2 * proc.c - procfs support for Protocol family CAN core module
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
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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
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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>
52 #include <linux/can/version.h> /* for RCSID. Removed by mkpatch script */
56 * proc filenames for the PF_CAN core
59 #define CAN_PROC_VERSION "version"
60 #define CAN_PROC_STATS "stats"
61 #define CAN_PROC_RESET_STATS "reset_stats"
62 #define CAN_PROC_RCVLIST_ALL "rcvlist_all"
63 #define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
64 #define CAN_PROC_RCVLIST_INV "rcvlist_inv"
65 #define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
66 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
67 #define CAN_PROC_RCVLIST_ERR "rcvlist_err"
69 static struct proc_dir_entry *can_dir;
70 static struct proc_dir_entry *pde_version;
71 static struct proc_dir_entry *pde_stats;
72 static struct proc_dir_entry *pde_reset_stats;
73 static struct proc_dir_entry *pde_rcvlist_all;
74 static struct proc_dir_entry *pde_rcvlist_fil;
75 static struct proc_dir_entry *pde_rcvlist_inv;
76 static struct proc_dir_entry *pde_rcvlist_sff;
77 static struct proc_dir_entry *pde_rcvlist_eff;
78 static struct proc_dir_entry *pde_rcvlist_err;
80 static int user_reset;
82 static const char rx_list_name[][8] = {
91 * af_can statistics stuff
94 static void can_init_stats(void)
97 * This memset function is called from a timer context (when
98 * stattimer is active which is the default) OR in a process
99 * context (reading the proc_fs when stattimer is disabled).
101 memset(&stats, 0, sizeof(stats));
102 stats.jiffies_init = jiffies;
104 pstats.stats_reset++;
112 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
115 unsigned long ret = 0;
117 if (oldjif == newjif)
120 /* see can_stat_update() - this should NEVER happen! */
121 if (count > (ULONG_MAX / HZ)) {
122 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
127 ret = (count * HZ) / (newjif - oldjif);
132 void can_stat_update(unsigned long data)
134 unsigned long j = jiffies; /* snapshot */
136 /* restart counting in timer context on user request */
140 /* restart counting on jiffies overflow */
141 if (j < stats.jiffies_init)
144 /* prevent overflow in calc_rate() */
145 if (stats.rx_frames > (ULONG_MAX / HZ))
148 /* prevent overflow in calc_rate() */
149 if (stats.tx_frames > (ULONG_MAX / HZ))
152 /* matches overflow - very improbable */
153 if (stats.matches > (ULONG_MAX / 100))
156 /* calc total values */
158 stats.total_rx_match_ratio = (stats.matches * 100) /
161 stats.total_tx_rate = calc_rate(stats.jiffies_init, j,
163 stats.total_rx_rate = calc_rate(stats.jiffies_init, j,
166 /* calc current values */
167 if (stats.rx_frames_delta)
168 stats.current_rx_match_ratio =
169 (stats.matches_delta * 100) / stats.rx_frames_delta;
171 stats.current_tx_rate = calc_rate(0, HZ, stats.tx_frames_delta);
172 stats.current_rx_rate = calc_rate(0, HZ, stats.rx_frames_delta);
174 /* check / update maximum values */
175 if (stats.max_tx_rate < stats.current_tx_rate)
176 stats.max_tx_rate = stats.current_tx_rate;
178 if (stats.max_rx_rate < stats.current_rx_rate)
179 stats.max_rx_rate = stats.current_rx_rate;
181 if (stats.max_rx_match_ratio < stats.current_rx_match_ratio)
182 stats.max_rx_match_ratio = stats.current_rx_match_ratio;
184 /* clear values for 'current rate' calculation */
185 stats.tx_frames_delta = 0;
