net/can/proc.c

   1 /*
   2  * proc.c - procfs support for Protocol family CAN core module
   3  *
   4  * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of Volkswagen nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * Alternatively, provided that this notice is retained in full, this
  20  * software may be distributed under the terms of the GNU General
  21  * Public License ("GPL") version 2, in which case the provisions of the
  22  * GPL apply INSTEAD OF those given above.
  23  *
  24  * The provided data structures and external interfaces from this code
  25  * are not restricted to be used by modules with a GPL compatible license.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  28  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  29  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  30  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  31  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  32  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  33  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  34  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  35  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  36  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  37  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  38  * DAMAGE.
  39  *
  40  */
  41
  42 #include <linux/module.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/list.h>
  45 #include <linux/rcupdate.h>
  46 #include <linux/if_arp.h>
  47 #include <linux/can/core.h>
  48
  49 #include "af_can.h"
  50
  51 /*
  52  * proc filenames for the PF_CAN core
  53  */
  54
  55 #define CAN_PROC_VERSION     "version"
  56 #define CAN_PROC_STATS       "stats"
  57 #define CAN_PROC_RESET_STATS "reset_stats"
  58 #define CAN_PROC_RCVLIST_ALL "rcvlist_all"
  59 #define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
  60 #define CAN_PROC_RCVLIST_INV "rcvlist_inv"
  61 #define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
  62 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
  63 #define CAN_PROC_RCVLIST_ERR "rcvlist_err"
  64
  65 static int user_reset;
  66
  67 static const char rx_list_name[][8] = {
  68         [RX_ERR] = "rx_err",
  69         [RX_ALL] = "rx_all",
  70         [RX_FIL] = "rx_fil",
  71         [RX_INV] = "rx_inv",
  72 };
  73
  74 /*
  75  * af_can statistics stuff
  76  */
  77
  78 static void can_init_stats(struct net *net)
  79 {
  80         struct s_stats *can_stats = net->can.can_stats;
  81         struct s_pstats *can_pstats = net->can.can_pstats;
  82         /*
  83          * This memset function is called from a timer context (when
  84          * can_stattimer is active which is the default) OR in a process
  85          * context (reading the proc_fs when can_stattimer is disabled).
  86          */
  87         memset(can_stats, 0, sizeof(struct s_stats));
  88         can_stats->jiffies_init = jiffies;
  89
  90         can_pstats->stats_reset++;
  91
  92         if (user_reset) {
  93                 user_reset = 0;
  94                 can_pstats->user_reset++;
  95         }
  96 }
  97
  98 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
  99                                unsigned long count)
 100 {
 101         unsigned long rate;
 102
 103         if (oldjif == newjif)
 104                 return 0;
 105
 106         /* see can_stat_update() - this should NEVER happen! */
 107         if (count > (ULONG_MAX / HZ)) {
 108                 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
 109                        count);
 110                 return 99999999;
 111         }
 112
 113         rate = (count * HZ) / (newjif - oldjif);
 114
 115         return rate;
 116 }
 117
 118 void can_stat_update(struct timer_list *t)
 119 {
 120         struct net *net = from_timer(net, t, can.can_stattimer);
 121         struct s_stats *can_stats = net->can.can_stats;
 122         unsigned long j = jiffies; /* snapshot */
 123
 124         /* restart counting in timer context on user request */
 125         if (user_reset)
 126                 can_init_stats(net);
 127
 128         /* restart counting on jiffies overflow */
 129         if (j < can_stats->jiffies_init)
 130                 can_init_stats(net);
 131
 132         /* prevent overflow in calc_rate() */
 133         if (can_stats->rx_frames > (ULONG_MAX / HZ))
 134                 can_init_stats(net);
 135
 136         /* prevent overflow in calc_rate() */
 137         if (can_stats->tx_frames > (ULONG_MAX / HZ))
 138                 can_init_stats(net);
 139
 140         /* matches overflow - very improbable */
 141         if (can_stats->matches > (ULONG_MAX / 100))
 142                 can_init_stats(net);
 143
 144         /* calc total values */
 145         if (can_stats->rx_frames)
 146                 can_stats->total_rx_match_ratio = (can_stats->matches * 100) /
 147                         can_stats->rx_frames;
 148
 149         can_stats->total_tx_rate = calc_rate(can_stats->jiffies_init, j,
 150                                             can_stats->tx_frames);
 151         can_stats->total_rx_rate = calc_rate(can_stats->jiffies_init, j,
 152                                             can_stats->rx_frames);
 153
 154         /* calc current values */
 155         if (can_stats->rx_frames_delta)
 156                 can_stats->current_rx_match_ratio =
 157                         (can_stats->matches_delta * 100) /
 158                         can_stats->rx_frames_delta;
 159
 160         can_stats->current_tx_rate = calc_rate(0, HZ, can_stats->tx_frames_delta);
 161         can_stats->current_rx_rate = calc_rate(0, HZ, can_stats->rx_frames_delta);
 162
 163         /* check / update maximum values */
 164         if (can_stats->max_tx_rate < can_stats->current_tx_rate)
 165                 can_stats->max_tx_rate = can_stats->current_tx_rate;
 166
 167         if (can_stats->max_rx_rate < can_stats->current_rx_rate)
 168                 can_stats->max_rx_rate = can_stats->current_rx_rate;
 169
 170         if (can_stats->max_rx_match_ratio < can_stats->current_rx_match_ratio)
 171                 can_stats->max_rx_match_ratio = can_stats->current_rx_match_ratio;
 172
 173         /* clear values for 'current rate' calculation */
 174         can_stats->tx_frames_delta = 0;
 175         can_stats->rx_frames_delta = 0;
 176         can_stats->matches_delta   = 0;
 177
 178         /* restart timer (one second) */
 179         mod_timer(&net->can.can_stattimer, round_jiffies(jiffies + HZ));
 180 }
 181
 182 /*
 183  * proc read functions
 184  */
 185
 186 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
 187                               struct net_device *dev)
 188 {
 189         struct receiver *r;
 190
 191         hlist_for_each_entry_rcu(r, rx_list, list) {
 192                 char *fmt = (r->can_id & CAN_EFF_FLAG)?
