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