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 = timer_container_of(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, atomic_long_read(&r->matches),
200 r->ident);
201 }
202 }
203
can_print_recv_banner(struct seq_file * m)204 static void can_print_recv_banner(struct seq_file *m)
205 {
206 /*
207 * can1. 00000000 00000000 00000000
208 * ....... 0 tp20
209 */
210 if (IS_ENABLED(CONFIG_64BIT))
211 seq_puts(m, " device can_id can_mask function userdata matches ident\n");
212 else
213 seq_puts(m, " device can_id can_mask function userdata matches ident\n");
214 }
215
can_stats_proc_show(struct seq_file * m,void * v)216 static int can_stats_proc_show(struct seq_file *m, void *v)
217 {
218 struct net *net = m->private;
219 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
220 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
221
222 seq_putc(m, '\n');
223 seq_printf(m, " %8ld transmitted frames (TXF)\n",
224 atomic_long_read(&pkg_stats->tx_frames));
225 seq_printf(m, " %8ld received frames (RXF)\n",
226 atomic_long_read(&pkg_stats->rx_frames));
227 seq_printf(m, " %8ld matched frames (RXMF)\n",
228 atomic_long_read(&pkg_stats->matches));
229
230 seq_putc(m, '\n');
231
232 if (net->can.stattimer.function == can_stat_update) {
233 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
234 pkg_stats->total_rx_match_ratio);
235
236 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
237 pkg_stats->total_tx_rate);
238 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
239 pkg_stats->total_rx_rate);
240
241 seq_putc(m, '\n');
242
243 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
244 pkg_stats->current_rx_match_ratio);
245
246 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
247 pkg_stats->current_tx_rate);
248 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
249 pkg_stats->current_rx_rate);
250
251 seq_putc(m, '\n');
252
253 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
254 pkg_stats->max_rx_match_ratio);
255
256 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
257 pkg_stats->max_tx_rate);
258 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
259 pkg_stats->max_rx_rate);
260
261 seq_putc(m, '\n');
262 }
263
264 seq_printf(m, " %8ld current receive list entries (CRCV)\n",
265 rcv_lists_stats->rcv_entries);
266 seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
267 rcv_lists_stats->rcv_entries_max);
268
269 if (rcv_lists_stats->stats_reset)
270 seq_printf(m, "\n %8ld statistic resets (STR)\n",
271 rcv_lists_stats->stats_reset);
272
273 if (rcv_lists_stats->user_reset)
274 seq_printf(m, " %8ld user statistic resets (USTR)\n",
275 rcv_lists_stats->user_reset);
276
277 seq_putc(m, '\n');
278 return 0;
279 }
280
can_reset_stats_proc_show(struct seq_file * m,void * v)281 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
282 {
283 struct net *net = m->private;
284 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
285 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
286
287 user_reset = 1;
288
289 if (net->can.stattimer.function == can_stat_update) {
290 seq_printf(m, "Scheduled statistic reset #%ld.\n",
291 rcv_lists_stats->stats_reset + 1);
292 } else {
293 if (pkg_stats->jiffies_init != jiffies)
294 can_init_stats(net);
295
296 seq_printf(m, "Performed statistic reset #%ld.\n",
297 rcv_lists_stats->stats_reset);
298 }
299 return 0;
300 }
301
can_rcvlist_proc_show_one(struct seq_file * m,int idx,struct net_device * dev,struct can_dev_rcv_lists * dev_rcv_lists)302 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
303 struct net_device *dev,
304 struct can_dev_rcv_lists *dev_rcv_lists)
305 {
306 if (!hlist_empty(&dev_rcv_lists->rx[idx])) {
307 can_print_recv_banner(m);
308 can_print_rcvlist(m, &dev_rcv_lists->rx[idx], dev);
309 } else
310 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
311
312 }
313
can_rcvlist_proc_show(struct seq_file * m,void * v)314 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
315 {
316 /* double cast to prevent GCC warning */
317 int idx = (int)(long)pde_data(m->file->f_inode);
318 struct net_device *dev;
319 struct can_dev_rcv_lists *dev_rcv_lists;
320 struct net *net = m->private;
321
322 seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
323
324 rcu_read_lock();
325
326 /* receive list for 'all' CAN devices (dev == NULL) */
327 dev_rcv_lists = net->can.rx_alldev_list;
328 can_rcvlist_proc_show_one(m, idx, NULL, dev_rcv_lists);
329
330 /* receive list for registered CAN devices */
331 for_each_netdev_rcu(net, dev) {
332 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
333
334 if (can_ml)
335 can_rcvlist_proc_show_one(m, idx, dev,
336 &can_ml->dev_rcv_lists);
337 }
338
339 rcu_read_unlock();
340
341 seq_putc(m, '\n');
342 return 0;
343 }
344
can_rcvlist_proc_show_array(struct seq_file * m,struct net_device * dev,struct hlist_head * rcv_array,unsigned int rcv_array_sz)345 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
346 struct net_device *dev,
347 struct hlist_head *rcv_array,
