1/* 2 * Ultra Wide Band 3 * Dynamic Reservation Protocol handling 4 * 5 * Copyright (C) 2005-2006 Intel Corporation 6 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> 7 * Copyright (C) 2008 Cambridge Silicon Radio Ltd. 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License version 11 * 2 as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program. If not, see <http://www.gnu.org/licenses/>. 20 */ 21#include <linux/kthread.h> 22#include <linux/freezer.h> 23#include <linux/slab.h> 24#include <linux/delay.h> 25#include "uwb-internal.h" 26 27 28/* DRP Conflict Actions ([ECMA-368 2nd Edition] 17.4.6) */ 29enum uwb_drp_conflict_action { 30 /* Reservation is maintained, no action needed */ 31 UWB_DRP_CONFLICT_MANTAIN = 0, 32 33 /* the device shall not transmit frames in conflicting MASs in 34 * the following superframe. If the device is the reservation 35 * target, it shall also set the Reason Code in its DRP IE to 36 * Conflict in its beacon in the following superframe. 37 */ 38 UWB_DRP_CONFLICT_ACT1, 39 40 /* the device shall not set the Reservation Status bit to ONE 41 * and shall not transmit frames in conflicting MASs. If the 42 * device is the reservation target, it shall also set the 43 * Reason Code in its DRP IE to Conflict. 44 */ 45 UWB_DRP_CONFLICT_ACT2, 46 47 /* the device shall not transmit frames in conflicting MASs in 48 * the following superframe. It shall remove the conflicting 49 * MASs from the reservation or set the Reservation Status to 50 * ZERO in its beacon in the following superframe. If the 51 * device is the reservation target, it shall also set the 52 * Reason Code in its DRP IE to Conflict. 53 */ 54 UWB_DRP_CONFLICT_ACT3, 55}; 56 57 58static void uwb_rc_set_drp_cmd_done(struct uwb_rc *rc, void *arg, 59 struct uwb_rceb *reply, ssize_t reply_size) 60{ 61 struct uwb_rc_evt_set_drp_ie *r = (struct uwb_rc_evt_set_drp_ie *)reply; 62 unsigned long flags; 63 64 if (r != NULL) { 65 if (r->bResultCode != UWB_RC_RES_SUCCESS) 66 dev_err(&rc->uwb_dev.dev, "SET-DRP-IE failed: %s (%d)\n", 67 uwb_rc_strerror(r->bResultCode), r->bResultCode); 68 } else 69 dev_err(&rc->uwb_dev.dev, "SET-DRP-IE: timeout\n"); 70 71 spin_lock_irqsave(&rc->rsvs_lock, flags); 72 if (rc->set_drp_ie_pending > 1) { 73 rc->set_drp_ie_pending = 0; 74 uwb_rsv_queue_update(rc); 75 } else { 76 rc->set_drp_ie_pending = 0; 77 } 78 spin_unlock_irqrestore(&rc->rsvs_lock, flags); 79} 80 81/** 82 * Construct and send the SET DRP IE 83 * 84 * @rc: UWB Host controller 85 * @returns: >= 0 number of bytes still available in the beacon 86 * < 0 errno code on error. 87 * 88 * See WUSB[8.6.2.7]: The host must set all the DRP IEs that it wants the 89 * device to include in its beacon at the same time. We thus have to 90 * traverse all reservations and include the DRP IEs of all PENDING 91 * and NEGOTIATED reservations in a SET DRP command for transmission. 92 * 93 * A DRP Availability IE is appended. 94 * 95 * rc->rsvs_mutex is held 96 * 97 * FIXME We currently ignore the returned value indicating the remaining space 98 * in beacon. This could be used to deny reservation requests earlier if 99 * determined that they would cause the beacon space to be exceeded. 