | } |
| 1474 | EXPORT_SYMBOL(irttp_dup); |
| 1475 | |
| 1476 | /* |
| 1477 | * Function irttp_disconnect_request (self) |
| 1478 | * |
| 1479 | * Close this connection please! If priority is high, the queued data |
| 1480 | * segments, if any, will be deallocated first |
| 1481 | * |
| 1482 | */ |
| 1483 | int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *userdata, |
| 1484 | int priority) |
| 1485 | { |
| 1486 | int ret; |
| 1487 | |
| 1488 | IRDA_ASSERT(self != NULL, return -1;); |
| 1489 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;); |
| 1490 | |
| 1491 | /* Already disconnected? */ |
| 1492 | if (!self->connected) { |
| 1493 | pr_debug("%s(), already disconnected!\n", __func__); |
| 1494 | if (userdata) |
| 1495 | dev_kfree_skb(userdata); |
| 1496 | return -1; |
| 1497 | } |
| 1498 | |
| 1499 | /* Disconnect already pending ? |
| 1500 | * We need to use an atomic operation to prevent reentry. This |
| 1501 | * function may be called from various context, like user, timer |
| 1502 | * for following a disconnect_indication() (i.e. net_bh). |
| 1503 | * Jean II */ |
| 1504 | if (test_and_set_bit(0, &self->disconnect_pend)) { |
| 1505 | pr_debug("%s(), disconnect already pending\n", |
| 1506 | __func__); |
| 1507 | if (userdata) |
| 1508 | dev_kfree_skb(userdata); |
| 1509 | |
| 1510 | /* Try to make some progress */ |
| 1511 | irttp_run_tx_queue(self); |
| 1512 | return -1; |
| 1513 | } |
| 1514 | |
| 1515 | /* |
| 1516 | * Check if there is still data segments in the transmit queue |
| 1517 | */ |
| 1518 | if (!skb_queue_empty(&self->tx_queue)) { |
| 1519 | if (priority == P_HIGH) { |
| 1520 | /* |
| 1521 | * No need to send the queued data, if we are |
| 1522 | * disconnecting right now since the data will |
| 1523 | * not have any usable connection to be sent on |
| 1524 | */ |
| 1525 | pr_debug("%s(): High priority!!()\n", __func__); |
| 1526 | irttp_flush_queues(self); |
| 1527 | } else if (priority == P_NORMAL) { |
| 1528 | /* |
| 1529 | * Must delay disconnect until after all data segments |
| 1530 | * have been sent and the tx_queue is empty |
| 1531 | */ |
| 1532 | /* We'll reuse this one later for the disconnect */ |
| 1533 | self->disconnect_skb = userdata; /* May be NULL */ |
| 1534 | |
| 1535 | irttp_run_tx_queue(self); |
| 1536 | |
| 1537 | irttp_start_todo_timer(self, HZ/10); |
| 1538 | return -1; |
| 1539 | } |
| 1540 | } |
| 1541 | /* Note : we don't need to check if self->rx_queue is full and the |
| 1542 | * state of self->rx_sdu_busy because the disconnect response will |
| 1543 | * be sent at the LMP level (so even if the peer has its Tx queue |
| 1544 | * full of data). - Jean II */ |
| 1545 | |
| 1546 | pr_debug("%s(), Disconnecting ...\n", __func__); |
| 1547 | self->connected = FALSE; |
| 1548 | |
| 1549 | if (!userdata) { |
| 1550 | struct sk_buff *tx_skb; |
| 1551 | tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC); |
| 1552 | if (!tx_skb) |
| 1553 | return -ENOMEM; |
| 1554 | |
| 1555 | /* |
| 1556 | * Reserve space for MUX and LAP header |
| 1557 | */ |
| 1558 | skb_reserve(tx_skb, LMP_MAX_HEADER); |
