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 */ 41 42 #include <linux/module.h> 43 #include <linux/init.h> 44 #include <linux/interrupt.h> 45 #include <linux/hrtimer.h> 46 #include <linux/list.h> 47 #include <linux/proc_fs.h> 48 #include <linux/seq_file.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/skb.h> 58 #include <linux/can/bcm.h> 59 #include <linux/slab.h> 60 #include <net/sock.h> 61 #include <net/net_namespace.h> 62 63 /* 64 * To send multiple CAN frame content within TX_SETUP or to filter 65 * CAN messages with multiplex index within RX_SETUP, the number of 66 * different filters is limited to 256 due to the one byte index value. 67 */ 68 #define MAX_NFRAMES 256 69 70 /* use of last_frames[index].can_dlc */ 71 #define RX_RECV 0x40 /* received data for this element */ 72 #define RX_THR 0x80 /* element not been sent due to throttle feature */ 73 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */ 74 75 /* get best masking value for can_rx_register() for a given single can_id */ 76 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \ 77 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \ 78 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG)) 79 80 #define CAN_BCM_VERSION CAN_VERSION 81 82 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol"); 83 MODULE_LICENSE("Dual BSD/GPL"); 84 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); 85 MODULE_ALIAS("can-proto-2"); 86 87 /* easy access to can_frame payload */ 88 static inline u64 GET_U64(const struct can_frame *cp) 89 { 90 return *(u64 *)cp->data; 91 } 92 93 struct bcm_op { 94 struct list_head list; 95 int ifindex; 96 canid_t can_id; 97 u32 flags; 98 unsigned long frames_abs, frames_filtered; 99 struct bcm_timeval ival1, ival2; 100 struct hrtimer timer, thrtimer; 101 struct tasklet_struct tsklet, thrtsklet; 102 ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg; 103 int rx_ifindex; 104 u32 count; 105 u32 nframes; 106 u32 currframe; 107 struct can_frame *frames; 108 struct can_frame *last_frames; 109 struct can_frame sframe; 110 struct can_frame last_sframe; 111 struct sock *sk; 112 struct net_device *rx_reg_dev; 113 }; 114 115 static struct proc_dir_entry *proc_dir; 116 117 struct bcm_sock { 118 struct sock sk; 119 int bound; 120 int ifindex; 121 struct notifier_block notifier; 122 struct list_head rx_ops; 123 struct list_head tx_ops; 124 unsigned long dropped_usr_msgs; 125 struct proc_dir_entry *bcm_proc_read; 126 char procname [32]; /* inode number in decimal with \0 */ 127 }; 128 129 static inline struct bcm_sock *bcm_sk(const struct sock *sk) 130 { 131 return (struct bcm_sock *)sk; 132 } 133 134 static inline ktime_t bcm_timeval_to_ktime(struct bcm_timeval tv) 135 { 136 return ktime_set(tv.tv_sec, tv.tv_usec * NSEC_PER_USEC); 137 } 138 139 #define CFSIZ sizeof(struct can_frame) 140 #define OPSIZ sizeof(struct bcm_op) 141 #define MHSIZ sizeof(struct bcm_msg_head) 142 143 /* 144 * procfs functions 145 */ 146 static char *bcm_proc_getifname(char *result, int ifindex) 147 { 148 struct net_device *dev; 149 150 if (!ifindex) 151 return "any"; 152 153 rcu_read_lock(); 154 dev = dev_get_by_index_rcu(&init_net, ifindex); 155 if (dev) 156 strcpy(result, dev->name); 157 else 158 strcpy(result, "???"); 159 rcu_read_unlock(); 160 161 return result; 162 } 163 164 static int bcm_proc_show(struct seq_file *m, void *v) 165 { 166 char ifname[IFNAMSIZ]; 167 struct sock *sk = (struct sock *)m->private; 168 struct bcm_sock *bo = bcm_sk(sk); 169 struct bcm_op *op; 170 171 seq_printf(m, ">>> socket %pK", sk->sk_socket); 172 seq_printf(m, " / sk %pK", sk); 173 seq_printf(m, " / bo %pK", bo); 174 seq_printf(m, " / dropped %lu", bo->dropped_usr_msgs); 175 seq_printf(m, " / bound %s", bcm_proc_getifname(ifname, bo->ifindex)); 176 seq_printf(m, " <<<\n"); 177 178 list_for_each_entry(op, &bo->rx_ops, list) { 179 180 unsigned long reduction; 181 182 /* print only active entries & prevent division by zero */ 183 if (!op->frames_abs) 184 continue; 185 186 seq_printf(m, "rx_op: %03X %-5s ", 187 op->can_id, bcm_proc_getifname(ifname, op->ifindex)); 188 seq_printf(m, "[%u]%c ", op->nframes, 189 (op->flags & RX_CHECK_DLC)?'d':' '); 190 if (op->kt_ival1.tv64) 191 seq_printf(m, "timeo=%lld ", 192 (long long) 193 ktime_to_us(op->kt_ival1)); 194 195 if (op->kt_ival2.tv64) 196 seq_printf(m, "thr=%lld ", 197 (long long) 198 ktime_to_us(op->kt_ival2)); 199 200 seq_printf(m, "# recv %ld (%ld) => reduction: ", 201 op->frames_filtered, op->frames_abs); 202 203 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs; 204 205 seq_printf(m, "%s%ld%%\n", 206 (reduction == 100)?"near ":"", reduction); 207 } 208 209 list_for_each_entry(op, &bo->tx_ops, list) { 210 211 seq_printf(m, "tx_op: %03X %s [%u] ", 212 op->can_id, 213 bcm_proc_getifname(ifname, op->ifindex), 214 op->nframes); 215 216 if (op->kt_ival1.tv64) 217 seq_printf(m, "t1=%lld ", 218 (long long) ktime_to_us(op->kt_ival1)); 219 220 if (op->kt_ival2.tv64) 221 seq_printf(m, "t2=%lld ", 222 (long long) ktime_to_us(op->kt_ival2)); 223 224 seq_printf(m, "# sent %ld\n", op->frames_abs); 225 } 226 seq_putc(m, '\n'); 227 return 0; 