100 */ 101int uwb_rc_send_all_drp_ie(struct uwb_rc *rc) 102{ 103 int result; 104 struct uwb_rc_cmd_set_drp_ie *cmd; 105 struct uwb_rsv *rsv; 106 struct uwb_rsv_move *mv; 107 int num_bytes = 0; 108 u8 *IEDataptr; 109 110 result = -ENOMEM; 111 /* First traverse all reservations to determine memory needed. */ 112 list_for_each_entry(rsv, &rc->reservations, rc_node) { 113 if (rsv->drp_ie != NULL) { 114 num_bytes += rsv->drp_ie->hdr.length + 2; 115 if (uwb_rsv_has_two_drp_ies(rsv) && 116 (rsv->mv.companion_drp_ie != NULL)) { 117 mv = &rsv->mv; 118 num_bytes += 119 mv->companion_drp_ie->hdr.length + 2; 120 } 121 } 122 } 123 num_bytes += sizeof(rc->drp_avail.ie); 124 cmd = kzalloc(sizeof(*cmd) + num_bytes, GFP_KERNEL); 125 if (cmd == NULL) 126 goto error; 127 cmd->rccb.bCommandType = UWB_RC_CET_GENERAL; 128 cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_SET_DRP_IE); 129 cmd->wIELength = num_bytes; 130 IEDataptr = (u8 *)&cmd->IEData[0]; 131 132 /* FIXME: DRV avail IE is not always needed */ 133 /* put DRP avail IE first */ 134 memcpy(IEDataptr, &rc->drp_avail.ie, sizeof(rc->drp_avail.ie)); 135 IEDataptr += sizeof(struct uwb_ie_drp_avail); 136 137 /* Next traverse all reservations to place IEs in allocated memory. */ 138 list_for_each_entry(rsv, &rc->reservations, rc_node) { 139 if (rsv->drp_ie != NULL) { 140 memcpy(IEDataptr, rsv->drp_ie, 141 rsv->drp_ie->hdr.length + 2); 142 IEDataptr += rsv->drp_ie->hdr.length + 2; 143 144 if (uwb_rsv_has_two_drp_ies(rsv) && 145 (rsv->mv.companion_drp_ie != NULL)) { 146 mv = &rsv->mv; 147 memcpy(IEDataptr, mv->companion_drp_ie, 148 mv->companion_drp_ie->hdr.length + 2); 149 IEDataptr += 150 mv->companion_drp_ie->hdr.length + 2; 151 } 152 } 153 } 154 155 result = uwb_rc_cmd_async(rc, "SET-DRP-IE", 156 &cmd->rccb, sizeof(*cmd) + num_bytes, 157 UWB_RC_CET_GENERAL, UWB_RC_CMD_SET_DRP_IE, 158 uwb_rc_set_drp_cmd_done, NULL); 159 160 rc->set_drp_ie_pending = 1; 161 162 kfree(cmd); 163error: 164 return result; 165} 166 167/* 168 * Evaluate the action to perform using conflict resolution rules 169 * 170 * Return a uwb_drp_conflict_action. 171 */ 172static int evaluate_conflict_action(struct uwb_ie_drp *ext_drp_ie, int ext_beacon_slot, 173 struct uwb_rsv *rsv, int our_status) 174{ 175 int our_tie_breaker = rsv->tiebreaker; 176 int our_type = rsv->type; 177 int our_beacon_slot = rsv->rc->uwb_dev.beacon_slot; 178 179 int ext_tie_breaker = uwb_ie_drp_tiebreaker(ext_drp_ie); 180 int ext_status = uwb_ie_drp_status(ext_drp_ie); 181 int ext_type = uwb_ie_drp_type(ext_drp_ie); 182 183 184 /* [ECMA-368 2nd Edition] 17.4.6 */ 185 if (ext_type == UWB_DRP_TYPE_PCA && our_type == UWB_DRP_TYPE_PCA) { 186 return UWB_DRP_CONFLICT_MANTAIN; 187 } 188 189 /* [ECMA-368 2nd Edition] 17.4.6-1 */ 190 if (our_type == UWB_DRP_TYPE_ALIEN_BP) { 191 return UWB_DRP_CONFLICT_MANTAIN; 192 } 193 194 /* [ECMA-368 2nd Edition] 17.4.6-2 */ 195 if (ext_type == UWB_DRP_TYPE_ALIEN_BP) { 196 /* here we know our_type != UWB_DRP_TYPE_ALIEN_BP */ 197 return UWB_DRP_CONFLICT_ACT1; 198 } 199 200 /* [ECMA-368 2nd Edition] 17.4.6-3 */ 201 if (our_status == 0 && ext_status == 1) { 202 return UWB_DRP_CONFLICT_ACT2; 203 } 204 205 /* [ECMA-368 2nd Edition] 17.4.6-4 */ 206 if (our_status == 1 && ext_status == 0) { 207 return UWB_DRP_CONFLICT_MANTAIN; 208 } 209 210 /* [ECMA-368 2nd Edition] 17.4.6-5a */ 211 if (our_tie_breaker == ext_tie_breaker && 212 our_beacon_slot < ext_beacon_slot) { 213 return