| 1559 | |
| 1560 | userdata = tx_skb; |
| 1561 | } |
| 1562 | ret = irlmp_disconnect_request(self->lsap, userdata); |
| 1563 | |
| 1564 | /* The disconnect is no longer pending */ |
| 1565 | clear_bit(0, &self->disconnect_pend); /* FALSE */ |
| 1566 | |
| 1567 | return ret; |
| 1568 | } |
| 1569 | EXPORT_SYMBOL(irttp_disconnect_request); |
| 1570 | |
| 1571 | /* |
| 1572 | * Function irttp_disconnect_indication (self, reason) |
| 1573 | * |
| 1574 | * Disconnect indication, TSAP disconnected by peer? |
| 1575 | * |
| 1576 | */ |
| 1577 | static void irttp_disconnect_indication(void *instance, void *sap, |
| 1578 | LM_REASON reason, struct sk_buff *skb) |
| 1579 | { |
| 1580 | struct tsap_cb *self; |
| 1581 | |
| 1582 | self = instance; |
| 1583 | |
| 1584 | IRDA_ASSERT(self != NULL, return;); |
| 1585 | IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;); |
| 1586 | |
| 1587 | /* Prevent higher layer to send more data */ |
| 1588 | self->connected = FALSE; |
| 1589 | |
| 1590 | /* Check if client has already tried to close the TSAP */ |
| 1591 | if (self->close_pend) { |
| 1592 | /* In this case, the higher layer is probably gone. Don't |
| 1593 | * bother it and clean up the remains - Jean II */ |
| 1594 | if (skb) |
| 1595 | dev_kfree_skb(skb); |
| 1596 | irttp_close_tsap(self); |
| 1597 | return; |
| 1598 | } |
| 1599 | |
| 1600 | /* If we are here, we assume that is the higher layer is still |
| 1601 | * waiting for the disconnect notification and able to process it, |
| 1602 | * even if he tried to disconnect. Otherwise, it would have already |
| 1603 | * attempted to close the tsap and self->close_pend would be TRUE. |
| 1604 | * Jean II */ |
| 1605 | |
| 1606 | /* No need to notify the client if has already tried to disconnect */ |
| 1607 | if (self->notify.disconnect_indication) |
| 1608 | self->notify.disconnect_indication(self->notify.instance, self, |
| 1609 | reason, skb); |
| 1610 | else |
| 1611 | if (skb) |
| 1612 | dev_kfree_skb(skb); |
| 1613 | } |
| 1614 | |
| 1615 | /* |
| 1616 | * Function irttp_do_data_indication (self, skb) |
| 1617 | * |
| 1618 | * Try to deliver reassembled skb to layer above, and requeue it if that |
| 1619 | * for some reason should fail. We mark rx sdu as busy to apply back |
| 1620 | * pressure is necessary. |
| 1621 | */ |
| 1622 | static void irttp_do_data_indication(struct tsap_cb *self, struct sk_buff *skb) |
| 1623 | { |
| 1624 | int err; |
| 1625 | |
| 1626 | /* Check if client has already closed the TSAP and gone away */ |
| 1627 | if (self->close_pend) { |
| 1628 | dev_kfree_skb(skb); |
| 1629 | return; |
| 1630 | } |
| 1631 | |
| 1632 | err = self->notify.data_indication(self->notify.instance, self, skb); |
| 1633 | |
| 1634 | /* Usually the layer above will notify that it's input queue is |
| 1635 | * starting to get filled by using the flow request, but this may |
| 1636 | * be difficult, so it can instead just refuse to eat it and just |
| 1637 | * give an error back |
| 1638 | */ |
| 1639 | if (err) { |
| 1640 | pr_debug("%s() requeueing skb!\n", __func__); |
| 1641 | |