186 stats.rx_frames_delta = 0;
187 stats.matches_delta = 0;
189 /* restart timer (one second) */
190 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20)
191 stattimer.expires = round_jiffies(jiffies + HZ);
193 stattimer.expires = jiffies + HZ;
195 add_timer(&stattimer);
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", stats.tx_frames);
259 len += snprintf(page + len, PAGE_SIZE - len,
260 " %8ld received frames (RXF)\n", stats.rx_frames);
261 len += snprintf(page + len, PAGE_SIZE - len,
262 " %8ld matched frames (RXMF)\n", stats.matches);
264 len += snprintf(page + len, PAGE_SIZE - len, "\n");
266 if (stattimer.function == can_stat_update) {
267 len += snprintf(page + len, PAGE_SIZE - len,
268 " %8ld %% total match ratio (RXMR)\n",
269 stats.total_rx_match_ratio);
271 len += snprintf(page + len, PAGE_SIZE - len,
272 " %8ld frames/s total tx rate (TXR)\n",
273 stats.total_tx_rate);
274 len += snprintf(page + len, PAGE_SIZE - len,
275 " %8ld frames/s total rx rate (RXR)\n",
276 stats.total_rx_rate);
278 len += snprintf(page + len, PAGE_SIZE - len, "\n");
280 len += snprintf(page + len, PAGE_SIZE - len,
281 " %8ld %% current match ratio (CRXMR)\n",
282 stats.current_rx_match_ratio);
284 len += snprintf(page + len, PAGE_SIZE - len,
285 " %8ld frames/s current tx rate (CTXR)\n",
286 stats.current_tx_rate);
287 len += snprintf(page + len, PAGE_SIZE - len,
288 " %8ld frames/s current rx rate (CRXR)\n",
289 stats.current_rx_rate);
291 len += snprintf(page + len, PAGE_SIZE - len, "\n");
293 len += snprintf(page + len, PAGE_SIZE - len,
294 " %8ld %% max match ratio (MRXMR)\n",
295 stats.max_rx_match_ratio);
297 len += snprintf(page + len, PAGE_SIZE - len,
298 " %8ld frames/s max tx rate (MTXR)\n",
300 len += snprintf(page + len, PAGE_SIZE - len,
301 " %8ld frames/s max rx rate (MRXR)\n",
304 len += snprintf(page + len, PAGE_SIZE - len, "\n");
307 len += snprintf(page + len, PAGE_SIZE - len,
308 " %8ld current receive list entries (CRCV)\n",
310 len += snprintf(page + len, PAGE_SIZE - len,
311 " %8ld maximum receive list entries (MRCV)\n",
312 pstats.rcv_entries_max);
314 if (pstats.stats_reset)
315 len += snprintf(page + len, PAGE_SIZE - len,
316 "\n %8ld statistic resets (STR)\n",
319 if (pstats.user_reset)
320 len += snprintf(page + len, PAGE_SIZE - len,
321 " %8ld user statistic resets (USTR)\n",
324 len += snprintf(page + len, PAGE_SIZE - len, "\n");
330 static int can_proc_read_reset_stats(char *page, char **start, off_t off,
331 int count, int *eof, void *data)
337 if (stattimer.function == can_stat_update) {
338 len += snprintf(page + len, PAGE_SIZE - len,
339 "Scheduled statistic reset #%ld.\n",
340 pstats.stats_reset + 1);
343 if (stats.jiffies_init != jiffies)
346 len += snprintf(page + len, PAGE_SIZE - len,
347 "Performed statistic reset #%ld.\n",
355 static int can_proc_read_version(char *page, char **start, off_t off,
356 int count, int *eof, void *data)
360 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
366 static int can_proc_read_rcvlist(char *page, char **start, off_t off,
367 int count, int *eof, void *data)
369 /* double cast to prevent GCC warning */
370 int idx = (int)(long)data;
372 struct dev_rcv_lists *d;
373 struct hlist_node *n;
375 len += snprintf(page + len, PAGE_SIZE - len,
376 "\nreceive list '%s':\n", rx_list_name[idx]);
379 hlist_for_each_entry_rcu(d, n, &rx_dev_list, list) {
381 if (!hlist_empty(&d->rx[idx])) {
382 len = can_print_recv_banner(page, len);
383 len = can_print_rcvlist(page, len, &d->rx[idx], d->dev);
385 len += snprintf(page + len, PAGE_SIZE - len,
