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/net/can/proc.c

http://github.com/mirrors/linux
C | 503 lines | 320 code | 95 blank | 88 comment | 49 complexity | 9ba369bcb1b4c907d8042467b7c0e774 MD5 | raw file
  1// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) 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_VERSION     "version"
 58#define CAN_PROC_STATS       "stats"
 59#define CAN_PROC_RESET_STATS "reset_stats"
 60#define CAN_PROC_RCVLIST_ALL "rcvlist_all"
 61#define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
 62#define CAN_PROC_RCVLIST_INV "rcvlist_inv"
 63#define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
 64#define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
 65#define CAN_PROC_RCVLIST_ERR "rcvlist_err"
 66
 67static int user_reset;
 68
 69static const char rx_list_name[][8] = {
 70	[RX_ERR] = "rx_err",
 71	[RX_ALL] = "rx_all",
 72	[RX_FIL] = "rx_fil",
 73	[RX_INV] = "rx_inv",
 74};
 75
 76/*
 77 * af_can statistics stuff
 78 */
 79
 80static void can_init_stats(struct net *net)
 81{
 82	struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
 83	struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
 84	/*
 85	 * This memset function is called from a timer context (when
 86	 * can_stattimer is active which is the default) OR in a process
 87	 * context (reading the proc_fs when can_stattimer is disabled).
 88	 */
 89	memset(pkg_stats, 0, sizeof(struct can_pkg_stats));
 90	pkg_stats->jiffies_init = jiffies;
 91
 92	rcv_lists_stats->stats_reset++;
 93
 94	if (user_reset) {
 95		user_reset = 0;
 96		rcv_lists_stats->user_reset++;
 97	}
 98}
 99
100static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
101			       unsigned long count)
102{
103	unsigned long rate;
104
105	if (oldjif == newjif)
106		return 0;
107
108	/* see can_stat_update() - this should NEVER happen! */
109	if (count > (ULONG_MAX / HZ)) {
110		printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
111		       count);
112		return 99999999;
113	}
114
115	rate = (count * HZ) / (newjif - oldjif);
116
117	return rate;
118}
119
120void can_stat_update(struct timer_list *t)
121{
122	struct net *net = from_timer(net, t, can.stattimer);
123	struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
124	unsigned long j = jiffies; /* snapshot */
125
126	/* restart counting in timer context on user request */
127	if (user_reset)
128		can_init_stats(net);
129
130	/* restart counting on jiffies overflow */
131	if (j < pkg_stats->jiffies_init)
132		can_init_stats(net);
133
134	/* prevent overflow in calc_rate() */
135	if (pkg_stats->rx_frames > (ULONG_MAX / HZ))
136		can_init_stats(net);
137
138	/* prevent overflow in calc_rate() */
139	if (pkg_stats->tx_frames > (ULONG_MAX / HZ))
140		can_init_stats(net);
141
142	/* matches overflow - very improbable */
143	if (pkg_stats->matches > (ULONG_MAX / 100))
144		can_init_stats(net);
145
146	/* calc total values */
147	if (pkg_stats->rx_frames)
148		pkg_stats->total_rx_match_ratio = (pkg_stats->matches * 100) /
149			pkg_stats->rx_frames;
150
151	pkg_stats->total_tx_rate = calc_rate(pkg_stats->jiffies_init, j,
152					    pkg_stats->tx_frames);
153	pkg_stats->total_rx_rate = calc_rate(pkg_stats->jiffies_init, j,
154					    pkg_stats->rx_frames);
155
156	/* calc current values */
157	if (pkg_stats->rx_frames_delta)
158		pkg_stats->current_rx_match_ratio =
159			(pkg_stats->matches_delta * 100) /
160			pkg_stats->rx_frames_delta;
161
162	pkg_stats->current_tx_rate = calc_rate(0, HZ, pkg_stats->tx_frames_delta);
163	pkg_stats->current_rx_rate = calc_rate(0, HZ, pkg_stats->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	pkg_stats->tx_frames_delta = 0;
177	pkg_stats->rx_frames_delta = 0;
178	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
188static 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
203static void can_print_recv_banner(struct seq_file *m)
204{
205	/*
206	 *                  can1.  00000000  00000000  00000000