 193                         "   %-5s  %08x  %08x  %pK  %pK  %8ld  %s\n" :
 194                         "   %-5s     %03x    %08x  %pK  %pK  %8ld  %s\n";
 195
 196                 seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
 197                                 r->func, r->data, r->matches, r->ident);
 198         }
 199 }
 200
 201 static void can_print_recv_banner(struct seq_file *m)
 202 {
 203         /*
 204          *                  can1.  00000000  00000000  00000000
 205          *                 .......          0  tp20
 206          */
 207         seq_puts(m, "  device   can_id   can_mask  function"
 208                         "  userdata   matches  ident\n");
 209 }
 210
 211 static int can_stats_proc_show(struct seq_file *m, void *v)
 212 {
 213         struct net *net = m->private;
 214         struct s_stats *can_stats = net->can.can_stats;
 215         struct s_pstats *can_pstats = net->can.can_pstats;
 216
 217         seq_putc(m, '\n');
 218         seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats->tx_frames);
 219         seq_printf(m, " %8ld received frames (RXF)\n", can_stats->rx_frames);
 220         seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats->matches);
 221
 222         seq_putc(m, '\n');
 223
 224         if (net->can.can_stattimer.function == can_stat_update) {
 225                 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
 226                                 can_stats->total_rx_match_ratio);
 227
 228                 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
 229                                 can_stats->total_tx_rate);
 230                 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
 231                                 can_stats->total_rx_rate);
 232
 233                 seq_putc(m, '\n');
 234
 235                 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
 236                                 can_stats->current_rx_match_ratio);
 237
 238                 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
 239                                 can_stats->current_tx_rate);
 240                 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
 241                                 can_stats->current_rx_rate);
 242
 243                 seq_putc(m, '\n');
 244
 245                 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
 246                                 can_stats->max_rx_match_ratio);
 247
 248                 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
 249                                 can_stats->max_tx_rate);
 250                 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
 251                                 can_stats->max_rx_rate);
 252
 253                 seq_putc(m, '\n');
 254         }
 255
 256         seq_printf(m, " %8ld current receive list entries (CRCV)\n",
 257                         can_pstats->rcv_entries);
 258         seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
 259                         can_pstats->rcv_entries_max);
 260
 261         if (can_pstats->stats_reset)
 262                 seq_printf(m, "\n %8ld statistic resets (STR)\n",
 263                                 can_pstats->stats_reset);
 264
 265         if (can_pstats->user_reset)
 266                 seq_printf(m, " %8ld user statistic resets (USTR)\n",
 267                                 can_pstats->user_reset);
 268
 269         seq_putc(m, '\n');
 270         return 0;
 271 }
 272
 273 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
 274 {
 275         struct net *net = m->private;
 276         struct s_pstats *can_pstats = net->can.can_pstats;
 277         struct s_stats *can_stats = net->can.can_stats;
 278
 279         user_reset = 1;
 280
 281         if (net->can.can_stattimer.function == can_stat_update) {
 282                 seq_printf(m, "Scheduled statistic reset #%ld.\n",
 283                                 can_pstats->stats_reset + 1);
 284         } else {
 285                 if (can_stats->jiffies_init != jiffies)
 286                         can_init_stats(net);
 287
 288                 seq_printf(m, "Performed statistic reset #%ld.\n",
 289                                 can_pstats->stats_reset);
 290         }
 291         return 0;
 292 }
 293
 294 static int can_version_proc_show(struct seq_file *m, void *v)
 295 {
 296         seq_printf(m, "%s\n", CAN_VERSION_STRING);
 297         return 0;
 298 }
 299
 300 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 301                                              struct net_device *dev,
 302                                              struct can_dev_rcv_lists *d)
 303 {
 304         if (!hlist_empty(&d->rx[idx])) {
 305                 can_print_recv_banner(m);
 306                 can_print_rcvlist(m, &d->rx[idx], dev);
 307         } else
 308                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 309
 310 }
 311
 312 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 313 {
 314         /* double cast to prevent GCC warning */
