1 /* 2 * bcm.c - Broadcast Manager to filter/send (cyclic) CAN content 3 * 4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of Volkswagen nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * Alternatively, provided that this notice is retained in full, this 20 * software may be distributed under the terms of the GNU General 21 * Public License ("GPL") version 2, in which case the provisions of the 22 * GPL apply INSTEAD OF those given above. 23 * 24 * The provided data structures and external interfaces from this code 25 * are not restricted to be used by modules with a GPL compatible license. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 38 * DAMAGE. 39 * 40 * Send feedback to <socketcan-users@lists.berlios.de> 41 * 42 */ 43 44 #include <linux/module.h> 45 #include <linux/init.h> 46 #include <linux/hrtimer.h> 47 #include <linux/list.h> 48 #include <linux/proc_fs.h> 49 #include <linux/uio.h> 50 #include <linux/net.h> 51 #include <linux/netdevice.h> 52 #include <linux/socket.h> 53 #include <linux/if_arp.h> 54 #include <linux/skbuff.h> 55 #include <linux/can.h> 56 #include <linux/can/core.h> 57 #include <linux/can/bcm.h> 58 #include <net/sock.h> 59 #include <net/net_namespace.h> 60 61 /* use of last_frames[index].can_dlc */ 62 #define RX_RECV 0x40 /* received data for this element */ 63 #define RX_THR 0x80 /* element not been sent due to throttle feature */ 64 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */ 65 66 /* get best masking value for can_rx_register() for a given single can_id */ 67 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \ 68 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \ 69 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG)) 70 71 #define CAN_BCM_VERSION CAN_VERSION 72 static __initdata const char banner[] = KERN_INFO 73 "can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n"; 74 75 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol"); 76 MODULE_LICENSE("Dual BSD/GPL"); 77 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); 78 MODULE_ALIAS("can-proto-2"); 79 80 /* easy access to can_frame payload */ 81 static inline u64 GET_U64(const struct can_frame *cp) 82 { 83 return *(u64 *)cp->data; 84 } 85 86 struct bcm_op { 87 struct list_head list; 88 int ifindex; 89 canid_t can_id; 90 int flags; 91 unsigned long frames_abs, frames_filtered; 92 struct timeval ival1, ival2; 93 struct hrtimer timer, thrtimer; 94 struct tasklet_struct tsklet, thrtsklet; 95 ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg; 96 int rx_ifindex; 97 int count; 98 int nframes; 99 int currframe; 100 struct can_frame *frames; 101 struct can_frame *last_frames; 102 struct can_frame sframe; 103 struct can_frame last_sframe; 104 struct sock *sk; 105 struct net_device *rx_reg_dev; 106 }; 107 108 static struct proc_dir_entry *proc_dir; 109 110 struct bcm_sock { 111 struct sock sk; 112 int bound; 113 int ifindex; 114 struct notifier_block notifier; 115 struct list_head rx_ops; 116 struct list_head tx_ops; 117 unsigned long dropped_usr_msgs; 118 struct proc_dir_entry *bcm_proc_read; 119 char procname [9]; /* pointer printed in ASCII with \0 */ 120 }; 121 122 static inline struct bcm_sock *bcm_sk(const struct sock *sk) 123 { 124 return (struct bcm_sock *)sk; 125 } 126 127 #define CFSIZ sizeof(struct can_frame) 128 #define OPSIZ sizeof(struct bcm_op) 129 #define MHSIZ sizeof(struct bcm_msg_head) 130 131 /* 132 * procfs functions 133 */ 134 static char *bcm_proc_getifname(int ifindex) 135 { 136 struct net_device *dev; 137 138 if (!ifindex) 139 return "any"; 140 141 /* no usage counting */ 142 dev = __dev_get_by_index(&init_net, ifindex); 143 if (dev) 144 return dev->name; 145 146 return "???"; 147 } 148 149 static int bcm_read_proc(char *page, char **start, off_t off, 150 int count, int *eof, void *data) 151 { 152 int len = 0; 153 struct sock *sk = (struct sock *)data; 154 struct bcm_sock *bo = bcm_sk(sk); 155 struct bcm_op *op; 156 157 len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p", 158 sk->sk_socket); 159 len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk); 160 len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo); 161 len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu", 162 bo->dropped_usr_msgs); 163 len += snprintf(page + len, PAGE_SIZE - len, " / bound %s", 164 bcm_proc_getifname(bo->ifindex)); 165 len += snprintf(page + len, PAGE_SIZE - len, " <<<\n"); 166 167 list_for_each_entry(op, &bo->rx_ops, list) { 168 169 unsigned long reduction; 170 171 /* print only active entries & prevent division by zero */ 172 if (!op->frames_abs) 173 continue; 174 175 len += snprintf(page + len, PAGE_SIZE - len, 176 "rx_op: %03X %-5s ", 177 op->can_id, bcm_proc_getifname(op->ifindex)); 178 len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ", 179 op->nframes, 180 (op->flags & RX_CHECK_DLC)?'d':' '); 181 if (op->kt_ival1.tv64) 182 len += snprintf(page + len, PAGE_SIZE - len, 183 "timeo=%lld ", 184 (long long) 185 ktime_to_us(op->kt_ival1)); 186 187 if (op->kt_ival2.tv64) 188 len += snprintf(page + len, PAGE_SIZE - len, 189 "thr=%lld ", 190 (long long) 191 ktime_to_us(op->kt_ival2)); 192 193 len += snprintf(page + len, PAGE_SIZE - len, 194 "# recv %ld (%ld) => reduction: ", 195 