228 } 229 230 static int bcm_proc_open(struct inode *inode, struct file *file) 231 { 232 return single_open(file, bcm_proc_show, PDE_DATA(inode)); 233 } 234 235 static const struct file_operations bcm_proc_fops = { 236 .owner = THIS_MODULE, 237 .open = bcm_proc_open, 238 .read = seq_read, 239 .llseek = seq_lseek, 240 .release = single_release, 241 }; 242 243 /* 244 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface 245 * of the given bcm tx op 246 */ 247 static void bcm_can_tx(struct bcm_op *op) 248 { 249 struct sk_buff *skb; 250 struct net_device *dev; 251 struct can_frame *cf = &op->frames[op->currframe]; 252 253 /* no target device? => exit */ 254 if (!op->ifindex) 255 return; 256 257 dev = dev_get_by_index(&init_net, op->ifindex); 258 if (!dev) { 259 /* RFC: should this bcm_op remove itself here? */ 260 return; 261 } 262 263 skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), gfp_any()); 264 if (!skb) 265 goto out; 266 267 can_skb_reserve(skb); 268 can_skb_prv(skb)->ifindex = dev->ifindex; 269 can_skb_prv(skb)->skbcnt = 0; 270 271 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ); 272 273 /* send with loopback */ 274 skb->dev = dev; 275 can_skb_set_owner(skb, op->sk); 276 can_send(skb, 1); 277 278 /* update statistics */ 279 op->currframe++; 280 op->frames_abs++; 281 282 /* reached last frame? */ 283 if (op->currframe >= op->nframes) 284 op->currframe = 0; 285 out: 286 dev_put(dev); 287 } 288 289 /* 290 * bcm_send_to_user - send a BCM message to the userspace 291 * (consisting of bcm_msg_head + x CAN frames) 292 */ 293 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, 294 struct can_frame *frames, int has_timestamp) 295 { 296 struct sk_buff *skb; 297 struct can_frame *firstframe; 298 struct sockaddr_can *addr; 299 struct sock *sk = op->sk; 300 unsigned int datalen = head->nframes * CFSIZ; 301 int err; 302 303 skb = alloc_skb(sizeof(*head) + datalen, gfp_any()); 304 if (!skb) 305 return; 306 307 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head)); 308 309 if (head->nframes) { 310 /* can_frames starting here */ 311 firstframe = (struct can_frame *)skb_tail_pointer(skb); 312 313 memcpy(skb_put(skb, datalen), frames, datalen); 314 315 /* 316 * the BCM uses the can_dlc-element of the can_frame 317 * structure for internal purposes. This is only 318 * relevant for updates that are generated by the 319 * BCM, where nframes is 1 320 */ 321 if (head->nframes == 1) 322 firstframe->can_dlc &= BCM_CAN_DLC_MASK; 323 } 324 325 if (has_timestamp) { 326 /* restore rx timestamp */ 327 skb->tstamp = op->rx_stamp; 328 } 329 330 /* 331 * Put the datagram to the queue so that bcm_recvmsg() can 332 * get it from there. We need to pass the interface index to 333 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb 334 * containing the interface index. 335 */ 336 337 sock_skb_cb_check_size(sizeof(struct sockaddr_can)); 338 addr = (struct sockaddr_can *)skb->cb; 339 memset(addr, 0, sizeof(*addr)); 340 addr->can_family = AF_CAN; 341 addr->can_ifindex = op->rx_ifindex; 342 343 err = sock_queue_rcv_skb(sk, skb); 344 if (err < 0) { 345 struct bcm_sock *bo = bcm_sk(sk); 346 347 kfree_skb(skb); 348 /* don't care about overflows in this statistic */ 349 bo->dropped_usr_msgs++; 350 } 351 } 352 353 static void bcm_tx_start_timer(struct bcm_op *op) 354 { 355 if (op->kt_ival1.tv64 && op->count) 356 hrtimer_start(&op->timer, 357 ktime_add(ktime_get(), op->kt_ival1), 358 HRTIMER_MODE_ABS); 359 else if (op->kt_ival2.tv64) 360 hrtimer_start(&op->timer, 361 ktime_add(ktime_get(), op->kt_ival2), 362 HRTIMER_MODE_ABS); 363 } 364 365 static void bcm_tx_timeout_tsklet(unsigned long data) 366 { 367 struct bcm_op *op = (struct bcm_op *)data; 368 struct bcm_msg_head msg_head; 369 370 if (op->kt_ival1.tv64 && (op->count > 0)) { 371 372 op->count--; 373 if (!op->count && (op->flags & TX_COUNTEVT)) { 374 375 /* create notification to user */ 376 msg_head.opcode = TX_EXPIRED; 377 msg_head.flags = op->flags; 378 msg_head.count = op->count; 379 msg_head.ival1 = op->ival1; 380 msg_head.ival2 = op->ival2; 381 msg_head.can_id = op->can_id; 382 msg_head.nframes = 0; 383 384 bcm_send_to_user(op, &msg_head, NULL, 0); 385 } 386 bcm_can_tx(op); 387 388 } else if (op->kt_ival2.tv64) 389 bcm_can_tx(op); 390 391 bcm_tx_start_timer(op); 392 } 393 394 /* 395 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions 396 */ 397 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer) 398 { 399 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 400 401 tasklet_schedule(&op->tsklet); 402 403 return HRTIMER_NORESTART; 404 } 405 406 /* 407 * bcm_rx_changed - create a RX_CHANGED notification due to changed content 408 */ 409 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data) 410 { 411 struct bcm_msg_head head; 412 413 /* update statistics */ 414 op->frames_filtered++; 415 416 /* prevent statistics overflow */ 417 if (op->frames_filtered > ULONG_MAX/100) 418 op->frames_filtered = op->frames_abs = 0; 419 420 /* this element is not throttled anymore */ 421 data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV); 422 423 head.opcode = RX_CHANGED; 424 head.flags = op->flags; 425 head.count = op->count; 426 head.ival1 = op->ival1; 427 head.ival2 = op->ival2; 428 head.can_id = op->can_id; 429 head.nframes = 1; 430 431 bcm_send_to_user(op, &head, data, 1); 432 } 433 434 /* 435 * bcm_rx_update_and_send - process a detected relevant receive content change 436 * 1. update the last received data 437 * 2. send a notification to the user (if possible) 438 */ 439 static void bcm_rx_update_and_send(struct bcm_op *op, 440 struct can_frame *lastdata, 441 const struct can_frame *rxdata) 442 { 443 memcpy(lastdata, rxdata, CFSIZ); 444 445 /* mark as used and throttled by default */ 446 lastdata->can_dlc |= (RX_RECV|RX_THR); 447 448 /* throttling mode inactive ? */ 449 if (!op->kt_ival2.tv64) { 450 /* send RX_CHANGED to the user immediately */ 451 bcm_rx_changed(op, lastdata); 452 return; 453 } 454 455 /* with active throttling timer we are just done here */ 456 if (hrtimer_active(&op->thrtimer)) 457 return; 458 459 /* first reception with enabled throttling mode */ 460 if (!op->kt_lastmsg.tv64) 461 goto rx_changed_settime; 462 463 /* got a second frame inside a potential throttle period? */ 464 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) < 465 ktime_to_us(op->kt_ival2)) { 466 /* do not send the saved data - only start throttle timer */ 467 hrtimer_start(&op->thrtimer, 468 ktime_add(op->kt_lastmsg, op->kt_ival2), 469 HRTIMER_MODE_ABS); 470 return; 471 } 472 473 /* the gap was that big, that throttling was not needed here */ 474 rx_changed_settime: 475 bcm_rx_changed(op, lastdata); 476 op->kt_lastmsg = ktime_get(); 477 } 478 479 /* 480 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly 481 * received data stored in op->last_frames[] 482 */ 483 static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index, 484 const struct can_frame *rxdata) 485 { 486 /* 487 * no one uses the MSBs of can_dlc for comparison, 488 * so we use it here to detect the first time of reception 489 */ 490 491 if (!(op->last_frames[index].can_dlc & RX_RECV)) { 492 /* received data for the first time => send update to user */ 493 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 494 return; 495 } 496 497 /* do a real check in can_frame data section */ 498 499 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) != 500 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) { 501 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 502 return; 503 } 504 505 if (op->flags & RX_CHECK_DLC) { 506 /* do a real check in can_frame dlc */ 507 if (rxdata->can_dlc != (op->last_frames[index].can_dlc & 508 BCM_CAN_DLC_MASK)) { 509 bcm_rx_update_and_send(op, &op->last_frames[index], 510 rxdata); 511 return; 512 } 513 } 514 } 515 516 /* 517 * bcm_rx_starttimer - enable timeout monitoring for CAN frame reception 518 */ 519 static void bcm_rx_starttimer(struct bcm_op *op) 520 { 521 if (op->flags & RX_NO_AUTOTIMER) 522 return; 523 524 if (op->kt_ival1.tv64) 525 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL); 526 } 527 528 static void bcm_rx_timeout_tsklet(unsigned long data) 529 { 530 struct bcm_op *op = (struct bcm_op *)data; 531 struct bcm_msg_head msg_head; 532 533 /* create notification to user */ 534 msg_head.opcode = RX_TIMEOUT; 535 msg_head.flags = op->flags; 536 msg_head.count = op->count; 537 msg_head.ival1 = op->ival1; 538 msg_head.ival2 = op->ival2; 539 msg_head.can_id = op->can_id; 540 msg_head.nframes = 0; 541 542 bcm_send_to_user(op, &msg_head, NULL, 0); 543 } 544 545 /* 546 * bcm_rx_timeout_handler - when the (cyclic) CAN frame reception timed out 547 */ 548 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer) 549 { 550 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 551 552 /* schedule before NET_RX_SOFTIRQ */ 553 tasklet_hi_schedule(&op->tsklet); 554 555 /* no restart of the timer is done here! */ 556 557 /* if user wants to be informed, when cyclic CAN-Messages come back */ 558 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) { 559 /* clear received can_frames to indicate 'nothing received' */ 560 memset(op->last_frames, 0, op->nframes * CFSIZ); 561 } 562 563 return HRTIMER_NORESTART; 564 } 565 566 /* 567 * bcm_rx_do_flush - helper for bcm_rx_thr_flush 568 */ 569 static inline int bcm_rx_do_flush(struct bcm_op *op, int update, 570 unsigned int index) 571 { 572 if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) { 573 if (update) 574 bcm_rx_changed(op, &op->last_frames[index]); 575 return 1; 576 } 577 return 0; 578 } 579 580 /* 581 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace 582 * 583 * update == 0 : just check if throttled data is available (any irq context) 584 * update == 1 : check and send throttled data to userspace (soft_irq context) 585 */ 586 static int bcm_rx_thr_flush(struct bcm_op *op, int update) 587 { 588 int updated = 0; 589 590 if (op->nframes > 1) { 591 unsigned int i; 592 593 /* for MUX filter we start at index 1 */ 594 for (i = 1; i < op->nframes; i++) 595 updated += bcm_rx_do_flush(op, update, i); 596 597 } else { 598 /* for RX_FILTER_ID and simple filter */ 599 updated += bcm_rx_do_flush(op, update, 0); 600 } 601 602 return updated; 603 } 604 605 