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
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
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
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 /* restart counting in timer context on user request */
122 if (user_reset)
123 can_init_stats(net);
124
125 /* restart counting on jiffies overflow */
126 if (j < pkg_stats->jiffies_init)
127 can_init_stats(net);
128
129 /* prevent overflow in calc_rate() */
130 if (pkg_stats->rx_frames > (ULONG_MAX / HZ))
131 can_init_stats(net);
132
133 /* prevent overflow in calc_rate() */
134 if (pkg_stats->tx_frames > (ULONG_MAX / HZ))
135 can_init_stats(net);
136
137 /* matches overflow - very improbable */
138 if (pkg_stats->matches > (ULONG_MAX / 100))
139 can_init_stats(net);
140
141 /* calc total values */
142 if (pkg_stats->rx_frames)
143 pkg_stats->total_rx_match_ratio = (pkg_stats->matches * 100) /
144 pkg_stats->rx_frames;
145
146 pkg_stats->total_tx_rate = calc_rate(pkg_stats->jiffies_init, j,
147 pkg_stats->tx_frames);
148 pkg_stats->total_rx_rate = calc_rate(pkg_stats->jiffies_init, j,
149 pkg_stats->rx_frames);
150
151 /* calc current values */
152 if (pkg_stats->rx_frames_delta)
153 pkg_stats->current_rx_match_ratio =
154 (pkg_stats->matches_delta * 100) /
155 pkg_stats->rx_frames_delta;
156
157 pkg_stats->current_tx_rate = calc_rate(0, HZ, pkg_stats->tx_frames_delta);
158 pkg_stats->current_rx_rate = calc_rate(0, HZ, pkg_stats->rx_frames_delta);
159
160 /* check / update maximum values */
161 if (pkg_stats->max_tx_rate < pkg_stats->current_tx_rate)
162 pkg_stats->max_tx_rate = pkg_stats->current_tx_rate;
163
164 if (pkg_stats->max_rx_rate < pkg_stats->current_rx_rate)
165 pkg_stats->max_rx_rate = pkg_stats->current_rx_rate;
166
167 if (pkg_stats->max_rx_match_ratio < pkg_stats->current_rx_match_ratio)
168 pkg_stats->max_rx_match_ratio = pkg_stats->current_rx_match_ratio;
169
170 /* clear values for 'current rate' calculation */
171 pkg_stats->tx_frames_delta = 0;
172 pkg_stats->rx_frames_delta = 0;
173 pkg_stats->matches_delta = 0;
174
175 /* restart timer (one second) */
176 mod_timer(&net->can.stattimer, round_jiffies(jiffies + HZ));
177 }
178
179 /*
180 * proc read functions
181 */
182
183 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
184 struct net_device *dev)
185 {
186 struct receiver *r;
187
188 hlist_for_each_entry_rcu(r, rx_list, list) {
189 char *fmt = (r->can_id & CAN_EFF_FLAG)?
