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 unsigned long rate;
103
104 if (oldjif == newjif)
105 return 0;
106
107 /* see can_stat_update() - this should NEVER happen! */
108 if (count > (ULONG_MAX / HZ)) {
109 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
110 count);
111 return 99999999;
112 }
113
114 rate = (count * HZ) / (newjif - oldjif);
115
116 return rate;
117 }
118
can_stat_update(struct timer_list * t)119 void can_stat_update(struct timer_list *t)
120 {
121 struct net *net = from_timer(net, t, can.stattimer);
122 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
123 unsigned long j = jiffies; /* snapshot */
124
125 /* restart counting in timer context on user request */
126 if (user_reset)
127 can_init_stats(net);
128
129 /* restart counting on jiffies overflow */
130 if (j < pkg_stats->jiffies_init)
131 can_init_stats(net);
132
133 /* prevent overflow in calc_rate() */
134 if (pkg_stats->rx_frames > (ULONG_MAX / HZ))
135 can_init_stats(net);
136
137 /* prevent overflow in calc_rate() */
138 if (pkg_stats->tx_frames > (ULONG_MAX / HZ))
139 can_init_stats(net);
140
141 /* matches overflow - very improbable */
142 if (pkg_stats->matches > (ULONG_MAX / 100))
143 can_init_stats(net);
144
145 /* calc total values */
146 if (pkg_stats->rx_frames)
147 pkg_stats->total_rx_match_ratio = (pkg_stats->matches * 100) /
148 pkg_stats->rx_frames;
149
150 pkg_stats->total_tx_rate = calc_rate(pkg_stats->jiffies_init, j,
151 pkg_stats->tx_frames);
152 pkg_stats->total_rx_rate = calc_rate(pkg_stats->jiffies_init, j,
153 pkg_stats->rx_frames);
154
155 /* calc current values */
156 if (pkg_stats->rx_frames_delta)
157 pkg_stats->current_rx_match_ratio =
158 (pkg_stats->matches_delta * 100) /
159 pkg_stats->rx_frames_delta;
160
161 pkg_stats->current_tx_rate = calc_rate(0, HZ, pkg_stats->tx_frames_delta);
162 pkg_stats->current_rx_rate = calc_rate(0, HZ, pkg_stats->rx_frames_delta);
163
164 /* check / update maximum values */
165 if (pkg_stats->max_tx_rate < pkg_stats->current_tx_rate)
166 pkg_stats->max_tx_rate = pkg_stats->current_tx_rate;
167
168 if (pkg_stats->max_rx_rate < pkg_stats->current_rx_rate)
169 pkg_stats->max_rx_rate = pkg_stats->current_rx_rate;
170
171 if (pkg_stats->max_rx_match_ratio < pkg_stats->current_rx_match_ratio)
172 pkg_stats->max_rx_match_ratio = pkg_stats->current_rx_match_ratio;
173
174 /* clear values for 'current rate' calculation */
175 pkg_stats->tx_frames_delta = 0;
176 pkg_stats->rx_frames_delta = 0;
177 pkg_stats->matches_delta = 0;
178
179 /* restart timer (one second) */
180 mod_timer(&net->can.stattimer, round_jiffies(jiffies + HZ));
181 }
182
183 /*
184 * proc read functions
185 */
186
can_print_rcvlist(struct seq_file * m,struct hlist_head * rx_list,struct net_device * dev)187 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
188 struct net_device *dev)
189 {
190 struct receiver *r;
191
192 hlist_for_each_entry_rcu(r, rx_list, list) {
193 char *fmt = (r->can_id & CAN_EFF_FLAG)?
