1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /*
3 * proc.c - procfs support for Protocol family CAN core module
4 *
5 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
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.
19 *
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, in which case the provisions of the
23 * GPL apply INSTEAD OF those given above.
24 *
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.
27 *
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
39 * DAMAGE.
40 *
41 */
42
43 #include <linux/module.h>
44 #include <linux/proc_fs.h>
45 #include <linux/list.h>
46 #include <linux/rcupdate.h>
47 #include <linux/if_arp.h>
48 #include <linux/can/can-ml.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_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
66 static int user_reset;
67
68 static const char rx_list_name[][8] = {
69 [RX_ERR] = "rx_err",
70 [RX_ALL] = "rx_all",
71 [RX_FIL] = "rx_fil",
72 [RX_INV] = "rx_inv",
73 };
74
75 /*
76 * af_can statistics stuff
77 */
78
can_init_stats(struct net * net)79 static void can_init_stats(struct net *net)
80 {
81 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
82 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
83 /*
84 * This memset function is called from a timer context (when
85 * can_stattimer is active which is the default) OR in a process
86 * context (reading the proc_fs when can_stattimer is disabled).
87 */
88 memset(pkg_stats, 0, sizeof(struct can_pkg_stats));
89 pkg_stats->jiffies_init = jiffies;
90
91 rcv_lists_stats->stats_reset++;
92
93 if (user_reset) {
94 user_reset = 0;
95 rcv_lists_stats->user_reset++;
96 }
97 }
98
calc_rate(unsigned long oldjif,unsigned long newjif,unsigned long count)99 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
100 unsigned long count)
101 {
102 if (oldjif == newjif)
103 return 0;
104
105 /* see can_stat_update() - this should NEVER happen! */
106 if (count > (ULONG_MAX / HZ)) {
107 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
108 count);
109 return 99999999;
110 }
111
112 return (count * HZ) / (newjif - oldjif);
113 }
114
can_stat_update(struct timer_list * t)115 void can_stat_update(struct timer_list *t)
116 {
117 struct net *net = from_timer(net, t, can.stattimer);
118 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
119 unsigned long j = jiffies; /* snapshot */
120
121 long rx_frames = atomic_long_read(&pkg_stats->rx_frames);
122 long tx_frames = atomic_long_read(&pkg_stats->tx_frames);
123 long matches = atomic_long_read(&pkg_stats->matches);
124 long rx_frames_delta = atomic_long_read(&pkg_stats->rx_frames_delta);
125 long tx_frames_delta = atomic_long_read(&pkg_stats->tx_frames_delta);
126 long matches_delta = atomic_long_read(&pkg_stats->matches_delta);
127
128 /* restart counting in timer context on user request */
129 if (user_reset)
130 can_init_stats(net);
131
132 /* restart counting on jiffies overflow */
133 if (j < pkg_stats->jiffies_init)
134 can_init_stats(net);
135
136 /* prevent overflow in calc_rate() */
137 if (rx_frames > (LONG_MAX / HZ))
138 can_init_stats(net);
139
140 /* prevent overflow in calc_rate() */
141 if (tx_frames > (LONG_MAX / HZ))
142 can_init_stats(net);
143
144 /* matches overflow - very improbable */
145 if (matches > (LONG_MAX / 100))
146 can_init_stats(net);
147
148 /* calc total values */
149 if (rx_frames)
150 pkg_stats->total_rx_match_ratio = (matches * 100) / rx_frames;
151
152 pkg_stats->total_tx_rate = calc_rate(pkg_stats->jiffies_init, j,
153 tx_frames);
154 pkg_stats->total_rx_rate = calc_rate(pkg_stats->jiffies_init, j,
155 rx_frames);
156
157 /* calc current values */
158 if (rx_frames_delta)
159 pkg_stats->current_rx_match_ratio =
160 (matches_delta * 100) / rx_frames_delta;
161
162 pkg_stats->current_tx_rate = calc_rate(0, HZ, tx_frames_delta);
163 pkg_stats->current_rx_rate = calc_rate(0, HZ, rx_frames_delta);
164
165 /* check / update maximum values */
166 if (pkg_stats->max_tx_rate < pkg_stats->current_tx_rate)
167 pkg_stats->max_tx_rate = pkg_stats->current_tx_rate;
168
169 if (pkg_stats->max_rx_rate < pkg_stats->current_rx_rate)
170 pkg_stats->max_rx_rate = pkg_stats->current_rx_rate;
171
172 if (pkg_stats->max_rx_match_ratio < pkg_stats->current_rx_match_ratio)
173 pkg_stats->max_rx_match_ratio = pkg_stats->current_rx_match_ratio;
174
175 /* clear values for 'current rate' calculation */
176 atomic_long_set(&pkg_stats->tx_frames_delta, 0);
177 atomic_long_set(&pkg_stats->rx_frames_delta, 0);
178 atomic_long_set(&pkg_stats->matches_delta, 0);
179
180 /* restart timer (one second) */
181 mod_timer(&net->can.stattimer, round_jiffies(jiffies + HZ));
182 }
183
184 /*
185 * proc read functions
186 */
187
can_print_rcvlist(struct seq_file * m,struct hlist_head * rx_list,struct net_device * dev)188 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
189 struct net_device *dev)
190 {
191 struct receiver *r;
192
193 hlist_for_each_entry_rcu(r, rx_list, list) {
194 char *fmt = (r->can_id & CAN_EFF_FLAG)?