190 " %-5s %08x %08x %pK %pK %8ld %s\n" :
191 " %-5s %03x %08x %pK %pK %8ld %s\n";
192
193 seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
194 r->func, r->data, r->matches, r->ident);
195 }
196 }
197
198 static void can_print_recv_banner(struct seq_file *m)
199 {
200 /*
201 * can1. 00000000 00000000 00000000
202 * ....... 0 tp20
203 */
204 if (IS_ENABLED(CONFIG_64BIT))
205 seq_puts(m, " device can_id can_mask function userdata matches ident\n");
206 else
207 seq_puts(m, " device can_id can_mask function userdata matches ident\n");
208 }
209
210 static int can_stats_proc_show(struct seq_file *m, void *v)
211 {
212 struct net *net = m->private;
213 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
214 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
215
216 seq_putc(m, '\n');
217 seq_printf(m, " %8ld transmitted frames (TXF)\n", pkg_stats->tx_frames);
218 seq_printf(m, " %8ld received frames (RXF)\n", pkg_stats->rx_frames);
219 seq_printf(m, " %8ld matched frames (RXMF)\n", pkg_stats->matches);
220
221 seq_putc(m, '\n');
222
223 if (net->can.stattimer.function == can_stat_update) {
224 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
225 pkg_stats->total_rx_match_ratio);
226
227 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
228 pkg_stats->total_tx_rate);
229 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
230 pkg_stats->total_rx_rate);
231
232 seq_putc(m, '\n');
233
234 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
235 pkg_stats->current_rx_match_ratio);
236
237 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
238 pkg_stats->current_tx_rate);
239 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
240 pkg_stats->current_rx_rate);
241
242 seq_putc(m, '\n');
243
244 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
245 pkg_stats->max_rx_match_ratio);
246
247 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
248 pkg_stats->max_tx_rate);
249 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
250 pkg_stats->max_rx_rate);
251
252 seq_putc(m, '\n');
253 }
254
255 seq_printf(m, " %8ld current receive list entries (CRCV)\n",
256 rcv_lists_stats->rcv_entries);
257 seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
258 rcv_lists_stats->rcv_entries_max);
259
260 if (rcv_lists_stats->stats_reset)
261 seq_printf(m, "\n %8ld statistic resets (STR)\n",
262 rcv_lists_stats->stats_reset);
263
264 if (rcv_lists_stats->user_reset)
265 seq_printf(m, " %8ld user statistic resets (USTR)\n",
266 rcv_lists_stats->user_reset);
267
268 seq_putc(m, '\n');
269 return 0;
270 }
271
272 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
273 {
274 struct net *net = m->private;
275 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
276 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
277
278 user_reset = 1;
279
280 if (net->can.stattimer.function == can_stat_update) {
281 seq_printf(m, "Scheduled statistic reset #%ld.\n",
282 rcv_lists_stats->stats_reset + 1);
283 } else {
284 if (pkg_stats->jiffies_init != jiffies)
285 can_init_stats(net);
286
287 seq_printf(m, "Performed statistic reset #%ld.\n",
288 rcv_lists_stats->stats_reset);
289 }
290 return 0;
291 }
292
293 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
294 struct net_device *dev,
295 struct can_dev_rcv_lists *dev_rcv_lists)
296 {
297 if (!hlist_empty(&dev_rcv_lists->rx[idx])) {
298 can_print_recv_banner(m);
299 can_print_rcvlist(m, &dev_rcv_lists->rx[idx], dev);
300 } else
301 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
302
303 }
304
305 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
306 {
307 /* double cast to prevent GCC warning */
308 int idx = (int)(long)pde_data(m->file->f_inode);
309 struct net_device *dev;
310 struct can_dev_rcv_lists *dev_rcv_lists;
311 struct net *net = m->private;
312
313 seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
314
315 rcu_read_lock();
316
317 /* receive list for 'all' CAN devices (dev == NULL) */
318 dev_rcv_lists = net->can.rx_alldev_list;
319 can_rcvlist_proc_show_one(m, idx, NULL, dev_rcv_lists);
320
321 /* receive list for registered CAN devices */
322 for_each_netdev_rcu(net, dev) {
323 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
324
325 if (can_ml)
326 can_rcvlist_proc_show_one(m, idx, dev,
327 &can_ml->dev_rcv_lists);
328 }
329
330 rcu_read_unlock();
331
332 seq_putc(m, '\n');
333 return 0;
334 }
335
336 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
337 struct net_device *dev,
338 struct hlist_head *rcv_array,
339 unsigned int rcv_array_sz)
340 {
341 unsigned int i;
342 int all_empty = 1;
343
344 /* check whether at least one list is non-empty */
345 for (i = 0; i < rcv_array_sz; i++)
