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