195 " %-5s %08x %08x %pK %pK %8ld %s\n" :
196 " %-5s %03x %08x %pK %pK %8ld %s\n";
197
198 seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
199 r->func, r->data, r->matches, r->ident);
200 }
201 }
202
can_print_recv_banner(struct seq_file * m)203 static void can_print_recv_banner(struct seq_file *m)
204 {
205 /*
206 * can1. 00000000 00000000 00000000
207 * ....... 0 tp20
208 */
209 if (IS_ENABLED(CONFIG_64BIT))
210 seq_puts(m, " device can_id can_mask function userdata matches ident\n");
211 else
212 seq_puts(m, " device can_id can_mask function userdata matches ident\n");
213 }
214
can_stats_proc_show(struct seq_file * m,void * v)215 static int can_stats_proc_show(struct seq_file *m, void *v)
216 {
217 struct net *net = m->private;
218 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
219 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
220
221 seq_putc(m, '\n');
222 seq_printf(m, " %8ld transmitted frames (TXF)\n",
223 atomic_long_read(&pkg_stats->tx_frames));
224 seq_printf(m, " %8ld received frames (RXF)\n",
225 atomic_long_read(&pkg_stats->rx_frames));
226 seq_printf(m, " %8ld matched frames (RXMF)\n",
227 atomic_long_read(&pkg_stats->matches));
228
229 seq_putc(m, '\n');
230
231 if (net->can.stattimer.function == can_stat_update) {
232 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
233 pkg_stats->total_rx_match_ratio);
234
235 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
236 pkg_stats->total_tx_rate);
237 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
238 pkg_stats->total_rx_rate);
239
240 seq_putc(m, '\n');
241
242 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
243 pkg_stats->current_rx_match_ratio);
244
245 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
246 pkg_stats->current_tx_rate);
247 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
248 pkg_stats->current_rx_rate);
249
250 seq_putc(m, '\n');
251
252 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
253 pkg_stats->max_rx_match_ratio);
254
255 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
256 pkg_stats->max_tx_rate);
257 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
258 pkg_stats->max_rx_rate);
259
260 seq_putc(m, '\n');
261 }
262
263 seq_printf(m, " %8ld current receive list entries (CRCV)\n",
264 rcv_lists_stats->rcv_entries);
265 seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
266 rcv_lists_stats->rcv_entries_max);
267
268 if (rcv_lists_stats->stats_reset)
269 seq_printf(m, "\n %8ld statistic resets (STR)\n",
270 rcv_lists_stats->stats_reset);
271
272 if (rcv_lists_stats->user_reset)
273 seq_printf(m, " %8ld user statistic resets (USTR)\n",
274 rcv_lists_stats->user_reset);
275
276 seq_putc(m, '\n');
277 return 0;
278 }
279
can_reset_stats_proc_show(struct seq_file * m,void * v)280 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
281 {
282 struct net *net = m->private;
283 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
284 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
285
286 user_reset = 1;
287
288 if (net->can.stattimer.function == can_stat_update) {
289 seq_printf(m, "Scheduled statistic reset #%ld.\n",
290 rcv_lists_stats->stats_reset + 1);
291 } else {
292 if (pkg_stats->jiffies_init != jiffies)
293 can_init_stats(net);
294
295 seq_printf(m, "Performed statistic reset #%ld.\n",
296 rcv_lists_stats->stats_reset);
297 }
298 return 0;
299 }
300
can_rcvlist_proc_show_one(struct seq_file * m,int idx,struct net_device * dev,struct can_dev_rcv_lists * dev_rcv_lists)301 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
302 struct net_device *dev,
303 struct can_dev_rcv_lists *dev_rcv_lists)
304 {
305 if (!hlist_empty(&dev_rcv_lists->rx[idx])) {
306 can_print_recv_banner(m);
307 can_print_rcvlist(m, &dev_rcv_lists->rx[idx], dev);
308 } else
309 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
310
311 }
312
can_rcvlist_proc_show(struct seq_file * m,void * v)313 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
314 {
315 /* double cast to prevent GCC warning */
316 int idx = (int)(long)pde_data(m->file->f_inode);
317 struct net_device *dev;
318 struct can_dev_rcv_lists *dev_rcv_lists;
319 struct net *net = m->private;
320
321 seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
322
323 rcu_read_lock();
324
325 /* receive list for 'all' CAN devices (dev == NULL) */
326 dev_rcv_lists = net->can.rx_alldev_list;
327 can_rcvlist_proc_show_one(m, idx, NULL, dev_rcv_lists);
328
329 /* receive list for registered CAN devices */
330 for_each_netdev_rcu(net, dev) {
331 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
332
333 if (can_ml)
334 can_rcvlist_proc_show_one(m, idx, dev,
335 &can_ml->dev_rcv_lists);
336 }
337
338 rcu_read_unlock();
339
340 seq_putc(m, '\n');
341 return 0;
342 }
343
can_rcvlist_proc_show_array(struct seq_file * m,struct net_device * dev,struct hlist_head * rcv_array,unsigned int rcv_array_sz)344 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
345 struct net_device *dev,
346 struct hlist_head *rcv_array,