static void bcm_rx_thr_tsklet(unsigned long data) 606 { 607 struct bcm_op *op = (struct bcm_op *)data; 608 609 /* push the changed data to the userspace */ 610 bcm_rx_thr_flush(op, 1); 611 } 612 613 /* 614 * bcm_rx_thr_handler - the time for blocked content updates is over now: 615 * Check for throttled data and send it to the userspace 616 */ 617 static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer) 618 { 619 struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer); 620 621 tasklet_schedule(&op->thrtsklet); 622 623 if (bcm_rx_thr_flush(op, 0)) { 624 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2); 625 return HRTIMER_RESTART; 626 } else { 627 /* rearm throttle handling */ 628 op->kt_lastmsg = ktime_set(0, 0); 629 return HRTIMER_NORESTART; 630 } 631 } 632 633 /* 634 * bcm_rx_handler - handle a CAN frame reception 635 */ 636 static void bcm_rx_handler(struct sk_buff *skb, void *data) 637 { 638 struct bcm_op *op = (struct bcm_op *)data; 639 const struct can_frame *rxframe = (struct can_frame *)skb->data; 640 unsigned int i; 641 642 /* disable timeout */ 643 hrtimer_cancel(&op->timer); 644 645 if (op->can_id != rxframe->can_id) 646 return; 647 648 /* save rx timestamp */ 649 op->rx_stamp = skb->tstamp; 650 /* save originator for recvfrom() */ 651 op->rx_ifindex = skb->dev->ifindex; 652 /* update statistics */ 653 op->frames_abs++; 654 655 if (op->flags & RX_RTR_FRAME) { 656 /* send reply for RTR-request (placed in op->frames[0]) */ 657 bcm_can_tx(op); 658 return; 659 } 660 661 if (op->flags & RX_FILTER_ID) { 662 /* the easiest case */ 663 bcm_rx_update_and_send(op, &op->last_frames[0], rxframe); 664 goto rx_starttimer; 665 } 666 667 if (op->nframes == 1) { 668 /* simple compare with index 0 */ 669 bcm_rx_cmp_to_index(op, 0, rxframe); 670 goto rx_starttimer; 671 } 672 673 if (op->nframes > 1) { 674 /* 675 * multiplex compare 676 * 677 * find the first multiplex mask that fits. 678 * Remark: The MUX-mask is stored in index 0 679 */ 680 681 for (i = 1; i < op->nframes; i++) { 682 if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) == 683 (GET_U64(&op->frames[0]) & 684 GET_U64(&op->frames[i]))) { 685 bcm_rx_cmp_to_index(op, i, rxframe); 686 break; 687 } 688 } 689 } 690 691 rx_starttimer: 692 bcm_rx_starttimer(op); 693 } 694 695 /* 696 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements 697 */ 698 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id, 699 int ifindex) 700 { 701 struct bcm_op *op; 702 703 list_for_each_entry(op, ops, list) { 704 if ((op->can_id == can_id) && (op->ifindex == ifindex)) 705 return op; 706 } 707 708 return NULL; 709 } 710 711 static void bcm_remove_op(struct bcm_op *op) 712 { 713 hrtimer_cancel(&op->timer); 714 hrtimer_cancel(&op->thrtimer); 715 716 if (op->tsklet.func) 717 tasklet_kill(&op->tsklet); 718 719 if (op->thrtsklet.func) 720 tasklet_kill(&op->thrtsklet); 721 722 if ((op->frames) && (op->frames != &op->sframe)) 723 kfree(op->frames); 724 725 if ((op->last_frames) && (op->last_frames != &op->last_sframe)) 726 kfree(op->last_frames); 727 728 kfree(op); 729 } 730 731 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op) 732 { 733 if (op->rx_reg_dev == dev) { 734 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id), 735 bcm_rx_handler, op); 736 737 /* mark as removed subscription */ 738 op->rx_reg_dev = NULL; 739 } else 740 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device " 741 "mismatch %p %p\n", op->rx_reg_dev, dev); 742 } 743 744 /* 745 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops) 746 */ 747 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex) 748 { 749 struct bcm_op *op, *n; 750 751 list_for_each_entry_safe(op, n, ops, list) { 752 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 753 754 /* 755 * Don't care if we're bound or not (due to netdev 756 * problems) can_rx_unregister() is always a save 757 * thing to do here. 758 */ 759 if (op->ifindex) { 760 /* 761 * Only remove subscriptions that had not 762 * been removed due to NETDEV_UNREGISTER 763 * in bcm_notifier() 764 */ 765 if (op->rx_reg_dev) { 766 struct net_device *dev; 767 768 dev = dev_get_by_index(&init_net, 769 op->ifindex); 770 if (dev) { 771 bcm_rx_unreg(dev, op); 772 dev_put(dev); 773 } 774 } 775 } else 776 can_rx_unregister(NULL, op->can_id, 777 REGMASK(op->can_id), 778 bcm_rx_handler, op); 779 780 list_del(&op->list); 781 bcm_remove_op(op); 782 return 1; /* done */ 783 } 784 } 785 786 return 0; /* not found */ 787 } 788 789 /* 790 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops) 791 */ 792 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex) 793 { 794 struct bcm_op *op, *n; 795 796 list_for_each_entry_safe(op, n, ops, list) { 797 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 798 list_del(&op->list); 799 bcm_remove_op(op); 800 return 1; /* done */ 801 } 802 } 803 804 return 0; /* not found */ 805 } 806 807 /* 808 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg) 809 */ 810 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head, 811 int ifindex) 812 { 813 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex); 814 815 if (!op) 816 