346 if (!hlist_empty(&rcv_array[i])) {
347 all_empty = 0;
348 break;
349 }
350
351 if (!all_empty) {
352 can_print_recv_banner(m);
353 for (i = 0; i < rcv_array_sz; i++) {
354 if (!hlist_empty(&rcv_array[i]))
355 can_print_rcvlist(m, &rcv_array[i], dev);
356 }
357 } else
358 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
359 }
360
361 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
362 {
363 struct net_device *dev;
364 struct can_dev_rcv_lists *dev_rcv_lists;
365 struct net *net = m->private;
366
367 /* RX_SFF */
368 seq_puts(m, "\nreceive list 'rx_sff':\n");
369
370 rcu_read_lock();
371
372 /* sff receive list for 'all' CAN devices (dev == NULL) */
373 dev_rcv_lists = net->can.rx_alldev_list;
374 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff,
375 ARRAY_SIZE(dev_rcv_lists->rx_sff));
376
377 /* sff receive list for registered CAN devices */
378 for_each_netdev_rcu(net, dev) {
379 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
380
381 if (can_ml) {
382 dev_rcv_lists = &can_ml->dev_rcv_lists;
383 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff,
384 ARRAY_SIZE(dev_rcv_lists->rx_sff));
385 }
386 }
387
388 rcu_read_unlock();
389
390 seq_putc(m, '\n');
391 return 0;
392 }
393
394 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
395 {
396 struct net_device *dev;
397 struct can_dev_rcv_lists *dev_rcv_lists;
398 struct net *net = m->private;
399
400 /* RX_EFF */
401 seq_puts(m, "\nreceive list 'rx_eff':\n");
402
403 rcu_read_lock();
404
405 /* eff receive list for 'all' CAN devices (dev == NULL) */
406 dev_rcv_lists = net->can.rx_alldev_list;
407 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff,
408 ARRAY_SIZE(dev_rcv_lists->rx_eff));
409
410 /* eff receive list for registered CAN devices */
411 for_each_netdev_rcu(net, dev) {
412 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
413
414 if (can_ml) {
415 dev_rcv_lists = &can_ml->dev_rcv_lists;
416 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff,
417 ARRAY_SIZE(dev_rcv_lists->rx_eff));
418 }
419 }
420
421 rcu_read_unlock();
422
423 seq_putc(m, '\n');
424 return 0;
425 }
426
427 /*
428 * can_init_proc - create main CAN proc directory and procfs entries
429 */
430 void can_init_proc(struct net *net)
431 {
432 /* create /proc/net/can directory */
433 net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
434
435 if (!net->can.proc_dir) {
436 printk(KERN_INFO "can: failed to create /proc/net/can . "
437 "CONFIG_PROC_FS missing?\n");
438 return;
439 }
440
441 /* own procfs entries from the AF_CAN core */
442 net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644,
443 net->can.proc_dir, can_stats_proc_show, NULL);
444 net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS,
445 0644, net->can.proc_dir, can_reset_stats_proc_show,
446 NULL);
447 net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR,
448 0644, net->can.proc_dir, can_rcvlist_proc_show,
449 (void *)RX_ERR);
450 net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL,
451 0644, net->can.proc_dir, can_rcvlist_proc_show,
452 (void *)RX_ALL);
453 net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL,
454 0644, net->can.proc_dir, can_rcvlist_proc_show,
455 (void *)RX_FIL);
456 net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV,
457 0644, net->can.proc_dir, can_rcvlist_proc_show,
458 (void *)RX_INV);
459 net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF,
460 0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL);
461 net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF,
462 0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL);
463 }
464
465 /*
466 * can_remove_proc - remove procfs entries and main CAN proc directory
467 */
468 void can_remove_proc(struct net *net)
469 {
470 if (!net->can.proc_dir)
471 return;
472
473 if (net->can.pde_stats)
474 remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
475
476 if (net->can.pde_reset_stats)
477 remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
478
479 if (net->can.pde_rcvlist_err)
480 remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
481
482 if (net->can.pde_rcvlist_all)
483 remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
484
485 if (net->can.pde_rcvlist_fil)
486 remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
487
488 if (net->can.pde_rcvlist_inv)
489 remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
490
491 if (net->can.pde_rcvlist_eff)
492 remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
493
494 if (net->can.pde_rcvlist_sff)
495 remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
496
497 remove_proc_entry("can", net->proc_net);
498 }
499
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