 315         int idx = (int)(long)PDE_DATA(m->file->f_inode);
 316         struct net_device *dev;
 317         struct can_dev_rcv_lists *d;
 318         struct net *net = m->private;
 319
 320         seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
 321
 322         rcu_read_lock();
 323
 324         /* receive list for 'all' CAN devices (dev == NULL) */
 325         d = net->can.can_rx_alldev_list;
 326         can_rcvlist_proc_show_one(m, idx, NULL, d);
 327
 328         /* receive list for registered CAN devices */
 329         for_each_netdev_rcu(net, dev) {
 330                 if (dev->type == ARPHRD_CAN && dev->ml_priv)
 331                         can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 332         }
 333
 334         rcu_read_unlock();
 335
 336         seq_putc(m, '\n');
 337         return 0;
 338 }
 339
 340 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
 341                                                struct net_device *dev,
 342                                                struct hlist_head *rcv_array,
 343                                                unsigned int rcv_array_sz)
 344 {
 345         unsigned int i;
 346         int all_empty = 1;
 347
 348         /* check whether at least one list is non-empty */
 349         for (i = 0; i < rcv_array_sz; i++)
 350                 if (!hlist_empty(&rcv_array[i])) {
 351                         all_empty = 0;
 352                         break;
 353                 }
 354
 355         if (!all_empty) {
 356                 can_print_recv_banner(m);
 357                 for (i = 0; i < rcv_array_sz; i++) {
 358                         if (!hlist_empty(&rcv_array[i]))
 359                                 can_print_rcvlist(m, &rcv_array[i], dev);
 360                 }
 361         } else
 362                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 363 }
 364
 365 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 366 {
 367         struct net_device *dev;
 368         struct can_dev_rcv_lists *d;
 369         struct net *net = m->private;
 370
 371         /* RX_SFF */
 372         seq_puts(m, "\nreceive list 'rx_sff':\n");
 373
 374         rcu_read_lock();
 375
 376         /* sff receive list for 'all' CAN devices (dev == NULL) */
 377         d = net->can.can_rx_alldev_list;
 378         can_rcvlist_proc_show_array(m, NULL, d->rx_sff, ARRAY_SIZE(d->rx_sff));
 379
 380         /* sff receive list for registered CAN devices */
 381         for_each_netdev_rcu(net, dev) {
 382                 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 383                         d = dev->ml_priv;
 384                         can_rcvlist_proc_show_array(m, dev, d->rx_sff,
 385                                                     ARRAY_SIZE(d->rx_sff));
 386                 }
 387         }
 388
 389         rcu_read_unlock();
 390
 391         seq_putc(m, '\n');
 392         return 0;
 393 }
 394
 395 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
 396 {
 397         struct net_device *dev;
 398         struct can_dev_rcv_lists *d;
 399         struct net *net = m->private;
 400
 401         /* RX_EFF */
 402         seq_puts(m, "\nreceive list 'rx_eff':\n");
 403
 404         rcu_read_lock();
 405
 406         /* eff receive list for 'all' CAN devices (dev == NULL) */
 407         d = net->can.can_rx_alldev_list;
 408         can_rcvlist_proc_show_array(m, NULL, d->rx_eff, ARRAY_SIZE(d->rx_eff));
 409
 410         /* eff receive list for registered CAN devices */
 411         for_each_netdev_rcu(net, dev) {
 412                 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 413                         d = dev->ml_priv;
 414                         can_rcvlist_proc_show_array(m, dev, d->rx_eff,
 415                                                     ARRAY_SIZE(d->rx_eff));
 416                 }
 417         }
 418
 419         rcu_read_unlock();
 420
 421         seq_putc(m, '\n');
 422         return 0;
 423 }
 424
 425 /*
 426  * can_init_proc - create main CAN proc directory and procfs entries
 427  */
 428 void can_init_proc(struct net *net)
 429 {
 430         /* create /proc/net/can directory */
 431         net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
 432
 433         if (!net->can.proc_dir) {
 434                 printk(KERN_INFO "can: failed to create /proc/net/can . "
 435                            "CONFIG_PROC_FS missing?\n");
 436                 return;
 437         }
 438
 439         /* own procfs entries from the AF_CAN core */
 440         net->can.pde_version = proc_create_net_single(CAN_PROC_VERSION, 0644,
 441                         net->can.proc_dir, can_version_proc_show, NULL);
 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.pde_version)
 471                 remove_proc_entry(CAN_PROC_VERSION, net->can.proc_dir);
 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         if (net->can.proc_dir)
 498                 remove_proc_entry("can", net->proc_net);
 499 }