2 * proc.c - procfs support for Protocol family CAN core module
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
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16 * may be used to endorse or promote products derived from this software
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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.
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.
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44 #include <linux/module.h>
45 #include <linux/version.h>
46 #include <linux/proc_fs.h>
47 #include <linux/list.h>
48 #include <linux/rcupdate.h>
49 #include <linux/can/core.h>
52 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
56 #include <linux/can/version.h> /* for RCSID. Removed by mkpatch script */
60 * proc filenames for the PF_CAN core
63 #define CAN_PROC_VERSION "version"
64 #define CAN_PROC_STATS "stats"
65 #define CAN_PROC_RESET_STATS "reset_stats"
66 #define CAN_PROC_RCVLIST_ALL "rcvlist_all"
67 #define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
68 #define CAN_PROC_RCVLIST_INV "rcvlist_inv"
69 #define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
70 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
71 #define CAN_PROC_RCVLIST_ERR "rcvlist_err"
73 static struct proc_dir_entry *can_dir;
74 static struct proc_dir_entry *pde_version;
75 static struct proc_dir_entry *pde_stats;
76 static struct proc_dir_entry *pde_reset_stats;
77 static struct proc_dir_entry *pde_rcvlist_all;
78 static struct proc_dir_entry *pde_rcvlist_fil;
79 static struct proc_dir_entry *pde_rcvlist_inv;
80 static struct proc_dir_entry *pde_rcvlist_sff;
81 static struct proc_dir_entry *pde_rcvlist_eff;
82 static struct proc_dir_entry *pde_rcvlist_err;
84 static int user_reset;
86 static const char rx_list_name[][8] = {
95 * af_can statistics stuff
98 static void can_init_stats(void)
101 * This memset function is called from a timer context (when
102 * can_stattimer is active which is the default) OR in a process
103 * context (reading the proc_fs when can_stattimer is disabled).
105 memset(&can_stats, 0, sizeof(can_stats));
106 can_stats.jiffies_init = jiffies;
108 can_pstats.stats_reset++;
112 can_pstats.user_reset++;
116 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
121 if (oldjif == newjif)
124 /* see can_stat_update() - this should NEVER happen! */
125 if (count > (ULONG_MAX / HZ)) {
126 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
131 rate = (count * HZ) / (newjif - oldjif);
136 void can_stat_update(unsigned long data)
138 unsigned long j = jiffies; /* snapshot */
140 /* restart counting in timer context on user request */
144 /* restart counting on jiffies overflow */
145 if (j < can_stats.jiffies_init)
148 /* prevent overflow in calc_rate() */
149 if (can_stats.rx_frames > (ULONG_MAX / HZ))
152 /* prevent overflow in calc_rate() */
153 if (can_stats.tx_frames > (ULONG_MAX / HZ))
156 /* matches overflow - very improbable */
157 if (can_stats.matches > (ULONG_MAX / 100))
160 /* calc total values */
161 if (can_stats.rx_frames)
162 can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
165 can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
166 can_stats.tx_frames);
167 can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
168 can_stats.rx_frames);
170 /* calc current values */
171 if (can_stats.rx_frames_delta)
172 can_stats.current_rx_match_ratio =
173 (can_stats.matches_delta * 100) /
174 can_stats.rx_frames_delta;
176 can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
177 can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);
179 /* check / update maximum values */
180 if (can_stats.max_tx_rate < can_stats.current_tx_rate)
181 can_stats.max_tx_rate = can_stats.current_tx_rate;
183 if (can_stats.max_rx_rate < can_stats.current_rx_rate)
184 can_stats.max_rx_rate = can_stats.current_rx_rate;
186 if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
187 can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;
189 /* clear values for 'current rate' calculation */
190 can_stats.tx_frames_delta = 0;
191 can_stats.rx_frames_delta = 0;
192 can_stats.matches_delta = 0;
194 /* restart timer (one second) */
195 mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
199 * proc read functions
201 * From known use-cases we expect about 10 entries in a receive list to be
202 * printed in the proc_fs. So PAGE_SIZE is definitely enough space here.
206 static int can_print_rcvlist(char *page, int len, struct hlist_head *rx_list,
207 struct net_device *dev)
210 struct hlist_node *n;
213 hlist_for_each_entry_rcu(r, n, rx_list, list) {
214 char *fmt = (r->can_id & CAN_EFF_FLAG)?