op->frames_filtered, op->frames_abs); 196 197 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs; 198 199 len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n", 200 (reduction == 100)?"near ":"", reduction); 201 202 if (len > PAGE_SIZE - 200) { 203 /* mark output cut off */ 204 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n"); 205 break; 206 } 207 } 208 209 list_for_each_entry(op, &bo->tx_ops, list) { 210 211 len += snprintf(page + len, PAGE_SIZE - len, 212 "tx_op: %03X %s [%d] ", 213 op->can_id, bcm_proc_getifname(op->ifindex), 214 op->nframes); 215 216 if (op->kt_ival1.tv64) 217 len += snprintf(page + len, PAGE_SIZE - len, "t1=%lld ", 218 (long long) ktime_to_us(op->kt_ival1)); 219 220 if (op->kt_ival2.tv64) 221 len += snprintf(page + len, PAGE_SIZE - len, "t2=%lld ", 222 (long long) ktime_to_us(op->kt_ival2)); 223 224 len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n", 225 op->frames_abs); 226 227 if (len > PAGE_SIZE - 100) { 228 /* mark output cut off */ 229 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n"); 230 break; 231 } 232 } 233 234 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 235 236 *eof = 1; 237 return len; 238 } 239 240 /* 241 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface 242 * of the given bcm tx op 243 */ 244 static void bcm_can_tx(struct bcm_op *op) 245 { 246 struct sk_buff *skb; 247 struct net_device *dev; 248 struct can_frame *cf = &op->frames[op->currframe]; 249 250 /* no target device? => exit */ 251 if (!op->ifindex) 252 return; 253 254 dev = dev_get_by_index(&init_net, op->ifindex); 255 if (!dev) { 256 /* RFC: should this bcm_op remove itself here? */ 257 return; 258 } 259 260 skb = alloc_skb(CFSIZ, gfp_any()); 261 if (!skb) 262 goto out; 263 264 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ); 265 266 /* send with loopback */ 267 skb->dev = dev; 268 skb->sk = op->sk; 269 can_send(skb, 1); 270 271 /* update statistics */ 272 op->currframe++; 273 op->frames_abs++; 274 275 /* reached last frame? */ 276 if (op->currframe >= op->nframes) 277 op->currframe = 0; 278 out: 279 dev_put(dev); 280 } 281 282 /* 283 * bcm_send_to_user - send a BCM message to the userspace 284 * (consisting of bcm_msg_head + x CAN frames) 285 */ 286 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, 287 struct can_frame *frames, int has_timestamp) 288 { 289 struct sk_buff *skb; 290 struct can_frame *firstframe; 291 struct sockaddr_can *addr; 292 struct sock *sk = op->sk; 293 int datalen = head->nframes * CFSIZ; 294 int err; 295 296 skb = alloc_skb(sizeof(*head) + datalen, gfp_any()); 297 if (!skb) 298 return; 299 300 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head)); 301 302 if (head->nframes) { 303 /* can_frames starting here */ 304 firstframe = (struct can_frame *)skb_tail_pointer(skb); 305 306 memcpy(skb_put(skb, datalen), frames, datalen); 307 308 /* 309 * the BCM uses the can_dlc-element of the can_frame 310 * structure for internal purposes. This is only 311 * relevant for updates that are generated by the 312 * BCM, where nframes is 1 313 */ 314 if (head->nframes == 1) 315 firstframe->can_dlc &= BCM_CAN_DLC_MASK; 316 } 317 318 if (has_timestamp) { 319 /* restore rx timestamp */ 320 skb->tstamp = op->rx_stamp; 321 } 322 323 /* 324 * Put the datagram to the queue so that bcm_recvmsg() can 325 * get it from there. We need to pass the interface index to 326 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb 327 * containing the interface index. 328 */ 329 330 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can)); 331 addr = (struct sockaddr_can *)skb->cb; 332 memset(addr, 0, sizeof(*addr)); 333 addr->can_family = AF_CAN; 334 addr->can_ifindex = op->rx_ifindex; 335 336 err = sock_queue_rcv_skb(sk, skb); 337 if (err < 0) { 338 struct bcm_sock *bo = bcm_sk(sk); 339 340 kfree_skb(skb); 341 /* don't care about overflows in this statistic */ 342 bo->dropped_usr_msgs++; 343 } 344 } 345 346 static void bcm_tx_timeout_tsklet(unsigned long data) 347 { 348 struct bcm_op *op = (struct bcm_op *)data; 349 struct bcm_msg_head msg_head; 350 351 if (op->kt_ival1.tv64 && (op->count > 0)) { 352 353 op->count--; 354 if (!op->count && (op->flags & TX_COUNTEVT)) { 355 356 /* create notification to user */ 357 msg_head.opcode = TX_EXPIRED; 358 msg_head.flags = op->flags; 359 msg_head.count = op->count; 360 msg_head.ival1 = op->ival1; 361 msg_head.ival2 = op->ival2; 362 msg_head.can_id = op->can_id; 363 msg_head.nframes = 0; 364 365 bcm_send_to_user(op, &msg_head, NULL, 0); 366 } 367 } 368 369 if (op->kt_ival1.tv64 && (op->count > 0)) { 370 371 /* send (next) frame */ 372 bcm_can_tx(op); 373 hrtimer_start(&op->timer, 374 ktime_add(ktime_get(), op->kt_ival1), 375 HRTIMER_MODE_ABS); 376 377 } else { 378 if (op->kt_ival2.tv64) { 379 380 /* send (next) frame */ 381 bcm_can_tx(op); 382 hrtimer_start(&op->timer, 383 ktime_add(ktime_get(), op->kt_ival2), 384 HRTIMER_MODE_ABS); 385 } 386 } 387 } 388 389 /* 390 * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions 391 */ 392 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer) 393 { 394 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 395 396 tasklet_schedule(&op->tsklet); 397 398 return HRTIMER_NORESTART; 399 } 400 401 /* 402 * bcm_rx_changed - create a RX_CHANGED notification due to changed content 403 */ 404 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data) 405 { 406 struct bcm_msg_head head; 407 408 /* update statistics */ 409 op->frames_filtered++; 410 411 /* prevent statistics overflow */ 412 if (op->frames_filtered > ULONG_MAX/100) 413 op->frames_filtered = op->frames_abs = 0; 414 415 /* this element is not throttled anymore */ 416 data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV); 417 418 head.opcode = RX_CHANGED; 419 head.flags = op->flags; 420 head.count = op->count; 421 head.ival1 = op->ival1; 422 head.ival2 = op->ival2; 423 head.can_id = op->can_id; 424 head.nframes = 1; 425 426 bcm_send_to_user(op, &head, data, 1); 427 } 428 429 /* 430 * bcm_rx_update_and_send - process a detected relevant receive content change 431 * 1. update the last received data 432 * 2. send a notification to the user (if possible) 433 */ 434 static void bcm_rx_update_and_send(struct bcm_op *op, 435 struct can_frame *lastdata, 436 const struct can_frame *rxdata) 437 { 438 memcpy(lastdata, rxdata, CFSIZ); 439 440 /* mark as used and throttled by default */ 441 lastdata->can_dlc |= (RX_RECV|RX_THR); 442 443 /* throtteling mode inactive ? */ 444 if (!op->kt_ival2.tv64) { 445 /* send RX_CHANGED to the user immediately */ 446 bcm_rx_changed(op, lastdata); 447 return; 448 } 449 450 /* with active throttling timer we are just done here */ 451 if (hrtimer_active(&op->thrtimer)) 452 return; 453 454 /* first receiption with enabled throttling mode */ 455 if (!op->kt_lastmsg.tv64) 456 goto rx_changed_settime; 457 458 /* got a second frame inside a potential throttle period? */ 459 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) < 460 ktime_to_us(op->kt_ival2)) { 461 /* do not send the saved data - only start throttle timer */ 462 hrtimer_start(&op->thrtimer, 463 ktime_add(op->kt_lastmsg, op->kt_ival2), 464 HRTIMER_MODE_ABS); 465 return; 466 } 467 468 /* the gap was that big, that throttling was not needed here */ 469 rx_changed_settime: 470 bcm_rx_changed(op, lastdata); 471 op->kt_lastmsg = ktime_get(); 472 } 473 474 /* 475 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly 476 * received data stored in op->last_frames[] 477 */ 478 static void bcm_rx_cmp_to_index(struct bcm_op *op, int index, 479 const struct can_frame *rxdata) 480 { 481 /* 482 * no one uses the MSBs of can_dlc for comparation, 483 * so we use it here to detect the first time of reception 484 */ 485 486 if (!(op->last_frames[index].can_dlc & RX_RECV)) { 487 /* received data for the first time => send update to user */ 488 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 489 return; 490 } 491 492 /* do a real check in can_frame data section */ 493 494 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) != 495 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) { 496 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 497 return; 498 } 499 500 if (op->flags & RX_CHECK_DLC) { 501 /* do a real check in can_frame dlc */ 502 if (rxdata->can_dlc != (op->last_frames[index].can_dlc & 503 BCM_CAN_DLC_MASK)) { 504 bcm_rx_update_and_send(op, &op->last_frames[index], 505 rxdata); 506 return; 507 } 508 } 509 } 510 511 /* 512 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption 513 */ 514 static void bcm_rx_starttimer(struct bcm_op *op) 515 { 516 if (op->flags & RX_NO_AUTOTIMER) 517 return; 518 519 if (op->kt_ival1.tv64) 520 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL); 521 } 522 523 static void bcm_rx_timeout_tsklet(unsigned long data) 524 { 525 struct bcm_op *op = (struct bcm_op *)data; 526 struct bcm_msg_head msg_head; 527 528 /* create notification to user */ 529 msg_head.opcode = RX_TIMEOUT; 530 msg_head.flags = op->flags; 531 msg_head.count = op->count; 532 msg_head.ival1 = op->ival1; 533 msg_head.ival2 = op->ival2; 534 msg_head.can_id = op->can_id; 535 msg_head.nframes = 0; 536 537 bcm_send_to_user(op, &msg_head, NULL, 0); 538 } 539 540 /* 541 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out 542 */ 543 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer) 544 { 545 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 546 547 /* schedule before NET_RX_SOFTIRQ */ 548 tasklet_hi_schedule(&op->tsklet); 549 550 /* no restart of the timer is done here! */ 551 552 /* if user wants to be informed, when cyclic CAN-Messages come back */ 553 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) { 554 /* clear received can_frames to indicate 'nothing received' */ 555 memset(op->last_frames, 0, op->nframes * CFSIZ); 556 } 557 558 return HRTIMER_NORESTART; 559 } 560 561 /* 562 * bcm_rx_do_flush - helper for bcm_rx_thr_flush 563 */ 564 static inline int bcm_rx_do_flush(struct bcm_op *op, int update, int index) 565 { 566 if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) { 567 if (update) 568 bcm_rx_changed(op, &op->last_frames[index]); 569 return 1; 570 } 571 return 0; 572 } 573 574 /* 575 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace 576 * 577 * update == 0 : just check if throttled data is available (any irq context) 578 * update == 1 : check and send throttled data to userspace (soft_irq context) 579 */ 580 static int