1 /* 2 * proc.c - procfs support for Protocol family CAN core module 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/proc_fs.h> 46 #include <linux/list.h> 47 #include <linux/rcupdate.h> 48 #include <linux/can/core.h> 49 50 #include "af_can.h" 51 52 /* 53 * proc filenames for the PF_CAN core 54 */ 55 56 #define CAN_PROC_VERSION "version" 57 #define CAN_PROC_STATS "stats" 58 #define CAN_PROC_RESET_STATS "reset_stats" 59 #define CAN_PROC_RCVLIST_ALL "rcvlist_all" 60 #define CAN_PROC_RCVLIST_FIL "rcvlist_fil" 61 #define CAN_PROC_RCVLIST_INV "rcvlist_inv" 62 #define CAN_PROC_RCVLIST_SFF "rcvlist_sff" 63 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff" 64 #define CAN_PROC_RCVLIST_ERR "rcvlist_err" 65 66 static struct proc_dir_entry *can_dir; 67 static struct proc_dir_entry *pde_version; 68 static struct proc_dir_entry *pde_stats; 69 static struct proc_dir_entry *pde_reset_stats; 70 static struct proc_dir_entry *pde_rcvlist_all; 71 static struct proc_dir_entry *pde_rcvlist_fil; 72 static struct proc_dir_entry *pde_rcvlist_inv; 73 static struct proc_dir_entry *pde_rcvlist_sff; 74 static struct proc_dir_entry *pde_rcvlist_eff; 75 static struct proc_dir_entry *pde_rcvlist_err; 76 77 static int user_reset; 78 79 static const char rx_list_name[][8] = { 80 [RX_ERR] = "rx_err", 81 [RX_ALL] = "rx_all", 82 [RX_FIL] = "rx_fil", 83 [RX_INV] = "rx_inv", 84 [RX_EFF] = "rx_eff", 85 }; 86 87 /* 88 * af_can statistics stuff 89 */ 90 91 static void can_init_stats(void) 92 { 93 /* 94 * This memset function is called from a timer context (when 95 * can_stattimer is active which is the default) OR in a process 96 * context (reading the proc_fs when can_stattimer is disabled). 97 */ 98 memset(&can_stats, 0, sizeof(can_stats)); 99 can_stats.jiffies_init = jiffies; 100 101 can_pstats.stats_reset++; 102 103 if (user_reset) { 104 user_reset = 0; 105 can_pstats.user_reset++; 106 } 107 } 108 109 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif, 110 unsigned long count) 111 { 112 unsigned long rate; 113 114 if (oldjif == newjif) 115 return 0; 116 117 /* see can_stat_update() - this should NEVER happen! */ 118 if (count > (ULONG_MAX / HZ)) { 119 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n", 120 count); 121 return 99999999; 122 } 123 124 rate = (count * HZ) / (newjif - oldjif); 125 126 return rate; 127 } 128 129 void can_stat_update(unsigned long data) 130 { 131 unsigned long j = jiffies; /* snapshot */ 132 133 /* restart counting in timer context on user request */ 134 if (user_reset) 135 can_init_stats(); 136 137 /* restart counting on jiffies overflow */ 138 if (j < can_stats.jiffies_init) 139 can_init_stats(); 140 141 /* prevent overflow in calc_rate() */ 142 if (can_stats.rx_frames > (ULONG_MAX / HZ)) 143 can_init_stats(); 144 145 /* prevent overflow in calc_rate() */ 146 if (can_stats.tx_frames > (ULONG_MAX / HZ)) 147 can_init_stats(); 148 149 /* matches overflow - very improbable */ 150 if (can_stats.matches > (ULONG_MAX / 100)) 151 can_init_stats(); 152 153 /* calc total values */ 154 if (can_stats.rx_frames) 155 can_stats.total_rx_match_ratio = (can_stats.matches * 100) / 156 can_stats.rx_frames; 157 158 can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j, 159 can_stats.tx_frames); 160 can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j, 161 can_stats.rx_frames); 162 163 /* calc current values */ 164 if (can_stats.rx_frames_delta) 165 can_stats.current_rx_match_ratio = 166 (can_stats.matches_delta * 100) / 167 can_stats.rx_frames_delta; 168 169 