2 * proc.c - procfs support for Protocol family CAN core module
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions, the following disclaimer and
12 * the referenced file 'COPYING'.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of Volkswagen nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * Alternatively, provided that this notice is retained in full, this
21 * software may be distributed under the terms of the GNU General
22 * Public License ("GPL") version 2 as distributed in the 'COPYING'
23 * file from the main directory of the linux kernel source.
25 * The provided data structures and external interfaces from this code
26 * are not restricted to be used by modules with a GPL compatible license.
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
41 * Send feedback to <socketcan-users@lists.berlios.de>
45 #include <linux/module.h>
46 #include <linux/proc_fs.h>
47 #include <linux/list.h>
48 #include <linux/rcupdate.h>
49 #include <linux/can/core.h>
53 #include <linux/can/version.h> /* for RCSID. Removed by mkpatch script */
57 * proc filenames for the PF_CAN core
60 #define CAN_PROC_VERSION "version"
61 #define CAN_PROC_STATS "stats"
62 #define CAN_PROC_RESET_STATS "reset_stats"
63 #define CAN_PROC_RCVLIST_ALL "rcvlist_all"
64 #define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
65 #define CAN_PROC_RCVLIST_INV "rcvlist_inv"
66 #define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
67 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
68 #define CAN_PROC_RCVLIST_ERR "rcvlist_err"
70 static struct proc_dir_entry *can_dir;
71 static struct proc_dir_entry *pde_version;
72 static struct proc_dir_entry *pde_stats;
73 static struct proc_dir_entry *pde_reset_stats;
74 static struct proc_dir_entry *pde_rcvlist_all;
75 static struct proc_dir_entry *pde_rcvlist_fil;
76 static struct proc_dir_entry *pde_rcvlist_inv;
77 static struct proc_dir_entry *pde_rcvlist_sff;
78 static struct proc_dir_entry *pde_rcvlist_eff;
79 static struct proc_dir_entry *pde_rcvlist_err;
81 static int user_reset;
83 static const char *rx_list_name[] = {
92 * af_can statistics stuff
95 static void can_init_stats(void)
98 * This memset function is called from a timer context (when
99 * stattimer is active which is the default) OR in a process
100 * context (reading the proc_fs when stattimer is disabled).
102 memset(&stats, 0, sizeof(stats));
103 stats.jiffies_init = jiffies;
105 pstats.stats_reset++;
113 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
116 unsigned long ret = 0;
118 if (oldjif == newjif)
121 /* see can_stat_update() - this should NEVER happen! */
122 if (count > (ULONG_MAX / HZ)) {
123 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
128 ret = (count * HZ) / (newjif - oldjif);
133 void can_stat_update(unsigned long data)
135 unsigned long j = jiffies; /* snapshot */
137 /* restart counting in timer context on user request */
141 /* restart counting on jiffies overflow */
142 if (j < stats.jiffies_init)
145 /* prevent overflow in calc_rate() */
146 if (stats.rx_frames > (ULONG_MAX / HZ))
149 /* prevent overflow in calc_rate() */
150 if (stats.tx_frames > (ULONG_MAX / HZ))
153 /* matches overflow - very improbable */
154 if (stats.matches > (ULONG_MAX / 100))
157 /* calc total values */
159 stats.total_rx_match_ratio = (stats.matches * 100) /
162 stats.total_tx_rate = calc_rate(stats.jiffies_init, j,
164 stats.total_rx_rate = calc_rate(stats.jiffies_init, j,
167 /* calc current values */
168 if (stats.rx_frames_delta)
169 stats.current_rx_match_ratio =
170 (stats.matches_delta * 100) / stats.rx_frames_delta;
172 stats.current_tx_rate = calc_rate(0, HZ, stats.tx_frames_delta);
173 stats.current_rx_rate = calc_rate(0, HZ, stats.rx_frames_delta);
175 /* check / update maximum values */
176 if (stats.max_tx_rate < stats.current_tx_rate)
177 stats.max_tx_rate = stats.current_tx_rate;
179 if (stats.max_rx_rate < stats.current_rx_rate)
180 stats.max_rx_rate = stats.current_rx_rate;
182 if (stats.max_rx_match_ratio < stats.current_rx_match_ratio)
183 stats.max_rx_match_ratio = stats.current_rx_match_ratio;
185 /* clear values for 'current rate' calculation */
186 stats.tx_frames_delta = 0;
187 stats.rx_frames_delta = 0;
188 stats.matches_delta = 0;
190 /* restart timer (one second) */
191 stattimer.expires = round_jiffies(jiffies + HZ);
192 add_timer(&stattimer);
196 * proc read functions
198 * From known use-cases we expect about 10 entries in a receive list to be
199 * printed in the proc_fs. So PAGE_SIZE is definitely enough space here.