bcm_rx_thr_flush(struct bcm_op *op, int update) 581 { 582 int updated = 0; 583 584 if (op->nframes > 1) { 585 int i; 586 587 /* for MUX filter we start at index 1 */ 588 for (i = 1; i < op->nframes; i++) 589 updated += bcm_rx_do_flush(op, update, i); 590 591 } else { 592 /* for RX_FILTER_ID and simple filter */ 593 updated += bcm_rx_do_flush(op, update, 0); 594 } 595 596 return updated; 597 } 598 599 static void bcm_rx_thr_tsklet(unsigned long data) 600 { 601 struct bcm_op *op = (struct bcm_op *)data; 602 603 /* push the changed data to the userspace */ 604 bcm_rx_thr_flush(op, 1); 605 } 606 607 /* 608 * bcm_rx_thr_handler - the time for blocked content updates is over now: 609 * Check for throttled data and send it to the userspace 610 */ 611 static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer) 612 { 613 struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer); 614 615 tasklet_schedule(&op->thrtsklet); 616 617 if (bcm_rx_thr_flush(op, 0)) { 618 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2); 619 return HRTIMER_RESTART; 620 } else { 621 /* rearm throttle handling */ 622 op->kt_lastmsg = ktime_set(0, 0); 623 return HRTIMER_NORESTART; 624 } 625 } 626 627 /* 628 * bcm_rx_handler - handle a CAN frame receiption 629 */ 630 static void bcm_rx_handler(struct sk_buff *skb, void *data) 631 { 632 struct bcm_op *op = (struct bcm_op *)data; 633 const struct can_frame *rxframe = (struct can_frame *)skb->data; 634 int i; 635 636 /* disable timeout */ 637 hrtimer_cancel(&op->timer); 638 639 if (op->can_id != rxframe->can_id) 640 return; 641 642 /* save rx timestamp */ 643 op->rx_stamp = skb->tstamp; 644 /* save originator for recvfrom() */ 645 op->rx_ifindex = skb->dev->ifindex; 646 /* update statistics */ 647 op->frames_abs++; 648 649 if (op->flags & RX_RTR_FRAME) { 650 /* send reply for RTR-request (placed in op->frames[0]) */ 651 bcm_can_tx(op); 652 return; 653 } 654 655 if (op->flags & RX_FILTER_ID) { 656 /* the easiest case */ 657 bcm_rx_update_and_send(op, &op->last_frames[0], rxframe); 658 goto rx_starttimer; 659 } 660 661 if (op->nframes == 1) { 662 /* simple compare with index 0 */ 663 bcm_rx_cmp_to_index(op, 0, rxframe); 664 goto rx_starttimer; 665 } 666 667 if (op->nframes > 1) { 668 /* 669 * multiplex compare 670 * 671 * find the first multiplex mask that fits. 672 * Remark: The MUX-mask is stored in index 0 673 */ 674 675 for (i = 1; i < op->nframes; i++) { 676 if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) == 677 (GET_U64(&op->frames[0]) & 678 GET_U64(&op->frames[i]))) { 679 bcm_rx_cmp_to_index(op, i, rxframe); 680 break; 681 } 682 } 683 } 684 685 rx_starttimer: 686 bcm_rx_starttimer(op); 687 } 688 689 /* 690 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements 691 */ 692 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id, 693 int ifindex) 694 { 695 struct bcm_op *op; 696 697 list_for_each_entry(op, ops, list) { 698 if ((op->can_id == can_id) && (op->ifindex == ifindex)) 699 return op; 700 } 701 702 return NULL; 703 } 704 705 static void bcm_remove_op(struct bcm_op *op) 706 { 707 hrtimer_cancel(&op->timer); 708 hrtimer_cancel(&op->thrtimer); 709 710 if (op->tsklet.func) 711 tasklet_kill(&op->tsklet); 712 713 if (op->thrtsklet.func) 714 tasklet_kill(&op->thrtsklet); 715 716 if ((op->frames) && (op->frames != &op->sframe)) 717 kfree(op->frames); 718 719 if ((op->last_frames) && (op->last_frames != &op->last_sframe)) 720 kfree(op->last_frames); 721 722 kfree(op); 723 724 return; 725 } 726 727 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op) 728 { 729 if (op->rx_reg_dev == dev) { 730 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id), 731 bcm_rx_handler, op); 732 733 /* mark as removed subscription */ 734 op->rx_reg_dev = NULL; 735 } else 736 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device " 737 "mismatch %p %p\n", op->rx_reg_dev, dev); 738 } 739 740 /* 741 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops) 742 */ 743 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex) 744 { 745 struct bcm_op *op, *n; 746 747 list_for_each_entry_safe(op, n, ops, list) { 748 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 749 750 /* 751 * Don't care if we're bound or not (due to netdev 752 * problems) can_rx_unregister() is always a save 753 * thing to do here. 754 */ 755 if (op->ifindex) { 756 /* 757 * Only remove subscriptions that had not 758 * been removed due to NETDEV_UNREGISTER 759 * in bcm_notifier() 760 */ 761 if (op->rx_reg_dev) { 762 struct net_device *dev; 763 764 dev = dev_get_by_index(&init_net, 765 op->ifindex); 766 if (dev) { 767 bcm_rx_unreg(dev, op); 768 dev_put(dev); 769 } 770 } 771 } else 772 can_rx_unregister(NULL, op->can_id, 773 REGMASK(op->can_id), 774 bcm_rx_handler, op); 775 776 list_del(&op->list); 777 bcm_remove_op(op); 778 return 1; /* done */ 779 } 780 } 781 782 return 0; /* not found */ 783 } 784 785 /* 786 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops) 787 */ 788 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex) 789 { 790 struct bcm_op *op, *n; 791 792 list_for_each_entry_safe(op, n, ops, list) { 793 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 794 list_del(&op->list); 795 bcm_remove_op(op); 796 return 1; /* done */ 