net/can/proc.c

   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 }