UWB_DRP_CONFLICT_MANTAIN; 214 } 215 216 /* [ECMA-368 2nd Edition] 17.4.6-5b */ 217 if (our_tie_breaker != ext_tie_breaker && 218 our_beacon_slot > ext_beacon_slot) { 219 return UWB_DRP_CONFLICT_MANTAIN; 220 } 221 222 if (our_status == 0) { 223 if (our_tie_breaker == ext_tie_breaker) { 224 /* [ECMA-368 2nd Edition] 17.4.6-6a */ 225 if (our_beacon_slot > ext_beacon_slot) { 226 return UWB_DRP_CONFLICT_ACT2; 227 } 228 } else { 229 /* [ECMA-368 2nd Edition] 17.4.6-6b */ 230 if (our_beacon_slot < ext_beacon_slot) { 231 return UWB_DRP_CONFLICT_ACT2; 232 } 233 } 234 } else { 235 if (our_tie_breaker == ext_tie_breaker) { 236 /* [ECMA-368 2nd Edition] 17.4.6-7a */ 237 if (our_beacon_slot > ext_beacon_slot) { 238 return UWB_DRP_CONFLICT_ACT3; 239 } 240 } else { 241 /* [ECMA-368 2nd Edition] 17.4.6-7b */ 242 if (our_beacon_slot < ext_beacon_slot) { 243 return UWB_DRP_CONFLICT_ACT3; 244 } 245 } 246 } 247 return UWB_DRP_CONFLICT_MANTAIN; 248} 249 250static void handle_conflict_normal(struct uwb_ie_drp *drp_ie, 251 int ext_beacon_slot, 252 struct uwb_rsv *rsv, 253 struct uwb_mas_bm *conflicting_mas) 254{ 255 struct uwb_rc *rc = rsv->rc; 256 struct uwb_rsv_move *mv = &rsv->mv; 257 struct uwb_drp_backoff_win *bow = &rc->bow; 258 int action; 259 260 action = evaluate_conflict_action(drp_ie, ext_beacon_slot, rsv, uwb_rsv_status(rsv)); 261 262 if (uwb_rsv_is_owner(rsv)) { 263 switch(action) { 264 case UWB_DRP_CONFLICT_ACT2: 265 /* try move */ 266 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_TO_BE_MOVED); 267 if (bow->can_reserve_extra_mases == false) 268 uwb_rsv_backoff_win_increment(rc); 269 270 break; 271 case UWB_DRP_CONFLICT_ACT3: 272 uwb_rsv_backoff_win_increment(rc); 273 /* drop some mases with reason modified */ 274 /* put in the companion the mases to be dropped */ 275 bitmap_and(mv->companion_mas.bm, rsv->mas.bm, conflicting_mas->bm, UWB_NUM_MAS); 276 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MODIFIED); 277 default: 278 break; 279 } 280 } else { 281 switch(action) { 282 case UWB_DRP_CONFLICT_ACT2: 283 case UWB_DRP_CONFLICT_ACT3: 284 uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_CONFLICT); 285 default: 286 break; 287 } 288 289 } 290 291} 292 293static void handle_conflict_expanding(struct uwb_ie_drp *drp_ie, int ext_beacon_slot, 294 struct uwb_rsv *rsv, bool companion_only, 295 struct uwb_mas_bm *conflicting_mas) 296{ 297 struct uwb_rc *rc = rsv->rc; 298 struct uwb_drp_backoff_win *bow = &rc->bow; 299 struct uwb_rsv_move *mv = &rsv->mv; 300 int action; 301 302 if (companion_only) { 303 /* status of companion is 0 at this point */ 304 action = evaluate_conflict_action(drp_ie, ext_beacon_slot, rsv, 0); 305 if (uwb_rsv_is_owner(rsv)) { 306 switch(action) { 307 case UWB_DRP_CONFLICT_ACT2: 308 case UWB_DRP_CONFLICT_ACT3: 309 uwb_rsv_set_state(rsv, 310 UWB_RSV_STATE_O_ESTABLISHED); 311 rsv->needs_release_companion_mas = false; 312 if (bow->can_reserve_extra_mases == false) 313 uwb_rsv_backoff_win_increment(rc); 314 uwb_drp_avail_release(rsv->rc, 315 &rsv->mv.companion_mas); 316 } 317 } else { /* rsv is target */ 318 switch(action) { 319 case UWB_DRP_CONFLICT_ACT2: 320 case UWB_DRP_CONFLICT_ACT3: 321 uwb_rsv_set_state(rsv, 322 UWB_RSV_STATE_T_EXPANDING_CONFLICT); 323 /* send_drp_avail_ie = true; */ 324 } 325 } 326 } else { /* also base part of the reservation