| 1642 | /* Make sure we take a break */ |
| 1643 | self->rx_sdu_busy = TRUE; |
| 1644 | |
| 1645 | /* Need to push the header in again */ |
| 1646 | skb_push(skb, TTP_HEADER); |
| 1647 | skb->data[0] = 0x00; /* Make sure MORE bit is cleared */ |
| 1648 | |
| 1649 | /* Put skb back on queue */ |
| 1650 | skb_queue_head(&self->rx_queue, skb); |
| 1651 | } |
| 1652 | } |
| 1653 | |
| 1654 | /* |
| 1655 | * Function irttp_run_rx_queue (self) |
| 1656 | * |
| 1657 | * Check if we have any frames to be transmitted, or if we have any |
| 1658 | * available credit to give away. |
| 1659 | */ |
| 1660 | static void irttp_run_rx_queue(struct tsap_cb *self) |
| 1661 | { |
| 1662 | struct sk_buff *skb; |
| 1663 | int more = 0; |
| 1664 | |
| 1665 | pr_debug("%s() send=%d,avail=%d,remote=%d\n", __func__, |
| 1666 | self->send_credit, self->avail_credit, self->remote_credit); |
| 1667 | |
| 1668 | /* Get exclusive access to the rx queue, otherwise don't touch it */ |
| 1669 | if (irda_lock(&self->rx_queue_lock) == FALSE) |
| 1670 | return; |
| 1671 | |
| 1672 | /* |
| 1673 | * Reassemble all frames in receive queue and deliver them |
| 1674 | */ |
| 1675 | while (!self->rx_sdu_busy && (skb = skb_dequeue(&self->rx_queue))) { |
| 1676 | /* This bit will tell us if it's the last fragment or not */ |
| 1677 | more = skb->data[0] & 0x80; |
| 1678 | |
| 1679 | /* Remove TTP header */ |
| 1680 | skb_pull(skb, TTP_HEADER); |
| 1681 | |
| 1682 | /* Add the length of the remaining data */ |
| 1683 | self->rx_sdu_size += skb->len; |
| 1684 | |
| 1685 | /* |
| 1686 | * If SAR is disabled, or user has requested no reassembly |
| 1687 | * of received fragments then we just deliver them |
| 1688 | * immediately. This can be requested by clients that |
| 1689 | * implements byte streams without any message boundaries |
| 1690 | */ |
| 1691 | if (self->rx_max_sdu_size == TTP_SAR_DISABLE) { |
| 1692 | irttp_do_data_indication(self, skb); |
| 1693 | self->rx_sdu_size = 0; |
| 1694 | |
| 1695 | continue; |
| 1696 | } |
| 1697 | |
| 1698 | /* Check if this is a fragment, and not the last fragment */ |
| 1699 | if (more) { |
| 1700 | /* |
| 1701 | * Queue the fragment if we still are within the |
| 1702 | * limits of the maximum size of the rx_sdu |
| 1703 | */ |
| 1704 | if (self->rx_sdu_size <= self->rx_max_sdu_size) { |
| 1705 | pr_debug("%s(), queueing frag\n", |
| 1706 | __func__); |
| 1707 | skb_queue_tail(&self->rx_fragments, skb); |
| 1708 | } else { |
| 1709 | /* Free the part of the SDU that is too big */ |
| 1710 | dev_kfree_skb(skb); |
| 1711 | } |
| 1712 | continue; |
| 1713 | } |
| 1714 | /* |
| 1715 | * This is the last fragment, so time to reassemble! |
| 1716 | */ |
| 1717 | if ((self->rx_sdu_size <= self->rx_max_sdu_size) || |
| 1718 | (self->rx_max_sdu_size == TTP_SAR_UNBOUND)) { |
| 1719 | /* |
| 1720 | * A little optimizing. Only queue the fragment if |
| 1721 | * there are other fragments. Since if this is the |
| 1722 | * last and only fragment, there is no need to |
| 1723 | * reassemble :-) |
| 1724 | */ |
| 1725 | if (!skb_queue_empty(&self->rx_fragments)) { |