203 static int can_print_rcvlist(char *page, int len, struct hlist_head *rx_list,
204 struct net_device *dev)
207 struct hlist_node *n;
210 hlist_for_each_entry_rcu(r, n, rx_list, list) {
211 char *fmt = (r->can_id & CAN_EFF_FLAG)?
212 " %-5s %08X %08x %08x %08x %8ld %s\n" :
213 " %-5s %03X %08x %08lx %08lx %8ld %s\n";
215 len += snprintf(page + len, PAGE_SIZE - len, fmt,
216 DNAME(dev), r->can_id, r->mask,
217 (unsigned long)r->func, (unsigned long)r->data,
218 r->matches, r->ident);
220 /* does a typical line fit into the current buffer? */
222 /* 100 Bytes before end of buffer */
223 if (len > PAGE_SIZE - 100) {
224 /* mark output cut off */
225 len += snprintf(page + len, PAGE_SIZE - len,
235 static int can_print_recv_banner(char *page, int len)
238 * can1. 00000000 00000000 00000000
241 len += snprintf(page + len, PAGE_SIZE - len,
242 " device can_id can_mask function"
243 " userdata matches ident\n");
248 static int can_proc_read_stats(char *page, char **start, off_t off,
249 int count, int *eof, void *data)
253 len += snprintf(page + len, PAGE_SIZE - len, "\n");
254 len += snprintf(page + len, PAGE_SIZE - len,
255 " %8ld transmitted frames (TXF)\n", stats.tx_frames);
256 len += snprintf(page + len, PAGE_SIZE - len,
257 " %8ld received frames (RXF)\n", stats.rx_frames);
258 len += snprintf(page + len, PAGE_SIZE - len,
259 " %8ld matched frames (RXMF)\n", stats.matches);
261 len += snprintf(page + len, PAGE_SIZE - len, "\n");
263 if (stattimer.function == can_stat_update) {
264 len += snprintf(page + len, PAGE_SIZE - len,
265 " %8ld %% total match ratio (RXMR)\n",
266 stats.total_rx_match_ratio);
268 len += snprintf(page + len, PAGE_SIZE - len,
269 " %8ld frames/s total tx rate (TXR)\n",
270 stats.total_tx_rate);
271 len += snprintf(page + len, PAGE_SIZE - len,
272 " %8ld frames/s total rx rate (RXR)\n",
273 stats.total_rx_rate);
275 len += snprintf(page + len, PAGE_SIZE - len, "\n");
277 len += snprintf(page + len, PAGE_SIZE - len,
278 " %8ld %% current match ratio (CRXMR)\n",
279 stats.current_rx_match_ratio);
281 len += snprintf(page + len, PAGE_SIZE - len,
282 " %8ld frames/s current tx rate (CTXR)\n",
283 stats.current_tx_rate);
284 len += snprintf(page + len, PAGE_SIZE - len,
285 " %8ld frames/s current rx rate (CRXR)\n",
286 stats.current_rx_rate);
288 len += snprintf(page + len, PAGE_SIZE - len, "\n");
290 len += snprintf(page + len, PAGE_SIZE - len,
291 " %8ld %% max match ratio (MRXMR)\n",
292 stats.max_rx_match_ratio);
294 len += snprintf(page + len, PAGE_SIZE - len,
295 " %8ld frames/s max tx rate (MTXR)\n",
297 len += snprintf(page + len, PAGE_SIZE - len,
298 " %8ld frames/s max rx rate (MRXR)\n",
301 len += snprintf(page + len, PAGE_SIZE - len, "\n");
304 len += snprintf(page + len, PAGE_SIZE - len,
305 " %8ld current receive list entries (CRCV)\n",
307 len += snprintf(page + len, PAGE_SIZE - len,
308 " %8ld maximum receive list entries (MRCV)\n",
309 pstats.rcv_entries_max);
311 if (pstats.stats_reset)
312 len += snprintf(page + len, PAGE_SIZE - len,
313 "\n %8ld statistic resets (STR)\n",
316 if (pstats.user_reset)
317 len += snprintf(page + len, PAGE_SIZE - len,
318 " %8ld user statistic resets (USTR)\n",
321 len += snprintf(page + len, PAGE_SIZE - len, "\n");
327 static int can_proc_read_reset_stats(char *page, char **start, off_t off,
328 int count, int *eof, void *data)
334 if (stattimer.function == can_stat_update) {
335 len += snprintf(page + len, PAGE_SIZE - len,
336 "Scheduled statistic reset #%ld.\n",
337 pstats.stats_reset + 1);
340 if (stats.jiffies_init != jiffies)
343 len += snprintf(page + len, PAGE_SIZE - len,
344 "Performed statistic reset #%ld.\n",
352 static int can_proc_read_version(char *page, char **start, off_t off,
353 int count, int *eof, void *data)
357 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
363 static int can_proc_read_rcvlist(char *page, char **start, off_t off,
364 int count, int *eof, void *data)
366 /* double cast to prevent GCC warning */
