blob: 1463653dbe34e986eb5f6283b7823ef109cb0fa8 [file] [log] [blame]
Oliver Hartkopp0d665482007-11-16 15:52:17 -08001/*
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
66static struct proc_dir_entry *can_dir;
67static struct proc_dir_entry *pde_version;
68static struct proc_dir_entry *pde_stats;
69static struct proc_dir_entry *pde_reset_stats;
70static struct proc_dir_entry *pde_rcvlist_all;
71static struct proc_dir_entry *pde_rcvlist_fil;
72static struct proc_dir_entry *pde_rcvlist_inv;
73static struct proc_dir_entry *pde_rcvlist_sff;
74static struct proc_dir_entry *pde_rcvlist_eff;
75static struct proc_dir_entry *pde_rcvlist_err;
76
77static int user_reset;
78
79static 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
91static 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
109static 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
129void 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
199static 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
231static 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
244static 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
324static 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
349static 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
360static 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
394static 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
444static 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
456static 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 */
465void 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
Oliver Hartkopp0d665482007-11-16 15:52:17 -0800476 /* own procfs entries from the AF_CAN core */
477 pde_version = can_create_proc_readentry(CAN_PROC_VERSION, 0644,
478 can_proc_read_version, NULL);
479 pde_stats = can_create_proc_readentry(CAN_PROC_STATS, 0644,
480 can_proc_read_stats, NULL);
481 pde_reset_stats = can_create_proc_readentry(CAN_PROC_RESET_STATS, 0644,
482 can_proc_read_reset_stats, NULL);
483 pde_rcvlist_err = can_create_proc_readentry(CAN_PROC_RCVLIST_ERR, 0644,
484 can_proc_read_rcvlist, (void *)RX_ERR);
485 pde_rcvlist_all = can_create_proc_readentry(CAN_PROC_RCVLIST_ALL, 0644,
486 can_proc_read_rcvlist, (void *)RX_ALL);
487 pde_rcvlist_fil = can_create_proc_readentry(CAN_PROC_RCVLIST_FIL, 0644,
488 can_proc_read_rcvlist, (void *)RX_FIL);
489 pde_rcvlist_inv = can_create_proc_readentry(CAN_PROC_RCVLIST_INV, 0644,
490 can_proc_read_rcvlist, (void *)RX_INV);
491 pde_rcvlist_eff = can_create_proc_readentry(CAN_PROC_RCVLIST_EFF, 0644,
492 can_proc_read_rcvlist, (void *)RX_EFF);
493 pde_rcvlist_sff = can_create_proc_readentry(CAN_PROC_RCVLIST_SFF, 0644,
494 can_proc_read_rcvlist_sff, NULL);
495}
496
497/*
498 * can_remove_proc - remove procfs entries and main CAN proc directory
499 */
500void can_remove_proc(void)
501{
502 if (pde_version)
503 can_remove_proc_readentry(CAN_PROC_VERSION);
504
505 if (pde_stats)
506 can_remove_proc_readentry(CAN_PROC_STATS);
507
508 if (pde_reset_stats)
509 can_remove_proc_readentry(CAN_PROC_RESET_STATS);
510
511 if (pde_rcvlist_err)
512 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
513
514 if (pde_rcvlist_all)
515 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
516
517 if (pde_rcvlist_fil)
518 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
519
520 if (pde_rcvlist_inv)
521 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
522
523 if (pde_rcvlist_eff)
524 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
525
526 if (pde_rcvlist_sff)
527 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
528
529 if (can_dir)
530 proc_net_remove(&init_net, "can");
531}