| 1726 | skb_queue_tail(&self->rx_fragments, |
| 1727 | skb); |
| 1728 | |
| 1729 | skb = irttp_reassemble_skb(self); |
| 1730 | } |
| 1731 | |
| 1732 | /* Now we can deliver the reassembled skb */ |
| 1733 | irttp_do_data_indication(self, skb); |
| 1734 | } else { |
| 1735 | pr_debug("%s(), Truncated frame\n", __func__); |
| 1736 | |
| 1737 | /* Free the part of the SDU that is too big */ |
| 1738 | dev_kfree_skb(skb); |
| 1739 | |
| 1740 | /* Deliver only the valid but truncated part of SDU */ |
| 1741 | skb = irttp_reassemble_skb(self); |
| 1742 | |
| 1743 | irttp_do_data_indication(self, skb); |
| 1744 | } |
| 1745 | self->rx_sdu_size = 0; |
| 1746 | } |
| 1747 | |
| 1748 | /* |
| 1749 | * It's not trivial to keep track of how many credits are available |
| 1750 | * by incrementing at each packet, because delivery may fail |
| 1751 | * (irttp_do_data_indication() may requeue the frame) and because |
| 1752 | * we need to take care of fragmentation. |
| 1753 | * We want the other side to send up to initial_credit packets. |
| 1754 | * We have some frames in our queues, and we have already allowed it |
| 1755 | * to send remote_credit. |
| 1756 | * No need to spinlock, write is atomic and self correcting... |
| 1757 | * Jean II |
| 1758 | */ |
| 1759 | self->avail_credit = (self->initial_credit - |
| 1760 | (self->remote_credit + |
| 1761 | skb_queue_len(&self->rx_queue) + |
| 1762 | skb_queue_len(&self->rx_fragments))); |
| 1763 | |
| 1764 | /* Do we have too much credits to send to peer ? */ |
| 1765 | if ((self->remote_credit <= TTP_RX_MIN_CREDIT) && |
| 1766 | (self->avail_credit > 0)) { |
| 1767 | /* Send explicit credit frame */ |
| 1768 | irttp_give_credit(self); |
| 1769 | /* Note : do *NOT* check if tx_queue is non-empty, that |
| 1770 | * will produce deadlocks. I repeat : send a credit frame |
| 1771 | * even if we have something to send in our Tx queue. |
| 1772 | * If we have credits, it means that our Tx queue is blocked. |
| 1773 | * |
| 1774 | * Let's suppose the peer can't keep up with our Tx. He will |
| 1775 | * flow control us by not sending us any credits, and we |
| 1776 | * will stop Tx and start accumulating credits here. |
| 1777 | * Up to the point where the peer will stop its Tx queue, |
| 1778 | * for lack of credits. |
| 1779 | * Let's assume the peer application is single threaded. |
| 1780 | * It will block on Tx and never consume any Rx buffer. |
| 1781 | * Deadlock. Guaranteed. - Jean II |
| 1782 | */ |
| 1783 | } |
| 1784 | |
| 1785 | /* Reset lock */ |
| 1786 | self->rx_queue_lock = 0; |
| 1787 | } |
| 1788 | |
| 1789 | #ifdef CONFIG_PROC_FS |
| 1790 | struct irttp_iter_state { |
| 1791 | int id; |
| 1792 | }; |
| 1793 | |
| 1794 | static void *irttp_seq_start(struct seq_file *seq, loff_t *pos) |
| 1795 | { |
| 1796 | struct irttp_iter_state *iter = seq->private; |
| 1797 | struct tsap_cb *self; |
| 1798 | |
| 1799 | /* Protect our access to the tsap list */ |
| 1800 | spin_lock_irq(&irttp->tsaps->hb_spinlock); |
| 1801 | iter->id = 0; |
| 1802 | |
| 1803 | for (self = (struct tsap_cb *) hashbin_get_first(irttp->tsaps); |