return -EINVAL; 817 818 /* put current values into msg_head */ 819 msg_head->flags = op->flags; 820 msg_head->count = op->count; 821 msg_head->ival1 = op->ival1; 822 msg_head->ival2 = op->ival2; 823 msg_head->nframes = op->nframes; 824 825 bcm_send_to_user(op, msg_head, op->frames, 0); 826 827 return MHSIZ; 828 } 829 830 /* 831 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg) 832 */ 833 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 834 int ifindex, struct sock *sk) 835 { 836 struct bcm_sock *bo = bcm_sk(sk); 837 struct bcm_op *op; 838 unsigned int i; 839 int err; 840 841 /* we need a real device to send frames */ 842 if (!ifindex) 843 return -ENODEV; 844 845 /* check nframes boundaries - we need at least one can_frame */ 846 if (msg_head->nframes < 1 || msg_head->nframes > MAX_NFRAMES) 847 return -EINVAL; 848 849 /* check the given can_id */ 850 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex); 851 852 if (op) { 853 /* update existing BCM operation */ 854 855 /* 856 * Do we need more space for the can_frames than currently 857 * allocated? -> This is a _really_ unusual use-case and 858 * therefore (complexity / locking) it is not supported. 859 */ 860 if (msg_head->nframes > op->nframes) 861 return -E2BIG; 862 863 /* update can_frames content */ 864 for (i = 0; i < msg_head->nframes; i++) { 865 err = memcpy_from_msg((u8 *)&op->frames[i], msg, CFSIZ); 866 867 if (op->frames[i].can_dlc > 8) 868 err = -EINVAL; 869 870 if (err < 0) 871 return err; 872 873 if (msg_head->flags & TX_CP_CAN_ID) { 874 /* copy can_id into frame */ 875 op->frames[i].can_id = msg_head->can_id; 876 } 877 } 878 879 } else { 880 /* insert new BCM operation for the given can_id */ 881 882 op = kzalloc(OPSIZ, GFP_KERNEL); 883 if (!op) 884 return -ENOMEM; 885 886 op->can_id = msg_head->can_id; 887 888 /* create array for can_frames and copy the data */ 889 if (msg_head->nframes > 1) { 890 op->frames = kmalloc(msg_head->nframes * CFSIZ, 891 GFP_KERNEL); 892 if (!op->frames) { 893 kfree(op); 894 return -ENOMEM; 895 } 896 } else 897 op->frames = &op->sframe; 898 899 for (i = 0; i < msg_head->nframes; i++) { 900 err = memcpy_from_msg((u8 *)&op->frames[i], msg, CFSIZ); 901 902 if (op->frames[i].can_dlc > 8) 903 err = -EINVAL; 904 905 if (err < 0) { 906 if (op->frames != &op->sframe) 907 kfree(op->frames); 908 kfree(op); 909 return err; 910 } 911 912 if (msg_head->flags & TX_CP_CAN_ID) { 913 /* copy can_id into frame */ 914 op->frames[i].can_id = msg_head->can_id; 915 } 916 } 917 918 /* tx_ops never compare with previous received messages */ 919 op->last_frames = NULL; 920 921 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 922 op->sk = sk; 923 op->ifindex = ifindex; 924 925 /* initialize uninitialized (kzalloc) structure */ 926 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 927 op->timer.function = bcm_tx_timeout_handler; 928 929 /* initialize tasklet for tx countevent notification */ 930 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet, 931 (unsigned long) op); 932 933 /* currently unused in tx_ops */ 934 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 935 936 /* add this bcm_op to the list of the tx_ops */ 937 list_add(&op->list, &bo->tx_ops); 938 939 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */ 940 941 if (op->nframes != msg_head->nframes) { 942 op->nframes = msg_head->nframes; 943 /* start multiple frame transmission with index 0 */ 944 op->currframe = 0; 945 } 946 947 /* check flags */ 948 949 op->flags = msg_head->flags; 950 951 if (op->flags & TX_RESET_MULTI_IDX) { 952 /* start multiple frame transmission with index 0 */ 953 op->currframe = 0; 954 } 955 956 if (op->flags & SETTIMER) { 957 /* set timer values */ 958 op->count = msg_head->count; 959 op->ival1 = msg_head->ival1; 960 op->ival2 = msg_head->ival2; 961 op->kt_ival1 = bcm_timeval_to_ktime(msg_head->ival1); 962 op->kt_ival2 = bcm_timeval_to_ktime(msg_head->ival2); 963 964 /* disable an active timer due to zero values? */ 965 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64) 966 hrtimer_cancel(&op->timer); 967 } 968 969 if (op->flags & STARTTIMER) { 970 hrtimer_cancel(&op->timer); 971 /* spec: send can_frame when starting timer */ 972 op->flags |= TX_ANNOUNCE; 973 } 974 975 if (op->flags & TX_ANNOUNCE) { 976 bcm_can_tx(op); 977 if (op->count) 978 op->count--; 979 } 980 981 if (op->flags & STARTTIMER) 982 bcm_tx_start_timer(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 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */ 1006 if (msg_head->nframes > MAX_NFRAMES + 1) 1007 return -EINVAL; 1008 1009 if ((msg_head->flags & RX_RTR_FRAME) && 1010 ((msg_head->nframes != 1) || 1011 (!(msg_head->can_id & CAN_RTR_FLAG)))) 1012 return -EINVAL; 1013 1014 /* check the given can_id */ 1015 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex); 1016 if (op) { 1017 /* update existing BCM operation */ 1018 1019 /* 1020 * Do we need more space for the can_frames than currently 1021 * allocated? -> This is a _really_ unusual use-case and 1022 * therefore (complexity / locking) it is not supported. 