194 " %-5s %08x %08x %pK %pK %8ld %s\n" :
195 " %-5s %03x %08x %pK %pK %8ld %s\n";
196
197 seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
198 r->func, r->data, r->matches, r->ident);
199 }
200 }
201
can_print_recv_banner(struct seq_file * m)202 static void can_print_recv_banner(struct seq_file *m)
203 {
204 /*
205 * can1. 00000000 00000000 00000000
206 * ....... 0 tp20
207 */
208 seq_puts(m, " device can_id can_mask function"
209 " userdata matches ident\n");
210 }
211
can_stats_proc_show(struct seq_file * m,void * v)212 static int can_stats_proc_show(struct seq_file *m, void *v)
213 {
214 struct net *net = m->private;
215 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
216 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
217
218 seq_putc(m, '\n');
219 seq_printf(m, " %8ld transmitted frames (TXF)\n", pkg_stats->tx_frames);
220 seq_printf(m, " %8ld received frames (RXF)\n", pkg_stats->rx_frames);
221 seq_printf(m, " %8ld matched frames (RXMF)\n", pkg_stats->matches);
222
223 seq_putc(m, '\n');
224
225 if (net->can.stattimer.function == can_stat_update) {
226 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
227 pkg_stats->total_rx_match_ratio);
228
229 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
230 pkg_stats->total_tx_rate);
231 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
232 pkg_stats->total_rx_rate);
233
234 seq_putc(m, '\n');
235
236 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
237 pkg_stats->current_rx_match_ratio);
238
239 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
240 pkg_stats->current_tx_rate);
241 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
242 pkg_stats->current_rx_rate);
243
244 seq_putc(m, '\n');
245
246 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
247 pkg_stats->max_rx_match_ratio);
248
249 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
250 pkg_stats->max_tx_rate);
251 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
252 pkg_stats->max_rx_rate);
253
254 seq_putc(m, '\n');
255 }
256
257 seq_printf(m, " %8ld current receive list entries (CRCV)\n",
258 rcv_lists_stats->rcv_entries);
259 seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
260 rcv_lists_stats->rcv_entries_max);
261
262 if (rcv_lists_stats->stats_reset)
263 seq_printf(m, "\n %8ld statistic resets (STR)\n",
264 rcv_lists_stats->stats_reset);
265
266 if (rcv_lists_stats->user_reset)
267 seq_printf(m, " %8ld user statistic resets (USTR)\n",
268 rcv_lists_stats->user_reset);
269
270 seq_putc(m, '\n');
271 return 0;
272 }
273
can_reset_stats_proc_show(struct seq_file * m,void * v)274 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
275 {
276 struct net *net = m->private;
277 struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
278 struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
279
280 user_reset = 1;
281
282 if (net->can.stattimer.function == can_stat_update) {
283 seq_printf(m, "Scheduled statistic reset #%ld.\n",
284 rcv_lists_stats->stats_reset + 1);
285 } else {
286 if (pkg_stats->jiffies_init != jiffies)
287 can_init_stats(net);
288
289 seq_printf(m, "Performed statistic reset #%ld.\n",
290 rcv_lists_stats->stats_reset);
291 }
292 return 0;
293 }
294
can_rcvlist_proc_show_one(struct seq_file * m,int idx,struct net_device * dev,struct can_dev_rcv_lists * dev_rcv_lists)295 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
296 struct net_device *dev,
297 struct can_dev_rcv_lists *dev_rcv_lists)
298 {
299 if (!hlist_empty(&dev_rcv_lists->rx[idx])) {
300 can_print_recv_banner(m);
301 can_print_rcvlist(m, &dev_rcv_lists->rx[idx], dev);
302 } else
303 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
304
305 }
306
can_rcvlist_proc_show(struct seq_file * m,void * v)307 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
308 {
309 /* double cast to prevent GCC warning */
310 int idx = (int)(long)PDE_DATA(m->file->f_inode);
311 struct net_device *dev;
312 struct can_dev_rcv_lists *dev_rcv_lists;
313 struct net *net = m->private;
314
315 seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
316
317 rcu_read_lock();
318
319 /* receive list for 'all' CAN devices (dev == NULL) */
320 dev_rcv_lists = net->can.rx_alldev_list;
321 can_rcvlist_proc_show_one(m, idx, NULL, dev_rcv_lists);
322
323 /* receive list for registered CAN devices */
324 for_each_netdev_rcu(net, dev) {
325 if (dev->type == ARPHRD_CAN && dev->ml_priv)
326 can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
327 }
328
329 rcu_read_unlock();
330
331 seq_putc(m, '\n');
332 return 0;
333 }
334
can_rcvlist_proc_show_array(struct seq_file * m,struct net_device * dev,struct hlist_head * rcv_array,unsigned int rcv_array_sz)335 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
336 struct net_device *dev,
337 struct hlist_head *rcv_array,
338 unsigned int rcv_array_sz)
339 {
340 unsigned int i;