| 1804 | self != NULL; |
| 1805 | self = (struct tsap_cb *) hashbin_get_next(irttp->tsaps)) { |
| 1806 | if (iter->id == *pos) |
| 1807 | break; |
| 1808 | ++iter->id; |
| 1809 | } |
| 1810 | |
| 1811 | return self; |
| 1812 | } |
| 1813 | |
| 1814 | static void *irttp_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 1815 | { |
| 1816 | struct irttp_iter_state *iter = seq->private; |
| 1817 | |
| 1818 | ++*pos; |
| 1819 | ++iter->id; |
| 1820 | return (void *) hashbin_get_next(irttp->tsaps); |
| 1821 | } |
| 1822 | |
| 1823 | static void irttp_seq_stop(struct seq_file *seq, void *v) |
| 1824 | { |
| 1825 | spin_unlock_irq(&irttp->tsaps->hb_spinlock); |
| 1826 | } |
| 1827 | |
| 1828 | static int irttp_seq_show(struct seq_file *seq, void *v) |
| 1829 | { |
| 1830 | const struct irttp_iter_state *iter = seq->private; |
| 1831 | const struct tsap_cb *self = v; |
| 1832 | |
| 1833 | seq_printf(seq, "TSAP %d, ", iter->id); |
| 1834 | seq_printf(seq, "stsap_sel: %02x, ", |
| 1835 | self->stsap_sel); |
| 1836 | seq_printf(seq, "dtsap_sel: %02x\n", |
| 1837 | self->dtsap_sel); |
| 1838 | seq_printf(seq, " connected: %s, ", |
| 1839 | self->connected ? "TRUE" : "FALSE"); |
| 1840 | seq_printf(seq, "avail credit: %d, ", |
| 1841 | self->avail_credit); |
| 1842 | seq_printf(seq, "remote credit: %d, ", |
| 1843 | self->remote_credit); |
| 1844 | seq_printf(seq, "send credit: %d\n", |
| 1845 | self->send_credit); |
| 1846 | seq_printf(seq, " tx packets: %lu, ", |
| 1847 | self->stats.tx_packets); |
| 1848 | seq_printf(seq, "rx packets: %lu, ", |
| 1849 | self->stats.rx_packets); |
| 1850 | seq_printf(seq, "tx_queue len: %u ", |
| 1851 | skb_queue_len(&self->tx_queue)); |
| 1852 | seq_printf(seq, "rx_queue len: %u\n", |
| 1853 | skb_queue_len(&self->rx_queue)); |
| 1854 | seq_printf(seq, " tx_sdu_busy: %s, ", |
| 1855 | self->tx_sdu_busy ? "TRUE" : "FALSE"); |
| 1856 | seq_printf(seq, "rx_sdu_busy: %s\n", |
| 1857 | self->rx_sdu_busy ? "TRUE" : "FALSE"); |
| 1858 | seq_printf(seq, " max_seg_size: %u, ", |
| 1859 | self->max_seg_size); |
| 1860 | seq_printf(seq, "tx_max_sdu_size: %u, ", |
| 1861 | self->tx_max_sdu_size); |
| 1862 | seq_printf(seq, "rx_max_sdu_size: %u\n", |
| 1863 | self->rx_max_sdu_size); |
| 1864 | |
| 1865 | seq_printf(seq, " Used by (%s)\n\n", |
| 1866 | self->notify.name); |
| 1867 | return 0; |
| 1868 | } |
| 1869 | |
| 1870 | static const struct seq_operations irttp_seq_ops = { |
| 1871 | .start = irttp_seq_start, |
| 1872 | .next = irttp_seq_next, |
| 1873 | .stop = irttp_seq_stop, |
| 1874 | .show = irttp_seq_show, |
| 1875 | }; |
| 1876 | |
| 1877 | static int irttp_seq_open(struct inode *inode, struct file *file) |
| 1878 | { |
| 1879 | return seq_open_private(file, &irttp_seq_ops, |
| 1880 | sizeof(struct irttp_iter_state)); |
| 1881 | } |
| 1882 | |
| 1883 | const struct file_operations irttp_seq_fops = { |
| 1884 | .owner = THIS_MODULE, |
| 1885 | .open = irttp_seq_open, |
| 1886 | .read = seq_read, |
| 1887 | .llseek = seq_lseek, |
| 1888 | .release = seq_release_private, |
| 1889 | }; |
| 1890 | |
| 1891 | #endif /* PROC_FS */ |