797 } 798 } 799 800 return 0; /* not found */ 801 } 802 803 /* 804 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg) 805 */ 806 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head, 807 int ifindex) 808 { 809 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex); 810 811 if (!op) 812 return -EINVAL; 813 814 /* put current values into msg_head */ 815 msg_head->flags = op->flags; 816 msg_head->count = op->count; 817 msg_head->ival1 = op->ival1; 818 msg_head->ival2 = op->ival2; 819 msg_head->nframes = op->nframes; 820 821 bcm_send_to_user(op, msg_head, op->frames, 0); 822 823 return MHSIZ; 824 } 825 826 /* 827 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg) 828 */ 829 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 830 int ifindex, struct sock *sk) 831 { 832 struct bcm_sock *bo = bcm_sk(sk); 833 struct bcm_op *op; 834 int i, err; 835 836 /* we need a real device to send frames */ 837 if (!ifindex) 838 return -ENODEV; 839 840 /* we need at least one can_frame */ 841 if (msg_head->nframes < 1) 842 return -EINVAL; 843 844 /* check the given can_id */ 845 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex); 846 847 if (op) { 848 /* update existing BCM operation */ 849 850 /* 851 * Do we need more space for the can_frames than currently 852 * allocated? -> This is a _really_ unusual use-case and 853 * therefore (complexity / locking) it is not supported. 854 */ 855 if (msg_head->nframes > op->nframes) 856 return -E2BIG; 857 858 /* update can_frames content */ 859 for (i = 0; i < msg_head->nframes; i++) { 860 err = memcpy_fromiovec((u8 *)&op->frames[i], 861 msg->msg_iov, CFSIZ); 862 863 if (op->frames[i].can_dlc > 8) 864 err = -EINVAL; 865 866 if (err < 0) 867 return err; 868 869 if (msg_head->flags & TX_CP_CAN_ID) { 870 /* copy can_id into frame */ 871 op->frames[i].can_id = msg_head->can_id; 872 } 873 } 874 875 } else { 876 /* insert new BCM operation for the given can_id */ 877 878 op = kzalloc(OPSIZ, GFP_KERNEL); 879 if (!op) 880 return -ENOMEM; 881 882 op->can_id = msg_head->can_id; 883 884 /* create array for can_frames and copy the data */ 885 if (msg_head->nframes > 1) { 886 op->frames = kmalloc(msg_head->nframes * CFSIZ, 887 GFP_KERNEL); 888 if (!op->frames) { 889 kfree(op); 890 return -ENOMEM; 891 } 892 } else 893 op->frames = &op->sframe; 894 895 for (i = 0; i < msg_head->nframes; i++) { 896 err = memcpy_fromiovec((u8 *)&op->frames[i], 897 msg->msg_iov, CFSIZ); 898 899 if (op->frames[i].can_dlc > 8) 900 err = -EINVAL; 901 902 if (err < 0) { 903 if (op->frames != &op->sframe) 904 kfree(op->frames); 905 kfree(op); 906 return err; 907 } 908 909 if (msg_head->flags & TX_CP_CAN_ID) { 910 /* copy can_id into frame */ 911 op->frames[i].can_id = msg_head->can_id; 912 } 913 } 914 915 /* tx_ops never compare with previous received messages */ 916 op->last_frames = NULL; 917 918 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 919 op->sk = sk; 920 op->ifindex = ifindex; 921 922 /* initialize uninitialized (kzalloc) structure */ 923 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 924 op->timer.function = bcm_tx_timeout_handler; 925 926 /* initialize tasklet for tx countevent notification */ 927 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet, 928 (unsigned long) op); 929 930 /* currently unused in tx_ops */ 931 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 932 933 /* add this bcm_op to the list of the tx_ops */ 934 list_add(&op->list, &bo->tx_ops); 935 936 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */ 937 938 if (op->nframes != msg_head->nframes) { 939 op->nframes = msg_head->nframes; 940 /* start multiple frame transmission with index 0 */ 941 op->currframe = 0; 942 } 943 944 /* check flags */ 945 946 op->flags = msg_head->flags; 947 948 if (op->flags & TX_RESET_MULTI_IDX) { 949 /* start multiple frame transmission with index 0 */ 950 op->currframe = 0; 951 } 952 953 if (op->flags & SETTIMER) { 954 /* set timer values */ 955 op->count = msg_head->count; 956 op->ival1 = msg_head->ival1; 957 op->ival2 = msg_head->ival2; 958 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 959 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 960 961 /* disable an active timer due to zero values? */ 962 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64) 963 hrtimer_cancel(&op->timer); 964 } 965 966 if ((op->flags & STARTTIMER) && 967 ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) { 968 969 /* spec: send can_frame when starting timer */ 970 op->flags |= TX_ANNOUNCE; 971 972 if (op->kt_ival1.tv64 && (op->count > 0)) { 973 /* op->count-- is done in bcm_tx_timeout_handler */ 974 hrtimer_start(&op->timer, op->kt_ival1, 975 HRTIMER_MODE_REL); 976 } else 977 hrtimer_start(&op->timer, op->kt_ival2, 978 HRTIMER_MODE_REL); 979 } 980 981 if (op->flags & TX_ANNOUNCE) 982 bcm_can_tx(op); 983 984 return msg_head->nframes * CFSIZ + MHSIZ; 985 } 986 987 /* 988 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg) 989 */ 990 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 991 int ifindex, struct sock *sk) 992 { 993 struct bcm_sock *bo = bcm_sk(sk); 994 struct bcm_op *op; 995 int do_rx_register; 996 int err = 0; 997 998 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) { 999 /* be robust against wrong usage ... */ 1000 msg_head->flags |= RX_FILTER_ID; 1001 /* ignore trailing garbage */ 1002 msg_head->nframes = 0; 1003 } 1004 1005 if ((msg_head->flags & RX_RTR_FRAME) && 1006 ((msg_head->nframes != 1) || 1007 (!