can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta); 170 can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta); 171 172 /* check / update maximum values */ 173 if (can_stats.max_tx_rate < can_stats.current_tx_rate) 174 can_stats.max_tx_rate = can_stats.current_tx_rate; 175 176 if (can_stats.max_rx_rate < can_stats.current_rx_rate) 177 can_stats.max_rx_rate = can_stats.current_rx_rate; 178 179 if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio) 180 can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio; 181 182 /* clear values for 'current rate' calculation */ 183 can_stats.tx_frames_delta = 0; 184 can_stats.rx_frames_delta = 0; 185 can_stats.matches_delta = 0; 186 187 /* restart timer (one second) */ 188 mod_timer(&can_stattimer, round_jiffies(jiffies + HZ)); 189 } 190 191 /* 192 * proc read functions 193 * 194 * From known use-cases we expect about 10 entries in a receive list to be 195 * printed in the proc_fs. So PAGE_SIZE is definitely enough space here. 196 * 197 */ 198 199 static int can_print_rcvlist(char *page, int len, struct hlist_head *rx_list, 200 struct net_device *dev) 201 { 202 struct receiver *r; 203 struct hlist_node *n; 204 205 rcu_read_lock(); 206 hlist_for_each_entry_rcu(r, n, rx_list, list) { 207 char *fmt = (r->can_id & CAN_EFF_FLAG)? 208 " %-5s %08X %08x %08x %08x %8ld %s\n" : 209 " %-5s %03X %08x %08lx %08lx %8ld %s\n"; 210 211 len += snprintf(page + len, PAGE_SIZE - len, fmt, 212 DNAME(dev), r->can_id, r->mask, 213 (unsigned long)r->func, (unsigned long)r->data, 214 r->matches, r->ident); 215 216 /* does a typical line fit into the current buffer? */ 217 218 /* 100 Bytes before end of buffer */ 219 if (len > PAGE_SIZE - 100) { 220 /* mark output cut off */ 221 len += snprintf(page + len, PAGE_SIZE - len, 222 " (..)\n"); 223 break; 224 } 225 } 226 rcu_read_unlock(); 227 228 return len; 229 } 230 231 static int can_print_recv_banner(char *page, int len) 232 { 233 /* 234 * can1. 00000000 00000000 00000000 235 * ....... 0 tp20 236 */ 237 len += snprintf(page + len, PAGE_SIZE - len, 238 " device can_id can_mask function" 239 " userdata matches ident\n"); 240 241 return len; 242 } 243 244 static int can_proc_read_stats(char *page, char **start, off_t off, 245 int count, int *eof, void *data) 246 { 247 int len = 0; 248 249 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 250 len += snprintf(page + len, PAGE_SIZE - len, 251 " %8ld transmitted frames (TXF)\n", 252 can_stats.tx_frames); 253 len += snprintf(page + len, PAGE_SIZE - len, 254 " %8ld received frames (RXF)\n", can_stats.rx_frames); 255 len += snprintf(page + len, PAGE_SIZE - len, 256 " %8ld matched frames (RXMF)\n", can_stats.matches); 257 258 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 259 260 if (can_stattimer.function == can_stat_update) { 261 len += snprintf(page + len, PAGE_SIZE - len, 262 " %8ld %% total match ratio (RXMR)\n", 263 can_stats.total_rx_match_ratio); 264 265 len += snprintf(page + len, PAGE_SIZE - len, 266 " %8ld frames/s total tx rate (TXR)\n", 267 can_stats.total_tx_rate); 268 len += snprintf(page + len, PAGE_SIZE - len, 269 " %8ld frames/s total rx rate (RXR)\n", 270 can_stats.total_rx_rate); 271 272 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 273 274 len += snprintf(page + len, PAGE_SIZE - len, 275 " %8ld %% current match ratio (CRXMR)\n", 276 can_stats.current_rx_match_ratio); 277 278 len += snprintf(page + len, PAGE_SIZE - len, 279 " %8ld frames/s current tx rate (CTXR)\n", 280 can_stats.current_tx_rate); 281 len += snprintf(page + len, PAGE_SIZE - len, 282 " %8ld frames/s current rx rate (CRXR)\n", 283 can_stats.current_rx_rate); 284 285 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 286 287 len += snprintf(page + len, PAGE_SIZE - len, 288 " %8ld %% max match ratio (MRXMR)\n", 289 can_stats.max_rx_match_ratio); 290 291 len += snprintf(page + len, PAGE_SIZE - len, 292 " %8ld frames/s max tx rate (MTXR)\n", 293 can_stats.max_tx_rate); 294 len += snprintf(page + len, PAGE_SIZE - len, 295 " %8ld frames/s max rx rate (MRXR)\n", 296 can_stats.max_rx_rate); 297 298 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 299 } 300 301 len += snprintf(page + len, PAGE_SIZE - len, 302 " %8ld current receive list entries (CRCV)\n", 303 can_pstats.rcv_entries); 304 len += snprintf(page + len, PAGE_SIZE - len, 305 " %8ld maximum receive list entries (MRCV)\n", 306 can_pstats.rcv_entries_max); 307 308 if (can_pstats.stats_reset) 309 len += snprintf(page + len, PAGE_SIZE - len, 310 "\n %8ld statistic resets (STR)\n", 311 can_pstats.stats_reset); 312 313 if (can_pstats.user_reset) 314 len += snprintf(page + len, PAGE_SIZE - len, 315 " %8ld user statistic resets (USTR)\n", 316 can_pstats.user_reset); 317 318 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 319 320 *eof = 1; 321 return len; 322 } 323 324 static int can_proc_read_reset_stats(char *page, char **start, off_t off, 325 int count, int *eof, void *data) 326 { 327 int len = 0; 328 329 user_reset = 1; 330 331 if (can_stattimer.function == can_stat_update) { 332 len += snprintf(page + len, PAGE_SIZE - len, 333 "Scheduled statistic reset #%ld.\n", 334 can_pstats.stats_reset + 1); 335 336 } else { 337 if (can_stats.jiffies_init != jiffies) 338 can_init_stats(); 339 340 len += snprintf(page + len, PAGE_SIZE - len, 341 "Performed statistic reset #%ld.\n", 342 can_pstats.stats_reset); 343 } 344 345 *eof = 1; 346 return len; 347 } 348 349 static int can_proc_read_version(char *page, char **start, off_t off, 350 int count, int *eof, void *data) 351 { 352 int len = 0; 353 354 len += snprintf(page + len, PAGE_SIZE - len, "%s\n", 355 CAN_VERSION_STRING); 356 *eof = 1; 357 return len; 358 } 359 360 static int can_proc_read_rcvlist(char *page, char **start, off_t off, 361 int count, int *eof, void *data) 362 { 363 /* double cast to prevent GCC warning */ 364 int idx = (int)(long)data; 365 int len = 0; 366 struct dev_rcv_lists *d; 367 struct hlist_node *n; 368 369 len += snprintf(page + len, PAGE_SIZE - len, 370 "\nreceive list '%s':\n", rx_list_name[idx]); 371 372 rcu_read_lock(); 373 hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) { 374 375 if (!hlist_empty(&d->rx[idx])) { 376 len = can_print_recv_banner(page, len); 377 len = can_print_rcvlist(page, len, &d->rx[idx], d->dev); 378 } else 379 len += snprintf(page + len, PAGE_SIZE - len, 380 " (%s: no entry)\n", DNAME(d->dev)); 381 382 /* exit on end of buffer? */ 383 if (len > PAGE_SIZE - 100) 384 break; 385 } 386 rcu_read_unlock(); 387 388 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 389 390 *eof = 1; 391 return len; 392 } 393 394 static int can_proc_read_rcvlist_sff(char *page, char **start, off_t off, 395 int count, int *eof, void *data) 396 { 397 int len = 0; 398 struct dev_rcv_lists *d; 399 struct hlist_node *n; 400 401 /* RX_SFF */ 402 len += snprintf(page + len, PAGE_SIZE - len, 403 "\nreceive list 'rx_sff':\n"); 404 405 rcu_read_lock(); 406 hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) { 407 int i, all_empty = 1; 408 /* check wether at least one list is non-empty */ 409 for (i = 0; i < 