1023 */ 1024 if (msg_head->nframes > op->nframes) 1025 return -E2BIG; 1026 1027 if (msg_head->nframes) { 1028 /* update can_frames content */ 1029 err = memcpy_from_msg((u8 *)op->frames, msg, 1030 msg_head->nframes * CFSIZ); 1031 if (err < 0) 1032 return err; 1033 1034 /* clear last_frames to indicate 'nothing received' */ 1035 memset(op->last_frames, 0, msg_head->nframes * CFSIZ); 1036 } 1037 1038 op->nframes = msg_head->nframes; 1039 1040 /* Only an update -> do not call can_rx_register() */ 1041 do_rx_register = 0; 1042 1043 } else { 1044 /* insert new BCM operation for the given can_id */ 1045 op = kzalloc(OPSIZ, GFP_KERNEL); 1046 if (!op) 1047 return -ENOMEM; 1048 1049 op->can_id = msg_head->can_id; 1050 op->nframes = msg_head->nframes; 1051 1052 if (msg_head->nframes > 1) { 1053 /* create array for can_frames and copy the data */ 1054 op->frames = kmalloc(msg_head->nframes * CFSIZ, 1055 GFP_KERNEL); 1056 if (!op->frames) { 1057 kfree(op); 1058 return -ENOMEM; 1059 } 1060 1061 /* create and init array for received can_frames */ 1062 op->last_frames = kzalloc(msg_head->nframes * CFSIZ, 1063 GFP_KERNEL); 1064 if (!op->last_frames) { 1065 kfree(op->frames); 1066 kfree(op); 1067 return -ENOMEM; 1068 } 1069 1070 } else { 1071 op->frames = &op->sframe; 1072 op->last_frames = &op->last_sframe; 1073 } 1074 1075 if (msg_head->nframes) { 1076 err = memcpy_from_msg((u8 *)op->frames, msg, 1077 msg_head->nframes * CFSIZ); 1078 if (err < 0) { 1079 if (op->frames != &op->sframe) 1080 kfree(op->frames); 1081 if (op->last_frames != &op->last_sframe) 1082 kfree(op->last_frames); 1083 kfree(op); 1084 return err; 1085 } 1086 } 1087 1088 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 1089 op->sk = sk; 1090 op->ifindex = ifindex; 1091 1092 /* ifindex for timeout events w/o previous frame reception */ 1093 op->rx_ifindex = ifindex; 1094 1095 /* initialize uninitialized (kzalloc) structure */ 1096 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1097 op->timer.function = bcm_rx_timeout_handler; 1098 1099 /* initialize tasklet for rx timeout notification */ 1100 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet, 1101 (unsigned long) op); 1102 1103 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1104 op->thrtimer.function = bcm_rx_thr_handler; 1105 1106 /* initialize tasklet for rx throttle handling */ 1107 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet, 1108 (unsigned long) op); 1109 1110 /* add this bcm_op to the list of the rx_ops */ 1111 list_add(&op->list, &bo->rx_ops); 1112 1113 /* call can_rx_register() */ 1114 do_rx_register = 1; 1115 1116 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */ 1117 1118 /* check flags */ 1119 op->flags = msg_head->flags; 1120 1121 if (op->flags & RX_RTR_FRAME) { 1122 1123 /* no timers in RTR-mode */ 1124 hrtimer_cancel(&op->thrtimer); 1125 hrtimer_cancel(&op->timer); 1126 1127 /* 1128 * funny feature in RX(!)_SETUP only for RTR-mode: 1129 * copy can_id into frame BUT without RTR-flag to 1130 * prevent a full-load-loopback-test ... ;-] 1131 */ 1132 if ((op->flags & TX_CP_CAN_ID) || 1133 (op->frames[0].can_id == op->can_id)) 1134 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG; 1135 1136 } else { 1137 if (op->flags & SETTIMER) { 1138 1139 /* set timer value */ 1140 op->ival1 = msg_head->ival1; 1141 op->ival2 = msg_head->ival2; 1142 op->kt_ival1 = bcm_timeval_to_ktime(msg_head->ival1); 1143 op->kt_ival2 = bcm_timeval_to_ktime(msg_head->ival2); 1144 1145 /* disable an active timer due to zero value? */ 1146 if (!op->kt_ival1.tv64) 1147 hrtimer_cancel(&op->timer); 1148 1149 /* 1150 * In any case cancel the throttle timer, flush 1151 * potentially blocked msgs and reset throttle handling 1152 */ 1153 op->kt_lastmsg = ktime_set(0, 0); 1154 hrtimer_cancel(&op->thrtimer); 1155 bcm_rx_thr_flush(op, 1); 1156 } 1157 1158 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64) 1159 hrtimer_start(&op->timer, op->kt_ival1, 1160 HRTIMER_MODE_REL); 1161 } 1162 1163 /* now we can register for can_ids, if we added a new bcm_op */ 1164 if (do_rx_register) { 1165 if (ifindex) { 1166 struct net_device *dev; 1167 1168 dev = dev_get_by_index(&init_net, ifindex); 1169 if (dev) { 1170 err = can_rx_register(dev, op->can_id, 1171 REGMASK(op->can_id), 1172 bcm_rx_handler, op, 1173 "bcm"); 1174 1175 op->rx_reg_dev = dev; 1176 dev_put(dev); 1177 } 1178 1179 } else 1180 err = can_rx_register(NULL, op->can_id, 1181 REGMASK(op->can_id), 1182 bcm_rx_handler, op, "bcm"); 1183 if (err) { 1184 /* this bcm rx op is broken -> remove it */ 1185 list_del(&op->list); 1186 bcm_remove_op(op); 1187 return err; 1188 } 1189 } 1190 1191 return msg_head->nframes * CFSIZ + MHSIZ; 1192 } 1193 1194 /* 1195 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg) 1196 */ 1197 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk) 1198 { 1199 struct sk_buff *skb; 1200 struct net_device *dev; 1201 int err; 1202 1203 /* we need a real device to send frames */ 1204 if (!ifindex) 1205 return -ENODEV; 1206 1207 skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), GFP_KERNEL); 1208 if (!skb) 1209 return -ENOMEM; 1210 1211 can_skb_reserve(skb); 1212 1213 err = memcpy_from_msg(skb_put(skb, CFSIZ), msg, CFSIZ); 1214 if (err < 0) { 1215 kfree_skb(skb); 1216 return err; 1217 } 1218 1219 dev = dev_get_by_index(&init_net, ifindex); 1220 if (!dev) { 1221 kfree_skb(skb); 1222 return -ENODEV; 1223 } 1224 1225 can_skb_prv(skb)->ifindex = dev->ifindex; 1226 can_skb_prv(skb)->skbcnt = 0; 1227 skb->dev = dev; 1228 can_skb_set_owner(skb, sk); 1229 err = can_send(skb, 1); /* send with loopback */ 1230 dev_put(dev); 1231 1232 if (err) 1233 return err; 1234 1235 return CFSIZ + MHSIZ; 1236 } 1237 1238 /* 1239 * bcm_sendmsg - process BCM commands (opcodes) from the userspace 1240 */ 1241 static int bcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 1242 { 1243 struct sock *sk = sock->sk; 1244 struct bcm_sock *bo = bcm_sk(sk); 1245 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */ 1246 struct bcm_msg_head msg_head; 1247 int ret; /* read bytes or error codes as return value */ 1248 1249 if (!bo->bound) 1250 return -ENOTCONN; 1251 1252 /* check for valid message length from userspace */ 1253 if (size < MHSIZ || (size - MHSIZ) % CFSIZ) 1254 return -EINVAL; 1255 1256 /* check for alternative ifindex for this bcm_op */ 1257 1258 if (!ifindex && msg->msg_name) { 1259 /* no bound device as default => check msg_name */ 1260 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 1261 1262 if (msg->msg_namelen < sizeof(*addr)) 1263 return -EINVAL; 1264 1265 if (addr->can_family != AF_CAN) 1266 return -EINVAL; 1267 1268 /* ifindex from sendto() */ 1269 ifindex = addr->can_ifindex; 1270 1271 if (ifindex) { 1272 struct net_device *dev; 1273 1274 dev = dev_get_by_index(&init_net, ifindex); 1275 if (!dev) 1276 return -ENODEV; 1277 1278 if (dev->type != ARPHRD_CAN) { 1279 dev_put(dev); 1280 return -ENODEV; 1281 } 1282 1283 dev_put(dev); 1284 } 1285 } 1286 1287 /* read message head information */ 1288 1289 ret = memcpy_from_msg((u8 *)&msg_head, msg, MHSIZ); 1290 if (ret < 0) 1291 return ret; 1292 1293 lock_sock(sk); 1294 1295 switch (msg_head.opcode) { 1296 1297 case TX_SETUP: 1298 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk); 1299 break; 1300 1301 case RX_SETUP: 1302 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk); 1303 break; 1304 1305 case TX_DELETE: 1306 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex)) 1307 ret = MHSIZ; 1308 else 1309 ret = -EINVAL; 1310 break; 1311 1312 case RX_DELETE: 1313 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex)) 1314 ret = MHSIZ; 1315 else 1316 ret = -EINVAL; 1317 break; 1318 1319 case TX_READ: 1320 /* reuse msg_head for the reply to TX_READ */ 1321 msg_head.opcode = TX_STATUS; 1322 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex); 1323 break; 1324 1325 case RX_READ: 1326 /* reuse msg_head for the reply to RX_READ */ 1327 msg_head.opcode = RX_STATUS; 1328 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex); 1329 break; 1330 1331 case TX_SEND: 1332 /* we need exactly one can_frame behind the msg head */ 1333 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ)) 1334 ret = -EINVAL; 1335 else 1336 ret = bcm_tx_send(msg, ifindex, sk); 1337 break; 1338 1339 default: 1340 ret = -EINVAL; 1341 break; 1342 } 1343 1344 release_sock(sk); 1345 1346 return ret; 1347 } 1348 1349 /* 1350 * notification handler for netdevice status changes 1351 */ 1352 static int bcm_notifier(struct notifier_block *nb, unsigned long msg, 1353 void *ptr) 1354 { 1355 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1356 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier); 1357 struct sock *sk = &bo->sk; 1358 struct bcm_op *op; 1359 int notify_enodev = 0; 1360 1361 if (!net_eq(dev_net(dev), &init_net)) 1362 return NOTIFY_DONE; 1363 1364 if (dev->type != ARPHRD_CAN) 1365 return NOTIFY_DONE; 1366 1367 switch (msg) { 1368 1369 case NETDEV_UNREGISTER: 1370 lock_sock(sk); 1371 1372 /* remove device specific receive entries */ 1373 list_for_each_entry(op, &bo->rx_ops, list) 1374 if (op->rx_reg_dev == dev) 1375 bcm_rx_unreg(dev, op); 1376 1377 /* remove device reference, if this is our bound device */ 1378 if (bo->bound && bo->ifindex == dev->ifindex) { 1379 bo->bound = 0; 1380 bo->ifindex = 0; 1381 notify_enodev = 1; 1382 } 1383 1384 release_sock(sk); 1385 1386 if (notify_enodev) { 1387 sk->sk_err = ENODEV; 1388 if (!sock_flag(sk, SOCK_DEAD)) 1389 sk->sk_error_report(sk); 1390 } 1391 break; 1392 1393 case NETDEV_DOWN: 1394 if (bo->bound && bo->ifindex == dev->ifindex) { 1395 sk->sk_err = ENETDOWN; 1396 if (!sock_flag(sk, SOCK_DEAD)) 1397 sk->sk_error_report(sk); 1398 } 1399 } 1400 1401 return NOTIFY_DONE; 1402 } 1403 1404 /* 1405 * initial settings for all BCM sockets to be set at socket creation time 1406 */ 1407 static int bcm_init(struct sock *sk) 1408 { 1409 struct bcm_sock *bo = bcm_sk(sk); 1410 1411 bo->bound = 0; 1412 bo->ifindex = 0; 1413 bo->dropped_usr_msgs = 0; 1414 bo->bcm_proc_read = NULL; 1415 1416 INIT_LIST_HEAD(&bo->tx_ops); 1417 INIT_LIST_HEAD(&bo->rx_ops); 1418 1419 /* set notifier */ 1420 bo->notifier.notifier_call = bcm_notifier; 1421 1422 register_netdevice_notifier(&bo->notifier); 1423 1424 return 0; 1425 } 1426 1427 /* 1428 * standard socket functions 1429 */ 