207	 *                 .......          0  tp20
208	 */
209	seq_puts(m, "  device   can_id   can_mask  function"
210			"  userdata   matches  ident\n");
211}
212
213static int can_stats_proc_show(struct seq_file *m, void *v)
214{
215	struct net *net = m->private;
216	struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
217	struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
218
219	seq_putc(m, '\n');
220	seq_printf(m, " %8ld transmitted frames (TXF)\n", pkg_stats->tx_frames);
221	seq_printf(m, " %8ld received frames (RXF)\n", pkg_stats->rx_frames);
222	seq_printf(m, " %8ld matched frames (RXMF)\n", pkg_stats->matches);
223
224	seq_putc(m, '\n');
225
226	if (net->can.stattimer.function == can_stat_update) {
227		seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
228				pkg_stats->total_rx_match_ratio);
229
230		seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
231				pkg_stats->total_tx_rate);
232		seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
233				pkg_stats->total_rx_rate);
234
235		seq_putc(m, '\n');
236
237		seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
238				pkg_stats->current_rx_match_ratio);
239
240		seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
241				pkg_stats->current_tx_rate);
242		seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
243				pkg_stats->current_rx_rate);
244
245		seq_putc(m, '\n');
246
247		seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
248				pkg_stats->max_rx_match_ratio);
249
250		seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
251				pkg_stats->max_tx_rate);
252		seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
253				pkg_stats->max_rx_rate);
254
255		seq_putc(m, '\n');
256	}
257
258	seq_printf(m, " %8ld current receive list entries (CRCV)\n",
259			rcv_lists_stats->rcv_entries);
260	seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
261			rcv_lists_stats->rcv_entries_max);
262
263	if (rcv_lists_stats->stats_reset)
264		seq_printf(m, "\n %8ld statistic resets (STR)\n",
265				rcv_lists_stats->stats_reset);
266
267	if (rcv_lists_stats->user_reset)
268		seq_printf(m, " %8ld user statistic resets (USTR)\n",
269				rcv_lists_stats->user_reset);
270
271	seq_putc(m, '\n');
272	return 0;
273}
274
275static int can_reset_stats_proc_show(struct seq_file *m, void *v)
276{
277	struct net *net = m->private;
278	struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats;
279	struct can_pkg_stats *pkg_stats = net->can.pkg_stats;
280
281	user_reset = 1;
282
283	if (net->can.stattimer.function == can_stat_update) {
284		seq_printf(m, "Scheduled statistic reset #%ld.\n",
285				rcv_lists_stats->stats_reset + 1);
286	} else {
287		if (pkg_stats->jiffies_init != jiffies)
288			can_init_stats(net);
289
290		seq_printf(m, "Performed statistic reset #%ld.\n",
291				rcv_lists_stats->stats_reset);
292	}
293	return 0;
294}
295
296static int can_version_proc_show(struct seq_file *m, void *v)
297{
298	seq_printf(m, "%s\n", CAN_VERSION_STRING);
299	return 0;
300}
301
302static 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
314static 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		if (dev->type == ARPHRD_CAN && dev->ml_priv)
333			can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
334	}
335
336	rcu_read_unlock();
337
338	seq_putc(m, '\n');
339	return 0;
340}
341
342static inline void can_rcvlist_proc_show_array(struct seq_file *m,
343					       struct net_device *dev,
344					       struct hlist_head *rcv_array,
345					       unsigned int rcv_array_sz)
346{
347	unsigned int i;
348	int all_empty = 1;
349
350	/* check whether at least one list is non-empty */
351	for (i = 0; i < rcv_array_sz; i++)
352		if (!hlist_empty(&rcv_array[i])) {
353			all_empty = 0;
354			break;
355		}
356
357	if (!all_empty) {
358		can_print_recv_banner(m);
359		for (i = 0; i < rcv_array_sz; i++) {
360			if (!hlist_empty(&rcv_array[i]))
361				can_print_rcvlist(m, &rcv_array[i], dev);
362		}
363	} else
364		seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