341 int all_empty = 1;
342
343 /* check whether at least one list is non-empty */
344 for (i = 0; i < rcv_array_sz; i++)
345 if (!hlist_empty(&rcv_array[i])) {
346 all_empty = 0;
347 break;
348 }
349
350 if (!all_empty) {
351 can_print_recv_banner(m);
352 for (i = 0; i < rcv_array_sz; i++) {
353 if (!hlist_empty(&rcv_array[i]))
354 can_print_rcvlist(m, &rcv_array[i], dev);
355 }
356 } else
357 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
358 }
359
can_rcvlist_sff_proc_show(struct seq_file * m,void * v)360 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
361 {
362 struct net_device *dev;
363 struct can_dev_rcv_lists *dev_rcv_lists;
364 struct net *net = m->private;
365
366 /* RX_SFF */
367 seq_puts(m, "\nreceive list 'rx_sff':\n");
368
369 rcu_read_lock();
370
371 /* sff receive list for 'all' CAN devices (dev == NULL) */
372 dev_rcv_lists = net->can.rx_alldev_list;
373 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff,
374 ARRAY_SIZE(dev_rcv_lists->rx_sff));
375
376 /* sff receive list for registered CAN devices */
377 for_each_netdev_rcu(net, dev) {
378 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
379 dev_rcv_lists = dev->ml_priv;
380 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff,
381 ARRAY_SIZE(dev_rcv_lists->rx_sff));
382 }
383 }
384
385 rcu_read_unlock();
386
387 seq_putc(m, '\n');
388 return 0;
389 }
390
can_rcvlist_eff_proc_show(struct seq_file * m,void * v)391 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
392 {
393 struct net_device *dev;
394 struct can_dev_rcv_lists *dev_rcv_lists;
395 struct net *net = m->private;
396
397 /* RX_EFF */
398 seq_puts(m, "\nreceive list 'rx_eff':\n");
399
400 rcu_read_lock();
401
402 /* eff receive list for 'all' CAN devices (dev == NULL) */
403 dev_rcv_lists = net->can.rx_alldev_list;
404 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff,
405 ARRAY_SIZE(dev_rcv_lists->rx_eff));
406
407 /* eff receive list for registered CAN devices */
408 for_each_netdev_rcu(net, dev) {
409 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
410 dev_rcv_lists = dev->ml_priv;
411 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff,
412 ARRAY_SIZE(dev_rcv_lists->rx_eff));
413 }
414 }
415
416 rcu_read_unlock();
417
418 seq_putc(m, '\n');
419 return 0;
420 }
421
422 /*
423 * can_init_proc - create main CAN proc directory and procfs entries
424 */
can_init_proc(struct net * net)425 void can_init_proc(struct net *net)
426 {
427 /* create /proc/net/can directory */
428 net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
429
430 if (!net->can.proc_dir) {
431 printk(KERN_INFO "can: failed to create /proc/net/can . "
432 "CONFIG_PROC_FS missing?\n");
433 return;
434 }
435
436 /* own procfs entries from the AF_CAN core */
437 net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644,
438 net->can.proc_dir, can_stats_proc_show, NULL);
439 net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS,
440 0644, net->can.proc_dir, can_reset_stats_proc_show,
441 NULL);
442 net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR,
443 0644, net->can.proc_dir, can_rcvlist_proc_show,
444 (void *)RX_ERR);
445 net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL,
446 0644, net->can.proc_dir, can_rcvlist_proc_show,
447 (void *)RX_ALL);
448 net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL,
449 0644, net->can.proc_dir, can_rcvlist_proc_show,
450 (void *)RX_FIL);
451 net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV,
452 0644, net->can.proc_dir, can_rcvlist_proc_show,
453 (void *)RX_INV);
454 net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF,
455 0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL);
456 net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF,
457 0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL);
458 }
459
460 /*
461 * can_remove_proc - remove procfs entries and main CAN proc directory
462 */
can_remove_proc(struct net * net)463 void can_remove_proc(struct net *net)
464 {
465 if (!net->can.proc_dir)
466 return;
467
468 if (net->can.pde_stats)
469 remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
470
471 if (net->can.pde_reset_stats)
472 remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
473
474 if (net->can.pde_rcvlist_err)
475 remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
476
477 if (net->can.pde_rcvlist_all)
478 remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
479
480 if (net->can.pde_rcvlist_fil)
481 remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
482
483 if (net->can.pde_rcvlist_inv)
484 remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
485
486 if (net->can.pde_rcvlist_eff)
487 remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
488
489 if (net->can.pde_rcvlist_sff)
490 remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
491
492 remove_proc_entry("can", net->proc_net);
493 }
494