is conflicting */ 327 if (uwb_rsv_is_owner(rsv)) { 328 uwb_rsv_backoff_win_increment(rc); 329 /* remove companion part */ 330 uwb_drp_avail_release(rsv->rc, &rsv->mv.companion_mas); 331 332 /* drop some mases with reason modified */ 333 334 /* put in the companion the mases to be dropped */ 335 bitmap_andnot(mv->companion_mas.bm, rsv->mas.bm, 336 conflicting_mas->bm, UWB_NUM_MAS); 337 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MODIFIED); 338 } else { /* it is a target rsv */ 339 uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_CONFLICT); 340 /* send_drp_avail_ie = true; */ 341 } 342 } 343} 344 345static void uwb_drp_handle_conflict_rsv(struct uwb_rc *rc, struct uwb_rsv *rsv, 346 struct uwb_rc_evt_drp *drp_evt, 347 struct uwb_ie_drp *drp_ie, 348 struct uwb_mas_bm *conflicting_mas) 349{ 350 struct uwb_rsv_move *mv; 351 352 /* check if the conflicting reservation has two drp_ies */ 353 if (uwb_rsv_has_two_drp_ies(rsv)) { 354 mv = &rsv->mv; 355 if (bitmap_intersects(rsv->mas.bm, conflicting_mas->bm, 356 UWB_NUM_MAS)) { 357 handle_conflict_expanding(drp_ie, 358 drp_evt->beacon_slot_number, 359 rsv, false, conflicting_mas); 360 } else { 361 if (bitmap_intersects(mv->companion_mas.bm, 362 conflicting_mas->bm, UWB_NUM_MAS)) { 363 handle_conflict_expanding( 364 drp_ie, drp_evt->beacon_slot_number, 365 rsv, true, conflicting_mas); 366 } 367 } 368 } else if (bitmap_intersects(rsv->mas.bm, conflicting_mas->bm, 369 UWB_NUM_MAS)) { 370 handle_conflict_normal(drp_ie, drp_evt->beacon_slot_number, 371 rsv, conflicting_mas); 372 } 373} 374 375static void uwb_drp_handle_all_conflict_rsv(struct uwb_rc *rc, 376 struct uwb_rc_evt_drp *drp_evt, 377 struct uwb_ie_drp *drp_ie, 378 struct uwb_mas_bm *conflicting_mas) 379{ 380 struct uwb_rsv *rsv; 381 382 list_for_each_entry(rsv, &rc->reservations, rc_node) { 383 uwb_drp_handle_conflict_rsv(rc, rsv, drp_evt, drp_ie, 384 conflicting_mas); 385 } 386} 387 388static void uwb_drp_process_target_accepted(struct uwb_rc *rc, 389 struct uwb_rsv *rsv, struct uwb_rc_evt_drp *drp_evt, 390 struct uwb_ie_drp *drp_ie, struct uwb_mas_bm *mas) 391{ 392 struct uwb_rsv_move *mv = &rsv->mv; 393 int status; 394 395 status = uwb_ie_drp_status(drp_ie); 396 397 if (rsv->state == UWB_RSV_STATE_T_CONFLICT) { 398 uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_CONFLICT); 399 return; 400 } 401 402 if (rsv->state == UWB_RSV_STATE_T_EXPANDING_ACCEPTED) { 403 /* drp_ie is companion */ 404 if (!bitmap_equal(rsv->mas.bm, mas->bm, UWB_NUM_MAS)) { 405 /* stroke companion */ 406 uwb_rsv_set_state(rsv, 407 UWB_RSV_STATE_T_EXPANDING_ACCEPTED); 408 } 409 } else { 410 if (!bitmap_equal(rsv->mas.bm, mas->bm, UWB_NUM_MAS)) { 411 if (uwb_drp_avail_reserve_pending(rc, mas) == -EBUSY) { 412 /* FIXME: there is a conflict, find 413 * the conflicting reservations and 414 * take a sensible action. Consider 415 * that in drp_ie there is the 416 * "neighbour" */ 417 uwb_drp_handle_all_conflict_rsv(rc, drp_evt, 418 drp_ie, mas); 419 } else { 420 /* accept the extra reservation */ 421 bitmap_copy(mv->companion_mas.bm, mas->bm, 422 UWB_NUM_MAS); 423 uwb_rsv_set_state(rsv, 424 UWB_RSV_STATE_T_EXPANDING_ACCEPTED); 425 } 426 } else { 427 if (status) { 428 uwb_rsv_set_state(rsv, 429 UWB_RSV_STATE_T_ACCEPTED); 430 } 431 } 432 433 } 434} 435 436/* 437 * Based on the DRP IE, transition a target reservation to a new 438 * state. 