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 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
326
327 if (can_ml)
328 can_rcvlist_proc_show_one(m, idx, dev,
329 &can_ml->dev_rcv_lists);
330 }
331
332 rcu_read_unlock();
333
334 seq_putc(m, '\n');
335 return 0;
336 }
337
can_rcvlist_proc_show_array(struct seq_file * m,struct net_device * dev,struct hlist_head * rcv_array,unsigned int rcv_array_sz)338 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
339 struct net_device *dev,
340 struct hlist_head *rcv_array,
341 unsigned int rcv_array_sz)
342 {
343 unsigned int i;
344 int all_empty = 1;
345
346 /* check whether at least one list is non-empty */
347 for (i = 0; i < rcv_array_sz; i++)
348 if (!hlist_empty(&rcv_array[i])) {
349 all_empty = 0;
350 break;
351 }
352
353 if (!all_empty) {
354 can_print_recv_banner(m);
355 for (i = 0; i < rcv_array_sz; i++) {
356 if (!hlist_empty(&rcv_array[i]))
357 can_print_rcvlist(m, &rcv_array[i], dev);
358 }
359 } else
360 seq_printf(m, " (%s: no entry)\n", DNAME(dev));
361 }
362
can_rcvlist_sff_proc_show(struct seq_file * m,void * v)363 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
364 {
365 struct net_device *dev;
366 struct can_dev_rcv_lists *dev_rcv_lists;
367 struct net *net = m->private;
368
369 /* RX_SFF */
370 seq_puts(m, "\nreceive list 'rx_sff':\n");
371
372 rcu_read_lock();
373
374 /* sff receive list for 'all' CAN devices (dev == NULL) */
375 dev_rcv_lists = net->can.rx_alldev_list;
376 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff,
377 ARRAY_SIZE(dev_rcv_lists->rx_sff));
378
379 /* sff receive list for registered CAN devices */
380 for_each_netdev_rcu(net, dev) {
381 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
382
383 if (can_ml) {
384 dev_rcv_lists = &can_ml->dev_rcv_lists;
385 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff,
386 ARRAY_SIZE(dev_rcv_lists->rx_sff));
387 }
388 }
389
390 rcu_read_unlock();
391
392 seq_putc(m, '\n');
393 return 0;
394 }
395
can_rcvlist_eff_proc_show(struct seq_file * m,void * v)396 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
397 {
398 struct net_device *dev;
399 struct can_dev_rcv_lists *dev_rcv_lists;
400 struct net *net = m->private;
401
402 /* RX_EFF */
403 seq_puts(m, "\nreceive list 'rx_eff':\n");
404
405 rcu_read_lock();
406
407 /* eff receive list for 'all' CAN devices (dev == NULL) */
408 dev_rcv_lists = net->can.rx_alldev_list;
409 can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff,
410 ARRAY_SIZE(dev_rcv_lists->rx_eff));
411
412 /* eff receive list for registered CAN devices */
413 for_each_netdev_rcu(net, dev) {
414 struct can_ml_priv *can_ml = can_get_ml_priv(dev);
415
416 if (can_ml) {
417 dev_rcv_lists = &can_ml->dev_rcv_lists;
418 can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff,
419 ARRAY_SIZE(dev_rcv_lists->rx_eff));
420 }
421 }
422
423 rcu_read_unlock();
424
425 seq_putc(m, '\n');
426 return 0;
427 }
428
429 /*
430 * can_init_proc - create main CAN proc directory and procfs entries
431 */
can_init_proc(struct net * net)432 void can_init_proc(struct net *net)
433 {
434 /* create /proc/net/can directory */
435 net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
436
437 if (!net->can.proc_dir) {
438 printk(KERN_INFO "can: failed to create /proc/net/can . "
439 "CONFIG_PROC_FS missing?\n");
440 return;
441 }
442
443 /* own procfs entries from the AF_CAN core */
444 net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644,
445 net->can.proc_dir, can_stats_proc_show, NULL);
446 net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS,
447 0644, net->can.proc_dir, can_reset_stats_proc_show,
448 NULL);
449 net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR,
450 0644, net->can.proc_dir, can_rcvlist_proc_show,
451 (void *)RX_ERR);
452 net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL,
453 0644, net->can.proc_dir, can_rcvlist_proc_show,
454 (void *)RX_ALL);
455 net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL,
456 0644, net->can.proc_dir, can_rcvlist_proc_show,
457 (void *)RX_FIL);
458 net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV,
459 0644, net->can.proc_dir, can_rcvlist_proc_show,
460 (void *)RX_INV);
461 net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF,
462 0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL);
463 net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF,
464 0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL);
465 }
466
467 /*
468 * can_remove_proc - remove procfs entries and main CAN proc directory
469 */
can_remove_proc(struct net * net)470 void can_remove_proc(struct net *net)
471 {
472 if (!net->can.proc_dir)
473 return;
474
475 if (net->can.pde_stats)
476 remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
477
478 if (net->can.pde_reset_stats)
479 remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
480
481 if (net->can.pde_rcvlist_err)
482 remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
483
484 if (net->can.pde_rcvlist_all)
485 remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
486
487 if (net->can.pde_rcvlist_fil)
488 remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
489
490 if (net->can.pde_rcvlist_inv)
491 remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
492
493 if (net->can.pde_rcvlist_eff)
494 remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
495
496 if (net->can.pde_rcvlist_sff)
497 remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
498
499 remove_proc_entry("can", net->proc_net);
500 }
501