347 unsigned int rcv_array_sz)
348 {
349 unsigned int i;
350 int all_empty = 1;
351
352 /* check whether at least one list is non-empty */
353 for (i = 0; i < rcv_array_sz; i++)
354 if (!hlist_empty(&rcv_array[i])) {
355 all_empty = 0;
356 break;
357 }
358
359 if (!all_empty) {
360 can_print_recv_banner(m);
361 for (i = 0; i < rcv_array_sz; i++) {
362 if (!hlist_empty(&rcv_array[i]))
363 can_print_rcvlist(m, &rcv_array[i], dev);
364 }
365 } else
366 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
367 }
368
can_rcvlist_sff_proc_show(struct seq_file * m,void * v)369 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
370 {
371 struct net_device *dev;
372 struct can_dev_rcv_lists *dev_rcv_lists;
373 struct net *net = m->private;
374
375 /* RX_SFF */
376 seq_puts(m, "\nreceive list 'rx_sff':\n");
377
378 rcu_read_lock();
379
380 /* sff receive list for 'all' CAN devices (dev == NULL) */
381 dev_rcv_lists = net->can.rx_alldev_list;
382 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff,
383 ARRAY_SIZE(dev_rcv_lists->rx_sff));
384
385 /* sff receive list for registered CAN devices */
386 for_each_netdev_rcu(net, dev) {
387 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
388
389 if (can_ml) {
390 dev_rcv_lists = &can_ml->dev_rcv_lists;
391 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff,
392 ARRAY_SIZE(dev_rcv_lists->rx_sff));
393 }
394 }
395
396 rcu_read_unlock();
397
398 seq_putc(m, '\n');
399 return 0;
400 }
401
can_rcvlist_eff_proc_show(struct seq_file * m,void * v)402 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
403 {
404 struct net_device *dev;
405 struct can_dev_rcv_lists *dev_rcv_lists;
406 struct net *net = m->private;
407
408 /* RX_EFF */
409 seq_puts(m, "\nreceive list 'rx_eff':\n");
410
411 rcu_read_lock();
412
413 /* eff receive list for 'all' CAN devices (dev == NULL) */
414 dev_rcv_lists = net->can.rx_alldev_list;
415 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff,
416 ARRAY_SIZE(dev_rcv_lists->rx_eff));
417
418 /* eff receive list for registered CAN devices */
419 for_each_netdev_rcu(net, dev) {
420 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
421
422 if (can_ml) {
423 dev_rcv_lists = &can_ml->dev_rcv_lists;
424 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff,
425 ARRAY_SIZE(dev_rcv_lists->rx_eff));
426 }
427 }
428
429 rcu_read_unlock();
430
431 seq_putc(m, '\n');
432 return 0;
433 }
434
435 /*
436 * can_init_proc - create main CAN proc directory and procfs entries
437 */
can_init_proc(struct net * net)438 void can_init_proc(struct net *net)
439 {
440 /* create /proc/net/can directory */
441 net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
442
443 if (!net->can.proc_dir) {
444 printk(KERN_INFO "can: failed to create /proc/net/can . "
445 "CONFIG_PROC_FS missing?\n");
446 return;
447 }
448
449 /* own procfs entries from the AF_CAN core */
450 net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644,
451 net->can.proc_dir, can_stats_proc_show, NULL);
452 net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS,
453 0644, net->can.proc_dir, can_reset_stats_proc_show,
454 NULL);
455 net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR,
456 0644, net->can.proc_dir, can_rcvlist_proc_show,
457 (void *)RX_ERR);
458 net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL,
459 0644, net->can.proc_dir, can_rcvlist_proc_show,
460 (void *)RX_ALL);
461 net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL,
462 0644, net->can.proc_dir, can_rcvlist_proc_show,
463 (void *)RX_FIL);
464 net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV,
465 0644, net->can.proc_dir, can_rcvlist_proc_show,
466 (void *)RX_INV);
467 net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF,
468 0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL);
469 net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF,
470 0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL);
471 }
472
473 /*
474 * can_remove_proc - remove procfs entries and main CAN proc directory
475 */
can_remove_proc(struct net * net)476 void can_remove_proc(struct net *net)
477 {
478 if (!net->can.proc_dir)
479 return;
480
481 if (net->can.pde_stats)
482 remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
483
484 if (net->can.pde_reset_stats)
485 remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
486
487 if (net->can.pde_rcvlist_err)
488 remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
489
490 if (net->can.pde_rcvlist_all)
491 remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
492
493 if (net->can.pde_rcvlist_fil)
494 remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
495
496 if (net->can.pde_rcvlist_inv)
497 remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
498
499 if (net->can.pde_rcvlist_eff)
500 remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
501
502 if (net->can.pde_rcvlist_sff)
503 remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
504
505 remove_proc_entry("can", net->proc_net);
506 }
507