xref: /linux/net/can/proc.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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/if_arp.h>
49 #include <linux/can/core.h>
50 
51 #include "af_can.h"
52 
53 /*
54  * proc filenames for the PF_CAN core
55  */
56 
57 #define CAN_PROC_VERSION     "version"
58 #define CAN_PROC_STATS       "stats"
59 #define CAN_PROC_RESET_STATS "reset_stats"
60 #define CAN_PROC_RCVLIST_ALL "rcvlist_all"
61 #define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
62 #define CAN_PROC_RCVLIST_INV "rcvlist_inv"
63 #define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
64 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
65 #define CAN_PROC_RCVLIST_ERR "rcvlist_err"
66 
67 static struct proc_dir_entry *can_dir;
68 static struct proc_dir_entry *pde_version;
69 static struct proc_dir_entry *pde_stats;
70 static struct proc_dir_entry *pde_reset_stats;
71 static struct proc_dir_entry *pde_rcvlist_all;
72 static struct proc_dir_entry *pde_rcvlist_fil;
73 static struct proc_dir_entry *pde_rcvlist_inv;
74 static struct proc_dir_entry *pde_rcvlist_sff;
75 static struct proc_dir_entry *pde_rcvlist_eff;
76 static struct proc_dir_entry *pde_rcvlist_err;
77 
78 static int user_reset;
79 
80 static const char rx_list_name[][8] = {
81 	[RX_ERR] = "rx_err",
82 	[RX_ALL] = "rx_all",
83 	[RX_FIL] = "rx_fil",
84 	[RX_INV] = "rx_inv",
85 	[RX_EFF] = "rx_eff",
86 };
87 
88 /* receive filters subscribed for 'all' CAN devices */
89 extern struct dev_rcv_lists can_rx_alldev_list;
90 
91 /*
92  * af_can statistics stuff
93  */
94 
95 static void can_init_stats(void)
96 {
97 	/*
98 	 * This memset function is called from a timer context (when
99 	 * can_stattimer is active which is the default) OR in a process
100 	 * context (reading the proc_fs when can_stattimer is disabled).
101 	 */
102 	memset(&can_stats, 0, sizeof(can_stats));
103 	can_stats.jiffies_init = jiffies;
104 
105 	can_pstats.stats_reset++;
106 
107 	if (user_reset) {
108 		user_reset = 0;
109 		can_pstats.user_reset++;
110 	}
111 }
112 
113 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
114 			       unsigned long count)
115 {
116 	unsigned long rate;
117 
118 	if (oldjif == newjif)
119 		return 0;
120 
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",
124 		       count);
125 		return 99999999;
126 	}
127 
128 	rate = (count * HZ) / (newjif - oldjif);
129 
130 	return rate;
131 }
132 
133 void can_stat_update(unsigned long data)
134 {
135 	unsigned long j = jiffies; /* snapshot */
136 
137 	/* restart counting in timer context on user request */
138 	if (user_reset)
139 		can_init_stats();
140 
141 	/* restart counting on jiffies overflow */
142 	if (j < can_stats.jiffies_init)
143 		can_init_stats();
144 
145 	/* prevent overflow in calc_rate() */
146 	if (can_stats.rx_frames > (ULONG_MAX / HZ))
147 		can_init_stats();
148 
149 	/* prevent overflow in calc_rate() */
150 	if (can_stats.tx_frames > (ULONG_MAX / HZ))
151 		can_init_stats();
152 
153 	/* matches overflow - very improbable */
154 	if (can_stats.matches > (ULONG_MAX / 100))
155 		can_init_stats();
156 
157 	/* calc total values */
158 	if (can_stats.rx_frames)
159 		can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
160 			can_stats.rx_frames;
161 
162 	can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
163 					    can_stats.tx_frames);
164 	can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
165 					    can_stats.rx_frames);
166 
167 	/* calc current values */
168 	if (can_stats.rx_frames_delta)
169 		can_stats.current_rx_match_ratio =
170 			(can_stats.matches_delta * 100) /
171 			can_stats.rx_frames_delta;
172 
173 	can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
174 	can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);
175 
176 	/* check / update maximum values */
177 	if (can_stats.max_tx_rate < can_stats.current_tx_rate)
178 		can_stats.max_tx_rate = can_stats.current_tx_rate;
179 
180 	if (can_stats.max_rx_rate < can_stats.current_rx_rate)
181 		can_stats.max_rx_rate = can_stats.current_rx_rate;
182 
183 	if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
184 		can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;
185 
186 	/* clear values for 'current rate' calculation */
187 	can_stats.tx_frames_delta = 0;
188 	can_stats.rx_frames_delta = 0;
189 	can_stats.matches_delta   = 0;
190 
191 	/* restart timer (one second) */
192 	mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
193 }
194 
195 /*
196  * proc read functions
197  */
198 
199 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
200 			      struct net_device *dev)
201 {
202 	struct receiver *r;
203 	struct hlist_node *n;
204 
205 	hlist_for_each_entry_rcu(r, n, rx_list, list) {
206 		char *fmt = (r->can_id & CAN_EFF_FLAG)?