348 unsigned int rcv_array_sz)
349 {
350 unsigned int i;
351 int all_empty = 1;
352
353 /* check whether at least one list is non-empty */
354 for (i = 0; i < rcv_array_sz; i++)
355 if (!hlist_empty(&rcv_array[i])) {
356 all_empty = 0;
357 break;
358 }
359
360 if (!all_empty) {
361 can_print_recv_banner(m);
362 for (i = 0; i < rcv_array_sz; i++) {
363 if (!hlist_empty(&rcv_array[i]))
364 can_print_rcvlist(m, &rcv_array[i], dev);
365 }
366 } else
367 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
368 }
369
can_rcvlist_sff_proc_show(struct seq_file * m,void * v)370 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
371 {
372 struct net_device *dev;
373 struct can_dev_rcv_lists *dev_rcv_lists;
374 struct net *net = m->private;
375
376 /* RX_SFF */
377 seq_puts(m, "\nreceive list 'rx_sff':\n");
378
379 rcu_read_lock();
380
381 /* sff receive list for 'all' CAN devices (dev == NULL) */
382 dev_rcv_lists = net->can.rx_alldev_list;
383 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff,
384 ARRAY_SIZE(dev_rcv_lists->rx_sff));
385
386 /* sff receive list for registered CAN devices */
387 for_each_netdev_rcu(net, dev) {
388 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
389
390 if (can_ml) {
391 dev_rcv_lists = &can_ml->dev_rcv_lists;
392 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff,
393 ARRAY_SIZE(dev_rcv_lists->rx_sff));
394 }
395 }
396
397 rcu_read_unlock();
398
399 seq_putc(m, '\n');
400 return 0;
401 }
402
can_rcvlist_eff_proc_show(struct seq_file * m,void * v)403 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
404 {
405 struct net_device *dev;
406 struct can_dev_rcv_lists *dev_rcv_lists;
407 struct net *net = m->private;
408
409 /* RX_EFF */
410 seq_puts(m, "\nreceive list 'rx_eff':\n");
411
412 rcu_read_lock();
413
414 /* eff receive list for 'all' CAN devices (dev == NULL) */
415 dev_rcv_lists = net->can.rx_alldev_list;
416 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff,
417 ARRAY_SIZE(dev_rcv_lists->rx_eff));
418
419 /* eff receive list for registered CAN devices */
420 for_each_netdev_rcu(net, dev) {
421 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
422
423 if (can_ml) {
424 dev_rcv_lists = &can_ml->dev_rcv_lists;
425 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff,
426 ARRAY_SIZE(dev_rcv_lists->rx_eff));
427 }
428 }
429
430 rcu_read_unlock();
431
432 seq_putc(m, '\n');
433 return 0;
434 }
435
436 /*
437 * can_init_proc - create main CAN proc directory and procfs entries
438 */
can_init_proc(struct net * net)439 void can_init_proc(struct net *net)
440 {
441 /* create /proc/net/can directory */
442 net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
443
444 if (!net->can.proc_dir) {
445 printk(KERN_INFO "can: failed to create /proc/net/can . "
446 "CONFIG_PROC_FS missing?\n");
447 return;
448 }
449
450 /* own procfs entries from the AF_CAN core */
451 net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644,
452 net->can.proc_dir, can_stats_proc_show, NULL);
453 net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS,
454 0644, net->can.proc_dir, can_reset_stats_proc_show,
455 NULL);
456 net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR,
457 0644, net->can.proc_dir, can_rcvlist_proc_show,
458 (void *)RX_ERR);
459 net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL,
460 0644, net->can.proc_dir, can_rcvlist_proc_show,
461 (void *)RX_ALL);
462 net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL,
463 0644, net->can.proc_dir, can_rcvlist_proc_show,
464 (void *)RX_FIL);
465 net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV,
466 0644, net->can.proc_dir, can_rcvlist_proc_show,
467 (void *)RX_INV);
468 net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF,
469 0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL);
470 net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF,
471 0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL);
472 }
473
474 /*
475 * can_remove_proc - remove procfs entries and main CAN proc directory
476 */
can_remove_proc(struct net * net)477 void can_remove_proc(struct net *net)
478 {
479 if (!net->can.proc_dir)
480 return;
481
482 if (net->can.pde_stats)
483 remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
484
485 if (net->can.pde_reset_stats)
486 remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
487
488 if (net->can.pde_rcvlist_err)
489 remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
490
491 if (net->can.pde_rcvlist_all)
492 remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
493
494 if (net->can.pde_rcvlist_fil)
495 remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
496
497 if (net->can.pde_rcvlist_inv)
498 remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
499
500 if (net->can.pde_rcvlist_eff)
501 remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
502
503 if (net->can.pde_rcvlist_sff)
504 remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
505
506 remove_proc_entry("can", net->proc_net);
507 }
508