(msg_head->can_id & CAN_RTR_FLAG)))) 1008 return -EINVAL; 1009 1010 /* check the given can_id */ 1011 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex); 1012 if (op) { 1013 /* update existing BCM operation */ 1014 1015 /* 1016 * Do we need more space for the can_frames than currently 1017 * allocated? -> This is a _really_ unusual use-case and 1018 * therefore (complexity / locking) it is not supported. 1019 */ 1020 if (msg_head->nframes > op->nframes) 1021 return -E2BIG; 1022 1023 if (msg_head->nframes) { 1024 /* update can_frames content */ 1025 err = memcpy_fromiovec((u8 *)op->frames, 1026 msg->msg_iov, 1027 msg_head->nframes * CFSIZ); 1028 if (err < 0) 1029 return err; 1030 1031 /* clear last_frames to indicate 'nothing received' */ 1032 memset(op->last_frames, 0, msg_head->nframes * CFSIZ); 1033 } 1034 1035 op->nframes = msg_head->nframes; 1036 1037 /* Only an update -> do not call can_rx_register() */ 1038 do_rx_register = 0; 1039 1040 } else { 1041 /* insert new BCM operation for the given can_id */ 1042 op = kzalloc(OPSIZ, GFP_KERNEL); 1043 if (!op) 1044 return -ENOMEM; 1045 1046 op->can_id = msg_head->can_id; 1047 op->nframes = msg_head->nframes; 1048 1049 if (msg_head->nframes > 1) { 1050 /* create array for can_frames and copy the data */ 1051 op->frames = kmalloc(msg_head->nframes * CFSIZ, 1052 GFP_KERNEL); 1053 if (!op->frames) { 1054 kfree(op); 1055 return -ENOMEM; 1056 } 1057 1058 /* create and init array for received can_frames */ 1059 op->last_frames = kzalloc(msg_head->nframes * CFSIZ, 1060 GFP_KERNEL); 1061 if (!op->last_frames) { 1062 kfree(op->frames); 1063 kfree(op); 1064 return -ENOMEM; 1065 } 1066 1067 } else { 1068 op->frames = &op->sframe; 1069 op->last_frames = &op->last_sframe; 1070 } 1071 1072 if (msg_head->nframes) { 1073 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov, 1074 msg_head->nframes * CFSIZ); 1075 if (err < 0) { 1076 if (op->frames != &op->sframe) 1077 kfree(op->frames); 1078 if (op->last_frames != &op->last_sframe) 1079 kfree(op->last_frames); 1080 kfree(op); 1081 return err; 1082 } 1083 } 1084 1085 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 1086 op->sk = sk; 1087 op->ifindex = ifindex; 1088 1089 /* initialize uninitialized (kzalloc) structure */ 1090 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1091 op->timer.function = bcm_rx_timeout_handler; 1092 1093 /* initialize tasklet for rx timeout notification */ 1094 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet, 1095 (unsigned long) op); 1096 1097 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1098 op->thrtimer.function = bcm_rx_thr_handler; 1099 1100 /* initialize tasklet for rx throttle handling */ 1101 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet, 1102 (unsigned long) op); 1103 1104 /* add this bcm_op to the list of the rx_ops */ 1105 list_add(&op->list, &bo->rx_ops); 1106 1107 /* call can_rx_register() */ 1108 do_rx_register = 1; 1109 1110 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */ 1111 1112 /* check flags */ 1113 op->flags = msg_head->flags; 1114 1115 if (op->flags & RX_RTR_FRAME) { 1116 1117 /* no timers in RTR-mode */ 1118 hrtimer_cancel(&op->thrtimer); 1119 hrtimer_cancel(&op->timer); 1120 1121 /* 1122 * funny feature in RX(!)_SETUP only for RTR-mode: 1123 * copy can_id into frame BUT without RTR-flag to 1124 * prevent a full-load-loopback-test ... ;-] 1125 */ 1126 if ((op->flags & TX_CP_CAN_ID) || 1127 (op->frames[0].can_id == op->can_id)) 1128 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG; 1129 1130 } else { 1131 if (op->flags & SETTIMER) { 1132 1133 /* set timer value */ 1134 op->ival1 = msg_head->ival1; 1135 op->ival2 = msg_head->ival2; 1136 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 1137 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 1138 1139 /* disable an active timer due to zero value? */ 1140 if (!op->kt_ival1.tv64) 1141 hrtimer_cancel(&op->timer); 1142 1143 /* 1144 * In any case cancel the throttle timer, flush 1145 * potentially blocked msgs and reset throttle handling 1146 */ 1147 op->kt_lastmsg = ktime_set(0, 0); 1148 hrtimer_cancel(&op->thrtimer); 1149 bcm_rx_thr_flush(op, 1); 1150 } 1151 1152 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64) 1153 hrtimer_start(&op->timer, op->kt_ival1, 1154 HRTIMER_MODE_REL); 1155 } 1156 1157 /* now we can register for can_ids, if we added a new bcm_op */ 1158 if (do_rx_register) { 1159 if (ifindex) { 1160 struct net_device *dev; 1161 1162 dev = dev_get_by_index(&init_net, ifindex); 1163 if (dev) { 1164 err = can_rx_register(dev, op->can_id, 1165 REGMASK(op->can_id), 1166 bcm_rx_handler, op, 1167 "bcm"); 1168 1169 op->rx_reg_dev = dev; 1170 dev_put(dev); 1171 } 1172 1173 } else 1174 err = can_rx_register(NULL, op->can_id, 1175 REGMASK(op->can_id), 1176 bcm_rx_handler, op, "bcm"); 1177 if (err) { 1178 /* this bcm rx op is broken -> remove it */ 1179 list_del(&op->list); 1180 bcm_remove_op(op); 1181 return err; 1182 } 1183 } 1184 1185 return