207 			"   %-5s  %08x  %08x  %pK  %pK  %8ld  %s\n" :
208 			"   %-5s     %03x    %08x  %pK  %pK  %8ld  %s\n";
209 
210 		seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
211 				r->func, r->data, r->matches, r->ident);
212 	}
213 }
214 
215 static void can_print_recv_banner(struct seq_file *m)
216 {
217 	/*
218 	 *                  can1.  00000000  00000000  00000000
219 	 *                 .......          0  tp20
220 	 */
221 	seq_puts(m, "  device   can_id   can_mask  function"
222 			"  userdata   matches  ident\n");
223 }
224 
225 static int can_stats_proc_show(struct seq_file *m, void *v)
226 {
227 	seq_putc(m, '\n');
228 	seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
229 	seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
230 	seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);
231 
232 	seq_putc(m, '\n');
233 
234 	if (can_stattimer.function == can_stat_update) {
235 		seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
236 				can_stats.total_rx_match_ratio);
237 
238 		seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
239 				can_stats.total_tx_rate);
240 		seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
241 				can_stats.total_rx_rate);
242 
243 		seq_putc(m, '\n');
244 
245 		seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
246 				can_stats.current_rx_match_ratio);
247 
248 		seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
249 				can_stats.current_tx_rate);
250 		seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
251 				can_stats.current_rx_rate);
252 
253 		seq_putc(m, '\n');
254 
255 		seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
256 				can_stats.max_rx_match_ratio);
257 
258 		seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
259 				can_stats.max_tx_rate);
260 		seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
261 				can_stats.max_rx_rate);
262 
263 		seq_putc(m, '\n');
264 	}
265 
266 	seq_printf(m, " %8ld current receive list entries (CRCV)\n",
267 			can_pstats.rcv_entries);
268 	seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
269 			can_pstats.rcv_entries_max);
270 
271 	if (can_pstats.stats_reset)
272 		seq_printf(m, "\n %8ld statistic resets (STR)\n",
273 				can_pstats.stats_reset);
274 
275 	if (can_pstats.user_reset)
276 		seq_printf(m, " %8ld user statistic resets (USTR)\n",
277 				can_pstats.user_reset);
278 
279 	seq_putc(m, '\n');
280 	return 0;
281 }
282 
283 static int can_stats_proc_open(struct inode *inode, struct file *file)
284 {
285 	return single_open(file, can_stats_proc_show, NULL);
286 }
287 
288 static const struct file_operations can_stats_proc_fops = {
289 	.owner		= THIS_MODULE,
290 	.open		= can_stats_proc_open,
291 	.read		= seq_read,
292 	.llseek		= seq_lseek,
293 	.release	= single_release,
294 };
295 
296 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
297 {
298 	user_reset = 1;
299 
300 	if (can_stattimer.function == can_stat_update) {
301 		seq_printf(m, "Scheduled statistic reset #%ld.\n",
302 				can_pstats.stats_reset + 1);
303 
304 	} else {
305 		if (can_stats.jiffies_init != jiffies)
306 			can_init_stats();
307 
308 		seq_printf(m, "Performed statistic reset #%ld.\n",
309 				can_pstats.stats_reset);
310 	}
311 	return 0;
312 }
313 
314 static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
315 {
316 	return single_open(file, can_reset_stats_proc_show, NULL);
317 }
318 
319 static const struct file_operations can_reset_stats_proc_fops = {
320 	.owner		= THIS_MODULE,
321 	.open		= can_reset_stats_proc_open,
322 	.read		= seq_read,
323 	.llseek		= seq_lseek,
324 	.release	= single_release,
325 };
326 
327 static int can_version_proc_show(struct seq_file *m, void *v)
328 {
329 	seq_printf(m, "%s\n", CAN_VERSION_STRING);
330 	return 0;
331 }
332 
333 static int can_version_proc_open(struct inode *inode, struct file *file)
334 {
335 	return single_open(file, can_version_proc_show, NULL);
336 }
337 
338 static const struct file_operations can_version_proc_fops = {
339 	.owner		= THIS_MODULE,
340 	.open		= can_version_proc_open,
341 	.read		= seq_read,
342 	.llseek		= seq_lseek,
343 	.release	= single_release,
344 };
345 
346 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
347 					     struct net_device *dev,
348 					     struct dev_rcv_lists *d)
349 {
350 	if (!hlist_empty(&d->rx[idx])) {
351 		can_print_recv_banner(m);
352 		can_print_rcvlist(m, &d->rx[idx], dev);
353 	} else
354 		seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
355 
356 }
357 
358 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
359 {
360 	/* double cast to prevent GCC warning */
361 	int idx = (int)(long)m->private;
362 	struct net_device *dev;
363 	struct dev_rcv_lists *d;
364 
365 	seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
366 
367 	rcu_read_lock();
368 
369 	/* receive list for 'all' CAN devices (dev == NULL) */
370 	d = &can_rx_alldev_list;
371 	can_rcvlist_proc_show_one(m, idx, NULL, d);
372 