215 " %-5s %08X %08x %08x %08x %8ld %s\n" :
216 " %-5s %03X %08x %08lx %08lx %8ld %s\n";
218 len += snprintf(page + len, PAGE_SIZE - len, fmt,
219 DNAME(dev), r->can_id, r->mask,
220 (unsigned long)r->func, (unsigned long)r->data,
221 r->matches, r->ident);
223 /* does a typical line fit into the current buffer? */
225 /* 100 Bytes before end of buffer */
226 if (len > PAGE_SIZE - 100) {
227 /* mark output cut off */
228 len += snprintf(page + len, PAGE_SIZE - len,
238 static int can_print_recv_banner(char *page, int len)
241 * can1. 00000000 00000000 00000000
244 len += snprintf(page + len, PAGE_SIZE - len,
245 " device can_id can_mask function"
246 " userdata matches ident\n");
251 static int can_proc_read_stats(char *page, char **start, off_t off,
252 int count, int *eof, void *data)
256 len += snprintf(page + len, PAGE_SIZE - len, "\n");
257 len += snprintf(page + len, PAGE_SIZE - len,
258 " %8ld transmitted frames (TXF)\n",
259 can_stats.tx_frames);
260 len += snprintf(page + len, PAGE_SIZE - len,
261 " %8ld received frames (RXF)\n", can_stats.rx_frames);
262 len += snprintf(page + len, PAGE_SIZE - len,
263 " %8ld matched frames (RXMF)\n", can_stats.matches);
265 len += snprintf(page + len, PAGE_SIZE - len, "\n");
267 if (can_stattimer.function == can_stat_update) {
268 len += snprintf(page + len, PAGE_SIZE - len,
269 " %8ld %% total match ratio (RXMR)\n",
270 can_stats.total_rx_match_ratio);
272 len += snprintf(page + len, PAGE_SIZE - len,
273 " %8ld frames/s total tx rate (TXR)\n",
274 can_stats.total_tx_rate);
275 len += snprintf(page + len, PAGE_SIZE - len,
276 " %8ld frames/s total rx rate (RXR)\n",
277 can_stats.total_rx_rate);
279 len += snprintf(page + len, PAGE_SIZE - len, "\n");
281 len += snprintf(page + len, PAGE_SIZE - len,
282 " %8ld %% current match ratio (CRXMR)\n",
283 can_stats.current_rx_match_ratio);
285 len += snprintf(page + len, PAGE_SIZE - len,
286 " %8ld frames/s current tx rate (CTXR)\n",
287 can_stats.current_tx_rate);
288 len += snprintf(page + len, PAGE_SIZE - len,
289 " %8ld frames/s current rx rate (CRXR)\n",
290 can_stats.current_rx_rate);
292 len += snprintf(page + len, PAGE_SIZE - len, "\n");
294 len += snprintf(page + len, PAGE_SIZE - len,
295 " %8ld %% max match ratio (MRXMR)\n",
296 can_stats.max_rx_match_ratio);
298 len += snprintf(page + len, PAGE_SIZE - len,
299 " %8ld frames/s max tx rate (MTXR)\n",
300 can_stats.max_tx_rate);
301 len += snprintf(page + len, PAGE_SIZE - len,
302 " %8ld frames/s max rx rate (MRXR)\n",
303 can_stats.max_rx_rate);
305 len += snprintf(page + len, PAGE_SIZE - len, "\n");
308 len += snprintf(page + len, PAGE_SIZE - len,
309 " %8ld current receive list entries (CRCV)\n",
310 can_pstats.rcv_entries);
311 len += snprintf(page + len, PAGE_SIZE - len,
312 " %8ld maximum receive list entries (MRCV)\n",
313 can_pstats.rcv_entries_max);
315 if (can_pstats.stats_reset)
316 len += snprintf(page + len, PAGE_SIZE - len,
317 "\n %8ld statistic resets (STR)\n",
318 can_pstats.stats_reset);
320 if (can_pstats.user_reset)
321 len += snprintf(page + len, PAGE_SIZE - len,
322 " %8ld user statistic resets (USTR)\n",
323 can_pstats.user_reset);
325 len += snprintf(page + len, PAGE_SIZE - len, "\n");
331 static int can_proc_read_reset_stats(char *page, char **start, off_t off,
332 int count, int *eof, void *data)
338 if (can_stattimer.function == can_stat_update) {
339 len += snprintf(page + len, PAGE_SIZE - len,
340 "Scheduled statistic reset #%ld.\n",
341 can_pstats.stats_reset + 1);
344 if (can_stats.jiffies_init != jiffies)
347 len += snprintf(page + len, PAGE_SIZE - len,
348 "Performed statistic reset #%ld.\n",
349 can_pstats.stats_reset);
356 static int can_proc_read_version(char *page, char **start, off_t off,
357 int count, int *eof, void *data)
361 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
367 static int can_proc_read_rcvlist(char *page, char **start, off_t off,
368 int count, int *eof, void *data)
370 /* double cast to prevent GCC warning */