msg_head->nframes * CFSIZ + MHSIZ; 1186 } 1187 1188 /* 1189 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg) 1190 */ 1191 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk) 1192 { 1193 struct sk_buff *skb; 1194 struct net_device *dev; 1195 int err; 1196 1197 /* we need a real device to send frames */ 1198 if (!ifindex) 1199 return -ENODEV; 1200 1201 skb = alloc_skb(CFSIZ, GFP_KERNEL); 1202 1203 if (!skb) 1204 return -ENOMEM; 1205 1206 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ); 1207 if (err < 0) { 1208 kfree_skb(skb); 1209 return err; 1210 } 1211 1212 dev = dev_get_by_index(&init_net, ifindex); 1213 if (!dev) { 1214 kfree_skb(skb); 1215 return -ENODEV; 1216 } 1217 1218 skb->dev = dev; 1219 skb->sk = sk; 1220 err = can_send(skb, 1); /* send with loopback */ 1221 dev_put(dev); 1222 1223 if (err) 1224 return err; 1225 1226 return CFSIZ + MHSIZ; 1227 } 1228 1229 /* 1230 * bcm_sendmsg - process BCM commands (opcodes) from the userspace 1231 */ 1232 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock, 1233 struct msghdr *msg, size_t size) 1234 { 1235 struct sock *sk = sock->sk; 1236 struct bcm_sock *bo = bcm_sk(sk); 1237 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */ 1238 struct bcm_msg_head msg_head; 1239 int ret; /* read bytes or error codes as return value */ 1240 1241 if (!bo->bound) 1242 return -ENOTCONN; 1243 1244 /* check for valid message length from userspace */ 1245 if (size < MHSIZ || (size - MHSIZ) % CFSIZ) 1246 return -EINVAL; 1247 1248 /* check for alternative ifindex for this bcm_op */ 1249 1250 if (!ifindex && msg->msg_name) { 1251 /* no bound device as default => check msg_name */ 1252 struct sockaddr_can *addr = 1253 (struct sockaddr_can *)msg->msg_name; 1254 1255 if (addr->can_family != AF_CAN) 1256 return -EINVAL; 1257 1258 /* ifindex from sendto() */ 1259 ifindex = addr->can_ifindex; 1260 1261 if (ifindex) { 1262 struct net_device *dev; 1263 1264 dev = dev_get_by_index(&init_net, ifindex); 1265 if (!dev) 1266 return -ENODEV; 1267 1268 if (dev->type != ARPHRD_CAN) { 1269 dev_put(dev); 1270 return -ENODEV; 1271 } 1272 1273 dev_put(dev); 1274 } 1275 } 1276 1277 /* read message head information */ 1278 1279 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ); 1280 if (ret < 0) 1281 return ret; 1282 1283 lock_sock(sk); 1284 1285 switch (msg_head.opcode) { 1286 1287 case TX_SETUP: 1288 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk); 1289 break; 1290 1291 case RX_SETUP: 1292 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk); 1293 break; 1294 1295 case TX_DELETE: 1296 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex)) 1297 ret = MHSIZ; 1298 else 1299 ret = -EINVAL; 1300 break; 1301 1302 case RX_DELETE: 1303 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex)) 1304 ret = MHSIZ; 1305 else 1306 ret = -EINVAL; 1307 break; 1308 1309 case TX_READ: 1310 /* reuse msg_head for the reply to TX_READ */ 1311 msg_head.opcode = TX_STATUS; 1312 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex); 1313 break; 1314 1315 case RX_READ: 1316 /* reuse msg_head for the reply to RX_READ */ 1317 msg_head.opcode = RX_STATUS; 1318 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex); 1319 break; 1320 1321 case TX_SEND: 1322 /* we need exactly one can_frame behind the msg head */ 1323 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ)) 1324 ret = -EINVAL; 1325 else 1326 ret = bcm_tx_send(msg, ifindex, sk); 1327 break; 1328 1329 default: 1330 ret = -EINVAL; 1331 break; 1332 } 1333 1334 release_sock(sk); 1335 1336 return ret; 1337 } 1338 1339 /* 1340 * notification handler for netdevice status changes 1341 */ 1342 static int bcm_notifier(struct notifier_block *nb, unsigned long msg, 1343 void *data) 1344 { 1345 struct net_device *dev = (struct net_device *)data; 1346 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier); 1347 struct sock *sk = &bo->sk; 1348 struct bcm_op *op; 1349 int notify_enodev = 0; 1350 1351 if (!net_eq(dev_net(dev), &init_net)) 1352 return NOTIFY_DONE; 1353 1354 if (dev->type != ARPHRD_CAN) 1355 return NOTIFY_DONE; 1356 1357 switch (msg) { 1358 1359 case NETDEV_UNREGISTER: 1360 lock_sock(sk); 1361 1362 /* remove device specific receive entries */ 1363 list_for_each_entry(op, &bo->rx_ops, list) 1364 if (op->rx_reg_dev == dev) 1365 bcm_rx_unreg(dev, op); 1366 1367 /* remove device reference, if this is our bound device */ 1368 if (bo->bound && bo->ifindex == dev->ifindex) { 1369 bo->bound = 0; 1370 bo->ifindex = 0; 1371 notify_enodev = 1; 1372 } 1373 1374 release_sock(sk); 1375 1376 if (notify_enodev) { 1377 sk->sk_err = ENODEV; 1378 if (!sock_flag(sk, SOCK_DEAD)) 1379 sk->sk_error_report(sk); 1380 } 1381 break; 1382 1383 case NETDEV_DOWN: 1384 if (bo->bound && bo->ifindex == dev->ifindex) { 1385 sk->sk_err = ENETDOWN; 1386 if (!sock_flag(sk, SOCK_DEAD)) 1387 sk->sk_error_report(sk); 1388 } 1389 } 1390 1391 return NOTIFY_DONE; 1392 } 1393 1394 /* 1395 * initial settings for all BCM sockets to be set at socket creation time 1396 */ 1397 static int bcm_init(struct sock *sk) 1398 { 1399 struct bcm_sock *bo = bcm_sk(sk); 1400 1401 bo->bound = 0; 1402 bo->ifindex = 0; 1403 bo->dropped_usr_msgs = 0; 1404 bo->bcm_proc_read = NULL; 1405 1406 