386 " (%s: no entry)\n", DNAME(d->dev));
388 /* exit on end of buffer? */
389 if (len > PAGE_SIZE - 100)
394 len += snprintf(page + len, PAGE_SIZE - len, "\n");
400 static int can_proc_read_rcvlist_sff(char *page, char **start, off_t off,
401 int count, int *eof, void *data)
404 struct dev_rcv_lists *d;
405 struct hlist_node *n;
408 len += snprintf(page + len, PAGE_SIZE - len,
409 "\nreceive list 'rx_sff':\n");
412 hlist_for_each_entry_rcu(d, n, &rx_dev_list, list) {
413 int i, all_empty = 1;
414 /* check wether at least one list is non-empty */
415 for (i = 0; i < 0x800; i++)
416 if (!hlist_empty(&d->rx_sff[i])) {
422 len = can_print_recv_banner(page, len);
423 for (i = 0; i < 0x800; i++) {
424 if (!hlist_empty(&d->rx_sff[i]) &&
425 len < PAGE_SIZE - 100)
426 len = can_print_rcvlist(page, len,
431 len += snprintf(page + len, PAGE_SIZE - len,
432 " (%s: no entry)\n", DNAME(d->dev));
434 /* exit on end of buffer? */
435 if (len > PAGE_SIZE - 100)
440 len += snprintf(page + len, PAGE_SIZE - len, "\n");
447 * proc utility functions
450 static struct proc_dir_entry *can_create_proc_readentry(const char *name,
452 read_proc_t *read_proc,
456 return create_proc_read_entry(name, mode, can_dir, read_proc,
462 static void can_remove_proc_readentry(const char *name)
465 remove_proc_entry(name, can_dir);
469 * can_init_proc - create main CAN proc directory and procfs entries
471 void can_init_proc(void)
473 /* create /proc/net/can directory */
474 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
475 can_dir = proc_mkdir("can", init_net.proc_net);
477 can_dir = proc_mkdir("can", proc_net);
481 printk(KERN_INFO "can: failed to create /proc/net/can . "
482 "CONFIG_PROC_FS missing?\n");
486 can_dir->owner = THIS_MODULE;
488 /* own procfs entries from the AF_CAN core */
489 pde_version = can_create_proc_readentry(CAN_PROC_VERSION, 0644,
490 can_proc_read_version, NULL);
491 pde_stats = can_create_proc_readentry(CAN_PROC_STATS, 0644,
492 can_proc_read_stats, NULL);
493 pde_reset_stats = can_create_proc_readentry(CAN_PROC_RESET_STATS, 0644,
494 can_proc_read_reset_stats, NULL);
495 pde_rcvlist_err = can_create_proc_readentry(CAN_PROC_RCVLIST_ERR, 0644,
496 can_proc_read_rcvlist, (void *)RX_ERR);
497 pde_rcvlist_all = can_create_proc_readentry(CAN_PROC_RCVLIST_ALL, 0644,
498 can_proc_read_rcvlist, (void *)RX_ALL);
499 pde_rcvlist_fil = can_create_proc_readentry(CAN_PROC_RCVLIST_FIL, 0644,
500 can_proc_read_rcvlist, (void *)RX_FIL);
501 pde_rcvlist_inv = can_create_proc_readentry(CAN_PROC_RCVLIST_INV, 0644,
502 can_proc_read_rcvlist, (void *)RX_INV);
503 pde_rcvlist_eff = can_create_proc_readentry(CAN_PROC_RCVLIST_EFF, 0644,
504 can_proc_read_rcvlist, (void *)RX_EFF);
505 pde_rcvlist_sff = can_create_proc_readentry(CAN_PROC_RCVLIST_SFF, 0644,
506 can_proc_read_rcvlist_sff, NULL);
510 * can_remove_proc - remove procfs entries and main CAN proc directory
512 void can_remove_proc(void)
515 can_remove_proc_readentry(CAN_PROC_VERSION);
518 can_remove_proc_readentry(CAN_PROC_STATS);
521 can_remove_proc_readentry(CAN_PROC_RESET_STATS);
524 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
527 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
530 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
533 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
536 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
539 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
542 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
543 proc_net_remove(&init_net, "can");
545 proc_net_remove("can");