439 */ 440static void uwb_drp_process_target(struct uwb_rc *rc, struct uwb_rsv *rsv, 441 struct uwb_ie_drp *drp_ie, struct uwb_rc_evt_drp *drp_evt) 442{ 443 struct device *dev = &rc->uwb_dev.dev; 444 struct uwb_rsv_move *mv = &rsv->mv; 445 int status; 446 enum uwb_drp_reason reason_code; 447 struct uwb_mas_bm mas; 448 449 status = uwb_ie_drp_status(drp_ie); 450 reason_code = uwb_ie_drp_reason_code(drp_ie); 451 uwb_drp_ie_to_bm(&mas, drp_ie); 452 453 switch (reason_code) { 454 case UWB_DRP_REASON_ACCEPTED: 455 uwb_drp_process_target_accepted(rc, rsv, drp_evt, drp_ie, &mas); 456 break; 457 458 case UWB_DRP_REASON_MODIFIED: 459 /* check to see if we have already modified the reservation */ 460 if (bitmap_equal(rsv->mas.bm, mas.bm, UWB_NUM_MAS)) { 461 uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_ACCEPTED); 462 break; 463 } 464 465 /* find if the owner wants to expand or reduce */ 466 if (bitmap_subset(mas.bm, rsv->mas.bm, UWB_NUM_MAS)) { 467 /* owner is reducing */ 468 bitmap_andnot(mv->companion_mas.bm, rsv->mas.bm, mas.bm, 469 UWB_NUM_MAS); 470 uwb_drp_avail_release(rsv->rc, &mv->companion_mas); 471 } 472 473 bitmap_copy(rsv->mas.bm, mas.bm, UWB_NUM_MAS); 474 uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_RESIZED); 475 break; 476 default: 477 dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", 478 reason_code, status); 479 } 480} 481 482static void uwb_drp_process_owner_accepted(struct uwb_rsv *rsv, 483 struct uwb_mas_bm *mas) 484{ 485 struct uwb_rsv_move *mv = &rsv->mv; 486 487 switch (rsv->state) { 488 case UWB_RSV_STATE_O_PENDING: 489 case UWB_RSV_STATE_O_INITIATED: 490 case UWB_RSV_STATE_O_ESTABLISHED: 491 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); 492 break; 493 case UWB_RSV_STATE_O_MODIFIED: 494 if (bitmap_equal(mas->bm, rsv->mas.bm, UWB_NUM_MAS)) 495 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); 496 else 497 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MODIFIED); 498 break; 499 500 case UWB_RSV_STATE_O_MOVE_REDUCING: /* shouldn' t be a problem */ 501 if (bitmap_equal(mas->bm, rsv->mas.bm, UWB_NUM_MAS)) 502 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); 503 else 504 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_REDUCING); 505 break; 506 case UWB_RSV_STATE_O_MOVE_EXPANDING: 507 if (bitmap_equal(mas->bm, mv->companion_mas.bm, UWB_NUM_MAS)) { 508 /* Companion reservation accepted */ 509 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_COMBINING); 510 } else { 511 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_EXPANDING); 512 } 513 break; 514 case UWB_RSV_STATE_O_MOVE_COMBINING: 515 if (bitmap_equal(mas->bm, rsv->mas.bm, UWB_NUM_MAS)) 516 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_REDUCING); 517 else 518 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_COMBINING); 519 break; 520 default: 521 break; 522 } 523} 524/* 525 * Based on the DRP IE, transition an owner reservation to a new 526 * state. 