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         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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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  */
 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  */
 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 }