net/can/proc.c

   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
  67 static int user_reset;
  68
  69 static 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
  80 static 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
 100 static 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
 120 void 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
 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, r->matches, r->ident);
 200         }
 201 }
 202
 203 static 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
 213 static 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
 275 static 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
 296 static 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
 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
 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                 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
 342 static 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
 367 static 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
 398 static 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  */
 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_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  */
 472 void 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 }