INIT_LIST_HEAD(&bo->tx_ops); 1407 INIT_LIST_HEAD(&bo->rx_ops); 1408 1409 /* set notifier */ 1410 bo->notifier.notifier_call = bcm_notifier; 1411 1412 register_netdevice_notifier(&bo->notifier); 1413 1414 return 0; 1415 } 1416 1417 /* 1418 * standard socket functions 1419 */ 1420 static int bcm_release(struct socket *sock) 1421 { 1422 struct sock *sk = sock->sk; 1423 struct bcm_sock *bo = bcm_sk(sk); 1424 struct bcm_op *op, *next; 1425 1426 /* remove bcm_ops, timer, rx_unregister(), etc. */ 1427 1428 unregister_netdevice_notifier(&bo->notifier); 1429 1430 lock_sock(sk); 1431 1432 list_for_each_entry_safe(op, next, &bo->tx_ops, list) 1433 bcm_remove_op(op); 1434 1435 list_for_each_entry_safe(op, next, &bo->rx_ops, list) { 1436 /* 1437 * Don't care if we're bound or not (due to netdev problems) 1438 * can_rx_unregister() is always a save thing to do here. 1439 */ 1440 if (op->ifindex) { 1441 /* 1442 * Only remove subscriptions that had not 1443 * been removed due to NETDEV_UNREGISTER 1444 * in bcm_notifier() 1445 */ 1446 if (op->rx_reg_dev) { 1447 struct net_device *dev; 1448 1449 dev = dev_get_by_index(&init_net, op->ifindex); 1450 if (dev) { 1451 bcm_rx_unreg(dev, op); 1452 dev_put(dev); 1453 } 1454 } 1455 } else 1456 can_rx_unregister(NULL, op->can_id, 1457 REGMASK(op->can_id), 1458 bcm_rx_handler, op); 1459 1460 bcm_remove_op(op); 1461 } 1462 1463 /* remove procfs entry */ 1464 if (proc_dir && bo->bcm_proc_read) 1465 remove_proc_entry(bo->procname, proc_dir); 1466 1467 /* remove device reference */ 1468 if (bo->bound) { 1469 bo->bound = 0; 1470 bo->ifindex = 0; 1471 } 1472 1473 sock_orphan(sk); 1474 sock->sk = NULL; 1475 1476 release_sock(sk); 1477 sock_put(sk); 1478 1479 return 0; 1480 } 1481 1482 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len, 1483 int flags) 1484 { 1485 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 1486 struct sock *sk = sock->sk; 1487 struct bcm_sock *bo = bcm_sk(sk); 1488 1489 if (bo->bound) 1490 return -EISCONN; 1491 1492 /* bind a device to this socket */ 1493 if (addr->can_ifindex) { 1494 struct net_device *dev; 1495 1496 dev = dev_get_by_index(&init_net, addr->can_ifindex); 1497 if (!dev) 1498 return -ENODEV; 1499 1500 if (dev->type != ARPHRD_CAN) { 1501 dev_put(dev); 1502 return -ENODEV; 1503 } 1504 1505 bo->ifindex = dev->ifindex; 1506 dev_put(dev); 1507 1508 } else { 1509 /* no interface reference for ifindex = 0 ('any' CAN device) */ 1510 bo->ifindex = 0; 1511 } 1512 1513 bo->bound = 1; 1514 1515 if (proc_dir) { 1516 /* unique socket address as filename */ 1517 sprintf(bo->procname, "%p", sock); 1518 bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644, 1519 proc_dir, 1520 bcm_read_proc, sk); 1521 } 1522 1523 return 0; 1524 } 1525 1526 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock, 1527 struct msghdr *msg, size_t size, int flags) 1528 { 1529 struct sock *sk = sock->sk; 1530 struct sk_buff *skb; 1531 int error = 0; 1532 int noblock; 1533 int err; 1534 1535 noblock = flags & MSG_DONTWAIT; 1536 flags &= ~MSG_DONTWAIT; 1537 skb = skb_recv_datagram(sk, flags, noblock, &error); 1538 if (!skb) 1539 return error; 1540 1541 if (skb->len < size) 1542 size = skb->len; 1543 1544 err = memcpy_toiovec(msg->msg_iov, skb->data, size); 1545 if (err < 0) { 1546 skb_free_datagram(sk, skb); 1547 return err; 1548 } 1549 1550 sock_recv_timestamp(msg, sk, skb); 1551 1552 if (msg->msg_name) { 1553 msg->msg_namelen = sizeof(struct sockaddr_can); 1554 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1555 } 1556 1557 skb_free_datagram(sk, skb); 1558 1559 return size; 1560 } 1561 1562 static struct proto_ops bcm_ops __read_mostly = { 1563 .family = PF_CAN, 1564 .release = bcm_release, 1565 .bind = sock_no_bind, 1566 .connect = bcm_connect, 1567 .socketpair = sock_no_socketpair, 1568 .accept = sock_no_accept, 1569 .getname = sock_no_getname, 1570 .poll = datagram_poll, 1571 .ioctl = NULL, /* use can_ioctl() from af_can.c */ 1572 .listen = sock_no_listen, 1573 .shutdown = sock_no_shutdown, 1574 .setsockopt = sock_no_setsockopt, 1575 .getsockopt = sock_no_getsockopt, 1576 .sendmsg = bcm_sendmsg, 1577 .recvmsg = bcm_recvmsg, 1578 .mmap = sock_no_mmap, 1579 .sendpage = sock_no_sendpage, 1580 }; 1581 1582 static struct proto bcm_proto __read_mostly = { 1583 .name = "CAN_BCM", 1584 .owner = THIS_MODULE, 1585 .obj_size = sizeof(struct bcm_sock), 1586 .init = bcm_init, 1587 }; 1588 1589 static struct can_proto bcm_can_proto __read_mostly = { 1590 .type = SOCK_DGRAM, 1591 .protocol = CAN_BCM, 1592 .capability = -1, 1593 .ops = &bcm_ops, 1594 .prot = &bcm_proto, 1595 }; 1596 1597 static int __init bcm_module_init(void) 1598 { 1599 int err; 1600 1601 printk(banner); 1602 1603 err = can_proto_register(&bcm_can_proto); 1604 if (err < 0) { 1605 printk(KERN_ERR "can: registration of bcm protocol failed\n"); 1606 return err; 1607 } 1608 1609 /* create /proc/net/can-bcm directory */ 1610 proc_dir = proc_mkdir("can-bcm", init_net.proc_net); 1611 return 0; 1612 } 1613 1614 static void __exit bcm_module_exit(void) 1615 { 1616 can_proto_unregister(&bcm_can_proto); 1617 1618 if (proc_dir) 1619 proc_net_remove(&init_net, "can-bcm"); 1620 } 1621 1622 module_init(bcm_module_init); 1623 module_exit(bcm_module_exit); 1624