1430 static int bcm_release(struct socket *sock) 1431 { 1432 struct sock *sk = sock->sk; 1433 struct bcm_sock *bo; 1434 struct bcm_op *op, *next; 1435 1436 if (sk == NULL) 1437 return 0; 1438 1439 bo = bcm_sk(sk); 1440 1441 /* remove bcm_ops, timer, rx_unregister(), etc. */ 1442 1443 unregister_netdevice_notifier(&bo->notifier); 1444 1445 lock_sock(sk); 1446 1447 list_for_each_entry_safe(op, next, &bo->tx_ops, list) 1448 bcm_remove_op(op); 1449 1450 list_for_each_entry_safe(op, next, &bo->rx_ops, list) { 1451 /* 1452 * Don't care if we're bound or not (due to netdev problems) 1453 * can_rx_unregister() is always a save thing to do here. 1454 */ 1455 if (op->ifindex) { 1456 /* 1457 * Only remove subscriptions that had not 1458 * been removed due to NETDEV_UNREGISTER 1459 * in bcm_notifier() 1460 */ 1461 if (op->rx_reg_dev) { 1462 struct net_device *dev; 1463 1464 dev = dev_get_by_index(&init_net, op->ifindex); 1465 if (dev) { 1466 bcm_rx_unreg(dev, op); 1467 dev_put(dev); 1468 } 1469 } 1470 } else 1471 can_rx_unregister(NULL, op->can_id, 1472 REGMASK(op->can_id), 1473 bcm_rx_handler, op); 1474 1475 bcm_remove_op(op); 1476 } 1477 1478 /* remove procfs entry */ 1479 if (proc_dir && bo->bcm_proc_read) 1480 remove_proc_entry(bo->procname, proc_dir); 1481 1482 /* remove device reference */ 1483 if (bo->bound) { 1484 bo->bound = 0; 1485 bo->ifindex = 0; 1486 } 1487 1488 sock_orphan(sk); 1489 sock->sk = NULL; 1490 1491 release_sock(sk); 1492 sock_put(sk); 1493 1494 return 0; 1495 } 1496 1497 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len, 1498 int flags) 1499 { 1500 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 1501 struct sock *sk = sock->sk; 1502 struct bcm_sock *bo = bcm_sk(sk); 1503 1504 if (len < sizeof(*addr)) 1505 return -EINVAL; 1506 1507 if (bo->bound) 1508 return -EISCONN; 1509 1510 /* bind a device to this socket */ 1511 if (addr->can_ifindex) { 1512 struct net_device *dev; 1513 1514 dev = dev_get_by_index(&init_net, addr->can_ifindex); 1515 if (!dev) 1516 return -ENODEV; 1517 1518 if (dev->type != ARPHRD_CAN) { 1519 dev_put(dev); 1520 return -ENODEV; 1521 } 1522 1523 bo->ifindex = dev->ifindex; 1524 dev_put(dev); 1525 1526 } else { 1527 /* no interface reference for ifindex = 0 ('any' CAN device) */ 1528 bo->ifindex = 0; 1529 } 1530 1531 bo->bound = 1; 1532 1533 if (proc_dir) { 1534 /* unique socket address as filename */ 1535 sprintf(bo->procname, "%lu", sock_i_ino(sk)); 1536 bo->bcm_proc_read = proc_create_data(bo->procname, 0644, 1537 proc_dir, 1538 &bcm_proc_fops, sk); 1539 } 1540 1541 return 0; 1542 } 1543 1544 static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1545 int flags) 1546 { 1547 struct sock *sk = sock->sk; 1548 struct sk_buff *skb; 1549 int error = 0; 1550 int noblock; 1551 int err; 1552 1553 noblock = flags & MSG_DONTWAIT; 1554 flags &= ~MSG_DONTWAIT; 1555 skb = skb_recv_datagram(sk, flags, noblock, &error); 1556 if (!skb) 1557 return error; 1558 1559 if (skb->len < size) 1560 size = skb->len; 1561 1562 err = memcpy_to_msg(msg, skb->data, size); 1563 if (err < 0) { 1564 skb_free_datagram(sk, skb); 1565 return err; 1566 } 1567 1568 sock_recv_ts_and_drops(msg, sk, skb); 1569 1570 if (msg->msg_name) { 1571 __sockaddr_check_size(sizeof(struct sockaddr_can)); 1572 msg->msg_namelen = sizeof(struct sockaddr_can); 1573 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1574 } 1575 1576 skb_free_datagram(sk, skb); 1577 1578 return size; 1579 } 1580 1581 static const struct proto_ops bcm_ops = { 1582 .family = PF_CAN, 1583 .release = bcm_release, 1584 .bind = sock_no_bind, 1585 .connect = bcm_connect, 1586 .socketpair = sock_no_socketpair, 1587 .accept = sock_no_accept, 1588 .getname = sock_no_getname, 1589 .poll = datagram_poll, 1590 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */ 1591 .listen = sock_no_listen, 1592 .shutdown = sock_no_shutdown, 1593 .setsockopt = sock_no_setsockopt, 1594 .getsockopt = sock_no_getsockopt, 1595 .sendmsg = bcm_sendmsg, 1596 .recvmsg = bcm_recvmsg, 1597 .mmap = sock_no_mmap, 1598 .sendpage = sock_no_sendpage, 1599 }; 1600 1601 static struct proto bcm_proto __read_mostly = { 1602 .name = "CAN_BCM", 1603 .owner = THIS_MODULE, 1604 .obj_size = sizeof(struct bcm_sock), 1605 .init = bcm_init, 1606 }; 1607 1608 static const struct can_proto bcm_can_proto = { 1609 .type = SOCK_DGRAM, 1610 .protocol = CAN_BCM, 1611 .ops = &bcm_ops, 1612 .prot = &bcm_proto, 1613 }; 1614 1615 static int __init bcm_module_init(void) 1616 { 1617 int err; 1618 1619 pr_info("can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n"); 1620 1621 err = can_proto_register(&bcm_can_proto); 1622 if (err < 0) { 1623 printk(KERN_ERR "can: registration of bcm protocol failed\n"); 1624 return err; 1625 } 1626 1627 /* create /proc/net/can-bcm directory */ 1628 proc_dir = proc_mkdir("can-bcm", init_net.proc_net); 1629 return 0; 1630 } 1631 1632 static void __exit bcm_module_exit(void) 1633 { 1634 can_proto_unregister(&bcm_can_proto); 1635 1636 if (proc_dir) 1637 remove_proc_entry("can-bcm", init_net.proc_net); 1638 } 1639 1640 module_init(bcm_module_init); 1641 module_exit(bcm_module_exit); 1642