0x800; i++) 410 if (!hlist_empty(&d->rx_sff[i])) { 411 all_empty = 0; 412 break; 413 } 414 415 if (!all_empty) { 416 len = can_print_recv_banner(page, len); 417 for (i = 0; i < 0x800; i++) { 418 if (!hlist_empty(&d->rx_sff[i]) && 419 len < PAGE_SIZE - 100) 420 len = can_print_rcvlist(page, len, 421 &d->rx_sff[i], 422 d->dev); 423 } 424 } else 425 len += snprintf(page + len, PAGE_SIZE - len, 426 " (%s: no entry)\n", DNAME(d->dev)); 427 428 /* exit on end of buffer? */ 429 if (len > PAGE_SIZE - 100) 430 break; 431 } 432 rcu_read_unlock(); 433 434 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 435 436 *eof = 1; 437 return len; 438 } 439 440 /* 441 * proc utility functions 442 */ 443 444 static struct proc_dir_entry *can_create_proc_readentry(const char *name, 445 mode_t mode, 446 read_proc_t *read_proc, 447 void *data) 448 { 449 if (can_dir) 450 return create_proc_read_entry(name, mode, can_dir, read_proc, 451 data); 452 else 453 return NULL; 454 } 455 456 static void can_remove_proc_readentry(const char *name) 457 { 458 if (can_dir) 459 remove_proc_entry(name, can_dir); 460 } 461 462 /* 463 * can_init_proc - create main CAN proc directory and procfs entries 464 */ 465 void can_init_proc(void) 466 { 467 /* create /proc/net/can directory */ 468 can_dir = proc_mkdir("can", init_net.proc_net); 469 470 if (!can_dir) { 471 printk(KERN_INFO "can: failed to create /proc/net/can . " 472 "CONFIG_PROC_FS missing?\n"); 473 return; 474 } 475 476 can_dir->owner = THIS_MODULE; 477 478 /* own procfs entries from the AF_CAN core */ 479 pde_version = can_create_proc_readentry(CAN_PROC_VERSION, 0644, 480 can_proc_read_version, NULL); 481 pde_stats = can_create_proc_readentry(CAN_PROC_STATS, 0644, 482 can_proc_read_stats, NULL); 483 pde_reset_stats = can_create_proc_readentry(CAN_PROC_RESET_STATS, 0644, 484 can_proc_read_reset_stats, NULL); 485 pde_rcvlist_err = can_create_proc_readentry(CAN_PROC_RCVLIST_ERR, 0644, 486 can_proc_read_rcvlist, (void *)RX_ERR); 487 pde_rcvlist_all = can_create_proc_readentry(CAN_PROC_RCVLIST_ALL, 0644, 488 can_proc_read_rcvlist, (void *)RX_ALL); 489 pde_rcvlist_fil = can_create_proc_readentry(CAN_PROC_RCVLIST_FIL, 0644, 490 can_proc_read_rcvlist, (void *)RX_FIL); 491 pde_rcvlist_inv = can_create_proc_readentry(CAN_PROC_RCVLIST_INV, 0644, 492 can_proc_read_rcvlist, (void *)RX_INV); 493 pde_rcvlist_eff = can_create_proc_readentry(CAN_PROC_RCVLIST_EFF, 0644, 494 can_proc_read_rcvlist, (void *)RX_EFF); 495 pde_rcvlist_sff = can_create_proc_readentry(CAN_PROC_RCVLIST_SFF, 0644, 496 can_proc_read_rcvlist_sff, NULL); 497 } 498 499 /* 500 * can_remove_proc - remove procfs entries and main CAN proc directory 501 */ 502 void can_remove_proc(void) 503 { 504 if (pde_version) 505 can_remove_proc_readentry(CAN_PROC_VERSION); 506 507 if (pde_stats) 508 can_remove_proc_readentry(CAN_PROC_STATS); 509 510 if (pde_reset_stats) 511 can_remove_proc_readentry(CAN_PROC_RESET_STATS); 512 513 if (pde_rcvlist_err) 514 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR); 515 516 if (pde_rcvlist_all) 517 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL); 518 519 if (pde_rcvlist_fil) 520 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL); 521 522 if (pde_rcvlist_inv) 523 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV); 524 525 if (pde_rcvlist_eff) 526 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF); 527 528 if (pde_rcvlist_sff) 529 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF); 530 531 if (can_dir) 532 proc_net_remove(&init_net, "can"); 533 } 534