527 */ 528static void uwb_drp_process_owner(struct uwb_rc *rc, struct uwb_rsv *rsv, 529 struct uwb_dev *src, struct uwb_ie_drp *drp_ie, 530 struct uwb_rc_evt_drp *drp_evt) 531{ 532 struct device *dev = &rc->uwb_dev.dev; 533 int status; 534 enum uwb_drp_reason reason_code; 535 struct uwb_mas_bm mas; 536 537 status = uwb_ie_drp_status(drp_ie); 538 reason_code = uwb_ie_drp_reason_code(drp_ie); 539 uwb_drp_ie_to_bm(&mas, drp_ie); 540 541 if (status) { 542 switch (reason_code) { 543 case UWB_DRP_REASON_ACCEPTED: 544 uwb_drp_process_owner_accepted(rsv, &mas); 545 break; 546 default: 547 dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", 548 reason_code, status); 549 } 550 } else { 551 switch (reason_code) { 552 case UWB_DRP_REASON_PENDING: 553 uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_PENDING); 554 break; 555 case UWB_DRP_REASON_DENIED: 556 uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); 557 break; 558 case UWB_DRP_REASON_CONFLICT: 559 /* resolve the conflict */ 560 bitmap_complement(mas.bm, src->last_availability_bm, 561 UWB_NUM_MAS); 562 uwb_drp_handle_conflict_rsv(rc, rsv, drp_evt, drp_ie, &mas); 563 break; 564 default: 565 dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", 566 reason_code, status); 567 } 568 } 569} 570 571static void uwb_cnflt_alien_stroke_timer(struct uwb_cnflt_alien *cnflt) 572{ 573 unsigned timeout_us = UWB_MAX_LOST_BEACONS * UWB_SUPERFRAME_LENGTH_US; 574 mod_timer(&cnflt->timer, jiffies + usecs_to_jiffies(timeout_us)); 575} 576 577static void uwb_cnflt_update_work(struct work_struct *work) 578{ 579 struct uwb_cnflt_alien *cnflt = container_of(work, 580 struct uwb_cnflt_alien, 581 cnflt_update_work); 582 struct uwb_cnflt_alien *c; 583 struct uwb_rc *rc = cnflt->rc; 584 585 unsigned long delay_us = UWB_MAS_LENGTH_US * UWB_MAS_PER_ZONE; 586 587 mutex_lock(&rc->rsvs_mutex); 588 589 list_del(&cnflt->rc_node); 590 591 /* update rc global conflicting alien bitmap */ 592 bitmap_zero(rc->cnflt_alien_bitmap.bm, UWB_NUM_MAS); 593 594 list_for_each_entry(c, &rc->cnflt_alien_list, rc_node) { 595 bitmap_or(rc->cnflt_alien_bitmap.bm, rc->cnflt_alien_bitmap.bm, 596 c->mas.bm, UWB_NUM_MAS); 597 } 598 599 queue_delayed_work(rc->rsv_workq, &rc->rsv_alien_bp_work, 600 usecs_to_jiffies(delay_us)); 601 602 kfree(cnflt); 603 mutex_unlock(&rc->rsvs_mutex); 604} 605 606static void uwb_cnflt_timer(unsigned long arg) 607{ 608 struct uwb_cnflt_alien *cnflt = (struct uwb_cnflt_alien *)arg; 609 610 queue_work(cnflt->rc->rsv_workq, &cnflt->cnflt_update_work); 611} 612 613/* 614 * We have received an DRP_IE of type Alien BP and we need to make 615 * sure we do not transmit in conflicting MASs. 616 */ 617static void uwb_drp_handle_alien_drp(struct uwb_rc *rc, struct uwb_ie_drp *drp_ie) 618{ 619 struct device *dev = &rc->uwb_dev.dev; 620 struct uwb_mas_bm mas; 621 struct uwb_cnflt_alien *cnflt; 622 char buf[72]; 623 unsigned long delay_us = UWB_MAS_LENGTH_US * UWB_MAS_PER_ZONE; 624 625 uwb_drp_ie_to_bm(&mas, drp_ie); 626 bitmap_scnprintf(buf, sizeof(buf), mas.bm, UWB_NUM_MAS); 627 628 list_for_each_entry(cnflt, &rc->cnflt_alien_list, rc_node) { 629 if (bitmap_equal(cnflt->mas.bm, mas.bm, UWB_NUM_MAS)) { 630 /* Existing alien BP reservation conflicting 631 * bitmap, just reset the timer */ 632 uwb_cnflt_alien_stroke_timer(cnflt); 633 return; 634 } 635 } 636 637 /* New alien BP reservation conflicting bitmap */ 638 639 /* alloc and initialize new uwb_cnflt_alien */ 640 cnflt = kzalloc(sizeof(struct uwb_cnflt_alien), GFP_KERNEL); 641 if (!cnflt) { 642 dev_err(dev, "failed to alloc uwb_cnflt_alien struct\n"); 643 return; 644 } 645 646 INIT_LIST_HEAD(&cnflt->rc_node); 