371 int idx = (int)(long)data;
373 struct dev_rcv_lists *d;
374 struct hlist_node *n;
376 len += snprintf(page + len, PAGE_SIZE - len,
377 "\nreceive list '%s':\n", rx_list_name[idx]);
380 hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) {
382 if (!hlist_empty(&d->rx[idx])) {
383 len = can_print_recv_banner(page, len);
384 len = can_print_rcvlist(page, len, &d->rx[idx], d->dev);
386 len += snprintf(page + len, PAGE_SIZE - len,
387 " (%s: no entry)\n", DNAME(d->dev));
389 /* exit on end of buffer? */
390 if (len > PAGE_SIZE - 100)
395 len += snprintf(page + len, PAGE_SIZE - len, "\n");
401 static int can_proc_read_rcvlist_sff(char *page, char **start, off_t off,
402 int count, int *eof, void *data)
405 struct dev_rcv_lists *d;
406 struct hlist_node *n;
409 len += snprintf(page + len, PAGE_SIZE - len,
410 "\nreceive list 'rx_sff':\n");
413 hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) {
414 int i, all_empty = 1;
415 /* check wether at least one list is non-empty */
416 for (i = 0; i < 0x800; i++)
417 if (!hlist_empty(&d->rx_sff[i])) {
423 len = can_print_recv_banner(page, len);
424 for (i = 0; i < 0x800; i++) {
425 if (!hlist_empty(&d->rx_sff[i]) &&
426 len < PAGE_SIZE - 100)
427 len = can_print_rcvlist(page, len,
432 len += snprintf(page + len, PAGE_SIZE - len,
433 " (%s: no entry)\n", DNAME(d->dev));
435 /* exit on end of buffer? */
436 if (len > PAGE_SIZE - 100)
441 len += snprintf(page + len, PAGE_SIZE - len, "\n");
448 * proc utility functions
451 static struct proc_dir_entry *can_create_proc_readentry(const char *name,
453 read_proc_t *read_proc,
457 return create_proc_read_entry(name, mode, can_dir, read_proc,
463 static void can_remove_proc_readentry(const char *name)
466 remove_proc_entry(name, can_dir);
470 * can_init_proc - create main CAN proc directory and procfs entries
472 void can_init_proc(void)
474 /* create /proc/net/can directory */
475 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
476 can_dir = proc_mkdir("can", init_net.proc_net);
478 can_dir = proc_mkdir("can", proc_net);
482 printk(KERN_INFO "can: failed to create /proc/net/can . "
483 "CONFIG_PROC_FS missing?\n");
487 can_dir->owner = THIS_MODULE;
489 /* own procfs entries from the AF_CAN core */
490 pde_version = can_create_proc_readentry(CAN_PROC_VERSION, 0644,
491 can_proc_read_version, NULL);
492 pde_stats = can_create_proc_readentry(CAN_PROC_STATS, 0644,
493 can_proc_read_stats, NULL);
494 pde_reset_stats = can_create_proc_readentry(CAN_PROC_RESET_STATS, 0644,
495 can_proc_read_reset_stats, NULL);
496 pde_rcvlist_err = can_create_proc_readentry(CAN_PROC_RCVLIST_ERR, 0644,
497 can_proc_read_rcvlist, (void *)RX_ERR);
498 pde_rcvlist_all = can_create_proc_readentry(CAN_PROC_RCVLIST_ALL, 0644,
499 can_proc_read_rcvlist, (void *)RX_ALL);
500 pde_rcvlist_fil = can_create_proc_readentry(CAN_PROC_RCVLIST_FIL, 0644,
501 can_proc_read_rcvlist, (void *)RX_FIL);
502 pde_rcvlist_inv = can_create_proc_readentry(CAN_PROC_RCVLIST_INV, 0644,
503 can_proc_read_rcvlist, (void *)RX_INV);
504 pde_rcvlist_eff = can_create_proc_readentry(CAN_PROC_RCVLIST_EFF, 0644,
505 can_proc_read_rcvlist, (void *)RX_EFF);
506 pde_rcvlist_sff = can_create_proc_readentry(CAN_PROC_RCVLIST_SFF, 0644,
507 can_proc_read_rcvlist_sff, NULL);
511 * can_remove_proc - remove procfs entries and main CAN proc directory
513 void can_remove_proc(void)
516 can_remove_proc_readentry(CAN_PROC_VERSION);
519 can_remove_proc_readentry(CAN_PROC_STATS);
522 can_remove_proc_readentry(CAN_PROC_RESET_STATS);
525 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
528 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
531 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
534 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
537 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
540 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
543 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
544 proc_net_remove(&init_net, "can");
546 proc_net_remove("can");