365}
366
367static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
368{
369	struct net_device *dev;
370	struct can_dev_rcv_lists *dev_rcv_lists;
371	struct net *net = m->private;
372
373	/* RX_SFF */
374	seq_puts(m, "\nreceive list 'rx_sff':\n");
375
376	rcu_read_lock();
377
378	/* sff receive list for 'all' CAN devices (dev == NULL) */
379	dev_rcv_lists = net->can.rx_alldev_list;
380	can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff,
381				    ARRAY_SIZE(dev_rcv_lists->rx_sff));
382
383	/* sff receive list for registered CAN devices */
384	for_each_netdev_rcu(net, dev) {
385		if (dev->type == ARPHRD_CAN && dev->ml_priv) {
386			dev_rcv_lists = dev->ml_priv;
387			can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff,
388						    ARRAY_SIZE(dev_rcv_lists->rx_sff));
389		}
390	}
391
392	rcu_read_unlock();
393
394	seq_putc(m, '\n');
395	return 0;
396}
397
398static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
399{
400	struct net_device *dev;
401	struct can_dev_rcv_lists *dev_rcv_lists;
402	struct net *net = m->private;
403
404	/* RX_EFF */
405	seq_puts(m, "\nreceive list 'rx_eff':\n");
406
407	rcu_read_lock();
408
409	/* eff receive list for 'all' CAN devices (dev == NULL) */
410	dev_rcv_lists = net->can.rx_alldev_list;
411	can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff,
412				    ARRAY_SIZE(dev_rcv_lists->rx_eff));
413
414	/* eff receive list for registered CAN devices */
415	for_each_netdev_rcu(net, dev) {
416		if (dev->type == ARPHRD_CAN && dev->ml_priv) {
417			dev_rcv_lists = dev->ml_priv;
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 */
432void 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_version = proc_create_net_single(CAN_PROC_VERSION, 0644,
445			net->can.proc_dir, can_version_proc_show, NULL);
446	net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644,
447			net->can.proc_dir, can_stats_proc_show, NULL);
448	net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS,
449			0644, net->can.proc_dir, can_reset_stats_proc_show,
450			NULL);
451	net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR,
452			0644, net->can.proc_dir, can_rcvlist_proc_show,
453			(void *)RX_ERR);
454	net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL,
455			0644, net->can.proc_dir, can_rcvlist_proc_show,
456			(void *)RX_ALL);
457	net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL,
458			0644, net->can.proc_dir, can_rcvlist_proc_show,
459			(void *)RX_FIL);
460	net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV,
461			0644, net->can.proc_dir, can_rcvlist_proc_show,
462			(void *)RX_INV);
463	net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF,
464			0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL);
465	net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF,
466			0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL);
467}
468
469/*
470 * can_remove_proc - remove procfs entries and main CAN proc directory
471 */
472void can_remove_proc(struct net *net)
473{
474	if (net->can.pde_version)
475		remove_proc_entry(CAN_PROC_VERSION, net->can.proc_dir);
476
477	if (net->can.pde_stats)
478		remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
479
480	if (net->can.pde_reset_stats)
481		remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
482
483	if (net->can.pde_rcvlist_err)
484		remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
485
486	if (net->can.pde_rcvlist_all)
487		remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
488
489	if (net->can.pde_rcvlist_fil)
490		remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
491
492	if (net->can.pde_rcvlist_inv)
493		remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
494
495	if (net->can.pde_rcvlist_eff)
496		remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
497
498	if (net->can.pde_rcvlist_sff)
499		remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
500
501	if (net->can.proc_dir)
502		remove_proc_entry("can", net->proc_net);
503}