647 init_timer(&cnflt->timer); 648 cnflt->timer.function = uwb_cnflt_timer; 649 cnflt->timer.data = (unsigned long)cnflt; 650 651 cnflt->rc = rc; 652 INIT_WORK(&cnflt->cnflt_update_work, uwb_cnflt_update_work); 653 654 bitmap_copy(cnflt->mas.bm, mas.bm, UWB_NUM_MAS); 655 656 list_add_tail(&cnflt->rc_node, &rc->cnflt_alien_list); 657 658 /* update rc global conflicting alien bitmap */ 659 bitmap_or(rc->cnflt_alien_bitmap.bm, rc->cnflt_alien_bitmap.bm, mas.bm, UWB_NUM_MAS); 660 661 queue_delayed_work(rc->rsv_workq, &rc->rsv_alien_bp_work, usecs_to_jiffies(delay_us)); 662 663 /* start the timer */ 664 uwb_cnflt_alien_stroke_timer(cnflt); 665} 666 667static void uwb_drp_process_not_involved(struct uwb_rc *rc, 668 struct uwb_rc_evt_drp *drp_evt, 669 struct uwb_ie_drp *drp_ie) 670{ 671 struct uwb_mas_bm mas; 672 673 uwb_drp_ie_to_bm(&mas, drp_ie); 674 uwb_drp_handle_all_conflict_rsv(rc, drp_evt, drp_ie, &mas); 675} 676 677static void uwb_drp_process_involved(struct uwb_rc *rc, struct uwb_dev *src, 678 struct uwb_rc_evt_drp *drp_evt, 679 struct uwb_ie_drp *drp_ie) 680{ 681 struct uwb_rsv *rsv; 682 683 rsv = uwb_rsv_find(rc, src, drp_ie); 684 if (!rsv) { 685 /* 686 * No reservation? It's either for a recently 687 * terminated reservation; or the DRP IE couldn't be 688 * processed (e.g., an invalid IE or out of memory). 689 */ 690 return; 691 } 692 693 /* 694 * Do nothing with DRP IEs for reservations that have been 695 * terminated. 696 */ 697 if (rsv->state == UWB_RSV_STATE_NONE) { 698 uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); 699 return; 700 } 701 702 if (uwb_ie_drp_owner(drp_ie)) 703 uwb_drp_process_target(rc, rsv, drp_ie, drp_evt); 704 else 705 uwb_drp_process_owner(rc, rsv, src, drp_ie, drp_evt); 706 707} 708 709 710static bool uwb_drp_involves_us(struct uwb_rc *rc, struct uwb_ie_drp *drp_ie) 711{ 712 return uwb_dev_addr_cmp(&rc->uwb_dev.dev_addr, &drp_ie->dev_addr) == 0; 713} 714 715/* 716 * Process a received DRP IE. 717 */ 718static void uwb_drp_process(struct uwb_rc *rc, struct uwb_rc_evt_drp *drp_evt, 719 struct uwb_dev *src, struct uwb_ie_drp *drp_ie) 720{ 721 if (uwb_ie_drp_type(drp_ie) == UWB_DRP_TYPE_ALIEN_BP) 722 uwb_drp_handle_alien_drp(rc, drp_ie); 723 else if (uwb_drp_involves_us(rc, drp_ie)) 724 uwb_drp_process_involved(rc, src, drp_evt, drp_ie); 725 else 726 uwb_drp_process_not_involved(rc, drp_evt, drp_ie); 727} 728 729/* 730 * Process a received DRP Availability IE 731 */ 732static void uwb_drp_availability_process(struct uwb_rc *rc, struct uwb_dev *src, 733 struct uwb_ie_drp_avail *drp_availability_ie) 734{ 735 bitmap_copy(src->last_availability_bm, 736 drp_availability_ie->bmp, UWB_NUM_MAS); 737} 738 739/* 740 * Process all the DRP IEs (both DRP IEs and the DRP Availability IE) 741 * from a device. 742 */ 743static 744void uwb_drp_process_all(struct uwb_rc *rc, struct uwb_rc_evt_drp *drp_evt, 745 size_t ielen, struct uwb_dev *src_dev) 746{ 747 struct device *dev = &rc->uwb_dev.dev; 748 struct uwb_ie_hdr *ie_hdr; 749 void *ptr; 750 751 ptr = drp_evt->ie_data; 752 for (;;) { 753 ie_hdr = uwb_ie_next(&ptr, &ielen); 754 if (!ie_hdr) 755 break; 756 757 switch (ie_hdr->element_id) { 758 case UWB_IE_DRP_AVAILABILITY: 759 uwb_drp_availability_process(rc, src_dev, (struct uwb_ie_drp_avail *)ie_hdr); 760 break; 761 case UWB_IE_DRP: 