367 int idx = (int)(long)data;
369 struct dev_rcv_lists *d;
370 struct hlist_node *n;
372 len += snprintf(page + len, PAGE_SIZE - len,
373 "\nreceive list '%s':\n", rx_list_name[idx]);
376 hlist_for_each_entry_rcu(d, n, &rx_dev_list, list) {
378 if (!hlist_empty(&d->rx[idx])) {
379 len = can_print_recv_banner(page, len);
380 len = can_print_rcvlist(page, len, &d->rx[idx], d->dev);
382 len += snprintf(page + len, PAGE_SIZE - len,
383 " (%s: no entry)\n", DNAME(d->dev));
385 /* exit on end of buffer? */
386 if (len > PAGE_SIZE - 100)
391 len += snprintf(page + len, PAGE_SIZE - len, "\n");
397 static int can_proc_read_rcvlist_sff(char *page, char **start, off_t off,
398 int count, int *eof, void *data)
401 struct dev_rcv_lists *d;
402 struct hlist_node *n;
405 len += snprintf(page + len, PAGE_SIZE - len,
406 "\nreceive list 'rx_sff':\n");
409 hlist_for_each_entry_rcu(d, n, &rx_dev_list, list) {
410 int i, all_empty = 1;
411 /* check wether at least one list is non-empty */
412 for (i = 0; i < 0x800; i++)
413 if (!hlist_empty(&d->rx_sff[i])) {
419 len = can_print_recv_banner(page, len);
420 for (i = 0; i < 0x800; i++) {
421 if (!hlist_empty(&d->rx_sff[i]) &&
422 len < PAGE_SIZE - 100)
423 len = can_print_rcvlist(page, len,
428 len += snprintf(page + len, PAGE_SIZE - len,
429 " (%s: no entry)\n", DNAME(d->dev));
431 /* exit on end of buffer? */
432 if (len > PAGE_SIZE - 100)
437 len += snprintf(page + len, PAGE_SIZE - len, "\n");
444 * proc utility functions
447 static struct proc_dir_entry *can_create_proc_readentry(const char *name,
449 read_proc_t *read_proc,
453 return create_proc_read_entry(name, mode, can_dir, read_proc,
459 static void can_remove_proc_readentry(const char *name)
462 remove_proc_entry(name, can_dir);
466 * can_init_proc - create main CAN proc directory and procfs entries
468 void can_init_proc(void)
470 /* create /proc/net/can directory */
471 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
472 can_dir = proc_mkdir("can", init_net.proc_net);
474 can_dir = proc_mkdir("can", proc_net);
478 printk(KERN_INFO "can: failed to create /proc/net/can . "
479 "CONFIG_PROC_FS missing?\n");
483 can_dir->owner = THIS_MODULE;
485 /* own procfs entries from the AF_CAN core */
486 pde_version = can_create_proc_readentry(CAN_PROC_VERSION, 0644,
487 can_proc_read_version, NULL);
488 pde_stats = can_create_proc_readentry(CAN_PROC_STATS, 0644,
489 can_proc_read_stats, NULL);
490 pde_reset_stats = can_create_proc_readentry(CAN_PROC_RESET_STATS, 0644,
491 can_proc_read_reset_stats, NULL);
492 pde_rcvlist_err = can_create_proc_readentry(CAN_PROC_RCVLIST_ERR, 0644,
493 can_proc_read_rcvlist, (void *)RX_ERR);
494 pde_rcvlist_all = can_create_proc_readentry(CAN_PROC_RCVLIST_ALL, 0644,
495 can_proc_read_rcvlist, (void *)RX_ALL);
496 pde_rcvlist_fil = can_create_proc_readentry(CAN_PROC_RCVLIST_FIL, 0644,
497 can_proc_read_rcvlist, (void *)RX_FIL);
498 pde_rcvlist_inv = can_create_proc_readentry(CAN_PROC_RCVLIST_INV, 0644,
499 can_proc_read_rcvlist, (void *)RX_INV);
500 pde_rcvlist_eff = can_create_proc_readentry(CAN_PROC_RCVLIST_EFF, 0644,
501 can_proc_read_rcvlist, (void *)RX_EFF);
502 pde_rcvlist_sff = can_create_proc_readentry(CAN_PROC_RCVLIST_SFF, 0644,
503 can_proc_read_rcvlist_sff, NULL);
507 * can_remove_proc - remove procfs entries and main CAN proc directory
509 void can_remove_proc(void)
512 can_remove_proc_readentry(CAN_PROC_VERSION);
515 can_remove_proc_readentry(CAN_PROC_STATS);
518 can_remove_proc_readentry(CAN_PROC_RESET_STATS);
521 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
524 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
527 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
530 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
533 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
536 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
539 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
540 proc_net_remove(&init_net, "can");
542 proc_net_remove("can");