373 	/* receive list for registered CAN devices */
374 	for_each_netdev_rcu(&init_net, dev) {
375 		if (dev->type == ARPHRD_CAN && dev->ml_priv)
376 			can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
377 	}
378 
379 	rcu_read_unlock();
380 
381 	seq_putc(m, '\n');
382 	return 0;
383 }
384 
385 static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
386 {
387 	return single_open(file, can_rcvlist_proc_show, PDE(inode)->data);
388 }
389 
390 static const struct file_operations can_rcvlist_proc_fops = {
391 	.owner		= THIS_MODULE,
392 	.open		= can_rcvlist_proc_open,
393 	.read		= seq_read,
394 	.llseek		= seq_lseek,
395 	.release	= single_release,
396 };
397 
398 static inline void can_rcvlist_sff_proc_show_one(struct seq_file *m,
399 						 struct net_device *dev,
400 						 struct dev_rcv_lists *d)
401 {
402 	int i;
403 	int all_empty = 1;
404 
405 	/* check wether at least one list is non-empty */
406 	for (i = 0; i < 0x800; i++)
407 		if (!hlist_empty(&d->rx_sff[i])) {
408 			all_empty = 0;
409 			break;
410 		}
411 
412 	if (!all_empty) {
413 		can_print_recv_banner(m);
414 		for (i = 0; i < 0x800; i++) {
415 			if (!hlist_empty(&d->rx_sff[i]))
416 				can_print_rcvlist(m, &d->rx_sff[i], dev);
417 		}
418 	} else
419 		seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
420 }
421 
422 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
423 {
424 	struct net_device *dev;
425 	struct dev_rcv_lists *d;
426 
427 	/* RX_SFF */
428 	seq_puts(m, "\nreceive list 'rx_sff':\n");
429 
430 	rcu_read_lock();
431 
432 	/* sff receive list for 'all' CAN devices (dev == NULL) */
433 	d = &can_rx_alldev_list;
434 	can_rcvlist_sff_proc_show_one(m, NULL, d);
435 
436 	/* sff receive list for registered CAN devices */
437 	for_each_netdev_rcu(&init_net, dev) {
438 		if (dev->type == ARPHRD_CAN && dev->ml_priv)
439 			can_rcvlist_sff_proc_show_one(m, dev, dev->ml_priv);
440 	}
441 
442 	rcu_read_unlock();
443 
444 	seq_putc(m, '\n');
445 	return 0;
446 }
447 
448 static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
449 {
450 	return single_open(file, can_rcvlist_sff_proc_show, NULL);
451 }
452 
453 static const struct file_operations can_rcvlist_sff_proc_fops = {
454 	.owner		= THIS_MODULE,
455 	.open		= can_rcvlist_sff_proc_open,
456 	.read		= seq_read,
457 	.llseek		= seq_lseek,
458 	.release	= single_release,
459 };
460 
461 /*
462  * proc utility functions
463  */
464 
465 static void can_remove_proc_readentry(const char *name)
466 {
467 	if (can_dir)
468 		remove_proc_entry(name, can_dir);
469 }
470 
471 /*
472  * can_init_proc - create main CAN proc directory and procfs entries
473  */
474 void can_init_proc(void)
475 {
476 	/* create /proc/net/can directory */
477 	can_dir = proc_mkdir("can", init_net.proc_net);
478 
479 	if (!can_dir) {
480 		printk(KERN_INFO "can: failed to create /proc/net/can . "
481 		       "CONFIG_PROC_FS missing?\n");
482 		return;
483 	}
484 
485 	/* own procfs entries from the AF_CAN core */
486 	pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
487 				      &can_version_proc_fops);
488 	pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
489 				      &can_stats_proc_fops);
490 	pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
491 				      &can_reset_stats_proc_fops);
492 	pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
493 					   &can_rcvlist_proc_fops, (void *)RX_ERR);
494 	pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
495 					   &can_rcvlist_proc_fops, (void *)RX_ALL);
496 	pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
497 					   &can_rcvlist_proc_fops, (void *)RX_FIL);
498 	pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
499 					   &can_rcvlist_proc_fops, (void *)RX_INV);
500 	pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
501 					   &can_rcvlist_proc_fops, (void *)RX_EFF);
502 	pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
503 				      &can_rcvlist_sff_proc_fops);
504 }
505 
506 /*
507  * can_remove_proc - remove procfs entries and main CAN proc directory
508  */
509 void can_remove_proc(void)
510 {
511 	if (pde_version)
512 		can_remove_proc_readentry(CAN_PROC_VERSION);
513 
514 	if (pde_stats)
515 		can_remove_proc_readentry(CAN_PROC_STATS);
516 
517 	if (pde_reset_stats)
518 		can_remove_proc_readentry(CAN_PROC_RESET_STATS);
519 
520 	if (pde_rcvlist_err)
521 		can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
522 
523 	if (pde_rcvlist_all)
524 		can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
525 
526 	if (pde_rcvlist_fil)
527 		can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
528 
529 	if (pde_rcvlist_inv)
530 		can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
531 
532 	if (pde_rcvlist_eff)
533 		can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
534 
535 	if (pde_rcvlist_sff)
536 		can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
537 
538 	if (can_dir)
539 		proc_net_remove(&init_net, "can");
540 }
541