762 uwb_drp_process(rc, drp_evt, src_dev, (struct uwb_ie_drp *)ie_hdr); 763 break; 764 default: 765 dev_warn(dev, "unexpected IE in DRP notification\n"); 766 break; 767 } 768 } 769 770 if (ielen > 0) 771 dev_warn(dev, "%d octets remaining in DRP notification\n", 772 (int)ielen); 773} 774 775/** 776 * uwbd_evt_handle_rc_drp - handle a DRP_IE event 777 * @evt: the DRP_IE event from the radio controller 778 * 779 * This processes DRP notifications from the radio controller, either 780 * initiating a new reservation or transitioning an existing 781 * reservation into a different state. 782 * 783 * DRP notifications can occur for three different reasons: 784 * 785 * - UWB_DRP_NOTIF_DRP_IE_RECVD: one or more DRP IEs with the RC as 786 * the target or source have been received. 787 * 788 * These DRP IEs could be new or for an existing reservation. 789 * 790 * If the DRP IE for an existing reservation ceases to be to 791 * received for at least mMaxLostBeacons, the reservation should be 792 * considered to be terminated. Note that the TERMINATE reason (see 793 * below) may not always be signalled (e.g., the remote device has 794 * two or more reservations established with the RC). 795 * 796 * - UWB_DRP_NOTIF_CONFLICT: DRP IEs from any device in the beacon 797 * group conflict with the RC's reservations. 798 * 799 * - UWB_DRP_NOTIF_TERMINATE: DRP IEs are no longer being received 800 * from a device (i.e., it's terminated all reservations). 801 * 802 * Only the software state of the reservations is changed; the setting 803 * of the radio controller's DRP IEs is done after all the events in 804 * an event buffer are processed. This saves waiting multiple times 805 * for the SET_DRP_IE command to complete. 806 */ 807int uwbd_evt_handle_rc_drp(struct uwb_event *evt) 808{ 809 struct device *dev = &evt->rc->uwb_dev.dev; 810 struct uwb_rc *rc = evt->rc; 811 struct uwb_rc_evt_drp *drp_evt; 812 size_t ielength, bytes_left; 813 struct uwb_dev_addr src_addr; 814 struct uwb_dev *src_dev; 815 816 /* Is there enough data to decode the event (and any IEs in 817 its payload)? */ 818 if (evt->notif.size < sizeof(*drp_evt)) { 819 dev_err(dev, "DRP event: Not enough data to decode event " 820 "[%zu bytes left, %zu needed]\n", 821 evt->notif.size, sizeof(*drp_evt)); 822 return 0; 823 } 824 bytes_left = evt->notif.size - sizeof(*drp_evt); 825 drp_evt = container_of(evt->notif.rceb, struct uwb_rc_evt_drp, rceb); 826 ielength = le16_to_cpu(drp_evt->ie_length); 827 if (bytes_left != ielength) { 828 dev_err(dev, "DRP event: Not enough data in payload [%zu" 829 "bytes left, %zu declared in the event]\n", 830 bytes_left, ielength); 831 return 0; 832 } 833 834 memcpy(src_addr.data, &drp_evt->src_addr, sizeof(src_addr)); 835 src_dev = uwb_dev_get_by_devaddr(rc, &src_addr); 836 if (!src_dev) { 837 /* 838 * A DRP notification from an unrecognized device. 839 * 840 * This is probably from a WUSB device that doesn't 841 * have an EUI-48 and therefore doesn't show up in the 842 * UWB device database. It's safe to simply ignore 843 * these. 844 */ 845 return 0; 846 } 847 848 mutex_lock(&rc->rsvs_mutex); 849 850 /* We do not distinguish from the reason */ 851 uwb_drp_process_all(rc, drp_evt, ielength, src_dev); 852 853 mutex_unlock(&rc->rsvs_mutex); 854 855 uwb_dev_put(src_dev); 856 return 0; 857} 858